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91.
Methimazole (MMI) (>0.1 mmol kg(-1), p.o.) given in combination with DL-buthionine sulphoximine (BSO) (3 mmol kg(-1), i.p., 1 h before MMI administration), an inhibitor of glutathione (GSH) synthesis, caused liver injury in mice. The injury was characterized by centrilobular necrosis of hepatocytes and an increase in serum alanine transaminase (ALT) activity. Methionazole (2 mmol kg(-1)) alone resulted in only a marginal increase in serum ALT activity, but produced no histopathological changes in the liver. Pretreatment with hepatic cytochrome P-450 monooxygenase inhibitors--cobalt chloride, isosafrole, methoxsalen, metyrapone and piperonyl butoxide-prevented or tended to suppress the hepatotoxicity induced by MMI in combination with BSO. Treatment with N,N-dimethylaniline and ethyl methyl sulphide, competitive substrates of flavin-containing monooxygenases (FMO), also resulted in remarkable suppression of the hepatotoxicity caused by MMI in combination with BSO. These results suggest that MMI is activated by reactions mediated by both cytochrome P-450 monooxygenases and FMO, and that the inadequate rates of detoxification of the resulting metabolite are responsible for the hepatotoxicity in GSH-depleted mice.  相似文献   
92.
Pregnant rats were given 0%-, 5%-, 10%- and 20% ethyl alcohol in drinking water during the gestation period.We evaluated the brain function of pups born of alcohol-administered dams. Learning ability (Sidman avoidance behavior), the amounts of monoamines (noradrenalin, dopamine, serotonin) and metabolites (3,4-dihydroxyphenyl acetic acid [DOPAC], homovanillic acid [HVA] and 5-hydroxyindole acetic acid [5-HIAA])in whole brain were examined for neurobehavioral and neurochemical effects.There was no effect on Sidman avoidance behavior in 56-day-old offspring, but alterations of the amounts of monoamines and their metabolites were observed even in 66-day-old offspring as a result of the dams' exposure to ethanol during pregnancy.  相似文献   
93.
Breast conserving surgery and radiation therapy (RT) can achieve a more favorable cosmetic outcome than mastectomy in patients with early breast cancer. However, it is widely recognized that RT is an impediment to improving the cosmetic outcome. Between 1985 and 1993, 113 patients were enrolled in a prospective randomized study to examine whether or not RT could be avoided following sector resection in patients with Stage I and II (UICC) invasive breast cancer. There was no significant difference in the 8 year local recurrence free survival rate between the RT and non-RT groups (92.3% versus 89.8% respectively). The characteristics of suitable patients would be negative nodes and microscopically negative resection margins. In conclusion, sector resection without RT is a reasonable option for some patients with early breast cancer.  相似文献   
94.
The clinical efficacy, dose-response relationship, and safety of TRH-T (thyrotropin releasing hormone tartrate) were assessed in 290 patients with spinocerebellar degeneration (SCD) in a 2-week, double-blind study using placebo as control. 254 patients satisfied the criteria for inclusion in evaluation of the drug efficacy. The patients were treated with TRH-T in an intramuscular dose of 2 mg, 0.5 mg or 0 mg (placebo) as TRH once a day for 2 weeks. Clinical responses to these treatments were evaluated 3 times: at the end of weeks 1 and 2 of treatment and a week after the end of treatment. The results of "global improvement rating" as well as those of "ataxia improvement rating" showed that both 2 mg and 0.5 mg TRH-T treatments were significantly superior to placebo treatment in patients with predominantly cerebellar form of SCD. The effect was well maintained a week after the end of the 2-week treatment in the patients who were given TRH-T in daily dose of 2 mg and showed improvement at the end of treatment. The results of "improvement rating of each symptom" revealed that 2 mg treatment was significantly more effective than placebo for disorders of standing, gait, speech and writing. In the patients who had no pyramidal involvement or disorder of deep sensation, the drug efficacy and dose-response relationship were evident. Adverse reactions to the drug such as headache, feeling febrile and nausea were observed in 50% of the patients on 2 mg treatment, in 38% of those on 0.5 mg treatment and in 21% of those on placebo patient, however, discontinued treatment because of adverse reactions.  相似文献   
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Objective: To evaluate the effect of prednisolone plus low-dose aspirin (PSL/LDA) in women with autoimmune conditions who were enrolled in an IVF-ET program.

