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排序方式: 共有804条查询结果,搜索用时 13 毫秒
51.
We investigated the effect of dl-α-lipoic acid (LA) supplementation and regular aerobic exercise on the concentrations of malondialdehyde (MDA) and vitamin E, the activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx), and the levels of glutathione (GSH) in rat skeletal muscles (soleus and red gastrocnemius). For 8 weeks, rats (n = 7 per group) were (1) exercised on a treadmill for 30 min d−1, (2) treated with supplemental LA, or (3) exercised and treated with supplemental LA. Control rats (n = 7) did not receive LA and were not exercised. dl-α-Lipoic acid (100 mg kg−1) was administered daily as an oral supplement. The rats were exercised in a graded manner for 5 d wk−1. The concentration of MDA in the soleus and red gastrocnemius was significantly lower in rats that exercised and received LA than in the other groups. Compared with the other groups, rats that exercised and received LA had a significantly higher vitamin E concentration in the soleus. The SOD and GPx activities in the soleus and red gastrocnemius were significantly higher in rats that exercised and received LA. These results suggest that LA supplementation combined with aerobic treadmill exercise inhibits lipid peroxidation in skeletal muscles. This effect was especially remarkable in the soleus, which is particularly sensitive to oxidative stress, as revealed by the increased vitamin E level and SOD and GPx activities. 相似文献
52.
Monoliths with chiral surface functionalization for enantioselective capillary electrochromatography
The state-of-the-art in CEC enantiomer separations with monolithic capillary columns is comprehensively reviewed. The various types of monolithic columns comprising in situ organic polymer monoliths, molecularly imprinted polymer (MIP) monoliths, silica monoliths and monoliths made from particles are discussed with a focus on materials’ synthesis, chemistry and properties as well as column aspects. Monolithic MIP-type porous layer open-tubular (PLOT) columns are treated herein as well. From this survey of the literature, the authors come to the conclusion that monolithic silica capillaries appear to become the preferred column type for CEC enantiomer separations of low-molecular drugs and other chiral pharmaceuticals or chemicals. 相似文献
53.
三种回归方法计算半数致死烧伤面积结果的比较 总被引:2,自引:0,他引:2
目的 寻找一种较为合理的半数致死烧伤面积 (LA50 )回归计算法。 方法 采用线性回归、概率型概率单位回归和逻辑型概率单位回归 3种方法 ,分别计算不同烧伤样本的LA50 及LA50的 95 %可信区间 (95 %CI) ,比较各方法的计算结果。 结果 同一样本经 3种方法计算 ,LA50 值相同、不同或差异明显 ,但LA50 高低排序顺位结果一致 (P >0 .0 5 )。 3种方法计算各样本LA50 值的95 %CI,其结果比较 ,差异有非常显著性意义 (P <0 .0 1) ;线性回归法的 95 %CI分别与两型概率单位回归法的 95 %CI相比较 ,差异有非常显著性意义 (P <0 .0 1) ;两型概率单位回归法的 95 %CI相比较 ,差异无显著性意义 (P >0 .0 5 )。 结论 样本LA50 和 95 %CI的计算结果可因计算方法不同而异。只有采用同一方法、同一计算类型 ,LA50 值之间才具可比性。从计算的简便、实用性和减少抽样误差等方面考虑 ,3种方法中以逻辑型概率单位回归为最佳 相似文献
54.
Conjugated linoleic acid (CLA) refers to a group of biologically active fatty acids that exhibit anticarcinogenic properties; however, the mechanism of action remains poorly understood. Caveolae are specialized plasma membrane structures that affect many facets of cancer cell function, including growth, cell signaling, and apoptosis. Therefore, one potential mechanism could be alteration of caveolae lipid composition and function. We hypothesized that CLA can alter the lipid microenvironment of caveolae and alter expression of the major caveolae-resident protein, caveolin-1. MCF-7 human breast cancer cells were treated with a vehicle control, linoleic acid (LA), or CLA for 3 days after which total cell lysate, plasma membrane, and caveolae membrane fractions were isolated. Our findings indicate that CLA readily incorporates into caveolae (Δ9cis,11trans-18:2 being the major isomer) and maybe preferentially enriched in specific phospholipid species. Furthermore, caveolin-1 localization to caveolae after treatment with CLA was decreased relative to either control- or LA-treated cells, without changes in total cellular levels of protein relative to vehicle-control treated cells. Taken together, our results suggest that further investigation of a potential therapeutic role for CLA in modulating caveolae function in breast cancer is merited. 相似文献
55.
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57.
Akihisa Kataoka Xin Zeng J. Luis Guerrero Adam Kozak Gavin Braithwaite Robert A. Levine Gus J. Vlahakes Judy Hung 《The Journal of thoracic and cardiovascular surgery》2018,155(4):1485-1493
Objectives
Ischemic mitral regurgitation (IMR) results from ischemic left ventricular (LV) distortion and remodeling, which displaces the papillary muscles and tethers the mitral valve leaflets apically. The aim of this experimental study was to examine efficacy of an adjustable novel polymer filled mesh (poly-mesh) device to reverse LV remodeling and reduce IMR.Methods
Acute (N = 8) and chronic (8 weeks; N = 5) sheep models of IMR were studied. IMR was produced by ligation of circumflex branches to create myocardial infarction. An adjustable poly-mesh device was attached to infarcted myocardium in acute and chronic IMR models and compared with untreated sham sheep. Two- and 3-dimensional echocardiography and hemodynamic measurements were performed at baseline, post IMR, and post poly-mesh (humanely killed).Results
In acute models, moderate IMR developed in all sheep and decreased to trace/mild (vena contracta: 0.50 ± 0.09 cm to 0.26 ± 0.12 cm; P < .01) after poly-mesh. In chronic models, IMR decreased in all sheep after poly-mesh, and this reduction persisted over 8 weeks (vena contracta: 0.42 ± 0.09 cm to 0.08 ± 0.12 cm; P < .01) with significant increase in the slope of end-systolic pressure–volume relationship (1.1 ± 0.5 mm Hg/mL to 2.9 ± 0.7 mm Hg/mL; P < .05). There was a significant reduction in LV volumes from chronic IMR to euthanasia stage with poly-mesh compared with sham group (%end-diastolic volume change ?20 ± 11 vs 15% ± 16%, P < .01; %end-systolic volume change ?14% ± 19% vs 22% ± 22%, P < .05; poly-mesh vs sham group) consistent with reverse remodeling.Conclusions
An adjustable polymer filled mesh device reduces IMR and prevents continued LV remodeling during chronic follow-up. 相似文献58.
