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   2994篇
  免费   148篇
  国内免费   44篇
耳鼻咽喉   42篇
儿科学   112篇
妇产科学   49篇
基础医学   297篇
口腔科学   35篇
临床医学   274篇
内科学   695篇
皮肤病学   177篇
神经病学   214篇
特种医学   247篇
外科学   458篇
综合类   36篇
预防医学   198篇
眼科学   94篇
药学   138篇
中国医学   5篇
肿瘤学   115篇
  2022年   14篇
  2021年   35篇
  2020年   18篇
  2019年   49篇
  2018年   53篇
  2017年   43篇
  2016年   50篇
  2015年   62篇
  2014年   54篇
  2013年   140篇
  2012年   93篇
  2011年   123篇
  2010年   120篇
  2009年   117篇
  2008年   119篇
  2007年   119篇
  2006年   106篇
  2005年   140篇
  2004年   90篇
  2003年   104篇
  2002年   100篇
  2001年   82篇
  2000年   95篇
  1999年   85篇
  1998年   99篇
  1997年   85篇
  1996年   99篇
  1995年   65篇
  1994年   69篇
  1993年   55篇
  1992年   44篇
  1991年   35篇
  1990年   50篇
  1989年   60篇
  1988年   62篇
  1987年   44篇
  1986年   44篇
  1985年   40篇
  1984年   26篇
  1983年   22篇
  1982年   23篇
  1981年   20篇
  1980年   14篇
  1979年   19篇
  1978年   17篇
  1977年   18篇
  1976年   20篇
  1975年   14篇
  1973年   17篇
  1965年   10篇
排序方式: 共有3186条查询结果,搜索用时 15 毫秒
51.
52.
53.
The rise of next generation consoles game, with their share of sport simulations, has caused appearance of new sport injuries. We present a case of a traumatic rupture of the calcaneal tendon, after a game of virtual sport. It concerned a non-athletic 40-year-old woman. The surgery was performed with a very good long-term result. Literature review demonstrated the extent of these pathologies, with a prevalence of musculoskeletal troubles.  相似文献   
54.
55.
The myeloproliferative syndrome induced by the myeloproliferative sarcoma virus (MPSV) in DBA/2 mice stimulates the proliferation of pluripotent hemopoietic stem cells (HSC) and of progenitors committed toward granulomacrophagic and erythroid cell lines. This stimulation may result from a direct effect of the MPSV on HSC or from an indirect effect via locally secreted factors. Normal isogenic bone marrow cells were incubated in the mixed colony-forming unit system in semisolid medium supplemented with conditioned media obtained after incubating neoplastic spleen cells for 3 days at 37 degrees C. These spleen conditioned media contain an activity that is physically separable from MPSV by ultracentrifugation and which, in the presence of a very low quantity of erythropoietin, can induce in vitro the proliferation and differentiation of pluripotent HSC, detected by this Mix-CFU technique. We termed this activity mixed-colonies promoting activity (MPA). These results suggest that the hyperplasia of the nonlymphoid hematopoietic system in the neoplastic spleen results from an indirect effect of the MPSV on pluripotent HSC via locally secreted factors.  相似文献   
56.
57.
