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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
961.
M S Lipsky 《American family physician》1986,34(5):173-177
Patients with chronic hiccups should be carefully examined for an underlying disorder while receiving symptomatic treatment. Treatment includes physical maneuvers, drugs such as chlorpromazine, metoclopramide, anticonvulsants or quinidine, and other, less tested modalities such as hypnosis. Only those patients with disabling hiccups that do not respond to conservative treatment should be considered for phrenic nerve surgery. 相似文献
962.
A lawsuit directed by parents at a day care program following an outbreak of infectious disease would most likely be based on the legal theory of negligence--the failure to exercise due care as required by circumstances. In the determination of liability for infectious diseases in child day care, the element of causation is most critical. Did the day care facility's actions or failure to act cause the harm? Another important question is whether an infectious disease can be occupational and under what circumstances. Although worker's compensation laws initially had no provisions for occupational disease, now all states recognize responsibility for them. Awareness of potential problems with legal liability and establishment of procedures to minimize risk are important for day care providers, public health officials, clinicians, and parents. 相似文献
963.
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965.
Reserpine enhances amphetamine stereotypies without increasing amphetamine-induced changes in striatal dialysate dopamine 总被引:4,自引:0,他引:4
Indirect evidence suggests that amphetamine (AMPH) releases dopamine (DA) from an extravesicular, cytoplasmic pool. Disruption of vesicular DA storage by reserpine has been hypothesized to increase the concentration of extravesicular DA available for release by AMPH, which is consistent with the observation that reserpine does not prevent but augments the behavioral response to AMPH. In order to more directly test this hypothesis, the in vivo microdialysis technique was used to concurrently examine the behavioral and striatal dopaminergic response to AMPH (1.25 or 2.5 mg/kg) 24 h following reserpine pretreatment (2.5 mg/kg). Reserpine decreased tissue levels of DA by approximately 90% and reduced baseline dialysate DA concentrations by approximately 80%. Reserpine augmented the behavioural effects of AMPH, particularly increasing the occurrence and intensity of stereotypies. In contrast, reserpine did not alter the amount or duration of AMPH-induced DA release. This observation confirms that DA release by AMPH does not depend on vesicular stores but is inconsistent with the hypothesis that augmentation or behaviour by reserpine results from increased striatal DA release. 相似文献
966.
Civil commitment standards and patient mix in England/Wales, Italy, and the United States 总被引:1,自引:0,他引:1
S P Segal 《The American journal of psychiatry》1989,146(2):187-193
Although England/Wales, Italy, and the United States share a common policy of deinstitutionalization, their mental health systems differ considerably. Each country's civil commitment standards define patient eligibility criteria along one of two primary dimensions--need for treatment or degree of dangerousness. These differential selection criteria result in mental health systems serving different subgroups of the total population. The criteria in England/Wales target older women; in the United States, younger men; and in Italy, a group balanced in age and sex. Implications for the current debate on civil commitment policies are considered. 相似文献
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S Shuman E M Kane S G Morham 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(24):9793-9797
Site-directed mutagenesis of the vaccinia virus gene encoding a type I DNA topoisomerase implicates Tyr-274 as the active-site residue that forms a covalent adduct with DNA during cycles of DNA-strand breakage and reunion. Replacement of Tyr-274 by phenylalanine results in loss of the ability of the enzyme to relax negatively supercoiled DNA as well as to form the covalent DNA-protein intermediate. Substitution of phenylalanine for tyrosine at nine other sites in the protein has no apparent effect on enzyme activity. Amino acid sequence alignment reveals Tyr-274 to be homologous to Tyr-727 and Tyr-771, respectively, of the type I topoisomerases from Saccharomyces cerevisiae and Saccharomyces pombe; Tyr-727 and Tyr-771 have been shown to represent the active-site tyrosines of those enzymes. Sequence comparison of the active-site regions defines a motif Ser-Lys-Xaa-Xaa-Tyr common to the viral and cellular type I topoisomerases, including the human enzyme. 相似文献