全文获取类型
收费全文 | 4997篇 |
免费 | 298篇 |
国内免费 | 58篇 |
专业分类
耳鼻咽喉 | 29篇 |
儿科学 | 312篇 |
妇产科学 | 140篇 |
基础医学 | 523篇 |
口腔科学 | 222篇 |
临床医学 | 469篇 |
内科学 | 1108篇 |
皮肤病学 | 73篇 |
神经病学 | 138篇 |
特种医学 | 408篇 |
外科学 | 838篇 |
综合类 | 97篇 |
一般理论 | 2篇 |
预防医学 | 240篇 |
眼科学 | 101篇 |
药学 | 338篇 |
1篇 | |
中国医学 | 31篇 |
肿瘤学 | 283篇 |
出版年
2023年 | 38篇 |
2022年 | 95篇 |
2021年 | 133篇 |
2020年 | 101篇 |
2019年 | 127篇 |
2018年 | 159篇 |
2017年 | 107篇 |
2016年 | 134篇 |
2015年 | 153篇 |
2014年 | 182篇 |
2013年 | 249篇 |
2012年 | 294篇 |
2011年 | 308篇 |
2010年 | 189篇 |
2009年 | 213篇 |
2008年 | 240篇 |
2007年 | 239篇 |
2006年 | 228篇 |
2005年 | 225篇 |
2004年 | 196篇 |
2003年 | 168篇 |
2002年 | 149篇 |
2001年 | 68篇 |
2000年 | 63篇 |
1999年 | 70篇 |
1998年 | 125篇 |
1997年 | 140篇 |
1996年 | 129篇 |
1995年 | 92篇 |
1994年 | 96篇 |
1993年 | 108篇 |
1992年 | 28篇 |
1991年 | 25篇 |
1990年 | 30篇 |
1989年 | 54篇 |
1988年 | 48篇 |
1987年 | 32篇 |
1986年 | 45篇 |
1985年 | 42篇 |
1984年 | 23篇 |
1983年 | 21篇 |
1982年 | 26篇 |
1981年 | 40篇 |
1980年 | 23篇 |
1979年 | 10篇 |
1978年 | 16篇 |
1977年 | 24篇 |
1976年 | 24篇 |
1975年 | 8篇 |
1969年 | 3篇 |
排序方式: 共有5353条查询结果,搜索用时 15 毫秒
81.
PAG Torrie A Leonidou IJ Harding G Wynne Jones MJ Hutchinson IW Nelson 《Annals of the Royal College of Surgeons of England》2013,95(8):604-608
Introduction
The purpose of this study was to investigate the significance of the inflammatory markers on admission in the isolation of a causative pathogen in patients with spinal infection. Spinal infection is treated frequently at spinal units and can encompass a broad range of clinical entities. Its diagnosis is often delayed because of the difficulty of identifying the responsible pathogen.Methods
Patients with spinal infection treated in our institution over a period of eight years were identified and their notes studied retrospectively. Admission C-reactive protein (CRP), white cell count (WCC) as well as co-morbidities and mode of pathogen identification were recorded. Overall, 96 patients were included in the study.Results
The CRP levels on admission were correlated significantly with the overall potential for isolation of a pathogen (p<0.0001) and positive biopsy cultures (p=0.0016). Admission WCC levels were associated significantly with the overall potential for isolation of a pathogen (p=0.0003) and positive biopsy cultures (p=0.0023). Both CRP and WCC levels were significantly negatively correlated with the duration of the preceding symptoms (p=0.0003 and p<0.0001 respectively). Delay in presentation was significantly negatively correlated with organism isolation (p=0.0001). Multivariate analyses identified the delay in presentation as the strongest independent variable for organism isolation (p=0.014) in cases of spontaneous spinal infection when compared with the admission CRP level (p=0.031) and WCC (p=0.056).Conclusions
In spontaneous spinal infection, delay in presentation is the strongest independent variable for organism isolation. High inflammatory marker levels on admission are a useful prognostic marker for the overall potential of isolating a causative organism either by blood cultures or by biopsy in patients with negative blood cultures. Furthermore, the admission inflammatory marker levels allow for treating surgeons to counsel their patients of the likelihood of achieving a positive microbiological yield from biopsy. 相似文献82.