Design: A retrospective clinical study.

Setting: In vitro fertilization unit, Niigata University Hospital, Niigata, Japan.

Patient(s): Three hundred seven women who underwent IVF-ET between January 1996 and December 1997.

Intervention(s): Prednisolone (10 mg/d) and aspirin (81 mg/d) were administered to the women with autoantibodies who chose to participate.

Main Outcome Measure(s): Pregnancy and implantation rates with IVF-ET.

Result(s): Women undergoing IVF who had positive antinuclear antibodies, with or without antiphospholipid antibodies, had significantly lower pregnancy and implantation rates than did women without autoantibodies (14.8% versus 21.7% and 6.8% versus 10.4%, respectively). The administration of PSL/LDA to women with antinuclear antibodies significantly improved the outcome of IVF-ET (40.6% pregnancy rate and 20.3% implantation rate).

Conclusion(s): A high proportion of women who are undergoing IVF-ET have autoantibodies, which are associated with poor IVF outcomes. The administration of PSL/LDA to these women may improve their implantation rate.  相似文献   

99.
We have recently found a novel cell-cell adhesion system at cadherin-based adherens junctions. This system consists of at least two components: nectin, an immunoglobulin-like cell adhesion molecule with Ca(2+)-independent homophilic binding activity, and l-afadin, an actin filament-binding protein that connects nectin to the actin cytoskeleton. In the present study, we investigated immunocytochemically the localization of l-afadin in the mouse hippocampus. At the light microscopic level, l-afadin immunoreactivity was demonstrated as flattened disks in the stratum lucidum of the CA3 area. By immunoelectron microscopy, signals for l-afadin were highly concentrated in a symmetrical manner at the puncta adhaerentia-like junctions between the mossy fiber terminals and the dendritic trunks of pyramidal cells. We furthermore immunostained the hippocampus with antibodies recognizing both l-afadin and s-afadin, a small splicing variant of l-afadin that is identical to AF-6. Immunoreactivity for l- and s-afadins was demonstrated not only as the flattened disks similar to that for l-afadin, but also as numerous fine dots widely distributed in all synaptic layers of the CA1 and CA3 areas. The latter finding may correspond with the recent report by Buchert et al. (1999, J. Cell. Biol. 144:361-371), who found that s-afadin (AF-6) and/or l-afadin was localized at the postsynaptic membranes of asymmetric synaptic junctions. Our present results indicate that l- and s-afadins are differentially distributed in the hippocampus and suggest that l-afadin localized at the puncta adhaerentia-like junctions in the mossy fiber terminals may regulate the structural and functional organization of these complex synaptic structures.  相似文献   
100.
OBJECT: In this study the authors identify and investigate two new classifications of suprasellar arachnoid cysts. METHODS: The authors used computerized tomography cisternography, magnetic resonance (MR) imaging, and neuroendoscopy to investigate nine cases of suprasellar arachnoid cysts. A communicating cyst with early filling and early clearance of a radioopaque tracer was found in seven of nine cases; a communicating cyst with delayed filling and delayed clearance of the tracer was observed in one case; and a noncommunicating cyst was observed in the other. The MR findings indicated a variation in the position of the basilar artery (BA) bifurcation in relation to the ventral surface of the midbrain. A distance existed between the BA bifurcation and the ventral surface of the midbrain in a communicating cyst with early filling, whereas the BA bifurcation was posteriorly displaced in a communicating cyst with delayed filling and also in a noncommunicating cyst, leaving little space between the bifurcation and the ventral surface of the midbrain. Endoscopic observation revealed, in the case of communicating cysts with early filling and early clearance of tracer, that the BA bifurcation is located inside the cyst with no overlying membrane, whereas in a noncommunicating cyst, the BA and its branches can be observed through the transparent membrane of the lesion. CONCLUSIONS: The authors postulate two different types of suprasellar arachnoid cysts: a noncommunicating intraarachnoid cyst of the diencephalic membrane of Liliequist and a communicating cyst that is a cystic dilation of the interpeduncular cistern.  相似文献   
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