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Whole Series (whole + series)
Selected AbstractsDensity-Functional Calculation of the 183W and 17O NMR Chemical Shifts for Large PolyoxotungstatesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 6 2006Jose Gracia Abstract A phosphane sulfate relativistic DFT method (ZORA)has been used to calculate the 183W and 17O NMR chemicalshifts for large polyoxotungstates, including W6O192,,CH3OTiW5O183,, W5O18WIINO3,, W10O324,, ,-,-,-XW12O40n,, ,-PW9O28Br63,, P2W18O626,, PW2O143,, and W7O246,, based on their optimized molecular structures. Despite sizeable deviations between the calculated and experimental values, the calculations correctly reproduce the trends in the change of the chemical shift for both nuclei. As expected, the diamagnetic term is almost constant throughout the whole series. The change in the chemical shifts is shown to be determined by the paramagnetic term, which depends on the electronic structure of the whole anion under study and, in particular, on the local geometry around a given tungsten atom. On the other hand, there is no correlation between the chemical shift and HOMO,LUMO gap, showing that deeper occupied levels and several unoccupied orbitals play an important role in the paramagnetic term. However, analysis of the components of the paramagnetic shielding has shown that the most significant transitions determining the change of both 183W and 17O NMR chemical shifts for anions consisting of tungsten and oxygen atoms are the occupied,occupied and not the occupied,virtual ones.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Iodinated Indole Alkaloids From Plakortis simplex , New Plakohypaphorines and an Evaluation of Their Antihistamine ActivityEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 15 2004Francesca Borrelli Abstract Three new iodinated tryptophan derivatives, plakohypaphorines D,F (4,6), have been isolated from the Caribbean sponge Plakortis simplex. Their structures have been determined by applying spectroscopic methods and microwave-assisted selective dehalogenation. Compound 5 is the first naturally occurring triiodinated indole, while compound 6 is a unique metabolite because it possesses both chlorine and iodine atoms on the indole nucleus. We have evaluated the antihistamine activity of the whole series of plakohypaphorines A,F, but only the diiodinated analogues proved to be active: they display a specific antagonism of the noncompetitive type. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] THE POPULATION GENETICS OF ADAPTATION: THE ADAPTATION OF DNA SEQUENCESEVOLUTION, Issue 7 2002H. Allen Orr Abstract I describe several patterns characterizing the genetics of adaptation at the DNA level. Following Gillespie (1983, 1984, 1991), I consider a population presently fixed for the ith best allele at a locus and study the sequential substitution of favorable mutations that results in fixation of the fittest DNA sequence locally available. Given a wild type sequence that is less than optimal, I derive the fitness rank of the next allele typically fixed by natural selection as well as the mean and variance of the jump in fitness that results when natural selection drives a substitution. Looking over the whole series of substitutions required to reach the best allele, I show that the mean fitness jumps occurring throughout an adaptive walk are constrained to a twofold window of values, assuming only that adaptation begins from a reasonably fit allele. I also show that the first substitution and the substitution of largest effect account for a large share of the total fitness increase during adaptation. I further show that the distribution of selection coefficients fixed throughout such an adaptive walk is exponential (ignoring mutations of small effect), a finding reminiscent of that seen in Fisher's geometric model of adaptation. Last, I show that adaptation by natural selection behaves in several respects as the average of two idealized forms of adaptation, perfect and random. [source] A case-control study on hormone therapy as a risk factor for breast cancer in Finland: Intrauterine system carries a risk as wellINTERNATIONAL JOURNAL OF CANCER, Issue 2 2010Heli K. Lyytinen Abstract The purpose of this study was to evaluate the association between postmenopausal hormone therapy (HT) and the risk for breast cancer in recently postmenopausal Finnish women. All Finnish women with first invasive breast cancer diagnosed between the ages of 50 and 62 years during 1995,2007 (n = 9,956) were identified from the Finnish Cancer Registry. For each case, 3 controls of the same age were retrieved from the Finnish Population Register. The cases and controls were linked to the national medical reimbursement register to assess the use of HT. The odds ratios (ORs) and 95% confidence intervals (CIs) for breast cancer were calculated with conditional logistic regression analysis, adjusting for parity, age at the first birth and health care district. Estradiol-only therapy (991 users with