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71.
Five female patients and one male patient with solid and papillary epithelial neoplasms of the pancreas were examined with computed tomography (CT). The mean age of the patients was 27 years (range, 13-46 years). All cases showed well-encapsulated, round or lobulated masses consisting of both cystic and solid areas. Cystic portions showed CT numbers that suggested hemorrhagic necrosis. There were no internal septations within the masses. In three tumors located in the head of the pancreas, dilatation of the biliary tree was absent or minimal, although the masses were large. Two tumors contained calcifications. One tumor demonstrated metastatic deposits in liver and lymph nodes. Metastatic masses appeared similar to the primary pancreatic mass. Solid and papillary neoplasm of the pancreas should be the primary diagnostic consideration when characteristic CT findings are detected in a young female patient. 相似文献
72.
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74.
A Tajiri T Okamoto T Otsu H Choi S Tang S Mizoguchi F Yanagi Y Sakanashi K Gotoh H Matsumura 《Masui. The Japanese journal of anesthesiology》1992,41(11):1788-1792
A 47-y-o man had been suffering from cardiac failure due to refractory ventricular tachycardia (VT) after myocardial infarction. He underwent resection of the left ventricular aneurysm and cryocoagulation of the arrhythmogenic foci. On the 2nd post-operative day, VT often recurred in spite of repeated cardioversion and drug therapy, and threatened his life, even under IABP. Therefore, a veno-arterial bypass route was made and extracorporeal lung and heart assist, ECLHA, was started with a heparin bonded Maxima lung on the following day. Even under ECLHA, VT continued to recur. Cryocoagulation of the VT foci was tried again, without immediate success. A record high dose of beta-blockers, given under the circulatory support by ECLHA, stopped VT on the following day. The patient was weaned from the ECLHA circuit 12 days after the first operation, then from IABP on the 14th day. During the 10 day course of surgeries and ECLHA, the patient had almost 100 defibrillations. But for ECLHA, we may say that the patient couldn't have survived two open heart surgeries, administration of a great amount of beta-blockers, and repeated cardiac arrest without neurological sequelae. 相似文献
75.
O H Choi W L Padgett J W Daly 《The Journal of pharmacology and experimental therapeutics》1992,260(1):369-375
Two amphiphilic peptides from hymenopterid insects, melittin and mastoparan, stimulate secretion in a variety of cell types. In PC12 cells, both peptides stimulate calcium influx with melittin some 20-fold more potently than mastoparan. Melittin stimulates both breakdown of phosphoinositides (Pl) by phospholipase C to yield inositol phosphates and hydrolysis of phospholipids by phospholipase A2 to release arachidonic acid (AA). Mastoparan stimulates Pl breakdown, but has no effect on AA release. Maximal stimulation of Pl breakdown occurs at 1 to 2.5 micrograms/ml melittin and 30 micrograms/ml mastoparan, whereas maximal stimulation of AA release occurs at 2 to 5 micrograms/ml melittin. Organic calcium channel blockers (nifedipine, verapamil, diltiazem) have little or no effect on responses to the peptides. The influx of calcium elicited by melittin or mastoparan is completely or nearly completely blocked by inorganic calcium channel blockers (Co++, Mn++, Cd++). Mn++ and Cd++ inhibit melittin-induced Pl breakdown and AA release and mastoparan-induced Pl breakdown. Co++ has no effect on melittin-induced Pl breakdown and potentiates mastoparan-induced Pl breakdown. Pertussis toxin has no effect on the Pl breakdown induced by either peptide. The responses to melittin and mastoparan in PC12 cells are compared to those reported for maitotoxin. 相似文献
76.
A case of mycotic aneurysm of the intracavernous carotid artery is reported and the literature is reviewed on this uncommon entity. Nineteen cases have been reported, most often occurring in the clinical setting of meningitis. Management recommendations include angiographic confirmation of aneurysm and follow-up with magnetic resonance imaging during antibiotic therapy. Evidence of aneurysm enlargement is an indication for endovascular trapping of the aneurysm or carotid occlusion. 相似文献
77.
Tracy W. Harachi Yoonsun Choi Robert D. Abbott Richard F. Catalano Siri L. Bliesner 《Prevention science》2006,7(4):359-368
While there is growing awareness for the need to examine the etiology of problem behaviors across cultural, racial, socioeconomic, and gender groups, much research tends to assume that constructs are equivalent and that the measures developed within one group equally assess constructs across groups. The meaning of constructs, however, may differ across groups or, if similar in meaning, measures developed for a given construct in one particular group may not be assessing the same construct or may not be assessing the construct in the same manner in other groups. The aims of this paper were to demonstrate a process of testing several forms of equivalence including conceptual, functional, item, and scalar using different methods. Data were from the Cross-Cultural Families Project, a study examining factors that promote the healthy development and adjustment of children among immigrant Cambodian and Vietnamese families. The process described in this paper can be implemented in other prevention studies interested in diverse groups. Demonstrating equivalence of constructs and measures prior to group comparisons is necessary in order to lend support of our interpretation of issues such as ethnic group differences and similarities. 相似文献
78.
79.
D A Schwartz R T Bryan K O Hewan-Lowe G S Visvesvara R Weber A Cali P Angritt 《Archives of pathology & laboratory medicine》1992,116(6):660-668
Microsporidia are obligate intracellular protozoal parasites that infect a variety of cell types in a broad range of invertebrates and vertebrates. They have recently come to medical attention due to the increased frequency with which members of two microsporidian genera, Enterocytozoon and Encephalitozoon, are being diagnosed in patients with the acquired immunodeficiency syndrome (AIDS). The majority of published reports of human microsporidiosis describe Enterocytozoon infection of small intestinal enterocytes. In addition, a growing number of AIDS patients have been identified with infection due to the two species of Encephalitozoon-Encephalitozoon cuniculi and Encephalitozoon hellem, observed in conjunctival, corneal, and, recently, sinonasal tissues. However, there are scant data regarding the systemic pathology and epidemiology of these infections. This article describes a patient with AIDS who died with systemic Encephalitozoon infection. The etiologic microsporidian was found to be E hellem by using antemortem biochemical and antigenic analyses. A complete autopsy, the first to be reported in a patient with this infection, revealed organisms in the eyes, urinary tract, and respiratory tract. A surprising observation was the occurrence of numerous organisms within the lining epithelium of almost the entire length of the tracheobronchial tree, suggestive of respiratory acquisition. Detailed light and electron microscopic findings and the biological and diagnostic features of microsporidiosis are discussed. 相似文献
80.
Kolb Bryan; Buhrmann Kristin; McDonald Robert; Sutherland Robert J. 《Cerebral cortex (New York, N.Y. : 1991)》1994,4(6):664-680
Rats with lesions of the medial prefrontal, posterior parietal,or posterior temporal cortex were tested in five spatial navigationtasks, which varied in egocentric or allocentric demands, avisual discrimination task, and two delayed nonmatching-to-sampletasks. Rats with prefrontal lesions were impaired at every spatialnavigation task, whereas rats with posterior parietal lesionshad selective spatial navigation impairments. Rats with prefrontallesions were also impaired at a visual delayed nonmatching-to-sampletask, as they were unable to learn the task, even with no delay.The results are consistent with the idea that the basic planof mammalian cortex includes prefrontal, posterior parietal,and posterior temporal regions, each of which have generallysimilar functions across mammalian taxa. There are, however,species-typical differences that reflect specific ecologicalpressures on the development of the different regions. 相似文献