全文获取类型
收费全文 | 404篇 |
免费 | 50篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 14篇 |
妇产科学 | 2篇 |
基础医学 | 68篇 |
口腔科学 | 8篇 |
临床医学 | 53篇 |
内科学 | 153篇 |
皮肤病学 | 2篇 |
神经病学 | 9篇 |
特种医学 | 49篇 |
外科学 | 18篇 |
综合类 | 3篇 |
预防医学 | 44篇 |
眼科学 | 1篇 |
药学 | 13篇 |
中国医学 | 1篇 |
肿瘤学 | 13篇 |
出版年
2024年 | 2篇 |
2022年 | 1篇 |
2021年 | 4篇 |
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 5篇 |
2016年 | 9篇 |
2015年 | 1篇 |
2014年 | 8篇 |
2013年 | 8篇 |
2012年 | 11篇 |
2011年 | 17篇 |
2010年 | 15篇 |
2009年 | 15篇 |
2008年 | 14篇 |
2007年 | 27篇 |
2006年 | 22篇 |
2005年 | 23篇 |
2004年 | 12篇 |
2003年 | 9篇 |
2002年 | 11篇 |
2001年 | 12篇 |
2000年 | 16篇 |
1999年 | 9篇 |
1998年 | 14篇 |
1997年 | 16篇 |
1996年 | 10篇 |
1995年 | 6篇 |
1994年 | 10篇 |
1993年 | 7篇 |
1992年 | 9篇 |
1991年 | 10篇 |
1990年 | 5篇 |
1989年 | 17篇 |
1988年 | 17篇 |
1987年 | 17篇 |
1986年 | 10篇 |
1985年 | 15篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 2篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1976年 | 4篇 |
1975年 | 7篇 |
1973年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有454条查询结果,搜索用时 15 毫秒
71.
Evidence of endothelial dysfunction in angiographically normal coronary arteries of patients with coronary artery disease 总被引:12,自引:0,他引:12
Acetylcholine causes endothelium-dependent dilation of normal arteries in most animal species. The effect of acetylcholine on normal human coronary arteries is controversial. Pathologic studies and epicardial echocardiography have shown that diffuse atherosclerosis is often present despite angiographic evidence of discrete coronary artery disease (CAD). Therefore, we postulated that acetylcholine would cause vasoconstriction of coronary arteries that are angiographically normal in patients with CAD. Coronary artery diameter, measured by automated quantification of digitized cineangiograms, was determined before and after the intracoronary infusion of 0.2 mM acetylcholine at 0.8-1.6 ml/min. The diameter of stenotic or irregular segments of six atherosclerotic coronary arteries decreased from 1.80 +/- 0.42 mm before acetylcholine to 1.26 +/- 0.46 mm after acetylcholine (p = 0.0025). Acetylcholine had a significantly different effect on the diameter of two groups of coronary arteries that are angiographically normal. Acetylcholine caused a 0.16 +/- 0.09-mm increase in the diameter of 14 normal coronary arteries in patients without CAD, whereas it caused a 0.26 +/- 0.12-mm decrease in the diameter of 14 normal coronary arteries in patients with CAD (p less than 0.01). Thus, the normal response to intracoronary acetylcholine is vasodilation, suggesting that endothelium-derived relaxing factor is released from normal human coronary endothelium. The vasoconstrictive effect of acetylcholine in the angiographically normal coronary arteries of patients with CAD suggests the presence of a diffuse abnormality of endothelial function. 相似文献
72.
Deisseroth AB; Zu Z; Claxton D; Hanania EG; Fu S; Ellerson D; Goldberg L; Thomas M; Janicek K; Anderson WF 《Blood》1994,83(10):3068-3076
Relapse after autologous bone marrow transplantation for chronic myelogenous leukemia (CML) can be due either to the persistence of leukemia cells in systemic tissues following preparative therapy, or due to the persistence of leukemia cells in the autologous marrow used to restore marrow function after intensive therapy. To help distinguish between these two possible causes of relapse, we used safety-modified retroviruses, which contain the bacterial resistance gene NEO, to mark autologous marrow cells that had been collected from patients early in the phase of hematopoietic recovery after in vivo chemotherapy. The cells were then subjected to ex vivo CD34 selection following collection and 30% of the bone marrow were exposed to a safety-modified virus. This marrow was infused after delivery of systemic therapy, which consisted of total body irradiation (1,020 cGy), cyclophosphamide (120 mg/kg), and VP-16 (750 mg/m2). RT PCR assays specific for the bacterial NEO mRNA, which was coded for by the virus, and the bcr-abl mRNA showed that in two evaluable CML patients transplanted with marked cells, sufficient numbers of leukemia cells remained in the infused marrow to contribute to systemic relapse. In addition, both normal and leukemic cells positive for the retroviral transgenome persisted in the systemic circulation of the patients for at least 280 days posttransplant showing that the infused marrow was responsible for the return of hematopoiesis following the preparative therapy. This observation shows that it is possible to use a replication-incompetent safety-modified retrovirus in order to introduce DNA sequences into the hematopoietic cells of patients undergoing autologous bone marrow transplantation. Moreover, this data suggested that additional fractionation procedures will be necessary to reduce the probability of relapse after bone marrow transplantation in at least the advanced stages of the disease in CML patients undergoing autologous bone marrow transplantation procedures. 相似文献
73.
74.
75.
