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431.
In a patient with choledocholithiasis, a duodenal diverticulum precluded endoscopic retrograde bile duct cannulation. A transhepatic catheter was used to opacify the bile ducts and to guide the endoscopic sphincterotome into the major duodenal papilla. Because limited sphincterotomy did not allow extraction or spontaneous passage of the common duct stones, extracorporeal lithotripsy was performed. Following fragmentation, the stones passed spontaneously and without complications. 相似文献
432.
Estimation of aneuploidy for chromosomes 3, 7, 16, X and Y in spermatozoa from 10 normospermic men using fluorescence in-situ hybridization 总被引:3,自引:0,他引:3
Fluorescence in-situ hybridization (FISH) is a fast and efficient method of
estimating aneuploidy in human spermatozoa. In this study, we have
estimated baseline disomy frequencies in spermatozoa from a group of 10
normospermic men, using stringent scoring criteria. A triple- probe FISH
procedure was used for chromosomes 3, X and Y, while a double-probe FISH
method was used for chromosomes 7 and 16. A total of 101273 spermatozoa
were scored for chromosomes 3, X and Y, resulting in 97.83% haploidy (3X or
3Y), 0.39% disomy (33X, 33Y, 3XX, 3YY or 3XY) and 0.35% diploidy (33XX,
33YY or 33XY). A total of 100760 spermatozoa were scored for chromosomes 7
and 16, giving 98.9% haploidy (716), 0.11% disomy (7716 or 71616) and 0.27%
diploidy (771616). Disomy frequencies for individual chromosomes differed
(chromosome 3, 0.20%; chromosome 7, 0.05%, chromosome 16, 0.06%; X + Y,
0.19%). The frequency of disomy 3 was significantly higher than disomy 7 (P
= 0.019) and disomy 16 (P = 0.022), while the frequency of sex chromosome
disomy was significantly higher than disomy 7 (P = 0.0058) and disomy 16 (P
= 0.0067), but not disomy 3 (P = 0.73). The disomy and diploidy (0.27-
0.35%) estimates obtained for this normospermic population were generally
low and were similar to other recent reports.
相似文献
433.
Of 22 subjects previously reported with some form of factor H dysfunction, 12 had a glomerulonephritis that appeared to not be of immune complex origin. Factor H dysfunction results in elevated circulating levels of the C3b-dependent C3 convertase, C3b,Bb. Of the 12 cases with glomerulonephritis, the glomerular deposits in the six whose biopsy specimens were studied were predominately subepithelial on the paramesangial portion of the glomerular basement membrane. In a subsequent study, similar deposits were found in patients with membranoproliferative glomerulonephritis (MPGN) type II, also a nephritis that is probably not of immune complex origin. Paramesangial deposits were found in these patients only in biopsy specimens obtained when the C3 level was low, at which time convertase stabilized by nephritic factor would be present in the circulation. This association of paramesangial deposits with circulating convertase was further tested by correlating these deposits with the level of C3 at the time of biopsy in MPGN types I and III. The results in type III MPGN were similar to those in type II; paramesangial deposits were frequently present when the C3 level was low as a result of circulating nephritic factor of the terminal pathway, NFt, and were usually absent when the C3 level was in the upper two thirds of the normal range. Deposits persisted in those patients with C3 levels that had been low but that had increased during the year before biopsy to within the lower one third of the normal range. The persistence of paramesangial deposits in MPGN type III, as compared with MPGN type II, may be related to the differences in composition and function of the two NF stabilized convertases (C3bn,Bb,P,NFt and C3b,Bb,NFa, respectively) that circulate in these two disorders. In contrast to MPGN type III, the hypocomplementemia in MPGN type I is thought to be, for the most part, the result of classical pathway activation, which is not associated with elevated circulating convertase levels. In agreement with this, paramesangial deposits were found in only two of 34 biopsy specimens. At the time of those two biopsies, both patients had a complement profile indicating that the NFt was circulating, as in MPGN type III. In three other cases with profiles compatible with circulating NFt, paramesangial deposits were not found. In all patients with type I MPGN, electron microscopy and immunofluorescence of the glomeruli gave results typical of an immune complex nephritis. Thus, even though the complement profile in MPGN type I may at times indicate the presence of a nephritic factor, circulating immune complexes appear to be basic to pathogenesis. The observations support the hypothesis that elevated levels of the C3b-dependent convertase, as found in the "experiments of nature" with factor H dysfunction and in MPGN types II and III, are associated with paramesangial deposits. The nature of this association and the role of these deposits in producing the nephritis is not clear. 相似文献
434.
