全文获取类型
收费全文 | 2375233篇 |
免费 | 195068篇 |
国内免费 | 4212篇 |
专业分类
耳鼻咽喉 | 34306篇 |
儿科学 | 72756篇 |
妇产科学 | 62940篇 |
基础医学 | 334957篇 |
口腔科学 | 67524篇 |
临床医学 | 215570篇 |
内科学 | 468653篇 |
皮肤病学 | 47933篇 |
神经病学 | 200810篇 |
特种医学 | 96083篇 |
外国民族医学 | 886篇 |
外科学 | 360450篇 |
综合类 | 56221篇 |
现状与发展 | 1篇 |
一般理论 | 977篇 |
预防医学 | 190617篇 |
眼科学 | 55478篇 |
药学 | 177562篇 |
4篇 | |
中国医学 | 4366篇 |
肿瘤学 | 126419篇 |
出版年
2018年 | 24209篇 |
2016年 | 20582篇 |
2015年 | 23289篇 |
2014年 | 33546篇 |
2013年 | 50838篇 |
2012年 | 68754篇 |
2011年 | 72304篇 |
2010年 | 42486篇 |
2009年 | 40885篇 |
2008年 | 68784篇 |
2007年 | 73115篇 |
2006年 | 74012篇 |
2005年 | 72061篇 |
2004年 | 69361篇 |
2003年 | 67027篇 |
2002年 | 66285篇 |
2001年 | 112466篇 |
2000年 | 116550篇 |
1999年 | 98349篇 |
1998年 | 27869篇 |
1997年 | 25530篇 |
1996年 | 25452篇 |
1995年 | 24618篇 |
1994年 | 23167篇 |
1993年 | 21557篇 |
1992年 | 79400篇 |
1991年 | 76399篇 |
1990年 | 73578篇 |
1989年 | 70851篇 |
1988年 | 65852篇 |
1987年 | 64810篇 |
1986年 | 61343篇 |
1985年 | 58409篇 |
1984年 | 44229篇 |
1983年 | 37666篇 |
1982年 | 22891篇 |
1981年 | 20335篇 |
1980年 | 19038篇 |
1979年 | 41307篇 |
1978年 | 28993篇 |
1977年 | 24358篇 |
1976年 | 22839篇 |
1975年 | 23969篇 |
1974年 | 29649篇 |
1973年 | 28053篇 |
1972年 | 26237篇 |
1971年 | 24161篇 |
1970年 | 22760篇 |
1969年 | 21094篇 |
1968年 | 19143篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
151.
152.
153.
G N J Tytgat 《Acta chirurgica. Supplement》2002,(587):77-81
A true comparison of long-term medical and surgical treatment in gastro-oesophageal reflux disease (GORD) is impossible as few studies have been carried out with adequate randomisation of the patients and long-term evaluation of quality of life. In general the control of the reflux symptoms is roughly equal with medical and surgical treatment. However, surgery can cause other symptoms such as dysphagia or non-specific epigastric discomfort or pain in some patients, which reduces the overall efficacy in controlling the symptoms. Based on a cost utility analysis, Heudebert et al. came to the conclusion that medical treatment was their preferred strategy for most patients with severe erosive oesophagitis. 相似文献
154.
Gil Bolotin Frederik H. van der Veen Roberto Lorusso Tamir Wolf Robert Sachner Rona Shofti Jan J. Shreuder Gideon Uretzky 《European journal of cardio-thoracic surgery》2002,21(6):975-980
Objective: Descending and ascending aortomyoplasty are two surgical procedures intended to induce hemodynamic benefits similar to those of the intra-aortic-balloon-pump (IABP). To date, there have been no studies comparing the two surgical techniques. The objective of this study was to compare coronary blood flow augmentation and afterload reduction as produced by descending and ascending aortomyoplasty counterpulsation Methods: Twenty-two mongrel dogs (18–35 kg) underwent IABP application (n=7), descending (n=8), or ascending (n=7) aortomyoplasty. Left anterior descending (LAD) coronary artery blood flow was measured using a Transonic Doppler flow probe. Left ventricular pressure as well as aortic pressures proximal and distal to either the aortomyoplasty site or the IABP position were monitored continuously. Results: Descending aortomyoplasty induced higher elevation in the LAD blood flow during assisted beats (27% from 10.8±4 to 13.8±6 ml/min, P<0.001) than that induced by either ascending aortomyoplasty (19% from 11.7±5 to 14±5 ml/min, P<0.001) or IABP counterpulsation (18% from 8.6±3 to 10.2±4 ml/min, P<0.001). Conversely, while ascending aortomyoplasty reduced the left ventricular end-diastolic pressure by 16% (from 60±18 to 50±22 mmHg, P<0.001), similar to the 16% after load reduction achieved by the IABP counterpulsation, descending aortomyoplasty failed to induce afterload reduction. Conclusions: Descending aortomyoplasty produces higher coronary blood flow augmentation than either ascending aortomyoplasty or IABP. However, afterload reduction comparable to that achieved by IABP was observed only with ascending aortomyoplasty and not with descending aortomyoplasty. 相似文献
155.
