全文获取类型
收费全文 | 8185篇 |
免费 | 757篇 |
国内免费 | 67篇 |
专业分类
耳鼻咽喉 | 32篇 |
儿科学 | 252篇 |
妇产科学 | 211篇 |
基础医学 | 1427篇 |
口腔科学 | 1235篇 |
临床医学 | 771篇 |
内科学 | 701篇 |
皮肤病学 | 55篇 |
神经病学 | 1231篇 |
特种医学 | 111篇 |
外国民族医学 | 1篇 |
外科学 | 404篇 |
综合类 | 447篇 |
预防医学 | 938篇 |
眼科学 | 82篇 |
药学 | 532篇 |
1篇 | |
中国医学 | 109篇 |
肿瘤学 | 469篇 |
出版年
2023年 | 157篇 |
2022年 | 141篇 |
2021年 | 365篇 |
2020年 | 362篇 |
2019年 | 356篇 |
2018年 | 319篇 |
2017年 | 361篇 |
2016年 | 327篇 |
2015年 | 328篇 |
2014年 | 476篇 |
2013年 | 899篇 |
2012年 | 476篇 |
2011年 | 451篇 |
2010年 | 330篇 |
2009年 | 369篇 |
2008年 | 332篇 |
2007年 | 330篇 |
2006年 | 302篇 |
2005年 | 270篇 |
2004年 | 214篇 |
2003年 | 165篇 |
2002年 | 176篇 |
2001年 | 136篇 |
2000年 | 111篇 |
1999年 | 87篇 |
1998年 | 90篇 |
1997年 | 89篇 |
1996年 | 75篇 |
1995年 | 73篇 |
1994年 | 58篇 |
1993年 | 61篇 |
1992年 | 60篇 |
1991年 | 58篇 |
1990年 | 45篇 |
1989年 | 48篇 |
1988年 | 46篇 |
1987年 | 42篇 |
1986年 | 49篇 |
1985年 | 47篇 |
1984年 | 58篇 |
1983年 | 33篇 |
1982年 | 37篇 |
1981年 | 34篇 |
1980年 | 20篇 |
1979年 | 27篇 |
1978年 | 23篇 |
1977年 | 17篇 |
1976年 | 24篇 |
1974年 | 8篇 |
1973年 | 13篇 |
排序方式: 共有9009条查询结果,搜索用时 31 毫秒
91.
Broadbent JM Williams KB Thomson WM Williams SM 《Journal of clinical periodontology》2006,33(11):803-810
BACKGROUND: Dental caries and restorations in proximal tooth surfaces often impinge upon the periodontal biological width. AIM: This study examines whether these factors may contribute to risk for periodontal attachment loss at these sites. METHODS: The study is based upon data from the Dunedin Multidisciplinary Health and Development Study, a long-standing cohort study. Approximal tooth surfaces of 884 study members were evaluated for restorations and caries at age 26 and again at 32 years, and probing depth and gingival recession were recorded in millimetres at age 32. Attachment loss was computed as the sum of pocket depth and gingival recession. Data were analysed using generalized estimating equations. RESULTS: Where a caries/restorative event had occurred on an inter-proximal tooth surface before age 26, the age-32 attachment loss at the corresponding periodontal site was approximately twice more likely to be >or=3 mm than if the adjacent tooth surface had remained sound to age 32. This was also true where a caries/restorative event had occurred subsequent to age 26. The association remained after controlling for potential confounders, including smoking. CONCLUSIONS: Site-specific periodontal attachment loss due to dental caries or restorative events occurs in adults in their third and fourth decades of life. 相似文献
92.
Miranda LA Fischer RG Sztajnbok FR Figueredo CM Gustafsson A 《Journal of clinical periodontology》2003,30(11):969-974
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
93.
