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991.
Summary An orientation study on concentration levels of PAH in a closed space was carried out with concern about ventilation and quantity of cigarettes smoked. Emission factors of PAH and their methyl derivatives in the main and side-streams of light and heavy cigarettes were determined.
Innenluftverunreinigung durch polyzyklische aromatische Kohlenwasserstoffe (PAH) im tabakrauch
Zusammenfassung Eine Orientierungsstudie über die PAH-Gehalte in einem geschlossenen Raum wurde in Hinblick auf Ventilation und Anzahl gerauchter Zigaretten durchgeführt. Emissionsfaktoren der PAH und derer Methylhomologen im Haupt- und Nebenrauch wurde bei leichten und starken Zigaretten bestimmt.相似文献
992.
993.
Noncontrast head CT has an important role in the work-up of acute stroke by excluding intracranial hemorrhage and by directly visualizing the parenchymal changes of early infarct. However, noncontrast CT has limited sensitivity and moderate interobserver variability in detecting early infarcts. This article reviews the noncontrast CT appearance and clinical significance of parenchymal changes in early infarct and discusses techniques to optimize their detection. 相似文献
994.
Stacy M. Plum Hong A. Vu Bobby Mercer William E. Fogler Anne H. Fortier 《Immunopharmacology and immunotoxicology》2005,26(1):29-41
Angiogenesis, the process of new capillary formation from pre-existing vessels, has been established as an important mechanism involved in pathologic processes, such as cancer, as well as in normal physiology (Ribatti, D.; Vacca, A.; Roncali, L.; Dammacco, F. Angiogenesis under normal and pathological conditions. Haematologica 1991, 76 (4), 311-320). Basic fibroblast growth factor (FGF-2) is a critical mediator of angiogenesis that is important for normal reproduction and wound healing. FGF-2 mediates its pro-angiogenic effects by binding to heparin sulfate proteoglycan in addition to a tyrosine kinase receptor (Baird, A.; Schubert, D.; Ling, N.; Guillemin, R. Receptor and heparin-binding domain of basic fibroblast growth factor. Proc. Natl. Acad. Sci. U. S. A. 1998, 5 (7), 2324-2328; Richard, C.; Roghani, M.; Moscatelli, D. Fibroblast growth factor (FGF)-2 mediates cell attachment through interactions with two FGF receptor-1 isoforms and extracellular matrix or cell-associated heparin sulfate proteoglycans. Biochem. Biophys. Res. Commun. 2000, 276 (2), 399-405; Casu, B.; Guerrini, M.; Naggi, A.; Perez, M.; Torri, G.; Ribatti, D.; Carminati, P.; Giannini, G.; Penco, S.; Pisano, C.; Belleri, M.; Rusnati, M.; Presta, M. Short heparin sequences spaced by glycol-split urinate residues are antagonists of fibroblast growth factor 2 and angiogenesis inhibitors. Biochemistry 2002, 41 (33), 10519-10528; Murphy, P.V.; Pitt, N.; O'Brien, A.; Enright, P.M.; Dunne, A.; Wilson, S.J.; Duane, R.M.; O'Boyle, K.M. Identification of novel inhibitors of fibroblast growth factor (FGF-2) binding to heparin and endothelial cell survival from a structurally diverse carbohybrid library. Bioorg. Med. Chem. Lett. 2002, 12 (22), 3287-3290). We developed a liposomal-based peptide vaccine, L(HBD) that targets the heparin binding domain of the FGF-2 molecule. This vaccine, when inoculated into mice, inhibits angiogenesis in response to FGF-2 in a hepatic sponge model as well as tumor progression in two models of pulmonary metastatic disease. In the present studies, we further characterize the immunological and physiological responses to this vaccine. Vaccinated animals generated a specific anti-FGF-2 antibody (titer of 1:5000) that was able to inhibit FGF-2 binding to heparin sulfate in a dose dependent fashion. Cell mediated immunity was evidenced by a delayed type hypersensitivity response following challenge with the heparin binding domain peptide. Despite an immune response toward FGF-2, vaccination with L(HBD) did not result in alterations in mean time to wound healing when compared to unvaccinated animals or those treated with a liposome control. In reproductive studies, vaccinated females were not impaired in their ability to: 1) become pregnant, 2) support the growth and development of their embryos, and 3) deliver viable offspring. Furthermore, when assessed histologically, these offspring did not demonstrate any alterations in organogenesis when compared to pups born to untreated or liposome control treated females. Thus, while vaccination against FGF-2 induces a specific FGF-2 antibody response, and inhibits angiogenesis and tumor development in a pathological setting, it does not adversely alter normal physiological events dependent on FGF-2. 相似文献
995.
