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M Ferrari M Armani P Melacini C Egloff G Scattolin G Fasoli G Cardin G Miraglia C Angelini S Dalla Volta 《Giornale italiano di cardiologia》1980,10(10):1288-1298
17 patients with myotonic dystrophy have been studied. The skeletal muscle disease has been assessed by history, physical examination, electro-myography and muscle biopsy. Cardiac evaluation has been obtained by history, physical examination, chest X-ray, ecg at rest and after exercise, vectorcardiography and echocardiography. Only two patients presented symptoms and clinical findings of cardiac disease, otherwise conduction disturbances have been founded in 15 cases, pseudoinfarct pattern in 5 cases and loss of anterior vectors in 2 cases. Has to be remembered that in myotonic dystrophy sudden death has a very high incidence, which could be explained by the development of complete a-v block, because of the impairment of the conduction system. Therefore, in those patients with bifascicular blocks (3 cases), the electrophysiological study may be useful in order to evaluate the opportunity to put on a permanent pace-maker, to prevent sudden death. 相似文献
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Vito A. Angelillo 《Postgraduate medicine》2013,125(2):336-345
Breathlessness is a common complaint. Often the cause is readily apparent, but in some circumstances it may be quite obscure. Sometimes it is not even clear whether dyspnea is really present. Dr Angelillo's article discusses the pathophysiology of dyspnea, provides information about its clinical evaluation, and gives pointers for determining its specific cause in the individual patient. 相似文献
25.
Fabiana Miraglia Minekazo Matsuo Zenaide Maria Morais Odir Antonio Dellagostin Fabiana Kömmling Seixas Julio César Freitas Rudy Hartskeerl Luisa Zanolli Moreno Bárbara Letícia Costa Gisele Oliveira Souza Silvio Arruda Vasconcellos Andrea Micke Moreno 《Diagnostic microbiology and infectious disease》2013
Leptospira interrogans serogroup Icterohaemorrhagiae is the major serogroup infecting humans worldwide, and rodents and dogs are the most significant transmission sources in urban environments. Knowledge of the prevalent serovars and their maintenance hosts is essential to understand the epidemiology of leptospirosis. In this study, 20 Leptospira isolates were evaluated by pulsed-field gel electrophoresis (PFGE), variable number tandem-repeat analysis (VNTR), serotyping, and determination of antimicrobial resistance profile. Isolates, originated from bovine, canine, human, and rodent sources, were characterized by microscopic agglutination test with polyclonal and monoclonal antibodies and were identified as L. interrogans serogroup Icterohaemorrhagiae serovar Copenhageni. MICs of antimicrobials often used in veterinary medicine were determined by broth microdilution test. Most of tested antibiotics were effective against isolates, including penicillin, ampicillin, and ceftiofur. Higher MIC variability was observed for fluoroquinolones and neomycin; all isolates were resistant to trimethoprim/sulfamethoxazole and sulphadimethoxine. Isolates were genotyped by PFGE and VNTR; both techniques were unable to discriminate between serovars Copenhageni and Icterohaemorrhagiae, as expected. PFGE clustered all isolates in 1 pulsotype, indicating that these serovars can be transmitted between species and that bovine, rodent, and dogs can maintain them in the environment endangering the human population. 相似文献
26.
Impaired in vitro growth of PHA induced T lymphocyte colonies in hemodialyzed renal failure patients
Riccardo Ghio Enrico Haupt Vito Pistoia Angela Perata Paola Minale Massimo Ratti Piero Boccaccio 《Annals of hematology》1985,50(3):135-140
Summary Using an in vitro method that allows the study of the colony forming capacity of phytohemagglutinin stimulated peripheral blood T lymphocytes, we have detected an impaired T cell colony formation in hemodialyzed renal failure patients. By contrast a near normal pattern of responses was observed in patients treated with a conservative therapy. The poor in vitro T cell responsiveness of hemodialyzed patients was not corrected by supplementing the cultures with an adherent cell contitioned medium prepared from normal donors. We conclude that an intrinsic defect of the T cell colony forming capacity exists in hemodialyzed patients. 相似文献
27.
