全文获取类型
收费全文 | 6929篇 |
免费 | 692篇 |
国内免费 | 42篇 |
专业分类
耳鼻咽喉 | 115篇 |
儿科学 | 180篇 |
妇产科学 | 145篇 |
基础医学 | 838篇 |
口腔科学 | 308篇 |
临床医学 | 799篇 |
内科学 | 1335篇 |
皮肤病学 | 221篇 |
神经病学 | 475篇 |
特种医学 | 268篇 |
外科学 | 1196篇 |
综合类 | 202篇 |
一般理论 | 8篇 |
预防医学 | 704篇 |
眼科学 | 58篇 |
药学 | 499篇 |
中国医学 | 5篇 |
肿瘤学 | 307篇 |
出版年
2021年 | 102篇 |
2020年 | 64篇 |
2019年 | 120篇 |
2018年 | 107篇 |
2017年 | 74篇 |
2016年 | 108篇 |
2015年 | 117篇 |
2014年 | 152篇 |
2013年 | 240篇 |
2012年 | 304篇 |
2011年 | 291篇 |
2010年 | 179篇 |
2009年 | 157篇 |
2008年 | 245篇 |
2007年 | 257篇 |
2006年 | 315篇 |
2005年 | 288篇 |
2004年 | 231篇 |
2003年 | 268篇 |
2002年 | 242篇 |
2001年 | 212篇 |
2000年 | 231篇 |
1999年 | 206篇 |
1998年 | 102篇 |
1997年 | 97篇 |
1996年 | 89篇 |
1995年 | 73篇 |
1994年 | 71篇 |
1993年 | 75篇 |
1992年 | 169篇 |
1991年 | 165篇 |
1990年 | 150篇 |
1989年 | 175篇 |
1988年 | 155篇 |
1987年 | 134篇 |
1986年 | 136篇 |
1985年 | 149篇 |
1984年 | 115篇 |
1983年 | 72篇 |
1982年 | 63篇 |
1981年 | 69篇 |
1979年 | 85篇 |
1978年 | 79篇 |
1977年 | 65篇 |
1976年 | 63篇 |
1975年 | 51篇 |
1974年 | 62篇 |
1973年 | 76篇 |
1971年 | 56篇 |
1970年 | 56篇 |
排序方式: 共有7663条查询结果,搜索用时 15 毫秒
21.
22.
The natural history of spinal deformities in the cerebral palsy patient is different than that in the idiopathic patient. Consequently, the approach to the patient with cerebral palsy and the surgical decision-making are different from that in the idiopathic patient. The present article gives the UTMB approach to the treatment of the cerebral palsy patient and the unique considerations that must be taken into account when treating these patients. Specific references are made to the use of L-rod instrumentation to stabilize the spinal deformity in the cerebral palsy patient. 相似文献
23.
24.
Transplacental passage of mifepristone and its influence on maternal and fetal steroid concentrations in the second trimester of pregnancy 总被引:2,自引:0,他引:2
N C Hill M Selinger J Ferguson I Z MacKenzie 《Human reproduction (Oxford, England)》1991,6(3):458-462
The maternal and fetal endocrine effects of the maternal administration of the anti-progestin mifepristone in mid-pregnancy have been investigated. Mifepristone and the metabolite RU 42,633 were detected in the fetal circulation and in the amniotic fluid 4, 24 and 48 h after oral ingestion. Maximum fetal plasma concentrations of mifepristone occurred 4 h after treatment indicating rapid placental transfer of the drug. No significant changes in progesterone, cortisol, oestradiol or aldosterone concentrations were detected in the maternal circulation after mifepristone treatment. No significant changes occurred in the fetal progesterone, oestradiol or cortisol concentrations, but a significant increase in fetal aldosterone occurred 4 and 24 h after treatment. The significance of these results is discussed in relation to the possible therapeutic uses of mifepristone for inducing labour. 相似文献
25.
26.
