全文获取类型
收费全文 | 93892篇 |
免费 | 5104篇 |
国内免费 | 239篇 |
专业分类
耳鼻咽喉 | 1132篇 |
儿科学 | 2204篇 |
妇产科学 | 1951篇 |
基础医学 | 12710篇 |
口腔科学 | 3724篇 |
临床医学 | 7235篇 |
内科学 | 22776篇 |
皮肤病学 | 2165篇 |
神经病学 | 8348篇 |
特种医学 | 2286篇 |
外国民族医学 | 1篇 |
外科学 | 12337篇 |
综合类 | 431篇 |
一般理论 | 37篇 |
预防医学 | 8160篇 |
眼科学 | 1734篇 |
药学 | 6429篇 |
中国医学 | 335篇 |
肿瘤学 | 5240篇 |
出版年
2023年 | 578篇 |
2022年 | 538篇 |
2021年 | 1613篇 |
2020年 | 1002篇 |
2019年 | 1678篇 |
2018年 | 2877篇 |
2017年 | 1860篇 |
2016年 | 1953篇 |
2015年 | 2595篇 |
2014年 | 2750篇 |
2013年 | 3896篇 |
2012年 | 7876篇 |
2011年 | 8150篇 |
2010年 | 3802篇 |
2009年 | 2779篇 |
2008年 | 6755篇 |
2007年 | 7001篇 |
2006年 | 6894篇 |
2005年 | 6648篇 |
2004年 | 6015篇 |
2003年 | 5439篇 |
2002年 | 5165篇 |
2001年 | 1975篇 |
2000年 | 2458篇 |
1999年 | 1344篇 |
1998年 | 372篇 |
1997年 | 308篇 |
1996年 | 295篇 |
1995年 | 284篇 |
1994年 | 216篇 |
1993年 | 192篇 |
1992年 | 362篇 |
1991年 | 327篇 |
1990年 | 251篇 |
1989年 | 268篇 |
1988年 | 212篇 |
1987年 | 179篇 |
1986年 | 189篇 |
1985年 | 193篇 |
1984年 | 207篇 |
1983年 | 138篇 |
1982年 | 142篇 |
1981年 | 114篇 |
1980年 | 125篇 |
1979年 | 111篇 |
1978年 | 80篇 |
1977年 | 70篇 |
1976年 | 68篇 |
1974年 | 84篇 |
1973年 | 65篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Gregor Warnecke Murat Avsar Thomas Steinkamp Renate Reinhard Jost Niedermeyer André R Simon Axel Haverich Martin Strüber 《European journal of cardio-thoracic surgery》2005,28(3):454-460
OBJECTIVE: Tacrolimus has been shown to provide superior immunosuppression in various solid organ transplant settings. The purpose of our study was to compare the survival of porcine lung allografts after induction with either cyclosporine A (CsA) or tacrolimus. METHODS: Single lung transplantation from MHC mismatched donors was performed in 10 minipigs. Immunosuppression included 1.5 mg/kg per day methylprednisolone and 1.0 mg/kg per day azathioprine. CsA (n=5) was adjusted to trough levels of 300-500 ng/ml, tacrolimus (n=5) was adjusted to 16-26 ng/ml. All immunosuppressive drugs were discontinued on postoperative day (POD) 28. Allograft survival was monitored by sequential chest radiographs, bronchoscopy and transbronchial biopsy histology. Peripheral blood leukocytes were scanned for donor chimerism and CD3, CD4, CD8 and CD25 expression. RESULTS: The animals survived a 4-week course of immunosuppression without radiological or histological signs of rejection on POD 28. Median allograft survival in CsA-treated animals was 55+/-15 days and all animals rejected their grafts within 42 days after withdrawal of immunosuppression. In tacrolimus-treated animals, median survival was 152+/-65 days with the longest survivor being electively sacrificed on POD 390 (P=0.0064). The degree of donor leukocyte chimerism and the frequency of CD4+CD25+ T-cells were higher in the tacrolimus group, however, these differences were not statistically significant. CONCLUSION: The results of our study show that primary immunosuppression with tacrolimus is superior to cyclosporine after pulmonary allotransplantation in a large animal model. 相似文献
72.
73.
74.
Miguel Marcos Alex Soriano José A Martínez Josep Mensa 《Clinical infectious diseases》2007,45(10):1401; author reply 1401-1401; author reply 1402
75.
