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991.
C. Mohan A. K. Gupta R. K. Saxena 《Indian journal of otolaryngology and head and neck surgery》1993,45(4):207-208
Embryonal Rhabdomyosarcoma is relatively uncommon of the Paediatric Tumours. In this paper a rare case of Embryonal Rhabdomyosarcoma of the middle ear/mastoid is presented with relevant review of literature. 相似文献
992.
993.
Nimodipine-induced changes in the distribution of carotid blood flow and cardiac output in pentobarbitone-anaesthetized pigs. 总被引:3,自引:3,他引:0
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D. J. Duncker J. Heiligers E. J. Mylecharane P. R. Saxena P. D. Verdouw 《British journal of pharmacology》1986,89(1):35-46
In view of the claimed effectiveness of nimodipine in migraine and its possible selectivity for cerebral vessels, we investigated the effects of nimodipine in anaesthetized pigs on the fractionation of carotid arterial blood flow into non-nutrient (arteriovenous anastomoses; AVAs) and nutrient (capillary) parts, and on regional tissue blood flows and vascular conductances. Intracarotid infusions of nimodipine (0.05-1.25 microgram kg-1 min-1) redistributed carotid blood flow in favour of its nutrient compartment, particularly to the skeletal muscles and tongue. Vascular conductance in the non-nutrient (AVAs) compartment decreased (40%), most likely, as a result of 'steal' following profound (5.5 fold) arteriolar dilatation. Intravenous infusions of nimodipine (0.05-6.25 micrograms kg-1 min-1) caused hypotension, bradycardia, a decrease in conduction in the non-nutrient fraction, and an increase in conduction in the nutrient fraction (mostly in the skeletal muscles, but also in the gastrointestinal tract, cerebral hemispheres, heart and adrenals). Probably due to the hypotensive effect, only skeletal muscle blood flow increased. The nimodipine-induced increase in vascular conductance in the skeletal muscles showed regional variation; the effect was most pronounced in the cheek muscles, followed by the muscles of the chest, abdominal, trunk and gluteal regions. We conclude that: AVA flow seems to represent a 'reserve' perfusion which can be readily diverted to tissues in the case of increased metabolism and/or vasodilatation, though the overall response to nimodipine of carotid blood flow distribution qualitatively resembles that to some antimigraine drugs, the relevance of such acute effects in the prophylactic usefulness of nimodipine in migraine remains to be ascertained, and nimodipine lacks a selective cerebral vasodilator action in the anaesthetized pig. 相似文献
994.
In the present study an attempt has been made to observe the pathological alterations brought about in the intestine, liver, and kidney of lead-intoxicated rats. A short-term exposure to a sublethal dose of lead (44 mg/kg body wt/day) is seen to cause conspicuous degenerative changes in the three tissues. The intestinal mucosal epithelium is affected which leads to malabsorption, while in the kidney proximal tubular cells degenerate causing secretion of essential materials such as glucose, amino acids, etc., in the urine. 相似文献
995.
C Hedman AR Andersen PG Andersson NE Gilhus P Kangasniemi J-E Olsson E Strandman K Nestvold J Olesen 《Cephalalgia : an international journal of headache》1988,8(4):279-284
There is little information available concerning whether, and to what extent, migraine-prophylactic agents interfere with the symptoms of migraine attacks. The present study is a placebo-controlled, double-blind study concerning metoprolol in classic migraine. The data refer to the symptoms of single migraine attacks. During metoprolol treatment more attacks were characterized as mild (p = 0.002), and mean global rating (an integrated estimate of headache intensity and of other discomfort) was lower (4.2 versus 5.2, p = 0.003). The mean headache intensity per attack (1.97 versus 2.15) and the mean duration (5.5 versus 6.8 h) were not significantly different. Consumption of analgesics per attack was lower during metoprolol treatment (0.6 versus 1.1; p = 0.02). Attacks with associated symptoms accompanying the headache were fewer during metoprolol treatment (p = 0.014). Total visual and non-visual aura symptoms occurred with similar frequency, but scintillations and paraesthesia were more frequent during metoprolol treatment, whereas speech disturbances were less frequent. In spite of lower consumption of analgesics, the symptoms appeared milder during metoprolol than during placebo. The pattern of changes indicates that metoprolol exerts its action via the sympathetic nervous system; peripheral vasoconstriction is hardly the underlying mechanism of action. 相似文献
996.
Abstract
Session 10a Long-acting contraception 相似文献997.
