全文获取类型
收费全文 | 2720篇 |
免费 | 152篇 |
国内免费 | 22篇 |
专业分类
耳鼻咽喉 | 28篇 |
儿科学 | 75篇 |
妇产科学 | 85篇 |
基础医学 | 331篇 |
口腔科学 | 343篇 |
临床医学 | 215篇 |
内科学 | 510篇 |
皮肤病学 | 90篇 |
神经病学 | 226篇 |
特种医学 | 40篇 |
外科学 | 284篇 |
综合类 | 10篇 |
一般理论 | 1篇 |
预防医学 | 267篇 |
眼科学 | 43篇 |
药学 | 183篇 |
中国医学 | 40篇 |
肿瘤学 | 123篇 |
出版年
2024年 | 5篇 |
2023年 | 41篇 |
2022年 | 61篇 |
2021年 | 111篇 |
2020年 | 73篇 |
2019年 | 91篇 |
2018年 | 117篇 |
2017年 | 92篇 |
2016年 | 84篇 |
2015年 | 112篇 |
2014年 | 138篇 |
2013年 | 163篇 |
2012年 | 227篇 |
2011年 | 256篇 |
2010年 | 131篇 |
2009年 | 121篇 |
2008年 | 176篇 |
2007年 | 170篇 |
2006年 | 155篇 |
2005年 | 138篇 |
2004年 | 113篇 |
2003年 | 82篇 |
2002年 | 64篇 |
2001年 | 23篇 |
2000年 | 18篇 |
1999年 | 25篇 |
1998年 | 12篇 |
1997年 | 7篇 |
1996年 | 8篇 |
1995年 | 5篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 4篇 |
1991年 | 7篇 |
1990年 | 9篇 |
1989年 | 8篇 |
1988年 | 5篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1985年 | 5篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1976年 | 3篇 |
1969年 | 2篇 |
1968年 | 3篇 |
1967年 | 2篇 |
1965年 | 1篇 |
1932年 | 2篇 |
排序方式: 共有2894条查询结果,搜索用时 15 毫秒
1.
Marina H C G Magalh?es Cristiane Barbosa da Silveira Carla Ruffeil Moreira Marcelo Gusm?o Paraíso Cavalcanti 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,103(6):836-842
Mandibulofacial dysostosis (Treacher Collins Syndrome) is an autosomal dominant genetic disorder that probably derives from inhibition of the facial structures from the first and second branchial arches. The facial pattern of the syndrome is a convex facial profile with a prominent nose above a retruded chin. The eyes are deformed by antimongoloid slant of the palpebral fissures and facial bones are hypoplastic. The alterations are caused by mutation in gene 5q32-33.1, which encodes the nucleolar phosphoprotein treacle. Computed tomography images are able to demonstrate craniofacial bones, allowing the morphological analysis of these bones in individuals with complex deformities. The purpose of this paper is to present the results of a clinical and computed tomography investigation of two patients with Treacher Collins syndrome. 相似文献
2.
3.
T. Stroffolini G. Manzillo R. De Sena E. Manzillo P. Pagliano M. Zaccarelli M. Russo M. Soscia G. Giusti 《European journal of epidemiology》1992,8(4):539-542
Typhoid fever is endemic in the Neapolitan area, where its yearly incidence rate largely exceeds the corresponding national figure. During the period from January to June, 1990, a matched case-control study was carried out in order to identify risk factors of the disease in this area; 51 subjects (mean age 27.2 years) with typhoid fever were compared with 102 controls matched with respect to age, sex and educational level. Consumption of raw shellfish was reported by 76.5% of the cases, as opposed to 19.6% of the controls (P < 0.01). Subjects who had eaten this food item had a 13.3-fold risk (C.I. 95% = 5.5 - 32.8) of contracting typhoid fever. In contrast, no risk was found to be associated with consumption of cooked shellfish, raw vegetables, ice-cream, non-potable water, or unpasteurized milk.The risk factor identified in this study shows that hazardous dietary habits and inadequate sewage treatment facilities, combined with lack of sanitation in the harvesting and marketing of shellfish, play a major role in the endemicity of typhoid fever in the Neapolitan area.Corresponding author. 相似文献
4.
Microinjections of Leu-enkephalin into the dorsal vagal complex induced hypotension and bradycardia. Both naloxone, given at a dose conferring selectivity for μ receptors, and the S antagonist ICI 154,129 prevented the cardiovascular effects of Leu-enkephalin. Naloxone was also found to decrease the gain of the baroreflex. These results suggest that Leu-enkephalin is involved in cardiovascular regulation through activation of δ-, and possibly μ-, opioid receptors in the dorsal vagal complex. 相似文献
5.
