全文获取类型
收费全文 | 123547篇 |
免费 | 8057篇 |
国内免费 | 535篇 |
专业分类
耳鼻咽喉 | 1314篇 |
儿科学 | 3653篇 |
妇产科学 | 2068篇 |
基础医学 | 16410篇 |
口腔科学 | 2211篇 |
临床医学 | 12237篇 |
内科学 | 26108篇 |
皮肤病学 | 1480篇 |
神经病学 | 11964篇 |
特种医学 | 3824篇 |
外国民族医学 | 1篇 |
外科学 | 17737篇 |
综合类 | 1664篇 |
现状与发展 | 1篇 |
一般理论 | 156篇 |
预防医学 | 10794篇 |
眼科学 | 3329篇 |
药学 | 8734篇 |
1篇 | |
中国医学 | 278篇 |
肿瘤学 | 8175篇 |
出版年
2023年 | 610篇 |
2022年 | 1066篇 |
2021年 | 2368篇 |
2020年 | 1411篇 |
2019年 | 2402篇 |
2018年 | 2803篇 |
2017年 | 2041篇 |
2016年 | 2380篇 |
2015年 | 2747篇 |
2014年 | 3960篇 |
2013年 | 5560篇 |
2012年 | 8479篇 |
2011年 | 9097篇 |
2010年 | 4971篇 |
2009年 | 4633篇 |
2008年 | 8033篇 |
2007年 | 8524篇 |
2006年 | 8080篇 |
2005年 | 8134篇 |
2004年 | 7672篇 |
2003年 | 7070篇 |
2002年 | 6820篇 |
2001年 | 1196篇 |
2000年 | 899篇 |
1999年 | 1231篇 |
1998年 | 1455篇 |
1997年 | 1225篇 |
1996年 | 950篇 |
1995年 | 948篇 |
1994年 | 799篇 |
1993年 | 787篇 |
1992年 | 668篇 |
1991年 | 610篇 |
1990年 | 544篇 |
1989年 | 504篇 |
1988年 | 505篇 |
1987年 | 493篇 |
1986年 | 419篇 |
1985年 | 509篇 |
1984年 | 565篇 |
1983年 | 522篇 |
1982年 | 699篇 |
1981年 | 612篇 |
1980年 | 537篇 |
1979年 | 369篇 |
1978年 | 349篇 |
1977年 | 353篇 |
1976年 | 295篇 |
1975年 | 275篇 |
1974年 | 283篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Eric Paul Shaber 《International journal of oral and maxillofacial surgery》1987,16(6):678-681
Recent advances in the field of biomatrix porous implant technology has stirred the interest of the oral and maxillofacial surgical community. One such material (Medpor), is a biocompatible, large-pore, high-density polyethylene implant which has proven both experimentally and clinically to fulfil the criterion for maxillofacial reconstructive and aesthetic surgical grafting. 相似文献
52.
Paul Wexberg MD BM Richard Pacher MD Suzanne Rdler MD Katharina Kiss MD Gilbert Beran MD Michael Grimm MD Gerald Maurer MD Dietmar Glogar MD FESC 《The Journal of heart and lung transplantation》2002,21(12):583-1263
BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation. 相似文献
53.
54.
Peter D. Le Roux David S. Jardine Paul M. Kanev John D. Loeser 《Child's nervous system》1991,7(1):34-39
We reviewed the results of all pediatric patients undergoing intracranial pressure (ICP) monitoring in a 2-year period at our institution. The outcome of patients suffering hypoxia or ischemic injuries (HII) is compared to those suffering non-hypoxic or non-ischemic injuries (NHII). Thirty-four patients had ICP monitors placed during the study period. Inconplete patient information led to the exclusion of 5 patients. An additional 5 patients were excluded because no measures to control ICP were taken after the monitor was placed. Twenty-four patients required treatment for raised ICP (hyperventilation, 24; mannitol, 19; barbiturate coma, 6). Admission Glasgow Coma Score in patients suffering HII (median score 5) and NHII (median score 6) were not significantly different (Mann-Whitney U Test). Only 2 of 8 patients with HII were near-drowning vietims. The remaining 6 had HII from other causes (5 survivors of various forms of asphyxia and 1 of cardiac arrest). All 8 patients had poor outcomes (1 severely disabled; 7 died). The 16 patients with NHII had a variety of diagnoses (6 trauma, 5 encephalitis, 4 bacterial meningitis, 1 diabetic ketoacidosis). Among these, 6 had good outcomes and 10 poor outcomes (2 severely disabled, 2 vegetative, and 6 died). The difference in outcome between patients with NHII and HII is significant at P=0.059 (Fischer Exact test). Patients with NHII may benefit from ICP monitoring. Patients with HII from near-drowning and other causes did not appear to benefit from ICP monitoring and interventions directed at controlling ICP. 相似文献
55.
56.
Katherine A Hillman Tanya M Johnson Paul J D Winyard Geoffrey Burnstock Robert J Unwin Adrian S Woolf 《Experimental nephrology》2002,10(1):34-42
BACKGROUND: Purinergic receptors are cell-surface molecules that bind extracellular nucleotides, notably ATP. The P2X family includes seven nonselective ion channels with one member, P2X(7), implicated in cytolytic pore formation and cell death. MATERIALS AND METHODS: We sought P2X(7) expression in mouse nephrogenesis and cpk/cpk renal cyst growth, conditions in which both proliferation and apoptosis are prominent. RESULTS: P2X(7) immunolocalized to condensed metanephric mesenchyme: both proliferation and apoptosis were detected in this compartment, assessed by proliferating cell nuclear antigen expression and propidium iodide-stained pyknotic nuclei respectively. Later in nephrogenesis, P2X(7) was detected in collecting ducts, a pattern persisting to maturity. A mesenchymal to epithelial shift of P2X(7) expression was also documented in ureter development. In cpk/cpk kidneys, P2X(7)-expressing collecting duct cysts dominated histology from two weeks until four weeks after birth, when animals die from uremia. In polycystic kidneys pyknotic nuclei were rarely identified in P2X(7)-expressing epithelia, but were detected between cysts, consistent with a non-apoptotic role for P2X(7) in cyst enlargement. CONCLUSION: P2X(7) is expressed during normal nephrogenesis and in a model of congenital polycystic kidney disease. Further experiments are necessary to define possible functions of P2X(7) in these settings. 相似文献
57.
Paul Hochstein Ulrich Glatzel Thomas Schmickal Andreas Wentzensen 《Trauma und Berufskrankheit》2002,4(2):s110-s114
The treatment of deep cartilage defects in load-bearing joints is a problem that still has no satisfactory solution. Full-thickness defects of the articular cartilage rarely heal spontaneously, usually leaving damage that can lead to early arthrosis. Techniques currently available for the treatment of chondral defects include abrasion, drilling, micro-fracturing, transplantation of tissue autografts and allografts, and cell transplantation. Osteochondral autograft transplantation is currently the only surgical cartilage repair technique known to lead to the formation of genuine hyaline articular cartilage and its retention at least in the medium term. The Draenert method, in which a water-cooled diamond bone-cutting system is used, is an effective procedure for resurfacing the joints affected by localised cartilaginous defects, even when there is also severe bone loss. Donor-side morbidity can be kept to a minimum by filling the defect caused by harvesting with a press-fit cylinder of cancellous bone covered with periosteum for protection. 相似文献
58.
59.
60.