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991.
目的:探讨聚丙烯酰胺水凝胶注射隆胸后取出新方法.方法:对48例注射聚丙烯酰胺水凝胶隆胸患者术前行双乳MRI或彩超检查结合触诊准确定位.全麻小切口开放直视下吸出水凝胶,再用大量生理盐水反复灌洗所有腔隙,直至手感探测不到硬结,盐水中无水凝胶为止.结果:48例患者术后无继发感染和出血等并发症.术前诸症状体征消失,无明显乳房变形,乳房形态术后恢复满意.术后双乳MRI复查未见明显异物残留.术后1 ~12月(6.2±0.3月)45例随访复查MRI亦未见异物残留,乳房修复完好.结论:注射隆乳后腔内大量盐水灌洗辅助取出水凝胶具有创伤小、出血少、操作简单、费用低廉的优点,是一种较好的、值得推广的凝胶取出术式.  相似文献   
992.
993.
Patients with age related macular degeneration (AMD) will develop vision loss in the center of the visual field. Reactive oxygen species (ROS)-mediated retinal pigment epithelium (RPE) cell apoptosis is an important contributor of AMD. In this study, we explored the pro-survival effect of α-melanocyte stimulating hormone (α-MSH) on oxidative stressed RPE cells. We found that α-MSH receptor melanocortin 1 receptor (MC1R) was functionally expressed in primary and transformed RPE cells. RPE cells were response to α-MSH stimulation. α-MSH activated Akt/mammalian target of rapamycin (mTOR) and Erk1/2 signalings in RPE cells, which were inhibited by MC1R siRNA knockdown. α-MSH protected RPE cells from hydrogen peroxide (H2O2)-induced apoptosis, an effect that was almost abolished when MC1R was depleted by siRNA. α-MSH-mediated S6K1 activation and pro-survival effect against H2O2 was inhibited by Akt inhibitors (perifosine, MK-2206 and LY294002). Further, mTOR inhibition by rapamycin, or by mTOR siRNA knockdown, diminished α-MSH’s pro-survival effect in RPE cells. Thus, Akt and its downstream mTOR signaling mediates α-MSH-induced survival in RPE cells. In summary, we have identified a new α-MSH–MC1R physiologic pathway that reduces H2O2-induced RPE cell damage, and might minimize the risk of developing AMD.  相似文献   
994.
It is known that pharmacological or toxic doses of vitamin D induce bone resorption both in vivo and in vitro, whereas physiological doses of the vitamin have a protective effect on bone in vivo. To investigate the discrepancies of the dose-dependent effect of vitamin D on bone resorption, we examined the in vivo effect of 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] on the expression of the receptor activator of nuclear factor-kappaB (NF-kappaB) ligand (RANKL) and osteoprotegerin (OPG) mRNAs in bone of thyroparathyroidectomized (TPTX) rats infused with or without parathyroid hormone (PTH). Continuous infusion of 50 ng/h of PTH greatly increased the expression of RANKL mRNA in bone of TPTX rats. Expression of OPG mRNA was not altered by PTH infusion. When graded doses of 1,25(OH)(2)D(3) was daily administered orally for 14 days to normocalcemic TPTX rats constantly infused with PTH, 0.01 and 0.1 microg/kg of 1,25(OH)(2)D(3) inhibited the PTH-induced RANKL mRNA expression, but 0.5 microg/kg of the vitamin did not inhibit it. Regulator of G protein signaling-2 (RGS-2) gene expression was suppressed by 1,25(OH)(2)D(3) dose-dependently, but PTH/PTHrP receptor mRNA expression was not altered. Bone morphometric analyses revealed that 1,25(OH)(2)D(3) suppressed PTH-induced osteoclast number in vivo. These results suggest that pharmacological or toxic doses of 1,25(OH)(2)D(3) stimulate bone resorption by inducing RANKL, but a certain range of physiological doses of the vitamin inhibit PTH-induced bone resorption, the latter mechanism appeared to be mediated, at least in part, by the suppression of the PTH/PTHrP receptor-mediated signaling.  相似文献   
995.
