全文获取类型
收费全文 | 4675篇 |
免费 | 221篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 175篇 |
儿科学 | 274篇 |
妇产科学 | 145篇 |
基础医学 | 292篇 |
口腔科学 | 325篇 |
临床医学 | 396篇 |
内科学 | 1107篇 |
皮肤病学 | 73篇 |
神经病学 | 204篇 |
特种医学 | 221篇 |
外科学 | 977篇 |
综合类 | 31篇 |
一般理论 | 2篇 |
预防医学 | 97篇 |
眼科学 | 194篇 |
药学 | 208篇 |
中国医学 | 9篇 |
肿瘤学 | 192篇 |
出版年
2024年 | 3篇 |
2023年 | 70篇 |
2022年 | 87篇 |
2021年 | 158篇 |
2020年 | 89篇 |
2019年 | 120篇 |
2018年 | 129篇 |
2017年 | 114篇 |
2016年 | 197篇 |
2015年 | 242篇 |
2014年 | 277篇 |
2013年 | 343篇 |
2012年 | 451篇 |
2011年 | 401篇 |
2010年 | 205篇 |
2009年 | 176篇 |
2008年 | 294篇 |
2007年 | 357篇 |
2006年 | 259篇 |
2005年 | 228篇 |
2004年 | 215篇 |
2003年 | 169篇 |
2002年 | 187篇 |
2001年 | 31篇 |
2000年 | 29篇 |
1999年 | 28篇 |
1998年 | 19篇 |
1997年 | 11篇 |
1996年 | 5篇 |
1995年 | 4篇 |
1994年 | 5篇 |
1993年 | 5篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有4922条查询结果,搜索用时 15 毫秒
1.
2.
3.
Oral Saygun Serdar Topaloglu Fatih M Avsar Hakan Ozel Sema Hucumenoglu Mustafa Sahin Suleyman Hengirmen 《Canadian journal of surgery》2006,49(2):107-112
BACKGROUND: Most duodenal injuries are managed with primary repair, but the degree of duodenal-wall injury may threaten the integrity of the primary repair. Therefore, we evaluated whether the primary repair site could be reinforced with histoacryl glue (HAG) or HAG with an expanded polytetrafluoroethylene (ePTFE) mesh. METHODS: Grade 3 duodenal injury in the second portion of the rat duodenum was chosen as a standard trauma model. Thirty-three male rats were divided into sham (n = 3), 2-layer primary repair (n = 10), 1-layer primary repair plus HAG application (n = 10) and ePTFE attached with HAG over the 1-layer primary repair site (n = 10) groups. Ten-day survival, adhesion grades and histological assessment were taken as outcome measures. RESULTS: A significant survival advantage was identified in the group that had an ePTFE graft attached with HAG over a 1-layer repair when compared with the group that had a 2-layer primary repair. Adhesion grades were found to be particularly increased in the group that had an ePTFE graft attached with HAG over the primary repair site, moderately increased in the primary repair plus HAG application group and lower in the 2-layer primary repair group. ePTFE graft application was found to be beneficial to coverage of the HAG-dependent empty spaces in the serosal layer. CONCLUSIONS: A primary repair site after duodenal trauma or a difficult duodenal stump can be reinforced with the application of HAG or ePTFE graft implantation with HAG. 相似文献
4.
Yaprak Engin-Ustün Yusuf Ustün M Mutlu Meydanli Ay?e Kafkasli 《Gynecological endocrinology》2006,22(12):676-679
AIM: To compare the effects of 17beta-estradiol given intranasally (intranasal E2) and raloxifene on serum lipid profile and fibrinogen in hypercholesterolemic postmenopausal women. METHODS: The study population consisted of 46 women after menopause. The placebo group (n = 11) was given calcium, while the intervention groups were given intranasal E2 (Aerodiol; Servier, Chambray-les-Tours, France) (n = 16) or raloxifene (Evista; Lilly SA, Madrid, Spain) (n = 19). Blood lipids and fibrinogen were compared between groups at baseline and after 3 months of treatment. RESULTS: The group receiving intranasal E2 showed a significant decrease in triglyceride levels (p<0.05) and a marked increase in high-density lipoprotein cholesterol levels (p<0.05). No changes in lipid profile were observed in the raloxifene and placebo groups. Raloxifene caused a significant decrease in fibrinogen levels (p<0.05). CONCLUSION: Intranasal E2 exerts significant effects on lipid profile in hypercholesterolemic postmenopausal women. Raloxifene has a greater impact on fibrinogen than intranasal E2 application. 相似文献
5.
