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171.
细菌耐药性是一个严重的医学问题,并由于数量增加的耐药菌对多种结构无关的药物产生耐药而又无新的抗生素可使用而加剧。反义寡核苷酸可特异性抑制或下调同源基因表达,从而能成为基因治疗的首选药物。多年的研究表明:反义寡核苷酸能够有效抑制细菌代谢的基础酶类及致病基因;但也存在着一些尚未完全解决的问题。建议以科学哲学的方法论和系统方法为指导,展开多学科联合的科学活动,推动新型抗菌药的研发,使基因治疗早日实现。  相似文献   
172.
暴力电子游戏的短期脱敏效应:两种接触方式比较   总被引:4,自引:0,他引:4       下载免费PDF全文
郭晓丽  江光荣  朱旭 《心理学报》2009,41(3):259-266
比较主、被动接触暴力电子游戏的脱敏效应,以44名男性大学生为被试,利用生物反馈仪测量被试主动参与游戏或被动观看游戏录像前后,及随后观看暴力视频过程中皮电与心率的变化(脱敏效应的生理指标)。结果表明:(1)暴力电子游戏可以产生脱敏效应。接触游戏15分钟后,暴力游戏组观看暴力视频过程中皮电的增加值明显小于非暴力游戏组;(2)游戏的接触方式对于脱敏效应的程度无显著影响,但主动参与组对于游戏内容知觉到更高的愉快与更低的沮丧  相似文献   
173.
A caffeine versus placebo discrimination procedure was used to determine the lowest caffeine dose that could produce discrimination and self-reported mood effects in normal volunteers. During daily sessions under double-blind conditions, caffeine-abstinent subjects orally ingested a capsule containing 178 mg caffeine or placebo. Before beginning discrimination training, the compounds were identified to subjects by letter codes. Fifteen, 30, and 45 min after capsule ingestion, subjects guessed the capsule's letter code. Correct guesses at 45 min earned money. After each session, subjects received a supplementary capsule containing caffeine or placebo to ensure that, within each phase of the study, subjects received the same daily dose of caffeine equal to the training dose. Five of the 15 subjects acquired the caffeine versus placebo discrimination within the first 20 sessions (greater than or equal to 75% correct); 6 other subjects acquired the discrimination with additional training. Nine subjects who acquired the discrimination were subsequently trained at progressively lower caffeine doses. In general, the lowest dose to produce discrimination (greater than or equal to 75% correct) was also the lowest dose to produce self-reported mood effects: 4 subjects showed discrimination and self-reported mood effects at 100 mg caffeine, 2 at 56 mg, 1 at 32 mg, and 1 at 18 mg. One of these subjects also showed self-reported mood effects at 10 mg. The present study documents discriminative stimulus and self-reported mood effects of caffeine at doses below those previously shown to affect any behavior in normal volunteers.  相似文献   
174.
Maternal serum screening for fetal Down syndrome has been integrated into routine antenatal care in most clinics in Taiwan. We examined the attitudes toward serum screening and the possible implications in women with positive results. From January to July 1995, 276 women were referred to the Genetic Counseling Clinic, Mackay Memorial Hospital for amniocentesis because of positive screening results, and 214 participated in this study. All women opted for amniocentesis after genetic counseling. Over 40% stated that they made decisions independently after being informed of the serum screening. Need for certainty was the most frequently mentioned reason. Two-thirds believed that serum screening could provide a diagnosis. Almost all women would apply for maternal serum screening for future pregnancies. This study demonstrated that Chinese women need more counseling and autonomy regarding maternal serum screening.  相似文献   
175.
We investigated the separate and combined effects of a behavioral intervention and methylphenidate (Ritalin®) on disruptive behavior and task engagement in 3 children with severe to profound mental retardation. The behavioral intervention involved differential reinforcement of appropriate behavior and guided compliance. All 3 children demonstrated decreased disruptive behavior and improved task engagement in response to the behavioral intervention. Two of the 3 children demonstrated similar improvement in response to methylphenidate. Although both interventions were highly effective for these 2 participants, the relative efficacy of the interventions varied between the 2 children. There was no evidence of an additive or synergistic effect of the two interventions, but the high efficacy of each intervention alone limited our ability to detect such effects.  相似文献   
176.
Data from rodent studies have indicated that stress experienced by pregnant mothers may result in behavioral and biological abnormalities in their offspring. However, few studies have examined the effects of prenatal stress on the offspring beyond the childhood period. In this study, 7 prenatally stressed (PNS) monkeys and 7 monkeys from undisturbed pregnancies were tested under mildly challenging conditions at 4 years of age. Following separation from cagemates and group formation, PNS monkeys showed more locomotion, abnormal and disturbance behavior than controls. Controls showed approximately six times more play than PNS animals. The PNS males showed the most clinging to others and the largest increase in contact with other animals over the period. Group differences were also found when the monkeys were observed as groups or alone in a playroom. Controls showed more explanatory behavior in the playroom, whereas PNS monkeys showed more inactivity. Control animals showed a decrease in distress vocalizations over time in the playroom, whereas PNS animals showed the opposite pattern. Control animals spent more time in proximity to and contact with cagemates than PNS animals. These results indicate that prenatal stress can have effects on adaptive and social behavior that persist into adolescence.  相似文献   
177.
The ethical issues in conducting research on preventing HIV infection are among the most complex of any area of human subjects research. This article is an update of a 1987 article that addressed potential conflicts between research design and ethics with respect to AIDS prevention among injecting drug users. The present article reviews current ethical issues that arise in the design and conduct of HIV/AIDS prevention research focused on injecting drug users. Disclaimer: The content of this publication is solely the responsibility of the authors and does not necessarily represent the views of the Beth Israel Medical Center or Johns Hopkins University.  相似文献   
178.
Genetic Counselors are increasingly becoming involved in organizing and facilitating support groups for couples who have terminated a pregnancy because of an abnormal fetal diagnosis. This paper discusses recurrent themes which have emerged in the FATE (Feelings After the Termination Experience) support group which was founded in New Jersey in 1990. By becoming familiar with the issues we have observed in our support group, genetic counselors should be better able to understand and empathize with their patients who make the decision to terminate a much wanted pregnancy. They may also feel better prepared to become involved in organizing and facilitating such support groups.  相似文献   
179.
This study examined the patterns of drug use and criminal activities among Latino arrestees. The findings indicate that while the prevalence of drug use at time of arrest, and in the prior 12 months were significantly lower for Latinos compared to Whites and Blacks, drug use still is of concern for this ethnic group. Almost 50% of Latinos reported drug use in the last year, and more importantly, they were more likely to report using dangerous drugs such as cocaine, heroin, and PCP than any other ethnic group. These findings are even more alarming considering that, for the most part, Latino drug users were treatment-naive, and that less than half perceived a need for drug treatment. Regarding criminal activities, Latinos were less likely to have a history of prior arrests and to have been arrested in the year prior to the interview than any other ethnic group. Interestingly, those immigrants who have resided in the U.S. for less than 1 year were significantly more likely to have been charged with drug-related crimes. U.S. born Latinos were more likely to have been arrested for property crimes, while Central American immigrants were more likely than any other Latino group to have been arrested for violent and domestic violence crimes. Treatment and policy implications of these findings are discussed.  相似文献   
180.
This study examined the relations among developmental test scores, infants' demographic characteristics, and cry features. Cry features were strongly related to developmental test scores at all ages, suggesting that use of the infants' cry characteristics can help to identify those infants at greatest risk for later developmental problems.  相似文献   
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