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Vagus Nerve Stimulation Induces a Sustained Anticonvulsant Effect 总被引:17,自引:11,他引:6
Summary: Purpose: Stimulation of the vagus nerve can effectively abort several types of experimentally induced seizures in animals when administered near the time of seizure onset. Indirect evidence from human trials and animal studies suggests that the anticonvulsant effects of vagus nerve stimulation (VNS) extend beyond the duration of stimulation. We used the pentylenetetrazol model to determine whether VNS exerts a persistent anticonvulsant effect.
Methods: VNS (1 mA, 30 Hz, 500 μs pulse width) was administered continuously for 0, 1, or 60 min, or intermittently (30 s on, 5 min off) for 60 min, to awake and freely moving animals. After the end of stimulation, pentylenetetrazol (50 mg/kg i.p.) was administered to induce seizures. Time-course studies were also performed, consisting of 60 min of VNS followed by pentylenetetrazol injection after 0, 3-, 5-, and 10-min intervals.
Results: The greatest anticonvulsant effect occurred after 60 min of continuous VNS, which prevented convulsions in four of 12 rats and reduced significantly seizure duration, the total number of seizures, and number of tonic seizures. Intermittent VNS was less effective than continuous stimulation for 60 min, but more effective than that for 1 min. The anticonvulsant effect declined in a time-dependent fashion after discontinuation of VNS, with return to nonstimulated control values by 10 min.
Conclusions: The results of this study verify a persistent VNS-induced anticonvulsant effect and indicate that its efficacy is dependent on the cumulative stimulus duration. 相似文献
Methods: VNS (1 mA, 30 Hz, 500 μs pulse width) was administered continuously for 0, 1, or 60 min, or intermittently (30 s on, 5 min off) for 60 min, to awake and freely moving animals. After the end of stimulation, pentylenetetrazol (50 mg/kg i.p.) was administered to induce seizures. Time-course studies were also performed, consisting of 60 min of VNS followed by pentylenetetrazol injection after 0, 3-, 5-, and 10-min intervals.
Results: The greatest anticonvulsant effect occurred after 60 min of continuous VNS, which prevented convulsions in four of 12 rats and reduced significantly seizure duration, the total number of seizures, and number of tonic seizures. Intermittent VNS was less effective than continuous stimulation for 60 min, but more effective than that for 1 min. The anticonvulsant effect declined in a time-dependent fashion after discontinuation of VNS, with return to nonstimulated control values by 10 min.
Conclusions: The results of this study verify a persistent VNS-induced anticonvulsant effect and indicate that its efficacy is dependent on the cumulative stimulus duration. 相似文献
34.
H(1)-histamine receptor affinity predicts short-term weight gain for typical and atypical antipsychotic drugs. 总被引:1,自引:0,他引:1
Andrew J Goudie Jason C G Halford Terry M Dovey Gillian D Cooper Joanna C Neill 《Neuropsychopharmacology》2003,28(12):2209; author reply 2210-2209; author reply 2211
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Post-traumatic stress disorder in the general population. Findings of the epidemiologic catchment area survey 总被引:13,自引:0,他引:13
There have been numerous studies of post-traumatic stress disorder in trauma victims, war veterans, and residents of communities exposed to disaster. Epidemiologic studies of this syndrome in the general population are rare but add an important perspective to our understanding of it. We report findings on the epidemiology of post-traumatic stress disorder in 2493 participants examined as part of a nationwide general-population survey of psychiatric disorders. The prevalence of a history of post-traumatic stress disorder was 1 percent in the total population, about 3.5 percent in civilians exposed to physical attack and in Vietnam veterans who were not wounded, and 20 percent in veterans wounded in Vietnam. Post-traumatic stress disorder was associated with a variety of other adult psychiatric disorders. Behavioral problems before the age of 15 predicted adult exposure to physical attack and (among Vietnam veterans) to combat, as well as the development of post-traumatic stress disorder among those so exposed. Although some symptoms of post-traumatic stress disorder, such as hyperalertness and sleep disturbances, occurred commonly in the general population, the full syndrome as defined by the Diagnostic and Statistical Manual of Mental Disorders, third edition, was common only among veterans wounded in Vietnam. 相似文献
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Terry Lynn Gall 《Quality of life research》2004,13(8):1357-1368
This study explored the role of relationship with God with respect to the quality of life of men with prostate cancer. Thirty-four men with prostate cancer completed questionnaires on demographic and illness factors, aspects of relationship with God (e.g., God image), nonreligious resources (e.g., optimism) and physical, social and emotion functioning. Results showed that relationship with God was a significant factor in the prediction of role, emotional and social functioning for these men after controlling for age, reported severity of treatment reactions and nonreligious resources. Notably, different aspects of relationship with God (e.g., causal attribution) evidenced different associations with functioning and the nonreligious resource of perceived health control. Such results suggest that relationship with God may function in a complex manner as a resource in coping with prostate cancer. Longitudinal research is needed to clarify the role of religious/spiritual resources in the short- and long-term quality of life of men with prostate cancer. 相似文献
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Douglas Wholey PhD ; Ira Moscovice PhD ; Terry Hietpas PharmD ; Jeremy Holtzman MD MS 《The Journal of rural health》2004,20(4):304-313
The environmental context of patient safety and medical errors was explored with specific interest in rural settings. Special attention was paid to unique features of rural: healthcare organizations and their environment that relate to the patient safety issue and medical errors (including the distribution of patients, types of adverse events associated with learning, information flows, triage and transfer decisions, and culture of safety). Relevant organizational theories and strategies fo medical error reduction and prevention in rural health care settings were identified. Financial and technical assistance are needed to support the systematic collection of data from rural hospitals and other entities and to enhance relevant patient safety practices for rural America. 相似文献
40.
Difficult-to-recruit respondents and their effect on prevalence estimates in an epidemiologic survey 总被引:6,自引:0,他引:6
L B Cottler J F Zipp L N Robins E L Spitznagel 《American journal of epidemiology》1987,125(2):329-339
Generous contact efforts were used to recruit 3,004 respondents into the first wave of the St. Louis Epidemiologic Catchment Area (ECA) project, a psychiatric epidemiologic study of the general population, conducted from 1981-1982. These efforts were analyzed to establish which sociodemographic characteristics or current psychiatric disorders were determinants of difficulty in recruitment. Being young, male, black, a nonrural resident, educated, and full-time employed were the demographic characteristics associated with increased contact efforts. Persons currently meeting criteria for an alcohol disorder required almost 20% more contact attempts than those without the disorder; this difficulty lay both in their being less available for an initial contact and refusing at a higher rate once contacted. An optimal recruitment effort cutoff point is provided, and a method is suggested for detecting that optimal point in the course of ongoing studies. 相似文献