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131.
To explain the mechanism of renal injury caused by liver ischemia-reperfusion, we investigated biochemical and morphological changes in the liver and kidney in rats. After reperfusion following 60 min of liver ischemia, numerous changes were found. The level of serum transaminases and lipid peroxide formation in the liver tissue increased significantly. Electron microscopic studies revealed that most of the hepatocytes had swollen mitochondria and clumping of the nuclear chromatin. The sinusoidal endothelium was disrupted and the sinusoidal lumen was filled with numerous erythrocytes. Blood endotoxin concentration, plasma lipid peroxide levels, and serum -glucuronidase activities were significantly higher than in the control group. Biochemical and morphological renal injury was also observed. Tissue lipid peroxide levels increased in both the kidney and the liver. Microscopic examination revealed damage to the renal tubules, including interstitial edema, dilatation of the lumen, and granular casts derived from necrotic cells in the proximal convoluted tubule. The levels of urinary N-acetyl--d-glucosaminidase (NAG) in the liver ischemia-reperfusion group were also higher than in the control group. These results suggest that the renal injury was caused by an increase in endotoxin, lipid peroxide, and lysosomal enzymes in the blood following the liver injury induced by the ischemia-reperfusion.  相似文献   
132.
The localization of Cu/Zn- and Mn-superoxide dismutase (SOD) in breast cancer tissue (12 papillotubular carcinomas, 21 solid-tubular carcinomas, 16 scirrhous carcinomas, 1 medullary carcinoma, 1 secreting carcinoma, 1 lobular carcinoma, 1 Paget's disease) was investigated via an immunohistochemical technique using antihuman Cu/Zn- and Mn-SOD antibodies in 10%formalin fixed-paraffin embedded thin sections. Both SODs stained strongly in the normal breast gland, but not clearly in many cancer tissues. Furthermore, Cu/Zn-SOD stained more strongly in well differentiated tubular carcinomas than in poorly differentiated tubular carcinomas. It tended to stain less in tumors which recurred or had a poor outcome, and in tumors with a diploid pattern on DNA flow cytometry. Mn-SOD staining was similar to that of Cu/Zn-SOD, but no significant differences among subgroups was found, since the incidence of positively staining tumors was too small in all groups. The intensity of SOD staining seems to change in relation to cell proliferation and differentiation in breast carcinoma, and may be a prognostic indicator, since SOD decreased in poorly differentiated carcinoma and in tumors which developed distant metastasis. Thus, the localization of SOD in breast cancer tissue can provide useful information for cancer treatment.  相似文献   
133.
To plan the optimal BNCT using BSH for glioblastoma patients, the10B concentration in tumor and blood was investigated in 11newly diagnosed glioblastoma patients. All patients received 20 mg BSH/kgbody weight 2.5–16 hrs prior to tumor removal. The quantitativedistribution of 10B was determined by prompt gamma rayspectrometry and/or -track autoradiography. 10Bdistribution in tumors was heterogeneous, ± 25% of scatteringat the microscopic level, and the distribution was also heterogeneous at thetissue level. 10B concentration in blood decreased inbi-exponential decay as a function of the time after the end of theadministration. The T/B ratio showed non-exponential increase with largevariation. The maximum T/B ratio would be around 1. The tumor/normal brain(T/N) ratio of 10B concentration was 11.0 ± 3.2. The10B content in normal brain is originated in vascular10B in parenchyma, since the 10B content innormal brain to blood (N/B ratio) being compatible with the blood content inparenchyma. These values allow for BNCT, using thermal neutrons, on braintumors located less than approximately 3.3 cm in depth from the brainsurface of neutron incidence, providing that the dose on the normalendothelium is controlled to less than the tolerance limit. In ourpreliminary study of BNCT, a 31% 3-year survival was achieved overall for 16 glioblastoma patients and a 50% 2-year survival wasachieved on 8 glioblastoma patients in our recent dose escalation studybased on these data.  相似文献   
134.
  1. P-glycoprotein, a 170–180 kDa membrane glycoprotein that mediates multidrug resistance, hydrolyses ATP to efflux a broad spectrum of hydrophobic agents. In this study, we analysed the effects of three MDR reversing agents, verapamil, cyclosporin A and [3′-keto-Bmt]-[Val*]-cyclosporin (PSC 833), on the adenosine triphosphatase (ATPase) activity of human P-glycoprotein.
  2. P-glycoprotein was immunoprecipitated with a monoclonal antibody (MRK-16) and the P-glycoprotein-MRK-16-Protein A-Sepharose complexes obtained were subjected to a coupled enzyme ATPase assay.
  3. While verapamil activated the ATPase, the cyclosporin derivatives inhibited both the substrate-stimulated and the basal P-glycoprotein ATPase. No significant difference was observed between PSC 833 and cyclosporin A on the inhibition of basal P-glycoprotein ATPase activity. PSC 833 was more potent than cyclosporin A for the substrate-stimulated activity.
  4. Kinetic analysis indicated a competitive inhibition of verapamil-stimulated ATPase by PSC 833.
  5. The binding of 8-azido-[α-32P]-ATP to P-glycoprotein was not altered by the cyclosporin derivatives, verapamil, vinblastine and doxorubicin, suggesting that the modulation by these agents of P-glycoprotein ATPase cannot be attributed to an effect on ATP binding to P-glycoprotein.
  6. The interaction of the cyclosporin derivatives with ATPase of P-glycoprotein might present an alternative and/or additional mechanism of action for the modulation of P-glycoprotein function.
  相似文献   
135.
