全文获取类型
收费全文 | 11288篇 |
免费 | 746篇 |
国内免费 | 50篇 |
专业分类
耳鼻咽喉 | 56篇 |
儿科学 | 342篇 |
妇产科学 | 191篇 |
基础医学 | 1597篇 |
口腔科学 | 200篇 |
临床医学 | 1060篇 |
内科学 | 2573篇 |
皮肤病学 | 215篇 |
神经病学 | 882篇 |
特种医学 | 474篇 |
外科学 | 1694篇 |
综合类 | 91篇 |
一般理论 | 4篇 |
预防医学 | 850篇 |
眼科学 | 345篇 |
药学 | 717篇 |
中国医学 | 12篇 |
肿瘤学 | 781篇 |
出版年
2023年 | 36篇 |
2022年 | 167篇 |
2021年 | 284篇 |
2020年 | 126篇 |
2019年 | 215篇 |
2018年 | 291篇 |
2017年 | 189篇 |
2016年 | 194篇 |
2015年 | 234篇 |
2014年 | 305篇 |
2013年 | 483篇 |
2012年 | 729篇 |
2011年 | 768篇 |
2010年 | 433篇 |
2009年 | 377篇 |
2008年 | 656篇 |
2007年 | 713篇 |
2006年 | 637篇 |
2005年 | 721篇 |
2004年 | 631篇 |
2003年 | 588篇 |
2002年 | 589篇 |
2001年 | 127篇 |
2000年 | 160篇 |
1999年 | 155篇 |
1998年 | 141篇 |
1997年 | 131篇 |
1996年 | 98篇 |
1995年 | 105篇 |
1994年 | 88篇 |
1993年 | 98篇 |
1992年 | 105篇 |
1991年 | 126篇 |
1990年 | 94篇 |
1989年 | 101篇 |
1988年 | 98篇 |
1987年 | 85篇 |
1986年 | 66篇 |
1985年 | 69篇 |
1984年 | 75篇 |
1983年 | 73篇 |
1982年 | 60篇 |
1981年 | 55篇 |
1980年 | 55篇 |
1979年 | 40篇 |
1978年 | 39篇 |
1977年 | 43篇 |
1974年 | 41篇 |
1973年 | 44篇 |
1972年 | 42篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
Thrombosis and thrombolysis in unstable angina 总被引:1,自引:0,他引:1
M L Brochier P Raynaud P Rioux B Charbonnier B Desveaux G Pacouret 《The American journal of cardiology》1991,68(7):105B-109B
Pathophysiology of unstable angina involves spasm, plaque rupture, activation of platelets, and coagulation. The incidence and frequency of intracoronary thrombus formation are presently under active assessment in order to establish the potential benefit of thrombolytic therapy. A preliminary study was conducted in patients admitted in our coronary care unit for unstable angina with typical clinical and electrocardiographic criteria and with early coronary angiogram. After exclusion of 4 patients with left main coronary stenosis or contraindications for thrombolysis, 16 patients received thrombolytic infusion and 14 underwent a second coronary angiogram. Seven patients had an intracoronary thrombus (6 nonocclusive, 1 occlusive) and at the second angiogram only 3 nonocclusive thrombi were modified (1 disappeared, 2 were reduced). Moreover, the quantitative Coronary Angiography Analysis System (CAAS) in the 11 cases suitable for analysis did not show any significant changes, especially in the Ambrose type IIB lesions. In-hospital clinical outcome was not influenced by thrombolytic therapy (5 ischemic recurrences, 1 fatal myocardial infarction, 4 emergency and 4 elective revascularization procedures). This short series is in agreement with the literature data. Only one third of patients with active unstable angina remains refractory to conventional therapy. The transient benefit of thrombolysis is limited to patients with demonstrated intracoronary thrombi. Clinical or angiographic improvement are not always in correlation and until now do not seem able to prevent short-term recurrences or the need for revascularization procedures. 相似文献
43.
44.
Pernes JM; Vitoux JF; Brenoit P; Raynaud A; Parola JL; Roth JP; Angel CY; Fiessinger JN; Roncato M; Gaux JC 《Radiology》1986,158(2):481-485
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs. 相似文献
45.
Clinical relevance of the host responses of periodontitis 总被引:1,自引:0,他引:1
46.
