首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   17631篇
  免费   1501篇
  国内免费   289篇
耳鼻咽喉   22篇
儿科学   368篇
妇产科学   17篇
基础医学   2535篇
口腔科学   662篇
临床医学   1656篇
内科学   4807篇
皮肤病学   314篇
神经病学   146篇
特种医学   379篇
外科学   1857篇
综合类   2163篇
现状与发展   3篇
预防医学   473篇
眼科学   110篇
药学   1903篇
  10篇
中国医学   1932篇
肿瘤学   64篇
  2024年   189篇
  2023年   508篇
  2022年   702篇
  2021年   777篇
  2020年   791篇
  2019年   782篇
  2018年   748篇
  2017年   768篇
  2016年   685篇
  2015年   572篇
  2014年   1151篇
  2013年   2082篇
  2012年   835篇
  2011年   922篇
  2010年   655篇
  2009年   781篇
  2008年   738篇
  2007年   779篇
  2006年   633篇
  2005年   522篇
  2004年   470篇
  2003年   328篇
  2002年   345篇
  2001年   282篇
  2000年   254篇
  1999年   249篇
  1998年   249篇
  1997年   188篇
  1996年   184篇
  1995年   157篇
  1994年   139篇
  1993年   137篇
  1992年   111篇
  1991年   80篇
  1990年   82篇
  1989年   59篇
  1988年   52篇
  1987年   57篇
  1986年   62篇
  1985年   49篇
  1984年   52篇
  1983年   31篇
  1982年   53篇
  1981年   38篇
  1980年   22篇
  1979年   16篇
  1978年   15篇
  1977年   12篇
  1976年   11篇
  1975年   10篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
11.
Periodontal conditions in patients with juvenile idiopathic arthritis   总被引:3,自引:0,他引:3  
OBJECTIVE: Our aim was to compare the periodontal conditions in a group of juvenile idiopathic arthritis (JIA) patients with those in a control group of healthy subjects (CTR). MATERIAL AND METHODS: Thirty-two patients with JIA and 24 controls were selected. The measurements used to diagnose periodontal disease included plaque and bleeding scores, probing depths (PDs) and clinical attachment loss (CAL). Laboratory indicators of JIA activity included the erythrocyte sedimentation rate (ESR) and capsule-reactive protein (CRP). The Mann-Whitney test was used to evaluate the data (alpha = 0.05). RESULTS: The mean ages were 15.9 (+/- 2.7) years and 14.7 (+/- 2.3) years for groups JIA and CTR, respectively. The median ESR was 42 mm/h 13 mm/h in the CTR group (p = 0.032) and the median CRP was 1.9 and 0.4 mg/l, respectively (p = 0.001). The prevalence of patients with a proximal attachment loss of 2mm or more in the JIA group was 25% and in controls it was 4.2%. The mean percentages of visible plaque and marginal bleeding were similar in the JIA (54 +/- 22 and 30 +/- 16, respectively) and CTR groups (44 +/- 18 and 29 +/- 11, respectively). The mean percentages of sites with PD > or = 4 mm were significantly higher in the JIA group (3 +/- 4.7) than in the CTR group (0.4 +/- 1.7) (p = 0.012). The mean percentages of sites with proximal CAL > or = 2 mm were 0.7 (+/- 1.4) in the JIA group and 0.001 (+/- 0.2) in the CTR group (p = 0.022). CONCLUSION: Adolescents with JIA present more periodontal attachment loss than healthy controls, in spite of similar plaque and marginal bleeding levels.  相似文献   
12.
The aim of this study was to evaluate the diagnostic accuracy of a well-defined clinical examination for diagnosing anterior disc displacement with and without reduction. A series of 40 patients with temporomandibular disorder (TMD) history were examined according to well-defined routine criteria. This examination included detailed history-taking, standardized clinical head and neck examination that included measurements of the range of motion, palpation of the temporomandibular joints and muscles of mastication for pain and auscultation of joint sounds. Magnetic resonance images of the joints were used as 'gold standard'. Diagnostic accuracy of the clinical examination was 83% for determining normal disc-condyle relationship, 72% for diagnosing anterior disc displacement with reduction, and 81% for diagnosing anterior disc displacement without reduction. Our results suggest that anterior displacement of the disc can be diagnosed with considerable accuracy using a well-defined clinical examination only. Therefore, we conclude that not all patients with TMD symptoms require magnetic resonance imaging examination before treatment.  相似文献   
13.
