全文获取类型
收费全文 | 1568篇 |
免费 | 116篇 |
国内免费 | 25篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 147篇 |
妇产科学 | 14篇 |
基础医学 | 152篇 |
口腔科学 | 67篇 |
临床医学 | 152篇 |
内科学 | 351篇 |
皮肤病学 | 38篇 |
神经病学 | 31篇 |
特种医学 | 328篇 |
外科学 | 85篇 |
综合类 | 22篇 |
一般理论 | 2篇 |
预防医学 | 87篇 |
眼科学 | 16篇 |
药学 | 90篇 |
1篇 | |
中国医学 | 2篇 |
肿瘤学 | 120篇 |
出版年
2023年 | 8篇 |
2022年 | 5篇 |
2021年 | 24篇 |
2020年 | 11篇 |
2019年 | 21篇 |
2018年 | 29篇 |
2017年 | 22篇 |
2016年 | 28篇 |
2015年 | 36篇 |
2014年 | 32篇 |
2013年 | 54篇 |
2012年 | 18篇 |
2011年 | 15篇 |
2010年 | 44篇 |
2009年 | 83篇 |
2008年 | 24篇 |
2007年 | 43篇 |
2006年 | 39篇 |
2005年 | 36篇 |
2004年 | 20篇 |
2003年 | 27篇 |
2002年 | 24篇 |
2001年 | 23篇 |
2000年 | 21篇 |
1999年 | 31篇 |
1998年 | 101篇 |
1997年 | 118篇 |
1996年 | 112篇 |
1995年 | 77篇 |
1994年 | 83篇 |
1993年 | 98篇 |
1992年 | 17篇 |
1991年 | 17篇 |
1990年 | 19篇 |
1989年 | 44篇 |
1988年 | 42篇 |
1987年 | 26篇 |
1986年 | 33篇 |
1985年 | 31篇 |
1984年 | 17篇 |
1983年 | 15篇 |
1982年 | 19篇 |
1981年 | 34篇 |
1980年 | 21篇 |
1979年 | 8篇 |
1978年 | 8篇 |
1977年 | 21篇 |
1976年 | 19篇 |
1975年 | 7篇 |
1970年 | 2篇 |
排序方式: 共有1709条查询结果,搜索用时 15 毫秒
101.
The breast is a complex anatomical structure where achieving a homogeneous dose distribution with radiation treatment is difficult. Despite obvious similarities in the approach to such treatment (using tangents) there is variation in the process of simulation, planning and treatment between radiation oncologists. Previous Australasian studies in the treatment of lung cancer, prostate cancer and Hodgkin’s disease highlighted considerable variation in many areas of treatment. As part of a multicentre breast phantom study involving 10 radiation oncology departments throughout New South Wales (NSW) and the Australian Capital Territory (ACT), a 22-question survey was distributed. The aim of the survey was to assess the extent of variation in the approach to the simulation, planning and treatment of early breast cancer using tangents. Responses from 10 different radiation oncology departments revealed variation in most areas of the survey. There is no reason to assume similar variations do not occur Australasia wide. Studies involving overseas radiation oncologists also reveal a wide variation in treating early breast cancer. The consequences of such variations remain unclear. 相似文献
102.
A patient with progressive osteolysis of the carpal and tarsal bones with glomerulonephritis of unusual severity is described. There was a notable absence of osteodystrophy in this and other reported cases who had chronic renal failure. 相似文献
103.
Pneumocystis carinii pneumonia studied by gallium-67 scanning 总被引:1,自引:0,他引:1
The validity and reliability of gallium-67 (Ga-67) scanning for diagnosis and follow-up of Pneumocystis carinii pneumonia (PCP) were assessed in 34 patients thought to have pulmonary complications of acquired immunodeficiency syndrome (AIDS). Overall sensitivity was 94% and specificity 74%. Among patients with normal or equivocal chest radiographs at the time of admission, sensitivity was 86% and specificity 85%. The authors consider Ga-67 scanning a valid and reliable adjunct in the diagnosis of PCP in AIDS patients with respiratory symptoms when the chest radiograph is normal or equivocal. 相似文献
104.
