GEOGRAPHICAL REVIEW, Issue 3 2006
Karl S. Zimmerer
ABSTRACT. Alexander von Humboldt engaged in a staggering array of diverse experiences in the Andes and adjoining lowlands of northwestern South America between 1801 and 1803. Yet examination of Humboldt's diaries, letters, and published works shows how his principal activities in the Andes centered on three interests: mining and geological landscapes; communications and cartography; and use and distribution of the quinine-yielding cinchona trees. Each node represented a pragmatic concern dealing with environmental resources in the context of the Andes. To pursue these interests in his Andean field studies, Humboldt relied on varied cultural interactions and vast social networks for knowledge exchange, in addition to extensive textual comparisons. These modes of inquiry dovetailed with his pragmatic interests and his open-ended intellectual curiosity. Fertile combinations in his Andean studies provided the foundation and main testing ground for Humboldt's fused nature-culture approach as well as his contributions to early geography and interdisciplinary environmental science. [source]

HP37 PROGNOSTIC FACTORS IN OESOPHAGEAL CANCER: NUMBER OF LYMPH NODES AND EXTRACAPSULAR LYMPH NODE INVASION , AN INTERIM ANALYSIS

ANZ JOURNAL OF SURGERY, Issue 2007
S. K. Thompson
Purpose Controversy exists over the 2nd edition of the TNM staging system introduced by the American Joint Committee in Cancer in 1988, and revised in 2002. Prognostic pathological factors such as the number of positive lymph nodes and any extracapsular lymph node invasion may refine this current staging system and optimize patient treatment. Methodology All patients who underwent surgical resection for oesophageal cancer were identified in a prospectively-maintained database. Patients without invasive adenocarcinoma or squamous cell cancer were excluded. Pathology slides were reviewed by a single pathologist. Survival data was calculated using Kaplan-Meier curves, and prognostic factors were examined using the log rank test. Results 235 surgical specimens met inclusion criteria, and 95 specimens have been reviewed so far. The 5-yr overall survival rate was 43% (median 31.4 months). Subdividing pN-stage into 1,2 positive nodes and >2 positive nodes showed significant differences in 5-yr survival between both groups: 41% vs. 6.0%, respectively (P = 0.0003). Similarly, including absence and presence of extracapsular lymph node invasion into our pathology review showed significant differences in 5-yr survival: 40% vs. 7.8%, respectively (P < 0.01). A negative circumferential margin, and the absence of both vascular and perineural invasion were also found to significantly improve survival rates. Conclusions The number and characteristics of metastatic invasion of lymph nodes should be included in current oesophageal cancer staging systems. Clinicians will then have more accurate prognostic information, and treatment can be better tailored to patients' needs. [source]

THE NUMBER OF NEGATIVE PELVIC LYMPH NODES REMOVED DOES NOT AFFECT THE RISK OF BIOCHEMICAL FAILURE AFTER RADICAL PROSTATECTOMY

BJU INTERNATIONAL, Issue 10 2010
Christopher Eden
No abstract is available for this article. [source]

Detection of Micrometastasis in the Sentinel Lymph Node via Lymphoscintigraphy for a Patient With In-Transit Metastatic Melanoma

DERMATOLOGIC SURGERY, Issue 9 2003
Chih-Hsun Yang MD
Background. Lymphoscintigraphy and sentinel lymph node (SLN) biopsy are highly accurate methods of detecting regional lymph node status for melanoma. Previously, these procedures were mainly performed in patients with primary melanoma before wide local excision. Objective. To present a case with in-transit recurrence melanoma using lymphoscintigraphy and SLN biopsy for detection of nodal basin status. Methods. The patient discussed here had a subungual melanoma that developed as an in-transit metastatic melanoma on the pretibia area 2 years after right big toe amputation. By using lymphoscintigraphy and SLN biopsy technique with injection of technetium-99m colloid around the in-transit metastatic site, the first node (SLN) draining the in-transit metastatic tumor was identified and harvested on the right inguinal area. Immediate right inguinal node dissection was subsequently performed. Results. Under thorough histologic examination, the first node (SLN) draining the in-transit metastatic tumor was the only node that contained micrometastatic tumor cells in the surgical specimens. Conclusion. Lymphoscintigraphy and SLN biopsy techniques are sensitive procedures for detecting the regional nodal basin micrometastasis in in-transit recurrence melanoma patients. [source]

