全文获取类型
| 收费全文 | 3143028篇 |
| 免费 | 220714篇 |
| 国内免费 | 5119篇 |
专业分类
| 耳鼻咽喉 | 45716篇 |
| 儿科学 | 98219篇 |
| 妇产科学 | 82879篇 |
| 基础医学 | 439553篇 |
| 口腔科学 | 89898篇 |
| 临床医学 | 283030篇 |
| 内科学 | 604107篇 |
| 皮肤病学 | 65786篇 |
| 神经病学 | 256024篇 |
| 特种医学 | 124279篇 |
| 外国民族医学 | 1082篇 |
| 外科学 | 472643篇 |
| 综合类 | 72057篇 |
| 现状与发展 | 2篇 |
| 一般理论 | 1195篇 |
| 预防医学 | 244172篇 |
| 眼科学 | 74030篇 |
| 药学 | 238163篇 |
| 77篇 | |
| 中国医学 | 6381篇 |
| 肿瘤学 | 169568篇 |
出版年
| 2018年 | 31916篇 |
| 2017年 | 24746篇 |
| 2016年 | 27483篇 |
| 2015年 | 30778篇 |
| 2014年 | 43896篇 |
| 2013年 | 66141篇 |
| 2012年 | 89623篇 |
| 2011年 | 94693篇 |
| 2010年 | 55919篇 |
| 2009年 | 53201篇 |
| 2008年 | 89270篇 |
| 2007年 | 95437篇 |
| 2006年 | 96670篇 |
| 2005年 | 93518篇 |
| 2004年 | 90088篇 |
| 2003年 | 86885篇 |
| 2002年 | 85447篇 |
| 2001年 | 149132篇 |
| 2000年 | 154462篇 |
| 1999年 | 130332篇 |
| 1998年 | 36432篇 |
| 1997年 | 32816篇 |
| 1996年 | 32595篇 |
| 1995年 | 31252篇 |
| 1994年 | 29215篇 |
| 1993年 | 27310篇 |
| 1992年 | 104003篇 |
| 1991年 | 100294篇 |
| 1990年 | 97184篇 |
| 1989年 | 93857篇 |
| 1988年 | 86827篇 |
| 1987年 | 85159篇 |
| 1986年 | 80770篇 |
| 1985年 | 76919篇 |
| 1984年 | 57560篇 |
| 1983年 | 48916篇 |
| 1982年 | 29015篇 |
| 1981年 | 25639篇 |
| 1979年 | 53579篇 |
| 1978年 | 37182篇 |
| 1977年 | 31995篇 |
| 1976年 | 29349篇 |
| 1975年 | 31603篇 |
| 1974年 | 38485篇 |
| 1973年 | 36610篇 |
| 1972年 | 34465篇 |
| 1971年 | 32019篇 |
| 1970年 | 30066篇 |
| 1969年 | 28213篇 |
| 1968年 | 25513篇 |
排序方式： 共有10000条查询结果，搜索用时 0 毫秒
31.
Birgitte Lerbæk Rikke Jørgensen Jørgen Aagaard Julie Nordgaard Niels Buus 《Archives of Psychiatric Nursing》2019,33(2):174-181
Background
Life expectancy of people with severe mental illness (SMI) is greatly shortened compared to the general population, and despite extensive research, this issue is unsolved. Although it is widely recognised that people with SMI need support from health care services to manage health related issues, profound health inequalities exist within provision of health care. The aim of this study was to examine how mental health care professionals accounted for their actions and responsibilities related to managing physical health issues among people with SMI.Methods
Three focus groups were conducted with 22 mental health care professionals, employed at three mental health care locations. Participants' situated accounts were subjected to discourse analysis.Results
Participants accounted for actions and responsibilities in three typical ways; 1) by positioning people with SMI as difficult to motivate and actively resisting intervention, 2) by positioning people with SMI as so impaired that intervention was futile, and 3) by arguing they are undertreated for physical conditions and might have physical illnesses that staff are not aware of because of prominent mental illness. These discursive strategies seemed to legitimise situations where participants described not responding to physical health issues, and to downplay potential trouble in situations where participants described not succeeding in facilitating lifestyle changes or promoting compliance to treatment of physical conditions.Discussion and conclusion
Mental health care professionals need to increase their awareness of latent discriminating attitudes towards people with SMI. Such attitudes are suggested to reinforce barriers for people with SMI receiving physical health care. 相似文献32.