breast cancer, n) or oral progestagen (n = 138) was not accompanied by an increased risk. Estradiol-progestagen therapy (EPT) (n = 1,731) was associated with an elevated risk in the whole series (OR 1.36; 95% CI 1.27,1.46). The risk became detectable in less than 3 years of use. Continuous EPT use tended to be associated with a higher risk for breast cancer than the sequential EPT use. The use of tibolone (n = 80) (1.36; 1.15,1.96), a levonorgestrel-releasing intrauterine system (LNG,IUS) alone (n = 154) (1.45; 1.97,1.77) or as a complement to estradiol (n = 137) (2.15; 1.72,2.68) was also associated with an increased risk. The association between HT use and the risk for breast cancer shows a large variation between various forms of HT, and also the use of LNG-IUS may carry a risk. [source] Left Ventricular Reconstruction for Ischemic CardiomyopathyJOURNAL OF CARDIAC SURGERY, Issue 3 2002Vincent Dor M.D. The technique is conducted under a totally arrested heart; coronary revascularization is accomplished first. The mitral valve is checked by TEE and repaired if necessary. Endocardectomy and cryotherapy are used in case of ventricular tachycardia. At the limit between scarred and normal tissue, a continuous suture is tied on a balloon inflated at the theoretical diastolic volume of the patient, and a patch is fixed inside the ventricle. Autologous tissue can be also used. The experience of the author is more than 1000 cases since 1984. The global hospital mortality of the whole series is 7.3%, and 13% in patients with very poor ejection fraction (<30%). In the series of the last 3 years, these mortality rates are 4.8% and 7.9%, respectively. Both geometry and performances of the LV are improved, and the mean increase of ejection fraction is between 10 and 15 points. Three causes can explain delayed impairment; continuum in remodeling, lack in diastolic capacity, or absence of mitral repair. After an infarct, with or without successful coronary recanalization, that leaves a large asynergic scarred ventricle (50% of LV circumference), LVR is recommended to avoid or prevent permanent congestive heart failure with global dilatation. In end-stage ischemic cardiomyopathy with congestive heart failure, and poor response to full medical therapy, LVR, with acceptable risk, could slow down the remodeling and avoid or delay heart transplantation. [source] NMR-based analysis of structure of heteroleptic triple-decker (phthalocyaninato) (porphyrinato) lanthanides in solutionsMAGNETIC RESONANCE IN CHEMISTRY, Issue 7 2010Kirill P. Birin Abstract A novel approach for the structural analysis of heteroleptic triple-decker (porphyrinato)(phthalocyaninato) lanthanides(III) in solutions is developed. The developed approach consists in molecular mechanics (MM+) optimization of the geometry of the complex taking into account the lanthanide-induced shift (LIS) datasets. LISs of the resonance peaks in 1H NMR spectra of a series of symmetric complexes [An4P]Ln[(15C5)4Pc]Ln[An4P], where An4P2, is 5,10,15,20-tetrakis(4-methoxyphenyl)porphyrinato-dianion, [(15C5)4Pc]2, is 2,3,9,10,16,17,24,25-tetrakis(15-crown-5)phthalocyaninato-dianion and Ln = La, Ce, Pr, Nd, Sm, Eu, are analyzed. Analysis of LISs showed two sets of protons in the molecule with opposite signs of shift. Two-nuclei analysis of LISs testifies isostructurality of the whole series of investigated complexes in solution despite contraction of the lanthanide ions. Model-free separation of contact and dipolar contributions of LISs was performed with one-nucleus technique and did not show changes in contact and dipolar terms within the investigated series. MM+ optimization of the molecular structure allowed the interpretation of features of LIS for each particular group of protons. Parameterization of MM + -optimized model of molecule with values of structure-dependent dipolar contributions of LIS allows the development of the precise structural model of the triple-decker complex in solution. This approach allows the determination of the geometry and structure of the sandwich macrocyclic tetrapyrrolic complexes together with conformational analysis of flexible peripheral substituents in solutions. The developed method can be applied with minor modifications for the determination of structural parameters of other types of lanthanides(III) complexes with tetrapyrrolic ligands and also supramolecular systems based on them. Copyright © 2010 John Wiley & Sons, Ltd. [source] Clinical etiological classification of scoliosis: report of 1289 casesORTHOPAEDIC SURGERY, Issue 1 2009Yong Qiu MD Objective:, With the development of diagnostic techniques and in-depth understanding of lateral curvature of the spine (scoliosis), it is possible to differentiate idiopathic scoliosis from other forms with various known etiologies. The present study was to analyze data collected at the authors' center according to the current etiological spectrum and classification of scoliosis. Methods:, One thousand, two hundred and eighty-nine consecutive patients with different