Pedro Magno José Loureiro Alexandre Marques Pedro Farto E Abreu Machado Candido Paulo Leal Victor M Gil 《Revista portuguesa de cardiologia》2007,26(10):1033-1042
Ischemic stroke occurs in 0.2-0.4% of patients undergoing left heart catheterization, and is responsible for 5-10% of the mortality associated with the procedure. The main predisposing factors for this complication are female gender, complex atherosclerotic plaques in the ascending aorta, and peripheral arterial disease. The possibility of timely intervention with reperfusion therapy supports close clinical monitoring during the immediate post-catheterization period. The cardiologist should be familiar with the various types of stroke reperfusion therapy and its indications according to the time interval between catheterization and the stroke. The decision should be discussed with neurology and neuroradiology. 相似文献
76.
77.
Reinaldo Figueroa MD Edilberto Martinez MD Raisa P. Fayngersh MD Hong Jiang MD Hatim A. Omar MD Nergesh Tejani MD Michael S. Wolin PhD 《American journal of obstetrics and gynecology》1995,173(6):1800-1806
OBJECTIVE: Our objective was to determine whether the observed relaxation to lactate and other agents in placental vessels of normal pregnancies is altered in severe preeclampsia.STUDY DESIGN: Isolated placental arteries and veins from women with severe preeclampsia and uncomplicated term pregnancies were precontracted with prostaglandin F2α under 5% oxygen and 5% carbon dioxide with the balance nitrogen (Po2 35 to 38 torr) and then exposed to lactate (1 to 10 mmol/L, pH 7.4, n = 8 to 15), arachidonic acid (0.01 to 10 μmol/L, n = 6 to 13), nitroglycerin (1 nmol to 1 μmol/L, n = 4 to 12), or forskolin (0.01 to 10 μmol/L, n = 6 to 9). The response to lactate was also examined in placental vessels from appropriate-for-gestational-age preterm deliveries (n = 8) for comparison with a similar group with severe preeclampsia (n = 8). The t test and analysis of variance statistics were used.RESULTS: Relaxation to lactate was markedly inhibited in both placental arteries and veins of women with severe preeclampsia compared with vessels from uncomplicated term or preterm pregnancies. Responses to the other relaxing agents were not altered in the severely preeclampsia vessels.CONCLUSIONS: In severe preeclampsia absence of lactate-induced dilatation of placental vessels may contribute to the fetal complications associated with impaired blood flow and vasospasm. 相似文献
78.
Auke J. S. Renard Ren P. H. Veth Maciej Pruszczynksi Jaap Hoogenhout Jos Bkkerink Frans J. M. Van Der Staak Theo Wobbes Josef A. M. Lemmens Ren van Hoesel Jim R. Van Horn 《Journal of surgical oncology》1995,60(4):250-256
This paper describes 29 patients with Ewing's sarcoma of bone treated between 1975 and 1990 at the University of Nijmegen Hospital, Nijmegen, The Netherlands. Osteomyelitis was the primary diagnosis in 24%. Treatment consisted of chemotherapy in combination with surgery and/or radiotherapy. Nine patients received radiotherapy only; five of them died of disease. Five patients underwent an intralesional excision; four of them died of disease. Twelve patients underwent a wide excision; there is no evidence of disease in any of them. Three patients underwent a radical disarticulation; all died of disease. The disease-free survival at 1.5 years was 66%. This figure at 5 years was 55%. After wide excision and reconstruction in tumors of expendable, femoral or radial bones good functional results were obtained in all cases. © 1995 Wiley-Liss, Inc. 相似文献
79.
E Díaz-Rubio J Jimeno A Antón E Aranda J Sánchez B Massuti J Cruz-Hernández A Carrato M Martin J Belón 《American journal of clinical oncology》1992,15(1):56-60
One hundred sixty consecutive patients with histologically confirmed colorectal cancer (advanced disease) without prior chemotherapy were entered in a randomized trial comparing 5-fluorouracil (5-FU) 1,000 mg/m2 intravenously per day for 5 consecutive days in continuous infusion versus cisplatin (CP) 100 mg/m2 on day 1 plus 5-FU as described on days 2 to 6. In both arms, treatment was recycled every 4 weeks. Both groups were well balanced for age, sex, colon or rectal origin, median time between diagnosis to advanced disease, performance status at entry, and visceral involvement. The overall response rate in the combination and in the single arm were 18 and 23%, respectively. There were no differences in time to progression (a median of 17.8 and 14.9 weeks for CP-5-FU and 5-FU, respectively) and in overall survival (a median of 71.2 and 59.6 weeks, respectively). The incidence of grade 3-4 emesis was significantly higher in the CP-containing chemotherapy (p = .00001). Our study has failed to demonstrate any clinical benefit from adding cisplatin to 5-FU in patients with cancer of the colon and rectum. 相似文献
80.