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1.
The possibility that exposure to powerline frequency (60-Hz) magnetic fields might affect the form or intensity of epileptic seizures, induced by administration of pentylenetetrazol (PTZ) in rats, was examined. Male adult rats were exposed to either 60-Hz magnetic fields with intensities of up to 1.85 gauss (185 microT) or to a sham field condition, for 1 h prior to injections of PTZ (45-75 mg/kg). The subsequent seizures were monitored and recorded on videotape and any subsequent mortalities were noted. Exposure to 60-Hz magnetic fields prior to administration of PTZ was found to significantly (P less than 0.005) reduce the lethality of the drug-induced seizures. The LD50 for the sham-exposed group was 65.88 mg/kg, whereas for the 60-Hz magnetic field-exposed rats, the LD50 was 85.33 mg/kg. In some experiments exposure to the 1.0 and 1.5 gauss magnetic fields also produced significant (P less than 0.05) reductions in seizure durations. These findings suggest that acute exposure to low intensity 60-Hz magnetic fields has an inhibitory effect on the lethality and expression of PTZ-induced seizures in rats. Some possible mechanisms, which could account for these observed effects of magnetic field exposure on seizures, are discussed. 相似文献
2.
Listeria monocytogenes was identified as the etiological agent in the cutaneous and febrile illness of a 64-year-old male who acquired the organism as a result of contact with the genital tract of a cow while assisting in the delivery of a stillborn calf. 相似文献
3.
Deborah Bray Preston Anthony R D'Augelli Cathy D Kassab Richard E Cain Frederick W Schulze Michael T Starks 《AIDS education and prevention》2004,16(4):291-303
Research investigating predictors of risky sexual behavior of rural MSM is sparse, even though the prevalence of HIV in rural areas has increased. This study explored two sets of predictors of 93 rural MSM's levels of risky sexual behavior: mental health variables and stigma emanating from men's family members, health care professionals, and people in the rural communities in which they live. Over 47% of the men were found to be at modified high to high risk. Logistic regression using a continuation logit model was used to test the relationship of the predictor variables and the four levels of risk. Findings indicate that self-esteem was predictive of the highest sexual risk behavior but not lower levels of risk. Stigma was predictive of modified high sexual risk when compared to low and no risk categories. No variables differentiated men at low risk from men at no risk. 相似文献
4.
Summary A randomised, comparative study is reported of single intravenous doses of cephradine 2 g or cefuroxime 1.5 g given as prophylactic cover for total hip replacements in 40 patients. The serum and bone levels of cephalosporin achieved were higher in the cephradine treated group in proportion to the higher dose employed. Both agents provided adequate bone levels on average, cephradine 25.34 mcg/g, cefuroxime 17.39 mcg/g, although bone penetration was more variable with cefuroxime.
Résumé Dans cette étude comparative randomisée, 40 patients ont reçu une dose intraveineuse unique de 2 g de céphradine ou de 1,5 g de céfuroxime en tant que couverture prophylactique d'arthroplastie totale de hanche. Les concentrations sériques et osseuses de céphalosporine ont été plus élevées dans le groupe traité par la céphradine, en rapport avec l'utilisation d'une dose plus importante. Des concentrations osseuses adéquates ont été obtenues en moyenne avec les deux produits (25,34 mcg/g avec la céphradine et 17,39 mcg/g avec le céfuroxime) bien que la pénétration osseuse ait été plus variable avec le céfuroxime.相似文献
5.
I Sircar B L Duell M H Cain S E Burke J A Bristol 《Journal of medicinal chemistry》1986,29(11):2142-2148
Several N-substituted 3H-indeno[1,2-c]pyridazinones (1-23) and a benzo[h]cinnolinone (24), which were designed as rigid structural modifications of 5-alkyl-4,5-dihydro-6-[4-N-substituted phenyl]-3(2H)-pyridazinones (ib-d), were synthesized and evaluated for positive inotropic activity. Most of these tricyclic pyridazinones (1-11, 14-15, 22-23) demonstrated potent positive inotropic activity comparable to the corresponding phenylpyridazinones related to I. 相似文献
6.
