全文获取类型
收费全文 | 976975篇 |
免费 | 69707篇 |
国内免费 | 1522篇 |
专业分类
耳鼻咽喉 | 13346篇 |
儿科学 | 25818篇 |
妇产科学 | 24376篇 |
基础医学 | 139124篇 |
口腔科学 | 28849篇 |
临床医学 | 85480篇 |
内科学 | 192690篇 |
皮肤病学 | 20091篇 |
神经病学 | 77650篇 |
特种医学 | 37873篇 |
外国民族医学 | 79篇 |
外科学 | 156024篇 |
综合类 | 18409篇 |
现状与发展 | 1篇 |
一般理论 | 291篇 |
预防医学 | 67207篇 |
眼科学 | 21917篇 |
药学 | 75415篇 |
27篇 | |
中国医学 | 2246篇 |
肿瘤学 | 61291篇 |
出版年
2021年 | 7798篇 |
2019年 | 7594篇 |
2018年 | 10882篇 |
2017年 | 8316篇 |
2016年 | 9202篇 |
2015年 | 10435篇 |
2014年 | 13904篇 |
2013年 | 19985篇 |
2012年 | 28045篇 |
2011年 | 28951篇 |
2010年 | 16794篇 |
2009年 | 16007篇 |
2008年 | 27391篇 |
2007年 | 28453篇 |
2006年 | 29121篇 |
2005年 | 27870篇 |
2004年 | 26729篇 |
2003年 | 25529篇 |
2002年 | 24784篇 |
2001年 | 54907篇 |
2000年 | 56676篇 |
1999年 | 47149篇 |
1998年 | 11062篇 |
1997年 | 9713篇 |
1996年 | 9796篇 |
1995年 | 9092篇 |
1994年 | 8400篇 |
1993年 | 7708篇 |
1992年 | 35548篇 |
1991年 | 33974篇 |
1990年 | 32788篇 |
1989年 | 31924篇 |
1988年 | 29041篇 |
1987年 | 28286篇 |
1986年 | 26325篇 |
1985年 | 25177篇 |
1984年 | 17879篇 |
1983年 | 15186篇 |
1982年 | 7828篇 |
1979年 | 15798篇 |
1978年 | 10611篇 |
1977年 | 9072篇 |
1976年 | 7878篇 |
1975年 | 8636篇 |
1974年 | 10471篇 |
1973年 | 9866篇 |
1972年 | 9360篇 |
1971年 | 8857篇 |
1970年 | 8427篇 |
1969年 | 7926篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Davide Fiore Bavaro Flavia Balena Luigi Ronga Fabio Signorile Federica Romanelli Stefania Stolfa Eleonora Sparapano Carmela De Carlo Adriana Mosca Laura Monno Gioacchino Angarano Annalisa Saracino 《Journal de Mycologie Médicale》2022,32(1):101206
An increased number of patients is at risk of Candida spp. bloodstream infection (CBSI) in modern medicine. Moreover, the rising of antifungal resistance (AR) was recently reported. All consecutive CBSI occurred in our Hospital (consisting of 1,370 beds) between 2015 and 2018, were reviewed. For each case, Candida species, AR pattern, ward involved and demographic data of patients were recorded. Overall, 304 episodes of CBSI occurred, with a median (q1:first-,q3:third quartile) of 77 (71-82) CBSI/year. Over the years, a significant increase of CBSI due to C. albicans compared to non-albicans strains was recorded in medical wards (from 65% to 71%, p=0.030), while this ratio remained stable in others. An increase of resistant strains to multiple antifungals such as C. guillermondii was noticed in recent years (from 0% to 9.8%, p=0.008). Additionally, from 2015 to 2018 an increase in fluconazole-resistance was recorded in our Hospital (from 7.4% to 17.4%, p=0.025) and a slight increase in voriconazole-resistance (from 0% to 7% in 2018, p=0.161) was observed, while resistance to echinocandin and amphotericin B remained firmly below 2%.This study suggests a rapid spread of antifungal resistance in our Hospital; therefore, an appropriate antifungal stewardship programs is urgently warranted. 相似文献
2.
