全文获取类型
收费全文 | 18190篇 |
免费 | 1725篇 |
国内免费 | 23篇 |
专业分类
耳鼻咽喉 | 238篇 |
儿科学 | 539篇 |
妇产科学 | 391篇 |
基础医学 | 2218篇 |
口腔科学 | 357篇 |
临床医学 | 2426篇 |
内科学 | 3499篇 |
皮肤病学 | 212篇 |
神经病学 | 1398篇 |
特种医学 | 731篇 |
外国民族医学 | 3篇 |
外科学 | 2412篇 |
综合类 | 477篇 |
一般理论 | 9篇 |
预防医学 | 1987篇 |
眼科学 | 601篇 |
药学 | 1491篇 |
中国医学 | 14篇 |
肿瘤学 | 935篇 |
出版年
2022年 | 112篇 |
2021年 | 316篇 |
2020年 | 206篇 |
2019年 | 290篇 |
2018年 | 324篇 |
2017年 | 206篇 |
2016年 | 288篇 |
2015年 | 301篇 |
2014年 | 408篇 |
2013年 | 585篇 |
2012年 | 799篇 |
2011年 | 868篇 |
2010年 | 474篇 |
2009年 | 407篇 |
2008年 | 733篇 |
2007年 | 826篇 |
2006年 | 848篇 |
2005年 | 779篇 |
2004年 | 769篇 |
2003年 | 695篇 |
2002年 | 646篇 |
2001年 | 576篇 |
2000年 | 599篇 |
1999年 | 527篇 |
1998年 | 222篇 |
1997年 | 197篇 |
1996年 | 196篇 |
1995年 | 189篇 |
1994年 | 166篇 |
1993年 | 151篇 |
1992年 | 411篇 |
1991年 | 415篇 |
1990年 | 385篇 |
1989年 | 398篇 |
1988年 | 347篇 |
1987年 | 332篇 |
1986年 | 331篇 |
1985年 | 317篇 |
1984年 | 262篇 |
1983年 | 224篇 |
1982年 | 150篇 |
1981年 | 119篇 |
1979年 | 193篇 |
1978年 | 168篇 |
1977年 | 142篇 |
1976年 | 128篇 |
1974年 | 161篇 |
1973年 | 145篇 |
1972年 | 129篇 |
1971年 | 116篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
A A Jackson A V Badaloo T Forrester J M Hibbert C Persaud 《The British journal of nutrition》1987,58(2):207-214
1. The evidence is accumulating to suggest that glycine, the simplest amino acid, is conditionally essential in man. Benzoic acid, by conjugation with glycine to form hippuric acid, is known to deplete the free glycine pool of the body. Glycine is one substrate for the enzyme glutathione synthase (EC 6.3.2.3) and in the inborn error of metabolism in which glutathione synthase function is defective, increased quantities of 5-oxoproline are excreted in the urine. 2. An oral dose of 4-10 g sodium benzoate was given to six normal adults to deplete the metabolic pool of glycine, and the urinary excretion of 5-oxoproline was followed for 6 h. In five of the six, a significant increase in the urinary 5-oxoproline was seen within 3 h. 3. These findings show that 5-oxoprolinuria can result from limited glycine availability, and may provide a useful test for assessing glycine sufficiency in a range of physiological and pathological states. 相似文献
12.
Hippocampal pathology in refractory temporal lobe epilepsy: T2-weighted signal change reflects dentate gliosis. 总被引:11,自引:0,他引:11
Regula S Briellmann Renate M Kalnins Samuel F Berkovic Graeme D Jackson 《Neurology》2002,58(2):265-271
BACKGROUND: The MR and pathologic features of hippocampal sclerosis (HS) are well described and include volume decrease and T2-weighted signal increase for MRI, and neuron cell loss and gliosis for pathology. OBJECTIVE: To confirm the established correlation between hippocampal volumes and neuron cell counts, and to study the still controversial association between signal change and gliosis. METHODS: The authors studied 44 patients (22 men and 22 women; mean age at surgery, 37 years) with refractory temporal lobe epilepsy. Quantitative assessment of hippocampal volumes and T2 relaxometry, and neuron and glial cell count in the region CA1 and molecular layer of the dentate gyrus was performed. The proportion of glial fibrillary acidic protein (GFAP)-positive glial cells (reactive astrocytes) was indicated. RESULTS: In a stepwise regression, the ipsilateral hippocampal volume was predicted best by the neuron cell count in the dentate gyrus (p = 0.005, r = 0.4). Hippocampal T2 time, however, was predicted best by the glial cell count in the dentate gyrus (p = 0.01, r = 0.4). None of the other cell counts contributed to either model. In the dentate, 31% of the glial cells were reactive astrocytes, whereas in CA1, 5% were reactive. CONCLUSION: The results confirmed the correlation between hippocampal volumes and neuron cell counts. T2-weighted signal increase in the hippocampus was mainly influenced by gliosis in the dentate gyrus, where a high proportion of glial cells show abnormal activity. This activity may reflect changes important in the development of hippocampal epileptogenicity. 相似文献
13.
