全文获取类型
收费全文 | 2581篇 |
免费 | 178篇 |
国内免费 | 22篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 66篇 |
妇产科学 | 61篇 |
基础医学 | 453篇 |
口腔科学 | 65篇 |
临床医学 | 153篇 |
内科学 | 532篇 |
皮肤病学 | 36篇 |
神经病学 | 178篇 |
特种医学 | 79篇 |
外科学 | 399篇 |
综合类 | 134篇 |
一般理论 | 1篇 |
预防医学 | 160篇 |
眼科学 | 44篇 |
药学 | 197篇 |
中国医学 | 23篇 |
肿瘤学 | 183篇 |
出版年
2023年 | 25篇 |
2022年 | 52篇 |
2021年 | 75篇 |
2020年 | 39篇 |
2019年 | 69篇 |
2018年 | 58篇 |
2017年 | 52篇 |
2016年 | 75篇 |
2015年 | 102篇 |
2014年 | 175篇 |
2013年 | 162篇 |
2012年 | 210篇 |
2011年 | 228篇 |
2010年 | 136篇 |
2009年 | 115篇 |
2008年 | 144篇 |
2007年 | 142篇 |
2006年 | 138篇 |
2005年 | 103篇 |
2004年 | 94篇 |
2003年 | 96篇 |
2002年 | 70篇 |
2001年 | 53篇 |
2000年 | 38篇 |
1999年 | 52篇 |
1998年 | 18篇 |
1997年 | 15篇 |
1996年 | 17篇 |
1995年 | 13篇 |
1994年 | 14篇 |
1993年 | 5篇 |
1992年 | 25篇 |
1991年 | 22篇 |
1990年 | 13篇 |
1989年 | 17篇 |
1988年 | 13篇 |
1987年 | 12篇 |
1986年 | 12篇 |
1985年 | 12篇 |
1984年 | 11篇 |
1982年 | 5篇 |
1981年 | 4篇 |
1975年 | 5篇 |
1973年 | 4篇 |
1971年 | 3篇 |
1970年 | 3篇 |
1969年 | 3篇 |
1968年 | 5篇 |
1966年 | 4篇 |
1965年 | 3篇 |
排序方式: 共有2781条查询结果,搜索用时 15 毫秒
991.
Weifeng Liu Marilyn M. Bui David Cheong Jamie T. Caracciolo 《Skeletal radiology》2013,42(8):1073-1078
Objective
Hibernoma is a benign neoplasm comprised of brown fat and characteristic hibernoma cells often occurring in adults with proximal extremity/truncal predilection. Limited reports regarding imaging appearance and clinicopathological features of this rare tumor are available. Four histological subtypes have been described. We present nine patients with hibernoma evaluating preoperative imaging findings (eight MRI; one PET, CT), which may distinguish hibernoma from more common benign or low-grade lipomatous neoplasms and attempt to correlate imaging with histological subtype. Clinicopathological data of 14 patients are presented.Materials and methods
Following IRB approval, retrospective review identified 14 patients from our institution between 2000 and 2012. Preoperative imaging, pathology, and medical records were reviewed. We tested the reader’s ability to distinguish hibernoma from lipoma and atypical lipomatous tumor (ALT) at preoperative MRI based on specific imaging criteria. In a separate test, another reader attempted to predict histological subtype. Diagnostic accuracy was recorded.Results
Six men and eight women with a mean age of 53 years were identified. Tumors involved the thigh (4), buttock (3), paraspinal muscles (3), retroperitoneum (2), shoulder (1), and knee (1). Eleven underwent margin negative resection; three excisional biopsy. When asked to differentiate hibernoma from lipoma and ALT, readers correctly identified 80 %, 80 %, and 100 % of hibernomas. Specific histological subtype was accurately predicted in most cases. Mean follow-up was 38 months with no local recurrences or metastases.Conclusions
Hibernomas can be difficult to differentiate from other lipomatous neoplasms, but identification of certain imaging features, common location, and patient demographics can improve preoperative confidence. Given benignity, accurate prospective diagnosis may affect treatment planning and surveillance strategy. 相似文献992.
993.
