首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1441篇
  免费   1篇
  国内免费   1篇
化学工业   3篇
轻工业   6篇
无线电   1篇
一般工业技术   2篇
冶金工业   1430篇
自动化技术   1篇
  2023年   1篇
  2019年   1篇
  2018年   1篇
  2013年   3篇
  2010年   2篇
  2008年   1篇
  2003年   4篇
  1999年   44篇
  1998年   500篇
  1997年   250篇
  1996年   169篇
  1995年   102篇
  1994年   65篇
  1993年   73篇
  1992年   7篇
  1991年   14篇
  1990年   11篇
  1989年   18篇
  1988年   10篇
  1987年   9篇
  1986年   13篇
  1985年   14篇
  1983年   3篇
  1982年   9篇
  1981年   8篇
  1980年   12篇
  1978年   6篇
  1977年   36篇
  1976年   54篇
  1962年   1篇
  1955年   1篇
  1954年   1篇
排序方式: 共有1443条查询结果,搜索用时 15 毫秒
91.
92.
93.
94.
95.
Dairy animals, ranging from days 8 to 13 of the estrous cycle, were fitted with indwelling jugular catheters 1 day prior to either intramuscular injection of prostaglandin F2alpha free acid (30 mg, n=4) or intrauterine deposition of prostaglandin F2alpha free acid (10 mg, n = 3). Blood samples were collected at 6, 4, 2, and 0 h prior to administration of prostaglandin F2alpha and at 1, 3, and every 2 h thereafter until ovulation. Progestins, estradiol, and luteinizing hormone in plasma were measured by radioimmunoassay. Hormonal changes and interrelationships within animals were evaluated by least squares analyses. Decreases in progestins of plasma within 24 h indicated prostaglandin F2alpha induced luteolysis in six of the seven animals. Estradiol increased linearly from time of injection to 52 h postinjection. Intervals from administration of prostaglandin to onset of estrus, peak of luteinizing hormone, and ovulation were 74.9 +/- 21, 78.8 +/- 21, and 99.5 +/- 19 h.  相似文献   
96.
This paper introduces the use of optimized solvent system with twice-ascending-development in twin trough chamber on TLC silica gel plate for the separation of protoberberine-type alkaloids contained in Rhizomata of Coptis spp. Nine to eleven spots including the main and the 'minor' alkaloids in the samples can be observed on the chromatograms obtained under controlled conditions. The fluorescence and UV-absorption TLC scanning profile can serve as fingerprint for the analysis of commercial samples of Rhizomata of Coptis spp.  相似文献   
97.
98.
As children and adults with developmental disabilities and special health care needs are integrated into home, school, and community life, nurses are being required to provide leadership, advocacy, and training in community settings to a much greater extent than in the past. To assess the school and community need for formal graduate preparation for nurses who work with individuals with developmental disabilities and/or special health care needs, 25 nurses in leadership positions representing urban and rural health agencies throughout Minnesota took part in a 5-hour focus group discussion. Analysis of data summarized from this process shows five features of the recommended curriculum necessary for advanced practitioners in this specialty area: (a) discipline-specific core competencies, (b) discipline-specific specialty competencies, (c) genetic competencies not specific to nursing but necessary to function in nursing roles, (d) interdisciplinary and intradisciplinary learning experiences, and (e) clinical experiences with preceptors. The authors recommend the development of interdisciplinary graduate programs designed to prepare nurses to assume leadership roles in school health, public health, home health care, and systems management that will affect public policy and, ultimately, promote change in the systems charged with responsibility to serve this population.  相似文献   
99.
PURPOSE: To develop an informative consent form for angiography that can be read and understood by a patient with an eighth-grade level of education. MATERIALS AND METHODS: Consent forms from 125 medical centers were evaluated with RightWriter 4.0 software. The readability index, a measure of educational grade level needed to understand a document, was determined for each form. Features of forms and discussion of complications were evaluated. A model consent form was developed. RESULTS: Analysis of 27 consent forms revealed a mean readability index of 14.2; to adequately understand the documents, an average of 2.2 years of college were required. Alternatives to the procedure were listed in 14 forms (52%). All consent forms listed potential complications, but only 15 (56%) identified specific numeric risks, and attempts to classify complications according to severity were made in only five (18%). CONCLUSION: An angiography consent form has been developed that can be understood with an eight-grade level of education. It should allow patients to more easily understand the procedure and its risks, benefits, and alternatives. It remains the obligation of the physician to tailor the discussion for each procedure to meet the needs of each patient.  相似文献   
100.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号