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排序方式: 共有358条查询结果,搜索用时 421 毫秒
71.
Obstruction of the small intestine: accuracy and role of CT in diagnosis 总被引:17,自引:0,他引:17
Maglinte DD; Gage SN; Harmon BH; Kelvin FM; Hage JP; Chua GT; Ng AC; Graffis RF; Chernish SM 《Radiology》1993,188(1):61
72.
我们成功地建立了一个新的层析等电点聚焦的三步程序.细菌培养液首先以CG-50吸附,洗脱出的粗毒素溶液在PBE_(94)柱上进行层析等电点聚焦.分别用5mMTris-Base pH9.4和Buffalyte_(8-4) pH5.4缓冲液洗脱,出现多个洗脱峰,即刻测定pH值.收集pH6.8~7.1的洗脱液,混合、浓缩,最后通过Sephacryl s-200过滤,以0.05M PBS pH6.8洗脱,出现3个峰,毒素在第1峰.毒素纯度为98%,回收率89%,p17.6,MW28500,SDS-PAGE上1条带.以~(125)I标记SED作探针的电泳转移和放射自显影均证明了提纯SED的免疫学特异性.免疫扩散试验,即使200μg/ml SED与不产毒素的FRI-184抗血清,也未有可见沉淀线. 相似文献
73.
We investigated whether cigarette smoking, measured by follicular fluid
concentrations of cotinine (a major metabolite of nicotine), affects the
maturity of oocytes from women undergoing in-vitro fertilization (IVF) and
embryo transfer. In 234 women, follicular fluid samples were assessed for
cotinine and their 2020 oocytes were assessed for maturity stage. Data on
individual proportions of oocytes which were mature (OM) and were
fertilized (OF) were analysed by regression in relation to age and
follicular fluid cotinine. OF gave an independent assessment of oocyte
maturity. Both age and follicular fluid cotinine entered the OM and OF
regressions and were significant. The age-adjusted regression coefficients
for log cotinine were positive; greater cotinine concentrations usually
accompanied greater OM and OF. The cotinine effect on OM was positive in
younger women, but it became negative (decreased OM with increasing
cotinine concentrations) in older women (> or = 40 years). We further
found in older women an average reduction of approximately 50% in the
number of mature oocytes; this reduced number was lower than the number of
embryos usually transferred. Smoking can reduce the number of mature
oocytes even further, therefore risking a negative IVF-embryo transfer
outcome. This may be the reason why the negative effects of smoking become
clinically detectable in older women.
相似文献
74.
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76.
Papillary endolymphatic sac tumors: CT, MR imaging, and angiographic findings in 20 patients 总被引:6,自引:0,他引:6
77.
To quantitatively map and compare patterns of regional cardiac metabolism with greater spatial resolution than is possible with positron emission tomography (PET), the authors developed autoradiographic techniques for use with combinations of radiolabeled fluorodeoxyglucose (FDG), glucose (GLU), and acetate (ACE) and applied the techniques to normal rats. Kinetic models were developed to compare GLU-based oxidative glucose metabolism with FDG-based total glucose metabolism (oxidative plus anaerobic) and to compare ACE-based overall oxidative metabolism with FDG-based total glucose metabolism. GLU-based metabolism generally paralleled FDG-based metabolism, but divergence occurred in certain structures such as the papillary muscles, where FDG-based metabolism was much greater. ACE-based metabolism also generally paralleled FDG-based metabolism, but again, the papillary muscles had relatively greater FDG-based metabolism. These discrepancies between FDG-based metabolism and GLU- or ACE-based metabolism suggest the presence of high levels of anaerobic glycolysis. Thus, the study indicates that anaerobic glycolysis, in addition to occurring in ischemic or "stunned" myocardium (as has been shown in recent PET studies), occurs normally in specific cardiac regions, despite the presence of abundant oxygen. 相似文献
78.
维拉帕米对大鼠肝脏贮脂细胞增殖及胶原基因表达的影响 总被引:2,自引:0,他引:2
在肝纤维化的发生发展过程中,细胞外基质的过度合成和异常沉积是最主要的病理过程。研究表明,病理状态下,贮脂细胞(FSC)被激活,数量增多,分泌大量的胶原等细胞外基质,导致肝纤维化的发生、发展[1]。材料和方法一、实验动物雄性SD大鼠10只,其中5只皮下注射40%CCl4茶油溶液建立肝纤维化模型。二、试剂链霉蛋白酶和Nycodenz购于Sigma公司;胶原酶购于上海医工院;维拉帕米(Ver)购于Knoll公司;RNA提取剂、P32dCTP、随机引物标记试剂盒购于Gibco、亚辉、Promega公司三… 相似文献
79.
