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   10366篇
  免费   645篇
  国内免费   54篇
耳鼻咽喉   96篇
儿科学   373篇
妇产科学   159篇
基础医学   1161篇
口腔科学   348篇
临床医学   731篇
内科学   2398篇
皮肤病学   231篇
神经病学   504篇
特种医学   412篇
外科学   1376篇
综合类   186篇
一般理论   5篇
预防医学   591篇
眼科学   492篇
药学   978篇
中国医学   51篇
肿瘤学   973篇
  2023年   56篇
  2022年   128篇
  2021年   255篇
  2020年   137篇
  2019年   191篇
  2018年   249篇
  2017年   161篇
  2016年   191篇
  2015年   254篇
  2014年   331篇
  2013年   414篇
  2012年   618篇
  2011年   656篇
  2010年   339篇
  2009年   335篇
  2008年   467篇
  2007年   493篇
  2006年   507篇
  2005年   449篇
  2004年   418篇
  2003年   393篇
  2002年   359篇
  2001年   295篇
  2000年   310篇
  1999年   224篇
  1998年   121篇
  1997年   87篇
  1996年   80篇
  1995年   79篇
  1994年   58篇
  1993年   62篇
  1992年   160篇
  1991年   168篇
  1990年   161篇
  1989年   146篇
  1988年   146篇
  1987年   171篇
  1986年   148篇
  1985年   117篇
  1984年   117篇
  1983年   83篇
  1982年   59篇
  1980年   56篇
  1979年   71篇
  1977年   63篇
  1976年   66篇
  1975年   66篇
  1974年   81篇
  1973年   65篇
  1972年   57篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
101.
One-stage surgery was successfully performed in a 44-year-old hypertensive man with uncontrolled angina, multiple coarctations of the thoracic and abdominal aorta, and a previous subtotal gastrectomy. There was a gradient of 120 mm Hg between the thoracic and abdominal aorta. A graft was placed retroperitoneally from the infrarenal aorta to the ascending aorta and was followed by a coronary artery bypass graft. Twenty-four months postoperatively, the patient was free of angina, and his hypertension was easily controlled.  相似文献   
102.
Aim

The primary objective of this study was to investigate temporal changes in HIV testing rates and quantify the degree to which these trends can be attributed to certain socio-economic characteristics, as well as exposure to information sources.

Subjects and methods

Data from a nationally representative sample of 30,020 sexually active black Africans who participated in the first, second, third and fourth South African National HIV, Behaviour and Health Surveys conducted in 2002, 2005, 2008 and 2012, respectively. Multivariable logistic regression models and population-attributable risks were calculated for the socio-economic characteristics and the information sources.

Results

The socio-economic characteristics of the survey participants remained stable over time, while HIV testing rates increased substantially from 20% in 2002 to 70% in 2012. However, there was little improvement in condom use rates. Combined impact of education, employment and geographical locations were associated with increased levels of HIV testing rates. Most of the survey participants (> 80%) were exposed to several mass-media and interpersonal information sources. The combined impact of mass-media tools on HIV testing rates ranged between 48 and 60%, while 40–50% of the HIV tests were collectively attributed to the interpersonal information sources.

Conclusion

We observed significant temporal changes in population-level impacts of several key socio-economic characteristics and information sources on HIV testing rates. Widespread nationwide HIV awareness efforts led to significant increases in access to testing facilities and substantial increases in HIV testing rates over time. However, this increase was not mirrored in condom use behaviour.

