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排序方式: 共有575条查询结果,搜索用时 15 毫秒
1.
JM Piepmeier DL Keefe MA Weinstein D Yoshida J Zielinski TT Lin Z Chen F Naftolin 《Canadian Metallurgical Quarterly》1993,32(3):422-30; discussion 430-1
Estramustine is an estradiol-based agent that has been shown to accumulate in human glioma cells, resulting in a concentration-dependent alteration in cell size and shape within minutes and an inhibition of proliferation over 3 to 6 days. We evaluated human glioblastoma cultures with [3H]thymidine incorporation assays to determine estramustine's early effects on deoxyribonucleic acid synthesis in these tumors. Because estramustine shares a common structural motif with other antimicrotubule drugs, we synthesized four A-ring conjugates of estrone that contained a carbamate moiety but lacked nitrogen mustard. These analogs were examined by [3H]thymidine incorporation and compared with vinblastine. Greater than 70% inhibition of [3H]thymidine incorporation occurred within 1 hour of treatment with estramustine at 10(-5) mol/L, which increased to 80% inhibition at 4 hours. Ethyl carbamate JE208 was nearly as effective as estramustine in inhibiting deoxyribonucleic acid synthesis, and both were more effective than vinblastine. The inhibitory effects of estramustine and estrone analogs were reversible; vinblastine was not reversible. Although estramustine and JE208 induced similar antiproliferative and morphological changes in glioblastoma cells that persisted for at least 4 days, there was a modest recovery of morphology and thymidine incorporation with JE208 after prolonged treatment. The common findings with estramustine and JE208 suggest that these agents may have a similar mechanism of action and form the basis for the investigation of new agents that may rapidly and reversibly inhibit glioblastoma. 相似文献
2.
TT Wu SH Swerdlow J Locker D Bahler P Randhawa EJ Yunis PS Dickman MA Nalesnik 《Canadian Metallurgical Quarterly》1996,27(2):157-164
This paper discusses the problem of violence and its expression upon mortality due to external causes. A few indicators are offered, which have been worked upon it to emphasise the importance of the theme. In a general way, the study demonstrates violent death has had its magnitude increased along the years, not only throughout Latin America but also in Brazil and in Santa Catarina. 相似文献
3.
NI Koval'chuk FN Shubin VA Khoroshko FN Sheverdina TT Tarasenko NG Kosheleva 《Canadian Metallurgical Quarterly》1997,(5):88-91
The results of the comparative study of the phenotypical properties and the plasmid profile of 63 strains of salmonellae, belonging to 44 serotypes of groups B, C1, C2, C3, D, E1, E4, F. The study revealed that strains of different serotypes had their individual plasmid profile. Strains of the same serotype of salmonellae isolated from similar sources had an identical plasmid profile, while strains isolated from different sources differed in their plasmid profiles, though they might have a similar phenotype. Plasmid analysis was shown to be an effective method for the intraspecific typing of rarely isolated Salmonella serotypes and suitable for use as the basis of the microbiological monitoring of salmonellae. 相似文献
4.
This is a study of the differences in the risk factors for being either hepatitis B surface antigen positive [HBsAg(+)] or antibody to hepatitis C virus positive [Anti-HCV(+)] in A-Lein, a rural area in southern Taiwan, an area which also has a high hepatoma mortality rate. Three hundred eighty-five patients age > or =40 years participated in hepatoma screening at the A-Lein Community Health Center during 1995. Those who were HBsAg(-) and anti-HCV(-) or had coinfection of HBsAg(+) and anti-HCV(+) were excluded, leaving 293 patients: 109 HBsAg(+) and 184 anti-HCV(+). The anti-HCV(+) patients had a lower socioeconomic status (as defined by level of education and type of occupation) and were older than HBsAg(+) patients (P < 0.05). Those with higher alanine aminotransferase levels (ALT) also had a higher anti-HCV(+) to HBsAg(+) odds ratio (OR), and a dose response relationship was found, P < 0.0001. Anti-HCV(+) patients were more likely than HBsAg(+) patients to have a spouse who shared the infection, OR = 5.11; 95% CI, 2.30-11.28. Anti-HCV(+) patients were more likely than HBsAg(+) patients to have had blood transfusions (OR = 2.66; 95% CI, 1.20-5.89), frequent medical injections (OR = 2.64; 95% CI, 1.62-4.31), or injections by non-licensed medical providers (OR = 1.91; 95% CI, 1.18-3.09). Multiple logistic regression analysis showed that the significant factors for anti-HCV(+) patients vs. HBsAg(+) patients are drinking habit (OR = 3.45; 95% CI, 1.02-11.60), age (OR = 6.33; 95% CI, 2.93-13.68), and frequent medical injections (OR = 2.88; 95% CI, 1.65-5.03). The transmission of hepatitis C in A-Lein is closely related to low socioeconomic status, age, alcohol abuse, spouses being anti-HCV(+), and frequent medical injections, especially from non-licensed medical providers, including both pharmacists and those with no medical licensing whatsoever. These nonlicensed medical providers sometimes reuse needles to save money, which is a likely route of infection. 相似文献
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RH Rau YL Chan HI Chuang CR Cheng KL Wong KH Wu TT Wei 《Canadian Metallurgical Quarterly》1997,35(2):113-118
While current psychiatric taxonomies recognise a classification of amphetamine dependence, derived from the notion of an alcohol dependence syndrome, little research has validated that such a condition exists for this drug. Current amphetamine users (N = 331), were interviewed using the World Health Organization operationalisation of DSM-III-R substance dependence criteria, and a measure of the psychological components of dependence. Structural analyses indicated that a unidimensional dependence syndrome as assessed by DSM-III-R and DSM-IV criteria exists for amphetamine, and that physiological, psychological and behavioural indicators were all important in accounting for the variance in responses. It was demonstrated that the concept of a dependence syndrome is applicable to amphetamine, and that the inclusion of the amphetamine dependence syndrome in DSM-III-R and DSM-IV is valid. 相似文献