全文获取类型
收费全文 | 296155篇 |
免费 | 17586篇 |
国内免费 | 416篇 |
专业分类
耳鼻咽喉 | 4205篇 |
儿科学 | 10291篇 |
妇产科学 | 10253篇 |
基础医学 | 45006篇 |
口腔科学 | 7500篇 |
临床医学 | 24195篇 |
内科学 | 55827篇 |
皮肤病学 | 6313篇 |
神经病学 | 21103篇 |
特种医学 | 11641篇 |
外国民族医学 | 43篇 |
外科学 | 46694篇 |
综合类 | 7765篇 |
现状与发展 | 1篇 |
一般理论 | 160篇 |
预防医学 | 19914篇 |
眼科学 | 6943篇 |
药学 | 20886篇 |
中国医学 | 786篇 |
肿瘤学 | 14631篇 |
出版年
2018年 | 3616篇 |
2017年 | 2658篇 |
2016年 | 3075篇 |
2015年 | 3501篇 |
2014年 | 4583篇 |
2013年 | 7211篇 |
2012年 | 9082篇 |
2011年 | 9461篇 |
2010年 | 6133篇 |
2009年 | 5558篇 |
2008年 | 8678篇 |
2007年 | 9531篇 |
2006年 | 9370篇 |
2005年 | 8969篇 |
2004年 | 8669篇 |
2003年 | 8170篇 |
2002年 | 7759篇 |
2001年 | 13332篇 |
2000年 | 13656篇 |
1999年 | 11422篇 |
1998年 | 3025篇 |
1997年 | 2790篇 |
1996年 | 2636篇 |
1995年 | 2552篇 |
1994年 | 2348篇 |
1992年 | 8319篇 |
1991年 | 8458篇 |
1990年 | 8262篇 |
1989年 | 8088篇 |
1988年 | 7324篇 |
1987年 | 7078篇 |
1986年 | 6731篇 |
1985年 | 6523篇 |
1984年 | 4768篇 |
1983年 | 4121篇 |
1982年 | 2469篇 |
1979年 | 4434篇 |
1978年 | 3229篇 |
1977年 | 2732篇 |
1976年 | 2504篇 |
1975年 | 2836篇 |
1974年 | 3356篇 |
1973年 | 3363篇 |
1972年 | 3122篇 |
1971年 | 2949篇 |
1970年 | 2838篇 |
1969年 | 2583篇 |
1968年 | 2538篇 |
1967年 | 2373篇 |
1966年 | 2265篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
121.
Recurrent erosion 总被引:1,自引:0,他引:1
122.
Electrocardiographic symptoms were evaluated in 53 patients with an additional left-ventricular chorda (ALVC), detected by two-dimensional echocardiography. Signs of early ventricular repolarization (EVR) were identified in 45 (84.9%) patients. A transverse ALVC was more common in EVR-free patients (87.5%), as compared to patients with ALVC + EVR combinations (51.1%; p less than 0.05). 相似文献
123.
Sarah A. Taylor Jacqueline Benedetti David Schuller Stephen P. Richman Goronwy O. Broun Alexander Hantel 《Investigational new drugs》1993,11(2-3):227-229
Summary Twenty-two patients with recurrent or metastatic squamous cell carcinoma of the head and neck were treated with piroxantrone 150 mg/m2 intravenously every 21 days. There were no objective responses. The 95% upper confidence bound for response is 15%. Primary toxicity was hematologic. 相似文献
124.
Oil-emulsified (OE) and aqueous (Aq) vaccines were prepared with the same batch of inactivated A24 8345 foot and mouth disease virus (FMDV). Calves born to vaccinated dams did not respond to the Aq vaccine 30 or 90 days post partum. When the OE vaccine was used on a similar group of calves, no responses were elicited up to 21 days post partum. However, calves 30 or more days old responded like adult cattle to the OE vaccine. When the OE vaccine was used in colostral antibody-free calves 3-30 days old, all animals showed good antibody responses but, in calves vaccinated 3 or 7 days post partum, antibodies were detectable only after a considerable period of time. Our results show that both passively acquired colostral antibodies and age are important in the response of very young calves to FMDV oil vaccines. From a practical point of view, in endemic areas where adult cattle are periodically vaccinated, vaccination of calves between 30 and 60 days post partum with OE vaccines would lead to high levels of herd protection. 相似文献
125.