目的:收集体外培养、纯化的骨髓间质干细胞条件培养液,检测其对多巴胺能神经元有保护作用的胶质源性神经生长因子分泌情况,并观察对1-甲基4-苯基吡啶离子诱导的PC12细胞凋亡的保护作用。方法:实验于2005-05/2006-10在中国医科大学附属一院神经内科实验室完成。①PC12细胞由协和医科大学细胞培养中心提供。1-甲基4-苯基吡啶离子(Sigma,USA,批号3707312)。②选取清洁级SD大鼠20只,麻醉后取股骨和胫骨,去净肌肉取骨髓,按1010L-1接种于含体积分数为0.2胎牛血清的低糖型DMEM培养基中,通过弃悬浮细胞及换液后可得到较纯的骨髓间质干细胞。培养第10天胰蛋白酶消化传代,当第2代细胞扩增至铺满瓶底80%时,改用含体积分数为0.05胎牛血清的低糖型DMEM条件培养液,48h后收集培养液,经超滤浓缩系统(截留分子量为10000)浓缩10倍后过滤除菌。③骨髓间充质干细胞接种于24孔板内,贴壁后多聚甲醛固定,磷酸盐缓冲液漂洗,免疫荧光法鉴定骨髓间充质干细胞表面抗原的表达。骨髓间充质干细胞消化后进行细胞计数,按1×108L-1接种于75cm培养瓶,加入含体积分数为0.2胎牛血清的DMEM培养液20mL,于培养第5,10天采用ELISA法测定细胞培养上清液中的胶质源性神经生长因子含量。④PC12细胞置于RPMI1640培养液中,内含体积分数为0.1的马血清和0.05的胎牛血清,汇集至80%时进行传代接种,液氮罐中贮存备用。实验前首先置换培养液,使血清浓度降至为仅含0.01马血清和0.01胎牛血清,24h后将培养的细胞分为4组:空白对照组,在细胞培养体系中不加入任何药物;骨髓间充质干细胞上清液组,接种后24h在细胞培养体系中分别加入骨髓间充质干细胞上清液30,60,120μL;1-甲基4-苯基吡啶离子组,接种后24h分别加入1-甲基4-苯基吡啶离子,使终浓度分别为100,200,400μmol/L;联合组,接种后24h加入200μmol/L1-甲基4-苯基吡啶离子,24h后再分别给予骨髓间充质干细胞上清液30,60,120μL。⑤各组细胞于给药后24,48h,流式细胞术检测PC12细胞的凋亡率;通过免疫细胞化学法和RT-PCR法检测PC12细胞半胱氨酸天冬氨酸蛋白酶3蛋白和mRNA的表达。结果:①骨髓间充质干细胞表面抗原鉴定:骨髓间充质干细胞可在体外分离扩增,其表面抗原CD45呈阴性,而CD44表达阳性。②骨髓间充质干细胞培养上清液中胶质源性神经生长因子水平检测:第5,10天培养上清液中的胶质源性神经生长因子浓度为(44.57±5.96)ng/L和(45.41±6.33)ng/L,差异无显著性意义(P>0.05)。③PC12细胞凋亡情况:联合组200μmol/L1-甲基4-苯基吡啶离子作用PC12细胞24h后,细胞凋亡率为(42.34±3.21)%;加入30,60,120μL骨髓间充质干细胞上清液处理24h后,细胞凋亡率分别降为(31.96±2.89)%,(17.89±1.78)%,(10.08±0.91)%,差异有显著性意义(P<0.05)。联合组药物作用48h与24h情况相似。④给药后各组半胱氨酸天冬氨酸蛋白酶3蛋白及mRNA的表达:联合组半胱氨酸天冬氨酸蛋白酶3蛋白和mRNA水平均明显低于1-甲基4-苯基吡啶离子组(t=0.05~0.32,P均<0.05)。结论:骨髓间充质干细胞能够分泌胶质源性神经生长因子,对1-甲基4-苯基吡啶离子诱导的PC12细胞凋亡产生保护作用。这种保护作用的强弱与其浓度有关,具体作用机制可能是通过抑制半胱氨酸天冬氨酸蛋白酶3蛋白和mRNA水平实现的。 相似文献
435.
