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Participants from the DSM-IV field trial for OCD (N = 381) were divided into two groups based on the SCID interview: those who met current criteria for obsessive-compulsive disorder (OCD) but not generalized anxiety disorder (GAD) and those who met current diagnostic criteria for both. The groups were compared on their severity of obsessive and compulsive symptoms, as well as on the percent of individuals who reported excessive worry concerning everyday issues (e.g. health, finances). The comorbidity rate was 20%. While the presence of GAD did not elevate OCD symptoms per se, it was associated with more pathological responsibility and indecisiveness. Excessive worries were significantly more common in those with comorbid OCD and GAD. The relationship between obsessions and worries is discussed.  相似文献   
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The purpose of this study was to determine whether short-term tolerance develops to GABA-agonist-induced changes in saccadic eye movements (SEMs), and whether the time course for GABA-agonist induced onset and offset of impairment is similar for SEMs and for psychomotor function. An additional goal was to determine whether there are differences in sensitivity between SEMs and psychomotor function. Six healthy volunteers participated in this balanced double-blind, three-way crossover, single-dose study of placebo and two different dosage forms of the GABA-agonist alprazolam: a rapidly absorbed oral 1.5-mg compressed tablet (CT) and a 3.0-mg sustained release (SR) tablet. Treatments were separated by a 7-day washout period. Peak concentrations did not differ between CT and SR treatments, although area under the concentration-time curve (AUC) of alprazolam was greater after administration of SR than after CT, because plateau concentrations were attained after SR. Both SEM and psychomotor tests showed time-dependent responses consistent with the development of tolerance. SEMs discriminated the differences in rate of drug input of the CT and SR formulations, with impairment evident at low concentrations during absorption. SEM impairment also persisted longer than did psychomotor impairment. Peak saccade velocity is a more sensitive indicator of pharmacologic effects mediated by the GABA-benzodiazepine receptor complex than are psychomotor responses. This is probably the result of the very high GABA dependency of SEMs, along with their limited sensitivity to motivation.  相似文献   
95.
Nonabsorbable barriers are considered the material by which all other barriers are judged. They have a well-established record of safety and efficacy. They are not a panacea, however. Practitioners must take special care when selecting both patients and surgical sites for GTR. Extensive experience, superior surgical ability, and meticulous attention to detail are also required if one is to achieve predictably favorable results.  相似文献   
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OBJECTIVES: Public policy has treated drinking and boating as though it were analogous to drinking and driving. Accordingly, recent Federal and state laws to prevent drinking and boating have focused solely on alcohol use by the boat operator. This study was designed to determine boaters' knowledge about the epidemiology of boating fatalities and how boaters perceive the risks of drinking and boating. METHODS: In the summer of 1995, the authors conducted a survey by mail of a random sample of 600 owners of boats registered in Massachusetts. RESULTS: Survey results indicated that boaters believe passengers can safely drink more than operators. Respondents also thought that people on boats at rest can safely drink more than people on boats underway. CONCLUSIONS: The results of this study could be helpful in designing future boating safety campaigns by identifying gaps in knowledge about about the risks of drinking and boating for both operators and passengers.  相似文献   
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OBJECTIVES: To document the prevalence of work related ocular (eyeWRI) and nasal (noseWRI) irritation in workers in spinning mills of cotton and synthetic textile fibres and to relate the prevalence of symptoms to atopy, byssinotic symptoms, work history, and measured dust concentrations in the personal breathing zone and work area. METHODS: A cross sectional study of 1048 cotton workers and 404 synthetic fibre workers was performed. A respiratory questionnaire was given to 1452 workers (95% of the total available population). Atopy was judged by skin prick tests to three common allergens. Work area cotton dust sampling (WAdust) was carried out according to EH25 guidelines in nine of the 11 spinning mills included in the study. Personal breathing zone dust concentrations were assessed with the IOM sampler to derive total dust exposure (PTdust) and a concentration calculated after the removal of fly (Pless). RESULTS: 3.7% of all operatives complained of symptoms of byssinosis, 253 (17.5%) complained of eyeWRI and 165 (11%) of noseWRI. These symptoms did not relate to atopy or byssinosis, or correlate univariately with any measure of cotton dust exposure (noseWRI v WAdust r = 0.153, PTdust r = 0.118, eyeWRI v WAdust r = 0.029, PTdust r = 0.052). Both of these symptoms on logistic regression analysis were related to being of white origin (P < 0.001), female sex (P < 0.001), and younger age (P < 0.001). With regression analysis, there was a negative relation between dust concentration and prevalence of symptoms. CONCLUSION: Work related ocular and nasal irritation are the most common symptoms complained of by cotton textile workers. There was no relation between these symptoms and atopy, byssinosis, or dust concentration. It is likely that they relate to as yet unidentified agents unrelated to concentration of cotton dust.  相似文献   
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Although the therapeutic actions of glucocorticoids are largely attributed to their anti-inflammatory and immunosuppressive effects, they have been implicated in enhancing tissue and cellular protection. In this study, we demonstrate that dexamethasone significantly enhances viability of IEC-18 rat small intestinal cells against oxidant-induced stress in a dose-dependent fashion. This protective action is mediated by induction of hsp72, the major inducible heat shock protein in intestinal epithelial cells. Dexamethasone stimulates a time- and dose-dependent response in hsp72 protein expression that parallels its effects on cell viability. Furthermore, the induction of hsp72 is tissue dependent, as nonintestinal epithelioid HeLa cells show differential induction of hsp72 expression in response to the same dexamethasone treatment. Antisense hsp72 cDNA transfection of IEC-18 cells abolishes the dexamethasone-induced hsp72 response, without significantly affecting constitutive expression of its homologue, hsc73. Dexamethasone treatment also significantly induces hsp72 protein expression in rat intestinal mucosal cells in vivo. These data demonstrate that glucocorticoids protect intestinal epithelial cells against oxidant-induced stress by inducing hsp72.  相似文献   
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