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   11752篇
  免费   732篇
  国内免费   16篇
耳鼻咽喉   54篇
儿科学   443篇
妇产科学   322篇
基础医学   1479篇
口腔科学   74篇
临床医学   2144篇
内科学   1968篇
皮肤病学   109篇
神经病学   1001篇
特种医学   242篇
外科学   1024篇
综合类   134篇
一般理论   8篇
预防医学   1736篇
眼科学   91篇
药学   688篇
中国医学   7篇
肿瘤学   976篇
  2023年   59篇
  2022年   106篇
  2021年   183篇
  2020年   118篇
  2019年   186篇
  2018年   241篇
  2017年   220篇
  2016年   188篇
  2015年   219篇
  2014年   365篇
  2013年   567篇
  2012年   815篇
  2011年   892篇
  2010年   498篇
  2009年   451篇
  2008年   775篇
  2007年   871篇
  2006年   840篇
  2005年   910篇
  2004年   910篇
  2003年   842篇
  2002年   769篇
  2001年   88篇
  2000年   64篇
  1999年   103篇
  1998年   144篇
  1997年   126篇
  1996年   98篇
  1995年   80篇
  1994年   79篇
  1993年   92篇
  1992年   54篇
  1991年   52篇
  1990年   46篇
  1989年   25篇
  1988年   37篇
  1987年   23篇
  1986年   27篇
  1985年   30篇
  1984年   45篇
  1983年   33篇
  1982年   44篇
  1981年   36篇
  1980年   32篇
  1979年   20篇
  1978年   12篇
  1977年   17篇
  1974年   9篇
  1973年   8篇
  1972年   9篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
41.
Extreme bradycardia during sleep apnea caused by myxedema   总被引:1,自引:0,他引:1  
A 52-year-old man with myxedema was evaluated for anterior chest pain that was considered to be compatible with myocardial ischemia. The night after admission he developed extreme bradycardia, hypotension, and apneic episodes lasting up to 25 s. Continuous positive airway pressure and administration of medroxyprogesterone acetate prevented further episodes and relieved much of the somnolence and lethargy that had contributed to the evidence for myxedema. Alveolar hypoventilation caused by decreased sensitivity to carbon dioxide, inadequate central neural drive, peripheral muscle force, and obesity all may have contributed to the apnea. Chest pain has not recurred, and results of electrocardiography have remained normal following full thyroid hormone replacement. The early recognition of myxedema causing sleep apnea will allow specific treatment to avoid the cardiovascular risks related to prolonged apnea and will help avoid confusion with other etiologies of cardiovascular abnormalities.  相似文献   
42.
43.
Alternative treatments such as troleandomycin methotrexate, gold, and intravenous gamma globulin are sometimes considered for severe asthmatics to minimize the need for systemic corticosteroids and reduce adverse effects. These alternative therapies may also be associated with significant toxicity and expense. The ability to reduce corticosteroid use and the need for alternative treatment interventions in 125 pediatric patients at our institution were reviewed. Because corticosteroid requirements were reduced significantly, only 23 of 125 children evaluated were considered for treatment alternatives with only 10 receiving such therapy. This study emphasizes the importance of a thorough and comprehensive review of corticosteroid requirements and usage prior to initiating alternative approaches to treatment in moderate to severe asthmatics as well as in patients thought to be “steroid-dependent.”  相似文献   
44.
BACKGROUND: Quality of life has increased in popularity as an outcome measure in health research. However, the measurement of quality of life has been questioned on methodologic grounds, as it often shows little association with objective measures of disease status. OBJECTIVE: For this report we studied the determinants of pediatric asthma caregiver report of quality of life and its relationship to disease burden. METHOD: Ninety-eight children who were admitted to a Pediatric Day Program for an asthma evaluation were enrolled in an outcome study. A complete set of medical records for the 2-year period before and after the admission was collected and systematically coded for health care utilization. Using the Pediatric Asthma Caregiver's Quality of Life Questionnaire, data were collected at baseline, discharge, and year after the admission. Caregiver negative affect (anxiety and depression), measured with the Brief Symptom Inventory, was also collected at baseline and discharge. RESULTS: Caregiver report of quality of life was unrelated to health care utilization at baseline but instead was significantly related to baseline caregiver negative affect. A significant relationship between health care utilization and quality of life was present at followup. The Emotional Function scale from the quality of life measure can account for most of the relationship between quality of life and negative affect. CONCLUSIONS: Caregiver affect may have a considerable influence on report of quality of life. Understanding the individual characteristics of the respondent is important when using a quality of life instrument as an outcome measure.  相似文献   
45.
46.
47.
HLA-A, -B, -C, -DR, and -DQ typings of the Schmiedeleut Hutterites of South Dakota were collected as part of an ongoing genetic-epidemiologic study of HLA and fertility. A total of 1,082 individuals, including 852 married adults representative of the reproductive population of this isolate, were characterized for five-locus HLA haplotypes. HLA-A1, A2, A3, and A24 accounted for 75% of observed HLA-A alleles and HLA-B27, B35, B51, and B62 accounted for 55% of observed HLA-B alleles. S-leut Hutterites are derived from 68 or fewer ancestors. However, only 48 ancestral HLA haplotypes were observed and nine of these accounted for over 52% of the observed haplotypes. Measures of two-locus linkage disequilibrium derived from these haplotypes indicated that one-third to half of the observed HLA-A/B, B/DR, and A/DR allele combinations exhibited highly statistically significant linkage disequilibrium. Allele and haplotype frequencies did not differ between males and females. Recombination rates of 0.004% and 0.005% between HLA-A and -C and between HLA-B and -DR, respectively, were observed. This HLA profile points out a paucity of HLA alleles and haplotypes in this population and marked linkage disequilibrium among the HLA alleles that are present. © Wiley-Liss, Inc.  相似文献   
48.
The purpose of this article is to describe the extent to which certified nurse-midwives (CNMs) provide care to vulnerable populations in the United States and the source of reimbursement for this care. The data were obtained from the first phase of a national study to address the characteristics of women served and cost of care provided by CNMs. Results were analyzed nationally and by American College of Nurse-Midwives regions. Certified nurse-midwives in all types of practices are providing care to women from populations that are vulnerable to poorer than average outcomes of childbirth because of age, socioeconomic status, refugee status, and ethnicity. Ninety-nine percent of CNMs report serving at least one group of vulnerable women, and CNMs in the inner city and rural practices serve several groups. The vast majority of CNMs are salaried; only 11% receive their primary income from fee-for-service. Fifty percent of the payment for CNM services is from Medicaid and government-subsidized sources whereas less than 20% comes from private insurance. Source of income varies by type of setting in which the CNM attends births. The results suggest that CNMs, as a group, make a major contribution to the care of vulnerable populations.  相似文献   
49.
Transient postictal hemiparesis or monoparesis is not uncommon after partial (focal) seizures. We report 2 patients who complained of severe bilateral limb weakness after generalized tonic-clonic seizures (GTCS) beginning focally. Bilateral Todd's paralysis was verified and documented in both patients. EEG and clinical evidence indicate the supplementary motor cortex as the most likely source of the seizures in both cases.  相似文献   
50.
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