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91.
92.
P. Meera P. R. Rao R. Shanker O. Tripathi 《Immunopharmacology and immunotoxicology》1992,14(1):261-282
Mice were fed for 24 weeks with three different subtoxic dosages of γ-HCH (0.012, 0.12 and 1.2 mg/kg) mixed in powdered feed. The immunological profile was assessed at an interval of one month during the entire exposure period. Both the cell mediated and humoral components of immunity showed a biphasic response characterized initially by stimulation followed by suppression in a dose dependent manner. However, γ-HCH did not affect the functional properties of peritoneal macrophages. Histological changes in lymphoid organs were in accordance with the biphasic immunomodulatory effects of γ -HCH. 相似文献
93.
94.
L’incontinence fécale est un problème fréquent en pratique médicale mais souvent sous-estimé et mal traité. Cet artiele revoit l’épidémiologie, les mécanismes pathophysiologiques et les approaches diagnostiques des patients souffrant d’incontinence fécale. De plus, je ferai une synthèse des traitements médicaux de l’incontinence fécale. Une anamnèse systématique et une étude de la morphologie et de la physiologie anorectales permet souvent de mettre en évidence les mécanismes pathogéniques sous-jacents et d’orienter le traitement. 相似文献
95.
Summary. Parameters were obtained from the reproductive organs of ethanol-fed, gossypol-treated Sprague Dawley rats. The experimental animals were fed either on a normal (15.17%) or low protein (8.00%) diet. Measurements included reproductive organ weights, seminal characteristics, serum concentration of testosterone and histological, stereological and histomorphometric evaluation of the testis. The testis size, length and diameter of the seminiferous tubule had the least values in the protein-malnourished, gossy-pol-treated rats (3.01±0.26 g, 0.56 ± 0.03 m, 281.34±11.30 μn), in comparison to corresponding animals which had received ethanol simultaneously with gossypol (3.40 ± 0.25, 0.71±0.06m, 314.42 ± 11.61 μn). As gossypol and ethanol are both associated with reduced reproductive capacity, this unexpected but interesting finding lends support to the hypothesis that either a normal dietary protein or ethanol consumption may modify the action of gossypol on body tissues, including the testis. This effect, presumably mediated through changes caused to the bioavailability of gossypol, modifies its antifertility activity. The present observation further highlights the need to consider the concurrent administration of other drugs, such as alcohol, and the nutritional status in the evaluation of gossypol for various potential uses. 相似文献
96.
The incidence of spontaneous Leydig cell tumors of testis is very high in old F-344 rats. We have examined the effect of dehydroepiandrosterone (DHEA), a steroid hormone with antimitotic and anticarcinogenic properties, on spontaneous Leydig cell tumorigenesis. Fifteen-week-old male F-344 rats were fed a diet containing DHEA (0.45% w/w) for 84 weeks. At the termination of experiment none of the 13 rats had Leydig cell hyperplasia or Leydig cell tumors. All the eight control rats of comparable age had Leydig cell tumors. These findings suggest that DHEA is a potent inhibitor of spontaneous Leydig cell tumors of testis in aged rats. 相似文献
97.
J E Gervasoni R N Taub M T Yu D Warburton M Sabbath S Gilleran D L Coppock J D'Alessandri S Krishna M Rosado 《Cancer research》1992,52(19):5244-5249
Anthracycline-resistant HL-60/AR cells and their drug-sensitive HL-60/S counterparts were characterized by karyotypic analysis and examined for the overexpression of DNA and mRNA sequences coding for P-glycoprotein (Pgp). The HL-60/S cells were karyotypically stable over a 5-year period of study (1986-1991), except for an additional small Giemsa-positive band noted at 7q22 in cultures harvested in 1987, but not in 1986. This change did not affect drug sensitivity. The drug-resistant HL-60/AR cells examined in 1986, 1987, and 1991 demonstrated a very stable karyotype. The most striking feature was a large homogeneously staining region in the long arm of chromosome 7 (7q11.2), and translocation of the remainder of the long arm to another centromere. Other changes in the HL-60/AR cells included inversion in 9q, partial deletion of the short arm of chromosome 10p, addition of material to the p arm of der(16), loss of chromosome 22, and the appearance of a new marker chromosome. Both HL-60/S and the HL-60/AR cells were found not to amplify DNA or mRNA sequences coding for the Pgp. Thus, although the HL-60/AR cells possess the classical multidrug resistance phenotype and demonstrate a homogeneously staining region near the region of the MDR1 gene, their resistance is due to mechanisms other than those coded for by MDR1. 相似文献
98.
99.
A K Rama Krishna Shivanand Patil Grs Srinivas Rao Ajit Kumar 《Indian journal of gastroenterology》2006,25(2):97-98
Gastrointestinal manifestations of dengue fever are mainly in the form of bleeding or liver function abnormalities. Dengue fever presenting as acute colitis-like picture is not reported to date. We report a 50-year-old man with dengue fever presenting with lower gastrointestinal bleeding and colonoscopic features of acute inflammatory colitis. 相似文献
100.
M S Rao M M Mangino M I Usman V Subbarao D G Scarpelli M K Reddy J K Reddy 《Cancer research》1987,47(6):1657-1662
In this study we have investigated the effect of a single dose of tannic acid, administered s.c., on the nucleolar ultrastructure of hepatocytes transplanted into a syngeneic or xenogeneic host in order to evaluate the validity of our hepatocyte transplantation system as an in vivo alternative to the use of whole animals to test for species and strain differences to the effects of hepatotoxins. Within 4-6 h following tannic acid injection, rat hepatocytes transplanted into the anterior chamber of eye and inguinal fat pads of rat and athymic nude mouse, showed changes of nucleolar components, with separation of ribonucleoprotein containing granules into discrete dark zones. These dark areas were surrounded by light areas consisting of granular and fibrillar components of the nucleolus. These changes were identical to tannic acid-induced nucleolar alterations in the homotopic liver. Hamster and rat hepatocytes xenotransplanted into athymic nude mice also displayed prominent nucleolar alterations in response to tannic acid. The similarity and extent of nucleolar alterations observed in transplanted hepatocytes and the in situ homotopic liver cells attest to the usefulness of the hepatocyte transplantation system for the evaluation of species differences in biological response to toxic/carcinogenic effects of xenobiotics. 相似文献