目的 用透射电镜的方法对两只1月龄健康山羊四只颞下颌关节盘的细胞及胶原结构进行了观察.方法 切取山羊双侧颞下颌关节盘,经组织学处理后行透射电镜观察细胞和胶原超微结构特征.结果 颞下颌关节盘由不均分布的细胞和胶原纤维组成,细胞有成纤维细胞样细胞和软骨细胞样细胞两种,其中成纤维细胞样细胞较软骨细胞样细胞占优势.成纤维细胞样细胞表现有细长的突起,核大,梭形或不规则形,细胞器较少.软骨细胞样细胞胞核呈圆形或椭圆形,周围少有电子透射区,细胞膜不明显,胞突少见.胶原纤维由平行排列的有周期性横纹特征的胶原原纤维组成.结论 颞下颌关节盘细胞有成纤维细胞样和软骨细胞样细胞两种,前者占优势,胶原原纤维表现有周期性横纹特征.这为颞下颌关节盘组织工程研究中细胞来源及表型分析奠定了一定基础.  相似文献   
14.
Modified condylotomy may be relevant in severe painful reciprocal clicking of the temporomandibular joint (TMJ) where conservative treatment is insufficient. The effect of the modified condylotomy was analyzed and compared with conventional nonsurgical treatment in a randomized pilot study of eight patients, 19–44 years of age, with severe painful reciprocal clicking. Before and after treatment, assessments were performed by subjective reports, clinical recordings, and blinded evaluations of radiography and magnetic resonance imaging (MRI). Based on the clinical evaluations before treatment, all conditions were disc displacements with reduction and arthralgia (Research diagnostic criteria for temporomandibular disorders), but based on MRI, one patient had disc displacement without reduction and another had normal disc position. The treatment effect was significantly better and the disorders were significantly more reduced with condylotomy than with conventional nonsurgical treatment (P < 0.05, Mann–Whitney U test). In the surgical group, the clicking and locking had disappeared, the pain during function was significantly reduced (P < 0.05, Friedman ANOVA), and in two patients the disc position was normalized. The clicking still persisted in the nonsurgical patients and the disc position was unchanged. Our conclusion is that modified condylotomy is a promising option to reduce symptoms and signs in severe painful reciprocal clicking.  相似文献   
15.
One hundred and fifty-four adolescents, 76 female and 78 male consented to take part in this survey. The two authors examined and assessed them for dental aesthetics, malocclusion related features and TMJ related signs. The patients were also questioned about their opinion of dental aesthetics, their interest in having orthodontic treatment and their TMJ symptoms. Only 63 per cent of the adolescents who were considered suitable for orthodontic treatment expressed an interest in wanting treatment. Twenty-seven per cent of patients had signs and/or symptoms of TMJ disturbance. No association was found between individual malocclusion problems and TMJ signs and symptoms. The authors considered 56.5 per cent of the total group for orthodontic treatment, the majority for aesthetic reasons, and placed them into high, medium and low priority groups. Fixed appliance therapy for both arches was the recommended type of treatment for most patients.  相似文献   
16.
