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991.
The association between mental health disorders beginning in adolescence and disorders in early adulthood is increasingly acknowledged. The mental health of adolescents has not been studied in the eastern area of Taiwan, where the mortality of teenagers is highest in Taiwan. The purpose of this study was to assess psychiatric symptoms among senior high school students in Hualien City, and to identify their associated factors. A total of 1,195 students were selected, via a stratified cluster sampling method, from nine high schools in Hualien City. A self-administered questionnaire was used to assess students' demographic characteristics, neurotic traits, perceived daily-life stress, social support, and psychiatric symptoms. There were 1,141 valid responses. From principal components analysis, depression-anxiety, impulsivity-paranoia, and psychoticism-obsession were found to be the most common self-rated psychiatric symptoms. About 70% of the students felt blue, 48.2% reported urges to injure someone, and 25% felt tense. Overall, about 5% to 10% of high school students had severe psychiatric symptoms. Stress from schoolwork, peer relationships, and neurotic traits were important predictors of psychiatric symptoms. The findings of this study imply that screening for psychiatric symptoms at senior high schools is essential for improving the mental health of students. The mental health care of adolescents should be school-based and in collaboration with medical professionals. Life skills must be taught at school. 相似文献
992.
BS Okun 《Canadian Metallurgical Quarterly》1997,28(3):215-227
This report describes trends and differentials in contraceptive practices among Israeli Jews. Data from two fertility surveys show a heavy reliance on the IUD, little use of sterilization, and declining, but still significant use of withdrawal. The factors associated with the practice of withdrawal are explored. Evidence is found in support of Santow's hypotheses that the degree of sex-role differentiation within marriage and the belief that men hold the authority in reproductive decisionmaking are both positively related to the practice of withdrawal. Fear of oral contraceptives, a dislike of sterilization, and a reliance on the IUD only at greater parities imply a continuing role for withdrawal, especially among Israeli Jewish couples in which wives are less educated and have more traditional sex roles than the wives in other couples. 相似文献
993.
From 1989 to 1992, a longitudinal study of the relationships between different tick species and domestic ungulates in the transmission and amplification of Crimean-Congo hemorrhagic fever (CCHF) virus was undertaken in the Bandia area in Senegal where the presence of the virus had been reported previously. An epizootic occurred in 1991-1992 and 22 strains of CCHF virus were isolated from Hyalomma marginatum rufipes Koch, Amblyomma variegatum (F.), Rhipicephalus guilhoni Morel & Vassiliades, and R. evertsi evertsi Neumann ticks collected from cattle and goats. No human cases were reported. Transmission of CCHF virus in the area involves a complicated pattern including many tick species and hosts. Amplicons of the S fragment (536 bp) of the CCHF genome of 12 isolates from the study were obtained by polymerase chain reaction and analyzed by restriction-length fragment polymorphism. Three different genotypes of CCHF virus were identified and present during the epizootic. One genotype was recovered from A. variegatum, R. guilhoni, and R. e. evertsi and 2 genotypes were isolated from H. m. rufipes. 相似文献
994.
995.
MS Georgiadis BS Schuler JE Brown LV Kieffer SM Steinberg WH Wilson CH Takimoto MJ Kelley BE Johnson 《Canadian Metallurgical Quarterly》1997,15(2):735-743
PURPOSE: To determine the maximum-tolerated dose (MTD) of paclitaxel administered by 96-hour continuous infusion in combination with cisplatin, to determine if the addition of granulocyte colony-stimulating factor (G-CSF) permits significant paclitaxel dose escalation, and to assess the toxicity and preliminary activity of this combination in patients with advanced lung cancer. PATIENTS AND METHODS: Fifty patients with untreated lung cancer were enrolled: 42 had advanced non-small-cell lung cancer (NSCLC) and eight had extensive-stage small-cell lung cancer (SCLC). Patients received paclitaxel doses of 100 to 180 mg/m2/96 hours and cisplatin doses of 60 to 80 mg/m2 as a single 30-minute bolus injection at the end of the paclitaxel infusion. RESULTS: Two of six patients experienced dose-limiting neutropenia at a dose of paclitaxel 140 mg/m2/96 hours and cisplatin 80 mg/m2. With G-CSF support, one of three patients experienced both dose-limiting mucositis and fatal neutropenic sepsis at a dose of paclitaxel 180 mg/m2/96 hours and cisplatin 80 mg/m2. Significant peripheral neuropathy developed in five patients and occurred after six or more cycles of therapy. Thirty-three of 42 patients with NSCLC had measurable disease; the objective response rate was 55%, with two complete responses and 16 partial responses. For all 42 patients with NSCLC, the median time to progression and median survival duration were 5 months and 10 months, respectively. The actuarial 1-year survival rate was 41%. Of eight SCLC patients, four responded to therapy, and the median survival duration for all SCLC patients was 11 months. CONCLUSION: The MTD without G-CSF is paclitaxel 120 mg/m2/96 hours and cisplatin 80 mg/m2, and the MTD with G-CSF is paclitaxel 160 mg/m2/96 hours and cisplatin 80 mg/m2. Infusional paclitaxel with cisplatin is well tolerated and active in patients with advanced NSCLC. 相似文献
996.
