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   5390篇
  免费   370篇
  国内免费   14篇
耳鼻咽喉   78篇
儿科学   207篇
妇产科学   104篇
基础医学   704篇
口腔科学   89篇
临床医学   484篇
内科学   1320篇
皮肤病学   344篇
神经病学   375篇
特种医学   163篇
外科学   734篇
综合类   39篇
一般理论   7篇
预防医学   385篇
眼科学   64篇
药学   320篇
中国医学   2篇
肿瘤学   355篇
  2023年   53篇
  2022年   74篇
  2021年   126篇
  2020年   104篇
  2019年   153篇
  2018年   147篇
  2017年   124篇
  2016年   147篇
  2015年   125篇
  2014年   203篇
  2013年   281篇
  2012年   341篇
  2011年   357篇
  2010年   186篇
  2009年   202篇
  2008年   358篇
  2007年   319篇
  2006年   334篇
  2005年   297篇
  2004年   260篇
  2003年   265篇
  2002年   249篇
  2001年   65篇
  2000年   42篇
  1999年   64篇
  1998年   52篇
  1997年   38篇
  1996年   36篇
  1995年   47篇
  1994年   32篇
  1993年   24篇
  1992年   28篇
  1991年   29篇
  1990年   29篇
  1989年   24篇
  1988年   22篇
  1987年   16篇
  1986年   31篇
  1985年   16篇
  1984年   24篇
  1983年   26篇
  1982年   15篇
  1981年   20篇
  1980年   17篇
  1979年   13篇
  1973年   14篇
  1972年   13篇
  1971年   11篇
  1970年   14篇
  1967年   19篇
排序方式: 共有5774条查询结果,搜索用时 15 毫秒
991.
BackgroundBreast conservation treatment (BCT), consisting of breast conservation surgery followed by definitive radiation therapy (RT), has been shown to be effective for early-stage breast cancer. Patterns of metastatic failure by specific anatomic site are not well described in the literature.MethodsA total of 1754 patients with stage I or II invasive carcinoma of the breast treated with BCT between 1977 and 2003 were identified. Patients were scored based on first site of metastasis: bone, brain, lung, liver, or other. Non–breast cancer deaths, contralateral breast cancer, and second malignancies were treated as competing risks events. Cumulative incidence functions for each competing event were calculated using competing risk methodology. Univariate analysis was performed to determine the hazard ratio (HR) associated with patient and tumor characteristics.ResultsThe most common event was non–breast cancer death (16.5% at 15 years; 95% confidence interval [CI], 13.9%-19.4%). The most common exclusive first site of metastasis was bone (5.9% at 15 years). The 4 most common anatomic sites of distant metastases as the first exclusive event were bone (41.1%), lung (22.4%), liver (7.3%), and brain (7.3%).ConclusionThe present study has demonstrated the site-specific risks of metastases. These data support current clinical practice of screening for site-specific metastatic disease after BCT based on concerning patient-specific signs or symptoms.  相似文献   
992.
The aims of the study were to describe the level of dental anxiety in a representative sample of an adult population, to evaluate different demographic variables in relation to dental anxiety, and to compare two measurement scales of dental anxiety. A random sample of residents (n = 830) of the city of Gothenburg (population 432,000) was selected for a telephone survey. The survey comprised different questions concerning demographic variables, dental care habits, and the level of dental anxiety. The methods of measurement of dental anxiety were a 10-point dental Fear Scale (FS) and the Corah Dental Anxiety Scale (DAS). A total of 620 interviews were completed giving a response rate of 74.7%. 41.4% of the respondents were males, 58.6% females. Females were significantly more likely to report a high dental anxiety compared with males. The prevalence of high dental anxiety in the sample as measured by the FS and DAS was 6.7% and 5.4% respectively. The correlation between the FS and DAS was 0.81. The distribution of high dental anxiety and age showed a clearly and significantly higher portion of dental anxiety in the age group 20-39 yr compared to both younger and older groups. The effect of dental anxiety on regularity of dental visits revealed a significant difference as measured by the FS. No significant correlation was found between dental anxiety and educational level or income. A majority of the respondents (82-95%) expressed a desire for establishment of a special dental fear treatment clinic without need for referral.  相似文献   
993.
