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   19843篇
  免费   2038篇
  国内免费   50篇
耳鼻咽喉   265篇
儿科学   757篇
妇产科学   547篇
基础医学   2831篇
口腔科学   637篇
临床医学   2446篇
内科学   3655篇
皮肤病学   345篇
神经病学   1691篇
特种医学   982篇
外科学   2341篇
综合类   514篇
一般理论   9篇
预防医学   2018篇
眼科学   283篇
药学   1545篇
中国医学   23篇
肿瘤学   1042篇
  2021年   291篇
  2020年   175篇
  2019年   293篇
  2018年   358篇
  2017年   271篇
  2016年   292篇
  2015年   322篇
  2014年   451篇
  2013年   634篇
  2012年   794篇
  2011年   827篇
  2010年   558篇
  2009年   466篇
  2008年   842篇
  2007年   847篇
  2006年   874篇
  2005年   738篇
  2004年   719篇
  2003年   668篇
  2002年   674篇
  2001年   637篇
  2000年   664篇
  1999年   543篇
  1998年   314篇
  1997年   265篇
  1996年   295篇
  1995年   254篇
  1994年   220篇
  1993年   257篇
  1992年   468篇
  1991年   438篇
  1990年   442篇
  1989年   479篇
  1988年   469篇
  1987年   368篇
  1986年   387篇
  1985年   422篇
  1984年   275篇
  1983年   226篇
  1982年   173篇
  1981年   174篇
  1979年   214篇
  1978年   192篇
  1977年   215篇
  1976年   182篇
  1975年   171篇
  1974年   172篇
  1973年   181篇
  1972年   169篇
  1971年   163篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
101.
Absorbable staples in continent ileal urinary pouch   总被引:1,自引:0,他引:1  
Continent ileal urinary reservoirs were created in dogs to study absorbable surgical staples. Within each pouch, certain controlled observations were possible. The staples and chemically similar polyglactin absorbable sutures caused almost identical tissue reactions. The staples outlasted the sutures, probably because of greater size. Inverted and everted staple closures worked equally well. It appears feasible to consider clinical urinary diversion with absorbable staples, a time-saving method.  相似文献   
102.
Fungal keratitis in contact lens wearers   总被引:8,自引:0,他引:8  
In a retrospective review from 1972 through 1987 of patients with microbial keratitis, fungal infection occurred in four (4%) of 90 cosmetic or aphakic contact lens wearers and in four (27%) of 15 patients using a therapeutic soft contact lens. Predisposing factors included improper lens care by the refractive lens wearers and a chronic epithelial defect with topical corticosteroid use among the therapeutic lens wearers. The responsible organisms in the refractive lens group were Fusarium solani (two patients) and Cephalosporium and Paecilomyces (one patient each), and in the therapeutic lens group Candida (three patients) and Aspergillus (one patient). Filamentous fungi were more likely to be associated with cosmetic or aphakic lens wear, whereas yeasts were more frequently found with therapeutic lens use.  相似文献   
103.
Pelvic allograft. A case report with a follow-up evaluation of 5.5 years   总被引:5,自引:0,他引:5  
A 23-year-old man with a large chondrosarcoma of the right bony pelvis was successfully treated by limb-saving internal hemipelvectomy and anatomic reconstruction of the pelvis by a pelvic osteoarticular allograft including the acetabulum. Optimum anatomic fit was achieved at the hip joint as well as at the iliac and pubic host-graft junctions, which were fixed with plates and screws. This reconstruction restored stability, leg length, hip motion, and cosmesis. Five and one-half years postoperatively, the patient remained asymptomatic with good functional and roentgenographic results.  相似文献   
104.
EDITORIAL COMMENT: We accepted this case report for publication not only because of its rare anecdotal interest, which is considerable, but also since it will warn readers that rectal bleeding in pregnancy may result from an abdominal pregnancy. It is strange that the ultrasonograph seems not to have identified the calcification as a fetus although we are not told that the latter was macerated or misshapen. The editor has never seen or heard of an ectopic pregnancy causing rectal erosion and bleeding although he has reported a primary abdominal pregnancy in which the placenta was implanted on the peritoneum of the pouch of Douglas posteriorly (A); this woman presented at 23 weeks' gestation when retroplacental haemorrhage resulted in a haematoma that bulged into the vagina causing acute urinary retention. One wonders why the placenta did not erode the anterior rectal wall in this more advanced case of primary placental implantment in the pouch of Douglas.
Summary: A rare case of abdominal pregnancy, causing massive rectal bleeding due to invasion of the rectal wall by the placenta, is reported.  相似文献   
105.
SUMMARY In order to assess the reliability of drug information supplied by day-stay cases, 85 consecutive patients were interviewed. A comparison of the interview answers with the details previously volunteered during the admission procedure showed an increase of 80% in the information given by the patient. While the detailed interviewing technique is time-consuming and may not be infallible, this substantial increase in information highlights problems in the current routine.  相似文献   
106.
107.
M H Robinson  M W Gear 《Gut》1991,32(9):1076-1078
A new technique for the management of upper and mid-oesophageal benign strictures is reported. A deflated oesophageal balloon catheter coated with steroid paste is passed by the patient through the stricture, the balloon is inflated and then withdrawn. This technique can be used for both strictures caused by tablet or corrosive damage that recur rapidly and where stricturing is the result of a chronic disease not amenable to medical or surgical treatments. Three patients in who this technique has been used with satisfactory patient tolerance and compliance and good relief of symptoms are reported.  相似文献   
108.
Gradient-recalled echo magnetic resonance imaging (GRE MRI), which gives information on blood flow and oxygenation changes (Robinson SP, Howe FA, Griffiths JR 1995, Int J Radiat Oncol Biol Phys 33: 855), was used to observe the responses of six rodent tumour models to carbogen breathing. In one transplanted rat tumour, the Morris hepatoma 9618a, and a chemically induced rat tumour, the MNU-induced mammary adenocarcinoma, there were marked image intensity increases, similar to those previously observed in the rat GH3 prolactinoma. In contrast, the rat Walker carcinosarcoma showed no response. In two mouse tumours, the RIF-1 fibrosarcoma and the human xenograft HT29, carbogen breathing induced a transient fall in signal intensity that reversed spontaneously within a few minutes. The rat GH3 prolactinoma was xenografted into nude mice, and an increase in image intensity was found in response to carbogen, suggesting that any effects that carbogen may have had on the host were not significant determinants of the tumour response. The increases in GRE image intensity of the MNU, H9618a and GH3 tumours during carbogen breathing are consistent with increases in tumour oxygenation and blood flow, whereas the responses of the RIF-1 and HT29 tumours may be the result of a transient steal effect followed by homeostatic correction.  相似文献   
109.
110.
Labeling of human sarcoma-associated murine monoclonal antibody (MAb) 23H7 with 67Ga and 111In by the bifunctional ligand method is reported. 67Ga was chelated to the MAb via desferrioxamine B and 111In via the cyclic anhydride of DTPA. Higher specific activity was obtained with 67Ga (4-5 microCi/micrograms) as compared with 111In (2 microCi/micrograms). The binding capacity of the MAb was confirmed by repeated indirect immuno-fluorescence assays performed before and after labeling. A fast blood clearance was observed: 33% recovered dose (R.D.) blood level 3 h post-injection as compared with 56% after injection of control polyclonal IgG. Preliminary results on chemically induced sarcoma bearing mice showed a relatively high tumor uptake of the labeled antibody.  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