收费全文 | 1694639篇 |
免费 | 116099篇 |
国内免费 | 5770篇 |
耳鼻咽喉 | 26477篇 |
儿科学 | 50199篇 |
妇产科学 | 44726篇 |
基础医学 | 215982篇 |
口腔科学 | 45176篇 |
临床医学 | 157791篇 |
内科学 | 346229篇 |
皮肤病学 | 40027篇 |
神经病学 | 140261篇 |
特种医学 | 68146篇 |
外国民族医学 | 448篇 |
外科学 | 276558篇 |
综合类 | 33552篇 |
现状与发展 | 78篇 |
一般理论 | 602篇 |
预防医学 | 113313篇 |
眼科学 | 39279篇 |
药学 | 114811篇 |
35篇 | |
中国医学 | 3279篇 |
肿瘤学 | 99539篇 |
2021年 | 14844篇 |
2019年 | 14764篇 |
2018年 | 23539篇 |
2017年 | 19974篇 |
2016年 | 22212篇 |
2015年 | 24150篇 |
2014年 | 37458篇 |
2013年 | 48704篇 |
2012年 | 52795篇 |
2011年 | 55328篇 |
2010年 | 38647篇 |
2009年 | 40717篇 |
2008年 | 52553篇 |
2007年 | 54691篇 |
2006年 | 57082篇 |
2005年 | 53335篇 |
2004年 | 50929篇 |
2003年 | 47872篇 |
2002年 | 47015篇 |
2001年 | 68646篇 |
2000年 | 69248篇 |
1999年 | 59938篇 |
1998年 | 20282篇 |
1997年 | 18422篇 |
1996年 | 17491篇 |
1995年 | 16512篇 |
1994年 | 14431篇 |
1992年 | 44801篇 |
1991年 | 43314篇 |
1990年 | 42156篇 |
1989年 | 41183篇 |
1988年 | 38429篇 |
1987年 | 37679篇 |
1986年 | 36235篇 |
1985年 | 34325篇 |
1984年 | 26094篇 |
1983年 | 22175篇 |
1982年 | 13983篇 |
1979年 | 24585篇 |
1978年 | 17795篇 |
1977年 | 15559篇 |
1976年 | 13934篇 |
1975年 | 15787篇 |
1974年 | 18548篇 |
1973年 | 17986篇 |
1972年 | 17221篇 |
1971年 | 16010篇 |
1970年 | 15219篇 |
1969年 | 14491篇 |
1968年 | 13527篇 |
Prolonged mechanical ventilation (MV) is a major complication following cardiac surgery. We conducted a secondary analysis of the Transfusion Requirements in Cardiac Surgery (TRICTS) III trial to describe MV duration, identify factors associated with prolonged MV, and examine associations of prolonged MV with mortality and complications.
MethodsFour thousand, eight hundred and nine participants undergoing cardiac surgery at 71 hospitals worldwide were included. Prolonged MV was defined based on the Society of Thoracic Surgeons definition as MV lasting 24 hr or longer. Adjusted associations of patient and surgical factors with prolonged MV were examined using multivariable logistic regression. Associations of prolonged MV with complications were assessed using odds ratios, and adjusted associations between prolonged MV and mortality were evaluated using multinomial regression. Associations of shorter durations of MV with survival and complications were explored.
ResultsProlonged MV occurred in 15% (725/4,809) of participants. Prolonged MV was associated with surgical factors indicative of complexity, such as previous cardiac surgery, cardiopulmonary bypass duration, and separation attempts; and patient factors such as critical preoperative state, left ventricular impairment, renal failure, and pulmonary hypertension. Prolonged MV was associated with perioperative but not long-term complications. After risk adjustment, prolonged MV was associated with perioperative mortality; its association with long-term mortality among survivors was weaker. Shorter durations of MV were not associated with increased risk of mortality or complications.
ConclusionIn this substudy of the TRICS III trial, prolonged MV was common after cardiac surgery and was associated with patient and surgical risk factors. Although prolonged MV showed strong associations with perioperative complications and mortality, it was not associated with long-term complications and had weaker association with long-term mortality among survivors.
Study registrationwww.ClinicalTrials.gov (NCT02042898); registered 23 January 2014. This is a substudy of the Transfusion Requirements in Cardiac Surgery (TRICS) III trial.
相似文献- Download : Download high-res image (131KB)
- Download : Download full-size image
- Download : Download high-res image (251KB)
- Download : Download full-size image
- Download : Download high-res image (451KB)
- Download : Download full-size image
To determine frequencies, interlaboratory reproducibility, clinical ratings, and prognostic implications of neural antibodies in a routine laboratory setting in patients with suspected neuropsychiatric autoimmune conditions.
MethodsEarliest available samples from 10,919 patients were tested for a broad panel of neural antibodies. Sera that reacted with leucine-rich glioma-inactivated protein 1 (LGI1), contactin-associated protein-2 (CASPR2), or the voltage-gated potassium channel (VGKC) complex were retested for LGI1 and CASPR2 antibodies by another laboratory. Physicians in charge of patients with positive antibody results retrospectively reported on clinical, treatment, and outcome parameters.
ResultsPositive results were obtained for 576 patients (5.3%). Median disease duration was 6 months (interquartile range 0.6–46 months). In most patients, antibodies were detected both in CSF and serum. However, in 16 (28%) patients with N-methyl-d-aspartate receptor (NMDAR) antibodies, this diagnosis could be made only in cerebrospinal fluid (CSF). The two laboratories agreed largely on LGI1 and CASPR2 antibody diagnoses (κ = 0.95). The clinicians (413 responses, 71.7%) rated two-thirds of the antibody-positive patients as autoimmune. Antibodies against the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR), NMDAR (CSF or high serum titer), γ-aminobutyric acid-B receptor (GABABR), and LGI1 had ≥ 90% positive ratings, whereas antibodies against the glycine receptor, VGKC complex, or otherwise unspecified neuropil had ≤ 40% positive ratings. Of the patients with surface antibodies, 64% improved after ≥ 3 months, mostly with ≥ 1 immunotherapy intervention.
ConclusionsThis novel approach starting from routine diagnostics in a dedicated laboratory provides reliable and useful results with therapeutic implications. Counseling should consider clinical presentation, demographic features, and antibody titers of the individual patient.
相似文献