Two hundred ninety-three carotid endarterectomies were performed with electroencephalogram (EEG) monitoring and without the use of a shunt. Two hundred sixteen patients had contralateral carotid stenosis of less than 70%; 45 had contralateral stenosis of 70 to 99%; and 32 had contralateral occlusion. There were six perioperative strokes (2.0%) and two deaths (0.7%). Major EEG changes were seen in 11 of the 77 patients (14.3%) with significant contralateral stenosis or occlusion versus 11 of the 216 patients (5.1%) in those without (P less than 0.025). The risk of immediate postoperative deficit was significantly higher in the subgroup with major EEG changes (4 of 22, 18.2%) than in those without such changes (5 of 271, 1.8%) (P less than 0.005). The risk in patients with less than 70% contralateral stenosis (7 of 216, 3.2%) was not significantly different from those with greater contralateral stenosis or occlusion (2 of 77, 2.6%). Carotid endarterectomy can be safely performed without a temporary shunt. Contralateral stenosis or occlusion alone does not confer increased risk. Major EEG changes are infrequent, but they identify a subgroup with significantly higher risk of intraoperative stroke. 相似文献
27.
28.
OBJECTIVE: Although VATS lobectomy has been demonstrated to be safe and effective, the technique is not widely practiced. This may, in part, reflect difficulty in acquiring appropriate skills. We have evaluated the effect of experience and training on surgical outcomes during the development and establishment of a VATS lobectomy programme. METHODS: Data were collected prospectively on 276 consecutive VATS lobectomies under the care of a single consultant as either the primary surgeon or supervising four trainees. The series was divided into cohorts of 46 patients. These comprised one trainee cohort and five sequential consultant cohorts. Statistical analysis utilised standard tests of significance. RESULTS: Increasing experience with the VATS lobectomy programme was associated with a significant reduction in operating time but intraoperative blood loss and postoperative stay were not influenced by increasing consultant surgical experience. Training was associated with a mean increase of 22 min operative time (p=0.0005) but no increase in intraoperative blood loss, morbidity, mortality or postoperative stay. The 46 trainee operative times were similar to the first 46 consultant cases. CONCLUSIONS: VATS lobectomy can be safely taught to trainee thoracic surgeons. However, in view of the limited number of centres undertaking VATS lobectomy, training should be coordinated at a national level to concentrate experience and improve uptake of this technique. 相似文献
29.
I R MacGregor J M Ferguson L F McLaughlin T Burnouf C V Prowse 《Thrombosis and haemostasis》1991,66(5):609-613
A non-stasis canine model of thrombogenicity has been used to evaluate batches of high purity factor IX concentrates from 4 manufacturers and a conventional prothrombin complex concentrate (PCC). Platelets, activated partial thromboplastin time (APTT), fibrinogen, fibrin(ogen) degradation products and fibrinopeptide A (FPA) were monitored before and after infusion of concentrate. Changes in FPA were found to be the most sensitive and reproducible indicator of thrombogenicity after infusion of batches of the PCC at doses of between 60 and 180 IU/kg, with a dose related delayed increase in FPA occurring. Total FPA generated after 100-120 IU/kg of 3 batches of PCC over the 3 h time course was 9-12 times that generated after albumin infusion. In contrast the amounts of FPA generated after 200 IU/kg of the 4 high purity factor IX products were in all cases similar to albumin infusion. It was noted that some batches of high purity concentrates had short NAPTTs indicating that current in vitro tests for potential thrombogenicity may be misleading in predicting the effects of these concentrates in vivo. 相似文献
30.
M Selinger I Z Mackenzie M D Gillmer S L Phipps J Ferguson 《British journal of obstetrics and gynaecology》1987,94(12):1218-1222
A double-blind, placebo controlled clinical trial was conducted to assess the clinical and physiological effects of 'epostane', a progesterone synthesis inhibitor, in mid-trimester prostaglandin termination of pregnancy. Mean peripheral progesterone levels had fallen by 74% after 72 h in the patients treated wtih epostane. The mean induction-abortion interval in the treatment group was 490 (SD 271) min, compared with 1432 (SD 640) min in the control group. Intrauterine pressure recording demonstrated increased sensitivity to prostaglandin E2 after epostane treatment but no change in oxytocin sensitivity. The clinical implications of facilitated induction of abortion are discussed. 相似文献