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   8139篇
  免费   2483篇
  国内免费   47篇
耳鼻咽喉   142篇
儿科学   131篇
妇产科学   246篇
基础医学   131篇
口腔科学   303篇
临床医学   3313篇
内科学   1429篇
皮肤病学   220篇
神经病学   939篇
特种医学   188篇
外科学   1459篇
综合类   7篇
预防医学   1218篇
眼科学   411篇
药学   71篇
肿瘤学   461篇
  2024年   81篇
  2023年   476篇
  2022年   80篇
  2021年   203篇
  2020年   360篇
  2019年   131篇
  2018年   624篇
  2017年   700篇
  2016年   635篇
  2015年   655篇
  2014年   760篇
  2013年   772篇
  2012年   223篇
  2011年   228篇
  2010年   472篇
  2009年   624篇
  2008年   214篇
  2007年   142篇
  2006年   168篇
  2005年   125篇
  2004年   80篇
  2003年   67篇
  2002年   83篇
  2001年   191篇
  2000年   73篇
  1999年   176篇
  1998年   250篇
  1997年   241篇
  1996年   298篇
  1995年   216篇
  1994年   215篇
  1993年   165篇
  1992年   132篇
  1991年   112篇
  1990年   69篇
  1989年   81篇
  1988年   68篇
  1987年   68篇
  1986年   63篇
  1985年   41篇
  1984年   42篇
  1983年   30篇
  1982年   34篇
  1981年   18篇
  1980年   22篇
  1979年   14篇
  1978年   16篇
  1977年   10篇
  1971年   12篇
  1955年   8篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
This study was designed to assess the accuracy of end-tidalPco 2 and transcutaneousPco 2 as measurements of arterialPco 2 in extubated, spontaneously breathing patients recovering from general anesthesia. In 30 patients, measurement of arterial transcutaneous, and end-tidalPco 2 were taken simultaneously with body temperature approximately every 15 minutes over a 2-hour period. ArterialPco 2 values were corrected for body temperature. Values for Paco 2 were compared with those forPetCO2 and Psco 2 by linear regression analysis and by calculation of bias ± precision. Thirty-six percent of the capnogram tracings obtained did not develop a plateau phase. We found poor correlation between end-tidal and arterialPco 2 regardless of the shape of the capnogram tracing, as well as poor correlation between transcutaneous and arterialPco 2. Although the measurements of bias and precision of noninvasivePco 2 monitors in this population are comparable to studies in other populations, we advise caution in relying on the routine use ofPetCO2 or Psco 2 for the noninvasive assessment of respiratory depression in extubated, spontaneously breathing patients recovering from general anesthesia.  相似文献   
82.
N-I Max Kjellman  MD  PhD    Michael T Stevens  BSc  CStat   《Allergy》1995,50(S21):14-22
A programme of clinical studies was carried out to determine the basic efficacy and safety of 2% nedocromil sodium eye drops (Tilavist) in treating allergic conjunctivitis, in 2,905 patients from 3–76 years of age. Results of all the double-masked placebo comparative studies completed to date - five in vernal keratoconjunctivitis (VKC), five in perennial (PAC) and 16 in seasonal allergic conjunctivitis (SAC) - have been assessed in a statistical overview analysis. Nedocromil sodium, administered four times daily to 153 patients with VKC, was significantly more effective than placebo (155 patients) and in the clinicians' opinion gave good control in 76% of cases, compared with 46% for placebo (p < 0.001). Patients with chronic symptoms of PAC also responded better to nedocromil sodium given four times daily (n = 146) rather than twice daily (n = 86), and significantly more patients (p < 0.001) were effectively controlled by four times daily treatment with nedocromil sodium (72%) than with placebo (47%; n= 156). Twice-daily dosage with nedocromil sodium (n = 677) was adequate for SAC, however, and the treatment was statistically better than placebo (p < 0.01-p < 0.001) whether dosed twice or four times daily. Speed of action was assessed in seven SAC studies in which 79% of all patients (n = 295) using nedocromil sodium had experienced relief of symptoms when questioned, half of them within 15 minutes and 74% during the first hour after dosing. Test treatments were well-accepted by both adults and children, and there were no major adverse events. Minor irritations reported more frequently with nedocromil sodium than placebo were stinging or burning of the eyes on application of the drops and a distinctive taste, noted by 5% of the active treatment group (n = 1,552).  相似文献   
83.
