全文获取类型
收费全文 | 1799篇 |
免费 | 201篇 |
国内免费 | 49篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 112篇 |
妇产科学 | 93篇 |
基础医学 | 174篇 |
口腔科学 | 44篇 |
临床医学 | 192篇 |
内科学 | 502篇 |
皮肤病学 | 43篇 |
神经病学 | 41篇 |
特种医学 | 234篇 |
外科学 | 134篇 |
综合类 | 113篇 |
一般理论 | 4篇 |
预防医学 | 172篇 |
眼科学 | 8篇 |
药学 | 71篇 |
中国医学 | 3篇 |
肿瘤学 | 100篇 |
出版年
2023年 | 22篇 |
2022年 | 10篇 |
2021年 | 41篇 |
2020年 | 28篇 |
2019年 | 21篇 |
2018年 | 35篇 |
2017年 | 48篇 |
2016年 | 46篇 |
2015年 | 34篇 |
2014年 | 80篇 |
2013年 | 87篇 |
2012年 | 51篇 |
2011年 | 52篇 |
2010年 | 82篇 |
2009年 | 94篇 |
2008年 | 50篇 |
2007年 | 92篇 |
2006年 | 65篇 |
2005年 | 46篇 |
2004年 | 52篇 |
2003年 | 33篇 |
2002年 | 36篇 |
2001年 | 49篇 |
2000年 | 32篇 |
1999年 | 36篇 |
1998年 | 82篇 |
1997年 | 71篇 |
1996年 | 65篇 |
1995年 | 60篇 |
1994年 | 50篇 |
1993年 | 52篇 |
1992年 | 29篇 |
1991年 | 19篇 |
1990年 | 38篇 |
1989年 | 39篇 |
1988年 | 37篇 |
1987年 | 20篇 |
1986年 | 35篇 |
1985年 | 30篇 |
1984年 | 21篇 |
1983年 | 24篇 |
1982年 | 11篇 |
1981年 | 12篇 |
1980年 | 11篇 |
1979年 | 15篇 |
1978年 | 16篇 |
1976年 | 15篇 |
1975年 | 12篇 |
1974年 | 9篇 |
1970年 | 10篇 |
排序方式: 共有2049条查询结果,搜索用时 406 毫秒
11.
Calciphylaxis – a topical overview 总被引:3,自引:0,他引:3
G Arseculeratne† AT Evans‡ SM Morley† 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):493-502
'Calciphylaxis', a calcification syndrome associated with ischaemic cutaneous necrosis, is acquired naturally in humans in disease states. It is a life and limb-threatening complication, usually observed in patients with renal disease and secondary hyperparathyroidism, but known to occur in the absence of renal or parathyroid disease. The reported mortality rate, which ranges from 60-80%, relates to wound infection, sepsis and organ failure. It is a small-vessel vasculopathy, which is estimated to occur in about 4% of haemodialysis patients. Clinically, violaceous, reticulate areas of cutaneous necrosis and eschar may be evident, particularly in the extremities. In addition to the clinical picture, a raised calcium phosphorous product, an elevated parathyroid hormone level, radiographic evidence of vessel and soft-tissue calcification and the finding of mural calcification affecting small arteries and arterioles on histopathology help to confirm the diagnosis of this entity which generally has a poor prognosis. A high index of suspicion and an active multidisciplinary management approach, with rigorous attention to wound care and prevention of sepsis, are vital in the management of these patients. In this overview, we discuss the pathophysiology, clinical features and associations, risk factors, diagnosis and management issues relating to calciphylaxis. 相似文献
12.
Bastiaan R Klarenbeek Alexander AFA Veenhof Elly SM de Lange Willem A Bemelman Roberto Bergamaschi Piet Heres Antonio M Lacy Wim T van den Broek Donald L van der Peet Miguel A Cuesta 《BMC surgery》2007,7(1):16
Backround
Diverticulosis is a common disease in the western society with an incidence of 33–66%. 10–25% of these patients will develop diverticulitis. In order to prevent a high-risk acute operation it is advised to perform elective sigmoid resection after two episodes of diverticulitis in the elderly patient or after one episode in the younger (< 50 years) patient. Open sigmoid resection is still the gold standard, but laparoscopic colon resections seem to have certain advantages over open procedures. On the other hand, a double blind investigation has never been performed. The Sigma-trial is designed to evaluate the presumed advantages of laparoscopic over open sigmoid resections in patients with symptomatic diverticulitis. 相似文献13.
14.
15.
16.
