全文获取类型
| 收费全文 | 2395318篇 |
| 免费 | 196990篇 |
| 国内免费 | 4282篇 |
专业分类
| 耳鼻咽喉 | 34589篇 |
| 儿科学 | 73254篇 |
| 妇产科学 | 63191篇 |
| 基础医学 | 337458篇 |
| 口腔科学 | 67888篇 |
| 临床医学 | 217886篇 |
| 内科学 | 472934篇 |
| 皮肤病学 | 48292篇 |
| 神经病学 | 202459篇 |
| 特种医学 | 96855篇 |
| 外国民族医学 | 886篇 |
| 外科学 | 364030篇 |
| 综合类 | 56414篇 |
| 现状与发展 | 1篇 |
| 一般理论 | 1004篇 |
| 预防医学 | 192307篇 |
| 眼科学 | 55916篇 |
| 药学 | 178891篇 |
| 4篇 | |
| 中国医学 | 4383篇 |
| 肿瘤学 | 127948篇 |
出版年
| 2018年 | 24795篇 |
| 2017年 | 19249篇 |
| 2016年 | 21072篇 |
| 2015年 | 23779篇 |
| 2014年 | 34310篇 |
| 2013年 | 51829篇 |
| 2012年 | 70460篇 |
| 2011年 | 73948篇 |
| 2010年 | 43397篇 |
| 2009年 | 41640篇 |
| 2008年 | 70128篇 |
| 2007年 | 74572篇 |
| 2006年 | 75397篇 |
| 2005年 | 73470篇 |
| 2004年 | 70631篇 |
| 2003年 | 68222篇 |
| 2002年 | 67410篇 |
| 2001年 | 112603篇 |
| 2000年 | 116618篇 |
| 1999年 | 98469篇 |
| 1998年 | 28085篇 |
| 1997年 | 25696篇 |
| 1996年 | 25583篇 |
| 1995年 | 24777篇 |
| 1994年 | 23258篇 |
| 1993年 | 21642篇 |
| 1992年 | 79452篇 |
| 1991年 | 76451篇 |
| 1990年 | 73626篇 |
| 1989年 | 70894篇 |
| 1988年 | 65892篇 |
| 1987年 | 64836篇 |
| 1986年 | 61386篇 |
| 1985年 | 58434篇 |
| 1984年 | 44257篇 |
| 1983年 | 37696篇 |
| 1982年 | 22947篇 |
| 1981年 | 20373篇 |
| 1979年 | 41325篇 |
| 1978年 | 29003篇 |
| 1977年 | 24368篇 |
| 1976年 | 22845篇 |
| 1975年 | 23980篇 |
| 1974年 | 29652篇 |
| 1973年 | 28047篇 |
| 1972年 | 26227篇 |
| 1971年 | 24159篇 |
| 1970年 | 22753篇 |
| 1969年 | 21091篇 |
| 1968年 | 19136篇 |
排序方式： 共有10000条查询结果，搜索用时 15 毫秒
11.
