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   1245篇
  免费   69篇
耳鼻咽喉   65篇
儿科学   17篇
妇产科学   21篇
基础医学   169篇
口腔科学   116篇
临床医学   75篇
内科学   241篇
皮肤病学   13篇
神经病学   117篇
特种医学   65篇
外科学   140篇
综合类   28篇
预防医学   90篇
眼科学   21篇
药学   79篇
中国医学   2篇
肿瘤学   55篇
  2022年   9篇
  2021年   19篇
  2020年   9篇
  2019年   9篇
  2018年   29篇
  2017年   11篇
  2016年   21篇
  2015年   27篇
  2014年   31篇
  2013年   55篇
  2012年   68篇
  2011年   51篇
  2010年   34篇
  2009年   33篇
  2008年   53篇
  2007年   72篇
  2006年   50篇
  2005年   67篇
  2004年   48篇
  2003年   30篇
  2002年   35篇
  2001年   45篇
  2000年   44篇
  1999年   24篇
  1998年   14篇
  1996年   8篇
  1994年   10篇
  1993年   7篇
  1992年   36篇
  1991年   34篇
  1990年   23篇
  1989年   29篇
  1988年   27篇
  1987年   19篇
  1986年   17篇
  1985年   13篇
  1984年   10篇
  1983年   7篇
  1982年   8篇
  1979年   9篇
  1978年   14篇
  1977年   10篇
  1974年   6篇
  1973年   8篇
  1971年   6篇
  1969年   8篇
  1968年   7篇
  1967年   9篇
  1966年   10篇
  1965年   9篇
排序方式: 共有1314条查询结果,搜索用时 0 毫秒
51.
OBJECTIVE: To review the literature of the validity of the Hospital Anxiety and Depression Scale (HADS). METHOD: A review of the 747 identified papers that used HADS was performed to address the following questions: (I) How are the factor structure, discriminant validity and the internal consistency of HADS? (II) How does HADS perform as a case finder for anxiety disorders and depression? (III) How does HADS agree with other self-rating instruments used to rate anxiety and depression? RESULTS: Most factor analyses demonstrated a two-factor solution in good accordance with the HADS subscales for Anxiety (HADS-A) and Depression (HADS-D), respectively. The correlations between the two subscales varied from.40 to.74 (mean.56). Cronbach's alpha for HADS-A varied from.68 to.93 (mean.83) and for HADS-D from.67 to.90 (mean.82). In most studies an optimal balance between sensitivity and specificity was achieved when caseness was defined by a score of 8 or above on both HADS-A and HADS-D. The sensitivity and specificity for both HADS-A and HADS-D of approximately 0.80 were very similar to the sensitivity and specificity achieved by the General Health Questionnaire (GHQ). Correlations between HADS and other commonly used questionnaires were in the range.49 to.83. CONCLUSIONS: HADS was found to perform well in assessing the symptom severity and caseness of anxiety disorders and depression in both somatic, psychiatric and primary care patients and in the general population.  相似文献   
52.
Recent identification of ion channel gene mutations in Mendelian epilepsies suggests that genetically driven neuronal hyperexcitability plays an important role in epileptogenesis. In this study, we tested the hypothesis that genetic variation in the human SCN2B gene confers liability to common subtypes of idiopathic generalized epilepsies (IGE). A systematic search for mutations was performed in 92 IGE patients. We detected a novel single nucleotide polymorphism (SNP), however, allele frequencies did not differ between IGE patients and controls (chi2 = 0.19, df = 1, p = 0.744). Furthermore, a missense mutation in codon 209 (Asn209Pro) was identified in one patient, but was found to be absent in an affected sibling of the index patient. Thus, our results do not suggest a major role of the SCN2B gene in the etiology of common IGE subtypes.  相似文献   
53.
