全文获取类型
收费全文 | 11584篇 |
免费 | 909篇 |
国内免费 | 53篇 |
专业分类
耳鼻咽喉 | 110篇 |
儿科学 | 615篇 |
妇产科学 | 305篇 |
基础医学 | 1745篇 |
口腔科学 | 240篇 |
临床医学 | 1060篇 |
内科学 | 2559篇 |
皮肤病学 | 130篇 |
神经病学 | 997篇 |
特种医学 | 488篇 |
外科学 | 1983篇 |
综合类 | 230篇 |
一般理论 | 3篇 |
预防医学 | 777篇 |
眼科学 | 221篇 |
药学 | 509篇 |
中国医学 | 11篇 |
肿瘤学 | 563篇 |
出版年
2021年 | 109篇 |
2019年 | 107篇 |
2018年 | 138篇 |
2017年 | 118篇 |
2016年 | 118篇 |
2015年 | 138篇 |
2014年 | 229篇 |
2013年 | 318篇 |
2012年 | 410篇 |
2011年 | 427篇 |
2010年 | 247篇 |
2009年 | 230篇 |
2008年 | 438篇 |
2007年 | 412篇 |
2006年 | 396篇 |
2005年 | 471篇 |
2004年 | 431篇 |
2003年 | 373篇 |
2002年 | 389篇 |
2001年 | 375篇 |
2000年 | 360篇 |
1999年 | 312篇 |
1998年 | 155篇 |
1997年 | 137篇 |
1996年 | 132篇 |
1995年 | 124篇 |
1992年 | 289篇 |
1991年 | 280篇 |
1990年 | 291篇 |
1989年 | 313篇 |
1988年 | 292篇 |
1987年 | 295篇 |
1986年 | 278篇 |
1985年 | 257篇 |
1984年 | 182篇 |
1983年 | 202篇 |
1982年 | 130篇 |
1981年 | 135篇 |
1980年 | 125篇 |
1979年 | 222篇 |
1978年 | 198篇 |
1977年 | 152篇 |
1976年 | 164篇 |
1975年 | 149篇 |
1974年 | 144篇 |
1973年 | 146篇 |
1972年 | 150篇 |
1971年 | 108篇 |
1970年 | 103篇 |
1969年 | 116篇 |
排序方式: 共有10000条查询结果,搜索用时 968 毫秒
191.
192.
193.
E H Kaplan 《Medical decision making》1999,19(2):207-213
This paper presents an implicit valuation of Israel's decision to exclude blood donations from Ethiopian immigrants. The approach adopts assumptions that deliberately overstate the public health effectiveness of this policy, for if such an analysis fails to justify exclusion on public health grounds, nothing will. Building on a recent (over)estimate of the number of infectious donations prevented by the ban, the analysis considers the cost of HIV-infectious donations entering the blood supply, the benefits of healthy donations, and the cost of needlessly screening blood that will be discarded without regard to the test result. The analysis also highlights the social costs of excluding donors on the basis of ethnicity. The possibility of downstream HIV transmission from transfusion recipients infected from contaminated blood is also considered. All such calculations are made in a manner that deliberately favors the exclusion decision. In spite of such a one-sided analysis, the author concludes that the exclusion policy is not justifiable on cost-benefit grounds if the social costs of exclusion exceed $218,000 per year, or $3.63 per Ethiopian immigrant annually. 相似文献
194.
A two-stage approach was used to analyze Problem 2 simulated data from Genetic Analysis Workshop 11. In the first stage, we tested for linkage with the Haseman-Elston test in SIBPAL. Markers that were significant in the first stage were followed up with two types of association tests. These association tests differ in the type of family information used: 1) parental transmissions to affected children or 2) differences in marker allele frequencies between affected and unaffected siblings. We also explored how the conclusions changed when different sampling strategies were used. Of particular interest was whether the entire data set should be used to test for both linkage and association or whether the data set should be halved to allow for replication of the initial association results. 相似文献
195.
196.