Bonnie B. Asch Harold L. Asch Daniel L. Stoler Garth R. Anderson 《International journal of cancer. Journal international du cancer》1993,54(5):813-819
Of the several families of endogenous retrovirus-like elements present in the mouse genome, only mouse mammary tumor virus has been analyzed for its role in mammary carcino-genesis. Very little is known about the expression and activities of other retro-elements in normal and malignant mammary epithelium. We have begun investigating the possible involvement of the 3 retrotransposons, intracisternal A particles (IAPs), murine-leukemia-virus-related (MuLVr) elements, and VL30 sequences, in neoplastic progression of the mammary gland in BALB/c mice. The purpose of the present study was to determine which of these elements was active in primary mammary carcinomas induced by chemical, hormonal and viral agents. Each of these cancers had aberrant expression of at least one of the latter retrovirus-like components. IAP and/or MuLVr sequences were over-expressed 3 to 100-fold in most of the tumors as compared with normal mammary tissue, whereas VL30 expression was markedly decreased by 5- to 35-fold in almost all of the neoplasms. Our results thus demonstrate that substantial changes in the expression of one or more of these 3 families of endogenous retrotransposons are triggered during mouse mammary tumorigenesis, regardless of etiology. Direct involvement of lAPs and MuLVr elements in neoplastic progression by transposition and insertional mutagenesis in the genome of several hematopoietic cell types has already been demonstrated. Their elevated expression in many mammary carcinomas suggests that these retrotransposons may also be potential participants in some pathways of mouse mammary carcinogenesis. 相似文献
17.
18.
Korthuis PT Asch SM Anaya HD Morgenstern H Goetz MB Yano EM Rubenstein LV Lee ML Bozzette SA 《Journal of acquired immune deficiency syndromes (1999)》2004,35(3):253-260
BACKGROUND: Lipid screening is recommended for patients taking protease inhibitors (PIs). METHODS: We examined data from the Veterans Administration Immunology Case Registry to assess lipid screening among HIV-infected veterans who received PIs for at least 6 consecutive months during 1999 and 2001. We estimated crude and adjusted associations between lipid screening and patient characteristics (age, gender, HIV exposure, and race/ethnicity), comorbidities (AIDS, cardiovascular disease, diabetes, hypertension, smoking, and hyperlipidemia), and facility characteristics (urban location, case management, guidelines, and quality improvement programs). RESULTS: Among 4065 patients on PIs, clinicians screened 2395 (59%) for lipids within 6 months of initiating treatment. Adjusting for patient characteristics, comorbidities, facility traits, and clustering, lipid screening was more common among patients who were cared for in urban areas (relative risk [RR] = 1.3, confidence limits: 1.0-1.5), diabetic (RR = 1.2, confidence limits: 1.1-1.3), or previously hyperlipidemic (RR = 1.4, confidence limits: 1.3-1.5) and less common among patients with a history of intravenous drug use (IVDU) (RR = 0.90, confidence limits: 0.79-1.0) or unknown HIV risk (RR = 0.85, confidence limits: 0.75-0.95). CONCLUSIONS: Six in 10 patients taking PIs receive lipid screening within 6 months of PI use. Systemic interventions to improve overall HIV quality of care should also address lipid screening, particularly among patients with unknown or IVDU HIV risk and those cared for in nonurban areas. 相似文献
19.
20.
Solorio MR Asch SM Globe D Cunningham WE 《Journal of the National Medical Association》2002,94(7):581-589
PURPOSE: To examine satisfaction with access to health care in two populations, one with HIV and one with TB, and examine the effect of having a regular doctor and sociodemographic characteristics. DESIGN: Cross-Sectional survey. PATIENTS: A sample of HIV inpatients hospitalized at seven Los Angeles sites (N = 217) and TB outpatients chosen randomly from the Los Angeles County TB Registry Census (N = 313). ANALYSIS: We performed bivariate and multivariate regression analyses of satisfaction with access to care on gender, race/ethnicity, age, education, income, insurance, and having a regular doctor. MAIN OUTCOME MEASURES: A six-item scale of satisfaction with access to care (range 0-100; Cronbach's alpha 0.87). RESULTS: The mean satisfaction with access score for the HIV sample was significantly lower than the TB sample (53.5 vs. 61.2, p<0.001). The HIV sample multivariate analysis (including all the variables) showed that increasing age (p<0.021 and having a regular doctor (p<0.002) were associated with better access, and that low income (p<0.005) was associated with poor access. In the TB sample analysis, only increasing age was associated with better satisfaction with access to care (p< 0.01). CONCLUSION: HIV patients receiving care in the private sector reported less satisfaction with access to care compared to TB patients receiving care in the public health sector. The traditional factors of socio-economic status and having a regular doctor were associated with satisfaction with access-to-care in the HIV sample but not the TB sample. Our findings suggest that certain characteristics of the TB public health programs may explain these differences and suggests that, perhaps, the existence of a similar public health program for vulnerable low-income populations with HIV would improve their satisfaction with access, as well. 相似文献