The localization of apolipoprotein E (ApoE) has been examined immunohistochemically in the autopsied brains of middle-aged and old-aged control subjects, with and without amyloid protein (A) deposits, and of Alzheimer's disease patients. Senile plaques were consistently labeled with ApoE antiserum even in the very early stage of senile plaque formation seen in the fifth decade. In the cerebellar molecular layer, small dots of ApoE immunoreactivity, which were prominent in the Alzheimer's disease subjects, were observed in addition to immunoreactivity in diffuse plaques. ApoE antisera labeled all of the extracellular neurofibrillary tangles (NFT), whereas only a small minority of extracellular NFT were positive for A. A punctate pattern of ApoE immunoreactivity was seen at the media of the meningeal vessels lacking amyloid, when senile plaques were present in the nearby cortex. In the early stage of amyloid angiopathy, the distribution of ApoE immunoreactivity was much more extensive than that of A positivity. These findings suggest that ApoE accumulates in the early stage of senile plaque formation and, furthermore, that ApoE accumulation precedes A deposition in extracellular NFT and amyloid angiopathy.  相似文献   
136.
We examined different fluorescent probes suitable for fluorometric determination of 1-acid glycoprotein (AGP) in serum. Quinaldine red (QR) was shown to bind strongly and selectively to AGP. Taking advantage of the enhanced fluorescence of QR in the presence of AGP, we developed a direct method for the determination of serum AGP without removal of other serum proteins such as albumin. AGP concentrations in serum of healthy volunteers and patients correlated well with results from the conventional single radial immunodiffusion (SRID) method (r = 0.93, slope = 1). The newly developed method is faster and has a larger analytical concentration range than the SRID method. This method can also be used to determine AGP in serum of experimental animals, and it can serve to monitor AGP serum concentrations for pharmacokinetic evaluation of basic drugs.  相似文献   
137.
After the conclusion of the trial was carried out on december 25th in the 18th year of the Meiji era, write-ups decreased graduallly. Under these circumstances, the traders of medicine began their own publication at their convenience and they put advertisements in them. "Eisei-tebako" by "Kishida ginko" and "Houtan-keikenroku" by "Morita Jihei" were the typical of them. While patent medicines were extremely popular, pharmacists at that time never denied the necessity of patent medicines. Junichiro Shimoyama and Keizo Tanba, who were representatives of pharmacists in Japan, suggested that pharmacists had ought to manage patent medicines and pointed out that excessive write-ups exacerbated the situation.  相似文献   
138.
In February 1869, the government first permitted newspapers to be published. The Yokohama-mainichi, the Tokyo-nichi-nichi, the Nisshin-shinjishi and so on were published. The traders of medicine quickly turned their attention to the newspapers. Jihei Morita put an advertisement about "Houtan" in the newspaper issued in July in the 4th year of the Meiji era (1871) and Ginko Kishida put an advertisement about "Seikisui" in the Mainichi in Yokohama dated August 18th in the 4th year of the Meiji era. After that, the traders of medicine advertised in newspapers one after another, and the contents of advertisements were expressly the efficacy of medicine. As Yukichi Fukuzawa doubted if the trend was really desirable, he carried his comment against the trend in the Katei Sodan published by Keio-Gijuku, but the contents of advertisements were not changed. Advertisements emphasising the efficacy of medicine were prominent.  相似文献   
139.
The incidence and clinicopathologic features of unilateral multicentric breast cancer (UMBC) were studied by mammary gland serial sectioning in 116 cases of clinically defined monocentric breast cancer (MONBC) examined histopathologically at the Nagano Cancer Detection Center. UMBC was defined as: 1) histopathologically discontinuous tumors each with an intraductal spread, 2) at least one tumor-free section separating two tumors, and 3) a large primary tumor and other small secondary tumors. UMBC was detected in 23 of 116 cases (19.8%), all with one secondary tumor. Primary and secondary tumors were located in the same quadrant in 34.8% and in different ones in 65.2%. The secondary tumors were <5 mm in size in 56.5%. Secondary tumors, averaging 8.3 mm in size and 25.5 mm in distance from the primary tumor, were almost exclusively noninvasive carcinomas, including 15 (65.4%) noninvasive ductal carcinomas and several special types. The primary and secondary tumors were of the same histologic type in 3 of 23 cases. UMBC patients averaged 6 years younger than MONBC patients, and the incidence of UMBC tended to be higher in younger patients (p<0.1). UMBC tended to occur more frequently in quadrant with an average histologie tumor size significantly smaller than that in MONBC (p<0.01). The histologie types of the primary tumor in UMBC and MONBC were similar, with common types predominant. Lymph node metastases tended to be slightly more frequent in MONBC. This high incidence of UMBC calls for careful attention when considering breast conserving therapy.  相似文献   
140.
Hepatic vitronectin expression was assessed in 27 patients with chronic hepatitis C before and after interferon alpha treatment and in 7 control patients. Before interferon therapy, vitronectin was localized in the hepatocytes and in the portal and central venous regions. A high correlation was found for the vitronectin expression level with the histological grading and staging scores in the hepatocytes as well as in the portal region. After interferon therapy, the hepatic vitronectin was significantly decreased in the sustained and transient responders, but it was not as markedly decreased in the nonresponders and the non-treated group. A good correlation was found for the vitronectin expression with the staging scores but not with the grading scores in the portal region. These findings suggest that hepatic vitronectin is influenced by interferon therapy and that it may play an important role as a hepatic adhesion molecule through the improvement of inflammation, necrosis and fibrogenesis.  相似文献   
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