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   16765篇
  免费   1191篇
  国内免费   32篇
耳鼻咽喉   118篇
儿科学   650篇
妇产科学   486篇
基础医学   2100篇
口腔科学   247篇
临床医学   2688篇
内科学   2889篇
皮肤病学   165篇
神经病学   1407篇
特种医学   272篇
外国民族医学   1篇
外科学   1284篇
综合类   578篇
一般理论   37篇
预防医学   2577篇
眼科学   311篇
药学   909篇
中国医学   8篇
肿瘤学   1261篇
  2023年   85篇
  2022年   132篇
  2021年   314篇
  2020年   208篇
  2019年   308篇
  2018年   325篇
  2017年   245篇
  2016年   315篇
  2015年   386篇
  2014年   486篇
  2013年   810篇
  2012年   1179篇
  2011年   1242篇
  2010年   581篇
  2009年   555篇
  2008年   1062篇
  2007年   1201篇
  2006年   1153篇
  2005年   1144篇
  2004年   1153篇
  2003年   1081篇
  2002年   1030篇
  2001年   144篇
  2000年   113篇
  1999年   156篇
  1998年   210篇
  1997年   196篇
  1996年   186篇
  1995年   180篇
  1994年   144篇
  1993年   125篇
  1992年   93篇
  1991年   81篇
  1990年   97篇
  1989年   93篇
  1988年   92篇
  1987年   59篇
  1986年   68篇
  1985年   67篇
  1984年   75篇
  1983年   76篇
  1982年   72篇
  1981年   87篇
  1980年   77篇
  1979年   65篇
  1978年   53篇
  1977年   51篇
  1976年   48篇
  1975年   28篇
  1974年   42篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
ABSTRACT

