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   6275篇
  免费   986篇
  国内免费   117篇
耳鼻咽喉   67篇
儿科学   311篇
妇产科学   82篇
基础医学   343篇
口腔科学   181篇
临床医学   450篇
内科学   1138篇
皮肤病学   137篇
神经病学   457篇
特种医学   103篇
外科学   620篇
综合类   554篇
预防医学   1141篇
眼科学   139篇
药学   248篇
  10篇
中国医学   51篇
肿瘤学   1346篇
  2024年   16篇
  2023年   161篇
  2022年   192篇
  2021年   282篇
  2020年   337篇
  2019年   268篇
  2018年   299篇
  2017年   301篇
  2016年   291篇
  2015年   258篇
  2014年   435篇
  2013年   486篇
  2012年   370篇
  2011年   344篇
  2010年   282篇
  2009年   259篇
  2008年   272篇
  2007年   269篇
  2006年   276篇
  2005年   223篇
  2004年   218篇
  2003年   188篇
  2002年   178篇
  2001年   147篇
  2000年   103篇
  1999年   86篇
  1998年   76篇
  1997年   83篇
  1996年   63篇
  1995年   57篇
  1994年   66篇
  1993年   52篇
  1992年   55篇
  1991年   44篇
  1990年   34篇
  1989年   41篇
  1988年   37篇
  1987年   21篇
  1986年   26篇
  1985年   34篇
  1984年   26篇
  1983年   20篇
  1982年   22篇
  1981年   17篇
  1980年   13篇
  1979年   11篇
  1978年   6篇
  1977年   9篇
  1976年   5篇
  1974年   5篇
排序方式: 共有7378条查询结果,搜索用时 15 毫秒
31.
Background Down syndrome is one of the commonest causes of intellectual disability. As life expectancy improves with early and more intensive surgical and medical treatments, people with the disorder are more likely to exhibit classic morbidity and mortality patterns and be diagnosed with diseases such as cancer. Methods A profile of cancer cases among people with Down syndrome has been compiled, based on the analysis of a linked data set that included information from the Disability Services Commission of Western Australian and the State Cancer Registry. Results and conclusions Although the total age‐ and sex‐standardized incidence ratios (SIRs) for people with Down syndrome were similar to that for the general population, SIRs for leukaemia were significantly higher while the incidence of certain other types of cancers was reduced. Overall, there was a lower incidence of solid tumours in Down syndrome, possibly reflecting the age profile of the study cohort.  相似文献   
32.
To better understand the impact of incident Parkinson's disease (PD) on the Veteran's Health Administration (VHA) and to develop methods applicable to future epidemiological research, we performed a medical record review study at a tertiary referral VHA medical center. Searching the local data base, we identified 782 veterans with diagnostic codes for PD or secondary parkinsonism (SP) between 1998 and 2000. Based on structured medical record review, a movement disorders specialist confirmed diagnoses for incident parkinsonism cases. Among the 782, 191 incident parkinsonism cases were identified (100 PD, 75 SP, and 16 Parkinson's Plus). Incident PD cases were older at diagnosis (74.5 vs. 70.4 yr; P < 0.05) and more likely to be white (81% vs. 62; P < 0.07) than incident SP cases. Diagnostic codes were insufficient to distinguish between incident PD and SP (positive predictive value, 57% and 39%, respectively), and VHA sources failed to identify 21% of confirmed deaths among the incident PD cohort by November 2004. Although the large number of incident cases identified suggests PD is an important cause of disability among elderly VHA users, observed limitations of VHA sources for identifying incident PD cases and determining their vital status should be considered when designing future studies.  相似文献   
33.
This retrospective analysis reviews the clinical experience of a major urban referral hospital with diffuse malignant pleural mesothelioma during the 14-year period from 1973 through 1986. Seventy-five cases of definite or equivocal mesothelioma were identified. There were four cases of primary malignant peritoneal mesothelioma, seven cases of benign fibrous mesothelioma, and 64 cases of diffuse malignant pleural mesothelioma. In 43 cases (67%) of diffuse malignant pleural mesothelioma, there was historic evidence of asbestos exposure. In 21 cases (33%), there was no known history of asbestos exposure. An increase in annual incidence of diffuse malignant pleural mesothelioma was observed over the study period, from three cases in 1973 to ten cases in 1986. Despite greater awareness of this disease, the diagnosis remains a difficult one to establish given the nonspecific symptoms, signs and radiographic appearance, variable histologic appearance, and poor diagnostic sensitivity and specificity of thoracentesis and closed pleural biopsy. Thoracotomy, thoracoscopy, and CT-guided needle biopsies gave higher yields and are the diagnostic measures of choice when diffuse malignant pleural mesothelioma is suspected.  相似文献   
34.
BACKGROUND: The incidence of congenital hypothyroidism (CH) is expected to be elevated in iodine-deficient areas. In this study, the authors aimed to determine the incidence of transient and permanent CH in a large city which is known to be in the zone of moderate iodine deficiency. METHODS: Newborn babies in Bursa, Turkey, were screened by measurement of serum thyroid-stimulating hormone (TSH) obtained by heel prick. The babies who had a serum TSH >20 mIU/L were recalled for measurement of T4 and TSH in venous serum. RESULTS: A total of 11 770 newborns were screened over a period of 9 years. The incidence of CH was found to be 1/840. However, after excluding the transient cases, permanent CH was diagnosed in 1/2354. It was impossible to distinguish transient patients from permanent CH by initial laboratory tests (P > 0.05). The estimated power of the study in determining the incidence of CH in the population was 90% (P < 0.05). CONCLUSION: The authors conclude that the incidence of CH is very high in their population which warrants a country-wide neonatal screening program. Since transient cases cannot be distinguished and untreated transient hypothyroidism may also cause mental retardation, treatment must be started as early as possible with frequent monitoring to optimize the outcome and identify the transient patients.  相似文献   
35.
