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   6718篇
  免费   304篇
  国内免费   26篇
耳鼻咽喉   59篇
儿科学   142篇
妇产科学   112篇
基础医学   803篇
口腔科学   95篇
临床医学   757篇
内科学   1744篇
皮肤病学   186篇
神经病学   564篇
特种医学   93篇
外科学   935篇
综合类   38篇
一般理论   2篇
预防医学   548篇
眼科学   106篇
药学   465篇
中国医学   20篇
肿瘤学   379篇
  2024年   4篇
  2023年   41篇
  2022年   28篇
  2021年   169篇
  2020年   96篇
  2019年   192篇
  2018年   301篇
  2017年   164篇
  2016年   176篇
  2015年   206篇
  2014年   183篇
  2013年   298篇
  2012年   592篇
  2011年   635篇
  2010年   309篇
  2009年   222篇
  2008年   513篇
  2007年   528篇
  2006年   479篇
  2005年   458篇
  2004年   413篇
  2003年   406篇
  2002年   372篇
  2001年   22篇
  2000年   20篇
  1999年   19篇
  1998年   34篇
  1997年   18篇
  1996年   17篇
  1995年   13篇
  1994年   8篇
  1993年   16篇
  1992年   13篇
  1991年   8篇
  1990年   5篇
  1988年   3篇
  1987年   6篇
  1986年   5篇
  1985年   5篇
  1984年   5篇
  1983年   3篇
  1982年   11篇
  1981年   7篇
  1980年   6篇
  1979年   2篇
  1977年   3篇
  1976年   2篇
  1975年   2篇
  1973年   2篇
  1970年   2篇
排序方式: 共有7048条查询结果,搜索用时 0 毫秒
31.
32.
OBJECTIVE: To identify features of sexual behavior in women with and without chronic pelvic pain. STUDY DESIGN: A group of 41 women with chronic pelvic pain of more than 6 months' duration and scheduled to undergo laparoscopy or laparotomy were surveyed to obtain information on their sexual activity. The results were compared with a control group of 86 women of similar age and socioeconomic status who underwent planned tubal ligation for permanent contraception. RESULTS: Women with pelvic pain initiated sexual relations at a later age and had a higher rate of dyspareunia than women in the control group. There were no significant differences between groups in any other characteristics of sexual behavior. CONCLUSION: Dyspareunia, the only feature of sexual relations that differed significantly between women with and without chronic pelvic pain, should be accorded greater attention as a painful symptom and not be dismissed as simply a type of sexual dysfunction.  相似文献   
33.
The purpose of this study was to analyze the mortality and its prognostic factors in a Spanish cohort of very low birthweight (VLBW) infants during the period 2002 to 2005. Using the Spanish Society of Neonatology database (SEN 1500), 8942 infants with a birthweight < 1500 g were recruited. The overall mortality was 17.3%. However, this incidence underwent a significant decrease over the study period, from 19.4% in 2002 to 15.2% in 2005 ( P = 0.003). Mortality ranged from 12.4% in 25% of the participating neonatal units to 19.4% in a further 25%. Mortality was higher in outborn infants (25.8%) than in inborn infants (16.6%) ( P < 0.001). The mortality rates of these neonates are also presented by 100-g intervals (401 to 1500) and for the different hospitalization times: in the delivery room, within 24 hours and 28 days of birth, at 36 weeks of postmenstrual age, and on discharge. Of note was that mortality was greatest within 24 hours and 28 days of birth in each of the weight groups ( P < 0.001). In conclusion, in the cohort of infants < 1500 g examined, mortality in the period from 2002 to 2005 was still high, especially among newborns weighing < 1000 g. We did, however, observe a decreasing trend in mortality rates for the participating neonatal units over the 4 study years. Our findings highlight the need to promote intrauterine transport and improve neonatal transport as well as the management of these infants in the delivery room and within the first 28 days of life.  相似文献   
34.
BACKGROUND: Recently the presence of a soluble form of major histocompatibility complex class I chain-related molecule A (sMICA) has been detected in the sera of patients with tumors. Shedding of sMICA by tumor cells downregulates NKG2D-mediated antitumor immunity. The aim of this investigation was to study the possible involvement of sMICA in the allograft acceptance after heart transplantation (HTX). METHODS: We monitored the levels of sMICA by specific enzyme-linked immunosorbent assay (ELISA) in a total of 146 serum samples obtained from 34 heart transplantation patients followed up during the first year post-HTX. RESULTS: The persistence of sMICA expression was correlated with the clinical evolution of these patients. sMICA was detected in the serum of 21 of 34 patients (61.70%) between 15 and 20 days after implantation and was practically absent in pretransplant serum samples. Twenty of these 21 patients (95.24%) with sMICA did not experience episodes of severe rejection during this period (P = 0.0001), whereas sMICA was practically absent in patients with manifestations of severe acute rejection. The longitudinal study of these patients revealed that the presence of sMICA was consistently maintained in 75% of the patients with good graft status during the period of observation. CONCLUSION: This has led us to believe that the presence of levels of sMICA during the first year post-HTX may contribute to allograft acceptance. Additionally, functional studies indicate that sMICA downregulates NKG2D surface expression, which may lead to a functional impairment of cell-mediated cytolysis. These data suggest a significant correlation between the presence of sMICA and a lower incidence of rejection.  相似文献   
35.
