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Effects of cefminox (CMNX) on hemostasis and blood coagulation system were studied. Adult in-patients admitted to 237 centers (310 clinics) nationwide in Japan during the period from April 1988 to March 1989 were followed up using a newly designed uniformed protocol. Case cards recovered were inspected by an evaluation committee and patients to be included in analysis were determined according to the protocol. Presence or absence of abnormalities in the hemostasis and blood coagulation system was examined objectively using criteria for evaluation prepared by the committee. Out of 1,374 patients included in analysis, 10 patients were judged as having abnormalities which were suspected to have causal relationships with CMNX. Prolongation in prothrombin time was observed in 4 cases (0.29%), prolongation in activated partial thromboplastin time in 4 cases (0.29%), and decrease in fibrinogen in 2 cases (0.15%). Decrease in platelet count was not detected in any of the cases. Cross-sectional analysis according to background factors in these 10 cases revealed that abnormalities of the hemostasis and blood coagulation systems were significantly higher (P less than 0.01) for the group positive for underlying disease or complications ("positive" group) than the "negative" group. Five out of 9 patients of the positive group had malignant neoplasm. Other than this factor, no items showed statistically significant differences. From these results it is considered that the administration of CMNX is nearly free of effects on the hemostasis and blood coagulation system and development of laboratory abnormalities is chiefly due to the patients' condition.  相似文献   
105.
通过检测E6变体在HPV16阳性的宫颈非典型增生(CIN)和宫颈浸润癌(ICC)患者中的分布,研究其致癌能力.方法:用PCR和双脱氧终止荧光法检测了42例E6基因点突变及其编码氨基酸改变,统计分布差异.结果:2例(5%)为原型,40例(95% )的E6DNA序列中含有1至3个点突变,导致13类E6氨基酸残基改变,组合成17种(94%)HPV16变体.出现频率较高的4种变体在CIN和ICC病例中共同存在,分布无显著性差异(P>0.05).DNA的点突变数在CIN和ICC病例中的分布也无显著性差异(P>0.05).结论:HPV16E6的变体多于原型,但是变体和原型的致癌能力没有明显差别.  相似文献   
106.
A long-standing assumption in molecular biology posits that the conservation of protein and nucleic acid sequences emphasizes the functional significance of biomolecules. These conserved sequences fold into distinct secondary and tertiary structures, enable highly specific molecular interactions, and regulate complex yet organized molecular processes within living cells. However, recent evidence suggests that biomolecules can also function through primary sequence regions that lack conservation across species or gene families. These regions typically do not form rigid structures, and their inherent flexibility is critical for their functional roles. This review examines the emerging roles and molecular mechanisms of “nondomain biomolecules,” whose functions are not easily predicted due to the absence of conserved functional domains. We propose the hypothesis that both domain- and nondomain-type molecules work together to enable flexible and efficient molecular processes within the highly crowded intracellular environment.  相似文献   
107.
We evaluated retrospectively the pharmacokinetics and boron uptakeof BSH (mercaptoundecahydrododecarborate) for Boron Neutron Capture Therapy(BNCT) in 123 patients undergoing craniotomy for intracranialtumors. The pharmacokinetics revealed that BSH could moveeasily from blood to the peripheral organs; itwas retained there and elimination was very slow.BSH after intra-arterial infusion (IA) was found tomove into the peripheral organs more easily thanafter intra-venous (IV) infusion.In patients with malignant glioma, the average valuesof boron concentration in tumor and the tumorto blood ratio (T/B ratio) after IA infusionwere 26.8 ± 19.5 g/g (range, 6.1–104.7 g/g)and 1.77 ± 1.30 (range, 0.47–6.65) respectively. Onthe other hand, after IV infusion the valueswere 20.9 ± 12.2 g/g (range, 7.0–39.7 g/g)and 1.30 ± 0.65 (range, 0.61–2.94) respectively. Thedifferences are not statistically significant. Boron uptake inmalignant glioma was about three times higher thanlow grade glioma. We found a good correlationbetween boron uptake and time interval from BSHinfusion, and 15–20 hours after BSH infusion theboron concentration in tumor was above 20 g/g10B in 69% of the malignant glioma patients;T/B ratio was above one in 75%, andabove two in 44% of them.We recommend intra-venous infusion of BSH clinically sinceit is safer, and results in sufficient boronconcentration in tumor, and the planned irradiation mightbe optimal around 15–20 hours after the BSHinfusion for treating malignant glioma.  相似文献   
108.