Upper and lower bounds for natural frequencies: A property of the smoothed finite element methods

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 2 2010
Zhi-Qian Zhang
Abstract Node-based smoothed finite element method (NS-FEM) using triangular type of elements has been found capable to produce upper bound solutions (to the exact solutions) for force driving static solid mechanics problems due to its monotonic ,soft' behavior. This paper aims to formulate an NS-FEM for lower bounds of the natural frequencies for free vibration problems. To make the NS-FEM temporally stable, an ,-FEM is devised by combining the compatible and smoothed strain fields in a partition of unity fashion controlled by ,,[0, 1], so that both the properties of stiff FEM and the monotonically soft NS-FEM models can be properly combined for a desired purpose. For temporally stabilizing NS-FEM, , is chosen small so that it acts like a ,regularization parameter' making the NS-FEM stable, but still with sufficient softness ensuring lower bounds for natural frequency solution. Our numerical studies demonstrate that (1) using a proper ,, the spurious non-zero energy modes can be removed and the NS-FEM becomes temporally stable; (2) the stabilized NS-FEM becomes a general approach for solids to obtain lower bounds to the exact natural frequencies over the whole spectrum; (3) ,-FEM can even be tuned for obtaining nearly exact natural frequencies. Copyright © 2010 John Wiley & Sons, Ltd. [source]

Morphological Traits above the Flag Leaf Node as Indicators of Drought Susceptibility Index in Durum Wheat

JOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 2 2007
D. Villegas
Abstract Selection criteria for drought tolerance would be helpful tools for wheat breeding programmes. To assess the usefulness of some morphological traits above the flag leaf node as indicators of yield and the susceptibility index (SI) of Fischer and Maurer, 10 durum wheat genotypes were used in experiments conducted under two water regimes at two latitudes in Spain during 3 years. Morphological traits were measured at anthesis, and yield, yield components and quality traits were evaluated at ripening. Principal components analysis showed associations between morphological traits and yield, yield components and quality, most of them caused by differences between environments. Peduncle weight, spike weight and length and awn length were significantly related to SI within environments. Spike and peduncle weight were the traits more related to yield and SI in all the experiments together and in the rainfed sites, while in the irrigated sites spike length was better. The spike weight and length were negatively associated with SI, while peduncle weight was positively associated to SI. Genotype means across all experiments were associated with SI values. These morphological traits could be selection criteria in breeding programmes to obtain varieties with good yield stability. The genetic variability found suggests opportunity for selection. [source]

An Autopsy Case of Brugada Syndrome with Significant Lesions in the Sinus Node

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 3 2005
SHIN-ICHIRO MORIMOTO M.D.
A 30-year-old man with Brugada syndrome died suddenly. The heart weighed 380 g. The left ventricular wall showed mild thickening, and marked fatty tissue deposition was noted in the right ventricular outflow tract. Neither ventricle was enlarged. Contraction band necrosis was diffuse in both ventricles. In the ventricles no cardiac muscle cell hypertrophy or atrophy, or significant interstitial fibrosis was observed. In the sinus node the number of nodal cells was reduced by half, with fatty tissue and fibrosis prominent. But no lesions were evident in the right bundle branch. [source]

Sustained Inward Current and Pacemaker Activity of Mammalian Sinoatrial Node

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2002
HENGGUI ZHANG Ph.D.
Sustained Inward Current in the Sinoatrial Node.Introduction: A novel sustained inward Na+ current ist, which sensitive to Ca2+ -antagonists and potentiated by beta-adrenergic stimulation, has been described in pacemaker cells of rabbit, guinea pig, and rat sinoatrial node, as well as rabbit AV node. Although ist has been suggested to be an important pacemaker current, this has never been tested experimentally because of the lack of a specific blocker. In this study, we address the role of ist in the pacemaker activity of the sinoatrial node cell using computer models. Methods and Results: The newly developed models of Zhang et al. for peripheral and central rabbit sinoatrial node cells and models of Noble and Noble, Demir et al., Wilders et al., and Dokos et al. for typical rabbit sinoatrial node cells were modified to incorporate equations for ist. The conductance gst was chosen to give a current density-voltage relationship consistent with experimental data. In the models of Zhang et al. (periphery), Noble and Noble, and Dokos et al., in which ist was smaller or about the same amplitude as other inward currents, ist increased the pacemaking rate by 0.6%, 2.2%, and 0.8%, respectively. In the models of Zhang et al. (center), Demir et al., and Wilders et al., in which ist was larger than some other inward ionic currents, ist increased the pacemaking rate by 7%, 20%, and 14%, respectively. Conclusion: ist has the potential to be a regulator of pacemaker activity, although its importance will depend on the amplitude of ist relative to the amplitude of other inward currents involved in pacemaker activity. [source]

