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Early microbial recognition by the innate immune system is accomplished by Toll-like receptors (TLRs), with resultant initiation of a pro-inflammatory response against infecting organisms. In spite of presence of an abundance of Toll-like receptors on the surface of the liver, gut bacteria does not elicit an inflammatory reaction in healthy individuals due to tolerance to these TLRs, suggesting that the inflammatory responses seen in the liver are the result of breakdown of this tolerance. While orthotopic liver transplantation is often life saving in many instances, death following this procedure is most commonly due to infection that occurs in up to 80% of transplant recipients, most commonly due to microbial causes in up to 70% of cases and viral infections in 20%, while fungal infections affect only 8% of cases. The probability of acquiring infection following hepatic transplantation is heightened due to affection of the innate immune defense mechanisms of the host following this procedure. Single nucleotide polymorphisms of TLRs have been associated with increased likelihood of either development of post-transplant infection or eradication of infecting organism. However, conflicting reports from other studies reveal that prevalence of this single nucleotide polymorphism is not increased in infected patients.  相似文献   
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There is a clear link between diabetes and oxidative stress. Hyperglycaemia leads to free radical generation and alteration of endogenous antioxidants. The present study is an attempt to evaluate the possible protective effect of melatonin (MLT) and/or desferrioxamine (DF) against streptozotocin (STZ)-induced hyperglycaemia in mice. Serum lipid profile, pancreatic tissue contents of glutathione (GSH) and malondialdehyde (MDA) were determined. MLT and/or DF were given p.o. in doses of 5 mg kg(-1)day(-1)and 250 mg kg(-1) day(-1), respectively for 15 consecutive days prior to STZ treatment (60 mg kg(-1) day(-1) i.p.) for 3 consecutive days. Results revealed that STZ induced a marked increase in serum glucose, serum triglycerides (TG), cholesterol (CHO) and LDL-cholesterol. On the contrary HDL-cholesterol was markedly decreased in STZ-treated group. Moreover, STZ induced a significant decrease in the pancreatic content of GSH with concomitant increase in MDA content. Administration of MLT or (MLT+DF) prior to STZ treatment revealed a marked decrease in serum glucose level by 35.6 and 31.6%, respectively as compared to STZ-treated group. Furthermore, MLT pretreatment of STZ-induced hyperglycemic mice, has not only normalized GSH content of pancreatic tissues but also increased its level more than that of control animals by 110%. On the contrary, MDA content of pancreatic tissues was markedly decreased even lower than normal control group. MLT also, induced a marked protection in terms of decreasing serum CHO, LDL, TG by 21.8, 83.8 and 82.2%, respectively, while HDL was increase by 56% as compared to STZ treated group. DF was found to be less effective than MLT in the protection against STZ-induced hyperglycemia. In conclusion, these data suggest that MLT protects against the damaging consequences induced by hyperglycemia either systemically or in the pancreatic tissues.  相似文献   
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Background  Androgenetic alopecia is a common cosmetic hair disorder, resulting from interplay of genetic, endocrine, and aging factors leading to a patterned follicular miniaturization. Microinflammation seems to be a potential active player in this process.
Aims  To study the histopathological and ultrastructural changes occurring in male androgenetic alopecia (AGA).
Patients/methods  Fifty-five subjects were included in this study (40 with AGA and 15 as normal age-matched controls). Skin biopsies from frontal bald area and occipital hairy area were subjected to histopathological examination, immunohistochemical staining for collagen I and ultrastructural study.
Results  The frontal bald area of patients showed highly significant increase in telogen hairs and decrease in anagen/telogen ratio and terminal/vellus hair ratio ( P  <   0.001). Perifollicular inflammation was almost a constant feature in early cases and showed a significant inverse correlation with perifollicular fibrosis ( P  =   0.048), which was more marked with thickening of the follicular sheath in advanced cases.
Conclusion  Follicular microinflammation plays an integral role in the pathogenesis of AGA in early cases. Over time, thickening of perifollicular sheath takes place due to increased deposition of collagen, resulting in marked perifollicular fibrosis, and sometimes ends by complete destruction of the affected follicles in advanced cases.  相似文献   
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目的:提供合适的方法,以控制梅花点舌丸的含量。方法:双波长薄层扫描法测定梅花点舌丸中华蟾蜍毒基的含量。λs=295nm,λn=370nm。在1。200-6.020μg范围内呈良好的线性(r=0.9978),同板和异板精密度试验的RSD值分别为0.092%主2.79%(n=5)。结果:平均加样回收率和RSD值分别为99.2%和1.14%(n=6),结论:本法简单、准确、可作为梅花点舌丸的质量控制方法。  相似文献   
139.
BackgroundThe randomized SOLVE-TAVI (compariSon of secOnd-generation seLf-expandable vs. balloon-expandable Valves and gEneral vs. local anesthesia in Transcatheter Aortic Valve Implantation) trial compared newer-generation self-expanding valves (SEV) and balloon-expandable valves (BEV) as well as local anesthesia with conscious sedation (CS) and general anesthesia (GA) in patients undergoing transfemoral transcatheter aortic valve replacement (TAVR). Both strategies showed similar outcomes at 30 days.ObjectivesThe purpose of this study was to compare clinical outcomes during 1-year follow-up in the randomized SOLVE-TAVI trial.MethodsUsing a 2 × 2 factorial design 447 intermediate- to high-risk patients with severe, symptomatic aortic stenosis were randomly assigned to transfemoral TAVR using either the SEV (Evolut R, Medtronic Inc., Minneapolis, Minnesota) or the BEV (Sapien 3, Edwards Lifesciences, Irvine, California) as well as CS or GA at 7 sites.ResultsIn the valve-comparison strategy, rates of the combined endpoint of all-cause mortality, stroke, moderate or severe paravalvular leakage, and permanent pacemaker implantation were similar between the BEV and SEV group (n = 84, 38.3% vs. n = 87, 40.4%; hazard ratio: 0.94; 95% confidence interval: 0.70 to 1.26; p = 0.66) at 1 year. Regarding the anesthesia comparison, the combined endpoint of all-cause mortality, stroke, myocardial infarction, and acute kidney injury occurred with similar rates in the GA and CS groups (n = 61, 25.7% vs. n = 54, 23.8%; hazard ratio: 1.09; 95% confidence interval: 0.76 to 1.57; p = 0.63).ConclusionsIn intermediate- to high-risk patients undergoing transfemoral TAVR, newer-generation SEV and BEV as well as CS and GA showed similar clinical outcomes at 1 year using a combined clinical endpoint. (SecOnd-generation seLf-expandable Versus Balloon-expandable Valves and gEneral Versus Local Anesthesia in TAVI [SOLVE-TAVI]; NCT02737150)  相似文献   
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长梗南五味子化学成分的研究   总被引:10,自引:0,他引:10  
从长梗南五味子(Kadsura longepedunculata)根中分离出一个新化合物,经光谱和化学方法证明为南五内酯酸(kadsulactoneacid,I),同时还分离得到5个已知化合物:南五内酯(I)、(+)-安五脂素(II)、二氢愈疮木脂素(IV)、d-表加巴辛(V)和β-谷甾醇(VI)。  相似文献   
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