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31.
高效液相色谱法测定右旋儿茶素血浆浓度及药代动力学参数 总被引:1,自引:0,他引:1
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。 相似文献
32.
维胺酯-β-环糊精包合物的研究 总被引:6,自引:0,他引:6
应用3因素8水平的均匀设计方法,优化出维胺酯-β-环糊精包合物最佳制备条件,所得包合物的包合率为99.3%,其表观稳定常数为1394M-1. 相似文献
33.
带血管蒂岛状筋膜瓣移植治疗晚期类风湿性髋关节炎 总被引:1,自引:0,他引:1
目的:阐明带血管蒂岛状筋膜瓣移植治疗晚期类风湿性髋关节炎的疗效。材料和方法:对42例48髋晚期类风湿性髋关节炎病人采用以旋股外侧血管降支为蒂的股前外侧筋膜瓣移植行患髋成形术。结果:术后随访4~10.5年,平均4.5年,髋关节活动范围术前平均16.5°,术后228.6°,按照Charnley和吴之康人工髋关节置换术后的疗效评定标准,优良29髋、很好13髋、好6髋,尚可、差、很差无。结论:患者年龄在15~40岁之间为合适的治疗年龄。与人工髋关节置换术相比,本方法对髋关节正常结构破坏小;一旦手术失败仍可选用其它治疗方法弥补;且并发症少、费用低、远期效果好。 相似文献
34.
Interdigestive small bowel motility and duodenal bacterial overgrowth in experimental acute pancreatitis 总被引:10,自引:0,他引:10
I. D. Van felius L. M. A. akkermans K. bosscha A. Verheem W. Harmsen† M. R. Visser† & H. G. Gooszen 《Neurogastroenterology and motility》2003,15(3):267-276
The objective of this study is to investigate the effects of an acute necrotizing pancreatitis (ANP), without biliary obstruction, on the migrating motor complex (MMC), small bowel bacterial overgrowth (SBBO), bacterial translocation (BT) and infection of the pancreas simultaneously. Rats were divided into four groups: mild pancreatitis, control, ANP and sham operated control. Jejunal myoelectrodes were used to measure MMCs. Blood, peritoneal fluid, bile, and abdominal organs were harvested for microbial culturing 72 h after induction of pancreatitis. The splenic portion of the pancreas was taken for histology. During ANP the MMC cycle length was significantly increased from 14.1 +/- 0.2 to 22.4 +/- 1.9 min (P < 0.05). The duodenum of ANP rats was in contrast with the other groups characterized by Enterobacteriacae (> 3 log 10 CFU g-1 in seven of 12 rats, P < 0.05). A positive correlation (r = 0.78, P < 0.01) existed between duodenal Gram-negative and anaerobic flora and the MMC cycle. Correlation between MMC cycle length and BT to the pancreas was positive as well (r = 0.70, P < 0.01). A positive correlation (r = 0.85, P < 0.01) was found between the severity of pancreatitis and duodenal bacterial overgrowth. During ANP without biliary obstruction, the jejunal MMC is disturbed and consequently SBBO occurs. The correlation between the severity of pancreatitis, the disturbance of the MMC and SBBO suggests an important pathophysiological role of the proximal small bowel in the infection of pancreatic necrosis. 相似文献
35.
Akio Tanaka Motoyoshi Okamoto Dai Yoshizawa Shigeru Ito Patricia González Alva Fumio Ide Kaoru Kusama 《Journal of oral pathology & medicine》2007,36(7):400-404
BACKGROUND: Although it has been reported that ghost cells are present in odontomas, the generation mechanism of these cells is unclear. To evaluate the presence of ghost cells and involvement of the Wnt signaling pathway, we examined the expression of hard keratins, beta-catenin and Lef-1 in odontomas. METHODS: Sixty-nine cases of odontoma were examined immunohistochemically with the use of antibodies against human hair proteins, beta-catenin and Lef-1. RESULTS: Expression of hard keratins was found only in the cytoplasm of ghost cells in 46 (66.7%) of the 69 odontomas. Compound odontomas (78.8%) showed a higher incidence of ghost cells than complex odontomas (29.4%). Histopathologically, ghost cells were found within odontogenic epithelium adjacent to immature enamel and in the centre of Liesegang-ring-like calcified materials. Expression of beta-catenin and Lef-1 was observed in the cytoplasm and nucleus of odontogenic epithelial cells adjacent to the ghost cells in immature odontomas. CONCLUSION: These findings suggest that odontoma is a hard keratin-expressing tumor-like lesion, and that the Wnt signaling pathway may be involved in the formation of ghost cells in odontomas. 相似文献
36.
