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91.
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
92.
93.
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
94.
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
95.
The popularization and application of cold storage red blood cells or whole blood at −80 °C of the Rh(D) negative patients in surgical operation 总被引:2,自引:0,他引:2
Summary The efficiency of cold storage red blood cells (CSRBC) or whole blood at −80 °C used in 27 Rh(D) negative patients during
surgical operation was reported. The Rh(D) negative patients received the transfusion of CSRBC or whole blood stored at −80
°C for 180 to 360 days. The changes in the indexes, such as blood TB, DB, K+, Na+, BUN, Cr, urine protein (URPO), UOB, Hb, HCT, serum total protein, relative to hemolytic reaction and blood volume before
and after transfusion were observed. The results showed that after transfusion of CSRBC or whole blood 27 cases were negative
for urine protein and UOB, and the levels of BUN and Cr were normal (P>0.05). Blood TB, DB, Hb, and HCT were increased, while pH, blood K+ and blood Na+ was normal with the difference being not significant before and after operation (P>0.05). Plasma protein was decreased, but there was no significant difference before and after operation (P>0.05). It was suggested that CSRBC or whole blood at −80 °C could be safely infused to the Rh(D) negative patients without
side effects during the surgical operation.
YU Zhongqing, male, born in 1957, Technician in Charge 相似文献
96.
Nine pedunculated benign synoviomata causing mechanical symptoms similar to those of a torn meniscus are described. The average age of the patients was 34.4 years. During the period of study, 2254 meniscal lesions causing mechanical symptoms were identified, giving an incidence of one benign synovioma for every 250 meniscal lesions. All the lesions were removed arthroscopically with relief of symptoms. 相似文献
97.
Tadimeti S. Rao Karen D. Lariosa-Willingham Fen-Fen Lin Naichen Yu Chui-Se Tham Jerold Chun Michael Webb 《International journal of developmental neuroscience》2004,22(3):131-135
Reactive gliosis is an aspect of neural plasticity and growth factor (GF) stimulation of astrocytes in vitro is widely regarded as a model system to study astrocyte plasticity. Astrocytes express receptors for several ligands including lysophosphatidic acid (LPA) and sphingosine-1-phosphate (S1P), agonists for the G-protein-coupled lysophospholipid receptors (lpRs). Activation of lpRs by LPA or S1P leads to multiple pharmacological effects including the influx of calcium, phosphoinositide (PI) hydrolysis, phosphorylation of extracellular receptor regulated kinase (ERK), release of arachidonic acid, and induces mitogenesis. Treatment of astrocytes in vitro with a growth factor cocktail (containing epidermal growth factor [EGF], basic fibroblast growth factor [bFGF] and insulin) led to a marked attenuation of lpR-induced PI hydrolysis. In contrast, under identical conditions, GF treatment led to marked potentiation of PI hydrolysis downstream of activation of another abundantly expressed G-protein coupled receptor, mGluR5. Quantitative gene expression analysis of GF-treated or control astrocytes by TaqMan RT-PCR indicated that GF treatment did not change gene expression of lpa1 and s1p1, but increased gene expression of s1p5 which is expressed at very low levels in basal conditions. These results suggest that GF differentially affected PLC activation downstream of mGluR5 versus lpR activation and that the changes in mRNA levels of lpRs do not account for marked attenuation of agonist-induced phosphoinositide turnover. 相似文献
98.
Long-term effects of physiologic concentrations of dexamethasone on human bone-derived cells 总被引:2,自引:0,他引:2
M M Wong L G Rao H Ly L Hamilton J Tong W Sturtridge R McBroom J E Aubin T M Murray 《Journal of bone and mineral research》1990,5(8):803-813
Bone cells derived from human trabecular explants display osteoblastic features. We examined the modulation of alkaline phosphatase activity and cAMP production as the result of exposing trabecular explants to physiologic concentrations of dexamethasone for 4 weeks during cellular outgrowth and subculture. Cells treated with dexamethasone were observed to grow generally more slowly than control cells. Cells appeared larger and more polygonal, and staining for alkaline phosphatase was more intense in the dexamethasone-exposed cultures. There was a progressive increase in cellular PTH responsiveness with increasing duration of exposure of cells to dexamethasone. Cells grown for 6 weeks in 3 x 10(-8) M dexamethasone had a 10-fold increase in PTH-stimulated cyclic AMP accumulation. Dexamethasone-treated cells also had a significantly increased alkaline phosphatase activity. 1,25-(OH)2D3-stimulated alkaline phosphatase activity was increased approximately 20-fold. cAMP responses were significantly increased to PTH (21.7-fold), PGE1 (2.67-fold), and forskolin (4.81-fold), but not to cholera toxin. Dexamethasone-treated cells also had a mean decrease in 1,25-(OH)2D3-stimulated osteocalcin production to 26.2% of control values (p less than 0.001). Hydrocortisone treatment gave rise to similar effects but of smaller magnitude than those of dexamethasone. Testosterone did not have a significant effect on alkaline phosphatase activity or cAMP production. Skin fibroblasts showed a significant enhancement of alkaline phosphatase activity in response to dexamethasone, but of a much smaller magnitude than in bone cells. The phenotypic changes induced by long-term culture in dexamethasone are consistent with the promotion of a more differentiated osteoblastic phenotype. 相似文献
99.
粉防己碱与牛磺酸合用对血小板聚集与血栓形成的影响 总被引:4,自引:0,他引:4
粉防己碱(Tet)和牛磺酸(Tau)均能抑制ADP、胶原和凝血酶诱导的大鼠血小板聚集及血栓形成。Tet抑制ADP诱导聚集较强,Tau则对胶原作用最明显,二药减半量合并应用时,较各药单用强 相似文献
100.
报告16例大肝癌手术切除治疗效果,癌块直径>7cm。其中巨块型12例,癌块>10cm9例;癌块>14cm3例,均经病理证实。Ⅱ期切除3例,均经肝固有动脉结扎加插管注药化疗,肿块缩小后再手术,术后生存1年4例,2年3例,3年4例,4年1例,全组中位生存期24.1个月,并对大肝癌的手术适应证及术式选择等进行了探讨。 相似文献