Treyvaud K Doyle LW Lee KJ Roberts G Cheong JL Inder TE Anderson PJ 《Early human development》2011,87(6):427-431
Background
Examining rates of difficulties in family functioning following very preterm birth has been a relatively neglected area of research.Aims
To examine family functioning, burden and parenting stress in families with very preterm compared with term born children, and investigate influences of parental mental health problems and child neurodevelopmental disability on family outcomes in families with preterm children.Study design
Participants were 184 very preterm and 71 term children and their parents. Parents completed the Family Assessment Device, Parenting Stress Index and Impact on Family questionnaires when their children were 2 years old (corrected for prematurity). Parental mental health and social risk information were also collected. Children were assessed for neurodevelopmental disability.Results
Families with very preterm children reported poorer family functioning (p = .03) compared with families with term born children, with less evidence for differences between families with very preterm and term born children in parenting stress and family burden. Within very preterm families, parental mental health problems were associated with higher levels of parenting stress (p = .001), and parents of children with a neurodevelopmental disability were more likely to report higher family burden (p = .04).Conclusions
For families with very preterm children, parental mental health symptoms and child neurodevelopmental disability may identify families at risk of greater stress and burden who may benefit from additional support. 相似文献994.
Mohammad R. Hojjati Raja Muthupillai James M. Wilson Ourania A. Preventza Benjamin Y. C. Cheong 《The international journal of cardiovascular imaging》2014,30(5):949-957
Vasodilator first-pass stress cardiac magnetic resonance perfusion imaging [stress cardiac magnetic resonance (CMR)] is a reliable, noninvasive method for evaluating myocardial ischemia; however, it does not routinely evaluate metrics such as wall-motion abnormality (WMA) and transient ischemic dilation (TID). Using the new selective A2A adenosine receptor agonist regadenoson, we tested a novel protocol for assessing perfusion defects, WMA, and TID in a single stress CMR session. We evaluated 29 consecutive patients who presented for clinically indicated regadenoson stress CMR. Immediately before and after the regadenoson stress perfusion sequence, we obtained baseline and post-stress cine images in the short-axis orientation to detect worsening or newly developed WMAs. This approach also allowed evaluation of TID. Delayed-enhancement imaging was performed in the standard orientations. All patients tolerated the procedure well. Thirteen patients (45 %) had perfusion abnormalities, and four patients developed TID. Seven patients had WMAs, and three of them also had TID. Patients with TID ± WMAs had multivessel disease documented by coronary angiography. By using regadenoson to assess myocardial ischemia during stress CMR, perfusion defects, WMAs, and TID can be evaluated in a single imaging session. To our knowledge, we are the first to describe this novel approach in a vasodilator stress CMR study. 相似文献
995.
996.
Dae-Won Kim You-Jin Kim Sung Han Park Mi-Ran Yun Jeong-Sun Yang Hae Ji Kang Young Woo Han Han Saem Lee Heui Man Kim Hak Kim A-Reum Kim Deok Rim Heo Su Jin Kim Jun Ho Jeon Deokbum Park Joo Ae Kim Hyang-Min Cheong Jeong-Gu Nam Kisoon Kim Sung Soon Kim 《Emerging infectious diseases》2016,22(1):100-104
An outbreak of nosocomial infections with Middle East respiratory syndrome coronavirus occurred in South Korea in May 2015. Spike glycoprotein genes of virus strains from South Korea were closely related to those of strains from Riyadh, Saudi Arabia. However, virus strains from South Korea showed strain-specific variations. 相似文献
997.
Park SH Kim GH Park do Y Shin NR Cheong JH Moon JY Lee BE Song GA Seo HI Jeon TY 《Journal of gastroenterology and hepatology》2011,26(9):1441-1446
Background and Aim: Ectopic pancreas is a common submucosal lesion in the stomach, but its histological diagnosis is usually difficult when tissue samples are obtained with a conventional biopsy forceps. The aim of this study was to describe the endosonographic features of gastric ectopic pancreas. Methods: We retrospectively analyzed a database of all patients who underwent endoscopic ultrasonography (EUS) at Pusan National University Hospital from July 2006 to August 2010. A total of 26 patients with histologically confirmed ectopic pancreas were included in the study. The EUS features of their lesions were analyzed. Results: Ten lesions were located in the antrum, and 16 lesions were located in the body. Nine lesions (34.6%) showed an umbilication or central dimpling on the surface, and a mural growth pattern was most commonly observed (61.5%). Twenty‐four lesions (92.3%) showed hypoechoic echogenicity, and 13 lesions (50.0%) were heterogeneous. The borders were indistinct in 16 lesions (61.5%) and lobulated margins were observed in 16 lesions (61.5%). Anechoic cystic or tubular structures appeared in 17 lesions (65.4%), and 20 lesions (76.9%) involved two or more sonographic layers. Conclusions: The characteristic EUS features of ectopic pancreas are indistinct borders, lobulated margins, presence of anechoic duct‐like structures, a mural growth pattern, and localization within two or more layers. These EUS features are potentially useful for differentiating ectopic pancreas from other mesenchymal tumors in the stomach. 相似文献
998.