Functional results after laparoscopic rectopexy for rectal prolapse   总被引:3,自引:0,他引:3  
We investigated the functional results after laparoscopic rectopexy for rectal prolapse in 29 patients at least 12 months postoperatively. Twenty patients were evaluated completely pre- and postoperatively (median 22 months postoperatively, range 12 to 54 months). Six patients were interviewed by telephone, two patients were lost to follow-up, and one patient died of causes unrelated to rectal prolapse. Patients underwent a proctologic examination, anoscopy, rigid sigmoidoscopy, fluoroscopic defecography, and anorectal manometry pre- and postoperatively, and an additional standardized interview postoperatively. Anorectal manometry showed a significant increase in maximum anal resting and squeeze pressures postoperatively (resting pressure 72 ±8 vs. 95 ±13 mm Hg, pre- vs. postoperatively; P = 0.046; squeeze pressure 105 ±17 vs. 142 ±19 mm Hg, pre- vs. postoperatively; P = 0.035), and continence improved postoperatively (Wexner incontinence score 6.0 ±1.0 vs. 3.9 ± 0.8 pre- vs. postoperatively, P = 0.02). Twenty (77%) of 26 patients were satisfied with the operative result, but functional morbidity was observed in four patients, with two patients complaining of severe evacuation problems. Rectal prolapse recurred in one patient 42 months postoperatively (recurrence rate 1 [3.8%] of 26 patients). Functional results were very similar to those obtained after open rectopexy, with symptoms of prolapse and incontinence improved in the great majority of patients. Presented at the Fortieth Annual Meeting of The Society for Surgery of the Alimentary Tract, Orlando, Fla., May 16–19, 1999.  相似文献   
54.
OBJECTIVE: Various materials have been used as human bone substitutes in rigid fixation research. We hypothesize that these substitutes behave differently than human cadaveric bone in maxillofacial research. STUDY DESIGN: Screw insertion torque and pull-out strength of titanium maxillofacial self-tapping bone screws (1.0 mm and 2.4 mm outer diameter) were measured in cadaveric mandible and in the following materials: bovine rib, porcine rib, photoelastic epoxy, red oak, and 2 types of synthetic mandibles. Results were tested for statistically significant differences (unpaired t test, P <.05) in comparison with human bone. RESULTS: For 1.0-mm screws, statistically significant differences were found for the synthetic mandibles groups and oak groups for insertion torque and porcine rib for pull-out strength. For 2.4-mm screws, statistically significant differences were found for the porcine rib and oak groups for insertion torque and the bovine rib and epoxy groups for pull-out strength. CONCLUSION: The results suggest that human bone can be simulated in fixation studies with bone substitute materials.  相似文献   
55.
Approximately 22 million children are injured in the United States annually. Children are uniquely susceptible to craniofacial trauma because of their greater cranial-mass-to-body ratio. The pediatric population sustains 1% to 14.7% of all facial fractures. The majority of these injuries are encountered by boys (53.7% - 80%) who are involved in motor vehicle accidents (up to 80.2%). The incidence of other systemic injury concomitant to facial trauma is significant (10.4% - 88%). The management of the pediatric patient with maxillofacial injury should take into consideration the differences in anatomy and physiology between children and adults, the presence of concomitant injury, the particular stage in growth and development (anatomic, physiologic, and psychologic), and the specific injuries and anatomic sites that the injuries affect. This comprehensive review, based on the last 25 years of the world's English-speaking surgical literature, presents current thoughts on the anatomic and physiologic differences between adults and children, a synopsis of childhood growth and development, and an overview of state-of-the-art management of the pediatric patient who has sustained maxillofacial injury.  相似文献   
56.
