全文获取类型
收费全文 | 2051篇 |
免费 | 90篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 29篇 |
儿科学 | 131篇 |
妇产科学 | 84篇 |
基础医学 | 215篇 |
口腔科学 | 184篇 |
临床医学 | 195篇 |
内科学 | 340篇 |
皮肤病学 | 27篇 |
神经病学 | 139篇 |
特种医学 | 68篇 |
外科学 | 327篇 |
综合类 | 28篇 |
一般理论 | 3篇 |
预防医学 | 155篇 |
眼科学 | 47篇 |
药学 | 106篇 |
中国医学 | 3篇 |
肿瘤学 | 71篇 |
出版年
2024年 | 1篇 |
2023年 | 8篇 |
2022年 | 18篇 |
2021年 | 62篇 |
2020年 | 39篇 |
2019年 | 53篇 |
2018年 | 57篇 |
2017年 | 33篇 |
2016年 | 85篇 |
2015年 | 73篇 |
2014年 | 93篇 |
2013年 | 114篇 |
2012年 | 168篇 |
2011年 | 146篇 |
2010年 | 102篇 |
2009年 | 70篇 |
2008年 | 125篇 |
2007年 | 122篇 |
2006年 | 119篇 |
2005年 | 146篇 |
2004年 | 111篇 |
2003年 | 77篇 |
2002年 | 89篇 |
2001年 | 48篇 |
2000年 | 35篇 |
1999年 | 33篇 |
1998年 | 16篇 |
1997年 | 19篇 |
1996年 | 6篇 |
1995年 | 4篇 |
1994年 | 9篇 |
1993年 | 4篇 |
1992年 | 4篇 |
1991年 | 11篇 |
1990年 | 7篇 |
1989年 | 8篇 |
1988年 | 7篇 |
1987年 | 7篇 |
1986年 | 9篇 |
1985年 | 4篇 |
1984年 | 3篇 |
1981年 | 2篇 |
1976年 | 2篇 |
1975年 | 1篇 |
1972年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有2152条查询结果,搜索用时 15 毫秒
1.
Alper Kurtoglu Alauddin Kochai Mustafa Erkan Inanmaz Erhan Sukur Dogan Keskin Mehmet Türker Mustafa Uysal Zafer Sen Ismail Daldal 《Medicine》2021,100(13)
Different methods have been used throughout the years for syndesmotic injury but there is no consensus on the ideal treatment. Some methods are expensive and some have more complications. The aim of this study is to compare single suture endobutton with double suture endobutton and screw fixation for syndesmotic injury.Sixty nine patients with syndesmotic injury with fibular fractures whom were treated with a single interosseous suture endobutton system (ZipTightTM, Zimmer Biomet), a double interosseous suture endobutton system (ZipTightTM, Zimmer Biomet) and 1 syndesmotic screw (TST, Istanbul, Turkey) were included in this study. Functional and radiological results from patient records between 2015 and 2018 were retrospectively evaluated.Twenty patients were treated with the double interosseous suture endobutton, 23 were treated with the single interosseous suture endobutton, and 26 were treated with traditional AO screw fixation. Three patients from the screw fixation group (11.5%) required revision surgery (P < .05). All the radiologic and clinical outcomes were statistical similar in all 3 groups.Our findings showed that the interosseous suture endobutton system is at least as safe as the screw fixation technique for treatment of syndesmosis joint injuries and can be used as an alternative to the screw method. The interosseous suture endobutton system eliminates the need for a second surgery to remove the hardware, which minimizes the probability of re-diastasis. Since our results showed no statistical difference between single and double interosseous suture endobutton systems, the less costly single endobutton system may be the better alternative. 相似文献
2.
Irmak Karaca Suzan Güven Yılmaz Melis Palamar Halil Ateş 《Ocular immunology and inflammation》2020,28(6):947-951
ABSTRACT
Purpose
To investigate the effect of 1% tropicamide on anterior chamber aqueous flare (ACAF) measurements acquired with laser flare meter in patients with pseudoexfoliation. 相似文献3.
