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R Borland  J P Pierce  D M Burns  E Gilpin  M Johnson  D Bal 《JAMA》1992,268(6):749-752
OBJECTIVE--To determine the extent of exposure of nonsmoking indoor workers to environmental tobacco smoke (ETS) according to type of work-site smoking policy, work area, workplace size, and demographic characteristics. DESIGN AND PARTICIPANTS--Participants included 7162 adult, nonsmoking, indoor workers who were interviewed as part of the 1990 California Tobacco Survey. Respondents were asked whether anyone had smoked in their work area within the past 2 weeks. RESULTS--An estimated 2.2 million California nonsmokers were exposed to tobacco smoke at indoor work sites in 1990. Nonsmoker exposure to ETS was 9.3% for those working in a smoke-free worksite, 23.2% for those working where there was only a work-area restriction, 46.7% for those working where there was a policy that did not include the work area, and 51.4% for those working where there was no work-site smoking policy. After adjustment for type of work area (eg, office, open area), workplace size, and demographic factors, it was determined that nonsmokers working where there was only a work-area ban were 2.8 times more likely to be exposed to ETS than those working in a smoke-free work site. In workplaces with no policy or a policy not covering the work area, nonsmokers were over eight times more likely to be exposed to ETS than those who worked in a smoke-free work site. Nonsmokers who were 18 to 24 years of age, male, or Hispanic, and those with less than a high school education had more exposure to ETS. CONCLUSION--These results indicate that adequate protection of nonsmokers from ETS exposure requires a smoke-free work site.  相似文献   
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The records of 1018 patients with low back pain in a tertiary spine referral practice were reviewed. One hundred thirty-nine out of 1018 (13.6%) underwent technetium-99m planar bone scanning as part of their investigation. Seventy-three out of 139 scans (52%) showed increased uptake in some area, but only 27 out of 139 (19.4%) showed increased uptake specifically in the low back. Scans consistently yielded no findings with reference to the back when the prescan diagnosis was spinal stenosis, lumbar pain syndrome, herniated nucleus pulposus, or postlaminectomy syndrome. Some scans gave positive findings in patients with a diagnosis of degenerative disc disease, pseudarthrosis, spondylolisthesis, fracture, infection, metabolic disorder, or tumor. Positive scans were generally obtained early after presentation (within 3 months) and negative scans obtained later (after 6 months), suggesting that clinical suspicion is still the main indication for early scanning. Planar bone scanning was helpful in both diagnosis and therapeutic decisionmaking in many conditions.  相似文献   
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Summary Several components of a system for structure generation are now well developed. HIPPO is a program that characterises a receptor binding site for potential target sites within the cavity that can be used in de novo design. The target sites include simple and complex hydrogen bonds, covalent bonds and bonds to metal ions. The SPROUT program for structure generation consists of two main components: the first is skeleton generation, followed by atom substitution to convert the solution skeletons to molecules. A new method of skeleton generation is presented here, where part skeletons are grown outwards from each target site. The part skeletons are then connected together to form solution skeletons. Finally the CAESA program is described, that ranks the output from SPROUT according to ease of synthesis.  相似文献   
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This study investigated the effects of neurokinin A (NKA) on cholinergic neural responses in human bronchus. NKA (0.1 nM) did not alter the contractile response to submaximal electrical field stimulation. However, K+ channel blockade with 4-aminopyridine (4-AP) (0.1 mM) potentiated the response to electrical field stimulation (to 182 ± 25% of control, n = 4, P < 0.05) and subsequent addition of NKA in the presence of 4-AP produced further potentiation (to 123 ± 6% of the response to 4-AP n = 4, P < 0.05). Neither 4-AP (0.01 or 0.1 mM) nor NKA in the presence of 4-AP potentiated the actions of exogenous acetylcholine but in these experiments 4-AP itself produced a marked direct contractile response. Thus NKA in the presence of K+ channel blockade potentiates cholinergic neural response in human bronchus and this occurs at a prejunctional site.  相似文献   
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Increasing reports of vancomycin resistance have raised concerns about the future effectiveness of this drug in treatment of critically ill patients with gram-positive infections. Due to these concerns the Centers for Disease Control and Prevention (CDC) recently published criteria that delineate the prudent use of vancomycin. Using these criteria, we attempted to determine the appropriateness of vancomycin prescribing patterns at our institution. A retrospective chart review was performed for 135 hospitalized patients treated between May 1993 and April 1994. Inappropriate empiric vancomycin use was documented in 81 (60%) of these patients. When culture results were available, 28 (21%) patients inappropriately received the drug. Results of this study are similar to those of other studies of vancomycin use in hospitals based on non-CDC criteria. If CDC criteria are to have a positive impact on physicians' vancomycin prescribing patterns, significant educational efforts will be required.  相似文献   
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