  相似文献   
103.
Maternal and Child Health Journal - The Maternal and Child Health (MCH) Pipeline Training Program, promotes development of a diverse health workforce by training undergraduate students from...  相似文献   
104.
Provision of safe drinking water in the United States is a great public health achievement. However, new waterborne disease challenges have emerged (e.g., aging infrastructure, chlorine-tolerant and biofilm-related pathogens, increased recreational water use). Comprehensive estimates of the health burden for all water exposure routes (ingestion, contact, inhalation) and sources (drinking, recreational, environmental) are needed. We estimated total illnesses, emergency department (ED) visits, hospitalizations, deaths, and direct healthcare costs for 17 waterborne infectious diseases. About 7.15 million waterborne illnesses occur annually (95% credible interval [CrI] 3.88 million–12.0 million), results in 601,000 ED visits (95% CrI 364,000–866,000), 118,000 hospitalizations (95% CrI 86,800–150,000), and 6,630 deaths (95% CrI 4,520–8,870) and incurring US $3.33 billion (95% CrI 1.37 billion–8.77 billion) in direct healthcare costs. Otitis externa and norovirus infection were the most common illnesses. Most hospitalizations and deaths were caused by biofilm-associated pathogens (nontuberculous mycobacteria, Pseudomonas, Legionella), costing US $2.39 billion annually.  相似文献   
105.
PurposeTo report outcomes of Debridement, Antibiotic therapy and Implant Retention (DAIR) for periprosthetic knee joint infections (PJI) in the Indian population and to study factors influencing outcomes.MethodsThis was a Retrospective study of 80 cases of acute PJI after total knee arthroplasty who were treated by DAIR, within 2 weeks of onset of infection. A standardised institutional management protocol was applied to all cases. Patients were followed up for a minimum 1 year. Outcomes of DAIR were classified as successful or unsuccessful based on resolution or persistence of infection, and subsequent requirement of revision surgery. Influence of factors, like comorbidities, culture status and microbiological characteristics of causative organism, on outcomes was assessed.ResultsOverall 55 patients (68.75%) had successful eradication of infection after DAIR. 27 (33.7%) patients were culture negative and 53 (66.2%) patients grew organisms on culture. There was no statistically significant difference in outcomes (p = 0.082) between culture-positive cases (69.8% success rate) and (66.7% success rate) in culture negative cases. Furthermore, no difference in outcomes was observed in culture-positive patients between those who grew Gram-positive organisms versus Gram-negative organisms (p = 0.398) Similarly, patient comorbidities did not significantly alter the outcomes after DAIR (p = 0.732).ConclusionOur study demonstrates that early DAIR within 2 weeks of onset of infection using a standard protocol during surgery and postoperatively can result in good outcomes. Patient comorbidities, culture status (positive versus negative), Gram staining characteristics of organisms and the identity of pathogenic bacteria did not influence outcomes of DAIR for acute PJI.  相似文献   
106.
107.
Pro-inflammatory cytokine and chemokines genes drive prostate cancer progression and metastasis: molecular mechanism update and the science that underlies racial disparity. comprehensive review article.Isaac J. Powell, S. Chinni, S.S. Reddy, Alexander Zaslavsky, Navnath Gavande Introduction: In 2013 we reported that with the use of bioinformatics and ingenuity pathway network analysis we were able to identify functional driver genes that were differentially expressed among a large population of African American men (AAM) and European American men (EAM). Pro-inflammatory cytokine genes were found to be more interactive and more expressed among AAM and have been found to be functional drivers of aggressive prostate cancer (CaP) and aggressiveness in other solid tumors. We examined these genes and biological pathways initiated by these cytokines in primary CaP tissue.Method We unravel the gene network and identified biologic pathways that impacted activation of the androgen receptor, mesenchymal epithelial transition (invasion) and chemokines associated with metastasis in the CaP tissue from 639 radical prostatectomy specimens.Results Biologic pathways identified by unraveling pro-inflammatory genes from our network, more expressed among AAM compared to EAM, were tumor necrosis factor (TNF), IL1b, IL6, and IL8. IL6 and IL8 are downstream of TNF activity and are known activators of androgen receptor and through mediators promote CaP cell proliferation. TNF and IL1b mediate tumor cell invasiveness through the activation of MMP (matrix metalloproteinase) which down regulates E-Cadherin to initiate epithelial mesenchymal transition which allows cells to become invasive in the microenvironment. Ultimately our network analysis indicates that TNF and IL1b activate CXCR4 receptor on CaP cells, which facilitates metastatic progression reportedly by binding to CXCL12 on lipid rafts and tumor implantation in the bone marrow.Conclusion Our retrospective biologic mechanistic model reveals a set of pro-inflammatory cytokines and chemokines that drive CaP aggressiveness, tumor heterogeneity, progression and metastasis. A prospective multi-institutional study needs to be conducted for clinical validation as well consideration of targeted therapy.  相似文献   
108.
109.
A key recommendation of the National AIDS Control Programme‐IV of India was to develop new strategies for geo‐prioritization of the human immunodeficiency virus (HIV) epidemic. We conducted this study to categorize the districts in Maharashtra (India) based on a multidimensional framework for geo‐prioritization of services. Programmatic data on trends of HIV prevalence, coverage of marginalized populations and vulnerability factors were included. A composite indicator based on these was developed, and the cumulative score was calculated for each district. HIV prevalence among general population has declined steadily from 0.60% in 2007 to 0.33% in 2017. The programme coverage was stable but inadequate for men who have sex with men (MSM). The coverage for female sex workers (FSWs) was inadequate and reduced over time. Nine districts were categorized as high priority, 13 as moderate priority and 11 were classified as low‐priority districts based on burden and vulnerability for HIV. The high‐priority districts were Pune, Solapur and Yavatmal for FSW interventions and Pune, Thane and Latur for MSM interventions. This multidimensional indicator is based on existing programmatic data, dynamic and can be made state‐specific. It is useful to categorize and prioritize districts for allocation of resources and geo‐prioritization of services in resource limited settings.  相似文献   
110.
A case of tropical (filarial) eosinophilia (TE) presented with vesicular and bullous eruptions. The patient had skin and mucosal blistering. Histopathological changes were that of bullous pemphigoid. The patient had very high eosinophilia with abnormal vacuoles in the cytoplasm. ELISA test was positive for filarial antibodies. There were no pulmonary signs or symptoms. X-ray chest was normal. The patient responded well to diethylcarbamazine.  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