Brian Darrith Nicholas B. Frisch Matthew W. Tetreault Michael P. Fice Chris N. Culvern Craig J. Della Valle 《The Journal of arthroplasty》2019,34(2):221-227
Background
Although some prior work supports the safety of same-day arthroplasty performed in a hospital, concerns remain when these procedures are performed in a free-standing ambulatory surgery center. The purpose of this study is to compare 90-day complication rates between matched cohorts that underwent inpatient vs outpatient arthroplasty at an ambulatory surgery center.Methods
A single-surgeon cohort of 243 consecutive patients who underwent outpatient arthroplasty was matched with 243 inpatients who had the same procedure. One-to-one nearest-neighbor matching with respect to gender, age, American Society of Anesthesiologists Score, and body mass index was utilized. The 486 primary arthroplasties included 178 unicondylar knees (36.6%), 146 total hips (30.0%), 92 total knees (18.9%), and 70 hip resurfacings (14.5%). Ninety-day outcomes including reoperation, readmission, unplanned clinic or emergency department visits, and major and minor complications were compared using a 2-sample proportions test.Results
The 2 cohorts were similar in distribution of demographic variables, demonstrating successful matching. The inpatient and outpatient cohorts both had readmission rates of 2.1% (P = 1.0). With the number of subjects studied, there were no statistically significant differences in rates of major complications (2.1% vs 2.5%, P = 1.0), minor complications (7.0% vs 7.8%, P = .86), reoperations (0.4% vs 2.1%, P = .22), emergency department visits (1.6% vs 2.5%, P = .52), or unplanned clinic visits (3.3% vs 5.8%, P = .19).Conclusion
This study suggests that arthroplasty procedures can be performed safely in an ambulatory surgery center among appropriately selected patients without an increased risk of complications. 相似文献33.
Chancellor F. Gray Hernan A. Prieto Justin T. Deen Hari K. Parvataneni 《The Journal of arthroplasty》2019,34(2):206-210
Background
Revision total joint arthroplasty (TJA) is associated with increased readmissions, complications, and expense compared to primary TJA. Bundled payment methods have been used to improve value of care in primary TJA, but little is known of their impact in revision TJA patients. The purpose of this study is to evaluate the impact of a care redesign for a bundled payment model for primary TJA on quality metrics for revision patients, despite absence of a targeted intervention for revisions.Methods
We compared quality metrics for all revision TJA patients including readmission rate, use of post–acute care facility after discharge, length of stay, and cost, between the year leading up to the redesign and the 2 years following its implementation. Changes in the primary TJA group over the same time period were also assessed for comparison.Results
Despite a volume increase of 37% over the study period, readmissions declined from 8.9% to 5.8%. Use of post–acute care facilities decreased from 42% to 24%. Length of stay went from 4.84 to 3.92 days. Cost of the hospital episode declined by 5%.Conclusion
Our health system experienced a halo effect from our bundled payment-influenced care redesign, with revision TJA patients experiencing notable improvements in several quality metrics, though not as pronounced as in the primary TJA population. These changes benefitted the patients, the health system, and the payers. We attribute these positive changes to an altered institutional mindset, resulting from an invested and aligned care team, with active physician oversight over the care episode. 相似文献34.
