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911.
Glutamine synthetase (GS) is a marker enzyme for Müller glia cells in neural retina. In chick embryo retina GS begins to increase sharply on the 16th day of development, but can be precociously induced by premature supply of the inducer, cortisol, already on the 8th day. At this stage GS inducibility is low, but it increases progressively with embryonic age. We investigated whether there was a corresponding age-dependent increase of cortisol-binding molecules (cortisol receptors) and found that their level is highest in the early retina and decreases with development. In light of this inverse relationship, we examined whether functional characteristics of these receptors change with age, but detected no differences. In in vitro tests, receptors from older retina translocated cortisol into nuclei from young retina, and vice versa, with similar effectiveness. Also, cortisol receptors from liver cells (which differ from retina receptors) can translocate the hormone into retina nuclei, and vice versa. These findings indicate that translocation of cortisol receptors is neither tissue-specific or age-dependent, nor is it conditional on the total amount of receptors normally present in cells. Therefore, the age-dependent increase of GS inducibility in embryonic retina cannot be directly related to quantitative or functional differences of cortisol receptors and is evidently controlled primarily at the gene level. The very large amount of cortisol-binding molecules in early embryonic retina raises the possibility that they play some role in early differentiation of retina cells unrelated to hormone binding. 相似文献
912.
913.
Ching Mun Kok Chin Chin Sieo Hui Yin Tan Wan Zuhainis Saad Juan Boo Liang Yin Wan Ho 《Journal of microbiology (Seoul, Korea)》2013,51(5):700-703
The effect of Leucaena leucocephala hybrid-Bahru (LLB), which contains a high concentration of condensed tannins, on cellulolytic rumen fungal population in goats was investigated using real-time PCR. The fungal population in goats fed LLB was inhibited during the first 10 days of feeding, but after 15 days of feeding, there was a tremendous increase of fungal population (157.0 μg/ml), which was about fourfold more than that in control goats (39.7 μg/ml). However, after this period, the fungal population decreased continuously, and at 30 days of feeding, the fungal population (50.6 μg/ml) was not significantly different from that in control goats (55.4 μg/ml). 相似文献
914.
M. F. Saad W. C. Knowler D. J. Pettitt R. G. Nelson P. H. Bennett 《BMJ (Clinical research ed.)》1988,297(6661):1438
As part of a continuing epidemiological study of non-insulin dependent diabetes among Pima Indians 154 subjects who had had a transient impairment of glucose tolerance were followed up for 1.2-16.9 (median 5.8) years after their glucose tolerance had returned to normal. Of these, 49 subsequently developed diabetes; 26 subsequently developed impaired glucose tolerance; and 79 had normal glucose tolerance at the last examination. The cumulative incidence of diabetes was 16% and 48% at five and 10 years of follow up respectively, compared with 3% and 8% for a control group of 1245 members of the same population. After adjustment for age, sex, body mass index, and plasma glucose concentration two hours after glucose loading the incidence of diabetes among the subjects who had had transient impaired glucose tolerance was 3.0 times that among the controls (95% confidence interval 2.1 to 4.3). Proportional hazards function analysis indicated that obesity was the most important predictor of subsequent development of diabetes. The results suggest that transient impairment of glucose tolerance indicates, at least in some subjects, a predisposition to diabetes and should not be considered clinically unimportant. 相似文献
915.
916.
Mounir Ajina Amira Zairi Soumaya Mougou Samira Ibalaa Radhouène Naiefer Ghaya Merdassi Mariem Mehdi Khaled El Heni Ali Saad 《Andrologie》2005,15(1):53-61
The spermicidal efficacy of synthetic peptides, dermaseptin (DS1) and (DS4), was studied under in vitro conditions using human spermatozoa. The data showed that sperm motility was inhibited with various concentrations of dermaseptins at different intervals ranging from 2 to 240 min. The effective 100% inhibitory concentration (EC100) of DS4 sperm immobilization assay was equal to 50 mg/ml at 30 min, while the EC 100 of DS1 was equal to 100 mg/ml. The presence of 0.1% of chelating agent, EDTA, reduced the EC100 of DS4 to 5 mg/ml, while less than a twofold enhancement in DS 1 activity was observed in combination with EDTA. The action of dermaseptins on sperm motility was observed to be dose-dependent. Addition of pentoxifylline, which is known to enhance sperm motility, and Ca2+, which is a key element for sperm movement, did not prevent the spermicidal action of dermaseptins. 相似文献
917.
918.
Ahmed Chouket Mounir Lefi Abdelkader Bouhlel Abdelahad Ounaies Hamadi Saad 《Andrologie》2007,17(1):88-94
The combination of seminal vesicle cyst and homolateral renal agenesis is a rare congenital anomaly. However, this anomaly is diagnosed more frequently due to progress in medical imaging. The authors report three cases of seminal vesicle cyst associated with ipsilateral renal agenesis in two cases and ectopic ureter in one case. All cases presented nonspecific clinical symptoms. The diagnosis was suspected on imaging (ultrasound and computed tomography). Treatment was surgical in two cases and endoscopie in one case. The authors review the literature on the aetiology and pathogenesis of seminal vesicle cyst, its association with homolateral renal agenesis and diagnostic and therapeutic methods. 相似文献
919.
920.
Dilly OC Anumba Saad El Gelany Sarah L Elliott Tin C Li 《Reproductive biology and endocrinology : RB&E》2010,8(1):62