forms of structural scoliosis were reviewed. The average age at first visit was 18 years, ranging from 4 months to 79 years. Corrective surgery was performed on patients aged from 9 to 28 years; their clinical data were retrieved for independent statistical analyses, and further compared with those obtained from the whole group. Results:, The prevalence of non-idiopathic scoliosis was 25.3% in the whole series, but it increased to 34% in the surgical group aged from 9 to 28 years. Thirty-nine percent of patients with congenital scoliosis presented at least one developmental spinal cord malformation. Conclusion:, The current study has shown that the etiological distribution of scoliosis has changed a lot from what was true decades ago. Developmental malformation related to scoliosis is one of the risk factors for neurological complications during corrective surgery, so it is important to make an accurate diagnosis and take appropriate prophylactic measures to avoid relative neurological complications. [source] Contextualism and the Factivity ProblemPHILOSOPHY AND PHENOMENOLOGICAL RESEARCH, Issue 3 2008PETER BAUMANN Epistemological contextualism - the claim that the truth-value of knowledge-attributions can vary with the context of the attributor - has recently faced a whole series of objections. The most serious one, however, has not been discussed much so far: the factivity objection. In this paper, I explain what the objection is and present three different versions of the objection. I then show that there is a good way out for the contextualist. However, in order to solve the problem the contextualist has to accept a relationalist version of contextualism. [source] Occult Metastases in Axillary Lymph Nodes as a Predictor of Survival in Node-Negative Breast Carcinoma with Long-term Follow-upTHE BREAST JOURNAL, Issue 3 2004Wenche 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] Three isomorphous 2,6-dibromopyridinium tetrabromidometallates: (C5H4Br2N)2[MBr4]·2H2O (M = Cu, Cd and Hg)ACTA CRYSTALLOGRAPHICA SECTION C, Issue 11 2009Rawhi H. Al-Far The structures of three isomorphous compounds, namely bis(2,6-dibromopyridinium) tetrabromidocuprate(II) dihydrate, (C5H4Br2N)2[CuBr4]·2H2O, bis(2,6-dibromopyridinium) tetrabromidocadmate(II) dihydrate, (C5H4Br2N)2[CdBr4]·2H2O, and bis(2,6-dibromopyridinium) tetrabromidomercurate(II) dihydrate, (C5H4Br2N)2[HgBr4]·2H2O, show a crystal supramolecularity represented by M,Br...H,O,H...Br,M intermolecular interactions along with (,)N,H...OH2 hydrogen-bonding interactions forming layers connected via aryl,aryl face-to-face stacking of cations, leading to a three-dimensional network. The anions have significantly distorted tetrahedral geometry and crystallographic C2 symmetry. The stability of this crystal lattice is evidenced by the crystallization of a whole series of isomorphous compounds. [source] Pancreatic fistula after distal pancreatectomy: incidence, risk factors and managementANZ JOURNAL OF SURGERY, Issue 9 2010Chiow Adrian Kah Heng Abstract Background:, Pancreatic fistulae post distal pancreatectomy still leads to significant morbidity and if not properly managed, may lead to mortality. The identification of risk factors and effective management of patients with pancreatic fistulae is important in the prevention of these complications. Methods:, There were 75 open consecutive distal pancreatectomies in the Department of Surgery, Changi General Hospital from May 2001 to May 2007. Results:, The indications for operation were neuroendocrine tumours (n= 15), adenocarcinoma (n= 20), Intraductal papillary mucinous tumour (IPMT) (n= 20), serous cysts (n= 15) and trauma (n= 5). There were 20 patients (27%) who developed pancreatic fistulae in the whole series. On univariate analysis, the patients with pancreatic fistulae had significantly more pre-morbidities, softer pancreas and use of staplers as a method of closure of the pancreatic remnant. On multivariate analysis, the use of staplers and soft pancreas were significant independent risk factors for the development of pancreatic fistulae in our patient population. All of the patients with pancreatic fistulae were successfully treated non-surgically with no mortality in the whole series. Conclusions:, The use of stapler on soft pancreas leads to a higher risk for pancreatic fistulae after distal pancreatectomies. Most pancreatic fistulae can be managed non-surgically with good outcome. [source] Long-term results of a combination of paclitaxel, cisplatin and gemcitabine for salvage therapy in male germ-cell tumoursBJU INTERNATIONAL, Issue 3 2009Nicola Nicolai OBJECTIVE To retrospectively review the long-term activity, efficacy and toxicity of the combination of paclitaxel, cisplatin and gemcitabine (TPG) as third- or further-line chemotherapy in patients with germ-cell tumours (GCTs) who are not cured after at least two courses of standard-dose chemotherapy, high-dose chemotherapy or both. PATIENTS AND METHODS We evaluated 22 consecutive men treated between April 1999 and December 