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91.
92.
Darier's disease. Treatment with topical vitamin A acid 总被引:2,自引:0,他引:2
93.
The application, in the bathing medium, of ACh (10−5 M) to the extensor tibiae nerve-muscle preparation of the locust caused a dosedependent increase in both the spontaneous and evoked release of transmitter and also modified the statistical characteristics of the spontaneous release process. ACh had no postsynaptic action. The effects of ACh on spontaneous transmitter release were dependent on extracellular calcium concentration and could be mimicked by carbachol, nicotine and acetyl-β-methylcholine and antagonised by D-tubocurarine and decamethonium. The results suggest the presence of cholinergic receptors on the nerve terminal of the locust neuromuscular junction. 相似文献
94.
V A Levin P S Vestnys M S Edwards W M Wara D Fulton G Barger M Seager C B Wilson 《Cancer》1983,51(8):1364-1370
Thirty-six patients with recurrent medulloblastoma were treated with various combination chemotherapy protocols after initial treatment (usually irradiation) failed. Use of systemic chemotherapy was limited by depressed bone marrow reserves secondary to previous craniospinal irradiation. Intraventricular and intrathecal therapies included cytosine arabinoside (Ara-C), methotrexate, and thio-tepa given as single agents. Major systemic agents used alone or in combination included CCNU, procarbazine, vincristine, and the hexitol epoxides. Patients were reirradiated with or without misonidazole when there was definite tumor progression after all other therapies failed and/or because myelosuppression was so severe that further chemotherapy was not possible. Sequential systemic or intrathecal chemotherapy and reirradiation produced median survivals of two years and 25% quartile survivals of 2.9 years. The prognosis for patients harboring recurrent medulloblastoma has improved considerably over the years because of the therapeutic approaches reported here. 相似文献
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Orbital cellulitis and abscess are known complications of ethmoiditis in children, but they are very rare in the newborn. The authors report a case of orbital abscess caused by methicillin-resistant Staphylococcus aureus (MRSA) in a four-week-old neonate born four weeks prematurely. 相似文献
97.
Chronic alcohol exposure reduces hippocampal neurogenesis and dendritic growth of newborn neurons 总被引:7,自引:0,他引:7
Hippocampal neurogenesis is known as the formation of new neurons from the proliferating neural progenitor cells (NPC) at the dentate gyrus. Cell proliferation, survival, differentiation and maturation are critical stages leading to the generation of healthy neurons. As all of these stages can be influenced by alcohol exposure, we studied the effects of chronic alcohol on each process by immunocytochemistry for stage-specific antigens and prelabelling newborn cells with bromodeoxyuridine (BrdU). Rats were administered alcohol liquid diet or control diet for one, two or four weeks. We found that cell proliferation was inhibited as proliferating cell nuclear antigen (PCNA) expression was reduced by approximately 50% in alcohol-treated animals at all time points. Doublecortin (DCX), a microtubule protein expressed early in differentiating neurons, was progressively decreased over the duration of exposure and significantly reduced after two and four weeks of drinking. Morphological analyses of DCX-positive cells revealed that four weeks of alcohol treatment reduced the size of the dendritic tree including the total length of apical dendrites, number of nodes and endings. Furthermore, BrdU labelling demonstrated a dramatic decrease in cell survival after four weeks of drinking, while cell death was increased by such treatment. Confocal analysis indicated that over 80% of BrdU+ cells colabelled with NeuN suggesting that alcohol reduced neurogenesis. In conclusion, chronic alcohol exposure disrupts neurogenesis by decreasing NPC proliferation, inhibiting cell survival and altering morphological maturation of newborn neurons. These data implicate impaired hippocampal neurogenesis with the cognitive and affective dysfunction associated with chronic alcoholism. 相似文献
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An ethics framework for the use of the Internet for nursing education, consultation, research, and practice is proposed. The proposed framework, discussed in terms of structure, process, and outcome, would guide policy for confidentiality, privacy issues, professionalism, ownership of intellectual property, accountability, and control of access. A goal would be to encourage creative problem solving without constant reference to authority. 相似文献