The Relationship Between Daily Life Stress and Gastrointestinal Symptoms in Women with Irritable Bowel Syndrome 总被引:3,自引:0,他引:3
Rona L. Levy Kevin C. Cain Monica Jarrett Margaret M. Heitkemper 《Journal of behavioral medicine》1997,20(2):177-193
Research on irritable bowel syndrome (IBS), a functional disorder of the gastrointestinal (GI) system, has linked GI symptoms to stress. This study examined the relationship between daily stress and GI symptoms across women and within woman in IBS patients (n = 26), IBS nonpatients (IBS-NP; n = 23), and controls (n = 26), controlling for menstrual cycle phase. Women (ages 20–45) completed daily health diaries for two cycles in which they monitored daily GI symptoms and stress levels. The Life Event Survey (LES) was used as a retrospective measure of self-reported stress. The across-women analyses showed higher mean GI symptoms and stress in the IBS and IBS-NP groups relative to controls but no group differences in LES scores. The within-woman analyses found a significant and positive relationship between daily stress and daily symptoms in both the IBS-NP and the IBS groups. Controlling for menstrual cycle had no substantial impact on the results. 相似文献
7.
Research on the neurobiology of learning and memory has been guided by two major theories: (i) memory as a psychological process and (ii) memory as a change in synaptic neural connectivity. It is not widely recognised that not only are these theories different but, moreover, they are fundamentally incompatible. Confusion concerning basic concepts in the learning and memory field in mammals has lead to the creation of an extensive but often inconclusive experimental literature. However, one important conclusion suggested by recent work in this field is that experience-dependent changes in neural connectivity occur in many different brain systems. Particular brain structures, such as the hippocampus, do not play any uniquely important role in experience-dependent behavior. Research in learning and memory can be best pursued on the basis of biological studies of animal behavior and a cellular approach to brain function. 相似文献
8.
Cain, an oncologist and chair of her medical center's ethics advisory committee, and Reagan, a clinical ethicist, debate the pros and cons of compensation for ethics committee members. Among the issues raised are the value of monetary compensation in our society, the assumption of virtue as its own reward, and the potential for conflict of interest if ethics committee members are paid. 相似文献
9.
Husaini BA Sherkat DE Levine R Bragg R Van CA Emerson JS Mentes CM 《Journal of the National Medical Association》2002,94(2):100-106
This study examines the effectiveness of breast cancer screening education programs on mammography rates among African-American women 40 years of age and over. We conducted two types of educational programs in community settings, primarily in African-American churches. Three-month follow-up interviews were used to determine whether women who participated in programming were more likely to get a mammogram if they had not had a mammogram in the last year. Our results demonstrate that the educational programs significantly increased the likelihood of getting a mammogram when compared to a control group that received no educational programming. Further, we found that the programs were effective for motivating breast cancer screening in housing projects as well as in the churches, and that the effectiveness of the programs remained even when we controlled for socioeconomic status, depression, and age. 相似文献
10.
Adenosine decreases post-ischaemic cardiac TNF-alpha production: anti-inflammatory implications for preconditioning and transplantation. 总被引:1,自引:0,他引:1
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D R Meldrum B S Cain J C Cleveland Jr X Meng A Ayala A Banerjee A H Harken 《Immunology》1997,92(4):472-477
Tumour necrosis factor-alpha (TNF-alpha) is an autocrine contributor to myocardial dysfunction and cardiomyocyte death in ischaemia-reperfusion injury (I/R), sepsis, chronic heart failure and cardiac allograft rejection. Cardiac resident macrophages, infiltrating leucocytes, and cardiomyocytes themselves produce TNF-alpha. Although adenosine reduces macrophage TNF-alpha production and protects myocardium against I/R, it remains unknown whether I/R induces an increase in cardiac TNF-alpha in a crystalloid-perfused model (in the absence of blood), and, whether adenosine decreases cardiac TNF-alpha and protects function after I/R. To study this, isolated rat hearts were crystalloid-perfused using the Langendorff method and subjected to I/R, with or without adenosine pretreatment. Post-ischaemic cardiac TNF-alpha (enzyme-linked immunosorbent assay and bioassay) and function were determined (Langendorff). I/R increased cardiac TNF-alpha and impaired myocardial function. Adenosine decreased cardiac TNF-alpha and improved post-ischaemic functional recovery. This study demonstrates that: first, I/R induces an increase in cardiac tissue TNF-alpha in a crystalloid-perfused model: second, adenosine decreases cardiac TNF-alpha and improves post-ischaemic myocardial function; third, decreased cardiac TNF-alpha may represent a mechanism by which adenosine protects myocardium; and fourth, adenosine-induced suppression of cardiac TNF-alpha may provide an anti-inflammatory link to preconditioning and have implications for cardiac allograft preservation. 相似文献