Turnover of glucose and acetate in the presence of active reduction of nitrate, ferric iron and sulfate was investigated in anoxic rice field soil by using [U-(14)C]glucose and [2-(14)C]acetate. The turnover of glucose was not much affected by addition of ferrihydrite or sulfate, but was partially inhibited (60%) by addition of nitrate. Nitrate addition also strongly reduced acetate production from glucose while ferrihydrite and sulfate addition did not. These results demonstrate that ferric iron and sulfate reducers did not outcompete fermenting bacteria for glucose at endogenous concentrations. Nitrate reducers may have done so, but glucose fermentation may also have been inhibited by accumulation of toxic denitrification intermediates (nitrite, NO, N(2)O). Addition of nitrate resulted in complete inhibition of CH(4) production from [U-(14)C]glucose and [2-(14)C]acetate. However, addition of ferrihydrite or sulfate decreased the production of (14)CH(4) from [U-(14)C]glucose by only 70 and 65%, respectively. None of the electron acceptors significantly increased the production of (14)CO(2) from [U-(14)C]glucose, but all increased the production of (14)CO(2) from [2-(14)C]acetate. Uptake of acetate was faster in the presence of either nitrate, ferrihydrite or sulfate than in the unamended control. Addition of ferrihydrite and sulfate reduced (14)CH(4) production from [2-(14)C]acetate by 83 and 92%, respectively. Chloroform completely inhibited the methanogenic consumption of acetate. It also inhibited the oxidation of acetate, completely in the presence of sulfate, but not in the presence of nitrate or ferrihydrite. Our results show that, besides the possible toxic effect of products of nitrate reduction (NO, NO(2)(-) and N(2)O) on methanogens, nitrate reducers, ferric iron reducers and sulfate reducers were active enough to outcompete methanogens for acetate and channeling the flow of electrons away from CH(4) towards CO(2) production.  相似文献   
996.
应用HCVC (pC)和HCVCE1E2 (pCE1E2 )重组体转染真核细胞并且通过肌注免疫BALB/C小鼠 ,对其体液免疫和细胞免疫进行检测。所用的 pC和 pCE1E2 均可在真核细胞内表达出特异性HCVC蛋白 ;肌注DNA免疫后均可诱导出BALB/C小鼠的体液和细胞免疫反应 ,抗体反应的A值 :pC组为 0 .358± 0 .0 96 ,pCE1E2 组为 0 .4 15± 0 .12 7;CTL活力 pC组为 18.6 5%± 5.72 % ,pCE1E2 组为 2 0 .0 7%± 11.11% ;通过免疫鼠荷瘤检测体内CTL反应 ,可观察到免疫组鼠发瘤时间滞后 ,发瘤部位减少和存活时间延长。在开发和研制HCV疫苗的过程中 ,DNA免疫是在快速构建、评价和筛选免疫原方面的有效办法。  相似文献   
997.
998.
Lipid droplets (LDs) are ubiquitous cellular organelles for lipid storage which are composed of a neutral lipid core bounded by a protein decorated phospholipid monolayer. Although lipid storage is their most obvious function, LDs are far from inert as they participate in maintaining lipid homeostasis through lipid synthesis, metabolism, and transportation. Furthermore, they are involved in cell signaling and other molecular events closely associated with human disease such as dyslipidemia, obesity, lipodystrophy, diabetes, fatty liver, atherosclerosis, and others. The last decade has seen a great increase in the attention paid to LD biology. Regardless, many fundamental features of LD biology remain obscure. In this review, we will discuss key aspects of LD biology including their biogenesis, growth and regression. We will also summarize the current knowledge about the role LDs play in human disease, especially from the perspective of the dynamics of the associated proteins. This article is part of a Special issue entitled Cardiac adaptations to obesity, diabetes and insulin resistance, edited by Professors Jan F.C. Glatz, Jason R.B. Dyck and Christine Des Rosiers.  相似文献   
999.
我国各类基物上的酵母菌分布及其尿素酶活性   总被引:2,自引:0,他引:2  
本文讨论了2300株由我国各地分离到的酵母菌和类酵母菌与各类基物的关系。共述及23属,占Lodder(1970)系统的半数以上。在十几类基物中酵母菌的分布各有不同,叶子上有大量掷孢酵母,果实上比其它基物更能获得克勒克酵母属(Kloeckera),在咸腌食品中相对地有较多耐高渗透压的酵母如球拟酵母属(Torulopsis)与德巴利酵母属(Debaryomyces)。对部分属的定种工作也已进行,说明某些属的种在我国均有发现而且为数不少。此外还研究了600余株代表各类酵母的尿素酶活性,结果说明担子菌酵母或系统上接近担子菌的酵母都有尿素酶活性,而子囊菌酵母则无。根据作者的观察子囊菌酵母中裂殖酵母属(Schizosaccharomyces)则常常例外地有尿素酶反应,且常有辅酶Q_(10),从而可见裂殖酵母属有其特有的生物学特性,在系统上很可能与其它子囊菌酵母不同。对属于不完全菌的无孢子酵母也进行了尿素酶活性测定,结果表明它们部分与子囊菌有关,部分与担子菌有关。  相似文献   
1000.
A method of the competitive immunochromatographic assay of the pesticides 2,4-D (2,4-dichlorophenoxyacetic acid) and simazine (2-chloro-4,6-bis(N-ethylamino)-1,3,5-triazine) in aqueous samples was developed. Monoclonal antibodies to these pesticides labeled with colloidal gold were used to visualize the results. The sensitivity of the 2,4-D and simazine assay is 12 ng/ml, and the time of analysis is 3–7 min. The method does not differ in sensitivity from the competitive EIA using conjugates of monoclonal antibodies to the pesticides with horseradish peroxidase; however, the time of the EIA is 1.5 h. The immunochromatographic method of the pesticide detection is available and simple and may be recommended for the development of assays of any other low-molecular compounds.  相似文献   
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