The β1 integrin very late antigen-4 (VLA-4) plays a key role in lymphocyte rolling and adhesion to endothelium, and in lymphocyte migration through fibronectin. Thus, VLA-4 blockade may modulate allograft rejection. Here, we examined the effect of WAY-279, a small molecule VLA-4 antagonist, combined with sirolimus in a model of vascularized heart allograft (BN → LEW) in the rat. Recipients were treated with low doses of WAY-279 (10-50 mg/kg, bid) and/or sirolimus (0.04 mg/kg) for 14 days, starting on the day of transplantation. The median-effect principle and the combination index (CI) were used to assess the combined effect of WAY-279 and sirolimus (CI < 1: synergism; CI = 1: summation; CI > 1 antagonism). Low doses of WAY-279 or sirolimus alone slightly prolonged allograft survival as compared to control group (MST = 7 days). When recipients were treated with WAY-279 and sirolimus, the cardiac allograft survival was synergistically prolonged for up to 45 days (P < .001; CI = 0.174-0.970). We showed that a concomitant treatment of WAY-279 with sirolimus produced a synergistic effect in prolonging cardiac allograft survival in the rat. 相似文献
996.
Vu M Mai Sean Tutton Pottumarthi V Prasad Qun Chen Wei Li Chi Chen Benjamin Liu Jason Polzin Saban Kurucay Robert R Edelman 《Magnetic resonance in medicine》2003,49(3):591-594
Correlation maps of oxygen-enhanced ventilation were obtained in nine healthy volunteers using complete and selected image series. The complete series included all images acquired with the subjects alternately inhaling room air and 100% oxygen. The selected series were the subsets of the complete series and included only co-registered images that showed matched diaphragmatic position at maximal expiration. Cross-correlation was computed between the time response function of each pixel and the input function representing the alternation between periods of room air and 100% oxygen inhalation. The confidence level for the correlation analysis was set to 0.01. Pulmonary parenchymal anatomy was consistently reproduced throughout the lung, even in anterior slices where published data have reported correlation problems. The overall average correlation coefficient was 0.66 +/- 0.07 for the complete series and 0.75 +/- 0.08 for the selected series. It was concluded that correlation analysis could be used to reconstruct qualitative oxygen-enhanced ventilation maps. 相似文献
997.
Boudreau RJ; Strony JT; duCret RP; Kuni CC; Wang Y; Wilson RF; Schwartz JS; Castaneda-Zuniga WR 《Radiology》1990,175(1):103-105
Eighty patients with type I diabetes and end stage renal disease were prospectively evaluated for coronary artery disease with dipyridamole-thallium-201 scintigraphy and quantitative coronary angiography. Forty patients received dipyridamole orally, and 40 received it intravenously. The prevalence of coronary artery disease was 53%. There were no significant differences in the accuracy of the two dipyridamole tests (sensitivity = 85%, specificity = 85%, accuracy = 85% for the oral group; sensitivity = 86%, specificity = 72%, accuracy = 79% for the intravenous group). Combining the 80 patients into a single group gave a sensitivity of 86%, a specificity of 79%, and an accuracy of 83% for the detection of coronary disease. Although the accuracy of this test in this patient population was similar to that previously reported for other groups, the prevalence of disease was high and resulted in a low predictive value of a negative test (83%). 相似文献
998.
The prevalence of diet-induced migraine 总被引:2,自引:1,他引:1
RC Peatfield V Glover JT Littlewood M Sandler F Clifford Rose 《Cephalalgia : an international journal of headache》1984,4(3):179-183
Nineteen percent of about 490 patients with classical or common migraine reported that headaches can be precipitated by chocolate, 18% by cheese and 11% by citrus fruit, and a highly significant majority of these patients were sensitive to all three foods. Twenty-nine percent of the patients reported sensitivity to alcohol; again this was significantly associated with sensitivity to the three food stuffs, though a substantial number of patients were sensitive to alcohol but not foods. Thirty-one percent of 331 female patients believed that oral contraceptives precipitated headaches, but this could not be related to any dietary response. Patients with affected relatives were significantly more likely to report sensitivity to alcohol and chocolate; sensitivity to cheese and citrus fruit was less strongly related, and there was no relationship at all for oral contraceptives. These correlations suggest that food induced headaches are mediated by chemical constituents common to these foods. 相似文献
999.
Basilar pneumothorax in the supine adult 总被引:2,自引:0,他引:2
1000.
Computed tomography in cerebellar atrophic processes 总被引:4,自引:0,他引:4