全文获取类型
收费全文 | 10273篇 |
免费 | 804篇 |
国内免费 | 105篇 |
专业分类
耳鼻咽喉 | 65篇 |
儿科学 | 442篇 |
妇产科学 | 309篇 |
基础医学 | 1441篇 |
口腔科学 | 198篇 |
临床医学 | 1000篇 |
内科学 | 2426篇 |
皮肤病学 | 138篇 |
神经病学 | 702篇 |
特种医学 | 336篇 |
外科学 | 1381篇 |
综合类 | 185篇 |
一般理论 | 10篇 |
预防医学 | 662篇 |
眼科学 | 265篇 |
药学 | 665篇 |
中国医学 | 97篇 |
肿瘤学 | 860篇 |
出版年
2023年 | 57篇 |
2022年 | 109篇 |
2021年 | 229篇 |
2020年 | 127篇 |
2019年 | 232篇 |
2018年 | 252篇 |
2017年 | 188篇 |
2016年 | 194篇 |
2015年 | 244篇 |
2014年 | 308篇 |
2013年 | 404篇 |
2012年 | 657篇 |
2011年 | 664篇 |
2010年 | 367篇 |
2009年 | 347篇 |
2008年 | 620篇 |
2007年 | 603篇 |
2006年 | 619篇 |
2005年 | 577篇 |
2004年 | 525篇 |
2003年 | 448篇 |
2002年 | 406篇 |
2001年 | 389篇 |
2000年 | 392篇 |
1999年 | 315篇 |
1998年 | 118篇 |
1997年 | 86篇 |
1996年 | 86篇 |
1995年 | 74篇 |
1994年 | 54篇 |
1993年 | 65篇 |
1992年 | 178篇 |
1991年 | 149篇 |
1990年 | 138篇 |
1989年 | 145篇 |
1988年 | 128篇 |
1987年 | 119篇 |
1986年 | 114篇 |
1985年 | 93篇 |
1984年 | 64篇 |
1983年 | 45篇 |
1982年 | 37篇 |
1981年 | 30篇 |
1980年 | 25篇 |
1979年 | 33篇 |
1978年 | 17篇 |
1977年 | 19篇 |
1976年 | 14篇 |
1974年 | 14篇 |
1972年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
The posterior tibial flap is a type C fasciocutaneous flap from the medial calf with the posterior tibial vascular bundle as its pedicle. Most of the skin perforators, 1 to 3 in number, can be found in the middle third of the leg, with an average diameter of 0.8 mm and an average length of 22 mm. The posterior tibial artery ranges between 1.5 and 2.0 mm in diameter, although it is absent in 8 percent of limbs. Since the saphenous nerve is taken with the flap, this is an innervated flap. The flap can be transferred as a free flap or a pedicled flap. The reversed-flow pedicled flap has an average pedicle length of 8 cm. The posterior tibial flap is a reliable, large, thin, innervated flap and can be raised with the patient supine. Case reports are presented of six patients who received a free flap transfer and of one patient who received a reversed-flow pedicled flap. There were two cases of heel ulcerations, two crushed hands, one chronic ulceration and osteomyelitis of the tibia, one burn contracture of the neck, and one salvage flap for diabetic gangrene of the hand. 相似文献
22.
23.
24.
Edward H.C. Wong MRCP Thomas W.H. Leung MRCP K.S. Lawrence Wong FRCP 《Journal of neuroimaging》2007,17(1):87-88
We report a 33-year-old man with seronegative arthritis who had an acute infarct at the left lentiform nucleus while taking etoricoxib and thalidomide regularly. Extensive investigations did not find any evidence of large artery atherosclerosis, vasculitis, cardioembolic source or anti-phospholipid antibodies. While it is possible that a short smoking history, hyperlipidemia, and the use of thalidomide could have contributed to the thrombosis of a small penetrator vessel, we postulated that the prolonged use of etoricoxib is another possible contributing factor. 相似文献
25.
26.
