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Evidences for the formation of the glutathione-hydroxyellipticine adduct during the rat metabolism of 9-methoxyellipticine are provided. These data suggest that such a cytotoxic molecule might behave as a pro-alkylating agent in vivo.  相似文献   
194.
Abstract. 1. Desiccation tolerance and starvation resistance demonstrated significant differentiation among seven Indian geographical populations of Drosophila kikkawai, collected along a latitudinal range of 12.6–32.7 °N. Lack of significant differences in two successive generations suggested that these physiological traits were genetically controlled. 2. North Indian populations of D. kikkawai displayed significantly higher desiccation tolerance than southern populations, whereas there was a reverse trend for starvation tolerance (r > 0.90). Regression slope values indicated an increase of 0.61 h for desiccation and a decrease of 1.71 h per degree latitude for starvation tolerance at 17 °C. The traits evidenced opposite latitudinal clines, and such data also matched thermal climatic conditions on the Indian subcontinent. The survival duration for such traits was significantly higher at 17 than at 25 °C. 3. Significantly higher starvation tolerance in south Indian populations might be due to large population size, species interactions, and higher metabolic rates in the humid tropical environments. In contrast, prolonged unfavourable colder climatic conditions are known to favour starvation tolerance in temperate regions. Thus, the causes of desiccation and starvation tolerance seem quite different under tropical and temperate conditions. 4. Starvation tolerance was correlated negatively with body weight and ovariole number, which might be due to a trade-off in favour of greater allocation to non-lipidic reserves for sustaining starvation tolerance in the tropics. Reduction in metabolic rate may not be applicable for observed higher starvation tolerance in the tropical populations. 5. Multiple regression analysis demonstrated a major effect of coefficient of variation of mean monthly temperature for both the traits of ecological significance. Thus, Indian geographical populations of D. kikkawai provided evidence of independent genetic divergence for starvation and desiccation tolerance under natural conditions.  相似文献   
195.
Psoriatic human hair-follicle keratinocytes were cultured and then examined using light and electron microscopy. In comparison to control cultures derived from non-psoriatics, there were significant differences: stratification in general was more extensive; suprabasal cells were flat instead of round; there were almost no depositions of basal lamina or of cellular debris on the growth substrate; numerous membrane coating granules and a few keratohyalin granules were present earlier in psoriatic cultures than in control cultures; and the differentiation pattern resulted in an earlier appearance of corneocyte-like cells, and clusters of these corneocyte-like cells appeared to have been shed into the culture medium. As in control cultures, no distinct stratum corneum was found. Whether these differences between psoriatic cultures and control cultures reveal an aberrant differentiation pattern for psoriatic cells in vitro is as yet unknown: due to the faster outgrowth in psoriatic cultures, a multilayered and therefore further-differentiated structure near the hair follicle could be obtained more rapidly in psoriatic than in normal skin.  相似文献   
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ABSTRACT: BACKGROUND: Cirrhosis produces variety of symptoms which eventually lead to a negative impact on Health Related Quality of Life (HRQOL). The general aim of this study was to evaluate the magnitude of poor HRQOL and to assess factors related with HRQOL in patients with CLD in Pakistan. FINDINGS: This was a cross sectional study conducted in gastroenterology outpatient clinics of Aga Khan University Hospital, Karachi on adult patients with cirrhosis. In this study chronic liver disease questionnaire (CLDQ) was used to assess HRQOL of these patients and CLDQ score was used as an outcome measure to determine factors related with HRQOL. 273 participants were recruited in the study; 155 (57%) were males. Mean age of participants was 49 [PLUS-MINUS SIGN] 11 years. The most common cause for cirrhosis was viral infection 247(91.5%). Mean Model for End Stage Liver Disease (MELD) score was 12.6 [PLUS-MINUS SIGN] 6.8 and 2/3 of patients 209 (76.6%) had advanced cirrhosis in Child Turcot Pugh (CTP) B or C stage. Poor HRQOL was seen in 187(69%; 95% C.I.: 63%, 74%) of the participants. Mean CLDQ score was 4.36 [PLUS-MINUS SIGN]1.1. Amongst all of the domains, fatigue domain had lower CLDQ score. Hemoglobin (beta = 0.09 [SE = 0.04]), Albumin (beta = 0.32[SE = 0.09]), Diastolic Blood Pressure (DBP) (beta = 0.01[0.005) prior history of decompensation (beta = 0.98[SE = 0.39] were significant factors associated with HRQOL in patients with liver cirrhosis. CONCLUSION: Frequency of poor health related quality of life determined by CLDQ score is high in patients with liver cirrhosis. Hemoglobin, serum albumen, prior history of decompensation (like encephalopathy and upper gastro intestinal bleed), are associated with health related quality of life.  相似文献   
198.
Om Parkash Mittal 《Genetica》1970,41(1):575-580
The haploid number of chromosomes inStegodyphus sarasinorum (Eresidae) andUloborus plumipes (Uloboridae) is thirteen (11+X1X2) and ten (8+X1X2) respectively. The sex-chromosomes are of equal size in the former and unequal in the latter. All chromosomes are acrocentric in both species.  相似文献   
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