Independent Autonomic Modulation of Sinus Node and Ventricular Myocardium in Healthy Young Men During Sleep

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2000
PETER KOWALLIK M.D.
Autonomic Modulation of Sinus Node and Ventricle. Introduction. The aim of this study was to investigate whether autonomic modulation of ventricular repolarization may spontaneousiy differ from that of the sinoatrial node. Methods and Results. Onset of P waves. QRS complexes, and the apex and end of T waves were detected heat to heat in high-resolution ECGs from nine healthy young men during the night. There were time-dependent fluctuations in the QT/RR slopes of consecutive 5-minute segments that could not he explained by the mean RR cycle length of the respective segment. Because the variahility found in QT intervals could not be explained hy either possible effects of rate dependence or hysteresis, autonomic effects were obvious. Power speetral analysis was performed for consecutive 5-minute segments of PP and QT techograms. In a given subject. trends in the time course of low-frequency (LF) and high-frequency (HF) power in PP and QT often were similar, but they were quite different at other times. The mean LF/HF ratio for QTend (0.75 ± 0.1) was different from that of PP (1.8 ± 0.2; P = 0.002), indicating differences in sympathovagal balance at the different anatomic sites. Furthermore, at a given mean heart rate, averaged QT intervals were different on a time scale of several minutes to hours. The QT/RR slope of 5-minute segments correlated significantly with the HF power of QT variability but not with that of PP variability, indicating effects of the autonomic nervous system on ventricular action potential restitution. Conclusion. These differences demonstrate that changes in sinus node automaticity are not necessarily indicative of the autonomic control of ventricular myocardium. (J Cardiavasc Electrophysiol, Vol. II, pp. 1063-1070. October 2000) [source]

Total and Differential Leucocyte Counts and Lymphocyte Subpopulations in Lymph, Afferent and Efferent to the Supramammary Lymph Node, During Endotoxin-Induced Bovine Mastitis

REPRODUCTION IN DOMESTIC ANIMALS, Issue 2 2007
S Lun
Contents Leucocyte trafficking in afferent and efferent mammary lymph and the supramammary lymph node in cows was examined during 4 h after intramammary infusion of endotoxin from Escherichia coli. Total and differential leucocyte counts were measured in milk, blood and lymph. The proportions of CD4+, CD8+, major histocompatibility complex (MHC) class II+ and IgM+ lymphocytes were examined in the lymph and lymph node. At post-infusion hour (PIH) 4, the flow rates of both lymph fluids had increased approximately eightfold. Total leucocyte concentration increased in afferent lymph, but decreased in efferent lymph. Neutrophils increased in afferent lymph at PIH 2 and in efferent lymph and milk at PIH 4. The predominant cell type in afferent lymph shifted from lymphocyte to neutrophil while lymphocyte was still at PIH 4 the predominant type in efferent lymph. Among the lymphocytes, B cells were predominant in afferent lymph and lymph node at PIH 4 while T cells, mainly CD4+ cells, were predominant in efferent lymph both at PIH 0 and PIH 4. The CD4 : CD8 ratio was higher in efferent lymph and the challenged lymph node than in afferent lymph and the control node, respectively. There was a significant difference in proportions of each lymphocyte subpopulation except for IgM+ cells, between afferent and efferent lymph after infusion. According to the results, there was already during the first hours of the immune response, a non-random trafficking of neutrophils and lymphocyte subpopulations resulting in a changed distribution of cells in afferent and efferent lymph and a difference in lymphocyte reactivity between the two lymph fluids. [source]

Metastatic "Borderline" Papillary Ovarian Tumor in an Intramammary Lymph Node

THE BREAST JOURNAL, Issue 5 2002
André L. Moreira MD
No abstract is available for this article. [source]

The Clinical Significance of Coexpression of Cyclooxygenases-2, Vascular Endothelial Growth Factors, and Epidermal Growth Factor Receptor in Nasopharyngeal Carcinoma