14.
The incidence of AIDS among blacks and Hispanics 总被引:3,自引:0,他引:3
R Bakeman E McCray J R Lumb R E Jackson P N Whitley 《Journal of the National Medical Association》1987,79(9):921-928
Compared with whites, the acquired immune deficiency syndrome (AIDS) has affected blacks and Hispanics disproportionately. The cumulative incidence (CI) for black men was 2.6, and for Hispanic men 2.5, times the rate for white men. Intravenous (IV) needle use alone does not account for this difference. Not counting IV needle-using cases, the CIs for black and Hispanic men were 1.7 times the CI for white men. Although there were fewer cases in women than men, the white-to-minority disparity was greater for women. The CIs for black and Hispanic women were 12.2 and 8.5 times, respectively, the CI for white women. Prevention programs are urgently needed and should focus on risky behavior (IV needle sharing and receptive anal intercourse), not just risk groups. 相似文献
15.
16.
17.
18.
Background The incidence rate of incisional hernias after open surgery has been reported to be higher than that of port site hernias
after laparoscopic surgery. No studies have compared the costs for the health care system in treating those two types of hernia.
Methods A systematic review was conducted to obtain the baseline data, and a decision analysis model was created to simulate the occurrence
and recurrence of incisional and port site hernias.
Results The overall risk of having incisional hernias was eight-times higher than that of having port site hernias (7.4% vs 0.9%).
A cost savings of £93 per patient can be generated for the health care system in the UK. Similar results were obtained for
Germany, Italy and France.
Conclusions The additional treatment costs for incisional hernia should be taken into account when the costs of a surgery performed by
open approach are compared with by laparoscopy. 相似文献
19.
Andrew F Shorr William L Jackson Brendan M Weiss Lisa K Moores 《Blood coagulation & fibrinolysis》2007,18(4):309-316
Multiple options exist for the prevention of deep vein thrombosis (DVT) in medical inpatients. We sought to determine the cost-effectiveness of low-molecular-weight heparin (LMWH) relative to unfractionated heparin (UFH) for DVT prevention in this setting. We conducted a cost-effectiveness analysis from the perspective of a third-party payer employing a decision model and literature-based estimates for inputs. In the base-case analysis, LMWH had little impact on the rate of DVT. Despite higher acquisition costs, however, LMWHs resulted in net savings. Routine use of LMWH saves approximately US$89 per patient. The lower rate of heparin-induced thrombocytopenia (HIT) with LMWH accounted for this differential. Univariate sensitivity analysis revealed the model was moderately sensitive to the odds ratio of HIT with LMWH and the cost of HIT. Multivariate sensitivity analysis confirmed the LMWH approach dominated financially. 'Worst-case' scenario modeling, where LMWH actually increased the risk for DVT, had little effect on the rate of HIT, and was substantially more costly than UFH, still demonstrated that LMWHs were economically superior. Monte-Carlo simulation indicated the 95% confidence interval around the estimate for savings with LMWH ranged from US$7 to US$373. We conclude that, despite their higher cost, LMWHs for thromboprophylaxis in medical patients result in savings. 相似文献
20.
Justine Royle Rachel Williamson Mark Strachan Marie O’Donnell Simon Jackson Thanos Argryopoulos Alan McNeill 《British journal of medical & surgical urology》2009,2(5):204-207
Emphysematous pyelonephritis is a severe life-threatening infection which continues to carry significant morbidity and mortality. We present a case recently managed at our institution by laparoscopic nephrectomy. The patient survived, and in comparison to some of the more conventionally managed patients in the literature, made an extremely speedy recovery. We would advocate this option to be seriously considered when patients are suitable and appropriately trained surgeons are available. 相似文献