Martin JE Louder MK Holman LA Gordon IJ Enama ME Larkin BD Andrews CA Vogel L Koup RA Roederer M Bailer RT Gomez PL Nason M Mascola JR Nabel GJ Graham BS;VRC Study Team 《Vaccine》2008,26(50):6338-6343
BACKGROUND: The severe acute respiratory syndrome (SARS) virus is a member of the Coronaviridae (CoV) family that first appeared in the Guangdong Province of China in 2002 and was recognized as an emerging infectious disease in March 2003. Over 8000 cases and 900 deaths occurred during the epidemic. We report the safety and immunogenicity of a SARS DNA vaccine in a Phase I human study. METHODS: A single-plasmid DNA vaccine encoding the Spike (S) glycoprotein was evaluated in 10 healthy adults. Nine subjects completed the 3 dose vaccination schedule and were evaluated for vaccine safety and immune responses. Immune response was assessed by intracellular cytokine staining (ICS), ELISpot, ELISA, and neutralization assays. RESULTS: The vaccine was well tolerated. SARS-CoV-specific antibody was detected by ELISA in 8 of 10 subjects and neutralizing antibody was detected in all subjects who received 3 doses of vaccine. SARS-CoV-specific CD4+ T-cell responses were detected in all vaccinees, and CD8+ T-cell responses in approximately 20% of individuals. CONCLUSIONS: The VRC SARS DNA vaccine was well tolerated and produced cellular immune responses and neutralizing antibody in healthy adults. 相似文献
76.
Transabdominal and endovaginal pelvic sonograms were obtained in 108 nonpregnant patients referred for pelvic sonography. The studies were independently obtained by two radiologists and interpreted on the basis of identical clinical information. The sonograms were then compared for anatomic detail and abnormalities. A determination was made about which examination, if either, was superior. Follow-up was performed through a review of the medical records and follow-up studies. Overall, the endovaginal study was judged superior in 65 cases (60.2%), equal in 39 (36.1%), and inferior in four (3.7%). The authors conclude that the endovaginal examination can effectively replace the transabdominal examination as the initial approach for routine pelvic sonography. 相似文献
77.
78.
79.
Paulsson AK McMullen KP Peiffer AM Hinson WH Kearns WT Johnson AJ Lesser GJ Ellis TL Tatter SB Debinski W Shaw EG Chan MD 《中国神经肿瘤杂志》2013,(1):52-52
PURPOSE: We investigate the patterns of failure in the treatment of glioblastoma(GBM) based on clinical target volume(CTV) margin size,dose delivered to the site of initial failure,and the use of temozolomide and intensity-modulated radiotherapy(IMRT).METHODS: Between August 2000 and May 2010,161 patients with GBM were treated with radiotherapy with or without concurrent temozolomide.Patients were treated with CTV expansions that ranged from 5 to 20 mm using a shrinking field technique.Patterns of failure and time to progression and overall survival were compared based on CTV margin,use of temozolomide,and use of IMRT.Kaplan Meier analysis was used to estimate survival times,and χ test was used for comparison of cohorts.RESULTS: For patients treated with 5-,10-,and 15-to 20-mm CTV,79%,77%,and 86% experienced failures in the 60 Gy volume,respectively.Forty-eight percent,55%,and 66% of patients with 5-,10-,and 15-to 20-mm CTV experienced failures in the 46 Gy volume,respectively.There was no statistical difference between patients treated with 5-,10-,15-to 20-mm margins with regard to 60 Gy failure(P=0.76),46 Gy failure(P=0.51),or marginal failure(P=0.73).Eighty percent of patients receiving temozolomide experienced failures in the 60 Gy volume.There was no increased likelihood of marginal failures in patients receiving IMRT(P =0.97).CONCLUSIONS: Modern treatment techniques including use of concurrent temozolmide,limited CTV margin size,and IMRT have not greatly changed the patterns of failure of GBM. 相似文献
80.
Hemorrhagic fever viruses as biological weapons: medical and public health management 总被引:16,自引:1,他引:16
Borio L Inglesby T Peters CJ Schmaljohn AL Hughes JM Jahrling PB Ksiazek T Johnson KM Meyerhoff A O'Toole T Ascher MS Bartlett J Breman JG Eitzen EM Hamburg M Hauer J Henderson DA Johnson RT Kwik G Layton M Lillibridge S Nabel GJ Osterholm MT Perl TM Russell P Tonat K;Working Group on Civilian Biodefense 《JAMA》2002,287(18):2391-2405
OBJECTIVE: To develop consensus-based recommendations for measures to be taken by medical and public health professionals if hemorrhagic fever viruses (HFVs) are used as biological weapons against a civilian population. PARTICIPANTS: The Working Group on Civilian Biodefense included 26 representatives from academic medical centers, public health, military services, governmental agencies, and other emergency management institutions. EVIDENCE: MEDLINE was searched from January 1966 to January 2002. Retrieved references, relevant material published prior to 1966, and additional sources identified by participants were reviewed. CONSENSUS PROCESS: Three formal drafts of the statement that synthesized information obtained in the evidence-gathering process were reviewed by the working group. Each draft incorporated comments and judgments of the members. All members approved the final draft. CONCLUSIONS: Weapons disseminating a number of HFVs could cause an outbreak of an undifferentiated febrile illness 2 to 21 days later, associated with clinical manifestations that could include rash, hemorrhagic diathesis, and shock. The mode of transmission and clinical course would vary depending on the specific pathogen. Diagnosis may be delayed given clinicians' unfamiliarity with these diseases, heterogeneous clinical presentation within an infected cohort, and lack of widely available diagnostic tests. Initiation of ribavirin therapy in the early phases of illness may be useful in treatment of some of these viruses, although extensive experience is lacking. There are no licensed vaccines to treat the diseases caused by HFVs. 相似文献