The effect of fibrin polymers on thrombin-catalyzed factor XIIIa formation was studied in afibrinogenemic plasma. Fibrin polymers derived from des A fibrinogen and des A,B fibrinogen increased sixfold the rate of thrombin-catalyzed factor XIIIa formation in the presence of EDTA. Calcium chloride accelerated factor XIIIa formation 14-fold in the presence of des A,B fibrinogen without increasing the rate of thrombin formation. Fibrinopeptides A and B had no effect on factor XIIIa formation in afibrinogenemic plasma. Des A,B fibrinogen reduced by 20- to 40-fold the thrombin concentration required to activate factor XIII. Glycyl-L-prolyl-L-arginyl-L-proline (gly-pro-arg-pro), a fibrin polymerization inhibitor, inhibited des A and des A,B fibrinogen from enhancing thrombin-catalyzed factor XIIIa formation. Gly-pro-arg- pro did not modify factor XIIIa formation in afibrinogenemic plasma and did not inhibit thrombin cleavage of the chromogenic substrate S-2238. These results demonstrate that fibrin polymers accelerate thrombin- catalyzed plasma factor XIIIa formation. 相似文献
28.
Regulation of plasma factor XIII binding to fibrin in vitro 总被引:2,自引:2,他引:2
The binding of plasma factor XIII to fibrinogen or fibrin that has been chemically or enzymatically induced to polymerize was studied. Factor XIII binding was assayed using a 3H-putrescine incorporation assay and an 125I-plasma factor XIII binding assay. More than 80% of the native and radiolabeled plasma factor XIII was bound to fibrin I formed by reptilase in EDTA, citrate, or heparin anticoagulated plasma. Plasma factor XIII and 125I-factor XIII was bound (89.6% to 92.5%) to fibrin II formed by thrombin in either citrate or EDTA anticoagulated plasma. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of 125I-plasma factor XIII bound to fibrin I or fibrin II formed by reptilase or thrombin in the presence of EDTA demonstrated the b2-subunit remained bound to the a-chains or thrombin-cleaved a-chains. In the presence of calcium chloride and thrombin, the b2-subunit dissociated and factor XIIIa was bound. Protamine sulfate caused fibrinogen polymerization in the absence of divalent cations and reduced both plasma factor XIII and immunologic fibrinogen levels. Fibrinogen polymerized by protamine sulfate bound plasma factor XIII and the a2-subunit of 125I-platelet factor XIII. Plasma factor XIII was also bound to sonicated non-cross-linked fibrin II in either normal plasma or afibrinogenemic plasma. Plasma levels of several coagulation proteins were unchanged after the addition of reptilase, protamine sulfate, or sonicated fibrin to plasma. These results demonstrate that a specific binding site for the a2-subunit of plasma factor XIII is present on polymerized fibrinogen, fibrin I, and fibrin II. Furthermore, the presence of divalent cations, thrombin-cleavage of plasma factor XIII, and release of fibrinopeptides A or B are not required for plasma factor XIII binding to polymerized fibrinogen and fibrin. 相似文献
29.
Immunoreactive thyroid-stimulating hormone (IR-TSH) has been detected in the hypothalamus and is released in vitro by a calcium-dependent mechanism when the tissue is depolarized. Recently, immunocytochemical studies have revealed that IR-TSH is present in thyrotropes in the pars tuberalis. Therefore, because these thyrotropes are associated with the median eminence, the area with the highest concentration of IR-TSH, it is of interest to determine if 'hypothalamic' IR-TSH is from neural or pituitary cells. We addressed this issue by studying the effects of hypophysectomy, thyroidectomy, or chronic administration of triiodothyronine (T3) or thyroxine (T4) on the distribution and in vitro release of IR-TSH in the hypothalamus. We reasoned that, if hypothalamic IR-TSH is dependent on the thyrotropes of the pars tuberalis, then changes in hypothalamic IR-TSH concentration and release should be parallel to those measured in pituitary extracts. IR-TSH was measured in tissue extracted in ice-cold 2% NaCl, with a final pH of 4.5. For the in vitro studies, tissues were incubated for 20-min periods in Krebs-Ringer bicarbonate buffer at 37 degrees C. In untreated rats, the concentration of IR-TSH is greater in the ventral than the dorsal portion of the hypothalamus (39.3 +/- 8.2 vs. 4.0 +/- 1.5 ng/mg wet wt.). Upon finer dissection of the hypothalamus into median eminence and anterior, middle, and posterior portions of the remainder, IR-TSH was only detectable in the middle hypothalamus (5.3 +/- 1.5 ng/mg), and the median eminence (149 +/- 41 ng/mg).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
30.
Olivier Facy Vito De Blasi Martine Goergen Luca Arru Luigi De Magistris Juan-Santiago Azagra 《Surgical endoscopy》2013,27(10):3841-3845