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11.
We compared smoking prevalence in 217 patients with panic disorder with that in 217 age- and sex-matched control subjects who were obtained by telephone survey from the same neighborhoods. Data were obtained for current smoking habits and smoking status at either the onset of illness (patients) or 10 years previously (control subjects). Patients had been ill for 10.6 (SD = 10.0) years. Female patients with panic disorder had a significantly higher smoking prevalence at the onset of their illness than did control subjects 10 years previously (54% vs. 35%). The current smoking prevalence for female patients was also significantly higher than that of control subjects (40% vs. 25%). Male smoking rates did not differ between patients and control subjects. Caffeine use did not appear to explain these findings. These data suggest a link between smoking behavior and panic disorder in women.  相似文献   
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A retrospective study was performed to compare intravenous lorazepam and intravenous diazepam in the treatment of status epilepticus. Forty-five episodes of status epilepticus in children between the ages of 2 weeks and 18 years were reviewed. Lorazepam and diazepam proved similar in efficacy of seizure control and incidence of adverse effects. The dose of lorazepam required to control status epilepticus ranged from 0.03 to 0.22 mg/kg with a mean of 0.11 mg/kg (S.D. = 0.05 mg/kg). Among children treated with lorazepam, only children younger than 2 years of age had respiratory depression which required intubation.  相似文献   
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Platelet or whole blood serotonin content did not differ significantly in patients with major depression compared to healthy controls, but within the patient group, platelet serotonin levels correlated negatively with severity of depression (r = -0.49, p = 0.007). Levels were 39% lower in patients who had made a suicide attempt compared to nonattempter patients (47.2 +/- 27.3 versus 77.6 +/- 41.7 ng/10(8) platelets, p = 0.04). Conversely, comorbid borderline personality disorder (85.3 +/- 41.5 ng/10(8) platelets) was associated with 31% greater platelet serotonin content than nonborderline patients (58.9 +/- 31.1 ng/10(8) platelets) and 27% greater than healthy controls (62.4 +/- 19.8 ng/10(8) platelets). A pronounced seasonal variation in whole blood and platelet serotonin content was found in both patients and controls, largely due to lower levels in summer. Excluding cases tested in the summer abolished the statistically significant differences in patients with and without comorbid borderline personality disorder (BPD). Nevertheless, BPD attempters had lower serotonin levels than BPD nonattempters but higher serotonin levels than non-BPD attempters. Current hostility and a life-time history of aggression were positively correlated with platelet serotonin content (r = 0.44, p = 0.04 and r = 0.41, p = 0.06). This study provides evidence for an association between lower platelet serotonin content and depression and suicidal behavior, and association of higher platelet serotonin content and comorbid borderline personality disorder and behavior traits such as aggressivity.  相似文献   
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Recent serologic, immunoprotection, and pathogenesis studies identified the Lig proteins as key virulence determinants in interactions of leptospiral pathogens with the mammalian host. We examined the sequence variation and recombination patterns of ligA, ligB, and ligC among 10 pathogenic strains from five Leptospira species. All strains were found to have intact ligB genes and genetic drift accounting for most of the ligB genetic diversity observed. The ligA gene was found exclusively in L. interrogans and L. kirschneri strains, and was created from ligB by a two-step partial gene duplication process. The aminoterminal domain of LigB and the LigA paralog were essentially identical (98.5 ± 0.8% mean identity) in strains with both genes. Like ligB, ligC gene variation also followed phylogenetic patterns, suggesting an early gene duplication event. However, ligC is a pseudogene in several strains, suggesting that LigC is not essential for virulence. Two ligB genes and one ligC gene had mosaic compositions and evidence for recombination events between related Leptospira species was also found for some ligA genes. In conclusion, the results presented here indicate that Lig diversity has important ramifications for the selection of Lig polypeptides for use in diagnosis and as vaccine candidates. This sequence information will aid the identification of highly conserved regions within the Lig proteins and improve upon the performance characteristics of the Lig proteins in diagnostic assays and in subunit vaccine formulations with the potential to confer heterologous protection.  相似文献   