Twenty-six bone marrow transplant recipients, 14 of whom had evidence of acute graft versus host disease at autopsy, were studied. The pancreas in four of these patients exhibited changes thought to be due to acute graft versus host disease. Pathognomonic findings were in exocrine ducts which showed marked epithelial cellular atypia associated with a mild lymphocytic infiltrate. This was accompanied by ulceration and intraluminal haemorrhage in severe cases. In three of these four cases ductal epithelium showed marked hyperexpression of class I and class II major histocompatibility complex molecules. By contrast islets were not inflamed, showed no evidence of endocrine cell damage and no abnormalities of major histocompatibility complex expression were seen. 相似文献
37.
Localization of bone marrow-originated cells in the central nervous system (CNS) of the rat was investigated by using bone marrow chimeras. In order to do this, Lewis rats which carry major histocompatibility complex (MHC) class I antigens haplotype 1 (RT1.Al) were reconstituted with (Lew X PVG)F1 (RT1.Al/c) bone marrow cells after lethal irradiation. Transferred bone marrow cells were detected by immunohistochemical staining using a monoclonal antibody, OX27, specific for haplotype c of rat MHC class I antigens (RT1.Ac). The spleen and thymus of chimeric rats were fully reconstituted with transferred F1 cells 4 weeks after bone marrow transplantation. At this stage, mononuclear cells in the subarachnoid space of the CNS expressed OX27 antigen indicating that they were of bone marrow origin. A few OX27-positive blood cells were scattered in the CNS parenchyma 4-12 weeks after reconstitution. Ramified microglia, however, remained OX27-negative. Bone marrow-derived microglia were not observed throughout the period of examination until 24 weeks. In addition, experimental allergic encephalomyelitis (EAE) was induced in chimeric rats in order to augment the expression of MHC class I antigens on microglia. Even under this condition, no OX27-positive microglia were observed. Taken together, ramified microglia might be of neuroectodermal origin and there is little possibility that the microglia are derived from the bone marrow. However, if the ramified microglia are derived from blood cells, the microglia may be expected to have characteristic cell kinetics from the following points: (1) the precursor cells of the microglia may enter the CNS only at the perinatal stage; and (2) even under the condition in which lymphocytes and macrophages enter the CNS as observed in EAE, the precursor cells of the microglia are not supplied from the blood. 相似文献
38.
K. Karljikovi-Raji B. Stankovi A. Granov 《Journal of pharmaceutical and biomedical analysis》1990,8(8-12):735-738
The colour reaction of 4-hydroxyiminomethyl-1-methylpyridinium chloride (PAM-4Cl) and palladium(II) chloride has been investigated. The optimum reaction conditions, spectral characteristics, conditional stability constant and composition of the yellow water-soluble complex have been established. A new spectrophotometric method is proposed for the microdetermination of PAM-4Cl. 相似文献
39.
Hip arthroplasty is a common orthopaedic procedure with proven long-term success and reliable results. A wide range of associated conditions may affect the outcome of the arthroplasty and the surgeon has to keep these in mind when planning the surgery. In this article, such situations are discussed and recommendations are drawn from the evidence available in literature. 相似文献
40.
Abstract Closed suction drainage systems are commonly used in orthopaedic surgery, particularly in joint arthroplasty. The rationale
for the use of drains is a theoretical reduction of wound haematomas and infection. However the benefit of using drains after
total hip or knee arthroplasty is controversial. Several reports have shown that the use of drains does not reduce infection
and morbidity and is an unnecessary and potentially dangerous practice. In fact most studies highlighted that at best their
use appears to make no difference to important clinical outcomes. Recently a metaanalysis raised the question about the usefulness
of closed suction drainage again, concluding that it has no major benefits. The purpose of this study was to review the evidences
available concerning the utility of closed suction drainage outlining that this practice is not supported by clinical evidence. 相似文献