R J Sanders  C E Haug  W H Pearce 《Journal of vascular surgery》1990,12(4):390-8; discussion 398-400
Recurrent symptoms develop in 15% to 20% of patients undergoing either first rib resection or scalenectomy for thoracic outlet syndrome. Over the past 22 years 134 operations for recurrence were performed in 97 patients. Four operations were used: transaxillary first rib resection (26); supraclavicular first rib resection with neurolysis (15); scalenectomy with neurolysis (58); and brachial plexus neurolysis (35). Complications included temporary plexus injury (0.7%), temporary phrenic palsy (3.7%), and permanent phrenic palsy (1.4%). The combined primary success rate of all four operations for recurrence was 84% in the first 3 months. This fell to 59% at 1 to 2 years; 50% at 3 to 5 years; and 41% at 10 to 15 years. No significant difference was found in results between the four operations used for recurrence. When recurrence was caused by trauma the results of reoperations were better than when recurrence was spontaneous. The primary success rates of three initial operations for thoracic outlet syndrome were compared to their secondary success rates (improved after reoperation). By use of life-table methods, reoperation improved the 5- to 10-year success rate of transaxillary first rib resection from 69% to 86% and for scalenectomy from 69% to 84%. Reoperation is successful in most cases of recurrent thoracic outlet syndrome and better when recurrence is the result of a neck injury.  相似文献   
57.
Zusammenfassung An 31 ohrgesunden Meerschweinchen wurde Tetracyclin in gelöster Form in das Mittelohr appliziert. Dabei wurden entweder nur die beiden Fensternischen oder die gesamte Paukenhöhle gefüllt. Die gefrorenen Köpfe wurden im Kryotom geschnitten und im UV-Licht betrachtet. Auf diese Weise konnte das Tetracyclin im Innenohr nachgewiesen werden. Durch das Einfrieren des Kopfes wurden die Flüssigkeitsräume von Innenohr und Gehirn weder bei der Applikation noch bei der Auswertung eröffnet.Das Tetracyclin gelangt vor allem über das runde Fenster ins Innenohr. Außerdem kann es auch über das ovale Fenster in das Vestibulum eindringen. Als weitere Zugangswege kommen die Diffusion durch die knöcherne Labyrinthkapsel sowie der Transport über labyrinthdurchquerende Gefäße in Betracht. Von der ersten Windung der Scala tympani gelangt das Tetracyclin relativ schnell über den Aquaeductus cochleae in den Subarachnoidalraum.Auszugsweise Veröffentlichung der Dissertation von Hans-Peter Haug  相似文献   
58.
59.
60.
OBJECTIVE: To study the prevalence of vitamin D deficiency and to identify possible predictors of vitamin D deficiency in five main immigrant groups in Oslo. DESIGN: Cross-sectional, population-based. SETTING: City of Oslo. SUBJECTS: In total, 491 men and 509 women with native countries Turkey, Sri Lanka, Iran, Pakistan and Vietnam living in the county of Oslo. RESULTS: Median serum 25(OH)D level (s-25(OH)D) was 28 nmol/l, ranging from 21 nmol/l in women born in Pakistan to 40 nmol/l in men born in Vietnam. Overall prevalence of vitamin D deficiency defined as s-25(OH)D<25 nmol/l was 37.2%, ranging from 8.5% in men born in Vietnam to 64.9% in women born in Pakistan. s-25(OH)D did not vary significantly with age. s-25(OH)D was higher in blood samples drawn in June compared to samples obtained in April, but not significantly for women. Reported use of fatty fish and cod liver oil supplements showed a strong positive association with s-25(OH)D in all groups. Education length was positively associated with s-25(OH)D in women, whereas body mass index (BMI) was inversely associated with s-25(OH)D in women. These two variables were not related to vitamin D deficiency in men. CONCLUSIONS: There is widespread vitamin D deficiency in both men and women born in Turkey, Sri Lanka, Iran, Pakistan and Vietnam residing in Oslo. The prevalence of vitamin D deficiency is higher in women than in men, and it is higher in those born in Pakistan and lower in those born in Vietnam compared to the other ethnic groups. Fatty fish intake and cod liver oil supplements are important determinant factors of vitamin D status in the groups studied. BMI and education length are also important predictors in women.  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