Quyen D. Chu Meijiao Zhou Prakash Peddi Kaelen L. Medeiros Xiao-Cheng Wu 《Surgery》2018,163(6):1213-1219
Background
The Cancer and Leukemia Group B 9,343 demonstrated that postoperative radiation can be safely omitted in women ≥70 years who underwent breast-conserving therapy for clinical stage I (T1N0M0) estrogen receptor positive breast cancer treated with antihormonal therapy. Whether such results are observed in real-world population is unknown. In this hospital-based data, we report the survival outcomes of patients who received adjuvant radiation therapy versus those who did not.Methods
Using the National Cancer Data Base, we evaluated a cohort of 47,358 women with newly diagnosed breast cancer between 2004 and 2011 who underwent a lumpectomy and antihormonal therapy with the following criteria: age ≥70 years, clinical stage I, estrogen receptor positive, and negative margins. Patients were stratified into 2 groups: (1) radiation therapy and (2) no radiation therapy. Propensity score matching was used to compensate for differences in demographic and clinical characteristics of the patients. Univariate and multivariable survival analysis were employed to determine factors associated with overall survival.Results
The 5-year overall survival after propensity score matching was 87.2% for radiation therapy and 79.4% for no radiation therapy (P?<?.0001). The median survival time was 113.7 months for radiation therapy and 105.2 months for no radiation therapy. After adjusting for sociodemographic and clinical factors, the risk of overall deaths was significantly higher for those not receiving radiation therapy (hazard ratio?=?1.66; 95% confidence interval, 1.54–1.79). Other significant adjusted predictors (P?<?.05) of poor overall survival were, advanced age, comprehensive community cancer program, facility location, poorly differentiated tumor, and high comorbidity index.Conclusion
Patients who received radiation therapy had better survival outcomes than those who did not, revealing discordance between results of randomized trials and real-world setting. 相似文献59.
Sanmarco M Roll P Gayet S Oksman F Johanet C Escande A Cohen JH Chevailler A Goetz J Humbel RL Sibilia J 《The Journal of laboratory and clinical medicine》2004,144(3):141-147
In this study we sought to assess (1) the diagnostic value of a combined search for anti-beta(2)-glycoprotein (abeta(2)-GPIs) and anticardiolipin antibodies (aCLs) in primary (APS I) and secondary (APS II) antiphospholipid syndrome and (2) the influence of the beta(2)-GPI preparation in the ELISA's results. abeta(2)-GPI and aCL concentrations were assessed in 70 patients with APS and compared with those in 65 patients with systemic lupus erythematosus (SLE) without clinical features of APS. In APS patients (38 with APS I, 32 with APS II), the diagnosis had to have been made at least 3 years earlier; in subjects with SLE, the diagnosis had to have been made at least 5 years earlier. All serum samples were tested for abeta(2) -GPI with the use of an in-house ELISA with an abeta(2) -GPI preparation from human plasma. Samples negative for abeta(2) -GPI were controlled with 2 additional beta(2)-GPI preparations, 1 from human serum and 1 from bovine serum. In APS, abeta(2)-GPIs were more frequent than in SLE (76% and 15%, respectively; P <.0001), mainly with IgG isotype and with significantly higher levels than those found in SLE. The specificity for APS was 92% for IgG abeta(2)-GPIs and 68% for IgG aCLs. The highest association with APS was found for the combination of the 2 markers (odds ratio 29; 95% confidence interval 10-76; P <.0001). Among the APS patients, 6 were positive for aCL only and remained negative regardless of which beta 2 -GPI preparation was used; 1 patient was aCL-negative and only positive with human beta 2 -GPI. These data emphasize the heterogeneity of the APS immunologic profile and the diagnostic possibilities of both antibodies. 相似文献
60.
N. H. Toumi F. Khaldi S. Ben Becheur A. Hammou B. Bouttière J. Sampol K. Boukef 《Hematology and Cell Therapy》1998,39(6):295-299
Abstract. Congenital deficiency in coagulation inhibitors is a cause of hereditary thrombotic disease. The severity of symptoms is variable and depends on the type of deficit. In this paper, 44 children suffering from deep venous thrombosis, with a mean age of 5 years, were studied. A search for Lupus anticoagulant (LA) and coagulation inhibitor deficiency showed: 3/44 cases (6.8%) had protein S deficiency, 2/44 cases (4.5%) had protein C deficiency, 1/44 cases (2.3%) had deficiencies in both protein C and S; no cases of AT III deficiency and LA was positive in 2/44 cases (4.5%). Only 1 case of APC resistance out of 13 studied was found. Four family studies were performed and confirmed the congenital origin of the disorder. 相似文献