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   102882篇
  免费   15739篇
  国内免费   879篇
耳鼻咽喉   2154篇
儿科学   2548篇
妇产科学   2220篇
基础医学   4128篇
口腔科学   4433篇
临床医学   22880篇
内科学   22372篇
皮肤病学   2849篇
神经病学   11471篇
特种医学   3216篇
外科学   15660篇
综合类   286篇
现状与发展   31篇
一般理论   25篇
预防医学   12884篇
眼科学   2015篇
药学   2042篇
  5篇
中国医学   38篇
肿瘤学   8243篇
  2024年   723篇
  2023年   4327篇
  2022年   1349篇
  2021年   2774篇
  2020年   4604篇
  2019年   2228篇
  2018年   6051篇
  2017年   6140篇
  2016年   6711篇
  2015年   6821篇
  2014年   8938篇
  2013年   10485篇
  2012年   4290篇
  2011年   4085篇
  2010年   6154篇
  2009年   7820篇
  2008年   3790篇
  2007年   2871篇
  2006年   3745篇
  2005年   2556篇
  2004年   1923篇
  2003年   1568篇
  2002年   1487篇
  2001年   1593篇
  2000年   1005篇
  1999年   1483篇
  1998年   1751篇
  1997年   1622篇
  1996年   1655篇
  1995年   1437篇
  1994年   927篇
  1993年   804篇
  1992年   657篇
  1991年   598篇
  1990年   477篇
  1989年   482篇
  1988年   457篇
  1987年   354篇
  1986年   314篇
  1985年   295篇
  1984年   256篇
  1983年   289篇
  1982年   233篇
  1981年   207篇
  1980年   141篇
  1979年   91篇
  1978年   114篇
  1977年   134篇
  1976年   116篇
  1974年   92篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Temporalis muscle transfer is a versatile technique frequetly used for reconstructive procedures in the maxillofacial region. However the thickness of the pedicle may interfere with masticatory function when used anteriorly in the oral cavity. To repair full-length mid-palatal defects in fully dentate patients the flap can be passed through the maxillary sinus and combined with local repair of the soft palate, thus avoiding any occlusal trauma from the posterior teeth.
The operation is a single stage procedure with low morbidity and few complications, and is a useful technique for repairing the large untreated clefts frequently encountered in developing countries. The procedure is used by members of the Australian and New Zealand Association of Oral and Maxillofacial Surgeons Bangladesh Project who have operated in Dhaka teaching hospitals on a regular basis since 1991.  相似文献   
72.
Objective. The aim of this study was to determine the feasibility of a novel saliva-activated bioadhesive drug delivery system of lidocaine hydrochloride as a viable alternative to infiltration anesthesia in dentistry.Study design. The study was carried out in three stages. First, the drug delivery system (DDS) was subjectively evaluated for adherence to the gingival mucosa and peak effect of anesthesia. In the second stage, a comparative subjective and objective evaluation of the DDS with a marketed topical gel preparation was carried out. Finally an open label, nonblinded clinical trial was carried out using the exodontia model. A total of 49 extractions were attempted in 41 patients. The effect of the following variables was investigated in the study: (1) jaw (maxillary and mandibular), (2) overall mobility, (3) position-notation of tooth (1, 2, 3, 4…). The positive extractions were statistically analyzed by the t test comparison of means of two independent variables.Results. Subjective evaluation revealed that the DDS adheres to the gingiva within a minute and produces peak effect in 15 minutes. Comparative study revealed that the DDS produces greater depth of anesthesia than the marketed topical gel. Of 49 extractions attempted with the DDS, 40 were successful, giving an efficacy of 81.63%.Conclusion. The novel saliva-activated bioadhesive drug delivery system of lidocaine hydrochloride exhibits potential as a feasible alternative to infiltration anesthesia in dentistry.  相似文献   
73.
Exfoliative cytology is a rapid, non-invasive procedure for assessing dysplastic change within the oral epithelium. The indications for oral exfoliative cytology are reviewed and a technique for cell collection and smear examination is presented. The value of exfoliative cytology in oral cancer screening programmes as a public health measure is discussed.  相似文献   
74.