This work describes our experience in reviewing the performance criteria for display systems and how we have implemented a practical approach to the assessment of the workstation environment in a large tertiary care hospital. The acceptance criteria contained in the draft report of Topic Group 18 of the American Association of Physicists in Medicine (AAPM) were used as a basis for assessment of primary and secondary displays. A telescopic photometer was used to measure the maximum luminance and the contrast ratio of the image for the displays used in our radiology department and in the operating and emergency rooms using the standard Society of Motion Picture and Television Engineers (SMPTE) pattern, in ambient light and with light decreased as much as possible. About half of the displays met the AAPM criteria for minimum luminance and contrast ratio in low light. None of the systems met the contrast ratio criteria in ambient light. The challenges in improving the performance and calibrating displays are discussed.  相似文献   
84.
Atypical carcinoid tumour of the thymus: a study of eight cases   总被引:1,自引:0,他引:1  
Atypical carcinoids of the thymus are rare neoplasms of uncertain prognosis. We have studied eight cases (six male, two female; age range 48–60 years, mean 55 years), none with evidence of a paraneoplastic neuroendocrine syndrome. Tumour size was large and ranged from 7.5 to 10 cm. Microscopically, all had a nesting/insular or trabecular pattern, eosinophilic cytoplasm, round nuclei with fine chromatin and small nucleoli. No small cell features were evident. Mitotic activity ranged from 2 to 21 per 1.52 mm2. Focal necrosis was seen in all cases. All were positive for cytokeratin (AE1/AE3, CAM 5.2) and the neuroendocrine markers NSE, synaptophysin and chromogranin; five cases were positive for calcitonin. On electronmicroscopy all contained dense core granules, often numerous. Three cases were stage I and five stage III (infiltrating lung or chest wall). Follow-up information was available in four cases (one stage I and three stage III): the stage I tumour had local recurrence and metastasis to the lung within a year whilst the three patients with stage III tumours died of liver, bone and brain metastases within 3 years.  相似文献   
85.
As a philosophical position, pragmatism can be critiqued to distinguish truth only with methods that bring about desired results, predominantly with scientific enquiry. The article hopes to dismiss this oversimplification and propose that within mental health nursing, enquiry enlightened by pragmatism can be anchored to methods helping to tackle genuine human problems. Whilst pragmatists suggest one reality exists, fluctuating experiences and shifting beliefs about the world can inhabit within; hence, pragmatists propose reality has the potential to change. Moreover, pragmatism includes being cognisant of what works to whom reality concerns, making reality context-driven, with a view to understand how actions shape experiences so what is generated has usefulness. Hence, it somewhat follows pragmatism can inform mental health nursing, after all, nursing is a discipline of action, and awareness is needed in how actions produce experiences that patients find helpful. Given the principles of recovery are preferably adopted in mental health care, the paper will explore how pragmatism can help nurses move towards that goal; specifically, with patients voicing their experiences. This is because like pragmatism, recovery subscribes to hope that reality can progress, and through meaningful experiences and beliefs, patients have expertise about personal difficulties alongside how life may flourish, despite mental illness.  相似文献   
86.
The importance of developing cultural competence among healthcare professionals is well recognized. However, the widespread reports of insensitivity and deficiencies in care for culturally diverse patients illuminate the need to review how cultural competence development is taught, learnt and applied in practice. Unless we can alter the ‘hearts and minds’ of practising nurses to provide the care that they know they should, culturally insensitive care will continue operating in subtle ways. This paper explores the ideas behind nurses’ actions and omissions when caring for culturally diverse patients and proposes the need to examine cultural competence development through a moral reasoning lens. Examining cultural competence development through a moral reasoning lens can help empower nurses, whilst nurturing commitment and courage to providing quality care that meets the needs of culturally diverse patients. The model of morality provides a framework that explores how moral motivation and behaviour occur and can provide a vehicle for critically examining the knowledge, skills and attitudes required to provide culturally responsive care.  相似文献   
87.
88.
89.
90.
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