2000. Half of them were classified as absolutely refractory to cisplatin and a further two as refractory. The median (range) number of previous courses of chemotherapy was 8 (5,11). Treatment consisted of paclitaxel 80 mg/m2, cisplatin 50 mg/m2 and gemcitabine 800 mg/m2 on days 1 and 8, every 3 weeks for four courses, followed by surgery of actual residual resectable masses. RESULTS The follow-up was updated at August 2007. There were no deaths from toxicity and only one patient needed suspension of therapy for toxicity. There was both grade 3,4 thrombocytopenia and neutropenia in 15 patients (68%), and anaemia in nine (41%). There were partial remissions in eight (36%) patients. Six (27%) patients were rendered disease-free with surgical removal of a residual mass after chemotherapy (two still containing viable cancer). Four (18%) patients are long-term survivors at more than 80, 81, 94 and 99 months. The median (range) overall survival of the whole series was 13.5 (1,>99) months. CONCLUSION This combination had a toxicity profile that was acceptable and comparable with other third-line regimens. There were eight (36%) major responses. After a 6-year minimum follow-up, four (18%) patients were long-term disease-free survivors. [source] The dirhodium-method in the determination of absolute configurations of phospholene chalcogenidesCHIRALITY, Issue 6 2006Stefan Moeller Abstract The 1H, 13C, and 31P NMR signals of six chiral phospholene chalcogenides (X = O, S, Se) are duplicated in the presence of one mole equivalent of the chiral auxiliary Rh2[(R)-MTPA]4 (diastereomeric dispersion ,,; in Hz). The samples were investigated as nonracemic mixtures of enantiomers with known absolute configurations so that signs can be attributed to the ,,-values and each signal set can be assigned to the respective enantiomer. The signs are uniform , in particular those of 1H nuclei , and nearly independent of the nature of the chalcogen atom. Thus, if the absolute configuration of one compound is known, it is possible to derive absolute configurations in the whole series (correlation method). Chirality, 2006. © 2006 Wiley-Liss, Inc. [source] Scleral wrap increases the long-term complication risk of bone-derived hydroxyapatite orbital implantsCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 8 2008Tze'Yo Toh MBBS(Hons) Abstract Background:, This study was prompted by previous findings that suggested that scleral wrapping increased the rate of complications following insertion of bone-derived hydroxyapatite orbital implants and compared the long-term results of implants inserted with and without scleral wraps. Methods:, This retrospective case series reviewed the long-term outcomes of 159 patients who had undergone enucleation with insertion of a bone-derived hydroxyapatite orbital implant at Dunedin Hospital between 1977 and 2006. Implants were inserted with and without scleral wraps in 85 and 74 cases, respectively. Follow up was 0.5,27.5 years (mean 8.2 years) for the whole series and 9.7 years for the sclera group and 6.7 years for the group without sclera. Patient details were obtained from theatre records, case note review, patient interview and examination, interview of patient relatives and family general practitioner records. The main outcome measures were the rates of minor or major complications and their treatments and outcomes. Results:, Twenty-seven cases (17%) suffered minor complications of limited implant exposure that either healed spontaneously, with implant drilling or wound resuturing and 11 cases (7%) suffered major complications requiring explantation. Of 38 patients with postoperative complications, 31 (82%) had scleral wraps compared with 7 (18%) without sclera (P < 0.001; OR 5.14, 95% CI 2.00,14.78). Conclusion:, Bone-derived hydroxyapatite orbital implants inserted without scleral wrap were associated with better clinical outcomes and a lower rate of long-term complications. It is therefore recommended that these implants be inserted without a scleral wrap. [source] The relationships between learning outcomes and methods of teaching anatomy as perceived by professional anatomistsCLINICAL ANATOMY, Issue 2 2008K.M. Patel Abstract Changes in the teaching of gross anatomy have often involved decreasing student contact time alongside the use of new methods for teaching. However, there remains controversy over teaching methods and about whether cadaveric dissection by students should remain the preferred method. Furthermore, decisions concerning changes to curricula are more likely to be taken by choosing a method of teaching rather than by proper evaluation of what are the desired learning outcomes for a course in anatomy. The purpose of this study was to ascertain the attitudes of anatomists in Europe towards the methods of teaching best fitting a series of learning outcomes for anatomy and secondarily to test the hypothesis that, from evaluation of learning outcomes, anatomy is best taught by cadaveric dissection by the students. About 113 completed questionnaires