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991.
Induction of gastric tumor and intestinal metaplasia in rats exposed to localized X-irradiation of the gastric region 总被引:2,自引:0,他引:2
The induction of gastric tumor and intestinal metaplasia was examined in 8-week-old male JCL/SD rats exposed to localized X-irradiation of the gastric region. The animals were each given two 20 Gy fractions of X-rays, with a one-week interval between fractions (total, 40 Gy). Nine atypical hyperplasias (20%) and 13 adenocarcinomas (28%) in the pyloric mucosa of the glandular stomach were found in 46 animals with X-irradiation. The incidence of intestinal metaplasia was 93% in the pyloric mucosa, 50% in the fundic mucosa and 96% in both the pyloric and fundic mucosa. Type B metaplasia (intestinal metaplasia without Paneth cells) was most common and type C (intestinal metaplasia with Paneth cells) was less frequent. No gastric tumor or intestinal metaplasia appeared in non-irradiated control rats. This study shows that local X-irradiation of the gastric region induced both gastric tumor and intestinal metaplasia independently. 相似文献
992.
A Ponge J M Mussini T Ponge Y Maugars S Cottin 《La Revue de médecine interne / fondée ... par la Société nationale francaise de médecine interne》1987,8(3):251-256
In a retrospective study covering 11 years, 59 adult cases of dermatomyositis or polymyositis were reviewed. The disease was of paraneoplastic origin in 9 cases (15,25 p. 100), the same proportion as that found in the literature (14,6 p.100). The striking female predominance (8/9 cases) and the patients' mean age (61.11 years) were higher than those noted in non-paraneoplastic dermato- and polymyositis in adults (female predominance 34/50, mean age 52.9 years). Clinically, out of 9 patients 7 had dermatomyositis and 2 had polymyositis. The disease was discovered at the same time as the neoplasia in 7 of the 9 cases. Muscle histology showed that in contrast with non-paraneoplastic cases of dermatomyositis-polymyositis those of paraneoplastic origin had moderate lesions without fibrosis. 相似文献
993.
Antiherpes activity of chemically synthesized lipid A-subunit analogue GLA-60 in immunosuppressed mice 总被引:4,自引:0,他引:4
Intraperitoneal administration of 10 micrograms GLA-60, a chemically synthesized lipid A analogue, to mice one day after treatment with 200 mg/kg of cyclophosphamide (CY) significantly increased the number of macrophages, lymphocytes and polymorphonuclear leukocytes (PMNs) in the peritoneal cavity. The intrinsic antiviral activity of macrophages against herpes simplex virus type 1 (HSV-1) as well as natural killer (NK) activity against YAC-1 target cells was stimulated by administration of GLA-60 to CY-immunosuppressed mice. When the mice were administered GLA-60 prior to HSV-1 infection, virus growth was inhibited and the mortality rate of infected mice was reduced. Thus, GLA-60 is a potent immunomodulator achieving its antiviral action through enhancement of nonspecific host defense mechanisms. Combined treatment of GLA-60 with the antiviral agent acyclovir (ACV) resulted in greater protection against HSV-1 in the CY-immunosuppressed mice than did single treatment with either GLA-60 or ACV. 相似文献
994.
Metabolic and morphological alterations of brown adipose tissue after sympathetic denervation in rats 总被引:2,自引:0,他引:2
Effects of sympathetic denervation on biochemical and morphological changes of brown adipose tissue (BAT) were studied in rats after severing 5 intercostal nerve bundles that enter the unilateral interscapular BAT, the contralateral BAT being used as the control. Four weeks after denervation, there was no appreciable change in BAT weight or its DNA and protein contents, whereas the triglyceride content was increased significantly. However, the rate of fatty acid synthesis was decreased to about half the rate in controls. The denervated BAT was much paler than controls and contained lots of adipocytes filled with large lipid droplets, some of which were unilocular. The results are discussed with reference to changes in BAT seen after bilateral lesions of the ventromedial hypothalamus. 相似文献
995.
The absorption and excretion and clinical effectiveness of cefixime (CFIX) granules, a new oral cephalosporin, were studied with pediatric patients with tonsillitis and urinary tract infection (UTI). Peak serum concentrations in 3 children given orally a single dose of 3 mg/kg on fasting were 0.545 micrograms/ml at 2 hours in 1 patient, and 1.56 and 1.26 micrograms/ml at 4 hours in the other 2. The half-lives in the 3 patients were 3.21-3.42 hours, with an average of 3.29 hours. The urinary concentration during the first 6 hours was 36.5 micrograms/ml in 1 patient showing the low serum level, and the first 6-hour urinary recovery rate was 7.3%. In the other 2 patients, urinary concentrations and recovery rates up to 6 hours were 87 and 62 micrograms/ml, and 17.0 and 15.1%, respectively. The second 6-hour urinary concentrations and recovery rates were 35.5 and 20.8 micrograms/ml, and 12.7 and 8.8%, respectively. The urinary recovery rates up to 12 hours were 29.7 and 23.9%, respectively. CFIX was given orally to 19 children with 20 diseases in daily doses of 6.4-12.9 mg/kg in 2 or 3 divided portions for 3 to 12 days. Clinical evaluations were made on 18 diseases. Clinical effects of CFIX were excellent in 4, good in 7 and poor in 1 of the 12 patients with tonsillitis, and excellent in 5 and good in 1 of the 6 patients with UTI. The overall clinical effectiveness rate was 94.4%. No side effects were observed in any of the 19 patients. Hematological tests, showed slight elevation of blood platelet counts in 2 patients.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
996.
997.
998.
Changes in the levels of urea cycle enzymes and polyamine metabolism in the liver of rats treated with alpha-naphthylisothiocyanate (ANIT), an inducer of experimental cholestasis, were studied. Activities of arginase increased approximately two-fold compared to the control values during the period of 24-72 hours after oral administration of ANIT (100 mg/kg), while activities of ornithine carbamyltransferase and ornithine aminotransferase decreased. The activity of ornithine decarboxylase was elevated by approximately 20- and 10-fold at 12 and 60 hours, respectively, after ANIT administration. Putrescine concentration doubled 24-48 hours after the ANIT administration, but spermidine level rose more slowly and reached the level of 1.5-fold of the control level in 36-72 hours. Spermine concentration decreased initially but increased in 96 hours. These results suggest that the increased activity of urea cycle accounts for the increase in the ornithine content and that the putrescine and spermidine acts as the initiator of recovery of the liver damaged by ANIT treatment. 相似文献
999.
Three patients with malignant lymphoma, two of T-cell type and the other probably also of T-cell type, had an interstitial deletion of the short arm of chromosome 6, del (6)(p21p23), in common in their lymphoma cells. These findings suggest that this new type of chromosome deletion may be a specific marker for T-cell lymphoma and may play an important role in the lymphomagenesis and the expression of the T-cell phenotype. 相似文献
1000.
Immunobiology of human gliomas 总被引:5,自引:0,他引:5