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1.
Evidence suggests that asymmetry in frontal electrical activity predicts responses to aversive experiences, such that higher left‐sided activity might dampen responses to trauma reminders. We measured frontal asymmetry at rest and during viewing of a trauma film, and assessed startle responses to film‐reminder images. To explore potential moderators, we compared two films (Study 1; N = 64) and modulated reappraisal (Study 2; N = 72). As expected, left frontal activation during film viewing predicted dampened responses in individuals who viewed a staged road accident. However, this effect tended to be reversed when a genocide documentary was used. In Study 2, all participants viewed the genocide film. Left frontal activity at rest again predicted higher startle responses, while reappraisal did not moderate the effects. Thus, the type of trauma film plays a crucial role in the effects of frontal asymmetry, which warrants further critical investigation.  相似文献   
2.
The Institute of Food Science and Technology is this year celebrating 50 years since its formation. But we are not planning a year of retrospection – far from it. The main focus for the Institute's celebrations is very much on the future, hence the main theme for our 50th Jubilee year; ‘The Fantastic Future of Food’. Food science and technology can provide solutions to many of the current big challenges such as food safety, sustainability, waste reduction and, of course, some aspects of nutritional health. The Institute is therefore using its 50th Jubilee to raise the profile of its activities and also launch a number of key projects which it believes will have a significant impact on some of the key issues facing the food sector. The first of these will be its Register of Food Safety Professionals which will provide independent professional accreditation at all levels for those engaged in food safety roles.  相似文献   
3.
Objective: To systematically assess the informational value, quality, intention, source and bias of web 2.0 footage whose aim is peer‐to‐peer education about oral implantology. Methods: YouTube ( http://www.youtube.com ) was scanned on 15 October 2010 for oral implantology‐related videos using an adequately pre‐defined search query. Search results were filtered with the system‐generated category ‘education’ and the additional criterion ‘most viewed’. Only those videos with at least 1000 views were included (total 124, of which 27 were excluded because they were not related to implantology). Filtered videos were discussed and rated with particular regard to the educational needs of potential groups of addressees [(i) undergraduates and laymen, (ii) dentists without or currently undergoing a specialisation in oral implantology and (iii) dentists who have completed a specialisation in the field of oral implantology] by a jury consisting of (i) an accredited post‐graduate university instructor with 22 years of professional teaching experience in the field of implantology, (ii) a university lecturer in dentistry/orthodontics with 10 years teaching experience and (iii) a university haematologist/oncologist. They were required to fill out a questionnaire for each video. The data were statistically analysed using non‐parametric ANOVA (α = 5%) and a sign test (α = 0.05/3 = 0.017). Results: The YouTube scan produced 1710 results in the category ‘EDU’. The analysis revealed that there is a wide range of instructional footage on this topic, but with highly variable range in quality and informational value. Footage intention was to large proportions (47.4%) a mixture of education and advertisement. Its usefulness differed significantly for the three groups of addressees, offering greater novelty to undergraduates and post‐graduates. Conclusion: YouTube and similar social media websites may have a potential capacity and value in complementing continuing education in the technique of oral implantology. As a means of achieving an acceptable level of knowledge about the topic when used alone, it should not be considered to be suitable at this point in time.  相似文献   
4.

Objectives

The purpose of this study was to perform a finite element analysis to determine whether adhesive reconstruction is able to restore the original biomechanical behaviour of weakened roots, in terms of fracture resistance, when compared with post/crown-restored teeth with intact roots.

Methods

A three-dimensional model of a maxillary central incisor was created. The model simulated an endodontically treated tooth restored with a glass-fibre post, a composite-resin core and a metal crown (Model 1). Based on Model 1, a new volume was created in the root cervical third that represented the area where the dentine structure was lost, resulting in a structurally damaged root (Model 2). A 100 N load was applied to the palatal surface at 130° from the long axis of the tooth. After processing (Ansys® 10.0 – Canonsburg, PA, USA), the principal normal stress data were analyzed (S1, tensile; S3, compressive).

Results

The models demonstrated a similar S1 distribution concentrated in the lingual cervical region but different S1 levels (Model 1: 28.7 MPa; Model 2: 35.3 MPa). The S3 distribution indicated differences in behaviour between the models (Model 1: −18 to −27 MPa along the buccal root surface; Model 2: −25 to −32 MPa on the post buccal surface and along the buccal root wall).