Willem A. Bax Dicky Van Heuven-Nolsen Egbert Bos Maarten L. Simoons Pramod R. Saxena 《Naunyn-Schmiedeberg's archives of pharmacology》1992,345(5):500-508
Summary The receptors mediating the contractile effect of 5-hydroxytryptamine (5-HT) on the human isolated saphenous vein, obtained from 42 patients undergoing coronary bypass surgery, have been further characterized using a number of 5-HT-related drugs. The rank order of agonist potency was 5-carboxamidotryptamine (5-CT) 5-HT > methysergide sumatriptan -methyl-5-HT 5-methoxy-3-(1,2,3,6-tetrahydropyridin-4-yl)-1-Hindolesuccinate (RU 24969) 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane hydrochloride (DOI) > 2-methyl-5-HT > 8-hydroxy-2(di-n-propylamino)tetralin (8-OH-DPAT). Flesinoxan was inactive as an agonist. Ketanserin (1 mol/l) hardly affected sumatriptan-induced contractions but it caused a rightward shift of the upper part of the concentration-response curve of 5-HT and 5-CT. The same concentration of ketanserin caused a parallel rightward shift of the concentration-response curves of -methyl-5-HT and DOI with pKB values of 7. 1 and 7.1, respectively. The responses to sumatriptan were antagonized by methiothepin (0.1 mol/l), metergoline (0.1 and 1 mol/l), rauwolscine (1 mol/l) and cyanopindolol (1 mol/l); the calculated pKB values were 7.3, 6.9, 7.3, 6.7 and 6.5, respectively. Contractions to 5-HT were antagonized by methysergide (1 mol/l), methiothepin (0.1 mol/l; pKB = 7.1), ICS 205-930 (1 mol/l; pKB = 5.9) and flesinoxan (30 mol/l; pKB = 5.3). Remarkably, the contractions elicited by 2-methyl-5-HT were not attenuated by ICS 205-930, but were antagonized by methiothepin (0.1 mol/l) and, more markedly, by ketanserin (1 mol/l).There was a high correlation between the functional pD2 values of 5-HT1-like receptor agonists (5-CT, 5-HT, methysergide, sumatriptan, RU 24969 and 8-OH-DPAT) and their reported binding affinities for the 5-HT1D receptor in human or calf brain membranes. Such a correlation for the antagonism of sumatriptan-induced responses was less marked than for the agonists, but of the 5-HT1-like receptor subtypes it was the highest for the 5-HT1D receptor identified in human or calf brain membranes.In 3 patients, undergoing heart transplantation, saphenous vein which had previously functioned as a graft for 6–11 years, was dissected out from the heart. Though the contractions to potassium were significantly smaller in the grafted veins, the pD2 and Emax values (calculated as percentage of potassium-induced contractions) for 5-HT and sumatriptan were similar to those found in the veins obtained directly from the lower leg.It is concluded that contractions in the human isolated saphenous vein induced by 5-HT are mediated by 5-HT2 receptors as well as by a 5-HT1-like receptor resembling the 5-HT1D subtype found in brain membranes. It is also to be noted that 2-methyl-5-HT, considered selective for the 5-HT3 receptor, contracts the saphenous vein mainly via 5-HT2 receptors.This study was supported by the Netherlands Heart Foundation, grant 89.252
Send offprint requests to W. A. Bax at the above address 相似文献
998.
Brandon M. Kistler Linda W. Moore Debbie Benner Annabel Biruete Mona Boaz Giuliano Brunori Jing Chen Christiane Drechsler Fitsum Guebre-Egziabher Mary Kay Hensley Kunitoshi Iseki Csaba P. Kovesdy Martin K. Kuhlmann Anita Saxena Pieter ter Wee Amanda Brown-Tortorici Giacomo Garibotto S. Russ Price Kamyar Kalantar-Zadeh 《Journal of renal nutrition》2021,31(2):116-120.e1
999.
Osteochondral defects, often caused by traumatic injuries, are focal areas of articular damage resulting in joint pain and stiffness ultimately leading to degenerative joint disease. This has not been well studied in the first metatarsal head, but is an often encountered problem in the active population in other joints. In this study, we prospectively evaluated the results of 12 patients who received autogenous bone grafting for repair of osteochondral defects of the first metatarsal head. Clinical outcomes were evaluated by the visual analog scale for pain and the Roles and Maudsley (RM) score. Between the years of 2009 and 2016, 12 patients received treatment for this particular surgical intervention and their outcomes were measured. The patients’ average age was 43.5 ± 10.6 years and were followed from 52.3 ± 26.7 months postoperatively. Average return to activity was 4.7 ± 1.1 months. The average preoperative RM score was 4.0 ± 0.0 and postoperative RM score was 1.4 ± 0.7 (p = .0001). The encouraging outcomes of this study suggest that autogenous bone grafting for osteochondral defects of the first metatarsal head is an effective treatment to help restore the function of the first metatarsophalangeal joint. 相似文献
1000.
Sugandha Saxena Abhilasha Purohit Michelle L. Varney Yuri Hayashi Rakesh K. Singh 《BMC cancer》2018,18(1):1283