全文获取类型
收费全文 | 36272篇 |
免费 | 2811篇 |
国内免费 | 372篇 |
专业分类
耳鼻咽喉 | 393篇 |
儿科学 | 993篇 |
妇产科学 | 962篇 |
基础医学 | 4598篇 |
口腔科学 | 608篇 |
临床医学 | 3849篇 |
内科学 | 7747篇 |
皮肤病学 | 832篇 |
神经病学 | 2421篇 |
特种医学 | 1323篇 |
外科学 | 4906篇 |
综合类 | 1196篇 |
一般理论 | 32篇 |
预防医学 | 1987篇 |
眼科学 | 1583篇 |
药学 | 2731篇 |
中国医学 | 307篇 |
肿瘤学 | 2987篇 |
出版年
2023年 | 271篇 |
2022年 | 514篇 |
2021年 | 969篇 |
2020年 | 617篇 |
2019年 | 784篇 |
2018年 | 1002篇 |
2017年 | 768篇 |
2016年 | 877篇 |
2015年 | 1048篇 |
2014年 | 1388篇 |
2013年 | 1661篇 |
2012年 | 2352篇 |
2011年 | 2470篇 |
2010年 | 1424篇 |
2009年 | 1278篇 |
2008年 | 1927篇 |
2007年 | 2004篇 |
2006年 | 2000篇 |
2005年 | 1938篇 |
2004年 | 1703篇 |
2003年 | 1592篇 |
2002年 | 1425篇 |
2001年 | 1131篇 |
2000年 | 1065篇 |
1999年 | 914篇 |
1998年 | 394篇 |
1997年 | 300篇 |
1996年 | 278篇 |
1995年 | 229篇 |
1994年 | 209篇 |
1993年 | 212篇 |
1992年 | 459篇 |
1991年 | 444篇 |
1990年 | 427篇 |
1989年 | 419篇 |
1988年 | 370篇 |
1987年 | 381篇 |
1986年 | 329篇 |
1985年 | 288篇 |
1984年 | 213篇 |
1983年 | 154篇 |
1982年 | 113篇 |
1981年 | 97篇 |
1980年 | 106篇 |
1979年 | 139篇 |
1978年 | 97篇 |
1977年 | 83篇 |
1976年 | 83篇 |
1975年 | 79篇 |
1972年 | 69篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Immunopathologic study of Vogt-Koyanagi-Harada syndrome 总被引:9,自引:0,他引:9
C C Chan A G Palestine T Kuwabara R B Nussenblatt 《American journal of ophthalmology》1988,105(6):607-611
We studied an enucleated eye from a patient with a 30-year history of Vogt-Koyanagi-Harada syndrome using both conventional and immunohistochemical techniques. Clinically, the eye was in the end stage of Vogt-Koyanagi-Harada syndrome, and was characterized by the absence of inflammation, large areas of chorioretinal scarring, and pigmentary changes. Histopathologic examination showed marked retinal gliosis, extensive chorioretinal adhesion and scar formation, migration of pigment into the retina, and severe retinal pigment epithelial changes. However, foci of mild to moderate nongranulomatous inflammation of the uvea were observed. These foci contained infiltrating cells that were mainly T lymphocytes with B lymphocyte aggregates at the center. Scattered macrophages were also noted in the uvea and retina. These findings suggest that both the cell-mediated and humoral immune arms may play roles in the pathogenesis of Vogt-Koyanagi-Harada syndrome. 相似文献
12.
Studies of the ontogeny of IGF-I mRNA during embryonic and larval development of the gilthead sea breamSparus auratashowed its expression during these early developmental stages. The present study appliesin situhybridization to localize IGF-I and IGF receptor mRNAs in 16-day larvae ofS. aurata.Paraffin sections were hybridized with homologous RNA probes labeled by [35S]UTP. IGF-I mRNA expression was found mainly in chondrocytes, in both the gill arches and cranial cartilage, in skeletal muscle, in the brain, in the pancreas, in the retina, and in the epithelial cells surrounding the lens. A strong positive reaction for IGF receptor mRNA was found in skeletal muscle, in the pancreas, and in the lymphoid tissue found in the intertubular tissue of the kidney. Signals were less intense in brain and chondrocytes. It is suggested that in teleosts, as in higher vertebrates, IGF-I may be involved in the regulation of tissue growth and differentiation in an autocrine/paracrine manner. 相似文献
13.
14.