3.
A. D. Kane J. Soar R. A. Armstrong E. Kursumovic M. T. Davies F. C. Oglesby L. Cortes C. Taylor I. K. Moppett S. Agarwal J. Cordingley J. Dorey S. J. Finney G. Kunst D. N. Lucas G. Nickols R. Mouton J. P. Nolan B. Patel V. J. Pappachan F. Plaat B. R. Scholefield J. H. Smith L. Varney T. M. Cook collaborators 《Anaesthesia》2023,78(6):701-711
Detailed contemporary knowledge of the characteristics of the surgical population, national anaesthetic workload, anaesthetic techniques and behaviours are essential to monitor productivity, inform policy and direct research themes. Every 3–4 years, the Royal College of Anaesthetists, as part of its National Audit Projects (NAP), performs a snapshot activity survey in all UK hospitals delivering anaesthesia, collecting patient-level encounter data from all cases under the care of an anaesthetist. During November 2021, as part of NAP7, anaesthetists recorded details of all cases undertaken over 4 days at their site through an online survey capturing anonymous patient characteristics and anaesthetic details. Of 416 hospital sites invited to participate, 352 (85%) completed the activity survey. From these, 24,177 reports were returned, of which 24,172 (99%) were included in the final dataset. The work patterns by day of the week, time of day and surgical specialty were similar to previous NAP activity surveys. However, in non-obstetric patients, between NAP5 (2013) and NAP7 (2021) activity surveys, the estimated median age of patients increased by 2.3 years from median (IQR) of 50.5 (28.4–69.1) to 52.8 (32.1–69.2) years. The median (IQR) BMI increased from 24.9 (21.5–29.5) to 26.7 (22.3–31.7) kg.m–2. The proportion of patients who scored as ASA physical status 1 decreased from 37% in NAP5 to 24% in NAP7. The use of total intravenous anaesthesia increased from 8% of general anaesthesia cases to 26% between NAP5 and NAP7. Some changes may reflect the impact of the COVID-19 pandemic on the anaesthetic population, though patients with confirmed COVID-19 accounted for only 149 (1%) cases. These data show a rising burden of age, obesity and comorbidity in patients requiring anaesthesia care, likely to impact UK peri-operative services significantly. 相似文献
4.
M.S. Iqbal G. Vashisht R. McMenemin P. Atherton F. McDonald T. Simmons A. Bradshaw J. Kovarik H. Turnbull L. Dodd P. Mulvenna A. Greystoke 《Clinical oncology (Royal College of Radiologists (Great Britain))》2019,31(2):e1-e10
Aims
Concomitant chemoradiation is the standard of care in patients with inoperable non-small cell lung cancer. The purpose of this study was to analyse the survival outcome and toxicity data of using hypofractionated chemoradiation.Materials and methods
One hundred patients were treated from June 2011 to November 2016. Treatment consisted of 55 Gy in 20 daily fractions concurrently with split-dose cisplatin vinorelbine chemotherapy over 4 weeks followed by two cycles of cisplatin vinorelbine only. Survival was estimated using Kaplan–Meier and Cox regression was carried out for known prognostic factors. A systematic search of literature was conducted using Medline, Embase and Cochrane databases and relevant references included.Results
In total, 97% of patients completed radiotherapy and 73% of patients completed all four cycles of chemotherapy. One patient died of a cardiac event during consolidative chemotherapy. There were two cases of grade 4 toxicities (one sepsis, one renal impairment). Grade 3 toxicities included nausea/vomiting (17%), oesophagitis (15%), infection with neutropenia (12%) and pneumonitis (4%). Clinical benefit was seen in 86%. Two-year progression-free survival and overall survival rates were 49% and 58%, respectively. The median progression-free survival and overall survival were 23.4 and 43.4 months, respectively. The only significant prognostic factor was the number of chemotherapy cycles received (P = 0.02). The systematic review identified 13 relevant studies; a variety of regimens were assessed with variable reporting of outcomes and toxicity but with overall an improvement in survival over time.Conclusion
Our experience compared with the original phase II trial showed improved treatment completion rates and survival with acceptable morbidity. With appropriate patient selection this regimen is an effective treatment option for locally advanced non-small cell lung cancer. This study helps to benchmark efficacy and toxicity rates while considering the addition of new agents to hypofractionated concurrent chemoradiotherapy. The agreement of a standard regimen for assessment in future trials would be beneficial. 相似文献5.