We employed the research-to-practice consensus workshop (RTP; workshops held in New York City and Tompkins County, New York, in 2013) model to merge researcher and practitioner views of translational research priorities in palliative care. In the RTP approach, a diverse group of frontline providers generates a research agenda for palliative care in collaboration with researchers. We have presented the major workshop recommendations and contrasted the practice-based research priorities with those of previous consensus efforts. We uncovered notable differences and found that the RTP model can produce unique insights into research priorities. Integrating practitioner-identified needs into research priorities for palliative care can contribute to addressing palliative care more effectively as a public health issue.Over the past 2 decades, palliative care has become established as a promising approach for addressing the needs of individuals with life-threatening illnesses from a holistic, interdisciplinary perspective. For this project, we defined palliative care as an approach that improves the quality of life of patients and families facing the problems encountered in life-threatening illness by preventing and relieving suffering. Core components of palliative care include providing relief from pain and other distressing symptoms, affirming dying as a normal process, integrating psychological and spiritual aspects of care, enhancing the quality of life of patients, and offering support systems to patients and their families to help them live as fully as possible until death occurs.Research suggests that palliative care results in positive patient outcomes, greater patient and family satisfaction, and significant cost savings.1,2 The American Public Health Association, the World Health Organization, and the Institute of Medicine3–6 have identified the development of a robust palliative care delivery system as a key public health issue because of the documented ability of palliative care to deliver effective and efficient patient- and symptom-focused care to a growing population in need.In its 2013 report the American Public Health Association specifically detailed the public health implications of palliative care, acknowledged the growing burden of advanced chronic illness and disease in older adults, and recommended key steps to address the problem. This policy statement called for federal, state, and local efforts to promote effective symptom management in populations with serious illness or at the end of life. Other recommended initiatives included the development of a palliative care workforce, educational programs to improve uptake and use of palliative and hospice care, and research funding to support the expansion of palliative care initiatives. Achieving these goals will require moving beyond traditional medical practices to include both policies and initiatives at the public health level.Despite the potential of palliative care to address the mental and physical health needs of individuals with advanced illness, significant knowledge gaps impede its reach and effectiveness. Reports from scientific bodies and consensus workshops have highlighted weaknesses in the literature and called for more research on palliative care and improved research methods.7–10 Thus, although both interest in and demand for palliative care are increasing, reviews of the knowledge base continue to lament the lack of research on many key issues.11,12Especially urgent is a research agenda that fits most closely with the needs of providers who deliver palliative care. The systematic engagement of community practitioners in a consensus process can lead to particularly useful and actionable recommendations for research,13–15 which are greatly needed at this stage in the development of the field. Therefore, to shed new light on research priorities in palliative care, we used a structured, participatory method designed to solicit practitioner input on research priorities: the research-to-practice consensus workshop (RTP) model.16We employed the RTP approach to identify knowledge gaps and types of studies that should be conducted to improve providers’ ability to deliver palliative care most effectively. This model harnesses practice wisdom by engaging clinicians, agency staff, and other practitioners with researchers in a process of articulating and refining research questions and research priorities that honors scientific expertise and practice wisdom.  相似文献   
58.
59.
Embryonic tissues were obtained from normal (C) and thyroidectomized (T) rats between 9 and 21 days of pregnancy. We determined the number and weight, as well as the T4 and T3 contents (RIA), of 9- to 12-day-old embryotrophoblasts, of 13- to 21-day-old embryos and placentas, and of liver, lung, and brain from 20- and 21-day-old fetuses. T4 and T3 were found in all samples obtained from C dams, both before and after onset of fetal thyroid function. Despite low levels of both iodothyronines in fetal plasma near term, their concentrations in fetal brain and lung had reached half the maternal values. The T3/T4 ratio in fetal organs was the same, or higher, than in adult rats. Maternal thyroidectomy resulted in a marked decrease of the number and individual weights of viable conceptuses, throughout gestation. Fetal organ weights near term were also decreased, and changes were found in brain DNA and protein concentrations. T4 and T3 were undetectable in all embryotrophoblasts, embryos and placentas obtained from T dams before onset of fetal thyroid secretion. They were still markedly reduced in 21-day-old placentas. Total extrathyroidal contents of T3 and T4 in 20- and 21-day-old fetuses from T dams were also low as compared to those from normal mothers, but individual organs were not affected to the same degree. Thus concentrations were decreased in the carcass (whole embryo minus the trachea + thyroid + liver + lung + brain), but normal in the brain. These results show that maternal hypothyroidism is accompanied by thyroid hormone deficiency of the conceptus before the fetal thyroid functions. After this, alterations of T4 and T3 concentrations persist until term. Development is also delayed. Thus, adverse effects of maternal hypothyroidism may be due, at least in part, to the thyroid hormone deficiency of the embryonic tissues, and not only to the hypothyroid condition of the mother.  相似文献   
60.
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