These studies were designed to determine whether adult neurogenesis occurs in the dentate gyrus of the tree shrew, an animal phylogenetically between insectivores and primates, and to explore the possibility that this process is regulated by stressful experiences and NMDA receptor activation. We performed immunohistochemistry for cell-specific markers and the thymidine analog bromodeoxyuridine (BrdU), a marker of DNA synthesis that labels proliferating cells and their progeny, on the brains of adult tree shrews subjected to psychosocial stress or NMDA receptor antagonist treatment. Cells that incorporated BrdU in the dentate gyrus of adult tree shrews were primarily located in the subgranular zone, had morphological characteristics of granule neuron precursors, and appeared to divide within 24 hr after BrdU injection. Three weeks after BrdU injection, BrdU-labeled cells had neuronal morphology, expressed the neuronal marker neuron specific enolase, and were incorporated into the granule cell layer. Vimentin-immunoreactive radial glia were observed in the dentate gyrus with cell bodies in the subgranular zone and processes extending into the granule cell layer. Exposure to acute psychosocial stress resulted in a rapid decrease in the number of BrdU-labeled cells in the dentate gyrus. In contrast, blockade of NMDA receptors, with the NMDA receptor antagonist MK-801, resulted in an increase in the number of BrdU-labeled cells in the dentate gyrus. These results indicate that adult neurogenesis occurs in the tree shrew dentate gyrus and is regulated by a stressful experience and NMDA receptor activation. Furthermore, we suggest that these characteristics may be common to most mammalian species. 相似文献
997.
Three new naphthalenes, designated as syriacusins A-C, were isolated from the root bark of Hibiscus syriacus. These compounds were identified as 2,7-dihydroxy-6-methyl-8-methoxy-1-naphthalenecarbaldehyde, 2-hydroxy-6-hydroxymethyl-7,8-dimethoxy-1-naphthalenecarbaldehyde, 1-carboxy-2,8-dihydroxy-6-methyl-7-methoxynaphthalenecarbolactone (1-->8), respectively, on the basis of various spectral studies. The compounds inhibited lipid peroxidation with IC50s of 0.54, 5.90 and 1.02 micrograms ml-1, respectively. The first compound also showed cytotoxicity against some human cancer cell lines with an ED50 of 1.5-2.4 micrograms ml-1. 相似文献
998.
999.
C Chieffo N Garvey W Gong B Roe G Zhang L Silver BS Emanuel ML Budarf 《Canadian Metallurgical Quarterly》1997,43(3):267-277
Given the higher proportion of manufactured foods now available which meet current dietary recommendations, the food supply in developed countries like Australia could be said to be "healthier". Yet the "health" of the diet is often achieved at the expense of the "health" of the environment since ecological problems created a current food production and distribution methods remain unaddressed. Further, nutritional modifications which produce foods that are low in fat, sugar, salt and high in fibre do not necessarily address the concerns consumers have about the food supply. An emphasis solely on the physical health of populations, through improved diet, is out of keeping with current views on health which recognise the importance of overall well-being. Through the development of the concept of "sustaining gastronomy", consumers, food manufacturers and producers, and food regulators can better address the problems inherent in the food system, including those of an environmental nature. 相似文献
1000.
Even when several genetic loci are used in molecular evolutionary studies, each locus is typically analyzed independently of the others. This type of approach makes it difficult to study mechanisms and processes that affect multiple genes. In this work we develop a statistical approach for the joint analysis of two or more loci. The tests we propose examine whether or not nucleotide substitution rates across evolutionary lineages have the same relative proportions at two loci. Theses procedures are applied to 33 genes from the chloroplast genomes of rice, tobacco, pine, and liverwort. With the exception of five clearly distinct loci, we find that synonymous substitution rates tend to change proportionally across genes. We interpret these results to be consistent with a "lineage effect" acting on the entire chloroplast genome. In contrast, nonsynonymous rates do not change proportionally across genes, suggesting that locus-specific evolutionary effects dominate patterns of nonsynonymous substitution. 相似文献