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This article replicates for Kinsey's male sample the decade-of-birth analyses provided in the Kinsey female volume. Five generations of male respondents are compared in terms of total frequency of sexual activity, and frequency and incidence of nine specific categories of sexual behavior. In general, unmarried males born after 1900 experienced more frequent sexual outlet than did nineteenth-century males. Additionally, the proportion of total outlet devoted to various specific activities varied by birth decade. Solitary masturbation rose somewhat spectacularly in significance with the passing decades, while nocturnal emissions and animal contacts declined. Orgasms provided by heterosexual activities increased slightly for the early twentieth-century generations, but then declined to a point below their nineteenth-century levels. Although homosexual contacts accounted for a constant percentage of total outlet for unmarried males over the five generations, more males in each succeeding generation were actively engaging in homosexual activity, at least on a casual basis. Similarly, although heterosexual contacts accounted for a smaller percentage of all activity among the unmarried in later generations, more of the later-born males had engaged in such activity at least once. For married males, on the other hand, frequency of total outlet was unaffected by generation. A large and stable proportion of this outlet was provided by marital coitus. Although more males in later generations had experienced extramarital contacts, such activities accounted for a small and reasonably stable proportion of total outlet, when frequency of occurrence was considered. Masturbation gained in significance, while nocturnal emissions and homosexual contacts declined, and animal contacts among the married were almost nonexistent in all generations.  相似文献   
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固体光气法合成洛莫司汀   总被引:4,自引:0,他引:4  
以固体光气(三光气)为起始原料,经过在无水甲苯溶液中与环己胺反应生成环己基异氰酸酯,再经与氨基乙醇和氯化亚砜的一锅法反应生成1-(2-氯乙基)—3—环己基脲(氯化物),最后再亚硝化,即得洛莫司汀。原料易得,各步反应条件温和,操作方便,步骤比文献方法(4步)减少一步,总收率由文献方法的23.7%提高为49.8%,适于工业规模制备。  相似文献   
66.
The disparity in resources between economically developed and developing countries presents ethical concerns when commercial sponsors of studies and investigators propose to conduct them with subjects in developing countries. Vulnerable people may be recruited into studies of little health benefit to themselves or their communities and, under undue inducements, may accept disproportionate risks. Reproductive health studies may present women with undue risks. Guidelines have been developed to protect exploitable populations in resource-poor settings, although guarding their right to make informed and voluntary choices poses special challenges. Guidelines pay special attention to pregnant women as research subjects, and may approve and even require their enrollment in studies of products not known to be harmful. Placebo-controlled studies are addressed in contexts where no recognized treatments are routinely accessible. The structure and functions of research ethics review committees present difficult challenges, but they may be mitigated by enlightened international collaboration.  相似文献   
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The abstract to publication ratio (APR) is a measure of the quality of scientific meetings. The aim of the present study was to determine the publication rate of abstracts presented at annual Royal Australian and New Zealand College of Radiologists (RANZCR) conferences, and to identify the publishing journals. All free paper research abstracts (oral or poster) presented by RANZCR radiologists, radiation oncologists and trainees at the four consecutive meetings between 1996 and 1999 were identified retrospectively from conference programmes. The PubMed database ( http:www.ncbi.nlm.nih.govPubMed ) was searched to determine whether or not the abstract had been published as a full paper. Of the 480 free paper research abstracts, 168 (35%) had been published as full articles. The overall abstract to publication ratio for radiology was 29% and for radiation oncology was 41%. Papers were published in a variety of journals but Australasian Radiology accounted for 27%. The mean time between presentation and publication was 16.5 months (median 17 months). These overall abstract to publication ratios are lower than those reported for overseas‐based meetings in each respective area. Guidelines to scientific committees could increase the APR by more rigorous selection of abstracts. Future research should look at barriers to the publication of research findings, and identify ways to assist the publication process.  相似文献   
68.
cDNA arrays and proteomic analyses have allowed the rapid identification of specific genes and proteins implicated in multiple tumor types. These molecules must then be validated as clinically relevant prognostic and predictive markers, and this translational research is best conducted in the context of clinical trials. Outcomes data and clinical specimens collected in the ‘Arimidex’, Tamoxifen, Alone or in Combination (ATAC) study, for example, can now be used to compare the expression of biomarkers with clinical outcomes. In this study, adjuvant tamoxifen and anastrozole (‘Arimidex’) were compared alone and in combination in more than 9000 women with breast cancer. Anastrozole was found to be superior to tamoxifen in terms of disease-free survival, time to recurrence, and reduction in the incidence of contralateral tumors. Importantly, tissue specimens from surgical excision, local relapse, and contralateral breast cancer were collected and paraffin-embedded for storage. In the TA01 (TransATAC) program, these specimens will be studied (after obtaining patient consent) using tissue microarrays; tissue biopsy cores 0.6 mm in diameter will be removed from donor blocks and placed on recipient blocks, which will be sectioned to allow the simultaneous analysis of the same samples for multiple biomarkers. These analyses can help determine differential benefits of treatment with anastrozole or tamoxifen, depending on the expression of particular biomarkers in tumor cells. This research also should clarify de novo and acquired resistance mechanisms, and the validation of relevant molecular pathways could guide the development of new drugs. Ultimately, the TA01 program has the potential to favorably impact treatment choices for breast cancer. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
69.
Chronic illness in adolescents: Transfer or transition to adult services?   总被引:2,自引:0,他引:2  
It is widely believed that the improved survival of young people with chronic diseases will be associated with the development of appropriate services within the adult healthcare domain. There is, however, little evidence to suggest that this is happening at a rate commensurate with clinical requirements. This paper highlights the multiplicity of barriers that impede the development of transition services to facilitate the transfer of medical care from the paediatric to the adult domain. Different models of transition care are described, and the terms 'transfer' and 'transition' are differentiated. The clinical demand for service development is highlighted, as well as the need for specific research in this area of healthcare delivery.  相似文献   
70.
环枢关节紊乱症的临床研究   总被引:5,自引:1,他引:5  
环枢关节紊乱症,从发病机理到临床表现,乃是颈椎病中较复杂的疑难顽症。用常规诊治方法,疗效不佳。本研究提出新的诊断依据与治疗方法,对320例病者随机分为治疗组166例(采用改进的诊治方法),对照组154例(用常规诊治方法)对照进行疗效观察。结果显示:治疗组治愈率与总有效率及康复率均高于对照组。有非常显著差异,P<0.01。而疗程较对照组短。环枢关节紊乱症的临床研究有利于颈椎病诊治水平的提高,运用于临床,疗效好,效益高,具有推广应用价值。  相似文献   
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