全文获取类型
收费全文 | 3731篇 |
免费 | 235篇 |
国内免费 | 23篇 |
专业分类
耳鼻咽喉 | 27篇 |
儿科学 | 116篇 |
妇产科学 | 63篇 |
基础医学 | 481篇 |
口腔科学 | 106篇 |
临床医学 | 265篇 |
内科学 | 899篇 |
皮肤病学 | 51篇 |
神经病学 | 293篇 |
特种医学 | 111篇 |
外科学 | 673篇 |
综合类 | 19篇 |
预防医学 | 309篇 |
眼科学 | 56篇 |
药学 | 201篇 |
中国医学 | 25篇 |
肿瘤学 | 294篇 |
出版年
2023年 | 28篇 |
2022年 | 69篇 |
2021年 | 126篇 |
2020年 | 77篇 |
2019年 | 111篇 |
2018年 | 132篇 |
2017年 | 72篇 |
2016年 | 86篇 |
2015年 | 115篇 |
2014年 | 134篇 |
2013年 | 169篇 |
2012年 | 308篇 |
2011年 | 288篇 |
2010年 | 176篇 |
2009年 | 130篇 |
2008年 | 247篇 |
2007年 | 270篇 |
2006年 | 242篇 |
2005年 | 211篇 |
2004年 | 196篇 |
2003年 | 234篇 |
2002年 | 214篇 |
2001年 | 30篇 |
2000年 | 15篇 |
1999年 | 25篇 |
1998年 | 27篇 |
1997年 | 18篇 |
1996年 | 22篇 |
1995年 | 14篇 |
1994年 | 15篇 |
1993年 | 15篇 |
1992年 | 18篇 |
1991年 | 11篇 |
1990年 | 14篇 |
1989年 | 13篇 |
1988年 | 13篇 |
1987年 | 7篇 |
1986年 | 14篇 |
1985年 | 6篇 |
1984年 | 10篇 |
1983年 | 3篇 |
1982年 | 14篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1978年 | 7篇 |
1976年 | 3篇 |
1975年 | 3篇 |
1964年 | 2篇 |
1932年 | 2篇 |
1929年 | 2篇 |
排序方式: 共有3989条查询结果,搜索用时 0 毫秒
71.
BACKGROUND: Previous studies have shown that mechanical and electronic intracardiac echocardiography (ICE) improves ultrasound monitoring during transcatheter patent foramen ovale (PFO) interventional closure. OBJECTIVES: This study sought to compare the procedural data, clinical imaging quality, and effectiveness PFO closure by using two different ICE monitoring modalities. METHODS: Patients referred for PFO closure (n = 82) were randomly assigned to mechanical (group 1) or electronic (group 2) ICE monitoring of Amplatzer device implantation. The digital ICE images were evaluated offline by means of absolute visual grading analysis score (VGAS(abs)), and the residual shunting at follow-up were assessed by means of contrast echocardiographic studies, all blinded regarding the ICE closure monitoring modality. RESULTS: The two groups were comparable with respect to clinical baseline characteristics, intracardiac fossa ovalis measurements, and procedural data (fluoroscopy time, procedure time and measurement of the amount of radiation that the patients absorbed). The total VGAS(abs) ranked the mechanical clinical images in a higher order than the electronic ones (3.78 +/- 0.09 vs 3.58 +/- 0.12, P = 0.005); additionally, three patients (7.3%) of group 2 needed to cross over to mechanical ICE monitoring because a right-convex atrial septal aneurysm configured itself incompletely. No differences in rates of residual shunting were observed at 12 months follow-up between the two groups (97.5% vs 94.7%, P = 0.951). CONCLUSIONS: Electronic monitoring of PFO closure performed a less diagnostic impact than the mechanical one while maintaining comparable procedural data and clinical outcome. These results represent an important step in validating these new intracardiac ultrasound imaging modalities. 相似文献
72.
Laryngeal electromyography and prognosis of unilateral vocal fold paralysis—A long‐term prospective study
下载免费PDF全文
![点击此处可从《The Laryngoscope》网站下载免费的PDF全文](/ch/ext_images/free.gif)
73.
C-reactive protein levels and survival in patients with moderate to very severe COPD 总被引:1,自引:0,他引:1
de Torres JP Pinto-Plata V Casanova C Mullerova H Córdoba-Lanús E Muros de Fuentes M Aguirre-Jaime A Celli BR 《Chest》2008,133(6):1336-1343
BACKGROUND: Serum levels of C-reactive protein (CRP) are increased in patients with COPD and correlate modestly with variables predictive of outcomes. In epidemiologic studies, CRP level is associated with all-cause mortality in patients with mild-to-moderate disease. OBJECTIVE: To determine if CRP levels are associated with survival in patients with moderate to very severe COPD in comparison with other well-known prognostic parameters of the disease. METHODS: In 218 stable patients with COPD, we measured baseline serum CRP level, BODE (body mass index, obstruction, dyspnea, and exercise capacity) index and its components, arterial oxygenation (Pao(2)), inspiratory capacity (IC) to total lung capacity (TLC) ratio, and Charlson comorbidity score. We followed up the patients over time and evaluated the strength of the association between the variables and all-cause mortality. RESULTS: During the follow-up time (median, 36 months; 25th to 75th percentiles, 24 to 50 months), 54 patients (25%) died. CRP levels were similar between survivors and the deceased (median, 3.8 mg/L; 95% confidence interval, 1.9 to 8.1; vs median, 4.5 mg/L; 95% confidence interval, 2.1 to 11.5; p = 0.22) and was not significantly associated with survival. CONCLUSIONS: In this population of patients with clinically moderate to very severe COPD, the level of CRP level was not associated with survival compared with other prognostic clinical tools such as the BODE index, modified Medical Research Council scale, 6-min walk distance, percentage of predicted FEV(1), IC/TLC ratio < 0.25, and Pao(2). Other long-term studies of well-characterized patients with COPD could help determine the exact role of CRP levels as a biomarker in patients with clinical COPD. 相似文献
74.