Fatih Arikan Ali Gürkan 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,103(4):452-457
OBJECTIVE: To introduce 1,1,1,2 tetrafluoroethane (TFE), as a new material for cryosurgery of gingival melanin pigmentation (GMP). STUDY DESIGN: Twenty-one patients with GMP were treated using a TFE-cooled cotton swab. Standard digital images of pigmented areas were measured preoperatively and postoperatively with image-analyzing software. The Mann-Whitney U test was used for statistical analysis. RESULTS: Keratinization was completed 3 to 4 weeks after application, without any trace of pigmentation. Statistical analysis revealed a significant difference between preoperative and postoperative measurements of pigmented areas (P < .05). During the follow-up period, no side effects were observed and improved esthetics were maintained up to month 30. CONCLUSIONS: The clinical outcomes of cryosurgery with TFE for treatment of GMP are very satisfactory. The use of TFE for cryosurgical treatment of GMP is practical and inexpensive. Moreover, unlike other cryosurgery methods no special equipment is required, and it is safe to store in the dental clinic. 相似文献
6.
H Gunen S S Hacievliyagil O Yetkin G Gulbas L C Mutlu E In 《The European respiratory journal》2007,29(4):660-667
The present study was designed to evaluate the hypothesis that nebulised budesonide (NB) might be an alternative to systemic corticosteroids (SC) in the treatment of patients with exacerbations of chronic obstructive pulmonary disease (ECOPD). Patients hospitalised with ECOPD (n = 159) were randomised into three groups. Group 1 received only standard bronchodilator treatment (SBDT), group 2 received SC (40 mg prednisolone) plus SBDT, and group 3 received NB (1,500 microg q.i.d.) plus SBDT. Improvement during 10-day hospitalisation was compared with exacerbation and rehospitalisation rates after discharge. While mean+/-sd age was 64.1+/-8.9 yrs (female/male = 0.1), mean forced expiratory volume in one second (FEV(1)) at admission was found to be 37.2+/-12.2% predicted. Arterial blood gases and spirograms recovered faster in groups 2 and 3. While improvements in arterial oxygen tension (P(a,O(2))) and forced vital capacity (FVC) in group 2, and improvements in P(a,O(2)), FVC and FEV(1) in group 3, became significant at 24-h control, the first significant improvement in group 1 appeared in arterial oxygen saturation at 72-h control. The mean improvement of P(a,O(2)) after 10 days was 1.20 and 1.06 kPa (9 and 8 mmHg) higher in group 2 and 3, respectively, than in group 1. Blood glucose exhibited an upward trend only in group 2. The study demonstrates that nebulised budesonide may be an effective and safe alternative to systemic corticosteroids in the treatment of exacerbations of chronic obstructive pulmonary disease. 相似文献
7.
Sheetal Chopra Anna S Lev-Toaff Fatih Ors Diane Bergin 《Journal of ultrasound in medicine》2006,25(5):617-27; quiz 629
OBJECTIVE: The purpose of this presentation is to show the imaging findings of the common and uncommon variants of adenomyosis as seen on sonography and magnetic resonance imaging (MRI). METHODS: A 3-year database search was performed to identify women who had pelvic sonography and pelvic MRI within a 6-month interval. Images of these cases were retrospectively reviewed. RESULTS: Eighty women were identified. Adenomyosis was diagnosed on MRI, which was used as the reference standard, in 45 of these women. The correct diagnosis was made on sonography in 73% of the cases. CONCLUSIONS: Awareness of the spectrum of imaging features of adenomyosis is important to use sonography effectively for diagnosing this entity and to help avoid misdiagnosis. 相似文献
8.