THE LARYNGOSCOPE, Issue 11 2008
Jianji Pan MD
Abstract Objectives/Hypothesis: To investigate the inter-relationship of the expressions of cyclooxygenases-2 (COX-2), vascular endothelial growth factors (VEGF), and epidermal growth factor receptor (EGFR) in nasopharyngeal cancer (NPC) cells, and their clinical significance in association with the extent of disease at diagnosis. Study Design: Prospective. Methods: Expressions of COX-2, VEGF, and EGFR protein were detected using immunohistochemistry in 111 patients with pathologically confirmed stage II to IV nasopharyngeal carcinoma. The correlation between the expressions of the three tumor markers and the stages of disease at diagnosis were investigated. Results: COX-2, VEGF, and EGFR were over-expressed in 76.6, 66.7, and 73.9% of NPC cells, respectively. The staining patterns was cytoplasmic for VEGF, membranous for EGFR, and both cytoplasmic and membranous for COX-2 in tumor cells. Linear associations were observed between the intensity of the expressions of COX-2 vs. VEGF, COX-2 vs. EGFR, or VEGF vs. EGFR. Furthermore, the intensity of the expressions of all three markers was significantly associated with the extent of the tumor measured by the Tumor, Node, Metastasis classification and staging grouping of the American Joint Committee on Cancer/International Union Against Cancer staging system. Conclusion: COX-2, VEGF, and EGFR expressions in NPC cells were interrelated, and the intensity of the expressions of all three markers were significantly associated with the stage of the disease at diagnosis. Further investigation is needed to determine the clinical applications of COX-2, VEGF, and EGFR in predicting the long-term outcome of NPC after definitive therapy. [source]

Dynamics of Mast Cells in Lymph Node Following Antigenic Stimulation

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2004
D. O. Dabak
Summary Dynamics of mast cells in rat cervical lymph nodes were examined using conventional histological techniques after injection of Salmonella paratyphi B-H antigen. There was no significant change in the number of mast cells at sixth hour and on the first day of stimulation compared with the controls. The number of mast cells was increased in all lymph node compartments on the second day of stimulation, which continued in the following 3 days. On the eighth day of stimulation, although the mast cell number decreased in the subcapsular area, it was still high in the paracortical area and medullary sinuses of the lymph nodes. On the second day of stimulation, the mast cell number was apparently increased in the subcapsular area than those of the other compartments. In the following days of stimulation, the highest number of mast cells was seen in the medullary sinuses. The highest paracortical mast cell number was determined on the third day of stimulation and some mast cells were observed near the high endothelial venules (HEVs). The changes of mast cell number among the lymph node compartments after antigenic stimulation support the hypothesis that the migration of mast cells occurred. This migration pattern indicates that mast cells enter the lymph node via afferent lymphatics and migrate to the lymph node compartments following antigenic stimulation. [source]

Implication of intraoperative sentinel node imprint cytology for consent in the SNAC trial

ANZ JOURNAL OF SURGERY, Issue 3 2004
Melissa A. Bochner
Background: Women randomized into the sentinel node biopsy-only arm of the Sentinel Node versus Axillary Clearance Trial require axillary clearance if the sentinel node is unable to be identified, or if the sentinel node contains metastases. The aim of the present study was to determine the likelihood of immediate and delayed axillary clearance in patients in the trial when nodes were subjected to intraoperative imprint cytology. Methods: A prospective database for 400 patients with operable breast cancer was analysed to determine the likelihood of lymph node involvement according to tumour size. The ability to successfully remove a sentinel node and the accuracy of intraoperative imprint cytology of sentinel nodes was investigated. These data were used to predict the likelihood of patients proceeding to immediate or delayed axillary clearance. Results: The rate of lymph node involvement was 0%, 10%, 30%, and 53% in tumours measuring <5 mm, 6,10 mm, 11,20 mm and 21,30 mm, respectively. A sentinel node was identified in 95% of cases. In a series of 79 consecutive cases using intraoperative imprint cytology, 37% of sentinel nodes containing metastases were identified intraoperatively. The estimated likelihood of undergoing immediate axillary clearance therefore ranges from 5% for tumours <5 mm, up to 24% for tumours 21,30 mm. Similarly the likelihood of delayed clearance ranges from 0% to 32% depending on tumour size. Conclusions: It is possible to give detailed and accurate information to patients undergoing sentinel node biopsy about both the risk of lymph node involvement and the likelihood of requiring immediate or secondary axillary clearance. [source]