Ticks are vectors of pathogens that affect human and animal health worldwide. Ticks and the pathogens they transmit have co-evolved molecular interactions involving genetic traits of both the tick and the pathogen that mediate their development and survival. Proteomics and genomics studies of infected ticks are required to understand tick-pathogen interactions and identify potential vaccine antigens to control tick infestations and pathogen transmission. In this paper, the application of quantitative proteomics to characterize differential protein expression in ticks and cultured tick cells in response to pathogen infection is reviewed. Analyses using (a) two-dimensional differential in gel electrophoresis (DIGE) labeling and (b) protein one-step in gel digestion, peptide iTRAQ labeling, and isoelectric focusing fractionation, both followed by peptide and protein identifications by mass spectrometry resulted in the identification of host, pathogen, and tick proteins differentially expressed in response to infection. Although at its infancy, these results showed that quantitative proteomics is a powerful approach to characterize the tick-pathogen interface and demonstrated pathogen and tick-specific differences in protein expression in ticks and cultured tick cells in response to pathogen infection.  相似文献   
36.
Necrotizing fasciitis is defined as a rapidly progressive infection of the skin and soft tissue that usually involves severe systemic toxicity. The incidence of this infection has increased in the last few decades and is estimated to affect one out of every 100,000 inhabitants in western European countries. This disease is the most serious form of skin and soft tissue infection, due to rapid destruction and necrosis of the fascia and subcutaneous fat, and the development of shock and multiorgan failure in about one third of patients.Although there are several predisposing factors for the development of the disease, especially for type I, or polymicrobial, necrotizing fasciitis, many patients are young and have no underlying chronic diseases, as is the case for type II, or streptococcal, necrotizing fasciitis. The diagnosis is mainly clinical, and urgent surgical consultation is required as soon as possible once suspicion is high, as the main determinant of mortality is the delay in surgical treatment. Overall mortality remains high, affecting more than 25% of patients. Surgical debridement is the mainstay of treatment, along with hemodynamic support and broad-spectrum antibiotics.  相似文献   
37.
38.
Metatarsalgia     
Metatarsalgia is a clinical syndrome characterized by pain in the forefoot. To understand the physiopathogenesis and treatment of this condition, an understanding of the anatomy and biomechanics of the foot is essential. There are a large number of causes of metatarsalgia and some, such as rheumatoid arthritis, may be highly complex. The use of ortheses should be individualized and adjusted to the diagnosis. To prevent this condition, the use of appropriate footwear is essential.  相似文献   
39.
OBJECTIVES:: To compare causes of death (CoDs) from two independent sources: National Basic Death File (NBDF) and deaths reported to the Spanish HIV Research cohort [Cohort de adultos con infección por VIH de la Red de Investigación en SIDA CoRIS)] and compare the two coding algorithms: International Classification of Diseases, 10th revision (ICD-10) and revised version of Coding Causes of Death in HIV (revised CoDe). METHODS:: Between 2004 and 2008, CoDs were obtained from the cohort records (free text, multiple causes) and also from NBDF (ICD-10). CoDs from CoRIS were coded according to ICD-10 and revised CoDe by a panel. Deaths were compared by 13 disease groups: HIV/AIDS, liver diseases, malignancies, infections, cardiovascular, blood disorders, pulmonary, central nervous system, drug use, external, suicide, other causes and ill defined. RESULTS:: There were 160 deaths. Concordance for the 13 groups was observed in 111 (69%) cases for the two sources and in 115 (72%) cases for the two coding algorithms. According to revised CoDe, the commonest CoDs were HIV/AIDS (53%), non-AIDS malignancies (11%) and liver related (9%), these percentages were similar, 57, 10 and 8%, respectively, for NBDF (coded as ICD-10). When using ICD-10 to code deaths in CoRIS, wherein HIV infection was known in everyone, the proportion of non-AIDS malignancies was 13%, liver-related accounted for 3%, while HIV/AIDS reached 70% due to liver-related, infections and ill-defined causes being coded as HIV/AIDS. CONCLUSION:: There is substantial variation in CoDs in HIV-infected persons according to sources and algorithms. ICD-10 in patients known to be HIV-positive overestimates HIV/AIDS-related deaths at the expense of underestimating liver-related diseases, infections and ill defined causes. CoDe seems as the best option for cohort studies.  相似文献   
40.
The power of medicine has lately enhanced the idea of medicalizing any aspects of life that can be perceived as medical problems. Medicine sometimes creates false needs and there is nowadays an increasing number of situations are medicalized with the pretext of treating fake diseases such as spring fatigue, shyness o natural biological processes like menopause.Despite the better life conditions, we now attend more people that complain about discomfort that may have more to do with «feeling sick» than with authentic disease. There is an endless list: sadness, hyperactive children, anorexia, bulimia, vigorexia or problematic teenagers, amongst others. In this article we revise some interventions that, contribute to promote these situations also from the own doctor's office. Everyday adversity acquires today the status of disease, hence the remarkable increase in these consultations in the diverse sanitary services.  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