G. Nethander 《Journal of periodontal research》1994,29(4):250-258
Inflammatory reactions of the marginal periodontal tissues and loss of attachment could partly account for the often occurring rejection of autogenously transplanted mature teeth. The periodontal conditions of transplanted teeth were investigated from 1 month up to 5 years postoperatively. The parameters plaque, bleeding on probing to the bottom of the pocket, probing pocket depth (PPD), gingival recession and probing attachment loss were analysed by multiple regression analysis. No significant difference was found between transplanted and control teeth in bleeding on probing the bottom of the pockets up to 5 years postoperatively with the exception of increased bleeding on probing of the transplanted teeth at the 1-month postsurgery examination. No significant difference of the mean probing depth between transplanted teeth and control teeth was found at the mesio- and distobuccal surfaces. The transplanted teeth at the buccal surface showed increase of the mean pocket depth during the observation period. Increased mean probing depth without progression over time was found at the transplanted teeth compared to the controls at the distolingual, lingual and mesiolingual surfaces. A small mean gingival recession at the transplants was observed. Loss of attachment was recorded at 13% of the surfaces. Totally 50% of the transplants showed loss of attachment and 5% were removed because of extensive attachment loss. On 13% of the transplanted teeth with loss of attachment, root resorption was also found. 相似文献
94.
Relationship between smoking and dental status in 35-, 50-, 65-, and 75-year-old individuals 总被引:4,自引:0,他引:4
Abstract. The aim of the present study was to examine the dental status and smoking habits in randomized samples of 35-, 50-, 65-, and 75-year-old subjects (n= 1093), recruited for a cross-sectional epidemiological study in the County of Värmland, Sweden. The following clinical variables were recorded by 4 well-calibrated dentists: number of edentuolous subjects, number of missing teeth, probing attachment level, furcation involvement, CPITN scores, DMF surfaces, plaque and.stimulated salivary secretion rate (SSSR). In addition, the subjects reported in a questionnaire their tobacco habits, oral hygiene habits, dietary habits etc. The percentage of smokers in 35-, 50-, 65-, and 75-year-olds was 35%, 35%, 24% and 12%, respectively. In 75-year-olds, 41% of the smokers were edentulous compared to 35% of non-smokers. The difference in number of missing teeth between smokers and non-smokers was 0.6 (p=0.15), 1.5 (p=0.013), 3.5 (p=0.0007) and 5.8 (p=0.005) in the 4 age groups. Smokers had the largest mean probing attachment loss in all age groups. The differences between smokers and non-smokers in mean attachment level were 0.37 (p=0.001), 0.88 (p=0.001), 0.85 (P=0.001) and 1.33 mm (p=0.003) in the 35-, 50-, 65-, and 75-year-olds, respectively. Treatment need assessed by CPITN was in all age groups greatest among smokers. The number of intact tooth surfaces was fewer in 35-, 50-, and 75-year-old smokers than in non-smokers. The number of missing surfaces (MS) was higher in 50-, 65-, and 75-year-old smokers than in non-smokers. In addition, 35-year-old smokers exhibited a significantly larger number of decayed and filled tooth surfaces (DFS) than non-smokers. Male smokers had significantly higher SSSR than non-smoking males (p=0.012). Plaque index and oral hygiene were similar in smokers and non-smokers. Smokers reported a more frequent intake of sugar containing soft drinks (p=0.000) and snacks (p=0.003) than non-smokers. The opposite was reported for consumption of fruit (p=0.003). It was concluded that smoking is a significant risk indicator for tooth loss, probing attachment loss and dental caries. 相似文献
95.