Conclusions

Although the stress distribution within the root walls remained below the ultimate stress limit of the root dentine, the adhesive reconstruction of the weakened roots did not recover the load resistance of structurally intact roots.

Clinical significance

The decision of when to prosthetically rehabilitate weakened roots with cervical dentine structural tissue loss is a challenge for clinicians. A ‘monoblock’ adhesive reconstruction has been proposed for root reinforcement. During treatment planning, the possibility of restoring the mechanical resistance of the root must be evaluated if successful long-term results are to be achieved.  相似文献   
5.

Objectives

To evaluate the effect of the length of fibre-posts1 and type of adhesive cement2 on the fracture resistance of endodontically treated teeth, after fatigue loading.

Methods

Eighty extracted upper pre-molars were sectioned at the CEJ and endodontically treated. After 24 h of water storage at 37 °C, RelyX Posts (3M-ESPE) were cemented with Panavia F 2.0 (Kuraray) or RelyX Unicem (3M-ESPE). A standardized composite core was built. Specimens were divided into four groups depending on the post–core ratio: (A) 2/1 (control); (B) 3/2; (C) 1/1 (small diameter); (D) 1/1(large diameter) and submitted to 1,200,000 cycles using a chewing simulator (Willytech). Immediately afterwards, all specimens that survived fatigue loading were fractured using a universal loading device (Micro-tester, Instron). Data were analysed with ANOVA.

Results

Four percent of the specimens failed during fatigue loading. The length of the post into the root affected the fracture resistance. The statistical outcome varied according to the inclusion of specimens failed during fatigue loading. However, the control group always had the lowest fracture resistance. The type of adhesive cement did not affect the fracture resistance. A prevalence of not-repairable failures was observed in specimens restored with the longest posts, whilst shorter posts led to more repairable failures.

Conclusions

Shortening the post length and the ensuing preservation of more tooth structure, offer the potential for reparability through an in-built fail safe mechanism and may thus reduce the occurrence of catastrophic failures.  相似文献   
6.
The selection of the best restoration for an endodontically treated tooth in the aesthetic zone depends on strength and the ability to recreate the form, function, and aesthetics of the natural tooth. The increased use of all-ceramic materials is a result of improved ceramic materials and adhesive systems. However, the advent of the current variety of translucent ceramic systems makes the shade of the abutment important in achieving the desired aesthetic outcome. This article discusses the different types of posts used in the restoration.  相似文献   
7.
Kelly K 《Nursing forum》2010,45(4):266-270
The DNP is being touted as the answer to the faculty shortage. There is no evidence that DNP graduates are any more willing to embrace the low salaries of nursing faculty than PhD graduates. The idea of the DNP as the answer to the faculty shortage is challenged.  相似文献   
8.
目的探讨三种复合树脂核材料与玻璃纤维桩的微拉伸粘接强度,为临床提供相关病例的治疗依据。方法将45颗健康离体上颌中切牙随机分为3组。根管预备后选用三种粘结剂(可乐丽菲露AP-X、Ceram-X、ParaCore双重固化复合树脂)分别粘结直径1.2mm玻璃纤维桩。将牙沿垂直牙根长轴方向片切成厚度为1mm的薄片。用万能力学实验机进行微推出测试,用体视显微镜观察断裂方式。对粘结强度及断裂类型进行统计学分析。结果 ParaCore与Ceram-X的微拉伸粘结强度显著高于AP-X(P〈0.05),ParaCore和Ceram-X与纤维桩的微拉伸粘结强度没有显著性差异(P〉0.05)。结论 ParaCore和Ceram-X与玻璃纤维桩是适于临床塑核使用的粘结材料,其粘结性能较好。  相似文献   
9.
We describe a comprehensive surveillance system involving infection control practitioners, surgeons, administrative staff, and patients aimed at improving the postdischarge surveillance of surgical site infections. The system was able to detect 22 infections out of 538 procedures, 95% of which were detected during the postdischarge period.  相似文献   
10.
目的 研究海上灾害严重创伤患者创伤后应激障碍(posttraumatic stress disorder,PTSD)水平,并提出有效的防治方法.方法 200例海上灾害严重创伤患者分成治疗组(100例)和对照组(100例),对照组采用常规治疗,包括现场急救、手术和纠正高渗、高钠、高氯血症,纠正酸中毒和抗感染;治疗组在常...  相似文献   
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