全文获取类型
收费全文 | 1577篇 |
免费 | 191篇 |
国内免费 | 20篇 |
专业分类
耳鼻咽喉 | 20篇 |
儿科学 | 59篇 |
妇产科学 | 25篇 |
基础医学 | 114篇 |
口腔科学 | 41篇 |
临床医学 | 225篇 |
内科学 | 308篇 |
皮肤病学 | 104篇 |
神经病学 | 54篇 |
特种医学 | 134篇 |
外科学 | 295篇 |
综合类 | 104篇 |
现状与发展 | 30篇 |
预防医学 | 139篇 |
眼科学 | 15篇 |
药学 | 36篇 |
中国医学 | 3篇 |
肿瘤学 | 82篇 |
出版年
2024年 | 15篇 |
2023年 | 178篇 |
2022年 | 11篇 |
2021年 | 20篇 |
2020年 | 56篇 |
2019年 | 25篇 |
2018年 | 57篇 |
2017年 | 46篇 |
2016年 | 42篇 |
2015年 | 58篇 |
2014年 | 87篇 |
2013年 | 67篇 |
2012年 | 37篇 |
2011年 | 50篇 |
2010年 | 82篇 |
2009年 | 98篇 |
2008年 | 46篇 |
2007年 | 65篇 |
2006年 | 35篇 |
2005年 | 35篇 |
2004年 | 28篇 |
2003年 | 33篇 |
2002年 | 36篇 |
2001年 | 19篇 |
2000年 | 30篇 |
1999年 | 40篇 |
1998年 | 37篇 |
1997年 | 51篇 |
1996年 | 43篇 |
1995年 | 37篇 |
1994年 | 32篇 |
1993年 | 36篇 |
1992年 | 18篇 |
1991年 | 14篇 |
1990年 | 20篇 |
1989年 | 32篇 |
1988年 | 24篇 |
1987年 | 20篇 |
1986年 | 12篇 |
1985年 | 11篇 |
1984年 | 10篇 |
1983年 | 5篇 |
1982年 | 9篇 |
1981年 | 10篇 |
1980年 | 12篇 |
1978年 | 8篇 |
1977年 | 5篇 |
1976年 | 14篇 |
1975年 | 16篇 |
1974年 | 7篇 |
排序方式: 共有1788条查询结果,搜索用时 15 毫秒
1.
A mixed‐method study of effects of a therapeutic play intervention for children on parental anxiety and parents' perceptions of the intervention 下载免费PDF全文
2.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence. 相似文献
3.
4.
5.
6.
7.
Transforming growth factor-beta(1) in the kidney and urine of patients with glomerular disease and proteinuria. 总被引:6,自引:2,他引:4
Dimitrios S Goumenos Sotiris Tsakas Abdel Meguid El Nahas Sotiria Alexandri Simon Oldroyd Pantelitsa Kalliakmani John G Vlachojannis 《Nephrology, dialysis, transplantation》2002,17(12):2145-2152
BACKGROUND: Transforming growth factor-beta(1) (TGF-beta(1)) is the major fibrogenic growth factor implicated in the pathogenesis of renal scarring. Proteinuria is a poor prognostic feature for various types of glomerular disease and its toxic action may be related to the activation of tubular epithelial cells towards increased production of cytokines and chemoattractant peptides. In this work we studied the site of synthesis and expression profile of TGF-beta(1) in the renal tissue of patients with heavy proteinuria and examined the relation of this expression with the urinary excretion of TGF-beta(1). METHODS: Twenty-five patients with heavy proteinuria (8.4+/-3.0 g/24 h) were included in the study. All patients underwent a diagnostic kidney biopsy and were commenced on immunosuppressive therapy with corticosteroids and cyclosporin. The sites of synthesis and expression profile of TGF-beta(1) mRNA and protein in the kidney were examined by in situ hybridization and immunohistochemistry. Urinary and plasma TGF-beta(1) levels were determined by ELISA before the initiation of treatment and 6 months later and compared with those of normal subjects and of patients with IgA nephropathy and normal urinary protein excretion. RESULTS: The site of synthesis and expression of TGF-beta(1) in the renal tissue of patients with heavy proteinuria was mainly localized within the cytoplasm of tubular epithelial cells. Interstitial expression was also present but glomerular TGF-beta(1) expression was found only in patients with mesangial proliferation. Urinary TGF-beta(1) excretion was significantly higher in nephrotic patients compared with normal subjects and with patients with IgA nephropathy and normal urinary protein excretion (783+/-280 vs 310+/-140 and 375+/-90 ng/24 h, respectively; P<0.01). In patients with remission of proteinuria after immunosuppressive therapy, urinary TGF-beta(1) excretion was significantly reduced (from 749+/-290 to 495+/-130 ng/24 h; P<0.01), while in patients with persistent nephrotic syndrome, it remained elevated. CONCLUSIONS: The localization of TGF-beta(1) mRNA and protein within tubular epithelial cells, along with its increased urinary excretion in patients with nephrotic syndrome, suggest the activation of these cells by filtered protein towards increased TGF-beta(1) production. 相似文献
8.
Solitary bronchioloalveolar carcinoma: CT criteria 总被引:14,自引:0,他引:14
Kuhlman JE; Fishman EK; Kuhajda FP; Meziane MM; Khouri NF; Zerhouni EA; Siegelman SS 《Radiology》1988,167(2):379-382
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis. 相似文献
9.
The effect of nutritional status on morbidity after elective surgery for benign gastrointestinal disease 总被引:1,自引:0,他引:1
The effect of nutritional status on the morbidity and mortality of major gastrointestinal surgery for benign disease was studied in 32 patients. Malnutrition was defined as a serum albumin less than 3.5 g/dl and a recent weight loss greater than 10%, in addition to any two of the following: weight for height, midarm circumference or triceps skin-fold thickness less than 10th percentile. The morbidity and mortality in the 17 malnourished patients was 59% and 29%, respectively, compared with 20% and 7% in 15 well-nourished patients matched for age and operative procedure (p less than 0.05). After operation, the mean duration of inadequate oral nutritional intake period (IONIP, defined as a caloric intake greater than 60% requirement) was 11.9 days +/- 2.9 (SEM) in well-nourished patients compared with 30.5 days +/- 3.7 in the malnourished group. The longer IONIP in malnourished patients was a consequence of the higher morbidity in this group, thus warranting the consideration of supportive (postoperative) parenteral nutrition in malnourished patients who undergo major gastrointestinal surgery for benign disease. 相似文献
10.