OBJECTIVE: To evaluate the possible effects of sex and age on strength-duration time constant (SDTC). METHODS: The SDTC of 126 healthy volunteers was measured following stimulation of right median nerve at the wrist. Variations in values were evaluated according to sex and age. RESULTS: The SDTC was 438.6+/-114.5 micros in women and 396.2+/-90.3 in men (P=.023). In men, as age increased, so did SDTC. However, this was not true in women. Comparing the values of women and men, aged below 40, demonstrated a difference in excitability, confined to younger patients. CONCLUSIONS: As SDTC depends on the biophysical properties of the axonal membrane and can provide some information about Na(+) channel function, these data raise the possibility of a difference in Na(+) channel function between men and women and a difference in the conductance with age. SIGNIFICANCE: The age- and sex-related differences shown in this study suggest a possible biochemical or hormonal influence on axonal excitability. 相似文献
4.
5.
E Y S?zmen Z Kerry F Uysal G Yetik M Yasa L Ustünes T Onat 《Clinical chemistry and laboratory medicine》2000,38(1):21-25
There is a large body of literature describing the causative role of oxidative stress mediated by increased levels of reactive oxygen species in the pathogenesis of cardiovascular disease such as atherosclerosis, hypertension, and restenosis after angioplasty. The positioning of a soft silicone collar around the rabbit carotid artery elicits intimal thickening. The findings from recent studies demonstrated that both intimal thickening and atherosclerosis lead to synthesis of inducible nitric oxide synthase, resulting in abundant amounts of nitric oxide. We investigated the effects of collaring and nicardipine treatment on the activities of antioxidant enzymes, superoxide dismutase and catalase, and total nitrite/nitrate levels, stable products of nitric oxide. Placing the collar increased the total nitrite/ nitrate levels and decreased superoxide dismutase activity in collared arteries. Treatment with nicardipine (20 mg/kg/day, s.c.) prevented enhanced nitric oxide degradation without affecting superoxide dismutase and catalase activities. Our results suggest that enhanced nitric oxide production and superoxide anion are generated in response to the collaring, resulting in oxidative stress within the segment in this model. 相似文献
6.
OBJECTIVE: Hyperventilation and ischaemia increase axonal excitability by changing Na+ conductance in healthy subjects. However, the changes in excitability during and after ischaemia in diabetic patients are less than in healthy controls. This is known as ischaemic resistance. In this study, we investigated the effects of hyperventilation for 20 min on strength-duration time constant (SDTC) of motor axons of the median nerve of diabetic patients with polyneuropathy to determine whether diabetics are less affected by hyperventilation, a form of resistance similar to the ischaemic resistance of diabetics. METHODS: The SDTC of 14 diabetic patients with polyneuropathy and 10 healthy volunteers were measured following stimulation of right median nerve at the wrist prior to and after hyperventilation for 20 min. RESULTS: There was a significant increase in the SDTC in control subjects, but no significant change in the SDTC for patients with diabetic polyneuropathy. The score of the clinical response (paraesthesiae and carpopedal spasm) to hyperventilation of controls was also significantly greater in the controls than the patients. CONCLUSION: Hyperventilation for 20 min has little influence on SDTC in patients with diabetic polyneuropathy. SIGNIFICANCE: The 'resistance' of diabetic nerve is not confined to ischaemia but involves other manoeuvres that can alter axonal excitability. 相似文献
7.
