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91.
92.
Coronary angiographic morphology in myocardial infarction: a link between the pathogenesis of unstable angina and myocardial infarction 总被引:9,自引:0,他引:9
J A Ambrose S L Winters R R Arora J I Haft J Goldstein K P Rentrop R Gorlin V Fuster 《Journal of the American College of Cardiology》1985,6(6):1233-1238
It has previously been shown that analysis of coronary morphology can separate unstable from stable angina. An eccentric stenosis with a narrow neck or irregular borders, or both, is very common in patients who present with acute unstable angina, whereas it is rare in patients with stable angina. To extend these observations to myocardial infarction, the coronary morphology of 41 patients with acute or recent infarction and nontotally occluded infarct vessels was studied. For all patients, 27 (66%) of 41 infarct vessels contained this eccentric narrowing, whereas only 2 (11%) of 18 noninfarct vessels with narrowing of 50 to less than 100% had this lesion (p less than 0.001). In addition, a separate group of patients with acute myocardial infarction who underwent intracoronary streptokinase infusion were also analyzed in similar fashion. Fourteen (61%) of 23 infarct vessels contained this lesion after streptokinase infusion compared with 1 (9%) of 11 noninfarct vessels with narrowing of 50 to less than 100% (p less than 0.01). Therefore, an eccentric coronary stenosis with a narrow neck or irregular borders, or both, is the most common morphologic feature on angiography in both acute and recent infarction as well as unstable angina. This lesion probably represents either a disrupted atherosclerotic plaque or a partially occlusive or lysed thrombus, or both. The predominance of this morphology in both unstable angina and acute infarction suggests a possible link between these two conditions. Unstable angina and myocardial infarction may form a continuous spectrum with the clinical outcome dependent on the subsequent change in coronary supply relative to myocardial demand. 相似文献
93.
Extracellular matrix of cultured bovine aortic endothelial cells contains functionally active type 1 plasminogen activator inhibitor 总被引:17,自引:0,他引:17
The extracellular matrix (ECM) of cultured bovine aortic endothelial cells (BAEs) was analyzed by immunoblotting and reverse fibrin autography and shown to contain type 1 plasminogen activator inhibitor (PAI-1). Most PAI-1 in the ECM formed complexes with exogenously added tissue-type plasminogen activator (tPA), demonstrating that this PAI-1 was functionally active. The resulting tPA/PAI-1 complexes were recovered in the reaction solution, indicating that the PAI-1 in such complexes no longer bound to ECM. The PAI-1 could not be removed by incubating ECM in high salt (2 mol/L NaCl), sugars (1 mol/L galactose, 1 mol/L mannose), glycosaminoglycans (10 mmol/L heparin, 10 mmol/L dermatan sulfate), or epsilon-aminocaproic acid (0.1 mol/L). However, PAI-1 could be extracted from ECM by treatment with either arginine (0.5 mol/L) or potassium thiocyanate (2 mol/L), or by incubation under acidic conditions (pH 2.5). ECM depleted of PAI-1 by acid extraction was able to bind both the active and latent forms of PAI-1. In this instance, most of the bound PAI-1 did not form complexes with tPA, indicating that the latent form was not activated as a consequence of binding to ECM. Although the PAI-1 activity in conditioned medium decayed with a half-life (t 1/2) of less than 3 hours, the t 1/2 of ECM- associated PAI-1 was greater than 24 hours. These data suggest that PAI- 1 is produced by cultured BAEs in an active form and is then either released into the medium where it is rapidly inactivated or into the subendothelium where it binds to ECM. The specific binding of PAI-1 to ECM protects it from this inactivation. 相似文献
94.
