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1.
《Nutrition, metabolism, and cardiovascular diseases : NMCD》2022,32(12):2883-2889
Background and aimsCoronary artery disease (CAD) is the principal cause of death in individuals with non-alcoholic fatty liver disease (NAFLD). The aim of this study was to use genetic epidemiology to study the association between de novo lipogenesis (DNL), one of the major pathways leading to NAFLD, and CAD risk.Methods and resultsDNL susceptibility genes were used as instruments and selected using three approaches: 1) genes that are associated with both high serum triglycerides and low sex hormone-binding globulin, both downstream consequences of DNL (unbiased approach), 2) genes that have a known role in DNL (biased approach), and 3) genes that have been associated with serum fatty acids, used as a proxy of DNL. Gene-CAD effect estimates were retrieved from the meta-analysis of CARDIoGRAM and the UK Biobank (~76014 cases and ~264785 controls). Effect estimates were clustered using a fixed-effects meta-analysis. Twenty-two DNL susceptibility genes were identified by the unbiased approach, nine genes by the biased approach and seven genes were associated with plasma fatty acids. Clustering of genes selected in the unbiased and biased approach showed a statistically significant association with CAD (OR:1.016, 95%CI:1.012; 1.020 and OR:1.013, 95%CI:1.007; 1.020, respectively), while clustering of fatty acid genes did not (OR:1.004, 95%CI:0.996–1.011). Subsequent exclusion of potential influential outliers did reveal a statistically significant association (OR:1.009, 95%CI:1.000; 1.018).ConclusionsDNL susceptibility genes are associated with an increased risk of CAD. These findings suggest that DNL may be involved in the pathogenesis of CAD and favor further development of strategies that target NAFLD through DNL. 相似文献
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3.
Reactive oxygen species and human spermatozoa: physiology and pathology 总被引:20,自引:1,他引:19
The role of reactive oxygen species (ROS) in the pathophysiology of human sperm function has been emphasized in recent years. ROS production in semen has been associated with loss of sperm motility, decreased capacity for sperm–oocyte fusion and loss of fertility. There is a current presumption that the most prolific source of ROS in sperm suspensions is an NADPH oxidase located in leukocytes or in spermatozoa which produces superoxide which is further converted to peroxide by the action of superoxide dismutase. Hydrogen peroxide has been recognized as the most toxic oxidizing species for human spermatozoa, which are very sensitive to lipid peroxidation owing to the high content of polyunsaturated fatty acids in their plasma membrane, though this is not the sole mechanism by which sperm function might be impaired by ROS. Although the excessive production of ROS is detrimental to human spermatozoa, there is a growing body of evidence which suggests that ROS are also involved in the physiological control of some sperm functions. This review focuses on the nature and source of the ROS generated by human spermataozoa as well as their operational mechanisms and their effects, which may be detrimental or beneficial. 相似文献
4.
5.
Teng-Yi Huang Hsiao-Wen Chung Fu-Nien Wang Cheng-Wen Ko Cheng-Yu Chen 《Magnetic resonance in medicine》2004,51(2):243-247
In this work the feasibility of separating fat and water signals using the balanced steady-state free precession (SSFP) technique is demonstrated. The technique is based on the observation (Scheffler and Hennig, Magnetic Resonance in Medicine 2003;49:395-397) that at the nominal values of TE = TR/2 in SSFP imaging, phase coherence can be achieved at essentially only two orientations (0 degrees and 180 degrees ) relative to the RF pulses in the rotating frame, under the assumption of TR < T2, and independently of the SSFP angle. This property allows in-phase and out-of-phase SSFP images to be obtained by proper choices of the center frequency offset, and thus allows the Dixon subtraction method to be utilized for effective fat-water separation. The TR and frequency offset for optimal fat-water separation are derived from theories. Experimental results from healthy subjects, using a 3.0 Tesla system, show that nearly complete fat suppression can be accomplished. 相似文献
6.