The First Homochiral Diamond-Like Coordination Polymer Containing Cubane Cluster (Cu4I4) as Connecting Node and Cinchonine as Donor-Acceptor (or Push-Pull Electronic Effect) Building Block

CHINESE JOURNAL OF CHEMISTRY, Issue 10 2007
Guo-Xi WANG
Abstract The reaction of CuI with cinchonine (an organic donor-acceptor chromophore) afforded a homochiral 3D diamondoid network [Cu4I4(cinchonine)2]n (1) containing a cubane cluster (Cu4I4) as a connecting node. This is the first homochiral coordination polymer with diamondoid nets containing a cluster as a connecting note. Its thermal stability and solid state optical properties such as fluorescence, circular dichroism and second-harmonic generation response were also reported. [source]

Nodes and Connections: Science Museums in the Network Age,

CURATOR THE MUSEUM JOURNAL, Issue 1 2002
Rob Semper
For some it is a convenient way to market their offerings, for others it has become a fundamental cornerstone of their practice. Questions still remain about the role of the Web in the museum world and the interplay between the physical and virtual worlds. Developing a strong research agenda and fostering a shared community of practice are two necessary components if museums are to maximize the potential that the Web has to offer them. [source]

Dispersion of Nodes Added to a Network

GEOGRAPHICAL ANALYSIS, Issue 4 2005
Michael Kuby
For location problems in which optimal locations can be at nodes or along arcs but no finite dominating set has been identified, researchers may desire a method for dispersing p additional discrete candidate sites along the m arcs of a network. This article develops and tests minimax and maximin models for solving this continuous network location problem, which we call the added-node dispersion problem (ANDP). Adding nodes to an arc subdivides it into subarcs. The minimax model minimizes the maximum subarc length, while the maximin model maximizes the minimum subarc length. Like most worst-case objectives, the minimax and maximin objectives are plagued by poorly behaved alternate optima. Therefore, a secondary MinSumMax objective is used to select the best-dispersed alternate optima. We prove that equal spacing of added nodes along arcs is optimal to the MinSumMax objective. Using this fact we develop greedy heuristic algorithms that are simple, optimal, and efficient (O(mp)). Empirical results show how the maximum subarc, minimum subarc, and sum of longest subarcs change as the number of added nodes increases. Further empirical results show how using the ANDP to locate additional nodes can improve the solutions of another location problem. Using the p-dispersion problem as a case study, we show how much adding ANDP sites to the network vertices improves the p-dispersion objective function compared with (a) network vertices only and (b) vertices plus randomly added nodes. The ANDP can also be used by itself to disperse facilities such as stores, refueling stations, cell phone towers, or relay facilities along the arcs of a network, assuming that such facilities already exist at all nodes of the network. [source]

Using High Hydraulic Conductivity Nodes to Simulate Seepage Lakes

GROUND WATER, Issue 2 2002
Mary P. Anderson
In a typical ground water flow model, lakes are represented by specified head nodes requiring that lake levels be known a priori. To remove this limitation, previous researchers assigned high hydraulic conductivity (K) values to nodes that represent a lake, under the assumption that the simulated head at the nodes in the high-K zone accurately reflects lake level. The solution should also produce a constant water level across the lake. We developed a model of a simple hypothetical ground water/lake system to test whether solutions using high-K lake nodes are sensitive to the value of K selected to represent the lake. Results show that the larger the contrast between the K of the aquifer and the K of the lake nodes, the smaller the error tolerance required for the solution to converge. For our test problem, a contrast of three orders of magnitude produced a head difference across the lake of 0.005 m under a regional gradient of the order of 10,3 m/m, while a contrast of four orders of magnitude produced a head difference of 0.001 m. The high-K method was then used to simulate lake levels in Pretty Lake, Wisconsin. Results for both the hypothetical system and the application to Pretty Lake compared favorably with results using a lake package developed for MODFLOW (Merritt and Konikow 2000). While our results demonstrate that the high-K method accurately simulates lake levels, this method has more cumbersome postprocessing and longer run times than the same problem simulated using the lake package. [source]

Sentinel node in head and neck cancer: Use of size criterion to upstage the no neck in head and neck squamous cell carcinoma,

HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 2 2007
Lee W. T. Alkureishi MBChB
Abstract Background. Anatomical imaging tools demonstrate poor sensitivity in head and neck squamous cell carcinoma (HNSCC) patients with clinically node-negative necks (cN0). This study evaluates nodal size as a staging criterion for detection of cervical metastases, utilizing sentinel node biopsy (SNB) and additional pathology (step-serial sectioning, SSS; and immunohistochemistry, IHC). Methods. Sixty-five patients with clinically N0 disease underwent SNB, with a mean of 2.4 nodes excised per patient. Nodes were fixed in formalin, bisected, and measured in 3 axes before hematoxylin-eosin staining. Negative nodes were subjected to SSS and IHC. SNB-positive patients underwent modified radical neck dissection. Results. Maximum diameter was larger in levels II and III (13.1 and 13.2 mm) when compared with level I (10.5 mm; p = .004, p = .018), while minimum diameter was constant. Positive nodes were larger than negative nodes (p = .007), but nodes found positive by SSS/IHC were not significantly larger than negative nodes for either measurement (p = .433). Sensitivity and specificity were poor for all measurements. Conclusions. Nodal size is an inaccurate predictor of nodal metastases and should not be regarded as an accurate means of staging the clinically N0 neck. © 2006 Wiley Periodicals, Inc. Head Neck, 2006 [source]

A particle finite element method applied to long wave run-up

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 3 2006
J. Birknes
Abstract This paper presents a Lagrangian,Eulerian finite element formulation for solving fluid dynamics problems with moving boundaries and employs the method to long wave run-up. The method is based on a set of Lagrangian particles which serve as moving nodes for the finite element mesh. Nodes at the moving shoreline are identified by the alpha shape concept which utilizes the distance from neighbouring nodes in different directions. An efficient triangulation technique is then used for the mesh generation at each time step. In order to validate the numerical method the code has been compared with analytical solutions and a preexisting finite difference model. The main focus of our investigation is to assess the numerical method through simulations of three-dimensional dam break and long wave run-up on curved beaches. Particularly the method is put to test for cases where different shoreline segments connect and produce a computational domain surrounding dry regions. Copyright © 2006 John Wiley & Sons, Ltd. [source]

New method of dynamic color doppler signal quantification in metastatic lymph nodes compared to direct polarographic measurements of tissue oxygenation

INTERNATIONAL JOURNAL OF CANCER, Issue 6 2005
Thomas Scholbach
Abstract Tumor growth depends on sufficient blood and oxygen supply. Hypoxia stimulates neovascularization and is a known cause for radio- and chemoresistance. The objective of this study was to investigate the use of a novel ultrasound technique for the dynamic assessment of vascularization and oxygenation in metastatic lymph nodes. Twenty-four patients (age 44,78 years) with cervical lymph node metastases of squamous cell head and neck cancer were investigated by color duplex sonography and 17 (age 46,78 years) were investigated additionally with polarography. Sonography was performed after contrast enhancer infusion under defined conditions. Intranodal perfusion data (color hue, colored area) were measured automatically by a novel software technique. This allows an evaluation of blood flow dynamics by calculating perfusion intensity,velocity, perfused area, as well as the novel parameters tissue resistance index (TRI) and tissue pulsatility index (TPI),for each point of a complete heart cycle. Tumor tissue pO2 was measured by means of polarographic needle electrodes placed intranodally. The sonographic and polarographic data were correlated using Pearson's test. Sonography demonstrated a statistically significant inverse correlation between hypoxia and perfusion and significant TPI and TRI changes with different N-stages. The percentage of nodal fraction with less than 10 mmHg oxygen saturation was significantly inversely correlated with lymph node perfusion (r = ,0.551; p = 0.021). Nodes with a perfusion of less than 0.05 cm/sec flow velocity showed significantly larger hypoxic areas (p = 0.006). Significant differences of TPI and TRI existed between nodes in stage N1 and N2/N3 (p = 0.028 and 0.048, respectively). This new method of dynamic signal quantification allows a noninvasive and quantitative assessment of tumor and metastatic lymph node perfusion by means of commonly available ultrasound equipment. © 2004 Wiley-Liss, Inc. [source]

Panbiogeographical analysis of the genus Bomarea (Alstroemeriaceae)

