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161.
分别用聚二醇,1-2丙醇,无水乙醇与水组成不同比例的二元溶剂系统,测定了弱极性药物SMZ及TMP在上述各系统中的溶解度。从而导出药物溶解度与二混合溶剂体积分类间的半实验方程。 相似文献
162.
p53 mutation and protein accumulation during multistage human esophageal carcinogenesis. 总被引:22,自引:0,他引:22
W P Bennett M C Hollstein R A Metcalf J A Welsh A He S M Zhu I Kusters J H Resau B F Trump D P Lane 《Cancer research》1992,52(21):6092-6097
Preinvasive lesions of squamous cell carcinoma are well defined morphologically and provide a model for multistage carcinogenesis. Since alterations in the p53 tumor suppressor gene occur frequently in invasive esophageal squamous cell carcinoma, we examined a set of preinvasive lesions to investigate the timing of p53 mutation. Surgically resected tissues from nine patients with esophageal squamous cell carcinoma contained precursor lesions which had not yet invaded normal tissues. Immunohistochemistry showed high levels of p53 protein in both preinvasive lesions and invasive carcinomas in six cases; sequence analysis of all invasive tumors identified p53 missense mutations in two cases. Preinvasive lesions from both tumors with mutations plus one wild-type tumor were microdissected and sequenced. In one patient there were different mutations in the invasive carcinoma (codon 282, CGGarg > TGGtrp) and a preinvasive lesion (codon 272, GTGval > T/GTGleu/val). In a second case, an invasive carcinoma had a mutation in codon 175 (CGCarg > CAChis), and adjacent preinvasive lesions contained a wild-type sequence. A carcinoma and preinvasive lesion from the third case contained high levels of protein and a wild-type DNA sequence. Therefore, p53 mutation may precede invasion in esophageal carcinogenesis, and multifocal esophageal neoplasms may arise from independent clones of transformed cells. The timing of p53 protein accumulation is favorable for an intermediate biomarker in multistage esophageal carcinogenesis. 相似文献
163.
164.
脑水肿对大鼠血脑屏障内皮细胞膜表面ICAM—1表达量的影响 总被引:2,自引:0,他引:2
采用液氮冷冻Wistar大鼠-侧大脑制成血管源性脑水肿模型,将大怀脑冷冻中心制成冠状面冰冻切片,运用免疫组化染色观察脑水肿组及对照组白质脑屏障内皮细胞表面ICAM-1蛋白表达量的变化 。 相似文献
165.
Six patients, 4 of whom had complete atrioventricular (AV) canal and tetralogy of Fallot (TOF) and 2 of whom had double-outlet right ventricle with subaortic ventricular septal defect (VSD) and right ventricular outflow tract obstruction, were treated. Two of the patients with complete AV canal and TOF had a shunt procedure only. The other 4 patients underwent complete repair. All 6 patients survived the operation. Complete repair was performed through the right atrium using the two-patch technique. The size and shape of the VSD patch is important. Residual VSD after repair was common. Two patients have undergone successful reoperation for this problem. Another patient has a small residual VSD. 相似文献
166.
对11个人心标本沿右心室流入道和流出道各壁长轴纵行切开,再将各壁横切为上、中、下3份,各份按1mm厚度逐层切开,观察其各层肌纤维方向的角度并绘成坐标图。结果表明,右心室流入、流出道游离壁的肌纤维方向由浅入深基本上是渐变的。流入道游离壁的下1/3和流出道的上1/3,浅中层与内层之间可有纤维方向的突变。流入道隔壁的纤维方向从右向左逐渐移行,偶在左、右室内膜面有方向的改变。流出道右室面的中上部有一纤维方向变动较大的层次。对右心室各壁肌纤维方向的排列特或、分层、功能及其临床意义进行了探讨。 相似文献
167.
本实验采用血管铸型扫描电镜,注射明胶卡红组织切片显微镜下观察和注射铅丹乳胶追踪血管来源三种方法对14只健康大白鼠肾上腺血管构筑进行了研究。大白鼠肾上腺动脉发自腹主动脉和肾动脉。它们在行程中发出分支至腺体表面,再次分支穿入囊内,逐级分支至毛细血管。皮质动脉发自囊内血管,它们在皮质中分支分布。球状带的毛细血管与囊的毛细血管相连,毛细血管在球状带围绕细胞团形成网眼状;在束状带呈放射状排列;在网状带吻合增多形成网状。髓质动脉亦发自囊的血管,它们在皮质中不发分支直抵髓质,在髓质分成毛细血管。网状带的毛细血管越向髓质口径越粗,它们在皮髓交界处互相吻合形成更粗的静脉,这些静脉逐级吻合,最后形成一主干——中央静脉,它穿出皮质出现于肾上腺门处。左侧的中央静脉注入在肾静脉,右侧的注入下腔静脉。 相似文献
168.
中药肉苁蓉及其同属生药对免疫功能及酯质过氧化的作用 总被引:2,自引:0,他引:2
肉苁蓉为我国著名补益中药。以不同种的肉苁蓉的乙酸乙酯提取物和水提取物进行免疫药理试验,以不同种的水提物进行对脂质过氧化影响的试验。结果表明不同种肉苁蓉的提取物有强度不同的增强免疫功能和抑制脂质过氧化作用。 相似文献
169.
通过对97例截瘫住院患者连续10年的Hb测定结果进行回顾性分组研究,结果表明,无并发症组10年中Hb分布较一致,其均值与正常人比较无显著性差异(P>0.05),但12.3%的病例Hb水平低于正常人下限;当截瘫并发泌尿系感染、尿毒症或难治性褥疮等病症时,则导致Hb水平的降低。提出Hb测定结果,可做为在整体水平上观察截瘫患者的治疗及康复效果的指标。 相似文献
170.
Brigitte Schiller Chun He David J. Salant Alice Lim Jessy J. Alexander Richard J. Quigg 《The Journal of experimental medicine》1998,188(7):1353-1358
Crry (complement receptor 1–related protein/gene y) is a key cellular complement regulator in rodents. It is also present in Fx1A, the renal tubular preparation used to immunize rats to induce active Heymann nephritis (HN), a model of membranous nephropathy. We hypothesized that rats immunized with anti-Fx1A develop autoantibodies (auto-Abs) to Crry as well as to the megalin-containing HN antigenic complex, and that anti-Crry Abs promote the development of injury in HN by neutralizing the complement regulatory activity of Crry. Rats immunized with Fx1A lacking Crry remained free of proteinuria and glomerular deposits of C3 during a 10-wk follow-up despite typical granular immunoglobulin (Ig)G deposits in glomeruli. Anti-Fx1A auto-Abs were present in their sera at levels that were not different from sera pooled from proteinuric rats with HN induced with nephritogenic Fx1A. Passive administration of sheep anti-Crry Abs to rats immunized with Crry-deficient Fx1A led to proteinuria and glomerular C3 deposition, which were not seen in such rats injected with preimmune IgG, nor in rats with collagen-induced arthritis injected with anti-Crry IgG. To directly examine the role of Crry in HN, rats were immunized with Crry-deficient Fx1A reconstituted with rCrry. This led to typical HN, with 8 out of 15 rats developing proteinuria within 14 wk. Moreover, the extent of glomerular C3 deposition correlated with proteinuria, and anti-Crry Abs were present in glomerular eluates. Thus, Crry is a key nephritogenic immunogen in Fx1A. Formation of neutralizing auto-Abs to Crry impairs its function, leading to unrestricted complement activation by Abs reactive with the HN antigenic complex on the epithelial cell surface. 相似文献