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61.
We have previously isolated a drug-resistant, [PC3(R)], variant of human prostate PC3 cell line, which showed significant resistance (>10-fold) to adriamycin. No known mechanisms of drug resistance were found; however, resistant cells expressed more bcl2, c-myc, and ms oncogenes compared to the sensitive cells. In this study, we found that buthionine sulfoximine (BSO), an inhibitor of gamma-glutamyl-cysteine synthetase, decreased glutathione levels by 80-90% in both cell lines. BSO treatment down-modulated Ras protein only in PC3(R) cells and caused a 4-fold sensitization of PC3(R) cells to adriamycin without affecting PC3(W) cells. Farnesol treatment also inhibited expression of Ras protein and concomitantly reversed adriamycin resistance in PC3(R) cells, indicating that altered levels of ras expression plays an important role in drug resistance in PC3(R) cells. 相似文献
62.
The Caribbean Food and Nutrition Institute conducted a survey of anemia status of pregnant and/or lactating women in Jamaica (1982), Montserrat (1981), and St. Vincent and the Grenadines (1985). After various interventions designed to reduce the prevalence of anemia in pregnant women, follow-up surveys were conducted in the same countries five years after the initial surveys to determine whether or not the prevalence of anemia in pregnant women did indeed fall after these interventions. As of July 1984, the Jamaica Flour Mills began fortifying all baking flour and counter flour with iron (44 mg/kg) (a 70% increase in the amount of iron added), thiamine (6.3 mg/kg), riboflavin (3.9 mg/kg), and niacin (52.8 mg/kg). During the five year period following the initial survey in Montserrat, health workers had changed the type of iron administered to pregnant women, a constant supply of iron tablets was established, and the economy had improved. The changes in St. Vincent and the Grenadines were that the government provided a constant supply of iron folate (ferrous folate) tablets and there was a 1988 workshop on a manual on the control of anemia where nurses were trained in better clinic management of anemia. The prevalence of anemia (Hb 11 g/dl) in pregnant women fell from 61.6% to 53% (p 0.09) in Jamaica. It fell from 82.3% to 22.1% in Montserrat (p 0.0001). The prevalence of anemia (Hb 10 g/dl) in pregnant women fell from 25% to 14.5% (p 0.001) in St. Vincent and the Grenadines. These findings show that different interventions may have contributed to the reduction in the prevalence of anemia in pregnant women in Jamaica, Montserrat, and St. Vincent and the Grenadines. 相似文献
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Shrivastava SK Sharma HP Sinha SK Prasad KM 《Indian journal of pathology & microbiology》1999,42(2):169-170
We report a rare case of Retroperitonial teratoma containing Axial Skeleton long bone. Jaw, pelvis & scapula in a 27 yrs old male. Aberration in monozygotic twinning may rarely present as Fetus in Fetu. Rarer is presentation in Adult. 相似文献
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Karmy-Jones R Vallieres E Culver B Raghu G Wood DE 《The Annals of thoracic surgery》1999,67(2):550-551
We describe a rare case of fatal air embolism in a patient in whom a left atrial-bronchial fistula developed 1 month after single lung transplant. The cause was a combination of mediastinal infection and bronchial necrosis. 相似文献
68.
This paper presents a review of the current status of empirical research in the area of alcohol craving. After an introduction on the origins of the construct of craving, we first present clinical studies that have examined craving as a hallmark symptom of alcohol dependence and demonstrated its sensitivity as an outcome measure in assessing change in pharmacotherapy trials of alcohol dependence. There is also discussion regarding new multifactorial self-report instruments of alcohol craving with good reliability and predictive validity, that may be sensitive to detecting alcohol craving and assessing change in craving as it relates to relapse during treatment. Next, we examine the experimental paradigms that have been used to induce alcohol craving in the laboratory. Further, the methodological issues affecting laboratory-based paradigms are presented, while also elucidating the potential use of effective laboratory-based craving induction paradigms, both in clinical studies as well as in laboratory studies that examine the brain mechanisms associated with the concept of craving. Finally, directions for future research on craving in the laboratory and the clinic are presented in the context of developing more effective treatments for different phases of recovery from alcohol dependence. 相似文献
69.
Central pathways transmit pain from peripheral regions to one of the most important area of the descending pain modulatory system, the Periaqueductal gray (PAG). Independent discoveries in the past suggest that the PAG contains afferent input, output neurons and intrinsic interneurons. An attempt was made in the present study to find out the effects of more than one kind of noxious stimulus on the PAG neuronal activity. Experiments were conducted in rhesus monkeys and the effects of noxious mechanical, thermal and tooth-pulp stimulation on the activity of 14 neurons were studied. The neurons responded to more than one kind of noxious stimuli by increasing or decreasing its firing rate. No limb specificity could be identified and homogeneous distribution of the excitatory and inhibitory neurons was found. 相似文献
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