Attachment loss with postmenopausal age and smoking 总被引:1,自引:0,他引:1
C. F. Hildebolt T. K. Pilgram M. Dotson N. Yokoyama-Crothers J. Muckerman J. Mauser S. Cohen E. Kardaris M. W. Vannier P. Hanes M. K. Shrout R. Civitelli 《Journal of periodontal research》1997,32(7):619-625
To determine whether postmenopausal bone loss and factors associated with osteoporosis affect tooth retention, we examined vertebral and proximal femoral (postcranial) bone mineral density in relation to tooth loss and attachment loss in a cross-sectional study of 135 postmenopausal women (age range 41–70 yr). Women had at least 10 teeth and no evidence of moderate or severe periodontal disease. Full-mouth attachment loss measurements were made using a pressure-sensitive probe, and bone density was determined by dual-energy X-ray absorptiometry. Attachment loss was correlated with tooth loss (number of remaining teeth, radiologically determined), but not with vertebral or proximal femur bone density. Multivariate analysis showed current smoking (p = 0.01), years since menopause (p = 0.02) and the interaction of age and current smoking (p < 0.01), to be statistically significant predictors of attachment loss in our study population. 相似文献
96.
目的:研究热处理对磁性附着体固位力的影响。方法:磁性附着体Magfit EX 400W型、Magfit EX 600 W型和Magfit EX 800W型各10个试件,通过模具固定在万能力学试验机的测试台上,测试其固位力,然后将磁性附着体经过水浴热处理,再次进行固位力测试。采用SPSS11.0软件包对数据进行统计学分析。结果:磁性附着体Magfit EX400W型、Magfit EX 600W型和Magfit EX 800W型的初始固位力测量值分别为(1.64±0.11)N、(2.67±0.19)N和(3.02±0.25)N;经热处理后,其固位力测量值分别为(1.58±0.12)N、(2.65±0.14)N和(3.02±0.24)N。热处理前、后,其固位力无显著差异(P>0.05)。结论:磁性附着体的磁体部分可进行水浴热处理以减少单体,而其固位力无显著改变。 相似文献
97.
Probe penetration in relation to the connective tissue attachment level: influence of tine shape and probing force 总被引:2,自引:1,他引:2
Hankie M. Bulthuis Dick S. Barendregt Mark F. Timmerman Bruno G. Loos Ubele van der Velden 《Journal of clinical periodontology》1998,25(5):417-423
Abstract. Previous research has shown that probing force and probe tine shape influence the clinically assessed probing depth. The purpose of the present study was to investigate the effect of tine shape and probing force on probe penetration, in relation to the microscopically assessed attachment level in untreated periodontal disease. In 22 patients, scheduled for partial or full mouth tooth extraction and no history of periodontal treatment, 135 teeth were selected. At mesial and distal sites of the teeth reference marks were cut. Three probe tines, mounted in a modified Florida Probe® handpiece, were tested: a tapered, a parallel and a bail-ended; tip-diameter 0.5 mm. The three tines were distributed at random over the sites. At each site increasing probing forces of 0.10 N, 0.15 N, 0.20 N, 0.25 N were used. After extraction, the teeth were cleaned and stained for connective tissue fiber attachment. The distance between the reference mark and the attachment level was determined using a stereomicroscope. The results showed that the parallel and ball-ended tine measured significantly beyond the microscopically assessed attachment level at all force levels; with increasing forces, the parallel tine measured 0.96 to 1.38 mm and the ball-ended tine 0.73 to 1.06 mm deeper. The tapered tine did not deviate significantly from the microscopic values at the forces of 0.15. 0.20 and 0.25 N. It can be concluded that for the optimal assessment of the attachment level in inflamed periodontal conditions, a tapered probe with a tip diameter of 0.5 mm and exerting a probing force of 0.25 N may be most suitable. 相似文献
98.
目的:评估阻生智齿拔除患者牙科焦虑症与特质焦虑的关系,为拔除阻生智齿前进行心理治疗和心理护理提供指导。方法:采用Corah’s的牙科焦虑量表(DAS),凯氏牙科畏惧调查量表(DFS),状态一特质焦虑问卷(STAI)。特质焦虑由STAI的特质焦虑问卷(TAI)量度。对60个患者进行横断面调查,然后对各量表的分值进行相关性分析。结果:特质焦虑与DAS,DFS的分值有显著相关性。3种调查方法相互之间有显著相关性。在特质焦虑调查中,性别差异唯一有统计学意义。结论:阻生智齿拔除患者牙科焦虑症与特质焦虑相关,拔牙前进行心理治疗和心理护理是必要的。 相似文献
99.