T. Steinmeier S. Schulze Schleithoff B. Timmermann 《Clinical oncology (Royal College of Radiologists (Great Britain))》2019,31(3):142-150
Aims
Childhood cancer is rare and survival of childhood cancer has increased up to 80% at 5 years after diagnosis. Radiotherapy is an important element of the multimodal treatment concept. However, due to growing tissue, children are particularly sensitive to radiation-related side-effects and the induction of secondary malignancies. However, radiotherapy techniques have continuously progressed. In addition, modern treatment concepts have been improved in order to minimise long-term effects. Today, radiotherapy is used for various tumour types in childhood, such as sarcomas and tumours of the central nervous system.Materials and methods
External beam therapy with either photons or protons and brachytherapy are predominantly used for the treatment of childhood tumours. Technical developments and features, as well as clinical outcomes, for several tumour entities are presented.Results
The development of radiotherapy techniques, as well as risk-adapted therapy concepts, resulted in promising outcome regarding tumour control, survival and therapy-related side-effects. It is assumed that proton therapy will be increasingly used for treating children in the future. However, more data have to be collected through multi-institutional registries in order to strengthen the evidence.Conclusion
The development of radiotherapy techniques is beneficial for children in terms of reducing dose exposure. As compared with other modern and highly conformal techniques, particularly proton therapy may achieve high survival rates and tumour control rates while decreasing the risk for side-effects. However, clinical evidence for modern radiotherapy techniques is still limited today. An optimal patient triaging with the selection of the most appropriate radiation technique for each individual patient will be an important goal for the future. 相似文献6.
Joshua R. Labott Cody C. Wyles Matthew T. Houdek Megha M. Tollefson David J. Driscoll William J. Shaughnessy Rafael J. Sierra 《The Journal of arthroplasty》2019,34(4):682-685
Background
Klippel-Trénaunay syndrome (KTS) is a severe vascular malformation that can lead to hypertrophic osteoarthritis. Total knee arthroplasty (TKA) performed in extremities affected with KTS is challenging given the high-risk vascular considerations and occasionally poor bone quality.Methods
We identified 12 patients with KTS who underwent TKA between 1998 and 2017. There were 7 men, mean age 42 years, and mean follow-up was 7 years. Before arthroplasty, 2 patients (17%) had preoperative sclerotherapy. Preoperative vascular studies were done for 9 patients (75%) and included magnetic resonance imaging (n = 7), magnetic resonance angiography (n = 1), and computed tomography angiography (n = 1). A preoperative blood conservation protocol was used for all operations and included the use of tranexamic acid (TXA) in later years. Posterior-stabilized TKA was used in 10 cases and cruciate-retaining TKA was used in 2 cases.Results
At final follow-up, 2 patients (17%) had undergone revision surgery: 1 for infection and 1 for tibial loosening with subsequent arthrofibrosis. Knee Society Scores (36-83, P < .0001) and functional scores (48-84, P = .0007) significantly increased between the preoperative and postoperative period. Likewise at last follow-up, the mean knee range of motion significantly increased (82°-104°, P = .04). Median blood loss for patients who received TXA was 200 mL compared to 275 mL in patients who did not receive TXA (P = .66). Likewise there was no difference (P = .5) in the proportion of patients who required a transfusion between those who received TXA (2/6, 33%) and those who did not (3/6, 50%).Conclusion
In this small series, TKA can lead to significant clinical improvement for patients with KTS. Modern blood management techniques and a careful multidisciplinary care approach render TKA a reasonable option for select patients with KTS.Level of Evidence
Level IV case series, therapeutic. 相似文献7.