In this study, the effect of regular khat (Catha edulis Forsk) chewing (200 and 400 g) in humans on plasma leptin, nonesterified fatty acid, triacyglycerol, and total cholesterol levels was investigated. The results presented show that khat chewing increases plasma leptin concentration particularly in individuals who chew 400 g of khat leaves. The significance of increased plasma leptin is in explaining the underlying mechanism of the observed effects associated with khat chewing such as loss of appetite, decreased body weight, and hyperthermia. The decreased body weight was evident from the significantly lower body mass index of the khat leaves chewers group as compared to the non–khat leaves chewers group (control). Moreover, like leptin, the plasma levels of nonesterified fatty acids were significantly higher in those chewing 400 g of khat leaves. On the other hand, the plasma levels of triacylglycerol were significantly lower in the 2 khat-chewers groups (200 and 400 g of khat leaves), whereas plasma cholesterol levels were not affected by the 2 levels of khat leaves used in this study. The significance of these results may suggest that khat leaves may contain a component(s) that has the ability to reduce body weight via decreasing appetite. 相似文献
7.
目的:提高前臂预成皮瓣整复术的护理水平.方法:通过术前心理护理,供区的皮肤保护,口腔装备,术后环境准备和卧位,皮瓣观察,切口护理,饮食和口腔护理进行评价.结果:预成皮瓣正常成活,色泽红润如期修复腭部缺损.结论:良好的护理可以提高前臂预成瓣移植的成功率. 相似文献
8.
R.J.W. de Keizer 《International ophthalmology》1997,21(6):335-341
In a prospective study the results of a pterygium excision in 54 patients (57 eyes) who underwent a superficial free conjunctival
autograft (FCG) were compared to those of patients who were treated with postoperative90Sr-irradiation. In 51 cases the minimum
follow-up was six months, the maximum follow-up seven years. We divided the study up into a randomized part and an open part.
In the randomized part, surgery of a primary pterygium was performed in 25 eyes, of which 16 were treated with a FCG and compared
with 9 eyes with primary pterygium surgery and postoperative90Sr beta-irradiation. In the same period 16eyes were treated
because of a recurrent pterygium: 8 with FCG and 8 with90Sr-irradiation. In the open part of the study16 eyes with primary
pterygium were successively treated with FCG alone.
The results showed in the randomized, as well as in the open study on primary surgery with a minimum follow-up of six month,
one recurrence in each of the FCG-groups (2 out of 31 eyes =6.4%), and no recurrences in the 90Sr-group(0%). In the randomized
group of patients treated for a recurrent pterygium one recurrence developed in the FCG group (1 out of 8 eyes =12.5%) and
one in the 90Sr-group (1 out of 7 =14.6%). Analysis of other clinical parameters showed that postoperative treatment with
corticosteroids, nonsteroidal anti-inflammatory drugs, and artificial tears was necessary for a longer period in the FCG group
than in the90Sr-group.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
9.
本研究建立了大鼠气管上皮细胞体内-体外转化模型,大鼠气管内滴注苯并芘,三天后处死大鼠,消化气管上皮细胞,接种于无血清完全培养基。细胞形成集落后,换为选择培养基继续培养五周,统计转化率。结果显示,25mg/kg和50mg/kg的苯并芘可诱导大鼠气管上皮细胞转化及微核增加,用同样方法研究了煤焦沥青提取物,结果表明,剂量为8mg/kg和25mg/kg的煤焦沥青提取物能明显诱导大鼠气管上皮细胞转化。 相似文献
10.
Effects of androgen treatment in impotent men with normal and low levels of free testosterone 总被引:1,自引:0,他引:1
Cesare Carani M.D. Dante Zini M.D. Augusto Baldini M.D. Luciano Della Casa M.D. Anna Ghizzani M.D. Paolo Marrama M.D. 《Archives of sexual behavior》1990,19(3):223-234
The relation between sexual function and serum free testosterone (fT) levels, which represent the active fraction of circulating testosterone, was evaluated. Two groups of impotent male subjects with mild hypogonadism were treated with oral testosterone undecanoate (TU); these men presented with tT/luteinizing hormone (LH) ratio and tT levels at the lower limits of normal. The first group had serum fT below 6.6 ng/ml, considered the lower normal value, according to our laboratory method, whereas the second group had normal fT limits. Administration of TU improved sexual function only in impotent men with low fT levels, but not in subjects with normal fT levels, even though the tT levels and the tT/LH ratio of the two groups were not significantly different. The results of our study suggest the presence of a minimun serum fT threshold, lying near the lower normal range, which determines the male sexual function. Moreover, serum fT levels were a more sensitive index than tT for identifying impotent men who can be successfully treated with androgens. 相似文献