全文获取类型
收费全文 | 1802831篇 |
免费 | 140970篇 |
国内免费 | 2960篇 |
专业分类
耳鼻咽喉 | 24242篇 |
儿科学 | 59188篇 |
妇产科学 | 50412篇 |
基础医学 | 256684篇 |
口腔科学 | 51961篇 |
临床医学 | 157372篇 |
内科学 | 358381篇 |
皮肤病学 | 39504篇 |
神经病学 | 148129篇 |
特种医学 | 70450篇 |
外国民族医学 | 558篇 |
外科学 | 268220篇 |
综合类 | 40542篇 |
现状与发展 | 4篇 |
一般理论 | 598篇 |
预防医学 | 141676篇 |
眼科学 | 40459篇 |
药学 | 135539篇 |
3篇 | |
中国医学 | 3576篇 |
肿瘤学 | 99263篇 |
出版年
2018年 | 21399篇 |
2017年 | 16010篇 |
2016年 | 17236篇 |
2015年 | 19834篇 |
2014年 | 25736篇 |
2013年 | 39460篇 |
2012年 | 56863篇 |
2011年 | 58945篇 |
2010年 | 33392篇 |
2009年 | 30578篇 |
2008年 | 55206篇 |
2007年 | 58254篇 |
2006年 | 57957篇 |
2005年 | 56553篇 |
2004年 | 55122篇 |
2003年 | 52182篇 |
2002年 | 50763篇 |
2001年 | 80136篇 |
2000年 | 82936篇 |
1999年 | 70483篇 |
1998年 | 18459篇 |
1997年 | 16924篇 |
1996年 | 16881篇 |
1995年 | 16562篇 |
1994年 | 15522篇 |
1993年 | 14629篇 |
1992年 | 57779篇 |
1991年 | 55967篇 |
1990年 | 54618篇 |
1989年 | 52736篇 |
1988年 | 49091篇 |
1987年 | 48261篇 |
1986年 | 45911篇 |
1985年 | 44313篇 |
1984年 | 33119篇 |
1983年 | 28513篇 |
1982年 | 16676篇 |
1981年 | 14871篇 |
1979年 | 31400篇 |
1978年 | 21744篇 |
1977年 | 18389篇 |
1976年 | 17189篇 |
1975年 | 18206篇 |
1974年 | 22285篇 |
1973年 | 21454篇 |
1972年 | 19605篇 |
1971年 | 18492篇 |
1970年 | 16970篇 |
1969年 | 15964篇 |
1968年 | 14593篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
A. Nakao H. Toyokawa A. Tsung M. A. Nalesnik D. B. Stolz J. Kohmoto A. Ikeda K. Tomiyama T. Harada T. Takahashi R. Yang M. P. Fink K. Morita A. M. K. Choi N. Murase 《American journal of transplantation》2006,6(10):2243-2255
Carbon monoxide (CO), a byproduct of heme catalysis, was shown to have potent cytoprotective and anti-inflammatory effects. In vivo recipient CO inhalation at low concentrations prevented ischemia/reperfusion (I/R) injury associated with small intestinal transplantation (SITx). This study examined whether ex vivo delivery of CO in University of Wisconsin (UW) solution could ameliorate intestinal I/R injury. Orthotopic syngenic SITx was performed in Lewis rats after 6 h cold preservation in control UW or UW that was bubbled with CO gas (0.1-5%) (CO-UW). Recipient survival with intestinal grafts preserved in 5%, but not 0.1%, CO-UW improved to 86.7% (13/15) from 53% (9/17) with control UW. At 3 h after SITx, grafts stored in 5% CO-UW showed improved intestinal barrier function, less mucosal denudation and reduced inflammatory mediator upregulation compared to those in control UW. Preservation in CO-UW associated with reduced vascular resistance (end preservation), increased graft cyclic guanosine monophosphate levels (1 h), and improved graft blood flow (1 h). Protective effects of CO-UW were reversed by ODQ, an inhibitor of soluble guanylyl cyclase. In vitro culture experiment also showed better preservation of vascular endothelial cells with CO-UW. The study suggests that ex vivo CO delivery into UW solution would be a simple and innovative therapeutic strategy to prevent transplant-induced I/R injury. 相似文献
92.
The absence of the temporary incisors could be to a genetic illness or to some multiple premature extractions. These extractions are the aftermaths of the carious lesions or some traumatisms underwent by the temporary incisors. Beyond measure the loss of the space, the premature loss some temporary incisors very often assign the relational development of the child and disturb its psychological development and the aesthetic function. Across some cases clinics, the authors show that the replacement of the temporary incisors is the therapeutic ideal solution. Indeed, the child prosthesis, replacing the temporary absent incisors, solves the psychological, aesthetic and relational problems of the child. 相似文献
93.
Victor Aboyans Louis Labrousse Philippe Lacroix Jér?me Guilloux Seifeddine Sekkal Alexandre Le Guyader Elisabeth Cornu Marc Laskar 《European journal of cardio-thoracic surgery》2006,30(2):300-304
BACKGROUND: Despite major improvement in surgical techniques and intensive care management, stroke remains one of the most devastating complications of coronary artery bypass grafting (CABG). We aimed to determine factors predicting the occurrence of stroke during CABG. A special interest was focused on preoperative therapies. METHODS: We prospectively enrolled 810 consecutive candidates for CABG alone in a specific database, including all pre- and perioperative data (history, clinical, therapeutic, cardiac catheterization, surgical and intensive care data). Univariate tests and then multiple logistic regression analysis were used to determine independent predictive factors. RESULTS: During the first postoperative month, stroke occurred in 11 cases and transient ischemic attack (TIA) in 4 additive cases (cumulative rate: 1.85%). After the multivariate analysis, the following factors remained significant (p<0.05) in the predictive model, with corresponding odds ratios between brackets: redo cardiac surgery (7.45), unstable cardiac status (4.74), past history of cerebrovascular disease (4.14), past history of peripheral arterial disease (3.55), whereas the presence of preoperative statins was protective (0.24, 95% IC: 0.07-0.78). The addition of perioperative data (aortic calcification, postoperative arrhythmia, on/off-pump surgery) did not change the final predictive model. CONCLUSION: To our knowledge, this is the first real-world observational report highlighting the interest of statins for the prevention of stroke in the very special situation of CABG. Even though according to randomized trials coronary patients have a benefit from these drugs, a special level of interest should be directed towards those presenting the above-mentioned risk factors. 相似文献
94.
