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991.
Summary Acute exposure of mice to hypobaric hypoxia, or reduced oxygen at normal pressure, markedly potentiated barbiturate-induced hypnosis. The mice showed lower body concentration of pentobarbital on awakening and reduced rate of pentobarbital disappearance from the body during exposure to the hypoxic environment. These data suggest that acute exposure to hypoxia depresses in vivo metabolism of pentobarbital and enhances CNS sensitivity to the barbiturates.  相似文献   
992.
Outpatient termination of pregnancy   总被引:1,自引:0,他引:1  
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993.
Summary The effect of passage of time on the power of muscles of the lower limbs affected by polio was noted. The patterns of muscle power recorded in the 1–6-month, 6–12-month and 12–24 month periods after the onset were compared. An explanation has been sought for the variation in percentage of involvement of the muscles in the three intervals. The percentage of totally paralysed muscles keeps on rising with the passage of time. The tibialis anterior and quadriceps were the most common totally paralysed muscles. The maximum incidence of variation in the muscle power was noticed in these with negligible or severe paresis. Therefore, emphasis should be placed on these while giving physical therapy. The muscles around the hip (except rotators), invertors of the foot and extensors of the toes, show more frequent variations in the muscle power as compared to others with the passage of time if left untreated. From the Physical Medicine and Rehabilitation Unit, All India Institute of Medical Sciences, New Delhi 16.  相似文献   
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997.
Driver fatigue: electroencephalography and psychological assessment   总被引:9,自引:0,他引:9  
Lal SK  Craig A 《Psychophysiology》2002,39(3):313-321
Fatigue has major implications for transportation system safety; therefore, investigating the psychophysiological links to fatigue could enhance our understanding and management of fatigue in the transport industry. This study examined the psychophysiological changes that occurred during a driver simulator task in 35 randomly selected subjects. Results showed that significant electroencephalographic changes occur during fatigue. Delta and theta activity were found to increase significantly during fatigue. Heart rate was significantly lower after the driving task. Blink rate also changed during the fatigue task. Increased trait anxiety, tension-anxiety, fatigue-inertia and reduced vigor-activity were shown to be associated with neurophysiological indicators of fatigue such as increased delta and theta activity. The results are discussed in light of directions for future studies and for the development of a fatigue countermeasure device.  相似文献   
998.
OBJECTIVE: To evaluate compliance with a legislative ban on smoking inside restaurants by comparing smoking in Sydney restaurants (where it is legally banned) with smoking in Melbourne restaurants (not subject to a legal ban). DESIGN AND PARTICIPANTS: Unobtrusive observational study of restaurant patrons, and interviews with restaurant staff, carried out by 159 volunteers. SETTING: 78 Sydney restaurants with smoke-free indoor environments (as required by legislation) and 81 Melbourne restaurants not subject to legislation preventing smoking. The study took place from 20-31 October 2000. INTERVENTION: Legislation to ban smoking in indoor areas of restaurants was introduced in New South Wales in September 2000 (about six weeks before our study). OUTCOMES: Observed incidents of smoking inside restaurants; staff attitudes to the ban; customer satisfaction as indicated by comments to staff; staff perceptions of restaurant patronage. RESULTS: No restaurant patrons were seen smoking in 78 Sydney restaurants during 156 hours of observation of 2,646 diners, compared with 176 smokers among 3,014 Melbourne diners over 154 hours of observation. Thirty-one per cent (24/78) of Sydney restaurants had experienced smokers attempting to smoke indoors after the legislation was introduced; 6% (5/78) reported instances of smokers refusing to stop smoking when asked; 79% (62/78) of restaurants had received favourable comments from patrons about the smoke-free law; 81% (63/78) of restaurant staff interviewed either supported or strongly supported the law. Since introduction of the legislation, 76% of restaurants reported normal trade, 14% increased trade, and 9% reduced trade. CONCLUSIONS: Smoke-free restaurants do not require "smoking police" to enforce bans, present few ongoing difficulties for staff, attract many more favourable than unfavourable comments from patrons, and do not adversely affect trade.  相似文献   
999.
Centchroman (Ormeloxifene), a non-steroidal oral contraceptive, is used at a dose of 30 mg once a week. To prevent failures in the beginning of the therapy, it is recommended that a dose of 30 mg twice a week for 12 weeks be administered to build up adequate blood levels. The present study was undertaken to simplify the dosing schedule without sacrificing the purpose of twice a week dosing regimen, using modeling and measurement approaches. The drug was given to 60 female volunteers who were divided into seven groups: group I, 30 mg weekly; group II, 30 mg twice a week; group III, 30 mg twice a week for 12 weeks followed by 30 mg weekly; group IV, 30 mg twice a week for 6 weeks followed by 30 mg weekly; group V, 60 mg weekly; and groups VI and VII, single 60 mg loading dose followed by 30 mg weekly doses. The blood samples were collected and analyzed by HPLC. In group I, mean trough concentrations of centchroman and its active metabolite, 7-desmethyl centchroman, were comparable to the steady-state trough concentrations in groups III, IV, VI, and VII. The metabolite to parent drug ratio remained constant in all the groups. The pharmacokinetic parameters in group VII were comparable to those reported after a single 30 mg dose. Dosage regimen VI was more convenient and provided better pregnancy protection (Pearl index 1.18; unpublished report) than regimen III, which is currently on the market and, thus, could be effectively used for contraception.  相似文献   
1000.
Postcoital vaginal rupture or tear is a well-known entity to the gynecologist, albeit unusual; however, such cases are rarely encountered by the general surgeon. The index case is reported to highlight the rare situation wherein a middle-aged woman underwent laparotomy for a suspected small bowel perforation, which revealed a vaginal tear as the cause of pneumoperitoneum. This case emphasizes the importance of taking a gynecological history and performing a gynecological examination when the clinical diagnosis is uncertain. Received: December 27, 1999 / Accepted: September 26, 2000  相似文献   
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