Radioiodinated tracers for the evaluation of dopamine receptors in the neonatal rat brain after hypoxic-ischemic injury 总被引:1,自引:0,他引:1
Amal Zouakia Sylvie Chalon Hank F. Kung Anne-Marie Dognon Elie Saliba Jean-Claude Besnard Denis Guilloteau 《European journal of nuclear medicine and molecular imaging》1994,21(6):488-492
In order to evaluate in vivo single-photon emission tomography (SPET) method of assessing cerebral function after hypoxic-ischemic injury in human neonates, we studied D1 and D2 dopamine receptors in a rat model. Seven-day-old rats underwent permanent unilateral common carotid ligation followed by exposure to 8% O2. Two weeks later, in brains with no visible loss of hemispheric volume, striatal dopaminergic receptors were studied, with [125I]TISCH and [1251]IBZM for the D1 and D2 dopamine receptors, respectively. Using [125I]TISCH, we observed no modifications of D1 receptors, but in contrast, ex vivo and in vitro autoradiographic experiments showed a 40% decrease in the striatal binding of [125I]IBZM on both the ipsilateral and the contralateral side to the carotid ligation. These alterations were detected with IBZM, a D2 dopamine receptor ligand usable for SPET imaging. Therefore, exploration of D2 receptors by SPET in human neonates suffering from perinatal hypoxia-ischemia may be valuable for the diagnosis and follow-up of cerebral function damages.
Correspondence to: D. Guilloteau 相似文献
47.
Changes in regional cerebral blood flow during brain maturation in children and adolescents. 总被引:25,自引:0,他引:25
C Chiron C Raynaud B Mazière M Zilbovicius L Laflamme M C Masure O Dulac M Bourguignon A Syrota 《Journal of nuclear medicine》1992,33(5):696-703
Regional cerebral blood flow (rCBF) was studied by SPECT using 133Xe in 42 children, aged 2 days to 19 years, considered as neurologically normal. rCBF was measured on cortical regions and on the cerebellum and thalamus. Curves for reference values and standard deviation were defined for each region. At birth, cortical rCBFs were lower than those for adults; after birth they increased until 5 or 6 yr of age to values 50%-85% higher than those for adults and thereafter decreased, reaching adult levels between 15 and 19 yr. Neonatal values of rCBF on cerebellum and thalamus were slightly higher than adult level, but not significantly; after age 1, they followed the common pattern for cortical curves. When rCBFs were expressed in percent global CBF, they were lower at birth than adult levels in the cortex, then increased and reached a plateau corresponding to the adult value before the second year of age. The time needed to reach normal adult values differed for each cortical region. The shortest time was found on the primary cortex and the longest on the associative cortex. Cognitive development of the child seems to be related to changes in blood flow of the corresponding brain regions. 相似文献
48.
49.
50.
Transjugular intrahepatic portosystemic shunt before abdominal surgery in cirrhotic patients: a retrospective, comparative study. 总被引:1,自引:0,他引:1
Evelyne Vinet Pierre Perreault Louis Bouchard Denis Bernard Ramses Wassef Carole Richard Richard Létourneau Gilles Pomier-Layrargues 《Journal canadien de gastroenterologie》2006,20(6):401-404
Surgery in cirrhotic patients is associated with high morbidity and mortality related to portal hypertension and liver insufficiency. Therefore, preoperative portal decompression is a logical approach to facilitate abdominal surgery and hopefully to improve postoperative survival. The present study evaluated the clinical outcomes of 18 patients (mean age 58 years) with cirrhosis (seven alcoholics and 11 nonalcoholics) who underwent transjugular intrahepatic portosystemic shunt (TIPS) placement before antrectomy (n=5), colectomy (n=10), small-bowel resection (n=1), pancreatectomy (n=1) and nephrectomy (n=1). TIPS was performed a mean (+/-SD) of 72+/-21 days before surgery and induced a marked mean decrease in portohepatic gradient from 21.4+/-3.9 mmHg to 8.4+/-3.4 mmHg. Cirrhotic patients (n=17) who underwent elective abdominal surgery without preoperative TIPS placement were used as the control group. Both groups were matched for age, etiology of cirrhosis, indications for surgery, type of surgery and coagulation parameters. The mean Pugh score was significantly higher in the TIPS group (7.7 versus 6.2). No significant differences were observed for operative blood loss, postoperative complications, duration of hospitalization and one-month (83% versus 88%) or one-year (54% versus 63%) cumulative survival rate. Analysis using the Cox proportional hazards model showed that neither TIPS placement nor preoperative Pugh score were independent predictors for survival. The present study suggests that preoperative TIPS placement does not improve postoperative evolution after abdominal surgery in cirrhotic patients with good or moderately impaired liver function. 相似文献