Maria De Ftima V. Marques Cristiane A. Henriques Jos Luiz F. Monteiro Sonia M. C. Menezes Fernanda M. B. Coutinho 《Macromolecular chemistry and physics.》1997,198(11):3709-3717
Y zeolites with different sodium contents and a sodium mordenite were evaluated as support for bis(cyclopentadienyl)zirconium dichloride as catalyst for ethylene polymerization. The results showed that, although the activities of the supported catalysts were lower than that of the homogeneous system, the average molecular weight of the polyethylene produced from the former was in general much higher than that of the polymer produced in solution. Contrary to the expected trend if the specific area was the dominant factor for catalyst activity, the best catalyst was the one supported on NaM zeolite. Thus, our results indicate that the concentration of framework aluminium atoms is the dominant factor, but that the contribution of the external surface is also important. 相似文献
6.
7.
Silviene Fabiana De Oliveira Eliane Barbosa Dos Santos Patrícia Jeanne De Souza Mendona Daniela Cristiane Da Cruz Rocha Sidney Emanuel Batista Dos Santos 《American journal of human biology》2001,13(6):718-720
The group‐specific component (GC) system is of interest in anthropological genetic studies because the distribution of its subtypes distinguishes among major ethnic groups. The GC system was analyzed in Curiaú and Pacoval, two remnant Quilombo populations (African‐derived populations) from the Brazilian Amazon. There was no significant statistical difference in allelic frequencies between the two populations or between them and three other African‐derived Brazilian populations (Mimbó, Sítio Velho, and Gaucinha in Northeastern Brazil). These populations share similarities among themselves and with African populations (high frequencies of GC*1F and lower frequencies of GC*1S), which may reflect the influence of a high level of African contribution to their formation, but there is a clear difference between them and Europeans and South American Indians. It is suggested that the GC system is a useful marker for studying relationships between single populations and major ethnic groups, but does not discriminate between populations which share the same parental stock. Am. J. Hum. Biol. 13:718–720, 2001. © 2001 Wiley‐Liss, Inc. 相似文献
8.
9.
Gender-related cytokine patterns in sera of schistosomiasis patients with Symmers' fibrosis 总被引:1,自引:0,他引:1
Silva-Teixeira DN Contigli C Lambertucci JR Serufo JC Rodrigues V 《Clinical and diagnostic laboratory immunology》2004,11(3):627-630
Cytokine levels were compared between schistosomiasis patients affected by intense fibrosis defined by ultrasound examination and graded from F-0 to F-3. The concentrations of interleukin-1beta (IL-1beta), IL-4, IL-5, IL-10, IL-13, gamma interferon, and tumor necrosis factor alpha (TNF-alpha) were determined by enzyme-linked immunosorbent assay of serum samples. Levels of IL-4, IL-5, and TNF-alpha in the sera of F-3 patients were significantly higher than those found in F-0 individuals, while levels of IL-13 were lower. Levels of IL-4, IL-5, and TNF-alpha in serum were significantly higher in F-3 males than in F-0 males or F-3 females. Conversely, levels of IL-13 were significantly lower in F-3 females than in F-0 females and males. 相似文献
10.
Bernardes A Dionísio J Diogo D Coelho P Patrício J 《Surgical and radiologic anatomy : SRA》2005,27(2):79-85
Intraoperative hemostatic suture to treat a bleeding duodenal ulcer is sometimes difficult when there is massive hemorrhage. The aims of this paper are: (1) to describe a practical and easy intraoperative procedure which quickly decreases a massively bleeding duodenal ulcer, allowing the surgeon to identify the bleeding site clearly and obtain definitive hemostasis by suturing the involved vessels with a low risk of common bile duct lesion; and (2) to study in cadavers the anatomical basis of this surgical procedure already successfully performed on patients. Fourteen patients with massive duodenal ulcer bleeding, after unsuccessful endoscopic hemostasis, were operated on and included in this study. After surgical anterior gastroduodenotomy, the surgeon introduced a finger in a downward and forward direction in the bursa omentalis vestibule through the omental foramen. This simple and quick procedure decreased hemorrhage by compressing the gastroduodenal artery against the first part of the posterior surface of the duodenum. Twenty-four fresh blocks of normal tissue were removed from cadavers and were injected with silicone rubber through the common hepatic artery. The distance between the gastroduodenal artery and the omental foramen was measured. With this maneuver the surgeon can clearly see the exact bleeding site and perform an adequate suture with a minor risk of common bile duct lesion. 相似文献