Katherine M. Stenson Benjamin O. Patterson Matthew Joe Grima Jorg L. De Bruin Peter J.E. Holt Ian Loftus 《Journal of vascular surgery》2019,69(1):53-62.e1
Background
Endovascular aneurysm sealing (EVAS) represents a novel approach to the treatment of abdominal aortic aneurysms. It uses polymer technology to achieve an anatomic seal within the sac of the aneurysm. This cohort study reports the early clinical outcomes, technical refinements, and learning curve during the initial EVAS experience at a single institution.Methods
Results from 150 consecutive EVAS cases for intact, infrarenal abdominal aortic aneurysms are reported here. These cases were undertaken between March 2013 and July 2015. Preoperative, perioperative, and postoperative data were collected for each patient prospectively.Results
The median age of the cohort was 76.6 years (interquartile range, 70.2-80.9 years), and 87.3% were male. Median aneurysm diameter was 62.0 mm (IQR, 58.0-69.0 mm). Adverse neck morphology was seen in 69 (46.0%) patients, including aneurysm neck length <10 mm (17.3%), neck diameter >32 mm or <18 mm (8.7%), and neck angulation >60 degrees (15.3%). Median follow-up was 687 days (IQR, 463-897 days); 37 patients (24.7%) underwent reintervention. The rates of unresolved endoleak are 1.3% type IA, 0.7% type IB, and 2.7% type I. There were no type III endoleaks. There have been seven secondary ruptures in this cohort; all but one of these patients survived after reintervention. Only one rupture occurred in an aneurysm that had been treated within the manufacturer's instructions for use (IFU).Conclusions
The rate of unresolved endoleaks is satisfactorily low. The incidence of secondary rupture is of concern; however, when the IFU are adhered to, the rate is very low. The results of this study suggest that working within the IFU yields better clinical results. 相似文献35.
David C. Johnson Steven S. Raman Sohrab A. Mirak Lorna Kwan Amirhossein M. Bajgiran William Hsu Cleo K. Maehara Preeti Ahuja Izak Faiena Aydin Pooli Amirali Salmasi Anthony Sisk Ely R. Felker David S.K. Lu Robert E. Reiter 《European urology》2019,75(5):712-720
Background
Multiparametric magnetic resonance imaging (mpMRI) undoubtedly affects the diagnosis and treatment of localized prostate cancer (CaP). However, clinicians need a better understanding of its accuracy and limitations in detecting individual CaP foci to optimize management.Objective
To determine the per-lesion detection rate for CaP foci by mpMRI and identify predictors of tumor detection.Design, setting, and participants
We carried out a retrospective analysis of a prospectively managed database correlating lesion-specific results from mpMRI co-registered with whole-mount pathology (WMP) prostatectomy specimens from June 2010 to February 2018. Participants include 588 consecutive patients with biopsy-proven CaP undergoing 3-T mpMRI before radical prostatectomy at a single tertiary institution.Outcome measurements and statistical analysis
We measured mpMRI sensitivity in detecting individual CaP and clinically significant (any Gleason score ≥7) CaP foci and predictors of tumor detection using multivariate analysis.Results and limitations
The final analysis included 1213 pathologically confirmed tumor foci in 588 patients with primarily intermediate- (75%) or high-risk (12%) CaP. mpMRI detected 45% of all lesions (95% confidence interval [CI] 42–47%), including 65% of clinically significant lesions (95% CI 61–69%) and nearly 80% of high-grade tumors. Some 74% and 31% of missed solitary and multifocal tumors, respectively, were clinically significant. The majority of missed lesions were small (61.1% ≤1 cm); 28.3% were between 1 and 2 cm, and 10.4% were >2 cm. mpMRI missed at least one clinically significant focus in 34% of patients overall, and in 45% of men with multifocal lesions. On multivariate analysis, smaller, low-grade, multifocal, nonindex tumors with lower prostate-specific antigen density were more likely to be missed. Limitations include selection bias in a prostatectomy cohort, lack of specificity data, an imperfect co-registration process, and uncertain clinical significance for undetected lesions.Conclusions
mpMRI detects less than half of all and less than two-thirds of clinically significant CaP foci. The moderate per-lesion sensitivity and significant proportion of men with undetected tumor foci demonstrate the current limitations of mpMRI.Patient summary
Magnetic resonance imaging of the prostate before surgical removal for prostate cancer finds less than half of all individual prostate cancer tumors. Large, solitary, aggressive tumors are more likely to be visualized on imaging. 相似文献36.
