全文获取类型
收费全文 | 13816篇 |
免费 | 1232篇 |
国内免费 | 55篇 |
专业分类
耳鼻咽喉 | 37篇 |
儿科学 | 221篇 |
妇产科学 | 260篇 |
基础医学 | 392篇 |
口腔科学 | 1479篇 |
临床医学 | 2638篇 |
内科学 | 1181篇 |
皮肤病学 | 58篇 |
神经病学 | 997篇 |
特种医学 | 101篇 |
外科学 | 758篇 |
综合类 | 1701篇 |
预防医学 | 4061篇 |
眼科学 | 58篇 |
药学 | 843篇 |
7篇 | |
中国医学 | 50篇 |
肿瘤学 | 261篇 |
出版年
2024年 | 40篇 |
2023年 | 392篇 |
2022年 | 494篇 |
2021年 | 752篇 |
2020年 | 772篇 |
2019年 | 817篇 |
2018年 | 758篇 |
2017年 | 574篇 |
2016年 | 531篇 |
2015年 | 493篇 |
2014年 | 776篇 |
2013年 | 1368篇 |
2012年 | 763篇 |
2011年 | 809篇 |
2010年 | 585篇 |
2009年 | 576篇 |
2008年 | 634篇 |
2007年 | 644篇 |
2006年 | 536篇 |
2005年 | 398篇 |
2004年 | 338篇 |
2003年 | 309篇 |
2002年 | 265篇 |
2001年 | 226篇 |
2000年 | 210篇 |
1999年 | 161篇 |
1998年 | 150篇 |
1997年 | 130篇 |
1996年 | 119篇 |
1995年 | 76篇 |
1994年 | 55篇 |
1993年 | 39篇 |
1992年 | 37篇 |
1991年 | 34篇 |
1990年 | 39篇 |
1989年 | 19篇 |
1988年 | 23篇 |
1987年 | 19篇 |
1986年 | 8篇 |
1985年 | 32篇 |
1984年 | 34篇 |
1983年 | 18篇 |
1982年 | 11篇 |
1981年 | 9篇 |
1980年 | 14篇 |
1979年 | 4篇 |
1978年 | 2篇 |
1977年 | 4篇 |
1975年 | 2篇 |
1974年 | 3篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Objectives: To validate the accuracy of using probabilistic linkage for matching de‐identified ambulance records to a state trauma registry. Methods: This was a retrospective cohort analysis. Three thousand nine hundred nineteen true matches between ambulance and state trauma registry data from 1998 to 2003 were identified by deterministic matching on trauma identification number and verified by human review. Two thousand thirty‐eight ambulance records from trauma patients not meeting criteria for a true match, and an identical number of trauma registry records randomly selected from the one local county served by a different EMS provider, were included as nonmatches. There were 17 variables considered for linkage, which included the following: age, gender, race, county, hospital, date, rural setting, call and arrival times, mechanism, penetrating injury, vital signs, intubation, and intoxication. Probabilistic linkage was used to link the two data sets, using seven different combinations of common variables (maximum, 17; minimum, 4). The sensitivity and specificity of identifying true matches and nonmatches (95% confidence intervals [95% CI]) were calculated for each combination of variables. Results: Using all 17 available variables, 3,766 of 3,919 true matches were appropriately linked (sensitivity, 96.1%; 95% CI = 95.4% to 96.7%), with eight mismatches (specificity, 99.6%; 95% CI = 99.2% to 99.8%). Sensitivity fell below 95% with < 15 variables; however, sensitivity was very dependent on the inclusion of variables with high discriminatory power. Specificity remained >98% regardless of the number of variables included. Conclusions: Probabilistic linkage is a valid method for matching ambulance records to a trauma registry without the use of patient identifiers; however, the sensitivity of identifying true matches is critically dependent on the number and type of common variables included in the analysis. 相似文献
42.
P. E. Langdon A. Swift & R. Budd 《Journal of intellectual disability research : JIDR》2006,50(11):828-836
Background The social climate of inpatient facilities is thought to be an important contributor to treatment outcome. However, little research has focused on this construct within secure forensic services for people with intellectual disabilities (ID). Therefore, the objective of this study was to investigate the social climate of two different types of secure units (‘low’ secure vs. ‘medium’ secure) contained within the same facility for offenders with ID. Two hypotheses were generated: (1) residents would rate the social climate of the whole facility in a more negative direction than staff, and (2) residents and staff would rate the social climate of the ‘low’ secure unit in a more positive direction than that of the ‘medium’ secure unit. Method Using a 2 (factor ‘Participant’ = Staff or Resident) × 2 (factor ‘Unit’ = ‘Low’ or ‘Medium’ Secure Unit) between‐subjects design, 18 residents and 37 staff members were recruited and completed the Correctional Institutions Environment Scale (CIES), a measure of social climate. Results Residents tended to rate the units in a more positive direction than staff on some sub‐scales. Participants rated the ‘low’ secure unit in a more positive direction than the ‘medium’ secure unit on two sub‐scales of the CIES. However, on selected sub‐scales there were differences. The findings of this study suggest that the CIES may be a valid instrument for use within forensic services for people with ID, and further suggests that residents and staff have different perceptions of the shared social climate, which may have implications for service development. 相似文献
43.
44.
