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   118926篇
  免费   6915篇
  国内免费   1581篇
耳鼻咽喉   1575篇
儿科学   2972篇
妇产科学   4107篇
基础医学   18303篇
口腔科学   3608篇
临床医学   9288篇
内科学   21625篇
皮肤病学   2437篇
神经病学   8006篇
特种医学   4018篇
外国民族医学   3篇
外科学   16767篇
综合类   5213篇
一般理论   34篇
预防医学   8696篇
眼科学   2818篇
药学   10201篇
中国医学   820篇
肿瘤学   6931篇
  2021年   981篇
  2019年   1047篇
  2018年   1611篇
  2017年   1166篇
  2016年   1196篇
  2015年   1442篇
  2014年   1885篇
  2013年   2441篇
  2012年   3548篇
  2011年   3798篇
  2010年   2286篇
  2009年   2049篇
  2008年   3384篇
  2007年   3618篇
  2006年   3596篇
  2005年   3164篇
  2004年   2974篇
  2003年   2770篇
  2002年   2630篇
  2001年   6732篇
  2000年   6926篇
  1999年   5699篇
  1998年   1830篇
  1997年   1378篇
  1996年   938篇
  1995年   863篇
  1992年   3733篇
  1991年   3813篇
  1990年   3554篇
  1989年   3552篇
  1988年   3431篇
  1987年   3282篇
  1986年   3094篇
  1985年   2968篇
  1984年   2048篇
  1983年   1792篇
  1982年   985篇
  1979年   1912篇
  1978年   1184篇
  1977年   986篇
  1976年   918篇
  1975年   1192篇
  1974年   1358篇
  1973年   1413篇
  1972年   1358篇
  1971年   1248篇
  1970年   1137篇
  1969年   1122篇
  1968年   1024篇
  1967年   897篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
131.
A rapid nonsterile short-term assay has been investigated in which percent inhibition of incorporation of the DNA precursor (3H)-thymidine is measured following exposure of tumor cells to the test drugs. To evaluate the usefulness of the short-term assay in providing a rapid reliable assessment of chemotherapeutic response, the short-term assay was compared with the soft agar clonogenic assay. Sensitivity to five anticancer drugs was compared using three human tumor cell lines (epidermoid carcinoma of the oral cavity, pancreatic carcinoma, and bladder carcinoma). The short-term assay produced results that were similar to results of the clonogenic assay in two of the three tumors tested, for three drugs (cis-platin, doxorubicin, and BCNU), but did not detect responses to two antimetabolites (5-FU and MTX) in any tumor. Further studies of this short-term assay should focus on alkylating agents and other nonantimetabolites.  相似文献   
132.
133.
134.
135.
Duchenne and Becker muscular dystrophies are among the most severe and frequent inherited disorders. Being still incurable, medical treatment is concentrated on the carrier diagnosis of the members of the affected families. Here we report the results of the studies of 151 members of 41 Hungarian families, obtained with multiplex PCR amplification of 18 exons as well as the muscle specific promoter region, and haplotype analysis of two polymorphic (CA)n repeat microsatellite loci in introns 45 and 49 of the dystrophin gene. The analysis of 15 deletion-type families revealed a frequency of new mutations not differing significantly from that in the other regions of Europe. We also compared the allele distributions of the two microsatellites in randomly selected normal individuals and affected family members. The allele distribution of STRP45 shows interesting differences between the two populations.  相似文献   
136.
137.
138.
Local hyperthermia of the prostate was used to treat 72 patients who had an indwelling catheter because of urinary retention caused by benign prostatic hypertrophy. One month after completion of treatment 50% of patients were able to dispense with the catheter and 1 year later 40% remained catheter-free. The best results were achieved in patients who underwent 6 to 10 treatment sessions in conjunction with cyproterone acetate 50 mg tid administered during the treatment period only.  相似文献   
139.
The involuntary hospitalisation of psychiatric patients continues to be a controversial issue. All patients certified and admitted to Sterkfontein Hospital under Sections 9 and 12 of the Mental Health Act, No. 18 of 1973, over a 4-week period were surveyed. Almost 40% were admitted as urgent certifications. The majority of the patients in the sample were black, single, urban and had either primary or limited high school education. Most patients had been referred from academic/teaching and provincial hospitals. The average duration of hospital stay was 7.2 weeks, with only 1 patient eventually being transferred to a ward for chronic patients within the hospital, which suggests that Sterkfontein Hospital functions largely as an acute psychiatric facility. There was a discrepancy of approximately 30% between the assessments of the certifying and ward doctors, probably as a result of differing uses of terminology. Not only are more community psychiatric services needed, but communication between psychiatry and the other medical disciplines should be improved.  相似文献   
140.
Antigenic characterization of urothelial cells cultured from normal adult ureter was performed. These cells were cultured using a simplified isolation and culture technique and a commercially available serum-free medium. The cells growing in these cultures had epithelioid morphology and normal quantities of DNA. The antigen expression on these cultured normal urothelial cells was evaluated using a panel of monoclonal antibodies: 5G6.4, AN43, URO-5, anti-keratin and anti-blood group antibodies, and 425 (anti-epidermal growth factor receptor). Lower levels of anti-A and AN43 binding on cultured cells were observed than are seen on urothelial cells in sections of normal ureter, while the binding of anti-blood group H, 5G6.4, and URO-5 was unchanged. Binding of anti-epidermal growth factor receptor antibody 425 was improved if the cells were grown in medium lacking epidermal growth factor. These results confirm the urothelial origin of these cultured urothelial cells but indicate that some antigenic differences between cultured normal urothelial cells and urothelial cells in situ in the normal ureter exist.  相似文献   
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