It has been observed that operating the intra‐aortic balloon at an angle to the horizontal resulted in a reduction of the volume displaced toward the coronary arteries and compromised afterload reduction. Therefore, the aim of this work is to examine whether changing the current balloon shape, which has not been altered for 40 years, could compensate for the negative hemodynamic effects due to angulation. We tested two tapered balloons, increasing diameter (TID) and decreasing diameter (TDD), and compared the results with those obtained from a standard cylindrical balloon. The balloons were tested in vitro at 60 beats/min and a static pressure of 90 mm Hg. The balloons were operated at four angles (0°, 20°, 30°, 45°), and the pressure at three locations along the balloon (base, middle, and tip) was also measured. Flow rate upstream of the tip of the balloon was also measured to indicate the flow displaced toward the coronary circulation. The relative volume displaced toward (VUTVi) and suctioned away from (VUTVd) the simulated ascending aorta, during inflation and deflation, respectively, is reduced when a standard cylindrical balloon is operated at an angle to the horizontal. The TDD provided the greatest VUTVi and also produced the largest pulse pressure during deflation. Although the TID provided less VUTVi and VUTVd at smaller angles, it was not markedly affected by the change of angle. According to these results, different balloon shapes analyzed, with comparable volume to that of a cylindrical balloon, produced greater inflation and deflation benefits, at the horizontal and at a range of angles to the horizontal. Further investigations are required to optimize the shape of the tapered balloons to fit into the available physiological space. 相似文献
83.
84.
BackgroundSpinal anesthesia is gradually increasing in ambulatory setting. The limiting factor to the more widespread use of spinal anesthesia in the outpatient setting refers to the effect of residual block. Selective spinal anesthesia (SSA) with low dose lidocaine was compared with modern general anesthesia (GA) technique in day care anorectal surgeries.ObjectiveOur objectives in this study was to compare SSA with propofol and fentanyl based modern GA as regard to 1 – operating conditions 2 – patients’ and surgeon’s satisfaction, 3 – intraoperative, postoperative adverse events and 4 – recovery profiles in ambulatory anorectal surgeries.MethodsProspective randomized clinical study was conducted on 60 patients undergoing elective day case anorectal surgery. The patients were randomly allocated into one of two groups (GA and SSA groups) of 30 patients each. In GA group anesthesia was induced with intravenous fentanyl (2 μg/kg) and propofol (2–3 mg/kg). Airway was secured with I-gel supraglottic airway. Anesthesia was maintained by sevoflurane 1.5–2%, nitrous oxide 60% in oxygen mixture. SSA group patients received spinal anesthesia with lidocaine 20 mg and fentanyl 25 μg to a total volume of 3 ml with sterile water for injection. Intraoperative, postoperative and home adverse events, time to ambulate, time to home discharge, patients’ and surgeon’s satisfactions were statistically compared between both groups.ResultsBoth anesthetic techniques showed acceptable operating conditions and high rate of patients’ satisfaction. Low pain intensity, shorter time to ambulate and home discharge in SSA compared to GA with a p value < 0.001. Intraoperative hemodynamic stability was reported in both groups. No major postoperative or home adverse events in both groups.ConclusionsSSA with low dose lidocaine may be suitable alternative and competitive for modern GA in ambulatory anorectal surgery. 相似文献
85.
86.
Ali Ashraf A. Noelle Larson Gabriela Ferski Cary H. Mielke Nicholas M. Wetjen Kenneth J. Guidera 《Journal of children's orthopaedics》2013,7(3):183-194
Purpose
Children with multiple hereditary exostoses (MHE) have numerous osteochondromas, with the most prominent lesions typically over the appendicular skeleton. A recent report noted a high rate of intracanal lesions in this patient population and recommended preventative spinal screening with magnetic resonance imaging (MRI) or computed tomography (CT). We sought to evaluate the prevalence of spinal stenosis from intracanal osteochondromas at our pediatric orthopedic center in order to evaluate if routine screening is warranted.Methods
All pediatric patients treated for MHE were retrospectively identified. Records were reviewed to determine demographics, previous orthopedic surgery, and indication and results of axial spine imaging (CT or MRI). Imaging studies were reviewed to evaluate the presence of intracanal and compressive spinal lesions.Results
Between 1990 and 2011, axial imaging was performed in nine patients with MHE due to concerns of pain, weakness, and/or dizziness. These patients had moderate disease involvement, with a mean of 4.9 previous orthopedic surgeries to address skeletal osteochondromas. Two patients with MHE had cervical spinal stenosis secondary to intracanal osteochondromas. Both children successfully underwent spinal decompression. Thus, of our MHE population undergoing axial imaging, 22 % were noted to have intracanal lesions.Conclusions
Our experience reveals a >20 % rate of compressive intracanal osteochondromas in MHE patients undergoing spinal imaging. These two patients represent 5 % of the MHE patients treated at our center. These lesions may be slow growing, and significant consequences can occur if not identified promptly. Thus, we confer that routine axial screening of the spinal canal may be warranted in these children. 相似文献87.
Bishara S. Atiyeh Hussein A. Hashim Michel T. Rubeiz Ashraf M. Hamdan Fadi F. Bitar Haytham M. Serhal 《Journal of plastic surgery and hand surgery》2013,47(3):343-346
Noma neonatorum should be differentiated from noma, in that it is typically a disease of seriously ill premature infants whose birth weight was low, and is caused by Pseudomonas aerugenosa septicaemia. We know of only two case reports of noma neonatorum involving newborn infants born at full term, so we report here another case of noma neonatorum in a neonate born at full term. In addition we describe the differences between noma neonatorum and noma (cancrum oris), a clinically related entity. 相似文献
88.
89.