P. P. Fleming A. K. Chan M. G. O’Brien G. C. O’Sullivan M.Ch. FRCSI 《Irish journal of medical science》1997,166(1):13-15
Laparoscopic appendicectomy has been the subject of several encouraging reports, but has not as yet gained widespread acceptance. We present a series of 159 consecutive laparoscopic appendicectomies performed, over a 4 yr period, in both adults and children. We find the procedure as safe as its open counterpart, with patients fit to leave hospital within the same time period. Perforated appendices were amenable to this procedure, and the location of the appendix did not alter the outcome. Children responded as well as adults post-operatively. Obesity may be an indication for this form of treatment. Removal of displaced faecoliths associated with perforated appendicitis is a difficult technical problem in less than 5 per cent of patients. 相似文献
15.
16.
Bibhuti B Das Linda B Pauliks Ole A Knudson Scott Kirby Kak-Chen Chan Lilliam Valdes-Cruz Raul O Cayre 《Journal of the American Society of Echocardiography》2005,18(3):231-236
We identified 18 patients with double-orifice mitral valve (DOMV) and intact atrioventricular (AV) septum out of 40,179 echocardiographic studies performed between 1997 and 2002 at Children's Hospital, Denver, CO. In this study we describe (1) the anatomic characteristics of the DOMV in the absence of AV septal defect, (2) the function of the mitral valve by spectral and color Doppler flow mapping, and (3) associated lesions. The topographic location of the orifices in the leaflets suggests possible embryologic mechanisms of DOMV. In this series, DOMV was most commonly associated with left-sided obstructive lesions (in 39% of patients). Spectral and color Doppler interrogation demonstrated a normal flow profile in most cases; only 2 patients had significant mitral regurgitation or stenosis. Therefore, due to the uncertain natural history of this lesion and the potential need for endocarditis prophylaxis, careful imaging of the mitral valve is recommended, particularly in the presence of left-sided obstructive lesions. 相似文献
17.
This study examines how acute hand injuries affect patients in their roles as spouse, caregiver, and/or worker. Qualitative data from patient interviews were used to analyze how these life roles were affected by the individuals' hand injuries. Data were extracted from interviews of three hand patients who had one or more roles of spouse, caregiver, and/or worker affected by their injury. Data were then examined and categorized for each life role by participant. Participants' views of how hand therapy affected their recovery and resumption of occupational role performance were also examined. Results showed that the participants expressed profound degrees of change in their ability to perform satisfactorily in their various life roles. 相似文献
18.
BACKGROUND: Increased autoantibody prevalence has been described in instances of high-dose exposure to polychlorinated biphenyls (PCBs). In 1996, an equipment malfunction at the Swan Hills Treatment Centre in Alberta, Canada, caused the release of gases containing PCBs into the ambient air. In view of the immune effects of PCBs and their potential as endocrine disruptors, we assessed autoantibody prevalence and looked for correlations with PCB levels. METHODS: Fifty-seven persons living within a 100 km radius of the waste treatment facility were assessed. Autoantibodies were measured by indirect immunofluorescence, double immunodiffusion, and immunoblotting. The levels of 26 congeners of PCBs were measured by gas chromatography and mass spectrometry. Provincial health records for physician visits and hospitalizations were reviewed for diagnoses of autoimmune disease. RESULTS: The prevalence of autoantibodies was 11% in the study participants and 0% in healthy controls. There was no correlation of PCB levels with autoantibody results. There was no associated increase in autoimmune disease noted on physician visits or hospitalizations. PCB levels were comparable to background levels reported for other populations. CONCLUSION: A correlation of titers of autoantibodies in the sera of individuals at risk and the blood levels of PCBs was not found, and the prevalence of autoantibodies in the at-risk group was not statistically different (p > .05) from that of an unexposed control group. The study group had higher titers of autoantibodies and some strong reactivity with intracellular antigens, but the significance of this observation may be understood only after long-term clinical assessments and follow-up. 相似文献
19.
20.
Pneumocystis carinii pneumonia associated with methotrexate therapy in rheumatoid arthritis 总被引:1,自引:0,他引:1
Opportunistic infections occur in patients with rheumatic diseases treated with low dose methotrexate (MTX) with or without other immunosuppressants. Our case report illustrates a fatal case of Pneumocystis carinii pneumonia in a patient with rheumatoid arthritis treated with low dose MTX and glucocorticoid. A review of the literature reveals other opportunistic infections such as Cryptococcus, Nocardia, and herpes zoster presenting in such patients. These occurrences suggest that MTX should be used cautiously in patients with rheumatic disease receiving concomitant medical therapy. 相似文献