Tarik D. Madni Paul A. Nakonezny Evan Barrios Jonathan B. Imran Audra T. Clark Luis Taveras Holly B. Cunningham Alana Christie Alexander L. Eastman Christian T. Minshall Stephen Luk Joseph P. Minei Herb A. Phelan Michael W. Cripps 《American journal of surgery》2019,217(1):90-97
Background
The Parkland Grading Scale for Cholecystitis (PGS) was developed as an intraoperative grading scale to stratify gallbladder (GB) disease severity during laparoscopic cholecystectomy (LC). We aimed to prospectively validate this scale as a measure of LC outcomes.Methods
Eleven surgeons took pictures of and prospectively graded the initial view of 317?GBs using PGS while performing LC (LIVE) between 9/2016 and 3/2017. Three independent surgeon raters retrospectively graded these saved GB images (STORED). The Intraclass Correlation Coefficient (ICC) statistic assessed rater reliability. Fisher's Exact, Jonckheere-Terpstra, or ANOVA tested association between peri-operative data and gallbladder grade.Results
ICC between LIVE and STORED PGS grades demonstrated excellent reliability (ICC?=?0.8210). Diagnosis of acute cholecystitis, difficulty of surgery, incidence of partial and open cholecystectomy rates, pre-op WBC, length of operation, and bile leak rates all significantly increased with increasing grade.Conclusions
PGS is a highly reliable, simple, operative based scale that can accurately predict outcomes after LC.Table of contents summary
The Parkland Grading Scale for Cholecystitis was found to be a reliable and accurate predictor of laparoscopic cholecystectomy outcomes. Diagnosis of acute cholecystitis, surgical difficulty, incidence of partial and open cholecystectomy rates, pre-op WBC, operation length, and bile leak rates all significantly increased with increasing grade. 相似文献8.
Inna Y. Gong Nigel S. Tan Sammy H. Ali Gerald Lebovic Muhammad Mamdani Shaun G. Goodman Dennis T. Ko Andreas Laupacis Andrew T. Yan 《The Canadian journal of cardiology》2019,35(5):653-660
Background
Although it is known that women do not participate in trials as frequently as men, there are limited recent data examining how women recruitment has changed over time.Methods
We conducted MEDLINE search using a validated strategy for randomized trials published in New England Journal of Medicine, Lancet, and Journal of the American Medical Association between 1986 and 2015, and included trials evaluating pharmacologic or nonpharmacologic therapies. We abstracted data on demographics, intervention type, clinical indication, and trial design characteristics, and examined their relationships with women enrollment.Results
In total, 598 trials met inclusion criteria. Women enrollment increased significantly over time (21% between 1986 and 1990 to 33% between 2011 and 2015; Pfor trend < 0.001) and did not differ by journal or funding source. Women enrollment varied with clinical indication, comprising 37% for non–coronary artery disease vascular trials, 30% for coronary artery disease trials, 28% for heart failure trials, and 28% for arrhythmia trials (P < 0.001), which were all significantly lower than the expected proportion in disease populations (P < 0.001). Women enrollment varied with trial type (31%, 29%, and 26% for pharmacologic, device, and procedural trials, respectively; P = 0.001). These findings were corroborated using multivariable analysis. We found significant positive correlations between women enrolled, and mean age and total number of participants. Fewer women were enrolled in trials reporting statistically significant results than those who did not (P = 0.001).Conclusions
Although enrollment of women has increased over time, it remains lower than the relative proportion in the disease population. Future studies should elucidate the reasons for persistent under-representation of women in clinical trials. 相似文献9.
Michelle Lerman Julia A. Gaebler Sunday Hoy Jessica Izhakoff Laura Gullett Timothy Niecko Pinar Karaca-Mandic Thomas ODonnell 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10.
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