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101.
JW Mosley ; W Huang ; DO Stram ; MJ Nowicki ; FB Hollinger ; RD Aach ; CE Stevens ; LH Barbosa ; GJ Nemo 《Transfusion》1996,36(9):776-781
BACKGROUND: Hepatitis virus(es) that are neither hepatitis B (HBV) nor hepatitis C (HCV) (non-B, non-C [NBNC]) may be transmitted by transfusion. The present study assessed donor values for alanine aminotransferase (ALT) and antibody to hepatitis B core antigen (anti- HBc) for their association with HCV and NBNC hepatitis outcomes among allogeneic blood recipients. STUDY DESIGN AND METHODS: Data on blood donors and recipients enrolled in the Transfusion- Transmitted Viruses Study in four United States cities from 1974 through 1980 were supplemented by anti-HBc testing of donors and anti-HCV evaluation of recipients. Two statistical approaches estimated the value of these indirect tests in detecting donors associated with HCV seroconversion and NBNC hepatitis in recipients. RESULTS: For HCV cases, donor ALT alone (at > or = 60 IU/L) had a sensitivity and a specificity of 30 and 96 percent, respectively, and anti-HBc alone (at > or = 60% inhibition) had a sensitivity and specificity of 53 and 86 percent, respectively. The two markers combined had a sensitivity and a specificity of 69 and 83 percent. For NBNC hepatitis cases, each measure had low sensitivity (20%) that was not improved by using both (28%) [corrected]. CONCLUSION: The indirect tests proved to be equal in sensitivity to the first-generation anti-HCV tests. The positive predictive power of these indirect tests in the 1980s was sufficient to affect HCV incidence in studies during that period. Improved anti-HCV assays, however, replaced the need for indirect tests. The sensitivity of indirect tests for NBNC hepatitis contributed little. 相似文献
102.
The present criteria for confirmation of human T-lymphotrophic virus types I and II (HTLV-I/II) infection in blood donors are based on seroreactivity to p24 (gag) and gp46 and/or gp61 (env) on Western blot (WB) and radioimmunoprecipitation assays (WB/RIPA). Any single band and other combinations are classified as indeterminate. This case report documents infection in a donor with a repeatedly indeterminate pattern. The blood donor was anti-HTLV-I/II positive on enzyme-linked immunoassay, and two sera taken 5 years apart were WB/RIPA-indeterminate (p19 and gp68 only). His donations in the interval were associated with transmission of HTLV-I to four of the six recipients available for study. Other recipients of blood from donors whose WB/RIPA results were indeterminate by present criteria should be examined to determine if additional patterns are at least occasionally associated with transmission. The likelihood that such donors are infected is important to those who are counseling them and making decisions concerning recipients of their bloody. 相似文献
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The purpose of this article is to explicate research funding and training opportunities available through the Department of Veterans Affairs to nurses seeking advanced preparation at the pre- and post-doctoral levels. A brief discussion of the available resources including student stipend and health insurance, workspace, and research support is presented. Additionally, articulation of the benefits and challenges associated with these types of fellowships is delineated from the perspective of a fellow, Department of Veterans Affairs (VA) site preceptor, and dissertation faculty. Discussion of the post-doctoral fellowship and the extensive resources of the VA related to overall research career development are also addressed. 相似文献
108.
Previous studies have demonstrated that systemically administered immunotherapy can protect mice from systemic challenge with the bacterial pathogen Francisella tularensis. However, for protection from inhalational challenge with this bacterium, we wondered if mucosally administered immunotherapy might be more effective. Therefore, we administered cationic liposome–DNA complexes (CLDC), which are potent activators of innate immunity, intranasally (i.n.) and assessed the effectiveness of protection from lethal inhalational challenge with F. tularensis. We found that pretreatment by i.n. administration of CLDC 24 h prior to bacterial challenge elicited nearly complete protection of BALB/c mice from lethal challenge with F. tularensis LVS strain. We also observed that mucosal CLDC immunotherapy provided a statistically significant increase in survival time in mice challenged with the highly virulent F. tularensis Schu4 strain. Protection was associated with a significant reduction in bacterial burden in the lungs, liver, and spleen. Mucosal administration of CLDC elicited significantly increased expression of IL-12, IFN-γ, TNF-α, IFN-β and IFN-α genes in the lung as detected by real-time quantitative PCR. In vitro treatment of F. tularensis infected macrophages with CLDC-elicited cytokines also significantly suppressed intracellular replication of F. tularensis in infected macrophages. In vivo, depletion of NK cells prior to administration of CLDC completely abolished the protective effects of CLDC immunotherapy. CLDC-elicited protection was also dependent on induction of IFN-γ production in vivo. We conclude therefore that activation of local pulmonary innate immune responses is capable of eliciting significant protection from inhalational exposure to a virulent bacterial pathogen. 相似文献
109.
Jackson BM Carpenter JP Fairman RM Moser GW Pochettino A Woo EY Bavaria JE 《Journal of vascular surgery》2007,45(4):662-666
OBJECTIVES: We sought to define the current anatomic barriers to thoracic aortic aneurysm (TAA) stent grafting to guide future device development. METHODS: All patients presenting with TAA requiring repair were evaluated for endovascular repair during a 4-year period (2000 to 2004). The TAAs evaluated were those beginning distal to the left common carotid artery (LCCA) and ending proximal to the celiac artery. All patients in whom endovascular repair was indicated underwent cross-sectional imaging by computed tomography angiography and three-dimensional modeling of their thoracic and abdominal arterial anatomy. Patients were evaluated for endovascular TAA repair in the context of the inclusion/exclusion criteria of pivotal United States Food and Drug Administration trials of the Gore TAG and Medtronic Talent devices. Anatomic requirements included >or=20 mm of suitable proximal and distal neck length, and proximal and distal neck diameters of 20 to 42 mm. These trials allowed the use of femoral or iliac access, including the use of conduits, and permitted stent graft coverage of the left subclavian artery (LSA) after preliminary carotid-subclavian bypass. Patients rejected for medical reasons or who died during evaluation were not included in the review. RESULTS: A total of 126 patients (73 men, 53 women) with TAA located between the LCCA and celiac artery were screened for endovascular repair, and 33 (26%) were rejected for anatomic reasons. The remaining 93 patients underwent endografting (59 Talent, 34 TAG). Rejection was not significantly different by gender (16/73 men, 17/53 women, P = .22, NS). Most patients (28/33) were rejected for more than one criterion. Hostile proximal neck characteristics were the most prevalent reason for disqualification, despite the ability to cover the LSA to extend the proximal seal zone. Many of these patients (16/28) also had distal neck anatomy unsuitable for grafting. Overall, 19 patients had hostile distal necks. Difficulties with vascular access (diseased or tortuous iliac arteries, or a small caliber aorta) that could not be overcome even by use of conduits occurred in a significant fraction of patients (10/33). CONCLUSIONS: Most patients with a TAA located between the LCCA and the celiac artery can be treated by endovascular repair. Patients excluded from TAA stent graft protocols for anatomic reasons most commonly have hostile proximal neck features that preclude endovascular repair with currently available devices. Transposition of arch vessels to facilitate greater use of existing stent grafts or development of new stent graft designs are needed to expand the applicability of TAA endovascular repair. 相似文献
110.
Martin Fairman 《British medical journal》2000,320(7243):1204