Aloufi F Bissada N Ficara A Faddoul F Al-Zahrani MS 《Clinical implant dentistry and related research》2009,11(1):37-40
Purpose: This retrospective study assessed the health of peri-implant tissues in patients with varying severity of chronic periodontitis.
Materials and Methods: Sixty-one subjects aged 44 to 70 years (median age 58 years) were recruited. Based on severity of periodontitis, 31 subjects were classified as having severe generalized chronic periodontitis, and the remaining 30 subjects had mild or no periodontitis. Social and medical histories were obtained from each patient. A comprehensive periodontal examination included: plaque index, gingival index, bleeding index, probing depth, clinical attachment level, and radiographic bone loss. Data were analyzed using Fisher's exact and chi-square tests for categorical variables, and t -test for continuous variables.
Results: There was a statistically significant greater loss of attachment ( p < .05) around implants in the group with severe periodontitis compared to the no/mild periodontitis group.
Conclusion: Because of the greater loss of clinical attachment around implants placed in patients with generalized severe chronic periodontitis, close monitoring of these patients is suggested to prevent both development of peri-implantitis and recurrence of periodontal infection. 相似文献
Materials and Methods: Sixty-one subjects aged 44 to 70 years (median age 58 years) were recruited. Based on severity of periodontitis, 31 subjects were classified as having severe generalized chronic periodontitis, and the remaining 30 subjects had mild or no periodontitis. Social and medical histories were obtained from each patient. A comprehensive periodontal examination included: plaque index, gingival index, bleeding index, probing depth, clinical attachment level, and radiographic bone loss. Data were analyzed using Fisher's exact and chi-square tests for categorical variables, and t -test for continuous variables.
Results: There was a statistically significant greater loss of attachment ( p < .05) around implants in the group with severe periodontitis compared to the no/mild periodontitis group.
Conclusion: Because of the greater loss of clinical attachment around implants placed in patients with generalized severe chronic periodontitis, close monitoring of these patients is suggested to prevent both development of peri-implantitis and recurrence of periodontal infection. 相似文献
100.
Haim Tal Michael Soldinger Areyh Dreiangel Sandu Pitaru 《Journal of clinical periodontology》1989,16(10):654-659
The combined length of the supracrestal connective tissue attachment and the junctional epithelium is referred to as the "biologic width". The long-term (1-year) effect of complete violation of the supracrestal connective tissue attachment was examined in beagle dogs. Full thickness periodontal flaps were elevated, exposing the buccal bony crests of the maxillary and mandibular canines of 3 beagle dogs. The roots of the experimental teeth were planed and class V cavities were prepared. The apical border of each cavity was located at the alveolar bone crest. The cavities were restored with amalgam and the flaps were repositioned and sutured. In the control sites, a notch was prepared at the CEJ and the distance between the notch and the bony crest was measured. The dogs were sacrificed 57 weeks after the operation and the experimental and control sites prepared for histologic analysis. Every 5th section was examined and measurements were taken of the amount of gingival and bone recession, the length of the connective tissue and the epithelial attachment. Control sites healed uneventfully. Gingival recession averaged only 0.5 mm; bone loss was minimal and averaged 0.15 mm. The combined length of the supracrestal connective tissue and epithelial attachment measured 4.47 mm. In experimental sites, the gingiva receded 3.16 mm on average. Moderate bone loss (mean = 1.17 mm) was noted, but no signs of bone resorption were seen at the time of sacrifice. After bone loss, root surfaces which were previously attached to alveolar bone by periodontal ligament were mainly (0.90 mm) attached to connective tissue.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献