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Zahra Eskandariyan Marjan Esfahani Zadeh Kamaleddin Haj Mohammad Ebrahim Tehrani Vida Mashayekhi Farzad Kobarfard 《Archives of pharmacal research》2014,37(3):332-339
A series of 2-(arylmethylthio)-3-phenylquinazolin-4-one derivatives have been synthesized and their antiplatelet aggregation activities were assessed against ADP and arachidonic acid-induced platelet aggregation in human plasma. Among the tested thioethers, derivative 2, 3, 5 and 16 were the most potent compounds with satisfactory IC50 for inhibition of platelet aggregation induced by ADP. Analysis of global physicochemical parameters shows some correlations between activities and molecular volume and also surface area of the studied derivatives. 相似文献
23.
Cortical Porosity Identifies Women With Osteopenia at Increased Risk for Forearm Fractures
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Yohann Bala Roger Zebaze Ali Ghasem‐Zadeh Elizabeth J Atkinson Sandra Iuliano James M Peterson Shreyasee Amin Åshild Bjørnerem L Joseph Melton III Helena Johansson John A Kanis Sundeep Khosla Ego Seeman 《Journal of bone and mineral research》2014,29(6):1356-1362
Most fragility fractures arise among the many women with osteopenia, not the smaller number with osteoporosis at high risk for fracture. Thus, most women at risk for fracture assessed only by measuring areal bone mineral density (aBMD) will remain untreated. We measured cortical porosity and trabecular bone volume/total volume (BV/TV) of the ultradistal radius (UDR) using high‐resolution peripheral quantitative computed tomography, aBMD using densitometry, and 10‐year fracture probability using the country‐specific fracture risk assessment tool (FRAX) in 68 postmenopausal women with forearm fractures and 70 age‐matched community controls in Olmsted County, MN, USA. Women with forearm fractures had 0.4 standard deviations (SD) higher cortical porosity and 0.6 SD lower trabecular BV/TV. Compact‐appearing cortical porosity predicted fracture independent of aBMD; odds ratio (OR) = 1.92 (95% confidence interval [CI] 1.10–3.33). In women with osteoporosis at the UDR, cortical porosity did not distinguish those with fractures from those without because high porosity was present in 92% and 86% of each group, respectively. By contrast, in women with osteopenia at the UDR, high porosity of the compact‐appearing cortex conferred an OR for fracture of 4.00 (95% CI 1.15–13.90). In women with osteoporosis, porosity is captured by aBMD, so measuring UDR cortical porosity does not improve diagnostic sensitivity. However, in women with osteopenia, cortical porosity was associated with forearm fractures. © 2014 American Society for Bone and Mineral Research. 相似文献
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Nader Motallebi Zadeh Seyedeh Hamideh Mortazavi Siavash Khaki Kazem Heidari Ashraf Karbasi Sedigheh Ostad Rahimi 《Archives of orthopaedic and trauma surgery》2014,134(9):1219-1225
Introduction
Using lengthening over an intramedullary nail as a technique for cosmetic purposes improves the individuals’ quality of life and provides more satisfactory results due to less external fixator period.Methods
This study reports a case series of 143 individuals who underwent bilateral tibial lengthening over an intramedullary nail for cosmetic purposes together with the review of parameters related to the surgery and complications. Level of satisfaction was measured with the standard visual analog scale at least 1 year after removal of external fixator.Results
In this study, mean (SD) age of patients was 26.6 (7.26) years. 85 (59.4 %) participants were male and 58 (40.6 %) were female. Mean end lengthening of all individuals was 6.65 cm. The mean external fixator period was 93.7 days. Complication rate was 0.74 per segment but it decreased to 0.45 when pin-tract infection was excluded. Complications were categorized based on Paley et al.’s classification as 129 problems, 85 obstacles and no sequelae. Interestingly, 44 (30.8 %) individuals had no problem and obstacle.Conclusions
Lengthening over an intramedullary nail provides bone formation in equal quality to that obtained by the conventional Ilizarov method, along with lower rate of complications. The large number of individuals involved in our study is a remarkable benefit which could be used as an appropriate sample to compare results for outcomes and complications. 相似文献25.