OBJECTIVES: Despite longstanding national guidelines, many children with asthma do not receive annual influenza vaccinations. Information from Medicaid-administrative claims data was integrated into the Michigan Care Improvement Registry (MCIR) to prompt providers regarding influenza vaccination among children with high-risk conditions such as asthma. The attitudes of pediatric primary care providers regarding the implementation of this system were assessed. METHODS: A survey was sent in February 2006 to office-based general pediatricians (n = 300) and family physicians (n = 300) in Michigan. The survey focused on influenza vaccination during the 2005-2006 influenza season and attitudes regarding a reminder system for providers using the MCIR. RESULTS: Overall response rate was 67 percent. MCIR participation was high (91%) among respondents, and most (83%) had MCIR information available to them prior to visits with pediatric patients. Most physicians (75%) considered the MCIR high-risk indicator for influenza vaccination a feature that they would find helpful. Some respondents reported concerns that the reminder system is limited to Medicaid patients only (44%) and regarding the completeness of Medicaid data to identify children with asthma (24%). CONCLUSIONS: Physicians have a positive overall view of a statewide registry-based automated reminder system to assist in identifying children with asthma for influenza vaccination, albeit with specific areas of concern. 相似文献
27.
OBJECTIVES: To evaluate the application of a translated version of an established self-administered questionnaire for carpal tunnel syndrome on Chinese patients in Hong Kong. DESIGN: Evaluation of an instrument tool. SETTING: Department of Orthopaedics and Traumatology, Queen Mary Hospital, Hong Kong; Holistic Medical Centre, Aberdeen, Hong Kong. PARTICIPANTS: Patients with carpal tunnel syndrome, translators. MAIN OUTCOME MEASURES: The adaptation was based on forward-backward translation from English to Chinese (Hong Kong) and vice versa. Meetings with translators, investigators, and patients were organised to generate an acceptable version of the questionnaire. A pilot study was carried out on 20 patients and subsequently minor adjustments were added. Fifty patients were recruited to validate the reliability and internal consistency of the questionnaire. RESULTS: The ordinality of response agreed with the original instrument. Test-retest reproducibility showed no significant difference between tests. The Pearson correlation coefficient ranged from 0.83 to 0.93. Internal consistency was good, at 0.85. CONCLUSION: Through the validation of the Hong Kong Chinese version of the questionnaire, we are able to produce an assessment tool for the local patients. Furthermore, we are able to create a platform for: (i) a cross-national and cross-cultural epidemiological comparison as well as a means of (ii) evaluating different types of treatments. 相似文献
28.
F W Leung E Slodownik D M Jensen G M Van Deventer P H Guth 《Gastrointestinal endoscopy》1987,33(4):284-288
The reflectance spectrophotometric technique measures an index of mucosal hemoglobin concentration and an index of oxygen saturation by spectral analysis of light reflected from the mucosal surface. Using a commercially available unit, a technique for obtaining reproducible endoscopic measurements with acceptable intraobserver and interobserver variability was developed in the anesthetized dogs. The reflectance spectrophotometric finding that experimentally induced prehepatic portal hypertension did not affect gastric mucosal blood flow was confirmed by hydrogen gas clearance measurements. Endoscopic studies in patients with active duodenal ulcer disease revealed a higher index of mucosal hemoglobin concentration and a normal index of oxygen saturation (i.e., an increase in blood flow) at the margin of the ulcer compared with the adjacent normal appearing mucosa. 相似文献
29.
30.
The liver is distinguished from other tissues by (a) its detoxifying function, (b) its resistance to apoptosis, and (c) its regenerative response to damage. Hepatocellular carcinoma arises when chronic insults, such as hepatitis or iron overload, constitutively activate this regenerative program. Here, we propose that the proliferative response of the liver to damage underlies the resistance of hepatocellular carcinoma to cytotoxic therapy, and that hepatocellular carcinoma growth should therefore be more readily controlled by using a networked combination of noncytotoxic interventions to interrupt the damage-inducible regenerative pathway. To this end, hepatocellular carcinoma boasts a wealth of potential drug targets, including viral replication, the antiapoptotic immunosuppressant alpha-fetoprotein, hepatic iron overload, inflammatory signaling, extracellular proteases, and growth factors. By blocking these positive feedback loops in parallel, and so returning the host environment to a more normal state, epigenetic repression of tumor-suppressor gene function may be reversed and tumor dormancy restored. Noncytotoxic maneuvers that short circuit damage resistance loops may thus represent an indirect form of gene therapy meriting incorporation into hepatocellular carcinoma clinical trials. 相似文献