全文获取类型
收费全文 | 1593篇 |
免费 | 1篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 9篇 |
金属工艺 | 6篇 |
机械仪表 | 3篇 |
矿业工程 | 3篇 |
轻工业 | 5篇 |
石油天然气 | 1篇 |
无线电 | 3篇 |
一般工业技术 | 36篇 |
冶金工业 | 1525篇 |
原子能技术 | 1篇 |
自动化技术 | 1篇 |
出版年
2022年 | 1篇 |
2021年 | 4篇 |
2020年 | 1篇 |
2018年 | 1篇 |
2017年 | 2篇 |
2016年 | 4篇 |
2015年 | 3篇 |
2014年 | 1篇 |
2013年 | 3篇 |
2012年 | 5篇 |
2011年 | 1篇 |
2009年 | 4篇 |
2008年 | 2篇 |
2007年 | 4篇 |
2005年 | 2篇 |
2004年 | 5篇 |
2003年 | 2篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 25篇 |
1998年 | 405篇 |
1997年 | 254篇 |
1996年 | 166篇 |
1995年 | 94篇 |
1994年 | 75篇 |
1993年 | 100篇 |
1992年 | 10篇 |
1991年 | 13篇 |
1990年 | 8篇 |
1989年 | 7篇 |
1988年 | 8篇 |
1987年 | 9篇 |
1986年 | 7篇 |
1985年 | 7篇 |
1983年 | 2篇 |
1982年 | 14篇 |
1981年 | 23篇 |
1980年 | 28篇 |
1979年 | 3篇 |
1978年 | 4篇 |
1977年 | 92篇 |
1976年 | 183篇 |
1975年 | 7篇 |
1973年 | 1篇 |
1970年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有1594条查询结果,搜索用时 15 毫秒
81.
OBJECTIVES: The objectives of the study were to assess the suitability of a service for provision of emergency hormonal contraception by nurses. METHODS: Retrospective analysis was carried out of data obtained from the case records of 500 consecutive women who attended ABACUS (a city center-based family planning clinic in Liverpool, UK) for emergency contraception during the 7th and 9th months of the first year (1994) of the service. Similar data were collected for 100 consecutive women during 1 month of the third year (June 1996). The number of women who received emergency hormonal contraception was noted. In particular, details pertaining to the reasons for referral to the doctor and the trend of referrals were noted. RESULTS: The results indicate that during the first year the nurses independently issued emergency hormonal contraception to 37% of the women. They referred the remaining 63% to the medical staff. One-third of referrals were for ongoing contraception, especially oral contraception. Another third of referrals appeared to be due to 'nurse anxiety', as no medical or other cause was found for these referrals. During the third year, nurses dispensed emergency hormonal contraception to 64% of women. Among the remaining 36% of women who were referred to the doctor, 19% needed hormonal contraception. Referral reflecting 'nurse anxiety' significantly declined (1%) compared to the first year of service. CONCLUSIONS: Ongoing contraception, particularly initiation of oral contraception, was one of the main reasons for referral during the first year. Referral due to 'nurse anxiety' significantly declined with continued experience and may have reflected initial anxiety and the learning curve. With increased experience over the first 2 years, the outcome of this service showed encouraging improvement. The nurses now dispense emergency hormonal contraception to a majority of women. 相似文献
82.
83.
84.
85.
86.
87.
More than 600 cases of ovarian tumors were analyzed for histological type, age of patient, bilateral occurrence, mobility and malignant degeneration in restant ovaries. Tumors of germinal epithelial origin show the highest incidence (24%) of malignant degeneration, tumors of germ cells the lowest (3,5%). Incidence of malignant degeneration increases in relation to the age of the patient from 2% (and under 30 years) to 36,5% (60-70 years). Each form of tumor has its typical age peak, which is about 20 years higher for carcinomas than for their benign counterpart. Bilateral ovarian tumors are malignant in 29%, one-sided only in 13%. Among freely movable ovarian tumors, only 6% enclose a malignant tumor, among adhaerent ones 34%. The examination of the prognosis of granulosacell-tumors, dysgerminomas and teratoblastomas is based on a larger material. 相似文献
88.
A reduction of red cell SA in patients following acute myocardial infarction is reported and the effects of SA-depleted red cells on cardiac index and alveolar capillary blood flow in the dog are described. The mean red cell SA in 26 patients following acute myocardial infarction was 0.021 +/- 0.001 compared with a mean of 0.031 +/- 0.002 mumol./0.1 ml RBC in 12 normal subjects (p less than 0.01). In five dogs injected with neuraminidase, an enzyme which removes SA from the red cell membrane, a 43% decrease in mean cardiac index from 2.3 +/- 0.22 to 1.3 +/- 0.16 (p less than 0.01) occurred. In films of the pulmonary microcircuation the mean widths of typical alveolar capillary beds decreased 42.6% +/- 5% (p less than 0.01). In three other dogs, autotransfusion with SA-depleted stored blood resulted in a 25% decrease in mean cardiac index from 2.0 +/- 0.21 to 1.5 +/- 0.21 (p less than 0.2), and a 21.7% +/- 0.9% (p less than 0.01) decrease in mean widths of typical alveolar capillary beds. We conclude that a reduction of red cell SA follows acute myocardial infarction and that SA-depleted red cells decrease cardiac index and alveolar capillary blood flow in the dogs. 相似文献
89.
90.