Michelle Lerman Julia A. Gaebler Sunday Hoy Jessica Izhakoff Laura Gullett Timothy Niecko Pinar Karaca-Mandic Thomas O&#x;Donnell Stanley G. Rockson 《Journal of vascular surgery》2019,69(2):571-580
Objective
Phlebolymphedema (chronic venous insufficiency-related lymphedema) is a common and costly condition. Nevertheless, there is a dearth of evidence comparing phlebolymphedema therapeutic interventions. This study sought to examine the medical resource utilization and phlebolymphedema-related cost associated with Flexitouch (FLX; Tactile Medical, Minneapolis, Minn) advanced pneumatic compression devices (APCDs) relative to conservative therapy (CONS) alone, simple pneumatic compression devices (SPCDs), and other APCDs in a representative U.S. population of phlebolymphedema patients.Methods
This was a longitudinal matched case-control analysis of deidentified private insurance claims. The study used administrative claims data from Blue Health Intelligence for the complete years 2012 through 2016. Patients were continuously enrolled for at least 18 months, diagnosed with phlebolymphedema, and received at least one claim for CONS either alone or in addition to pneumatic compression (SPCDs or APCDs). The main outcomes included direct phlebolymphedema- and sequelae-related medical resource utilization and costs.Results
After case matching, the study included 86 patients on CONS (87 on FLX), 34 on SPCDs (23 on FLX), and 69 on other APCDs (67 on FLX). Compared with CONS, FLX was associated with 69% lower per patient per year total phlebolymphedema- and sequelae-related costs net of any pneumatic compression device-related costs ($3839 vs $12,253; P = .001). This was driven by 59% fewer mean annual hospitalizations (0.13 vs 0.32; P < .001) corresponding to 82% lower inpatient costs and 55% lower outpatient hospital costs. FLX was also associated with 52% lower outpatient physical therapy and occupational therapy costs and 56% lower other outpatient-related costs. Compared with SPCDs, FLX was associated with 85% lower total costs ($1153 vs $7449; P = .008) driven by 93% lower inpatient costs ($297 vs $4215; P = .002), 84% lower outpatient hospital costs ($368 vs $2347; P = .020), and 85% lower other outpatient-related costs ($353 vs $2313; P = .023). Compared with APCDs, FLX was associated with 53% lower total costs ($3973 vs $8436; P = .032) because of lower outpatient costs and lower rates of cellulitis (22.4% vs 44.9% of patients; P = .02).Conclusions
This analysis indicates significant benefits attributable to FLX compared with alternative compression therapies that can help reduce the notable economic burden of phlebolymphedema. 相似文献12.
Perinatal hypoxic-ischemic encephalopathy is a leading cause of neonatal death and disability.Therapeutic hypothermia significantly reduces death and major disability associated with hypoxic-ischemic encephalopathy;however,many infants still experience lifelong disabilities to movement,sensation and cognition.Clinical guidelines,based on strong clinical and preclinical evidence,recommend therapeutic hypothermia should be started within 6 hours of birth and continued for a period of 72 hours,with a target brain temperature of 33.5 ±0.5℃ for infants with moderate to severe hypoxic-ischemic encephalopathy.The clinical guidelines also recommend that infants be re warmed at a rate of 0.5℃ per hour,but this is not based on strong evidence.There are no randomized controlled trials investigating the optimal rate of rewarming after therapeutic hypothermia for infants with hypoxic-ischemic encephalopathy.Preclinical studies of rewarming are conflicting and results were confounded by treatment with sub-optimal durations of hypothermia.In this review,we evaluate the evidence for the optimal start time,duration and depth of hypothermia,and whether the rate of rewarming after treatment affects brain injury and neurological outcomes. 相似文献
13.
J. Shin J. Choi K.J. Kim 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(2):144-151
Background and aim
The associations of long-term exposure to particulate matter <10 μm in size (PM10), nitrogen dioxide (NO2), carbon monoxide (CO), sulfur dioxide (SO2), and ozone (O3) with cardiometabolic diseases (CMD) remain uncertain in the Korean population. Therefore, we sought to examine the associations between PM10, NO2, CO, SO2, and O3 and CMD using data collected from the Korean Community Health Survey.Methods and results
We selected 100,867 adults aged 19 years or older who had lived in the same domicile for ≥10 years and surveyed them to collect data on socioeconomic characteristics; health-related behaviors; obesity; and physician-diagnosed CMD history, including hypertension, diabetes mellitus, dyslipidemia, stroke, myocardial infarction, and ischemic heart disease. We calculated interquartile ranges for PM10, NO2, CO, SO2, and O3 from the 10 year average concentrations (2003–2012). Hypertension, diabetes mellitus, and dyslipidemia were positively associated with PM10, NO2, CO, SO2, and O3 after adjusting for confounding factors. Obesity was positively associated with PM10, NO2, SO2, and O3. On the other hand, we found no associations between stroke, myocardial infarction, and ischemic heart disease and exposure to PM10, NO2, CO, SO2, and O3 in these subjects. In subjects aged ≥65 years, the risk of dyslipidemia was markedly increased under exposure to NO2 and CO compared to subjects aged <65 years. The risk of obesity was also significantly increased under exposure to PM10 and NO2. However, sex differences in these associations were not found.Conclusion
Long-term exposure to PM10, NO2, CO, SO2, and O3 may be a risk factor of CMD in Korean adults. 相似文献14.