Sevan Komshian Alik Farber Virendra I. Patel Philip P. Goodney Marc L. Schermerhorn Elizabeth A. Blazick Douglas W. Jones Denis Rybin Gheorghe Doros Jeffrey J. Siracuse 《Journal of vascular surgery》2019,69(2):405-413
Objective
Although endovascular repair of abdominal aortic aneurysms (AAAs) has been demonstrated to have favorable outcomes, not all cohorts of patients with AAA fare equally well. Our goal was to investigate perioperative and 1-year outcomes in patients with end-stage renal disease (ESRD) on dialysis, who have traditionally fared worse after vascular interventions, to assess how ESRD affects outcomes in a large modern cohort of endovascular aneurysm repair (EVAR) patients.Methods
The Vascular Quality Initiative database was queried for all patients undergoing EVAR from 2010 to 2017. ESRD patients were compared with patients not on dialysis. Propensity-matched scoring and multivariable analysis were used to isolate the effects of ESRD.Results
Of 28,683 EVARs identified, there were 321 (1.12%) patients with ESRD on dialysis. Patients with ESRD had no difference in presenting AAA size (57.5 ± 12.7 mm vs 56.7 ± 17.2 mm; P = .44); however, they had more urgent/emergent repairs (20.6% vs 13.6%; P = .002) than those without ESRD. ESRD patients were more often younger, nonwhite, and nonobese and less likely to have commercial insurance (P < .05). ESRD patients more often had hypertension, coronary artery disease, congestive heart failure, previous lower extremity bypass, aneurysm repair, and carotid interventions (P < .05). There was no difference in the rate of concomitant procedures. Matching based on demographics, comorbidities, and operative details showed that ESRD patients had longer hospital length of stay (4.8 ± 9.4 days vs 4.1 ± 12.6 days; P = .026) and higher 30-day mortality (7% vs 2.4%; P < .001). There was no difference in cardiac, pulmonary, lower extremity, bowel, and stroke complications or return to the operating room. On multivariable analysis, ESRD was associated with 30-day mortality (odds ratio, 4.1; 95% confidence interval, 2.6-6.7; P < .001). Of the 24,750 elective EVARs, 1.04% had ESRD on dialysis. Matched data for elective EVAR show increased postoperative length of stay, hospital mortality, and 30-day mortality for ESRD patients on dialysis compared with those who are not. There was no association with postoperative myocardial infarction or pulmonary complications. At 1 year, patients with ESRD on dialysis had worse survival (78% vs 94%; P < .001), and ESRD was associated with higher mortality (hazard ratio, 3.3; 95% confidence interval, 2.5-4.2; P < .001).Conclusions
Among patients undergoing EVAR, ESRD is independently associated with higher perioperative and 1-year mortality despite not being associated with higher postoperative complications. This should be taken into account during informed consent for EVAR and risk-benefit considerations in this high-risk population, particularly for elective repair. 相似文献37.
Anthony J. Bleyer Vincent A. Scavo Samuel E. Wilson Barry J. Browne Brian L. Ferris C. Keith Ozaki Timmy Lee Eric K. Peden Bradley S. Dixon Rick Mishler Timothy P. O&#x;Connor Kendrah Kidd Steven K. Burke 《Journal of vascular surgery》2019,69(2):507-515
Objective
Arteriovenous fistulas created in patients with chronic kidney disease often lose patency and fail to become usable. This prospective trial evaluated the efficacy of vonapanitase, a recombinant human elastase, in promoting radiocephalic fistula patency and use for hemodialysis.Methods
PATENCY-1 was a double-blind, placebo-controlled trial that enrolled 349 patients on or approaching hemodialysis and being evaluated for radiocephalic arteriovenous fistula creation. Of these, 313 were randomized and 311 treated. Patients were assigned to vonapanitase (n = 210) or placebo (n = 103). The study drug solution was applied topically to the artery and vein for 10 minutes immediately after fistula creation. The primary and secondary end points were primary patency (time to first thrombosis or corrective procedure) and secondary patency (time to abandonment). Tertiary end points included use of the fistula for hemodialysis, fistula maturation by ultrasound, and procedure rates.Results
The Kaplan-Meier estimates of 12-month primary patency were 42% (95% confidence interval [CI], 35-49) and 31% (95% CI, 21-42) for vonapanitase and placebo (P = .25). The Kaplan-Meier estimates of 12-month secondary patency were 74% (95% CI, 68-80) and 61% (95% CI, 51-71) for vonapanitase and placebo (P = .048). The proportions of vonapanitase and placebo patients were 39% and 25% (P = .035) with unassisted use for hemodialysis and 64% and 44% (P = .006) with unassisted plus assisted use.Conclusions
Vonapanitase treatment did not significantly improve primary patency but was associated with increased secondary patency and use for hemodialysis. Further research is needed to evaluate these end points. 相似文献38.