新疆奎屯地区口腔粘膜疾病调查   总被引:1,自引:0,他引:1  
本文介绍新疆奎屯地区常见口腔粘膜疾病患病情况,其罹患率与上海地区同类调查相比,除白斑外其他病种罹患率均偏高,可能与生活水平偏低或某些全身疾病有关。  相似文献   
36.
AIM: Urothelial carcinoma (UC) can occur multifocally in the whole urothelium. A higher rate of bilateral metachronous upper tract (UT) UC was noted in Taiwan. The incidence and risk factors were largely unknown and hence were explored in the study. METHODS: From January 1977 through June 2003, 462 patients with unilateral UT-UC were studied retrospectively. The cumulative incidence of contralateral recurrence was analysed with the Kaplan-Meier analysis. Potential risk factors for contralateral recurrence including age, smoking, bladder cancer, renal function, diagnostic year etc. were evaluated with the log-rank test. Independent risk factors were identified by using the Cox regression analysis. RESULTS: The median follow-up time was 34 months (6-337). Among the 462 patients, 52 (11.3%) developed metachronous contralateral UC. The 2, 5, and 10-year contralateral disease-free survivals were 93.5%, 84.0%, and 75.7%, respectively. The median time to contralateral recurrence was 31.0 months. With the univariate analysis, only poor renal function (serum creatinine < or > OR =2.0 mg/dL, P < 0.001) and late diagnostic year (before or after 1990, P < 0.001) were risk factors for contralateral recurrence. In the multivariate analysis, poor renal function (hazard ratio: 2.98; 95% confidence interval: 1.67-5.33; P < 0.001) and late diagnostic year (hazard ratio: 4.27; 95% confidence interval: 1.71-10.65; P = 0.002) remained independent risk factors. CONCLUSIONS: The incidence of metachronous UT-UC is high in Taiwan. Patients who had either chronic renal insufficiency or a disease diagnosed after 1990 had a higher risk of contralateral recurrence.  相似文献   
37.
对1971—1990年间加拿大不列颠哥伦比亚癌症中心收治的428例鼻咽癌病人的发病和治疗情况进行分析。其中,中国人占303例(71%),白种人116例(27%)。中国人在该省鼻咽癌的年发病率是白种人的64倍,其中又以在中国出生的发病率最高,分别为白种人的104倍和北美出生的中国人的16倍。本组总的5年和10年生存率分别为51%和39%,颈淋巴结阴性的病人5年生存率达64%;而阳性的病人只有44%。鼻咽癌的预后与它的临床分期、病理类型、治疗前有无做颈淋巴结活检,以及性别有关,而与病人的人种和出生地无关。  相似文献   
38.
The incidence, risk factors, and prognosis for Mycobacterium tuberculosis (MTB) infection have not been reported in a national population of renal transplant recipients. We performed a retrospective cohort study of 15,870 Medicare patients who received renal transplants from January 1, 1998 to July 31, 2000. Cox regression analysis derived adjusted hazard ratios (AHR) for factors associated with a diagnosis of MTB infection (by Medicare Institutional Claims) and the association of MTB infection with survival. There were 66 renal transplant recipients diagnosed with tuberculosis infection after transplant (2.5 cases per 1000 person years at risk, with some falling off of cases over time). The most common diagnosis was pulmonary TB (41 cases). In Cox regression analysis, only systemic lupus erythematosus (SLE) was independently associated with TB. Mortality after TB was diagnosed was 23% at 1 year, which was significantly higher than in renal transplant recipients without TB (AHR, 4.13, 95% CI, 2.21, 7.71, p < 0.001). Although uncommon, MTB infection is associated with a substantially increased risk of mortality after renal transplantation. High-risk groups, particularly those with SLE prior to transplant, might benefit from intensified screening.  相似文献   
39.
目的 了解我校高级知识分子糖尿病患病情况及分析影响患病的相关因素。方法 采用流行病学统计方法分析数据。结果 糖尿病患病率为 17.78%,高于 1980年全国和 1995年全省患病率水平。患病率随年龄增长而增高 ,70岁以上为高峰 ,男女性别间患病率无差异。结论 糖尿病与高血压、高脂血症和肥胖有密切相关 ,应制定相应糖尿病防治措施。  相似文献   
40.
Objective: To explore the trends of incidence and mortality rates of stroke in Hanzhong rural population. Methods: Acting as the WHO MONICA project. Results: The incidence rate of stroke was 152. 9/100 000. There was decline trend in male(P <0. 05). The mortality rate of stroke was 115.9/100 000. There was no significant decline trend during 18-year period (P < 0. 05). The incidence and mortality rates of stroke of male were higher than those of female(P<0. 05). The incidence and mortality rates were all increased with age(P <0. 01 ). Conclusion: It must stick to the long- term prevention measures to decrease incidence rate, and improve the condition of medical treatment to reduce the mortality rate in rural population.  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