This work collates data from the analysis of complex mixtures analysed in STRmix during routine no-suspect volume crime work. It interrogates the upload rate for these types of mixtures and which component of the profile has been able to be interpreted for upload. The number of profiles giving multiple uploads and the amount of replicate PCR analysis has been collated.  相似文献   
2.
166Ho-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylene-phosphonate (DOTMP) is a tetraphosphonate molecule radiolabeled with 166Ho that localizes to bone surfaces. This study evaluated pharmacokinetics and radiation-absorbed dose to all organs from this beta-emitting radiopharmaceutical. METHODS: After two 1.1-GBq administrations of 166Ho-DOTMP, data from whole-body counting using a gamma-camera or uptake probe were assessed for reproducibility of whole-body retention in 12 patients with multiple myeloma. The radiation-absorbed dose to normal organs was estimated using MIRD methodology, applying residence times and S values for 166Ho. Marrow dose was estimated from measured activity retained after 18 h. The activity to deliver a therapeutic dose of 25 Gy to the marrow was determined. Methods based on region-of-interest (ROI) and whole-body clearance were evaluated to estimate kidney activity, because the radiotracer is rapidly excreted in the urine. The dose to the surface of the bladder wall was estimated using a dynamic bladder model. RESULTS: In clinical practice, gamma-camera methods were more reliable than uptake probe-based methods for whole-body counting. The intrapatient variability of dose calculations was less than 10% between the 2 tracer studies. Skeletal uptake of 166Ho-DOTMP varied from 19% to 39% (mean, 28%). The activity of 166Ho prescribed for therapy ranged from 38 to 67 GBq (1,030-1,810 mCi). After high-dose therapy, the estimates of absorbed dose to the kidney varied from 1.6 to 4 Gy using the whole-body clearance-based method and from 8.3 to 17.3 Gy using the ROI-based method. Bladder dose ranged from 10 to 20 Gy, bone surface dose ranged from 39 to 57 Gy, and doses to other organs were less than 2 Gy for all patients. Repetitive administration had no impact on tracer biodistribution, pharmacokinetics, or organ dose. CONCLUSION: Pharmacokinetics analysis validated gamma-camera whole-body counting of 166Ho as an appropriate approach to assess clearance and to estimate radiation-absorbed dose to normal organs except the kidneys. Quantitative gamma-camera imaging is difficult and requires scatter subtraction because of the multiple energy emissions of 166Ho. Kidney dose estimates were approximately 5-fold higher when the ROI-based method was used rather than the clearance-based model, and neither appeared reliable. In future clinical trials with 166Ho-DOTMP, we recommend that dose estimation based on the methods described here be used for all organs except the kidneys. Assumptions for the kidney dose require further evaluation.  相似文献   
3.
4.
PURPOSE: To provide a model for assessing occupational therapy workforce needs by using a demand-based approach to determine current workforce status in the Northwest region. Regional information may have implications for addressing national occupational therapy service needs. METHOD: A questionnaire was sent to a proportional random sample of 234 facilities that hire occupational therapy practitioners. Data were collected in July-August 2003 using structured mailing and follow-up procedures. RESULTS: Response rate was 79%. Twenty-four percent reported occupational therapy vacancies and 11% occupational therapy assistant vacancies; 48% predicted an increase in occupational therapy positions in the next 2 years and 41% an increase in occupational therapy assistant positions. Sixty-three percent of respondents reported difficulty in hiring. DISCUSSION: This study identifies an occupational therapy workforce shortage in the Northwest. Management of a shortage is critical, for even short-term adjustments could lead to permanent changes in service provision. This study demonstrates the importance of current information on the status of the national workforce and serves as a model for future studies.  相似文献   
5.
我们现在要尽量使这些治疗方法进入临床试验证明他们的可行性现在脊髓损伤的临床试验基金很有限,所以只有很少的这些治疗方法真正用于病人主要的制药厂开始对脊髓损伤治疗产生兴趣,我们现在还有很多工作要做,但是前景方向十分清楚,我们需要努力快速的工作。  相似文献   
6.
J Treasure 《The Practitioner》1989,233(1479):1525-1527
Anorexia and bulimia nervosa are aetiologically distinct diseases with different treatments. Though it was described more recently, bulimia nervosa occurs more commonly. Accurate diagnosis and early treatment should reduce the mortality of both conditions.  相似文献   
7.
8.
PURPOSE: Epidermal growth factor receptor is expressed in pediatric malignant solid tumors. We conducted a phase I trial of gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor, in children with refractory solid tumors. PATIENTS AND METHODS: Gefitinib (150, 300, 400, or 500 mg/m2) was administered orally to cohorts of three to six patients once daily continuously until disease progression or significant toxicity. Pharmacokinetic studies were performed during course one (day 1 through 28). RESULTS: Of the 25 enrolled patients, 19 (median age, 15 years) were fully evaluable for toxicity and received 54 courses. Dose-limiting toxicity was rash in two patients treated with 500 mg/m2 and elevated ALT and AST in one patient treated with 400 mg/m2. The maximum-tolerated dose was 400 mg/m2/d. The most frequent non-dose-limiting toxicities were grade 1 or 2 dry skin, anemia, diarrhea, nausea, and vomiting. One patient with Ewing's sarcoma had a partial response. Disease stabilized for 8 to > or = 60 weeks in two patients with Wilms' tumor and two with brainstem glioma (one exophytic). At 400 mg/m2, the median peak gefitinib plasma concentration was 2.2 microg/mL (range, 1.2 to 3.6 microg/mL) and occurred at a median of 2.3 hours (range, 2.0 to 8.3 hours) after drug administration. The median apparent clearance and median half-life were 14.8 L/h/m2 (range, 3.8 to 24.8 L/h/m2) and 11.7 hours (range, 5.6 to 22.8 hours), respectively. Gefitinib systemic exposures were comparable with those associated with antitumor activity in adults. CONCLUSION: Oral gefitinib is well tolerated in children. Development of the drug in combination with cytotoxic chemotherapy will be pursued.  相似文献   
9.

Background  

Health service policy in the United Kingdom emphasises the importance of self-care by patients with chronic conditions. Written information for patients about their condition is seen as an important aid to help patients look after themselves. From a discourse analysis perspective written texts such as patient information leaflets do not simply describe the reality of a medical condition and its management but by drawing on some sorts of knowledge and evidence rather than others help construct the reality of that condition. This study explored patient information leaflets on osteoarthritis (OA) to see how OA was constructed and to consider the implications for self-care.  相似文献   
10.
Objectives: Heavy smokers are a segment of the smoking population who are at increased risk of smoking-related morbidity and least likely to achieve cessation. This study identifies the impact of heavy smoking on quality of life by gender and describes the subpopulation for improved targeting.Methods: South Australian representative population data (n = 3010) was used to compare the health-related quality of life status of male and female heavy smokers as assessed by the SF-36.  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