were received from anatomists who are employed at higher education institutions that use various teaching methods. Most anatomists (69%) favored the use of cadaveric dissection above other teaching methods when considering the whole series of learning comes, this method seeming to achieve a range of different course aims/objectives, P < 0.001; Kruskal,Wallis). Consequently, these findings are consistent with our initial hypothesis. However, when individual learning outcomes were considered, the relationship was not so clear cut and, for example, little difference was discernible between teaching methods when considering learning outcomes related to the acquisition of anatomical knowledge. The use of human cadaveric dissection gained more approval when the skills-base was considered rather than just the content(knowledge)-base of an anatomical course. Clin. Anat. 21:182,189, 2008. © 2008 Wiley-Liss, Inc. [source] Posterior pelvic exenteration for primary rectal cancerCOLORECTAL DISEASE, Issue 4 2006G. C. Bannura Abstract Background, Indications for and the prognosis of posterior pelvic exenteration (PPE) in rectal cancer patients are not clearly defined. The aim of this study was to analyse the indications, complications and long-term results of PPE in patients with primary rectal cancer. Methods, A retrospective review included patient demographics, tumour and treatment variables, and morbidity, recurrence, and survival statistics. These results were compared with a group of female patients who underwent standard resection for primary rectal cancer in the same period (non PPE group). Results, The series included 30 women with an average age of 56.7 years (range 22,78). Tumour location was recorded in three cases in the upper rectum, 13 cases in the medium rectum and 14 cases in the lower rectum. A sphincter-preserving procedure was performed in 70% of the patients. Mean operative time was 4.2 h (range 2,7.5 h). Overall major morbidity rate in this series was 50% and mean hospital stay was 19.7 days (range 9,60 days). There was no hospital mortality. Pathological reports showed direct invasion of uterus, vagina or rectovaginal septum in 19 cases, involvement of perirectal tissue in 25 cases and positive lymph nodes in 18 cases. Comparison between PPE and non PPE groups showed no differences in mean tumour diameter, histological grade and tumour stage, but patients in the first group were younger. Although low tumours were seen more frequently in the PPE group (P = 0.003), the rate of sphincter-preserving procedure was comparable in both groups. Operative time was longer (P = 0.04) and morbidity was higher (P = 0.0058) in the PPE group. Local recurrence with or without distant metastases for the whole series was 30%. Five-year survival rate for patients who underwent curative resections (TNM I,III) was 48% in the PPE group vs 62% in the non PPE group (P = 0.09). Conclusions, In the present series, PPE prolonged operative time, increased postoperative complications and showed a trend toward poor prognosis in recurrence and survival. However, PPE offers the only hope for cure to patients with a primary rectal cancer that is adherent or invades reproductive organs. [source] Utility of appropriate peritonitis grading in the surgical management of perforated sigmoid diverticulitisCOLORECTAL DISEASE, Issue 6 2000K. Thaler Objective We evaluated the prognostic validity of preoperative risk scores in the surgical management of patients with diverticular perforation and diffuse peritonitis. Patients and methods From 1988 to 1998, 82 patients, mean age 72 ± 15 years, underwent urgent surgery for perforated diverticulitis with generalized peritonitis. They were operated either with the Hartmann technique or with resection and primary anastomosis. ASA Classification and Mannheimer Peritonitis Index (MPI) were documented as risk scores at time of surgery and used as guidelines to decide for one of both procedures. Results A Hartmann resection (HA) was performed in 62 patients (76%) and resection with primary anastomosis (PA) in 20 (24%). Seventy-one percent of patients in the HA group corresponded to ASA IV/V, compared with 35% in the group with primary anastomosis (P < 0.001). Patients with Hartmann resection had also a higher MPI (23 ± 8) vs those with primary anastomosis (18 ± 7; P < 0.004). However, differences between the HA group and the PA group due to post-operative morbidity (21% vs 35%) and mortality (35% vs 20%) did not reach statistical significance. Nevertheless, multivariate analysis of the whole series revealed a significant relationship between MPI and mortality (P < 0.0043), independent of ASA class, age and operative procedure. Conclusion Patients assigned to Hartmann procedure had more co-morbidities and more advanced peritonitis as assessed by increased ASA and higher MPI. The Mannheimer Peritonitis Index proved to be an independent prognostic index in estimating mortality with respect to peritonitis extension and septic status of the patient. [source] | ||||||||||||||||