Preventive Behaviors as Correlates of Periodontal Health Status   总被引:1,自引:0,他引:1  
Objectives: This investigation examined current practices of brushing, flossing, and periodic dental visits and their association with periodontal health status. Methods : Data were collected using face-to-face interviews and 40-minute in-home dental examinations with a probability sample of adults 18 years of age or older, having at least one tooth, and living in housing units in the Detroit tricounty area. Complete examinations were performed on 319 individuals. Results : On average, subjects reported brushing their teeth about twice a day. About one-third of the population reported flossing at least once a day. Loss of periodontal attachment was related to frequency of brushing while subjects who exhibited acceptable flossing ability had less plaque and calculus, shallower pocket depths, and less attachment loss. Subjects reporting a periodic dental visit at least once a year had less plaque, gingivitis, and calculus than subjects reporting less frequent visits. In regression analyses, brushing thoroughness, flossing ability and frequency, and dental visit frequency were predictors of lower plaque, gingivitis, and calculus scores. In turn, these scores were predictors of shallower pocket depths and less attachment loss. Conclusions : Brushing, flossing, and periodic dental visits were correlated with better periodontal health. The behaviors appeared to be indirectly related to pocket depth and attachment loss through their associations with plaque, gingivitis, and calculus levels.  相似文献   
75.
Forty cervical abrasion lesions were restored with a self-cure Type 2A glass ionomer cement. Prior to placement of the restorations, 20 lesions were scrubbed for 15 seconds with 25 per cent polyacrylic acid and 20 lesions were cleaned with a pumice and water slurry on a rubber cup. After three years, there was negligible marginal staining, and one restoration from each group was partly lost. There was no evidence to suggest that polyacrylic acid was preferred to pumice and water in the restoration of cervical abrasion lesions with glass ionomer cement.  相似文献   
76.
In HIV infected patients, a distinct form of gingivitis and periodontitis was reported recently. This paper reviews the clinical and microbiological features of these lesions and makes recommendations regarding their clinical management. The need for early treatment and control of periodontitis in HIV seropositive patients is emphasized.  相似文献   
77.
Comparisons of physical features within identical (monozygous) and non-identical (dizygous) twin pairs have provided valuable insights into the relative contributions of genetic and environmental influences to observed variability. The special nature of the twinning process itself also provides an opportunity to learn more about early human development, including how body symmetry is determined. The mechanisms of twinning, mortality and morbidity in twins, determination of body symmetry including the phenomenon of mirror-imaging, postnatal growth and development of twins, and zygosity determination are discussed. Twin studies with direct relevance to clinical dentistry are reviewed and illustrated by examples from an ongoing investigation of dentofacial morphology in South Australian twins.  相似文献   
78.
Australians may receive free dental treatment via the public sector if they have a health care card but otherwise must seek treatment via the private sector. These two modes of dental delivery have different objectives, facilities, and patient populations. Two groups of patients, one public and one private, who presented to the same clinicians with temporomandibular joint dysfunction were studied. There were differences in age, numbers of natural teeth and some psychological features. However, the outcome to simple non-surgical management resulted in similar levels of successful treatment.  相似文献   
79.
Since 1975, more than 100,000 Indo-Chinese refugees from Vietnam, Kampuchea, and Laos have been resettled in Australia. This dental survey was undertaken to compare the dental health of 104 Australian-born and 126 Indo-Chinese adolescents from a State high school within a high migrant area of Melbourne. The mean DMFT score for the Australian-born group was 3.37 teeth, compared with 6.05 for the Vietnamese group, and 3.10 for the Kampuchean-Laotian group. More restorations and extractions were required by the Vietnamese subjects compared with the Australian-born and Kampuchean-Laotian subjects. Almost all subjects had gingivitis, however the proportion of Indo-Chinese subjects with shallow and deep pockets was greater than that of the Australian-born subjects. The periodontal health of the Kampucheans and Laotians was the most severe of the Indo-Chinese groups. These findings indicate that the Indo-Chinese adolescent refugees represent a high risk group for dental problems within the Australian population.  相似文献   
80.
The history of denture base materials and the accompanying development of impression techniques are traced from the earliest times to the present day (Part 1) as a prelude to a study (Part 2–4) of the various theories that have been advanced to explain retention of the base without mechanical support. These theories are critically reviewed and tabulated in chronological order. Some areas for further investigation are identified.  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