新生牛跟腱胶原蛋白海绵与细胞的生物相容性 总被引:1,自引:1,他引:1
目的:采用新生牛跟腱制备生物医用胶原蛋白海绵,通过分别接种Vero细胞、天祝白牦牛胚胎皮肤原代细胞和岷县黑紫羔羊睾丸原代细胞至胶原蛋白海绵组织支架上,观察新生牛跟腱胶原蛋白海绵与3种细胞的生物相容性。方法:实验于2006-02/05在西北民族大学生命科学与工程学院生物工程与技术国家民委重点实验室完成。①用新生牛跟腱经冰醋酸、胃蛋白酶等消化,经盐析、透析及冻干等处理后,制备成胶原蛋白海绵。②在六孔板中,将Vero细胞、天祝白牦牛胚胎皮肤原代细胞和岷县黑紫羔羊睾丸原代细胞分别接种于经紫外线、臭氧灭菌后的胶原蛋白海绵上,经37℃体积分数为0.05的CO2恒温培养;并用另一组细胞在凯氏瓶中培养作对照实验。用奥林帕斯倒置相差显微镜及JVC摄像系统观察、拍摄与记录细胞生长情况,并于培养11d,用考马斯亮蓝和苏木精-伊红染色,证实相差显微镜观察的结果。结果:①胶原蛋白海绵制备结果:用新生牛跟腱制备得到具有一定孔隙度的胶原蛋白海绵,经紫外线、臭氧灭菌后可进行细胞培养。②3种细胞在胶原蛋白海绵上和六孔板底的生长情况:3种细胞接种后5h,在胶原蛋白海绵周围的六孔板孔底可看到Vero细胞已贴壁、伸展,个别细胞有分裂现象,在胶原蛋白海绵表面,隐约可见圆形细胞排列。Vero细胞和天祝白牦牛胚胎皮肤原代f2细胞接种72h、岷县黑裘皮羔羊睾丸原代f2细胞接种48h时,孔底细胞已经铺满单层,但与对照孔比较,生长速度较慢。②3种细胞用考马斯亮蓝细胞骨架染色和苏木精-伊红染色的结果:培养到第11天,3种来自不同动物、不同组织的细胞接种的胶原蛋白海绵支架孔中均有大量细胞良好生长,胶原海绵外观变得挺拔、透明、有韧性。结论:新生牛跟腱胶原蛋白海绵,对Vero细胞、天祝白牦牛胚胎皮肤原代细胞和岷县黑紫羔羊睾丸原代细胞无毒性,3种细胞均能在其上良好生长,但在体内是否会引起免疫排斥反应,还有待进一步研究。新生牛跟腱有望成为医用胶原蛋白海绵产品新的原材料。 相似文献
80.
Association between gelatinase release and increased plasma membrane expression of the Mo1 glycoprotein 总被引:7,自引:0,他引:7
Mo1, a glycoprotein heterodimer (gp 155,95) that functions as an adhesion promoting molecule and as the C3bi receptor of human myeloid cells, is expressed in increased amounts in the plasma membrane after exposure of polymorphonuclear leukocytes (PMNs) to various stimuli. Previous studies have suggested that secondary granules represent an intracellular pool of Mo1 that, upon degranulation, fuse with the plasma membrane resulting in a tenfold increase in surface expression of Mo1. To determine the intracellular location of Mo1, we monitored Mo1 expression by immunofluorescence and compared it to the release of myeloperoxidase (MPO, a marker for the primary granules), vitamin B12 binding protein (B12BP, secondary granules), and gelatinase (gelatinase- containing organelles) following exposure to various stimuli. Human neutrophils stimulated with 20 mmol/L fluoride for 16 minutes exhibited a twofold increase in Mo1 expression and gelatinase release but no enhanced release of primary or secondary granular contents. In a similar fashion, incubation of cells at 37 degrees C for five minutes with 7.5 X 10(-9) to 10(-6) mol/L N-formyl-methionyl-leucyl- phenylalanine (FMLP) resulted in significant increases in both surface Mo1 expression (three- to fivefold) and gelatinase release (five- to eightfold) without significant release of either MPO or B12BP. In addition, both the fluoride and FMLP experiments demonstrated that Mo1 up-modulation alone is not sufficient to activate superoxide (O2-) production. These data indicate that at least one intracellular storage pool of Mo1 is the gelatinase-containing organelles and that their fusion with the plasma membrane results in increased expression of Mo1 on the cell surface. 相似文献