David L Reich Loren M Horn Sabera Hossain Suzan Uysal 《European journal of cardio-thoracic surgery》2004,25(3):401-6; discussion 406-8
OBJECTIVES: Deep hypothermic circulatory arrest (DHCA) is commonly used during thoracic aortic surgery, and is initiated only after a sufficient degree of cerebral hypothermia is induced. The criteria for initiating DHCA vary among institutions: most centers use temperature criteria, some use electroencephalography, and a minority use jugular bulb oxyhemoglobin saturation SjO(2) criteria. The purpose of this study was to determine whether the use of SjO(2) monitoring to guide the onset of DHCA was associated with better post-operative neuropsychological outcome. METHODS: Sixty-one thoracic aortic surgical patients underwent both pre- and post-operative neuropsychological testing. Patients were divided into three groups: (1) those with SjO(2)> or =95% at DHCA onset; (2) those with SjO(2)<95% at DHCA onset; and (3) those without SjO(2) monitoring. RESULTS: There were no statistically significant differences in the incidence of post-operative decline in neuropsychological function among the three groups of patients. Patients in whom SjO(2) data were used to guide onset of DHCA had lower esophageal and bladder temperatures at that time compared with patients without SjO(2) monitoring. CONCLUSIONS: Monitoring of SjO(2) had no apparent effect upon post-operative neuropsychological outcome, and there were no trends in our small patient cohort suggesting differences that our study was not adequately powered to detect. Use of SjO(2) monitoring was associated with more profound hypothermia prior to DHCA due to more prolonged cooling in attempts to bring the SjO(2) above the 95% threshold. Using our institutional cooling protocol, SjO(2) monitoring does not appear to increase neuroprotection in patients undergoing DHCA for thoracic aortic repairs. 相似文献
8.
9.
10.
Abdou Elhendy Marcel L. Geleijnse Ron T. van Domburg Jeroen J. Bax Peter R. Nierop Suzan A. M. Beerens Roelf Valkema Eric P. Krenning M. Mohsen Ibrahim Jos R. T. C. Roelandt 《European journal of nuclear medicine and molecular imaging》1997,25(1):69-78
Stress echocardiography has been considered an accurate method for the diagnosis of coronary artery disease in hypertensive
patients and in patients with left ventricular hypertrophy. In contrast, the specificity of myocardial perfusion scintigraphy
in these patients has been questioned. The aim of this study was to compare the accuracy of these two imaging modalities in
conjunction with dobutamine stress test for the diagnosis of coronary artery disease in hypertensive patients with and without
left ventricular hypertrophy. Dobutamine (up to 40 μg kg–1min–1) stress echocardiography in conjunction with sestamibi (MIBI) single-photon emission tomography (SPET) was performed in 84
patients with the diagnosis of systemic hypertension who had been referred for evaluation of myocardial ischaemia. Ischaemia
was defined as new or worsened wall motion abnormalities at echocardiography and reversible perfusion defects at SPET. Significant
coronary artery disease (≥50% luminal diameter stenosis) was detected in 66 patients (79%). The sensitivity, specificity and
accuracy of the ischaemic pattern at echocardiography for the diagnosis of coronary artery disease were 73% (CI 63%–82%),
83% (CI 75%–91%) and 75% (CI 66%–84%), those for MIBI were 67% (CI 57%–77%), 83% (CI 75%–91%) and 70% (CI 60%–80%) respectively
(P = NS vs echocardiography). Significant stenosis was detected in 123 (49%) of the 252 analysed coronary arteries. The sensitivity,
specificity and accuracy of echocardiography for the regional diagnosis of coronary artery disease were 63% (CI 56%–69%),
90% (CI 86%–94%) and 77% (CI 72%–82%). Those for MIBI were 58% (CI 51%–64%), 91% (CI 87%–94%) and 75% (CI 69%–80) respectively
(P = NS vs echocardiography). Left ventricular hypertrophy was detected in 59 patients (70%) by echocardiography and did not
influence the overall or regional specificity of echocardiography or MIBI SPET. It is concluded that in hypertensive patients,
dobutamine stress echocardiography and MIBI SPET have a comparable accuracy for the overall and regional diagnosis of coronary
artery disease. Hypertensive patients with or without left ventricular hypertrophy should not be considered unsuitable candidates
for stress myocardial perfusion scintigraphy.
Received 10 July and in revised form 19 September 1997 相似文献