JOURNAL OF BIOGEOGRAPHY, Issue 7 2008
Fernando Alzate
Abstract Aim, A panbiogeographical analysis of the genus Bomarea was undertaken in order to determine generalized tracks and biogeographical nodes, and to evaluate the current distribution of the genus based on the available tectonic information and the biogeographical regionalization of Latin America. Location, The Neotropical region from northern Mexico to northern Argentina, and the Nearctic and Andean regions. Method, A total of 2205 records of 101 species were analysed, representing 95% of the species assigned to Bomarea. Localities were represented on maps and their individual tracks were drawn. Based on their comparison, generalized tracks were detected and mapped. Nodes were identified in the areas where different generalized tracks were superimposed. Results, Five generalized tracks were recovered. One is located in the Eastern Central America and Western Panamanian Isthmus provinces (Caribbean subregion, Neotropical region), which was supported by three species of Central American distribution. The four remaining generalized tracks were located in South America, in the North Andean Paramo, Cauca and Puna biogeographical provinces. These tracks were supported by species of Bomarea with an Andean distribution. Biogeographical nodes were established in the Central Andean region of Colombia, central Ecuador and central Peru. Main conclusions, The nodes obtained for Bomarea support a hybrid origin for the Andean region, which presents diverse components from both northern and southern South America. Likewise, the track recovered between Colombia and Ecuador includes Andean and Neotropical areas, providing further support for this hypothesis. The nodes obtained are coherent with vicariant elements evident for Bomarea. Species of three clades proposed for Bomarea are distributed in specific generalized tracks. [source]

Computation and presentation of graphs displaying closure hierarchies of Jordan and Kronecker structures

NUMERICAL LINEAR ALGEBRA WITH APPLICATIONS, Issue 6-7 2001
Erik Elmroth
Abstract StratiGraph, a Java-based tool for computation and presentation of closure hierarchies of Jordan and Kronecker structures is presented. The tool is based on recent theoretical results on stratifications of orbits and bundles of matrices and matrix pencils. A stratification reveals the complete hierarchy of nearby structures, information critical for explaining the qualitative behaviour of linear systems under perturbations. StratiGraph facilitates the application of these theories and visualizes the resulting hierarchy as a graph. Nodes in the graph represent orbits or bundles of matrices or matrix pencils. Edges represent covering relations in the closure hierarchy. Given a Jordan or Kronecker structure, a user can obtain the complete information of nearby structures simply by mouse clicks on nodes of interest. This contribution gives an overview of the StratiGraph tool, presents its main functionalities and other features, and illustrates its use by sample applications. Copyright © 2001 John Wiley & Sons, Ltd. [source]

Nodes of large degree in random trees and forests

RANDOM STRUCTURES AND ALGORITHMS, Issue 3 2006
Bernhard Gittenberger
We study the asymptotic behavior of the number Nk,n of nodes of given degree k in unlabeled random trees, when the tree size n and the node degree k both tend to infinity. It is shown that Nk,n is asymptotically normal if and asymptotically Poisson distributed if . If , then the distribution degenerates. The same holds for rooted, unlabeled trees and forests. © 2006 Wiley Periodicals, Inc. Random Struct. Alg., 2006 [source]

Benign Inclusion of Axillary Lymph Nodes: Report of Two Cases and Literature Review

THE BREAST JOURNAL, Issue 6 2009
Charles Chuang MD
No abstract is available for this article. [source]

Assessing the Significance of Occult Micrometastases in Axillary Lymph Nodes from Breast Cancer Patients

THE BREAST JOURNAL, Issue 4 2006
Donald L. Weaver MD
No abstract is available for this article. [source]

Occult Metastases in Axillary Lymph Nodes as a Predictor of Survival in Node-Negative Breast Carcinoma with Long-term Follow-up