Objectives
To compare safety and efficacy of fascial versus vaginal wall slings in the management of women with intrinsic sphincter deficiency (ISD).Methods
The hospital and office records of 79 consecutive women with ISD were retrospectively analyzed from January 1991 to September 1995. There were 43 fascial slings (group A) and 36 vaginal wall slings (group B). Parameter of evaluation included efficacy based on postoperative presence of stress or urge incontinence and number of pads used, complications, and miscellaneous factors, including length of catheterization time, length of hospitalization, quantity of analgesics used, and loss of work days.Results
Baseline clinical and urodynamic data were the same for both groups. Pad use decreased from 6.9 to 0.6 for group A and from 5.7 to 0.3 for group B. Persistent stress and urge incontinence was present in 5% and 16% of group A patients and in 3% and 11 % of group B patients, respectively. Group A (89%) and group B (94%) patients were either very satisfied or satisfied with their surgical outcome. The operative time, hospital days, and days lost from work for group B patients (42.3 ± 13.4 minutes, 1.4 ± 0.9 days, 18.4 ±3.2 days, respectively) were significantly lower than for group A patients (84.2 ± 17.8 minutes, 3.7 ± 1.9 days, 28.4 ±7.8 days, respectively).Conclusions
Both fascial and vaginal wall slings are effective in treating women with ISD. However, the use of vaginal wall slings resulted in significantly shorter hospital stay, decreased catheterization time, decreased use of analgesics, and decreased loss of days of work compared with fascial slings. Therefore, the vaginal wall sling should be the preferred surgical method of treating intrinsic sphincter deficiency. 相似文献197.
198.
Treatment of this pathophysiologically poorly understood disease is controversial. Despite this uncertainty, the goals of management of the patient with preeclampsia and eclampsia are diagnosis, stabilization, and delivery of the baby. Stabilization refers to both mother and fetus and should include the prevention of eclampsia or the recurrence of eclamptic seizures. There are empiric data supporting the use of magnesium sulfate for the management of preeclampsia and eclampsia in North America, but there are few data to support its efficacy as a classic anticonvulsant. Until controlled trials are completed, we suggest that magnesium sulfate continue to be used in preeclampsia, with the addition of established anticonvulsant medications when eclampsia occurs. Data on established antiepileptic drugs such as diazepam and phenytoin support their use in treating patients with eclamptic seizures. As stated in an earlier review, "in treating preeclampsia, magnesium sulfate therapy may have a role and may moderate factors leading to eclampsia. Whether magnesium sulfate therapy may have some as yet unproved effect on epileptogenic foci or seizure propagation is not the important issue for the physician caring for the eclamptic patient. Until adequately designed therapeutic trials are available, it is our opinion that treatment should be based on the use of anticonvulsant drugs of established efficacy in seizure control and prophylaxis (p. 1363)." 相似文献
199.
Occult fracture patterns of the knee associated with anterior cruciate ligament tears: assessment with MR imaging. 总被引:27,自引:0,他引:27
One hundred consecutive magnetic resonance (MR) images of the knee in patients with acute complete anterior cruciate ligament (ACL) tears were reviewed to evaluate the prevalence and patterns of associated occult fractures. Eighty-nine occult fractures were identified in 56 knees. All occult fractures were in the posterior aspect of the lateral tibial plateau. Of these, occult fractures were isolated in 24 cases (43%) and were in combination with fractures in the middle aspect of the lateral femoral condyle in 26 (46%), with fractures in the posterior aspect of the medial tibial plateau in four (7%), and with fractures involving all three areas in one (2%). Disruption of the ACL under valgus stress leads to anterior translation of the tibia and relative external rotation of the femur. This allows impaction of the posterior portion of the lateral tibial plateau against the middle of the lateral femoral condyle and accounts for the unique pattern of occult fractures associated with ACL tears. An occult fracture of the posterior lateral tibial plateau with or without an associated fracture in the lateral femoral condyle ("kissing contusion") is a relatively frequent finding in acute ACL tears and, when present, is highly suggestive of such an associated tear. 相似文献
200.
A 30-year-old patient with tardive dystonia, who had failed to respond to cessation of neuroleptics, placebo, diazepam, biperiden, propranolol, and clonidine, had an impressive response to courses of electroconvulsive therapy (ECT) on three successive trials. 相似文献