156.
The authors studied the cumulative probability of pregnancy for up to 4 consecutive embryo transfer (ET) cycles with ICSI performed for male factor. Transfers could be either fresh or frozen. The clinical pregnancy rate (PR) for the first 4 cycles were similar [44% (61/366); 31% (44/138); 45% (14/31); 44% (4/9)]. Delivery rates were also similar. There was a lower PR on the second retrieval vs. the first retrieval (47% vs. 29%), but this may be related to most of the second retrievals occurring in the second transfer cycle (67%, 31/55); this may be explained by women who were poor responders and required another retrieval without a frozen ET. The majority of transfers in cycle 1 were fresh, whereas cycles 2-4 used primarily frozen-thawed embryos. These data should be helpful for patients requiring IVF with ICSI in deciding to continue with more IVF cycles or consider other 相似文献
157.
J D Woolgar D S Reddy J V Robbs 《European journal of vascular and endovascular surgery》2002,23(3):255-259
OBJECTIVES: to examine the management and outcome of patients with traumatic popliteal artery pseudoaneurysms with delayed presentation. MATERIALS: over a 2-year period 7 patients with traumatic popliteal pseudoaneurysms presenting to a tertiary referral unit after a delay of 1 month were reviewed. METHODS: a retrospective review of clinical records. RESULTS: the median interval between injury and presentation was 1.5 months (range 1-24 months). Penetrating trauma from gunshot wounds was the cause of the initial vascular injury in 6 patients and a stab wound in one. All patients had large pseudoaneurysms of more than 8 cm filling the popliteal fossa with variable degrees of fixed flexion deformity (FFD) of the knee. Severe FFD of more than 40 degrees was noted in 2 patients and 3 others had mild flexion deformities of 10 to 20 degrees. Six patients underwent repair of the pseudoaneurysm. One patient required an above knee amputation due to an infected false aneurysm. There were no deaths or graft related complications. Despite aggressive post-operative physiotherapy only 2 patients were able to completely straighten the leg at the time of discharge. CONCLUSIONS: in patients with neglected popliteal artery pseudoaneurysms, morbidity is associated with the pre-operative degree of fixed flexion deformity of the knee. 相似文献
158.
159.
160.
J?rg Müller Klaus Seppi Nadia Stefanova Werner Poewe Irene Litvan Gregor K Wenning 《Movement disorders》2002,17(5):1041-1045
The frequency and pathophysiology of freezing of gait (FoG) in atypical parkinsonism is unknown. We analysed the frequency of FoG in postmortem-confirmed atypical parkinsonian disorders (APD) comprising corticobasal degeneration (CBD), dementia with Lewy bodies (DLB), multiple system atrophy (MSA), and progressive supranuclear palsy (PSP). Sixty-six patients with pathologically confirmed APD (CBD, n = 13; DLB, n = 14; MSA, n = 15; PSP, n = 24) formed the basis for a multicenter clinicopathological study. Clinical features at first and last clinical visit were abstracted from patient records on standardized forms following strict instructions. At the first visit (median 36 months after symptom onset), 24% of APD had FoG (CBD, 8%; DLB, 21%; PSP, 25%; MSA, 40%). Logistic regression analysis showed a significant association of FoG and urinary incontinence (P = 0.04) at first visit. At last visit, 47% of APD had FoG (CBD, 25%; PSP, 53%; DLB, 54%; MSA, 54%). Clinicopathological correlation based on routine postmortem examination failed to identify a consistent neuropathological substrate of FoG. This study demonstrates that (1) FoG is common in APD, and (2) urinary incontinence is significantly associated with FoG in these disorders. Whether FoG and urinary incontinence share similar neuropathological substrates remains to be determined by future studies. 相似文献