首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1747篇
  免费   101篇
  国内免费   16篇
耳鼻咽喉   23篇
儿科学   159篇
妇产科学   33篇
基础医学   154篇
口腔科学   69篇
临床医学   123篇
内科学   413篇
皮肤病学   33篇
神经病学   103篇
特种医学   61篇
外科学   304篇
综合类   29篇
预防医学   54篇
眼科学   24篇
药学   143篇
中国医学   10篇
肿瘤学   129篇
  2023年   17篇
  2022年   31篇
  2021年   63篇
  2020年   37篇
  2019年   60篇
  2018年   66篇
  2017年   53篇
  2016年   57篇
  2015年   54篇
  2014年   77篇
  2013年   103篇
  2012年   158篇
  2011年   155篇
  2010年   80篇
  2009年   68篇
  2008年   123篇
  2007年   106篇
  2006年   100篇
  2005年   90篇
  2004年   72篇
  2003年   53篇
  2002年   40篇
  2001年   13篇
  2000年   18篇
  1999年   16篇
  1998年   12篇
  1997年   6篇
  1996年   4篇
  1995年   5篇
  1994年   6篇
  1993年   5篇
  1992年   6篇
  1991年   12篇
  1990年   14篇
  1989年   4篇
  1988年   5篇
  1987年   5篇
  1986年   6篇
  1985年   4篇
  1984年   3篇
  1983年   3篇
  1982年   4篇
  1981年   3篇
  1980年   4篇
  1978年   5篇
  1976年   3篇
  1975年   5篇
  1972年   4篇
  1969年   5篇
  1968年   4篇
排序方式: 共有1864条查询结果,搜索用时 873 毫秒
91.
92.
Cardiac tumours: diagnosis and management   总被引:9,自引:0,他引:9  
Primary cardiac tumours are rare, with an autopsy incidence ranging from 0.001% to 0.030%. Three-quarters of these tumours are benign and nearly half of the benign tumours are myxomas. Metastases to the heart are far more common than primary cardiac tumours. Primary cardiac tumours present with one or more of the symptoms of the classic triad of: cardiac symptoms and signs resulting from intracardiac obstruction; signs of systemic embolisation; and systemic or constitutional symptoms. They are diagnosed by use of transthoracic and transoesophageal echocardiograms, MRI, and CT scan. Whereas surgery is indicated in patients with benign tumours, systemic chemotherapy is indicated in those who have widespread or unresectable malignant disease, and chemotherapy and radiotherapy are usually combined in treatment of patients with primary cardiac lymphomas. The prognosis after surgery is usually excellent in the case of benign tumours but is unfortunately still limited in localised malignant diseases. Patients with sarcomas live for a mean of 3 months to 1 year, and those with lymphomas live up to 5 years if treated, but usually die within 1 month if untreated.  相似文献   
93.
94.
Intussusception in adults is a rare cause for intestinal obstruction and is usually secondary to some lesion in the gastrointestinal tract GIT. We report a case of intestinal obstruction due to ileo-colic intussusception; an inflammatory fibroid polyp formed the leading edge of the intussusceptum, which is a rare polypoidal lesion of the GIT.  相似文献   
95.
Although acetaminophen (APAP)-associated liver injury is well recognized, there are few reports describing APAP nephrotoxicity, and most of them are single cases. It has also been suggested that N-acetylcysteine (NAC), used to treat the hepatotoxicity, may be harmful to the kidneys. To examine this contention and to determine whether renal involvement in APAP poisoning is at all common, we analyzed the incidence and outcome of acute renal dysfunction in patients hospitalized for APAP overdose reported to our regional poison center over a year. Eleven APAP-poisoned patients had elevated liver function tests; nine of them had azotemia. Those with higher AST levels tended to be younger and to have lower APAP levels on admission. Two patients with acute renal injury died after admission. The other seven patients with renal dysfunction recovered in 2 to 7 days. Six of these received NAC; their mean serum creatinine fell from 3.2 +/- 2.0 versus 1.7 +/- 0.9 mg/dL (p < 0.05). We conclude that acute renal failure is not uncommon in APAP poisoning and appears to be unrelated to the degree of liver injury. NAC therapy did not seem to worsen nephrotoxicity.  相似文献   
96.
Background Non malignant tracheo-esophageal fistula is a rare entity, which is usually post traumatic, post inflammatory or could be a delayed presentation of congenital tracheo-esophageal fistula. Patients and Methods In this retrospective study of seven cases, we aim to document and evaluate the causes, presentation and treatment modalities. Results All the cases underwent surgical intervention, with single stage definitive repair in four cases and two stage repair in three cases. There was no mortality, and minimal morbidity. Conclusions Being a benign disease with fatal complications, early diagnosis and early surgical intervention is the key to successful management of non-malignant tracheo-esophageal fistula.  相似文献   
97.
98.
99.
Background: Prior studies suggest that patent foramen ovale (PFO) diameter >4 mm is associated with a high probability of cryptogenic ischemic stroke (CIS). Methods: We evaluated all patients diagnosed with CIS who underwent closure of intra-atrial communication (IAC) using the Amplatzer atrial septal defect (ASD) occluder in our institution between August 1997 and March 2004. For each IAC, echocardiographic diameters and balloon-stretched diameters were recorded. Stretchability index was calculated as the ratio of stretched diameter to unstretched diameter. Results: Fifty-six patients met the inclusion criteria for this study. There was an inverse logarithmic relationship between unstretched IAC diameter and stretchability index. For the 28 smaller defects, the median IAC diameter was 2 mm, and median stretchability index was 5.58 (range 2.6–15). For the 28 larger defects, median diameter was 6 mm, and median stretchability index was 2.38 (range 1.05–5). The difference in stretchability index between the two groups was significant ( P < 0.0001). Conclusion: Our data bring into question the concept that the diameter of the defect would singularly predict the probability of stroke.  相似文献   
100.
BACKGROUND: Despite new therapies, the prevalence of heart failure continues to escalate. The prevalence of diabetes, a risk factor for heart failure, also continues to rise. To further understand the increasing prevalence of heart failure, we compared trends in the prevalence of diabetes among individuals with diagnosed heart failure versus those in the general population. METHODS: Fourteen randomized trials between 1989 and 1999 including subjects with heart failure (n = 34,633) were reviewed. For each trial, the enrollment date was used to estimate the yearly prevalence of diabetes among study participants with heart failure. The prevalence of diabetes in the general population was estimated based on United State's Center for Disease Control statistics from 1989 to 1999. The prevalence of diabetes between heart failure subjects and the general population was compared using a two-sample t-test for independent samples with unequal variances. RESULTS: The prevalence of diabetes increased from 2.6% to 4.0% from 1989 to 1999 in the general U.S. population. Among patients with heart failure, the prevalence of diabetes increased from 13% to 47%. Diabetes prevalence estimates varied significantly (p < 0.001) between the general population and individuals with heart failure during the study period. CONCLUSIONS: The rising prevalence of diabetes may partially explain the growing epidemic of heart failure. Increased efforts targeting diabetes and other cardiovascular risk factors are warranted in attenuating the rising prevalence of heart failure.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号