Shivi Goel Jyoti Arora Vandana Mehta Mona Sharma Rajesh Kumar Suri Gayatri Rath 《World Journal of Clinical Cases》2015,3(1):85-88
The anatomical knowledge of arterial variations of lower limb is of utmost significance for the present day surgeons and interventional radiologists for minimizing complications during vascular reconstructive procedures, catheterization procedures and surgical intervention for embolism. Lateral Circumflex Femoral Artery(LCFA) isan important branch of Profunda Femoris artery and precise knowledge of its variations can be of great relevance during surgical and radiological procedures in femoral region. The present study reports a unique case of anomalous route taken by LCFA posterior to femoral nerve associated with a prominent muscular branch from Femoral artery mimicking the course of LCFA. Documentation of such variations is highly significant. It may serve as guideline for surgeons in reducing the incidence of postoperative complications where LCFA is used as a long vascular pedicle in anterolateral perforator thigh flap and in breast reconstruction after mastectomy. Ignorance of such variations can lead to fatal intraoperative haemorrhage and incapacitating sensory and motor deficit due to injury to femoral nerve branches which are closely related to these vessels. 相似文献
95.
Arunaloke Chakrabarti Prashant Sood Shivaprakash M. Rudramurthy Sharon Chen Harsimran Kaur Malini Capoor Deepinder Chhina Ratna Rao Vandana Kalwaje Eshwara Immaculata Xess Anupama J. Kindo P. Umabala Jayanthi Savio Atul Patel Ujjwayini Ray Sangeetha Mohan Ranganathan Iyer Jagdish Chander Anita Arora Raman Sardana Indranil Roy B. Appalaraju Ajanta Sharma Anjali Shetty Neelam Khanna Rungmei Marak Sanjay Biswas Shukla Das B. N. Harish Sangeeta Joshi Deepak Mendiratta 《Intensive care medicine》2015,41(2):285-295
96.
OBJECTIVE: Noninvasive blood pressure (BP) measurement is dependent on either auscultation or oscillometry. The Tensoval duo control device uses auscultatory and/or oscillometric technology to determine BP. We evaluated the accuracy of this device in adults according to the British Hypertension Society (BHS) protocol and the International Protocol of the European Hypertension Society. METHODS: Ethical approval was obtained and participants gave written informed consent. Eighty-five participants who fulfilled the protocol criteria were recruited. Nine sequential same arm measurements were taken from each participant by two trained observers, comparing the device to mercury sphygmomanometery. Data analysis was performed according to the respective protocol guidelines. RESULTS: The device achieved an A grade for both systolic and diastolic pressures with 68, 91 and 98% of systolic and 73, 91 and 98% of diastolic differences within the 相似文献
97.
Pelaez-Luna M Levy MJ Arora AS Baron TH Rajan E 《Gastrointestinal endoscopy》2008,67(6):974-5; discussion 975
98.
99.
Preeti Oswal Aayushi Arora Jolly Kaushal Gyandshwar Kumar Rao Sushil Kumar Ajai K. Singh Arun Kumar 《RSC advances》2019,9(39):22313
Two chalcogenated ligands L1 and L2 containing anthracene core and amine functionality have been synthesized. Both the ligands have been characterized using 1H and 13C{1H} NMR techniques. The structure of L1 has also been corroborated by single crystal X-ray diffraction. Application of L1 and L2 as stabilizers for palladium nano-particles (NPs) has been explored and six different types of NPs 1–6 have been prepared by varying the quantity of stabilizer. The nano-particles have been characterized by PXRD, EDX, and HRTEM techniques. The size of NPs has been found to be in the range of ∼1–2 nm, 2–3 nm, 4–6 nm, 1–2 nm, 1–2 nm and 3–5 nm for 1–6 respectively. The catalytic activities of 1–6 have been explored for Suzuki–Miyaura coupling of phenyl boronic acid with various aryl halides. These NPs showed good catalytic activity for various aryl chlorides/bromides at low catalyst loading (5 mg). Among 1–6, the highest activity has been observed for NPs 1, probably due to their relatively small size and high uniformity in the dispersion. The recyclability of the NPs upto 5 catalytic cycles is a distinct advantage.Monodispersed ultrasmall Pd nanoparticles synthesized utilizing bulky organochalcogen secondary amines as stabilizers and application in Suzuki coupling of aryl chlorides at low catalyst loading. 相似文献
100.