Relation between energy expenditure and body composition in man: specific energy expenditure in vivo of fat and fat-free tissue 总被引:2,自引:0,他引:2
L Garby J S Garrow B J?rgensen O Lammert K Madsen P S?rensen J Webster 《European journal of clinical nutrition》1988,42(4):301-305
The relationship between energy expenditure and body composition, in terms of fat and fat-free masses, has previously been described by a variety of predictive regression equations with parameters devoid of physiological content. We present here results obtained by calculating the specific energy expenditure, ie, the energy expenditure per unit of mass, of fat and fat-free tissue on the basis of measurements of the total energy expenditure (EE), the masses of fat (FM), and fat-free (FFM) tissue using the following simple model: EE = k1.FM + k2.FFM where k1 and k2 are the specific energy expenditures of fat and fat-free tissue, respectively. The results of observations on 104 women at rest yielded values for k1 and k2 of 0.31 and 1.35 watts/kg of fat and fat-free mass, respectively, with standard errors of estimate of 0.074 and 0.052 watts/kg, respectively. Analysis of several series of measurements, from other sources and on smaller samples of subjects, yielded similar values at rest but with larger standard errors of estimate. Data from subjects performing varying amounts of work in 24-h measurements showed, as expected, larger values for both tissues. The results explain to a very large extent the well-established relation between resting metabolic rate and body weight, ie, a linear relation with a non-zero intercept. The results also offer a clear-cut explanation for the well known difference in energy expenditure between men and women with the same body weight. 相似文献
126.
N A Athanasou C A Wells J Quinn D P Ferguson A Heryet J O McGee 《British journal of cancer》1989,59(4):491-498
The origin and nature of osteoclast-like multinucleated giant cells (OMGCs), in extraskeletal neoplasms, is uncertain. The ultrastructure, antigenic phenotype and function of OMGCsm in a breast carcinoma were studied in order to clarify the relationship between OMGCs, osteoclasts and other cells of the mononuclear phagocyte system (MPS). OMGCs resorbed cortical bone in a manner similar to osteoclasts. However, unlike osteoclasts, OMGCs did not possess a ruffled border or clear zone, and expressed HLA-DR and Fc receptors and CD14, CD16, CD18 and CD11 (p150,95) antigens. In addition, OMGCs failed to respond morphologically to calcitonin and were directly stimulated by parathyroid hormone (PTH) to increase bone resorption. These findings suggest that OMGCs are a specific type of macrophage polykaryon distinct from both osteoclasts and other types of inflammatory polykaryon. Occasional smaller (20-25 microns) macrophage-like cells were also associated with resorption pits. Bone resorption by OMGCs isolated from the breast indicates that a cell of the MPS can be transplanted to a new tissue location and perform a highly specialised function appropriate to an MPS cell of that tissue (i.e. the osteoclast). PTH stimulation of bone resorption by OMGCs suggests that PTH or a PTH-like protein, may be involved in the bone resorption and consequent hypercalcaemia associated with metastatic breast cancer. 相似文献
127.
128.
B. J. d'Othe S. Haulon C. Mounier-Vehier J. P. Beregi O. Jabourek S. Willoteaux 《European journal of vascular and endovascular surgery》2002,24(6):516-523
OBJECTIVE: evaluation and comparison of the endovascular treatment of isolated aortic and aortoiliac atherosclerotic lesions (stenoses and occlusions). METHODS: a percutaneous endovascular procedure was performed in 52 patients (38 men and 14 women) with a mean age of 52 years (range, 25-85 years). The baseline angiogram showed 35 aortic lesions (31 stenoses, 4 occlusions) and 17 aortoiliac lesions (14 stenoses, 3 occlusions). Percutaneous techniques used in this series included variable combinations of transluminal angioplasty and stenting. All stents placements were performed over-the-wire using the transfemoral route (most often bilateral approach). Clinical examination and Duplex-scan were performed at discharge, 1 month, 6 months, 12 months, and then yearly. RESULTS: technical success was 100% for aortic and aortoiliac lesions. Angiographic success rates were comparable for aortic (91%) and aortoiliac (94%) lesions. No death occurred during or early after the endovascular intervention. Duplex-scan confirmed 100% patency rate at discharge. There was no significant difference between the aortic (94%) and aortoiliac (96%) groups regarding immediate clinical improvement. Mean follow-up was 34+/-31 months (range, 0-130 months). The cumulative primary patency rate at 36 months was 85% in the aortic group and 86% in the aortoiliac group. Clinical success, defined as a symptom-free status at the end of follow-up, was also similar in both groups. CONCLUSION: endovascular treatment of isolated aortic lesions of the infra-renal aorta has favorable outcomes comparable to those of aortoiliac lesions. 相似文献
129.
130.
In der Behandlung von Frakturen spielt die Analgesie eine wesentliche Rolle. Es stellt sich daher die Frage, ob in der Klinik h?ufig eingesetzte Analgetika wie Tramadol oder Diclofenac negative Wirkungen auf die Knochenbruchheilung haben. 相似文献