The cytotoxic effects of 2,6-di-tert-butyl-4-methylphenyl N-methylcarbamate (terbutol) and its major metabolites were investigated in freshly isolated rat hepatocytes. Terbutol and its metabolite, especially 2,6-di-tert-butyl-4-methylphenyl carbamate (N-demethylterbutol), at a concentration of 1.0 mM resulted in a time dependent cell killing accompanied by losses of intracellular ATP, protein thiols, and glutathione (GSH) and the accumulation of oxidized GSH. Supplementation of the hepatocyte suspension with 5 mM N-acetylcysteine, a precursor of intracellular GSH, inhibited the cytotoxicity of N-demethylterbutol. In mitochondria isolated from rat liver, terbutol and its metabolites impaired respiration related to oxidative phosphorylation and the potency of their toxicity is associated with impairment of mitochondrial respiration. These results indicate that N-demethylterbutol is the most cytotoxic followed by terbutol and other metabolites, and that both the mitochondrial respiratory system and protein thiols are important targets for these compounds.  相似文献   
109.
To investigate the role of p53 abnormalities in predicting the survival of patients with non-small cell lung cancer (NSCLC), polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and immunohistochemical analyses were performed on 74 and 67 tumor samples, respectively, from patients with pathological stage I-IIIa NSCLC. An abnormally migrating SSCP band was observed in 21 of 74 (28%) tumor specimens. DNA sequence analysis revealed 23 intragenic mutations including 3 small deletions and 20 point mutations. Immunohistochemical analysis using the DO-7 monoclonal antibody showed abnormal expression of p53 in 27 of 67 (40%) patients. The concordance rate between immunohistochemical and PCRSSCP analyses was 73% (49/67) in this study. Univariate and multivariate analyses demonstrated that abnormal expression of p53 may be associated with prolonged survival (p=0.0997 and 0.0099, respectively). In contrast, no relationship was observed between p53 mutation and overall survival (0.6968). These results suggest that p53 status and the survival outcome changes between immunohistochemical and mutational analyses in stage I-IIIa NSCLC.  相似文献   
110.
A new hepatocellular diffusion model was developed to kinetically evaluate the hepatobiliary transport processes of drugs in the perfusion system, based on the physiological structure of the liver. Since the equations describing the hepatocellular diffusion phenomena were derived as image forms in the Laplace domain, the fast inverse Laplace transform (FILT) was adopted to manipulate the image equations. Cefixime and cefpiramide were selected as model drugs. The concentrations in the perfusate and the excreted amounts into the bile were simultaneously measured at appropriate intervals after the rapid administration of each drug into the portal vein. The hepatocellular diffusion model was fitted to the biliary excretion profiles from rat livers, by means of a nonlinear least squares program, MULTI(FILT). According to this model, the hepatobiliary transport process of drug is kinetically separated into three steps, that is, the diffusion into and through the hepatocytes, the transfer from the hepatocytes into the bile canaliculi, and the movement through the bile canaliculi to the outlet of bile duct. These steps are characterized by the diffusion rate constant through hepatocytes (kdif), the permeability rate constant into the bile canaliculi (kbmc) and the transit time through the bile canaliculi to the outlet of bile duct ( ), respectively. It was demonstrated that kdif of cefixime (0.023min1) was significantly smaller than that of cefpiramide (0.044 min1), while the differences in kbmc and were not obvious between cefixime and cefpiramide. kbmc and of both drugs were about 1.2 min1 and about 1.0 min, respectively. These parameters were correlated to the excretion ratio into the bile (Fbile) and the mean transit time from the sinusoid through the hepatocytes to the outlet of bile duct ( ).  相似文献   
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