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101.
Two surveys of a Northern Ireland student sample were conducted in 1987 and 1988. A total of 419 female and 201 male subjects completed self-administered anonymous questionnaires concerning their behavior, knowledge, and attitudes towards sex, AIDS, homosexuality, contraception, and relationships. Results indicated a relatively low level of sexual experience, and for those with experience, relatively few partners. The possible influences of gender and religiosity on sexual behavior and attitudes, in the context of Northern Ireland, are discussed. Subjects reported considerable variation in the amount of sex education, but the majority received little or none. This student sample held relatively conservative attitudes towards love, sex, and marriage and this was particularly true for females and for regular churchgoers. In addition, attitudes towards homosexuality were negative (particularly among regular churchgoers). Attitudes towards contraception were more positive than expected among Catholic subjects, and few indicated that they would refuse to use contraceptives on principle. Responses to items about AIDS were highly uniform, suggesting that much of the information made available to the public has been absorbed. However, the lack of uniformity of response to more general items about sex, relationships, and contraception may indicate that fundamental changes in sexual behavior are unlikely to be brought about by influencing a rather narrowly defined set of attitudes about AIDS. 相似文献
102.
During reproductive maturation of female insects, the acquisition of sexual receptivity is coordinated with ovarian development. Juvenile homone regulates vitellogenesis in the ovaries, but the action of this hormone in the development of sexual behavior is less well-understood. A strain ofDrosophila melanogaster carrying a mutation in theapterous gene(ap
4) was known to exhibit arrested vitellogenesis (rescuable by applying exogenous juvenile hormone), sterility of both sexes, and a deficiency of juvenile hormone. In this study, we examined the effects of mutations ofap on female receptivity and its relationship to juvenile hormone. We observed abnormally low female receptivity in homozygousap strains, and heteroallelic combinations ofap mutations exhibited low receptivity. For female receptivity,ap showed no dominance (i.e.,ap/ap
+ was intermediate betweenap/ap andap
+/ap
+). Low receptivity mapped genetically to theap locus. The reduction in female receptivity in these mutants is positively correlated with levels of juvenile hormone synthesized by their corpora allata.This work was supported in part by The Scheinfeld Center for Humans Genetics in the Social Sciences (J.R.), The National Science Foundation (BNS-882 1339 to J.R.), BARD (No. IS-1664-89R to D.S.), The Israel Cancer Research Fund (grant to D.S.), The Rekanati Foundation of Tel Aviv University (grant to D.S.), and The Israeli Fruit Council (award to M.A.) 相似文献
103.
Katherine A. Vittes Ph.D. Susan B. Sorenson Ph.D. 《The Journal of adolescent health》2006,39(6):929-932
In a survey of 5657 community-residing adolescents, those who said they could get a handgun in two days reported similar and those who said they could not get a handgun reported fewer risk behaviors and less violence perpetration and victimization than adolescents who have their own handgun. Adolescents who said they could get a handgun reported more exposure to and experience with firearms than those who said they could not get a handgun. Risk reduction efforts regarding adolescents should be expanded to include adolescents who say they can get a handgun. 相似文献
104.
Kelvin L Chou Maria L Moro-De-Casillas Melissa M Amick Leora L Borek Joseph H Friedman 《Movement disorders》2007,22(3):411-414
We examined the relationship between testosterone levels, violent dreams, and REM sleep behavior disorder (RBD) in 31 men with Parkinson's disease (PD): 12 with clinical RBD and 19 without. All PD patients with clinical RBD experienced violent dreams, but none of the 19 non-RBD patients reported violent dreams. While dream content appears to be more aggressive in PD patients with clinical RBD, the presence of violent dreams or clinical RBD is not associated with testosterone levels in men with PD. 相似文献
105.
BCPT对慢性应激抑郁大鼠行为及体重的影响 总被引:7,自引:0,他引:7
目的:研究一种拟青霉代谢物提取物(BCPT)对慢性轻度不可预见性应激(CUMS)大鼠行为及体重的影响.方法:采用CUMS法,造成大鼠抑郁模型,定期测量BCPT对该模型大鼠的体重及糖水消耗量,以开野实验的方法测定大鼠水平及垂直活动.结果:与正常组相比,模型组大鼠体重增长缓慢,糖水消耗量明显下降,水平活动和垂直活动均明显下降.与模型组大鼠相比,BCPT组大鼠体重增长略有提高,糖水消耗量明显增加,水平活动和垂直活动均明显增加.结论:本模型为较理想的抑郁模型,BCPT能明显改善抑郁大鼠的行为活动及体重,提示BCPT具有一定的抗抑郁作用. 相似文献
106.
