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961.
A pineal hormone melatonin (1 mg/kg, 24 days) facilitated the formation of tolerance to haloperidol and eliminated the changes produced by it in the processes of microsomal oxidation in rats. Pinealectomy yielded the opposite result. After pinealectomy the normalizing effect of the hormone on the condition of the liver monoxygenase system and the effects of haloperidol weakened. 相似文献
962.
Interaction of midazolam and morphine in the spinal cord of the rat 总被引:11,自引:1,他引:10
The antinociceptive properties, as measured by the tail-flick and hot-plate tests, and the motor effects of an intrathecally-administered benzodiazepine agonist midazolam, alone, and in combination with morphine, was examined in rats. Midazolam alone produced a weak but dose-dependent (20-60 micrograms) antinociceptive effect in addition to a clear motor dysfunction at larger doses (60-100 micrograms). An inactive dose of intrathecally-administered midazolam (20 micrograms) produced a leftward shift in the dose-response curve for intrathecally administered morphine, in the thermal antinociceptive tests. This supra-additive effect was antagonized by naloxone (1 mg/kg). The data suggest a synergistic interaction between mu- and GABAA-receptors in the spinal processing of thermally-evoked pain. 相似文献
963.
964.
Binding profile of SM-9018, a novel antipsychotic candidate 总被引:3,自引:0,他引:3
T Kato A Hirose Y Ohno H Shimizu H Tanaka M Nakamura 《Japanese journal of pharmacology》1990,54(4):478-481
The present study employed various receptor-binding assays to clarify the biochemical characteristics of SM-9018. SM-9018 possessed very high affinity for 5-HT2, D2 and 5-HT1A receptors (Ki = 0.61, 1.4 and 2.9 nM, respectively), and it had moderate affinity for alpha 1 and D1 receptors (Ki = 17 and 41 nM, respectively). However, SM-9018 had only negligible affinity for alpha 2, opiate, glutamate, phencyclidine, benzodiazepine and GABAA receptors. These results suggest that SM-9018 may be a novel antipsychotic agent with binding affinity for 5-HT2 and 5-HT1A receptors. 相似文献
965.
We examined the involvement of GABAergic neuronal systems in benzodiazepine-induced passive avoidance deficit. Chlordiazepoxide impaired the passive avoidance response dose dependently when it was given prior to training. Post-training administration of muscimol improved the performance of chlordiazepoxide-pretreated mice. The effects of muscimol were antagonized completely by the GABAA antagonist, bicuculline, and the muscarinic acetylcholine receptor antagonist, scopolamine, but not by the benzodiazepine receptor antagonist, flumazenil, when the latter was administered immediately after training. It appears from these results that the GABAergic neuronal system plays an important role in the benzodiazepine-induced passive avoidance deficit by interacting with the cholinergic neuronal system. 相似文献
966.
T Bencheikh 《World health forum》1988,9(4):607-610
Morocco's severe financial problems have threatened its health-for-all goals. Restrictions have affected the recruitment and replacement of health personnel, the purchase and maintenance of equipment and buildings, hospital catering services and drug procurement. Several methods have been used to try and ease this crisis, rationalization and better deployment of resources, mobilization of national resources, and mobilization of external resources. In attaining the 1st, restrictions on the credits allocated to the Ministry of Public health have forced it to work out better ways of using its resources. These have included plans for better administrative and financial management of hospitals, improvements in drug procurement and distribution, new methods of personnel management, and efforts at improving information facilities and analytical capabilities at the central and local levels. To mobilize internal resources several steps were taken. These included revising too-low hospital charges, and charging people with social security coverage or those able to pay directly, raising funds through private charities, and the establishment of alternative, less expensive types of health centers. Morocco's continued need for funds to achieve health-for-all goals led it to also receive substantial assistance from international agencies (including the World Bank, UNICEF, UNFPA, and USAID) and friendly countries. External assistance cannot provide definitive solutions however, because of 1) the use of foreign experts and the payment of salaries abroad, 2) the purchase of products from the countries providing assistance, and 3) the unpredictability of external support and the danger programs may have to be abandoned. In times of financial crisis it is necessary to continue to budget adequately in order to reach health objectives. 相似文献
967.
Volunteers trained by a social worker did a telephone screening of 716 elderly persons waiting for elective surgery to determine in advance of admission their need for social services. On the basis of their findings patients were given a risk rating by a social worker. While the survey was experienced positively by patients, volunteers, and social workers, the results do not establish its value in terms of shortened length of stay. Aging females living alone required the greatest amount of social work and had the longest length of stay. This group requires further study, along with the connection between intensity of illness with social problem vulnerability. The study raises other important questions critical to programming for an increasingly older population. 相似文献
968.
Use of plant- and period-specific job-exposure matrices in studies on occupational cancer 总被引:4,自引:0,他引:4
Job-exposure matrices were constructed and applied in the estimation of past exposures in a case-referent study nested within a cohort of Finnish woodworkers. The objective was to avoid bias in the risk estimates because of a misclassification of exposures. The matrices were constructed separately for each plant under study and each calendar year of follow-up. The level of exposure was incorporated in the matrices, since rather comprehensive data on exposures were available. The individual work histories were converted to exposure histories by a computer program which calculated several exposure indicators (eg, level and dose, with and without allowance for a latency period). The comparison between several indicators was thought to provide additional information for the final evaluation of results. The use of the plant- and period-specific job exposure matrices may be considered in cohort and nested case-referent studies on occupational hazards as an alternative to other procedures used in the estimation of exposures. Specific matrices may find broader applicability along with the increasing availability of detailed hygienic data. 相似文献
969.
Risk for reduced sperm quality among metal workers, with special reference to welders 总被引:7,自引:0,他引:7
J T Mortensen 《Scandinavian journal of work, environment & health》1988,14(1):27-30
The purpose of this study was to investigate whether men employed in the metal industry have sperm of poorer quality than men in other types of work. A postal questionnaire was sent to men employed in the metal industry, certain other types of nonmetal industries, and other types of employment in which the factors suspected to influence sperm quality were not present. By means of this questionnaire survey, it was hoped to define the possible influences of the work environment on sperm quality. Out of the total of 3,119 men included in the investigation, 2,517 (81%) filled out the questionnaire satisfactorily. Semen analysis was performed for all 3,119 men. There was a greater risk for poor sperm quality among welders than among men not employed in welding. The risk for poor sperm quality was increased for those welders who worked with stainless steel. Welding in general, and specifically with stainless steel, is connected with a risk of reduced sperm quality. 相似文献
970.
A 63-year-old man developed bilateral conjunctival injection and irritation followed by periocular discomfort and diplopia. Within weeks left proptosis and intermittent fever were noted. Orbital CT scan showed bilateral nodular enlargement of multiple extraocular muscles. Fine needle aspiration biopsy of the extraocular muscles revealed neoplastic cells compatible with a renal cell carcinoma. The bilateral extraocular muscle metastases were the initial manifestations of the underlying malignancy. 相似文献