S. Kim M.J. Graham R.G. Lee L. Yang S. Kim V. Subramanian J.D. Layne L. Cai R.E. Temel D. Shih A.J. Lusis J.A. Berliner S. Lee 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(3):306-315
Background and aims
Heparin-binding EGF-like growth factor (HB-EGF) is a representative EGF family member that interacts with EGFR under diverse stress environment. Previously, we reported that the HB-EGF-targeting using antisense oligonucleotide (ASO) effectively suppressed an aortic aneurysm in the vessel wall and circulatory lipid levels. In this study, we further examined the effects of the HB-EGF ASO administration on the development of hyperlipidemia-associated atherosclerosis using an atherogenic mouse model.Methods and results
The male and female LDLR deficient mice under Western diet containing 21% fat and 0.2% cholesterol content were cotreated with control and HB-EGF ASOs for 12 weeks. We observed that the HB-EGF ASO administration effectively downregulated circulatory VLDL- and LDL-associated lipid levels in circulation; concordantly, the HB-EGF targeting effectively suppressed the development of atherosclerosis in the aorta. An EGFR blocker BIBX1382 administration suppressed the hepatic TG secretion rate, suggesting a positive role of the HB-EGF signaling for the hepatic VLDL production. We newly observed that there was a significant improvement of the insulin sensitivity by the HB-EGF ASO administration in a mouse model under the Western diet as demonstrated by the improvement of the glucose and insulin tolerances.Conclusion
The HB-EGF ASO administration effectively downregulated circulatory lipid levels by suppressing hepatic VLDL production rate, which leads to effective protection against atherosclerosis in the vascular wall. 相似文献39.
Rachel J. Levene Elza Pollak-Christian Sigrid Wolfram 《The Journal of emergency medicine》2019,56(1):94-96
Background
Cannabis is one of the most abused drugs worldwide, with more than 20 million users in the United States (US). As access to cannabis products increases with expanding US legislation and decriminalization of marijuana, emergency physicians must be adept in recognizing unintentional cannabis toxicity in young children, which can range from altered mental status to encephalopathy and coma.Case Report
We report the case of a 13-month-old female presenting with self-limiting altered mental status and lethargy, with a subsequent diagnosis of tetrahydrocannabinol exposure on confirmatory urine gas chromatography-mass spectrometry.Why Should an Emergency Physician Be Aware of This?
Considering caretakers rarely report possible cannabis exposure, history-taking must review caretakers’ medicinal and recreational drug exposures to prevent inadvertently missing the diagnosis. In the young child with altered mental status, prompt urine screening for cannabinoid detection can prevent further invasive and costly diagnostic investigations, such as brain imaging and lumbar puncture. 相似文献40.
Neuroinflammation is initiated as a result of traumatic brain injury and can exacerbate evolving tissue pathology. Immune cells respond to acute signals from damaged cells, initiate neuroinflammation, and drive the pathological consequences over time. Importantly, the mechanism(s) of injury, the location of the immune cells within the brain, and the animal species all contribute to immune cell behavior following traumatic brain injury. Understanding the signals that initiate neuroinflammation and the context in which they appear may be critical for understanding immune cell contributions to pathology and regeneration.Within this paper, we review a number of factors that could affect immune cell behavior acutely following traumatic brain injury. 相似文献