Fifty-nine pediatric patients with urinary tract infection (UTI) underwent renal ultrasonography, excretory urography, and voiding cystourethrography. The imaging procedures were analyzed retrospectively to determine their relative effectiveness in detecting abnormalities that might predispose the patient to UTI. Voiding cystourethrography provided valuable information, particularly the presence or absence of vesicoureteral reflux, that could not be obtained from the other procedures. Excretory urography was less specific than ultrasonography in the majority of patients, with the exception of those who had renal scarring. The authors recommended ultrasonography as the initial imaging procedure in the evaluation of children with UTI. When the sonogram is normal, excretory urography is not considered necessary, but voiding cystourethrography is thought to be essential. If sonography is abnormal, excretory urography and/or other follow-up studies are indicated. 相似文献
105.
F Fabrizi P Martin V Dixit M Brezina MJ Cole S Gerosa M Mousa G Gitnick 《American journal of kidney diseases》1998,31(4):647-654
Serological data indicate that hepatitis C virus (HCV) infection is very common among chronic hemodialysis (HD) patients. Circumstantial evidence suggests that hemodialysis per se is an important risk factor for this infection. We used a novel methodology, the branched DNA (bDNA) signal amplification assay, which is capable of detecting HCV RNA and of quantifying HCV viral load in serum, to prospectively determine the rate of acquisition of HCV infection in 274 anti-HCV-negative patients undergoing HD treatment in four hemodialysis units. Moreover, we used bDNA testing to analyze the dynamics of HCV acquisition among HD patients, a high-risk group for HCV infection with immune compromise conferred from uremia. Two patients were identified with de novo acquisition during 1 year of prospective bDNA testing. Thus, the HCV incidence was 0.73% per year. De novo acquisition of HCV infection was observed in the absence of identifiable parenteral risk factors. Both patients showed the same pattern of HCV acquisition: they underwent an initial viremic phase that was associated with an increase in alanine transaminase (ALT) activity and that preceded the anti-HCV seroconversion. This was followed by HCV RNA clearance and normalization of ALT activity. Anti-HCV positivity occurred 1 and 2 months after the ALT increase in the first and second patients, respectively. Although HCV incidence was low (0.73%), further research is warranted to set the optimal policy for eliminating the risk of nosocomial transmission of HCV in the HD setting. Our findings show the pattern of HCV acquisition in chronic HD patients and emphasize the need to screen the HD population for ALT measurement combined with anti-HCV testing for detecting hepatitis C. HCV RNA testing can identify HCV before seroconversion in individuals with deranged liver function tests. The acquisition of HCV in HD patients without identifiable risk is confirmed. 相似文献
106.
107.
108.
109.
110.
B Hitze A Bosy‐Westphal S Plachta‐Danielzik F Bielfeldt M Hermanussen MJ Müller 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(2):256-262
Aim: This study investigates the effect of rapid weight gain in term children, adolescents and young adults born appropriate for gestational age. Methods: In all, 173 girls and 178 boys aged 6.1–19.9 (12.5 ± 3.1)years participated. Rapid weight gain (group 1) was defined as a change in weight‐SDS (standard deviation score) from birth till two years >0.67, ‘no change’ as ≥?0.67 and ≤0.67 (group 2) vs ‘slow weight gain’ as 0.67 (group 3). BMI‐SDS, waist circumference (WC) z‐score, fat mass (FM)/fat free mass (FFM; Air‐Displacement‐Plethysmography), resting energy expenditure (REE; ventilated hood system), cardio‐metabolic risk factors, serum leptin and adiponectin were assessed. >90th age‐/sex‐specific BMI‐percentile was defined as overweight. Parental BMI, socio‐economic status and lifestyle were assessed as confounders. Results: A total of 22.8% gained weight rapidly, and 15.7% was overweight. Group 1 compared with group 2 and 3 subjects was taller, heavier and had a higher prevalence of overweight (girls/boys: 26.2%/28.9% vs 11.6%/19.0% vs 2.8%/5.0%; p < 0.01/p < 0.05). Concomitantly, a higher WC, %FM and FFM were observed. Rapid weight gain was positively associated with REE (adjusted for FFM) in boys (r = 0.26; p < 0.01), but not with cardio‐metabolic risk factors. Conclusion: Rapid weight gain was related to increases in height, weight, a higher prevalence of overweight and central fat distribution. In addition, rapid weight gain was related to a higher REE in boys, but not to cardio‐metabolic risk factors. 相似文献