Kim SU Jang HW Cheong JY Kim JK Lee MH Kim DJ Yang JM Cho SW Lee KS Choi EH Park YN Han KH 《Journal of gastroenterology and hepatology》2011,26(1):171-178
Aim: We investigated the accuracy of liver stiffness measurement (LSM) in chronic hepatitis C (CHC) in a multicenter, prospective study in South Korea. Methods: Between June 2005 and July 2009, 91 CHC patients without a previous history of antiviral treatment, clinical evidences of cirrhosis, coinfection with other viruses, and heavy alcohol consumption and with alanine aminotransferase (ALT) ≤ 5x upper limit of normal, total bilirubin ≤ 1.5 mg/dL, sufficient liver biopsy quality (≥ 15 mm and more than six portal tracts), interquartile range to median liver stiffness (LS) value ratio ≤ 0.21, and more than 10 valid measurements, were recruited. The Batts and Ludwig scoring system was used for histologic assessment. Age–platelet index (API), aspartate aminotransferase (AST)–to–platelet ratio index (APRI), and age–spleen–platelet ratio index (ASPRI) were calculated. Area under the receiver operating characteristic curve (AUROC) was used to evaluate the performance of LSM and other noninvasive models. Results: The mean age was 47.9 years, and the mean LS value was 7.7 kPa (44 men and 47 women). LS value was highly correlated to the fibrosis stages (r = 0.835, P < 0.001). The AUROCs of LSM were 0.909 for ≥ F2, 0.993 for ≥ F3, and 0.970 for F = 4 and were superior to those of API (0.72, 0.858, and 0.948, respectively), APRI (0.780, 0.887, and 0.904, respectively), and ASPRI (0.713, 0.862, and 0.957, respectively). The optimal cutoff LS values were 6.2 kPa for ≥ F2, 7.7 kPa for ≥ F3, and 11.0 kPa for F = 4. Conclusions: Our data suggest that LSM can accurately assess liver fibrosis in patients with CHC and be applied in South Korea. 相似文献
999.
Park SH Kim CH Kim DJ Cheong JY Cho SW Hwang SG Lee YJ Cho M Yang JM Kim YB 《Digestive diseases and sciences》2011,56(6):1828-1834
Background/Aims
Treating a group of chronic hepatitis B virus (HBV)-infected patients with high viral load and advanced fibrosis or cirrhosis, regardless of their serum alanine aminotransferase (ALT) levels, is recommended. The aim of this study was to derive and validate a model to predict advanced fibrosis in a cohort of patients with viral replication and normal or minimally raised ALT [ALT < 2 × upper normal limit (UNL)].Methods
Information was collected from 124 patients who underwent liver biopsy. The diagnostic value of predictors was judged using multivariate logistic modeling and area under the receiver operating characteristic curves (ROC area).Results
Advanced fibrosis (F3 or F4 on METAVIR scoring schema) was diagnosed in 45.7% (95% CI, 34?C57.4%) of the patients of the derivation set (70 patients) and in 37% (95% CI, 24.2?C49.9%) of the validation set (54 patients). In the derivation set, age and aspartate aminotransferase (AST) were independent clinical predictors of advanced fibrosis. The ROC areas of this Age?CAST model were 0.8 (95% CI, 0.7?C0.9) in the derivation set and 0.82 (95% CI, 0.71?C0.93) in the validation set, respectively. Without missing a single case, this model identified 11 patients (20%) without advanced fibrosis in the validation set.Conclusions
A substantial proportion of patients with high viral load and ALT < 2 × UNL have advanced fibrosis. A simple model including age and AST is an easily applicable tool for physicians to guide their decisions on whether or not to perform liver biopsy in individual patients. 相似文献1000.
Suitability rate of endovascular aneurysm repair (EVAR) and the anatomic features causing unsuitability have not been well determined in Asian patients who have abdominal aortic aneurysm (AAA). In a single Korean center, a total of 191 patients with abdominal aortic aneurysm (maximal diameter ≥ 4 cm) were identified. Aortoiliac morphologic characteristics in contrast-enhanced computed tomography images were retrospectively reviewed to determine suitability for EVAR with four FDA-approved stent-grafts. AAA was considered ideally suitable for EVAR in 46.6% of patients. The most frequent causes for unsuitability were common iliac artery (CIA) aneurysm (61.8%) and excessive neck angulation (52.9%). Problems such as small and/or short neck and small access were found in minor incidences. If CIA aneurysm is dealt by overstenting with sacrifice of internal iliac artery, suitability rate can increase to 65%. Larger aneurysms were more frequently unsuitable for EVAR and had more chance of having multiple unfavorable features. In conclusion, the overall feasibility rate for EVAR in Korean patients was not different from that in Western patients. However, considering the difference in the major causes of unsuitability, more attention has to be paid to neck angulation and CIA aneurysm to provide EVAR for more Korean patients especially who have large aneurysm. 相似文献