OBJECTIVE: To record maxillary and mandibular displacement with articular growth and in response to bimaxillary surgical repositioning in patients with hemifacial microsomia (HFM) and to observe ipsilateral corpus/ramus growth in severely affected children. DESIGN: Prospective roentgen stereometric analysis (mean age 7 years 10 months to 18 years 0 months) and retrospective profile and panoramic roentgenograms. Mean total observation period was 9 years 1 month. SETTING: Department of Plastic and Reconstructive Surgery, Malm? University Hospital (Malm?, Sweden). PATIENTS: Twenty-one patients consecutively diagnosed from 1976 through 1988 with HMF, five of whom had bimaxillary surgery. INTERVENTIONS: Surgery was performed at the Department of Plastic and Reconstructive Surgery. Implants were inserted at the initial reconstructive surgical procedure under general anesthesia. Roentgen examinations were performed in connection with continued clinical evaluations and treatment. MAIN OUTCOME MEASURES: Stereo roentgenograms were digitized at the Department of Orthopedic Surgery, Malm? University Hospital (Malm?, Sweden). RESULTS: Displacement of the jaws with articular growth and in response to bimaxillary surgical repositioning varied interindividually with no apparent common pattern. Relapse displacement occurred several years after bimaxillary surgery. Mandibular growth changes were found in the corpus/ramus area and alveolar process on the affected side. CONCLUSIONS: A marked interindividual variability of maxillary and mandibular displacement indicates that the relevance of statistical analysis of HFM growth data may be questioned. We would suggest that precise and accurate longitudinal recordings of growth and response to surgery in individual HFM patients be more appropriate.  相似文献   
994.
995.
When gold sodium thiosulfate was added to the patch test standard series, positive reactions were obtained in 8.6% of 823 consecutive patients with suspect contact allergy. The test reactions were clinically of an allergic type and, in several cases, long-lasting. There was no correlation with other allergens in the standard series. In a special study on 38 patients with contact allergy to gold sodium thiosulfate, the following principal findings were obtained: positive patch tests to the compound itself in dilute concentration; positive patch tests to potassium dicyanoaurate; negative patch tests to gold sodium thiomalate, sodium thiosulfate, and metallic gold; positive intradermal tests to gold sodium thiomalate. Our findings make gold sodium thiosulfate the 2nd most common contact allergen after nickel sulfate. It is suggested that a positive skin test to gold sodium thiosulfate represents gold allergy.  相似文献   
996.
11 cases of contact dermatitis from Vulkan heat retainers are reported. The skin eruptions started on days 1-11 after the 1st day of exposure. The clinical picture varied from eczema through urticaria to purpura. In some cases, the symptoms were severe. Patch testing was performed in 10 individuals and all reacted positively to the heat retainer and/or the rubber glue used in the heat retainer. A series of rubber chemicals was patch tested in 7 patients and all showed positive reactions to diphenylthiourea (DPTU), and all but one to ethylene thiourea (ETU). TLC examination revealed a spot with the same RF-value as DPTU in extracts of the adhesive, but no spot corresponding to ETU. There were no indications of impurities in the test preparations of DPTU and ETU. By HPLC, the content of DPTU in the adhesive was determined as 0.6% w/w.  相似文献   
997.
998.
The preservative Kathon CG has become one of the most common sensitizers. It has, however, been difficult to explain the sensitization and to assess the clinical relevance of the contact allergy, partly due to lack of specification of the preservative in products. A high-performance liquid chromatography method was used to demonstrate Kathon CG in 123 commercial products of both "leave on" and "rinse off" types. 38 of these contained Kathon CG in the range of 1-15 ppm of active ingredients. There were no differences between "leave on" and "rinse off" products concerning the relative number of products containing Kathon CG and the concentrations of the preservative.  相似文献   
999.
Aim: To study the connection between reaction to soy milk and IgE sensitization to Gly m 4. Methods: Four subjects who experienced unforeseen and severe symptoms after the ingestion of soymilk were studied. Results: All children were birch pollen allergic, had high IgE responses to the PR‐10 proteins from birch and soybean, Bet v 1 and Gly m 4. All reactions took place after the ingestion of soymilk during the peak pollen season. Conclusion: This is the first time soybean‐dependant pollen‐food cross‐reaction has been reported in children experiencing reactions during the birch pollen season. These findings may well be helpful to doctors in identifying individuals at risk of severe reactions upon the ingestion of soymilk, and we foresee an increase in the number of similar cases as soy drinks are promoted for health purposes.  相似文献   
1000.
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