首页 | 官方网站   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   1633篇
  免费   126篇
  国内免费   57篇
医药卫生   1816篇
  2023年   4篇
  2021年   18篇
  2020年   23篇
  2019年   36篇
  2018年   46篇
  2017年   20篇
  2016年   27篇
  2015年   28篇
  2014年   36篇
  2013年   67篇
  2012年   58篇
  2011年   43篇
  2010年   49篇
  2009年   79篇
  2008年   61篇
  2007年   79篇
  2006年   52篇
  2005年   36篇
  2004年   32篇
  2003年   28篇
  2002年   36篇
  2001年   30篇
  2000年   29篇
  1999年   36篇
  1998年   78篇
  1997年   84篇
  1996年   106篇
  1995年   64篇
  1994年   58篇
  1993年   57篇
  1992年   19篇
  1991年   22篇
  1990年   32篇
  1989年   39篇
  1988年   40篇
  1987年   40篇
  1986年   50篇
  1985年   43篇
  1984年   15篇
  1983年   14篇
  1982年   13篇
  1981年   10篇
  1980年   11篇
  1979年   10篇
  1978年   12篇
  1977年   10篇
  1976年   14篇
  1975年   13篇
  1973年   2篇
  1970年   2篇
排序方式: 共有1816条查询结果,搜索用时 531 毫秒
1.
2.
3.
4.
Measurement of ultrasonographic parameters provides information concerning not only bone density but also bone architecture. We investigated the usefulness of ultrasonographic parameters and bone mineral density (BMD) to evaluate the probability of Colles' fracture. Two-hundred eighty-nine postmenopausal women (62.3 +/- 8.7 yr) with (n = 76) and without (n = 213) Colles' fracture were studied. BMD of lumbar spine and proximal femur was evaluated in all women by dual-energy X-ray absorptiometry (DXA) and speed of sound (SOS), broadband ultrasound attenuation (BUA), and stiffness in the calcaneus were measured by a Sahara ultrasonometer (Hologic). Patients suffering from Colles' fracture had lower values of BMD adjusted by height at the lumbar spine, L2-L4 (0.797 g/cm2 vs 0.860 g/cm2), femoral neck (0.685 g/cm2 vs 0.712 g/cm2 ), SOS (1518 m/sg vs 1525 m/sg), and stiffness (74.6 vs 77.7) (p < 0.05). Nevertheless, BUA values were similar in both groups. After stepwise logistic regression analysis, the area found under receiver operating characteristic (ROC) curves was 0.60 for L2L4 and 0.63 for a formula combining L2L4 and height. Our data suggest that patients suffering from Colles' fracture have lower values of BMD by DXA, SOS, and stiffness. However, the ability of these techniques to discriminate is low because the values for the area under ROC curve are 0.60 for L2-L4 and 0.63 for a formula derived of the combination of L2-L4 and height.  相似文献   
5.
6.
7.
8.
BACKGROUND: Since 1997, a number of trials have shown promising results in treating generalized vitiligo with narrowband ultraviolet B (UVB) both in adults and children. However, there is little knowledge concerning the duration and permanency of the treatment-induced repigmentation. OBJECTIVE: Our main objective was to perform a follow-up trial of successfully treated patients receiving narrowband UVB for generalized vitiligo. METHODS: We have investigated to what degree the treatment-induced repigmentation remains stable for up to 2 years post-treatment. We performed an initial open trial including 31 patients with generalized vitiligo. They received narrowband UVB thrice weekly for up to 12 months. Patients experiencing > 75% repigmentation were defined responders and were included in the follow-up trial. Responders were followed every 6 months for up to 2 years after cessation of treatment. We observed the pigmentation status and registered any changes indicating loss of pigmentation and relapse. RESULTS: Eleven of the 31 treated patients were included in the follow-up trial. Six patients had relapse and five patients had stable response 24 months after cessation of treatment. Four out of six relapses were within 6 months post-treatment. CONCLUSION: In our study population of 31 patients with generalized vitiligo, five patients (16%) experienced > 75% stable repigmentation 2 years after cessation of a treatment programme of up to 1 years narrowband UVB therapy.  相似文献   
9.
We report two clinical pregnancies occurring after intracytoplasmic sperm injection (ICSI) using cryopreserved spermatozoa obtained from testicular biopsy, made in two different infertility situations in our clinic. The first patient showed a secretory azoospermia associated with elevated serum follicular stimulating hormone (FSH) level and spermiogenesis maturation arrest. The second patient was affected by azoospermia resulting from bilateral epididymal obstruction. Spermatozoa present in the wet preparation of testicular biopsy made on the day of scrotal exploration were cryopreserved within the testicular tissue for both men. Intracytoplasmic injections were performed at a later date, using spermatozoa prepared from frozen-thawed tissues. In each case, three embryos were obtained and transferred in utero. The transfers resulted in a twin pregnancy for the first case, and in a singleton pregnancy for the second. Living foetuses were seen in the ultrasound scan at the 7th week and both pregnancies are proceeding to date beyond 30 weeks without complications.   相似文献   
10.
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-23

京公网安备 11010802026262号