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21.

Background  

The prevalence of depression is increasing not only among adults, but also among adolescents. Several risk factors for depression in youth have been identified, including female gender, increasing age, lower socio-economic status, and Latino ethnic background. The literature is divided regarding the role of acculturation as risk factor among Latino youth. We analyzed the correlates of depressive symptoms among Latino and Non-Latino White adolescents residing in California with a special focus on acculturation.  相似文献   
22.
Pattern reversal stimuli are widely used for electrophysiological examination of the visual system. To investigate the mechanisms contributing to the pattern reversal EP (PREP) we performed experiments with a trained alert macaque monkey, using both contrast and motion stimuli. It was found that, as in man, for parafoveal and peripheral stimulation the PREP can be constructed from the EPs to the onset and offset of pattern motion. On the other hand foveal stimulation activates the contrast mechanism only.Our conclusion is that pattern reversal data should be considered with caution since pattern reversal can activate motion as well as contrast mechanisms. This ambiguity is not present in the pattern appearance-disappearance stimulus.  相似文献   
23.
Plasmodium falciparum strains from different malaria-endemic regions were grown in continuous culture without human serum. The medium was complemented with Nutridoma-SR instead of serum. All parasite strains developed well in serum-free medium. Two strains were thawed without serum and showed good multiplication in subsequent continuous culture.  相似文献   
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Logging is among the most hazardous forms of employment. However, a comprehensive review of severe logging injuries and their outcome has apparently not been previously undertaken. In the present study we review 51 consecutive injured loggers requiring transfer to a regional Level I trauma center. The average age was 34 years and the mode of injury in 67% was being struck by a falling or rolling log. Orthopedic intervention was required most frequently (49%), with neurologic injury in 43%. Two patients died (4%), both secondary to severe head injury, and both survived less than 24 hours. Importantly, while most severely injured patients survived, they required long hospitalizations and had a 58% permanent disability, with more than half of these being brain or spinal cord related. Although the overall number of workers involved in logging is small, the young average age, the work years lost, and the high risk of permanent disability support continued strong efforts to improve overall safety. Particularly, the high incidence of head injury argues strongly for improved and increased use of safety helmets, which may significantly impact the mortality and morbidity of logging accidents.  相似文献   
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The spinal cord dorsal horn contains neural mechanisms which can greatly facilitate pain. We have recently shown that ‘illness’-inducing agents, such as intraperitoneally administered lipopolysaccharide (LPS; bacterial endotoxin), can produce prolonged hyperalgesia. This hyperalgesic state is mediated at the level of the spinal cord via activation of the NMDA-nitric oxide cascade. However, prolonged neuronal depolarization is required before such a cascade can occur. The present series of experiments were aimed at identifying spinal neurotransmitters which might be responsible for creating such a depolarized state. These studies show that LPS hyperalgesia is mediated at the level of the spinal cord by substance P, cholecystokinin and excitatory amino acids acting at non-NMDA sites. No apparent role for serotonin or kappa opiate receptors was found.  相似文献   
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Nancy Kluck, Scan J. O'Connor, Victor M. Hesselbrock, Allan Tasman and Donald Maier, Lance Bauer: Variation in Evoked Potential Measures Over the Menstrual Cycle: A Pilot Study. Prog. Neuro. Psychopharmacol. Biol. Psychiat. 1992. 16(6): 901–911.

1. 1. The P3 component of a visual event related potential (ERP) was studied for five consecutive weeks in six women with normal menstrual cycles. Serum concentrations of luteinizing hormone (LH), estradiol (E2) and progesterone were studied during the same period.

2. 2. Increases in P3 amplitude, although nonsignificant, were noted in the week preceding onset of menses.

3. 3. No significant changes in reaction times to target/nontarget stimuli were noted over the same time period.

Author Keywords: Event-related potentials; females; menstrual cycle  相似文献   

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