Alfred Sommer 《International ophthalmology》1994,18(5):287-292
Adapted from Keynote Addresses to the 5th General Assembly of the International Agency for the Prevention of Blindness, Berlin, Germany, May 9, 1994, and to the International Congress of Ophthalmology, Toronto, Canada, June 29, 1994. 相似文献
45.
Rashmi Kothari MD Kent Hall MD Thomas Brott MD Joseph Broderick MD 《Academic emergency medicine》1997,4(10):986-990
Objective : To develop an abbreviated and practical neurologic scale that could assist emergency medical services or triage personnel in identifying patients with stroke.
Methods : A prospective, observational, cohort study was performed at university-based EDs. Participants were 74 patients treated in a thrombolytic stroke trial and 225 consecutive non-stroke patients evaluated during 4 random 12-hour shifts in the ED. Scores on the NIH Stroke Scale were obtained for all patients by physicians. Items of this scale were modified and recoded to a binomial (normal or abnormal) scale. Serial univariate analyses using χ2 were performed to rank items. Recursive partitioning was then performed to develop the decision rule for predicting the presence of stroke.
Results : Three items identified 100% of patients with stroke: facial palsy, motor arm, and dysarthria. An Abbreviated NIH Stroke Scale based on these items had a sensitivity of 100% and a specificity of 92%. A proposed Out-of-hospital NIH Stroke Scale consisting of facial palsy, motor arm, and a combination of dysarthria and best language items (abnormal speech) had a sensitivity of 100% and a specificity of 88%.
Conclusion : Using the derivation data set, a proposed Out-of-hospital NIH Stroke Scale had a high sensitivity and specificity for identifying patients with stroke when performed by physicians in this group of 299 ED patients. Prospective studies of other health care professionals using the scale in the out-of-hospital arena are needed. 相似文献
Methods : A prospective, observational, cohort study was performed at university-based EDs. Participants were 74 patients treated in a thrombolytic stroke trial and 225 consecutive non-stroke patients evaluated during 4 random 12-hour shifts in the ED. Scores on the NIH Stroke Scale were obtained for all patients by physicians. Items of this scale were modified and recoded to a binomial (normal or abnormal) scale. Serial univariate analyses using χ
Results : Three items identified 100% of patients with stroke: facial palsy, motor arm, and dysarthria. An Abbreviated NIH Stroke Scale based on these items had a sensitivity of 100% and a specificity of 92%. A proposed Out-of-hospital NIH Stroke Scale consisting of facial palsy, motor arm, and a combination of dysarthria and best language items (abnormal speech) had a sensitivity of 100% and a specificity of 88%.
Conclusion : Using the derivation data set, a proposed Out-of-hospital NIH Stroke Scale had a high sensitivity and specificity for identifying patients with stroke when performed by physicians in this group of 299 ED patients. Prospective studies of other health care professionals using the scale in the out-of-hospital arena are needed. 相似文献
46.
This paper describes a teaching programme for final- (sixth-) year undergraduate medical students during their 10-week term in child health. Students attend schools on two occasions and are actively involved in the physical, educational and emotional assessment of children. The advantages of the programme include active participation by the students, contact with children in a less threatening environment, learning new skills in the assessment of children, and knowledge of common screening procedures. Student evaluation of the programme has been positive. 相似文献
47.
T. WlSBORG A. B. GUTTORMSEN M. B. SøRENSEN H. K. FLAATTEN 《Acta anaesthesiologica Scandinavica》1994,38(7):657-661
The use of anaesthesiologists in prehospital emergency care is controversial. We wanted to assess the impact of an anaesthesiologist and a short time interval from acceptance of a mission to take–off at survival rates in a rural/urban emergency medical service. Prospectively registered data for 991 consecutive patients through a 12–month period were retrospectively evaluated by an independent foreign expert. Of all primary missions, 3.3% were considered probably lifesaving from site of injury to receiving hospital. Of these, the lifesaving result in 50% were dependent on both the qualifications of the anaesthesiologist and a short response time. Survival from hospital admission to discharge was 44%. All patients were discharged to their own homes, able to live a fully functional life. The consistent use of anaesthesiologists compared to less qualified personnel and the maintaining of response times below presently required minima doubles the potential for lives saved in services comparable to the one studied. 相似文献
48.
49.
Eric M Cheng Andrew Siderowf Kari Swarztrauber Mahmood Eisa Martin Lee Barbara G Vickrey 《Movement disorders》2004,19(2):136-150
Parkinson's disease (PD) is a major cause of disability. To date, there have been no large-scale efforts to measure the quality of PD care because of a lack of quality indicators for conducting an explicit review of PD care processes. We present a set of quality indicators for PD care. Based on a structured review of the medical literature, 79 potential indicators were drafted. Through a two-round modified Delphi process, an expert panel of seven movement disorders specialists rated each indicator on criteria of validity, feasibility, impact on outcomes, room for improvement, and overall utility. Seventy-one quality indicators met validity and feasibility thresholds. Applying thresholds for impact on outcomes, room for improvement, and overall utility, a subset of 29 indicators was identified, spanning dopaminergic therapy, assessment of functional status, assessment and treatment of depression, coordination of care, and medication use. Multivariable analysis showed that overall utility ratings were driven by validity and impact on outcomes (P < 0.01). An expert panel can reach consensus on a set of highly rated quality indicators for PD care, which can be used to assess quality of PD care and guide the design of quality improvement projects. 相似文献
50.