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31.
Infertility among couples in Egypt is causing increasing concern. Investigations showed a relationship between ovulatory disorders and the incidence of female factor-mediated fertility difficulties in couples. However, the factors responsible for the sudden increase in ovulatory disorders are not fully understood. The aim of this study was to assess the presence of aflatoxin in sera of infertile women and to correlate this with ovarian functions and hormonal parameters. Blood samples were collected from 70 adult Egyptian females comprising 50 infertile and 20 fertile control individuals, and screened for the presence of aflatoxin B1 (AFB1). Ovarian function was examined by measuring mean ovarian volume, and the umber and size of ovarian follicles. Blood hormonal levels were determined. All blood samples (patients and controls) showed negative results as regards AFB1 analysis. However, there was a significant enlargement in the mean ovarian volume but a significant decrease in follicular size. In addition, there were significant higher levels of lutinizing hormone (LH) and significant lower levels of mid-luteal progesterone in infertile females. Although blood samples were negative with respect to AFB1, the role of aflatoxin cannot be excluded as a contributing factor to female infertility, since the toxin was found to produce deleterious effects on the reproductive system in animals. More studies including aflatoxin analysis in ovarian biopsies are recommended to ascertain involvement of this toxin.  相似文献   
32.
The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera (Htibner), fed on cotton bolls grown under elevated CO2 (double-ambient vs. ambient) in open-top chambers were examined. Significant decreases in protein, total amino acid, water and nitrogen content and increases in free fatty acid were observed in cotton bolls. Changes in quality of cotton bolls affected the growth, development and food utilization of H. armigera. Significantly longer larval development duration in three successive generations and lower pupal weight of the second and third generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower fecundity was also found in successive three generations of H. armigera fed on cotton bolls grown under elevated CO2. The consumption per larva occurred significant increase in successive three generations and frass per larva were also significantly increased during the second and third generations under elevated CO2. Significantly lower relative growth rate, efficiency of conversion of ingested food and significant higher relative consumption rate in successive three generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower potential female fecundity, larval numbers and population consumption were found in the second and third generations of cotton bollworm fed on cotton bolls grown under elevated CO2. The integrative effect of higher larval mortality rate and lower adult fecundity resulted in significant decreases in potential population consumption in the latter two generations. The results show that elevated CO2 adversely affects cotton bolls quality, which indicates the potential population dynamics and potential population consumption of cotton bollworm will alleviate the harm to the plants in the future rising CO2 atmosphere.  相似文献   
33.
羧基化多壁碳纳米管对雌性小鼠卵泡发育的影响   总被引:1,自引:0,他引:1  
碳纳米管(carbon nanotubes, CNTs)作为一种新形式的结晶碳,在工业及医药领域具有非常广阔的应用前景。本研究采用水溶性较好的羧基化多壁碳纳米管(MWCNTs-COOH)为研究对象,探索功能化多壁碳纳米管对小鼠卵巢发育的影响。将羧基化多壁碳纳米管溶解在含0.5% Tween-20的磷酸盐缓冲溶液(PBS)中,对实验小鼠按照2.5, 5, 10 mg·kg-1进行持续64 d的灌胃处理。处理结束后通过透射电子显微镜和HE染色观察卵巢组织的形态学变化。结果显示,碳纳米管确实进入了小鼠卵巢中。同时,随着MWCNTs-COOH暴露的增加,雌性小鼠卵泡数量显著减少,而雌性小鼠卵泡的形态结构并无明显影响。  相似文献   
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