THE BREAST JOURNAL, Issue 3 2004
Wenche Reed MD
Abstract: Increased detection rate in the lymph nodes is seen with serial sectioning or immunohistochemistry (IHC), but the importance of occult metastases is not resolved. IHC is still not recommended in routine examination of lymph nodes. Axillary lymph nodes from 385 node-negative breast cancer patients with a median follow-up of 25 years were examined with IHC for cytokeratins, applied on routine sections. The association between classic histopathologic prognostic factors and the presence of occult metastases was evaluated. Metastases were found in 45 of 385 cases (12%), 21 metastases (47%) measured ,0.2 mm, 8 (18%) were larger than 2 mm; 14 metastases were located in the subcapsular sinus, 22 in the parenchyma of the lymph node; and 51% (23/45) of the metastases were recognized on hematoxylin-eosin staining on "second look." The detection of metastases was significantly associated with the number of sectioned lymph nodes (6% metastases for one to five lymph nodes examined versus 17% for more than five lymph nodes) and with histologic subtype (metastases in 11% of the ductal versus 33% of the lobular carcinomas). No significant association was found between occult metastases and age, tumor size, histologic grade, estrogen or progesterone receptor status, p53, or c- erbB-2. Metastases larger than 2 mm predicted a poorer recurrence-free survival rate for the whole series. A subcapsular location of the metastases was a strong predictor of overall survival. Whether or not the metastases could be identified on hematoxylin-eosin sections did not have any prognostic significance. In the multivariate analysis, histologic grade, tumor size of the primary tumor, progesterone receptor status, and the presence of occult metastasis in the lymph nodes had a prognostic impact on survival with a 25-year follow-up. [source]

Surgery and Adjuvant Radiotherapy in Patients with Cutaneous Head and Neck Squamous Cell Carcinoma Metastatic to Lymph Nodes: Combined Treatment Should be Considered Best Practice,

THE LARYNGOSCOPE, Issue 5 2005
FRANZCR, Michael J. Veness MMed
Abstract Objective: Patients with cutaneous squamous cell carcinoma (SCC) may develop metastatic SCC to nodes in the head and neck. Recent data support best outcome with the addition of adjuvant radiotherapy. This study aims to present further supportive evidence. Study Design: Retrospective chart review. Methods: Patients were identified with metastatic cutaneous SCC to nodes of the head and neck treated with surgery or surgery and adjuvant radiotherapy. Relapse and outcome were analyzed using Cox regression analysis. Disease-free survival and overall survival rates were calculated using Kaplan-Meier survival curves. Results: Between 1980 to 2000, 167 patients were treated with curative intent at Westmead Hospital, Sydney. Median age was 67 years (range, 34,95) in 143 men and 24 women with a minimum follow-up of 24 months. Patients underwent surgery (21/167; 13%), or surgery and adjuvant radiotherapy (146/167; 87%). The majority (98/167; 59%) of metastatic nodes were located in the parotid and/or cervical nodes. The remaining 69 (41%) had metastatic cervical nodes (levels I,V). Forty-seven patients (28%) had recurrences, with the majority (35/47; 74%) as locoregional failures. On multivariate analysis, spread to multiple nodes and single-modality treatment significantly predicted worse survival. Patients undergoing combined treatment had a lower rate of locoregional recurrence (20% vs. 43%) and a significantly better 5-year disease-free survival rate (73% vs. 54%; P = .004) compared to surgery alone. Conclusions: In patients with metastatic cutaneous head and neck SCC, surgery and adjuvant radiotherapy provide the best chance of achieving locoregional control and should be considered best practice. [source]

Morphology of Haemal Nodes in the Roe Deer (Capreolus capreolus)

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2010
Y. Akaydin Bozkurt
With 5 figures Summary The present study was aimed at the determination of the morphology of haemal nodes in the roe deer (Capreolus capreolus). The morphology of haemal nodes located in the abdominal and thoracic cavities of six roe deer (two adult male, two adult female and two foetuses) was studied by gross inspection and histological methods. Oval- and round-shaped haemal nodes with colours varying from pink to dark red were observed particularly between the abdominal aorta and caudal vena cava, and at the beginning of the main branches of the abdominal aorta. These nodes, having connection only with blood vessels, were covered with a thin or thick capsule of connective tissue in the foetus and the adult respectively. Trabeculae were not observed in foetal nodes. In adults, the capsule, trabeculae and, in particular, the sinuses were strongly supported by reticular fibres and cells. The morphology of these nodes displayed similarity to that of other ruminant species. [source]

Metal,Organic Hendecahedra Assembled from Dinuclear Paddlewheel Nodes and Mixtures of Ditopic Linkers with 120 and 90° Bend Angles,

ANGEWANDTE CHEMIE, Issue 45 2009
Jian-Rong Li Dr.
Von ganz alleine entstehen Metall-organische hendekaedrische Käfige mit dem im Titel genannten Verfahren (siehe Bild). Dieser Ansatz könnte einen neuen Zugang zu komplexen Koordinationspolyedern eröffnen, die über herkömmliche Syntheserouten nicht zugänglich sind. [source]