436.
437.
438.
Hereditary hair loss and the ancient signaling pathways that regulate ectodermal appendage formation
CD Van Raamsdonk 《Clinical genetics》2009,76(4):332-340
All epidermal appendages, including hair, teeth, and nails, begin as a thickening of the ectoderm, called a placode. The placode arises from a primary induction signal that is sent from the underlying mesenchyme to the overlying epidermis. In mammals, the precise arrangement of hair follicles in the skin is due to the amount and distribution of signals that promote and inhibit hair placode formation. Continued development of a hair follicle after placode formation requires a complex cross-talk between the mesenchyme and epidermis. Here, I will review recent studies in humans and mice that have increased our understanding of the role of these signaling pathways in normal development and in hereditary hair loss syndromes. The study of normal hair development may suggest ways to restore or eliminate hair and might identify possible targets for the therapy of basal cell carcinoma, a cancer which strongly resembles embryonic hair follicles. 相似文献
439.
PEPDar: A randomized prospective noninferiority study of ritonavir‐boosted darunavir for HIV post‐exposure prophylaxis
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G Fätkenheuer H Jessen A Stoehr N Jung AB Jessen T Kümmerle M Berger JR Bogner CD Spinner C Stephan O Degen R Vogelmann P Spornraft‐Ragaller E Schnaitmann B Jensen A Ulmer JM Kittner G Härter P Malfertheiner J Rockstroh G Knecht S Scholten T Harrer WV Kern B Salzberger D Schürmann B Ranneberg 《HIV medicine》2016,17(6):453-459
440.
Maria J. Giraldez Carlos García‐Resúa Madalena Lira M Elisabete CD Real Oliveira Eva Yebra‐Pimentel 《Ophthalmic & physiological optics》2010,30(3):289-297
Purpose: The aim of this study was to characterize, qualitatively and quantitatively, the surface morphology of four unworn conventional hydrogel contact lenses (Omafilcon, Hioxifilcon‐based, Nefilcon A and Ocufilcon B) by White Light Optical Profiling (WLOP). WLOP is an ideal technique for sampling larger areas as well as for higher measurement speed compared with other topography techniques used in contact lens studies. Methods: Surface roughness was assessed by WLOP in the Vertical Scanning Mode, with a Wyko® NT1100, which is a non‐contact optical profiling system that provides high vertical resolution. Representative roughness parameters, the Average Roughness (Ra), Root‐mean‐square Roughness (Rms), and Maximum Roughness (Rmax), for areas of 625, 2500, 10829 and 67 646 μm2 were calculated. Results: Higher Ra, Rms and Rmax values were obtained for larger areas in all lenses. Daily disposable contact lenses (Nefilcon A and Ocufilcon B) presented the highest Ra, Rms and Rmax values, the larger changes in these parameters becoming apparent with the increase in the measured area. Differences between lenses were less obvious when data from 625 and 2500 μm2 area were compared. Conclusions: Daily disposable contact lenses showed the highest roughness surface. Analyzing larger areas might be adequate to detect differences between lenses in terms of surface characteristics, which may not be so obvious if smaller areas are studied. 相似文献