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41.
The isoleucyl-tRNA synthetase (ileS) gene was sequenced in toto from 9 and in part from 31 Staphylococcus aureus strains with various degrees of susceptibility to mupirocin. All strains for which the mupirocin MIC was greater than 8 microg/ml contained point mutations affecting the Rossman fold via Val-to-Phe changes at either residue 588 (V588F) or residue 631 (V631F). The importance of the V588F mutation was confirmed by an allele-specific PCR survey of 32 additional strains. Additional mutations of uncertain significance were found in residues clustered on the surface of the IleS protein.  相似文献   
42.
PURPOSE: This study was designed to investigate the role of nitric oxide in neurogenic relaxation of the longitudinal layer of human rectal smooth muscle. METHODS: Tissue was obtained from the mid rectum of patients undergoing anterior resection for carcinoma. Adjacent strips of longitudinal muscle were dissected and mounted in organ baths for isometric tension recording. In preliminary experiments to determine the response of strips to cholinergic, adrenergic, and potential excitatory agonists, strips were superfused with standard Krebs solution (37±0.5°C; pH, 7.4±0.05). Investigation of inhibitory, nonadrenergic noncholinergic responses required the addition of 3×10−6 M histamine to induce reproducible and stable tension for five-minute “test” periods, during which electrical field stimulation (EFS) and additional drugs were applied. In these experiments, strips were superfused with Krebs solution that contained atropine sulfate (3×10−6 M) and guanethidine (3×10−6 M). RESULTS: The response to cholinergic and adrenergic agonists was typical of nonsphincter specialized gastrointestinal smooth muscle. EFS elicited frequency-dependent, neurogenic (tetrodotoxin-sensitive) relaxations of precontracted strips, which were reduced in dose-dependent fashion by addition of-nitro-l-arginine and restored by addition of 3×10 −4 M l-arginine but not by d-arginine. Addition of exogenous nitric oxide (sodium nitroprusside) mimicked the relaxant response induced by EFS. CONCLUSION: Smooth muscle from the longitudinal layer of human rectum receives an intrinsic inhibitory innervation mediated by nitric oxide. Supported and financed by the Medical Research Council, United Kingdom. John Stebbing is in receipt of a Medical Research Council Clinical Training Fellowship. Read at the meeting of The American Society of Colon and Rectal Surgeons, Seattle, Washington, June 9 to 14, 1996.  相似文献   
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Alex  Neil 《JAMA》2004,291(24):3017
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Isolated sphenoiditis: a diagnostic problem   总被引:1,自引:0,他引:1  
A case of primary isolated sphenoiditis that developed cavernous sinus thrombosis is presented. It is difficult to diagnose and patients are often not seen initially by an ENT surgeon, making it more important for other branches of medicine to be aware of this condition. We discuss isolated sphenoiditis with particular reference to the diagnosis, management and complications of this condition.  相似文献   
47.
Objectives: To evaluate a group intervention to help individuals with psychiatric disorder stop smoking.
Method: A waitlist-treatment crossover design. Outcome measures included smoking cessation, motivation to stop, the Fagerstrom Test for Nicotine Dependence (FTND), urinary cotinine and psychiatric symptoms on the General Health Questionnaire.
Results: 38 subjects participated, of whom 19 completed the waitlist and intervention phases. There were no significant differences between subjects and dropouts. During the waitlist period there were no significant changes in tobacco use. At the end of the intervention, almost a quarter had stopped smoking, ( z = -2.24, p =0.02). Subjects also showed significant improvements on state of change, FTND score and urinary cotinine levels. These improvements were maintained at three-month follow-up (n=10). Psychiatric morbidity showed no change.
Conclusions: It is possible to reduce smoking in individuals with psychiatric disorder.
Implications: Larger randomised controlled trials are indicated to determine the relative contributions of nicotine replacement, bupropion and group interventions to smoking cessation in this population.  相似文献   
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Background and Purpose:   

Management of rib fractures constitutes a major part of the trauma workload of any unit. Rib fractures result in disrupted chest wall mechanics and ventilatory insufficiency. The ability of a lung injury scoring system to predict the degree of respiratory dysfunction after rib fractures was evaluated.  相似文献   
50.
With the exception of post-exposure prophylaxis for reported rape, no preventive strategy addresses the choice disabled – those who might like to benefit from AIDS prevention but who are unable to do so because they do not have the power to make and to act on prevention decisions. In southern African countries, where one in every three has been forced to have sex by the age of 18 years, a very large proportion of the population is choice disabled. This group is at higher risk of HIV infection and unable to respond to AIDS prevention programmes; they represent a reservoir of infection. Reduction of sexual violence would probably decrease HIV transmission directly, but also indirectly as more people can respond to existing AIDS prevention programmes.  相似文献   
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