Somayeh Maleki Balajoo Davud Asemani Ali Khadem Hamid Soltanian‐Zadeh 《Human brain mapping》2020,41(15):4264-4287
To estimate dynamic functional connectivity (dFC), the conventional method of sliding window correlation (SWC) suffers from poor performance of dynamic connection detection. This stems from the equal weighting of observations, suboptimal time scale, nonsparse output, and the fact that it is bivariate. To overcome these limitations, we exploited the kernel‐reweighted logistic regression (KELLER) algorithm, a method that is common in genetic studies, to estimate dFC in resting state functional magnetic resonance imaging (rs‐fMRI) data. KELLER can estimate dFC through estimating both spatial and temporal patterns of functional connectivity between brain regions. This paper compares the performance of the proposed KELLER method with current methods (SWC and tapered‐SWC (T‐SWC) with different window lengths) based on both simulated and real rs‐fMRI data. Estimated dFC networks were assessed for detecting dynamically connected brain region pairs with hypothesis testing. Simulation results revealed that KELLER can detect dynamic connections with a statistical power of 87.35% compared with 70.17% and 58.54% associated with T‐SWC (p‐value = .001) and SWC (p‐value <.001), respectively. Results of these different methods applied on real rs‐fMRI data were investigated for two aspects: calculating the similarity between identified mean dynamic pattern and identifying dynamic pattern in default mode network (DMN). In 68% of subjects, the results of T‐SWC with window length of 100 s, among different window lengths, demonstrated the highest similarity to those of KELLER. With regards to DMN, KELLER estimated previously reported dynamic connection pairs between dorsal and ventral DMN while SWC‐based method was unable to detect these dynamic connections. 相似文献
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Nurit Assia Batzir Jennifer E. Posey Xiaofei Song Zeynep Coban Akdemir Jill A. Rosenfeld Chester W. Brown Emily Chen Shannon G. Holtrop Elizabeth Mizerik Margarita Nieto Moreno Katelyn Payne Annick Raas‐Rothschild Richard Scott Hilary J. Vernon Neda Zadeh Baylor‐Hopkins Center for Mendelian Genomics James R. Lupski V. Reid Sutton 《American journal of medical genetics. Part A》2020,182(1):38-52
White‐Sutton syndrome (WHSUS) is a recently‐identified genetic disorder resulting from de novo heterozygous pathogenic variants in POGZ. Thus far, over 50 individuals have been reported worldwide, however phenotypic characterization and data regarding the natural history are still incomplete. Here we report the clinical features of 22 individuals with 21 unique loss of function POGZ variants. We observed a broad spectrum of intellectual disability and/or developmental delay with or without autism, and speech delay in all individuals. Other common problems included ocular abnormalities, hearing loss and gait abnormalities. A validated sleep disordered breathing questionnaire identified symptoms of obstructive sleep apnea in 4/12 (33%) individuals. A higher‐than‐expected proportion of cases also had gastrointestinal phenotypes, both functional and anatomical, as well as genitourinary anomalies. In line with previous publications, we observed an increased body mass index (BMI) z‐score compared to the general population (mean 0.59, median 0.9; p 0.0253). Common facial features included microcephaly, broad forehead, midface hypoplasia, triangular mouth, broad nasal root and flat nasal bridge. Analysis of the Baylor Genetics clinical laboratory database revealed that POGZ variants were implicated in approximately 0.14% of cases who underwent clinical exome sequencing for neurological indications with or without involvement of other body systems. This study describes a greater allelic series and expands the phenotypic spectrum of this new syndromic form of intellectual disability and autism. 相似文献
28.
Gelareh Farshid Malcolm Pradhan John Goldblum Sharon W Weiss 《The American journal of surgical pathology》2002,26(1):14-24
Leiomyosarcomas of the somatic soft tissues (SST) are rare compared with their retroperitoneal and cutaneous counterparts and, therefore, have not been extensively studied. We have analyzed the clinicopathologic features of 42 SST leiomyosarcomas referred in consultation to determine what factors affect outcome. Cutaneous, visceral, retroperitoneal, uterine, gastrointestinal, and major vessel leiomyosarcomas were excluded. By definition all lesions possessed at least focal cytologic atypia and mitotic activity, although the latter varied from <1/10 high power fields to 66/10 high power fields. The patients (21 females and 21 males) ranged in age from 26 to 86 years (mean 60 years); tumors developed in the lower (n = 28) or upper extremity (n = 11) and trunk (n = 3). Most arose in deep (n = 27) as opposed to superficial (n = 15) soft tissue; 39 arose from a small vein. During the follow-up period (mean 47 months, range 9-162 months), 3 of 38 (8%) patients developed local recurrence and 17 of 38 metastasized (45%) mostly to the lungs. In a univariate analysis age >62 years, size >4 cm, extensive necrosis, modified updated French Federation of Cancer Centers (FFCC) grade, and whether the tumor had been "disrupted" by a previous incisional biopsy or incomplete excision were significantly correlated with metastasis. AJCC stage also approached significance (p = 0.096) but could not be reliably tested because of the sparseness of the data. In multivariate analyses the logistic regression model that best predicted metastasis at 36 months incorporated the effects of age, FFCC grade, and disruption and had a sensitivity of 94.1% and a specificity of 95.2%. Disruption was the only significant risk factor for metastasis in a multivariate analysis (relative risk 2.70; p = 0.0001) but was strongly correlated with large size and deep location. Other parameters did not improve the predictive power of the model significantly. We concluded that the majority of SST leiomyosarcomas are actually of vascular origin, an observation that has clinical and possibly biologic ramifications. Our histologic definition of leiomyosarcoma to include atypia and any level of mitotic activity appears warranted by the biologic outcome in our cases. The risk of metastasis can be calculated from a model incorporating age, FFCC grade, and disruption. Because disruption correlates with size and depth, it could represent a surrogate as opposed to causal marker for metastasis. Nevertheless, in view of their vascular origin, the possibility that tumor disruption may facilitate or promote access to the bloodstream merits further study. 相似文献
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