Gazzaruso C. Bruno R. Pujia A. 《世界核心医学期刊文摘》2006,2(8):54-54
背景:针对糖尿病患者Lp(a)水平和冠状动脉疾病(CAD)严重程度之间关系的研究较少并且结论有争议。另外,目前尚无关于apo(a)多态性与上述疾病关系的研究。本研究旨在探讨大样本2型糖尿病患者中冠状动脉粥样硬化的程度与Lp(a)水平及apo(a)多态性的相关性。方法:连续选取227例2型糖 相似文献
95.
96.
O Schouten J H H van Laanen E Boersma R Vidakovic H H H Feringa M Dunkelgrün J J Bax J Koning H van Urk D Poldermans 《European journal of vascular and endovascular surgery》2006,32(1):21-26
OBJECTIVE: To evaluate the effect of statins on aneurysm growth in a group of consecutive patients under surveillance for infrarenal aortic aneurysms (AAA). MATERIALS AND METHODS: All patients (59 statin users, 91 non-users) under surveillance between January 2002 and August 2005 with a follow-up for aneurysm growth of at least 12 months and a minimum of three diameter evaluations were retrospectively included in the analysis. Multiple regression analysis, weighted with the number of observations, was performed to test the influence of statins on AAA growth rate. RESULTS: During a median period of 3.1 (1.1-13.1) years the overall mean aneurysm growth rate was 2.95+/-2.8 mm/year. Statin users had a 1.16 mm/year lower AAA growth rate compared to non-users (95% CI 0.33-1.99 mm/year). Increased age was associated with a slower growth (-0.09 mm/year per year, p = 0.003). Female gender (+1.82 mm/year, p = 0.008) and aneurysm diameter (+0.06 mm/year per mm, p = 0.049) were associated with increased AAA growth. The use of non-steroidal anti-inflammatory drugs, chronic lung disease, or other cardiovascular risk factors were not independently associated with AAA growth. CONCLUSIONS: Statins appear to be associated with attenuation of AAA growth, irrespective of other known factors influencing aneurysm growth. 相似文献
97.
98.
99.
D Yinon L Lowenstein S Suraya R Beloosesky O Zmora A Malhotra G Pillar 《The European respiratory journal》2006,27(2):328-333
Pre-eclamptic toxaemia (PET) may be associated with both endothelial dysfunction (ED) and sleep-disordered breathing (SDB). It was hypothesised that females with PET would demonstrate both SDB and ED, and that a correlation between these two would suggest a potential causative association. A total of 17 females with PET and 25 matched females with uncomplicated pregnancy were studied. They underwent a nocturnal ambulatory sleep study (using Watch_PAT100) and noninvasive evaluation of endothelial function utilising the reactive hyperaemia test (using Endo_PAT 2000). A higher ratio of post- to pre-occlusion pulse-wave amplitude (endothelial function index (EFI)) indicated better endothelial function. Females with PET had a significantly higher respiratory disturbance index (RDI) and lower EFI than controls (18.4+/-8.4 versus 8.3+/-1.3.h(-1), and 1.5+/-0.1 versus 1.8+/-0.1, respectively). Blood pressure significantly correlated with RDI and with EFI. EFI tended to correlate with RDI. In conclusion, these results suggest that both sleep-disordered breathing and endothelial dysfunction are more likely to occur in females with pre-eclamptic toxaemia than in females with uncomplicated pregnancies. The current authors speculate that respiratory disturbances contribute to the functional abnormality of the blood vessels seen in females with pre-eclamptic toxaemia, although causality cannot be determined based on this study. 相似文献
100.
K P Sylvester S R Desai A U Wells D M Hansell M Awogbade S L Thein A Greenough 《The European respiratory journal》2006,28(4):832-838
The aim of this study was to determine whether patients with sickle cell disease (SCD) in steady state had pulmonary abnormalities seen on high-resolution computed tomography (HRCT) and whether any abnormalities correlated with contemporaneously diagnosed lung function abnormalities. A subsidiary question was whether the results of a noninvasive measure of haemolysis (end-tidal carbon monoxide (ETCO) levels) correlated with pulmonary function abnormalities. Thirty three patients with SCD, median (range) age 36 yrs (17-67 yrs) were examined. The degree of lobar volume loss and ground-glass opacification and prominence of central vessels on HRCT were quantitatively assessed. Pulmonary function was assessed by measurements of lung volumes, spirometry, gas transfer and oxygen saturation. ETCO levels were measured using an end-tidal CO monitor. Forced expiratory volume in one second (FEV1), forced vital capacity and total lung capacity significantly correlated with HRCT findings, particularly lobar volume loss. ETCO levels significantly negatively correlated with FEV1, vital capacity measured using a plethysmograph, specific airway conductance and arterial oxygen saturation measured by pulse oxymetry. In conclusion, the present results suggest that high-resolution computed tomography noninvasive assessment of haemolysis might be useful to identify sickle cell disease patients with respiratory function impairment. 相似文献