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61.
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Prophylactic inferior vena cava interruption may be appropriate in trauma patients at risk for pulmonary embolism for whom anticoagulation is contraindicated. The Recovery filter is approved for removal up to 180 days from insertion. High retrieval rates need to be achieved before we can lower the threshold for inserting these filters prophylactically. The objective of this study was to evaluate the retrieval rate of the Recovery filter in this patient population and how it has influenced our practice. This is a retrospective study in which the records of 122 consecutive trauma patients in whom the Recovery filters were inserted between October 2003 and October 2005 were reviewed. Patients who had the new generation of this filter were excluded. All these filters were inserted with the intention of retrieval. We attempted to contact all these patients at 3 months. The technical factors associated with failure to retrieve these filters were reviewed. There were no complications related to filter insertion. Excluding six patients (4.9%) who expired from causes unrelated to the insertion procedure, 20 patients could not be reached (17.3%) and 21 patients declined retrieval (18.1%). The filters were considered permanent in 18 patients (15.5%) if they were not ambulatory or if they developed inferior vena cava occlusion. Inferior vena cava occlusion was diagnosed in four patients (5.5%). Seventy-three (62.9%) patients presented for follow-up and were evaluated by color venous duplex ultrasound. We attempted to retrieve the filters in 52 patients and were successful in 45 (86.5%). However, the total retrieval rate was 40.5%. All failures of retrieval were related to tilting of the filters or bending of the limbs. There were no complications related to the retrieval procedure. Insertion and retrieval of the Recovery inferior vena cava filter are safe. In spite of the thorough follow-up and the good success rate in retrieving the filters, the overall retrieval rate in this patient population is still low. This should be strongly considered at the time of insertion. Multiple factors were found to contribute. Attention to details in patient selection and follow-up as well as modifications in technique may improve the retrieval rate.  相似文献   
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The CYP11A1 gene encodes the cholesterol side chain cleavage enzyme that catalyzes the initial and rate-limiting step of steroidogenesis. A large number of epidemiologic studies have implicated the duration and degree of endogenous estrogen exposure in the development of breast cancer in women. Here, we conduct a systematic investigation of the role of genetic variation of the CYP11A1 gene in breast cancer risk in a study of 1193 breast cancer cases and 1310 matched controls from the Shanghai Breast Cancer Study. We characterize the genetic architecture of the CYP11A1 gene in a Chinese study population. We then genotype tagging polymorphisms to capture common variation at the locus for tests of association. Variants designating a haplotype encompassing the gene promoter are significantly associated with both increased expression (P = 1.6e-6) and increased breast cancer risk: heterozygote age-adjusted odds ratio (OR), 1.51 [95% confidence interval (95% CI), 1.19-1.91]; homozygote age-adjusted OR, 2.94 (95% CI, 1.22-7.12), test for trend, P = 5.0e-5. Among genes controlling endogenous estrogen metabolism, CYP11A1 harbors common variants that may influence expression to significantly modify risk of breast cancer.  相似文献   
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ABT-737 is a novel and potent Bcl-2 antagonist with single-agent activity against small-cell lung cancer (SCLC) cell lines. Here, we evaluated the contribution of Bcl-2 family members to the in vitro cellular response of several SCLC cell lines to ABT-737. Relatively higher levels of Bcl-2, Bcl-X(L), Bim and Noxa, and lower levels of Mcl-1 characterized na?ve SCLC cell lines that were sensitive to ABT-737. Conversely, a progressive decrease in the relative levels of Bcl-2 and Noxa and a progressive increase in Mcl-1 levels characterized the increased resistance of H146 cells following chronic exposure to ABT-737. Knockdown of Mcl-1 with small interfering RNA sensitized two resistant SCLC cell lines H196 and DMS114 to ABT-737 by enhancing the induction of apoptosis. Likewise, up-regulation of Noxa sensitized H196 cells to ABT-737. Combination treatment with DNA-damaging agents was extremely synergistic with ABT-737 and was associated with the down-regulation of Mcl-1 and the up-regulation of Noxa, Puma, and Bim in H196 cells. Thus, SCLC cells sensitive to ABT-737 expressed the target proteins Bcl-2 and Bcl-X(L), whereas Mcl-1 and factors regulating Mcl-1 function seem to contribute to the overall resistance of SCLC cells to ABT-737. Overall, these observations provide further insight as to the mechanistic bases for ABT-737 efficacy in SCLC and will be helpful for profiling patients and aiding in the rational design of combination therapies.  相似文献   
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It has long been appreciated that stromal cells within the breast tumor microenvironment contribute to mammary carcinogenesis. However, to date, very little is known regarding the role of local adipose‐derived stromal cells (ASCs) in the development of breast cancer. Based on pathological, epidemiological and experimental data, we postulate that breast‐derived ASCs are unique mesenchymal stem‐like cells that play a critical role in the development of breast cancer and discuss the global implications of this working model in terms of breast cancer prevention, early detection, and new targeted therapies. Mol. Carcinog. © 2010 Wiley‐Liss, Inc.  相似文献   
68.
An investigation was conducted to evaluate the effect that surface coating of the hollow-fiber membrane oxygenator had on circulating platelet count drop during cardiopulmonary bypass (CPB). Sixty patients undergoing non-emergency myocardial revascularization for coronary artery disease were randomly divided into two groups. Group one (n = 32) received the Carmeda-coated Maxima-Plus PRF oxygenator while the patients in Group two (n=28) received the Trillium-coated Affinity oxygenator during CPB. The net platelet count drops for the pump specimen (15-20 min after the initiation of bypass) for the Carmeda and the Trillium groups were 3.6 +/- 15.8% and 6.2 +/- 10.2%, respectively. The net platelet count drop for the warming specimen for the Carmeda and the Trillium groups were 2.9 +/- 19.4% and 0.5 +/- 11.0%, respectively. There were no statistically significant differences between the groups. The authors conclude that using either the Carmeda-coated Maxima-Plus PRF oxygenator or the Trillium-coated Affinity oxygenator afford similar benefits in regards to preserving circulating platelet counts during bypass.  相似文献   
69.
Utilizing a multi‐method design, the present study examined the association between maternal sleep, assessed via actigraphy and self‐reports, and permissive parenting (e.g. lax, inconsistent discipline) during adolescence, as well as the extent to which this association differed by mothers’ race/ethnicity and socioeconomic status. The sample was comprised of 234 mothers (M age = 41.76 years, SD = 6.25; 67% European‐American, 31% African‐American, 2% other race/ethnicities) and 237 adolescents (113 boys, 124 girls; M age = 15.80 years, SD = 0.80; 66% European‐American, 34% African‐American). Mothers’ sleep duration (actual sleep minutes) and quality (sleep efficiency, latency, long wake episodes) were assessed using actigraphy. Mothers also reported on their sleep problems and adolescents reported on mothers’ permissive parenting behaviours. Results revealed that actigraphy‐based longer sleep duration and shorter sleep latency were associated with lower levels of permissive parenting. Further, mothers’ race/ethnicity and socioeconomic status moderated the association between actigraphy‐based sleep quality (i.e. sleep efficiency, long wake episodes) and permissive parenting. Specifically, a negative association between sleep efficiency and permissive parenting was evident only for African‐American mothers. In addition, a positive association between more frequent night wakings and permissive parenting was evident only for mothers from lower socioeconomic status households. The findings highlight the benefits of longer and higher‐quality sleep for reducing the risk of permissive parenting, especially among ethnic minority mothers and mothers from lower socioeconomic status households.  相似文献   
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