Julia H. Vermylen Gordon J. Wood Elaine R. Cohen Jeffrey H. Barsuk William C. McGaghie Diane B. Wayne 《Journal of pain and symptom management》2019,57(3):682-687
Introduction
Physician communication impacts patient outcomes. However, communication skills, especially around difficult conversations, remain suboptimal, and there is no clear way to determine the validity of entrustment decisions. The aims of this study were to 1) describe the development of a simulation-based mastery learning (SBML) curriculum for breaking bad news (BBN) conversation skills and 2) set a defensible minimum passing standard (MPS) to ensure uniform skill acquisition among learners.Innovation
An SBML BBN curriculum was developed for fourth-year medical students. An assessment tool was created to evaluate the acquisition of skills involved in a BBN conversation. Pilot testing was completed to confirm improvement in skill acquisition and set the MPS.Outcomes
A BBN assessment tool containing a 15-item checklist and six scaled items was developed. Students' checklist performance improved significantly at post-test compared to baseline (mean 65.33%, SD = 12.09% vs mean 88.67%, SD = 9.45%, P < 0.001). Students were also significantly more likely to have at least a score of 4 (on a five-point scale) for the six scaled questions at post-test. The MPS was set at 80%, requiring a score of 12 items on the checklist and at least 4 of 5 for each scaled item. Using the MPS, 30% of students would require additional training after post-testing.Comments
We developed a SBML curriculum with a comprehensive assessment of BBN skills and a defensible competency standard. Future efforts will expand the mastery model to larger cohorts and assess the impact of rigorous education on patient care outcomes. 相似文献15.
Christopher N. Cooley Tyler J. Beranek Matthew A. Warpinski Robert Alexander Amanda O. Esquivel 《The American journal of emergency medicine》2019,37(2):199-203
Introduction
In the United States there has been a large increase in participation in lacrosse for both males and females. The purpose of this study was to analyze the number of head injuries, injury rates (calculated using the reported number of participants) and types of head injuries that are seen in emergency departments in the United States.Methods
We compared injuries between male and female lacrosse participants. This was a retrospective study using a publicly available database produced by the US Consumer Product Safety Commission and information about lacrosse participation from US Lacrosse.Results
A linear regression was performed and showed a positive correlation between number of head injuries to males and time from 2002 to 2010 (R2?=?0.823; p?=?0.001). While the number of injuries to the head in female lacrosse participants was not significant. There was a negative correlation between the number of head injuries to males from 2010 to 2016 (R2?=?0.800; p?=?0.007), but again, there was no significance for female injury count (R2?=?0.417; p?=?0.117). Other significant differences between head injuries in males and females included the mechanism of injury and the type of injury recorded.Conclusion
The most recent data from 2010 to 2016, suggest that both males and females have had a decrease in injury rate. However the total number of female head injuries is not significantly decreasing and as the sport continues to grow there will likely be more total head injuries and visits to the emergency department. 相似文献16.