A study was planned to determine the severity of dental attrition in adults of both sexes in different age groups and its possible relationship to temporomandibular disorders. 500 subjects comprising of 260 females and 240 males in the age group of 18–55 years were clinically examined for bruxism, attrition, and signs of temporomandibular disorders. Tooth sensitivity, tooth or restoration fracture, scalloping of tongue, ridging of buccal mucosa, TMJ sounds, muscle tenderness, TMJ tenderness, referred pain, pain on mouth opening and limitation of mouth opening were recorded along with attrition score in a proforma. The basic data was then analysed to arrive at certain conclusions. A high prevalence of attrition (88.0%) with increase in age (P < 0.00) and was seen more in males as compared to females (P < 0.01). On comparing attrition with some of the signs of bruxism it was shown that tooth or restoration fracture and scalloping of tongue had no relation to the severity of attrition score. Whereas a significant relation was seen between attrition and tooth sensitivity (P < 0.00), and ridging of buccal mucosa (P < 0.05). Muscle tenderness (P < 0.00), pain on mouth opening (P < 0.05) and deviation of mandible on mouth opening (P < 0.00) had significant relation to attrition. Other signs of temporomandibular disorders such as joint tenderness, referred pain, joint sounds and limitation of mouth opening had no relation to attrition score. This study showed a limited association between the severity of attrition and TMJ dysfunction.  相似文献   
17.
18.
Temporomandibular joint (TMJ) condylar cartilage is a distinct cartilage that has both fibrocartilaginous and hyaline-like character, with a thin proliferative zone that separates the fibrocartilaginous fibrous zone at the surface from the hyaline-like mature and hypertrophic zones below. In this study, we compared the effects of insulin-like growth factor-I (IGF-I), basic fibroblast growth factor (bFGF), transforming growth factor beta1 (TGF-β1), and glucosamine sulphate on porcine TMJ condylar cartilage and ankle cartilage cells in monolayer culture. In general, TMJ condylar cartilage cells proliferated faster than ankle cartilage cells, while ankle cells produced significantly greater amounts of glycosaminoglycans (GAGs) and collagen than TMJ condylar cartilage cells. IGF-I and bFGF were potent stimulators of TMJ cell proliferation, while no signals statistically outperformed controls for ankle cell proliferation. IGF-I was the most effective signal for GAG production with ankle cells, and the most potent upregulator of collagen synthesis for both cell types. Glucosamine sulphate promoted cell proliferation and biosynthesis at specific concentrations and outperformed growth factors in certain instances. In conclusion, hyaline cartilage cells had lower cell numbers and superior biosynthesis compared to TMJ condylar cartilage cells, and we have found IGF-I at 100 ng/mL and glucosamine sulphate at 100 μg/mL to be the most effective signals for these cells under the prescribed conditions.  相似文献   
19.
Septic arthritis of the temporomandibular joint (TMJ) is rare and can lead to ankylosis and destruction of the joint. It is usually related to an obvious source of infection, and is often caused by the pathogen Staphylococcus aureus. Prompt treatment results in normal growth and development of the TMJ. In this case report we describe the presentation of a 5 week old neonate with septic arthritis of the knee and TMJ, thought to be related to an infected umbilicus.  相似文献   
20.
AIM: The aim was to compare the prevalence of periodontal conditions in patients with juvenile idiopathic arthritis (JIA) (n=78, age 14.4 years) with those revealed in a healthy control group (n=75, age 15.5 years). MATERIAL AND METHODS: In both groups, the approximal plaque index (API), the modified sulcular bleeding index (SBI), and the clinical attachment loss (CAL) were determined. Laboratory parameters for JIA activity included the capsule-reactive protein (CRP) and the immunoglobulins A, G, M. RESULTS: JIA patients had a significantly higher API (64.6%versus 49.9%, p=0.004) and slightly higher mean percentages of sites with CAL>3.5 mm (0.58%versus 0.22%, p=0.041). There was no significant difference in the prevalence of patients and controls who had sites with CAL >3.5 mm (25.6%versus 17.3%, p=0.212). The mean CAL was slightly greater (0.2 mm; p=0.030) in patients with CRP> or =5.0 mg/l compared with patients with CRP<5.0 mg/l. Patients who took non-steroidal anti-inflammatory drugs (NSAIDs) had a significantly decreased SBI (26.2%versus 51.1%, p=0.019). CONCLUSION: After adjustment for microbial plaque, JIA is not a risk factor for periodontitis.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号