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Survival of random skin flap distal end depends on hemodynamic, cellular, and coagulation mechanisms. This study was designed to evaluate whether administration of ciprostene, a stable prostaglandin I2 analogue, and indomethacin, a cyclooxygenase-hydroperoxydase enzyme inhibitor, would improve the survival rate of random skin flaps. Forty-five male rats were divided into nine groups and injected with sesame oil (control), ciprostene (20 micrograms/kg/day), and/or indomethacin (2 mg/kg/day). Injections were done before (pretreatment for 4 days), after (posttreatment for 6 days), and before/after (pre/posttreatment for 4 and 6 days, respectively) the elevation of random dorsal skin flaps. In the pretreatment and pre/posttreatment studies, the flap survival rate of all drug-injected groups was significantly higher than that of the control group (p less than 0.02). In addition administration of ciprostene alone yielded a trend of better flap survival rate, which, however, was not statistically significant (p less than 0.12). Of interest in the posttreatment study, only the simultaneous administration of ciprostene and indomethacin significantly increased skin flap viability compared with the other groups (p less than 0.02). Therefore, the results demonstrated that administration of ciprostene and indomethacin either alone or together partially reversed the pathophysiological mechanisms that cause necrosis of random skin flap distal end. These pharmacological changes significantly improved random skin flap survival rate.  相似文献   
19.
The mesoaccumbens dopamine system has been hypothesized to be a common neural substrate mediating the actions of various drugs of abuse, including ethanol. However, the involvement of the mesopallidal dopamine system has received very little attention. The present study examined the effects of intraperitoneal (IP) ethanol administration on the extracellular levels of dopamine in the ventral pallidum (VP) and globus pallidus (GP) of Wistar rats. Rats were bilaterally implanted with microdialysis probes aimed at the VP and GP or nucleus accumbens (NAc) and dorsal striatum (dSTR). During microdialysis testing, rats with probes located in the VP and GP were injected IP with sterile saline or 15% (v/v) ethanol in saline at doses of 0.75, 1.5, or 2.25 g/kg. Rats with NAc and dSTR probes were injected with saline or 2.25 g/kg ethanol. The IP administration of 1.5 and 2.25 g/kg ethanol significantly (p <0.05) elevated the extracellular levels of dopamine in the VP (maximal increase: 136 and 182% of baseline, respectively) but not in the GP. No effects on extracellular dopamine levels were observed following the IP injections of 0.75 g/kg ethanol or saline. The IP administration of 2.25 g/kg ethanol significantly (p <0.05) elevated the extracellular levels of dopamine in the NAc (maximal increase: 198% of baseline) and dSTR (maximal increase: 155% of baseline). Analysis of the effects of 2.25 g/kg ethanol on dopamine release revealed greater increases in the VP, NAc, and dSTR compared to the GP. The data suggest that the mesopallidal, mesoaccumbens, and nigrostriatal dopamine systems are more sensitive to the effects of ethanol than the nigropallidal dopamine system.  相似文献   
20.
Glutaurine (gamma-L-glutamyl taurine), a proposed hormone isolated from parathyroid gland oxyphil cells, was examined for its effect on circulating thyroid hormones in the rat. In acute experiments performed over a 24 hr. period, glutaurine depressed plasma triiodothyronine (T3) levels in a dose-dependent manner; however, thyroxine (T4) levels were not affected significantly. In chronic experiments performed over a 2 wk. period, glutaurine significantly increased T3 levels, but, as with acute studies, the effect of T4 levels was not significantly altered. Following acute glutaurine administration, TSH levels were elevated above control. The increased T3 observed following chronic glutaurine administration may be due to a secondary increase in TSH levels. These data support the hypothesis that glutaurine aids in peripheral thyroid hormonal regulation. Observed differences between acute and chronic glutaurine action are though to result from the effect of glutaurine on the negative feedback inhibiting action of TSH.  相似文献   
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