Spatial analysis of (90)Sr artificial radionuclide in consequence of global fallout and Chernobyl nuclear accident has been carried out by using the point cumulative semivariogram (PCSV) technique based on 40 surface water station measurements in Keban Dam Lake during March, April, and May 2006. This technique is a convenient tool in obtaining the regional variability features around each sampling point, which yields the structural effects also in the vicinity of the same point. It presents the regional effect of all the other sites within the study area on the site concerned. In order to see to change of (90)Sr, the five models are constituted. Additionally, it provides a measure of cumulative similarity of the regional variable, (90)Sr, around any measurement site and hence it is possible to draw regional similarity maps at any desired distance around each station. In this paper, such similarity maps are also drawn for a set of distances. (90)Sr activities in lake that distance approximately 4.5 km from stations show the maximum similarity. 相似文献
9.
Effect of surface conditioning methods on the bond strength of luting cement to ceramics 总被引:9,自引:0,他引:9
OBJECTIVES: This study evaluated the effect of three different surface conditioning methods on the bond strength of a Bis-GMA based luting cement to six commercial dental ceramics. METHODS: Six disc shaped ceramic specimens (glass ceramics, glass infiltrated alumina, glass infiltrated zirconium dioxide reinforced alumina) were used for each test group yielding a total number of 216 specimens. The specimens in each group were randomly assigned to one of the each following treatment conditions: (1) hydrofluoric acid etching, (2) airborne particle abrasion, (3) tribochemical silica coating. The resin composite luting cement was bonded to the conditioned and silanized ceramics using polyethylene molds. All specimens were tested at dry and thermocycled (6.000, 5-55 degrees C, 30 s) conditions. The shear bond strength of luting cement to ceramics was measured in a universal testing machine (1 mm/min). RESULTS: In dry conditions, acid etched glass ceramics exhibited significantly higher results (26.4-29.4 MPa) than those of glass infiltrated alumina ceramics (5.3-18.1 MPa) or zirconium dioxide (8.1 MPa) (ANOVA, P<0.001). Silica coating with silanization increased the bond strength significantly for high-alumina ceramics (8.5-21.8 MPa) and glass infiltrated zirconium dioxide ceramic (17.4 MPa) compared to that of airborne particle abrasion (ANOVA, P<0.001). Thermocycling decreased the bond strengths significantly after all of the conditioning methods tested. SIGNIFICANCE: Bond strengths of the luting cement tested on the dental ceramics following surface conditioning methods varied in accordance with the ceramic types. Hydrofluoric acid gel was effective mostly on the ceramics having glassy matrix in their structures. Roughening the ceramic surfaces with air particle abrasion provided higher bond strengths for high-alumina ceramics and the values increased more significantly after silica coating/silanization. 相似文献
10.
BACKGROUND: Middle ear pathology, either otitis media with effusion or
tubal dysfunction, is frequently seen in day-care centre children.
Recognition and early treatment of this condition is crucial to the
prevention of chronic otitis media, which is a major cause of hearing loss
in later life. OBJECTIVES: We aimed to reveal the incidence of silent
otitis media in day-care centre children and to determine the predisposing
factors, risk factors and the awareness of the parents of the middle ear
disease of their children. METHOD: Two hundred and thirteen children, aged
3-6 years, were screened in four daycare centres. A questionnaire was
prepared that would reveal the predisposing factors. Information was
gathered from both the parents and teachers. Children were examined by
otoscopy, pneumotoscopy, tympanometry and X-rays for sinus pathology.
RESULTS: Forty-three of 213 children had middle ear pathology; 39 of them
were confirmed by tympanometry; 56.1 % of children had some degree of sinus
pathology. We revealed that, although most of the children do not have the
risk factors, they develop middle ear pathology. Among the parents, 81.4%
of them were unaware of the condition. CONCLUSION: Early diagnosis of
middle ear pathologies is necessary for prevention of future complications.
In early stages the condition is silent. We emphasize the importance of the
primary care physician's role in diagnosing the early stages of middle ear
pathologies and recommend that teaching of otoscopic and pneumotoscopic
skills should be part of the training for family physicians.
相似文献