Sophia A. Traven Russell A. Reeves Molly G. Sekar Harris S. Slone Zeke J. Walton 《The Journal of arthroplasty》2019,34(1):140-144
Background
While the 11-factor modified frailty index (mFI) has been shown to predict adverse outcomes in patients undergoing total joint arthroplasty, the 5-factor index has not been evaluated in this patient population. The goal of this study was to evaluate the utility of the mFI-5 as a predictor of morbidity and mortality in patients undergoing primary total hip and knee arthroplasty.Methods
A retrospective analysis of the American College of Surgeons National Surgical Quality Improvement Program's database for patients undergoing total hip arthroplasty and total knee arthroplasty between the years 2005 and 2016 was conducted. The 5-factor score, which includes the presence of comorbid diabetes, hypertension, congestive heart failure, chronic obstructive pulmonary disease, and functional status, was calculated for each patient. Multivariate logistic regression models were used to assess the relationship between the mFI-5 and postoperative complications while controlling for demographic variables.Results
One hundred forty thousand one hundred fifty-eight patients undergoing total hip arthroplasty and 226,398 patients undergoing total knee arthroplasty were identified. After adjusting for demographic variables and comorbid conditions, logistic regression analyses revealed that the mFI-5 was a strong predictor for total complications, Clavien-Dindo grade IV complications (cardiac arrest, myocardial infarction, septic shock, pulmonary embolism, postoperative dialysis, reintubation, and prolonged ventilator requirement), surgical site infections, readmission, and 30-day mortality (P < .001).Conclusions
The mFI-5 is an independent predictor of postoperative complications including life-threatening medical complications, surgical site infections, hospital readmission, and 30-day mortality after primary hip and knee arthroplasty. This clinical tool can be used to identify high-risk surgical patients and guide preoperative counseling to optimize outcomes.Level of Evidence
III. 相似文献17.
Arne de Niet Michel M.P.J. Reijnen Clark J. Zeebregts 《Journal of vascular surgery》2019,69(2):348-356
Objective
The objective of this study was to investigate the feasibility of a specific custom-made fenestrated aortic cuff in the treatment of complex abdominal aortic aneurysms (AAAs).Methods
Between 2013 and 2016, a total of 57 custom-made Fenestrated Anaconda (Vascutek, Inchinnan, Scotland, UK) aortic cuffs were placed in 38 centers worldwide. All centers were invited to participate in this retrospective analysis. Postoperative and follow-up data included the presence of adverse events, necessity for reintervention, and renal function.Results
Fifteen clinics participated, leading to 29 cases. Median age at operation was 74 years (interquartile range [IQR], 71-78 years); five patients were female. Two patients were treated for a para-anastomotic AAA after open AAA repair, 19 patients were treated because of a complicated course after primary endovascular AAA repair, and 8 cases were primary procedures for AAA. A total of 76 fenestrations (mean, 2.6 per case) were used. Four patients needed seven adjunctive procedures. Two patients underwent conversion, one because of a dissection of the superior mesenteric artery and one because of perforation of a renal artery. Median operation time was 225 minutes (IQR, 150-260 minutes); median blood loss, 200 mL (IQR, 100-500 mL); and median contrast volume, 150 mL (IQR, 92-260 mL). Primary technical success was achieved in 86% and secondary technical success in 93%. The 30-day morbidity was 7 of 29 with a mortality rate of 4 of 29. Estimated glomerular filtration rate remained unchanged before and after surgery (76 to 77 mL/min/m2). Between preoperative and median follow-up of 11 months, estimated glomerular filtration rate was reduced statistically significantly (76 to 63 mL/min/m2). During follow-up, 9 cases had an increase in aneurysm sac diameter (5 cases >5 mm); 14 cases had a stable or decreased aneurysm sac diameter; and in 2 cases, no aneurysm size was reported. No type I endoleak was reported, and two cases with a type III endoleak were treated by endovascular means during follow-up. Survival, reintervention-free survival, and target vessel patency at 1 year were 81% ± 8%, 75% ± 9%, and 99% ± 1%, respectively. After 2 years, these numbers were 81% ± 8%, 67% ± 11%, and 88% ± 6%, respectively. During follow-up, the two patients with a type III endoleak needed endograft-related reinterventions.Conclusions
Treatment with this specific custom-made fenestrated aortic cuff is feasible after complicated previous (endovascular) aortic repair or in complex AAAs. The complexity of certain AAA cases is underlined in this study, and the Fenestrated Anaconda aortic cuff is a valid option in selected cases in which few treatment options are left. 相似文献18.