75.
Benefits of radial distortion correction in arthroscopic surgery: a first experimental study on a knee model
下载免费PDF全文
![点击此处可从《The international journal of medical robotics + computer assisted surgery : MRCAS》网站下载免费的PDF全文](/ch/ext_images/free.gif)
76.
Winck JC Vitacca M Morais A Barbano L Porta R Teixeira-Pinto A Ambrosino N 《Chest》2004,126(2):382-388
STUDY OBJECTIVES: To compare the tolerance and physiologic effects of a 5-night treatment with either nasal proportional assist ventilation (PAV) or pressure support ventilation (PSV) in patients with chronic ventilatory failure. DESIGN: Cross-over, randomized, controlled study. SETTING: Rehabilitation units of pneumology department. PATIENTS OR PARTICIPANTS: Four patients with COPD and 10 patients with restrictive thoracic diseases with chronic hypercapnia (median baseline Paco(2), 55.1 mm Hg) were studied. INTERVENTIONS: In a cross-over study, nasal PAV and PSV set at the patient's comfort were randomly applied during 5 consecutive nights (with a 2-night washout period). MEASUREMENTS AND RESULTS: Continuous nocturnal pulse oximetric saturation (Spo(2)) and arterial blood gas results at wake-up were evaluated at baseline during spontaneous breathing and on the fifth day of ventilatory support. Dyspnea, sleep quality, adaptation, and comfort at inspiration and expiration by visual analog scale (VAS) were evaluated every day as well as a side effects score. On the fifth day, there were no significant differences in daytime Paco(2) (median PAV, 53.3 mm Hg; median PSV, 50.2; p = 0.168). Mean nocturnal Spo(2) improved significantly with both PAV and PSV without any significant differences between modes (baseline median, 92%; PAV median, 94.5%; PSV median, 95%). The percentage of the study night spent < 90% Spo(2) (T90) was slightly but significantly higher with PAV than with PSV (median PAV T90, 4%; median PSV T90, 2%; p = 0.049). The VAS symptom score was similar at day 5 between modes; however, nasal and oral dryness were lower (p = 0.05) and alarm noise was higher (p = 0.037) with PAV. CONCLUSIONS: After 5 days of treatment, both modes had similar tolerance, and were equally effective in reducing daytime hypercapnia and improving nocturnal saturation and symptoms. However, PAV induced less nasal and oral dryness but was associated with higher alarm noise. 相似文献
77.
78.
The objective was to estimate the prevalence of plasma aldosterone concentration:plasma renin activity ratio >30 ng/dL:ng/mL/h in patients with resistant hypertension and to describe the computed tomography findings of adrenal glands in those with elevated ratios. In a cross-sectional design, 492 patients were enrolled. All patients with plasma aldosterone concentration:plasma renin activity ratio >or=30 ng/dL:ng/mL/h (n=77) underwent abdominal computed tomography. Patients with an adrenal image of possible aldosterone-producing adenoma underwent a saline-loading test. The prevalence of elevated plasma aldosterone concentration:plasma renin activity ratio was 15.7% (95% confidence interval, 12.6-19.2). Twelve patients showed adrenal abnormalities on computed tomography. The level of renin was low in 50% of the sample. Results indicate a low prevalence of aldosterone-producing adenoma. Our evidence points out the importance of confirming the hypothesis that essential hypertension, low-renin hypertension, and idiopathic hyperaldosteronism could be the same disease, but at different neurohormonal stages, and aldosterone-producing adenoma may be yet another disease. 相似文献
79.
Jose F. Camargo Jacques Simkins Thiago Beduschi Akin Tekin Laura Aragon Armando Pérez-Cardona Clara E. Prado Michele I. Morris Lilian M. Abbo Rafael Cantón 《Antimicrobial agents and chemotherapy》2015,59(10):5903-5908
New antibiotic options are urgently needed for the treatment of carbapenem-resistant Enterobacteriaceae infections. We report a 64-year-old female with prolonged hospitalization following an intestinal transplant who developed refractory bacteremia due to a serine carbapenemase-producing pandrug-resistant isolate of Klebsiella pneumoniae. After failing multiple antimicrobial regimens, the patient was successfully treated. 相似文献
80.
All‐on‐4® Treatment Concept for the Rehabilitation of the Completely Edentulous Mandible: A 7‐Year Clinical and 5‐Year Radiographic Retrospective Case Series with Risk Assessment for Implant Failure and Marginal Bone Level
下载免费PDF全文
![点击此处可从《Clinical implant dentistry and related research》网站下载免费的PDF全文](/ch/ext_images/free.gif)