Josefa Vega-Matuszczyk Viveka Hillegaart Knut Larsson Sven Ahlenius 《Brain research》1993,630(1-2):82-87
Regional changes in the rate of brain monoamine synthesis were monitored in male rats exposed to, but prevented from physical contact with, an estrous or an ovariectomized female. The in vivo rate of tyrosine and tryptophan hydroxylase activities were estimated by measuring the accumulation of DOPA and 5-HTP following inhibition of cerebral aromatic l-amino acid decarboxylase by means of 3-hydroxybenzylhydrazine (NSD-1015) treatment (100 mg/kg i.p.) 5 min upon NSD-1015 treatment, the males were exposed to an intact estrous female or an ovariectomized female for 20 min before decapitation and brain dissections. Exposure to an estrous female produced an increased rate of tyrosine and tryptophan hydroxylase activity in the medial prefrontal cortex, the dorso-lateral neostriatum and in the ventral neostriatum, in comparison with home-cage controls. By the same comparison, exposure to an ovariectomized female resulted in an increased rate of tyrosine hydroxylase activity in the medial prefrontal cortex, byt not in the neostriatal areas, whereas tryptophan hydroxylase activity was unaffected. Finally, exposure to the empty test cage, with no stimulus females present, did not produce any statistically significant changes in the rate of tyrosine or tryptophan hydroxylase activity in any of the brain areas sampled. Taken together with recent findings from this laboratory, the present results demonstrate that the level of sexual motivation brought about by the olfactory, auditory and/or visual stimulation of a receptive female is associated with an increased demand on catecholamine and 5-hydroxytryptamine synthesis in the limbic forebrain of the male rat. The finding that the presence of an unestrous female produced an enhanced demand on tyrosine hydroxylase activity in the medial prefrontal neocortex demonstrates that the sexual incentive provided by the estrous female may not be the only factor responsible for all the effects observed in the present study. In fact, there is a distinct possibility that the intense challenge produced by sexually significant stimuli is but an endpoint, and that the changes found in forebrain monoamine synthesis is a reflection of an environmental challenge not necessarily specifically linked to the sexual behavior. 相似文献
107.
成骨细胞与血管内皮细胞联合培养的生物学特性 总被引:7,自引:1,他引:6
目的探讨成骨细胞与血管内皮细胞联合培养的生物学特性. 方法取2周龄乳兔颅盖骨及肾脏皮质传代培养制备成骨细胞(A组)、血管内皮细胞(B组)及成骨细胞与血管内皮细胞联合培养(C组),用Ⅰ型胶原和血管Ⅷ因子免疫细胞化学染色鉴定成骨细胞和血管内皮细胞,倒置相差显微镜和组织学染色观察细胞的生长特性和细胞相容性,检测碱性磷酸酶 (alkaline phosphatase,ALP)活性,观察血管内皮细胞对成骨细胞产生的ALP活性有无影响,MTT法检测细胞活力,分析细胞生长和增殖情况. 结果免疫细胞化学染色证实,培养的细胞为成骨细胞和血管内皮细胞.倒置相差显微镜、HE和Masson染色均显示两种细胞混合生长良好.ALP检测结果:C组ALP活性明显高于A组和B组(P<0.01),A组高于B组(P<0.05).MTT检测结果表明:C组细胞早期增殖较慢,而后期增殖较快. 结论成骨细胞与血管内皮细胞具有良好的相容性,血管内皮细胞能够增强成骨细胞的ALP活性,提高成骨细胞的增殖能力.联合培养细胞具有很强的增殖潜能. 相似文献
108.
John R. Glowa 《Drug development research》1990,20(4):411-428
Volatile organic solvents exhibit a range of behavioral effects from the insidiously toxic to the beneficial. Solvents impair performance in a concentration-dependent manner that depends on the unique physicochemical properties of each solvent. The toxic effects of solvents range greatly but, at sufficient concentrations, or after prolonged exposure, neurotoxic effects are often seen. Many solvents are both self-administered and exhibit noxious properties. Solvents may produce some of their primary behavioral effects by altering γ-amino-butyric acid (GABA) function. Further studies related to mechanism may lead to a better understanding of means to protect individuals from the effects of solvent exposure, as well as further our knowledge of solvent abuse. Solvents activate the stress axis and, as such, their neuroendocrine effects deserve further characterization, because chronic exposure may result in altered neuronal activity similar to that associated with chronic stress. Methods have been developed to assess for risk of the effects of exposure to solvents, detailing the lowest levels of solvent expected to produce behavioral impairment. Results from these procedures should be applied to the different end points described. 相似文献
109.
David W Lawrence 《Injury prevention》2007,13(4):232-236
OBJECTIVE: To assess the capacity of textword queries to provide a comprehensive listing of articles on injury prevention and safety promotion (IPSP) concepts in a literature database. METHODS: All terms used to search SafetyLit (a database of scholarly literature selected for its relevance to the IPSP field) during the years 2000-2005 were listed and then examined to identify terms that are synonyms for the same concept. Terms were grouped by concept, the number of queries that used terms within each concept category were summed, and the concepts were then ordered by the total number of searches for each concept category. For each textword, the proportion of all articles for that concept that could be found by using it alone was calculated. RESULTS: Each of the 25 most searched-for concepts has 4 to 40 synonyms. Sixteen of the concepts required queries using two or more terms to find 75% of the available articles. Few searchers used a sufficient number of textword synonyms in their queries to return a complete listing of the available material. CONCLUSION: On the basis of this study, queries using only one or two textword terms are insufficiently sensitive to find all relevant journal articles about an IPSP concept. 相似文献
110.
Peripheral and central injections of recombinant human interleukin-1β (IL-1β) have been shown to decrease social exploration and to induce body weight loss in rats. To characterize the receptor mechanisms of these effects, we used as a tool a specific antagonist of the receptors of IL-1, IL-1ra. Intraperitoneal (i.p.) administration of IL-1ra (8 mg/kg) blocked the effect of i.p. injection of IL-1β (4 μg/rat) on social behaviour but not on body weight. Central administration of IL-1ra (60 μg/rat, i.c.v.) abrogated the effects of centrally administered IL-1β (30 ngn/rat, i.c.v.) on both social behaviour and body weight. Central injection of IL-1ra (4 μg/rat, i.c.v.) also attenuated the effects of i.p. administered IL-1β (4 μg/rat) on social behaviour but not on body weight. These results suggest that the effects of IL-1β on social behavior are mediated centrally and that its effect on the loss of body weight involves different receptor mechanisms. 相似文献