Javed Butler Mei Yang Massimiliano Alfonzo Manzi Gregory P. Hess Mahesh J. Patel Thomas Rhodes Michael M. Givertz 《Journal of the American College of Cardiology》2019,73(8):935-944
Background
Epidemiology of patients with worsening heart failure and reduced ejection fraction (HFrEF) in the real-world setting is not well described.Objectives
The purpose of this study was to describe incidence, clinical characteristics, treatment, and outcomes of patients with HFrEF who develop worsening heart failure (HF) in the real-world setting.Methods
Data on patients with incident HFrEF from the National Cardiovascular Data Registry PINNACLE were linked to pharmacy, private practitioner, and hospital claims databases. Incidence, clinical characteristics, treatment (angiotensin-converting enzyme inhibitor/angiotensin receptor blocker, beta-blocker, and mineralocorticoid receptor antagonist) and outcomes of patients with worsening HF, defined as ≥90 days of stable HF with subsequent worsening requiring intravenous diuretic agents, were assessed.Results
Of 11,064 HFrEF patients, 1,851 (17%) developed worsening HF on average 1.5 years following initial HF diagnosis. Patients who developed worsening HF were more likely to be African American, be octogenarians, and have higher comorbidity burden (p < 0.001). At the onset of worsening HF, 42.4% of patients were on monotherapy, 43.4% were on dual therapy, and 14.1% were on triple therapy. A total of 48%, 61%, and 98% of patients were on >50% target dose for angiotensin-converting enzyme inhibitor/angiotensin receptor blocker, beta-blocker, and mineralocorticoid receptor antagonist, respectively. The 2-year mortality rate was 22.5%, and 56% of patients were rehospitalized within 30 days of the worsening HF event.Conclusions
In the real-world setting, 1 in 6 patients with HFrEF develop worsening HF within 18 months of HF diagnosis. These patients have a high risk for 2-year mortality and recurrent HF hospitalizations. The use of standard-of-care therapies both before and after the onset of worsening HF is low. With high unmet medical need, patients with worsening HF require novel treatment strategies as well as greater optimization of existing guideline-directed therapy. 相似文献19.
20.
Optimizing glycemic control remains a shared challenge for clinicians and their patients with diabetes. Flash continuous glucose monitoring (CGM) provides immediate information about an individual’s current and projected glucose level, allowing users to respond promptly to mitigate or prevent pending hypoglycemia or hyperglycemia. Large randomized controlled trials (RCTs) have demonstrated the glycemic benefits of flash CGM use in both type 1 and type 2 diabetes. However, whereas RCTs are mostly focused on the efficacy of this technology in defined circumstances, real-world studies can assess its effectiveness in wider clinical settings. This review assesses the most recent real-world studies demonstrating the effectiveness of flash CGM use to improve clinical outcomes and health care resource utilization in populations with diabetes.During the past 5 years, increasing numbers of people with type 1 or type 2 diabetes have integrated continuous glucose monitoring (CGM) into their diabetes self-management regimens. Unlike traditional blood glucose meters, CGM systems provide immediate information about the concentration and the direction and rate of change of interstitial glucose. This information enables patients to intervene promptly to prevent or reduce acute hypoglycemia or hyperglycemia.Flash CGM is among the most recent CGM technologies. Currently, the FreeStyle Libre 14-day system (Abbott Diabetes Care) and FreeStyle Libre 2 are the only flash CGM systems available, and these systems are being adopted rapidly. Large randomized controlled trials (RCTs) have confirmed the glycemic benefits of flash CGM use in people with type 1 diabetes (1,2) and those with type 2 diabetes (3–6). However, because RCTs are mostly focused on measures of efficacy in defined circumstances, real-world studies can usefully assess the effectiveness of flash CGM in wider clinical settings.Although adoption of flash CGM continues to expand within endocrinology and diabetes specialty practices, primary care providers may be less familiar with this technology and how it can benefit patients with diabetes. This review assesses recent real-world studies demonstrating the impact of flash CGM use on clinical outcomes and health care resource utilization in both type 1 and type 2 diabetes populations. 相似文献