全文获取类型
收费全文 | 1341370篇 |
免费 | 100521篇 |
国内免费 | 4281篇 |
专业分类
耳鼻咽喉 | 16825篇 |
儿科学 | 43802篇 |
妇产科学 | 36555篇 |
基础医学 | 198521篇 |
口腔科学 | 35940篇 |
临床医学 | 130810篇 |
内科学 | 259021篇 |
皮肤病学 | 26444篇 |
神经病学 | 112549篇 |
特种医学 | 48266篇 |
外国民族医学 | 366篇 |
外科学 | 184503篇 |
综合类 | 28835篇 |
现状与发展 | 1篇 |
一般理论 | 469篇 |
预防医学 | 115218篇 |
眼科学 | 29059篇 |
药学 | 99290篇 |
6篇 | |
中国医学 | 3169篇 |
肿瘤学 | 76523篇 |
出版年
2021年 | 11021篇 |
2019年 | 11754篇 |
2018年 | 16444篇 |
2017年 | 12401篇 |
2016年 | 13359篇 |
2015年 | 15329篇 |
2014年 | 21014篇 |
2013年 | 32382篇 |
2012年 | 44726篇 |
2011年 | 47362篇 |
2010年 | 27349篇 |
2009年 | 25171篇 |
2008年 | 43161篇 |
2007年 | 45502篇 |
2006年 | 45622篇 |
2005年 | 44025篇 |
2004年 | 41979篇 |
2003年 | 39909篇 |
2002年 | 38634篇 |
2001年 | 60880篇 |
2000年 | 62540篇 |
1999年 | 52332篇 |
1998年 | 14652篇 |
1997年 | 13320篇 |
1996年 | 13164篇 |
1995年 | 12503篇 |
1994年 | 11653篇 |
1993年 | 10953篇 |
1992年 | 41586篇 |
1991年 | 40780篇 |
1990年 | 39455篇 |
1989年 | 37355篇 |
1988年 | 34605篇 |
1987年 | 33704篇 |
1986年 | 32157篇 |
1985年 | 30653篇 |
1984年 | 23052篇 |
1983年 | 19600篇 |
1982年 | 11769篇 |
1979年 | 20814篇 |
1978年 | 14828篇 |
1977年 | 12071篇 |
1976年 | 11880篇 |
1975年 | 12115篇 |
1974年 | 14809篇 |
1973年 | 14475篇 |
1972年 | 13359篇 |
1971年 | 12418篇 |
1970年 | 11485篇 |
1969年 | 10411篇 |
排序方式: 共有10000条查询结果,搜索用时 11 毫秒
61.
62.
Claire M Rickard Brigit L Roberts Jonathon Foote Matthew R McGrail 《Dimensions of critical care nursing》2006,25(5):234-242
Research coordinators in intensive care are a growing specialty about which little is known. This cross-sectional study surveyed the Australia and New Zealand Intensive Care Research Coordinators' Group (n = 49) regarding demographics, education, employment history, job structure, and role content. Most research coordinators were highly qualified and experienced nurses who undertake pharmaceutical trials, multicenter projects, departmental medical and nursing research, audits and data registries, and their own projects. 相似文献
63.
64.
A Sharma H L Goh N Asokananthan A Bakker G A Stewart H W Mitchell 《The European respiratory journal》2006,27(1):20-28
Mucosal trypsin, a protease-activated receptor (PAR) stimulant, may have an endogenous bronchoprotective role on airway smooth muscle. To test this possibility the effects of lumenal trypsin on airway tone in segments of pig bronchus were tested. Bronchial segments from pigs were mounted in an organ chamber containing Kreb's solution. Contractions were assessed from isovolumetric lumen pressure induced by acetylcholine (ACh) or carbachol added to the adventitia. Trypsin, added to the airway lumen (300 microg x mL(-1)), had no immediate effect on smooth muscle tone but suppressed ACh-induced contractions after 60 min, for at least 3 h. Synthetic activating peptides (AP) for PAR1, PAR2 or PAR3 were without effect, but PAR4 AP caused rapid, weak suppression of contractions. Lumenal thrombin was without effect and did not prevent the effects of trypsin. Effects of trypsin were reduced by N(omega)-nitro-L-arginine methyl ester but not indomethacin. Trypsin, thrombin and PAR4 AP released prostaglandin E2. Adventitially, trypsin, thrombin and PAR4 AP (but not PAR2 AP) relaxed carbachol-toned airways after <3 min. The findings of this study show that trypsin causes delayed and persistent bronchoprotection by interacting with airway cells accessible from the lumen. The signalling mechanism may involve nitric oxide synthase but not prostanoids or protease-activated receptors. 相似文献
65.
AIMS: To establish all-cause and cause-specific death rates, and risk factors for mortality in insulin-treated diabetic individuals living in the province of Canterbury, New Zealand. METHODS: Insulin-treated diabetic subjects (n = 995) on the Canterbury Diabetes Registry were followed up over 15 years and vital status determined. Death rates were standardized and hazard regression was used to model the effects of demographic covariates on relative survival time. RESULTS: There were 419 deaths in 11 226.3 person-years of follow-up with a standardized mortality ratio (SMR) of 2.0 (95% confidence interval (CI) 1.8-2.2). Relative mortality was greatest for the group aged 0-29 years (SMR 3.0 (95% CI 2.4-3.7)). After controlling for diabetes duration and gender, a 10-year increment in age of onset was associated with a 33% decrease in relative hazard (95% CI 29-36%), indicating that excess mortality due to diabetes declines with rising age of onset. After controlling for age of onset and gender, each 10-year increment in duration of diabetes is associated with a 26% decrease in relative hazard (95% CI 24-29%), indicating that with longer survival the mortality hazard approaches the general population hazard. Relative mortalities were increased for cardiovascular, renal and respiratory disease, but not malignancy. Relative mortality from acute metabolic complications was increased in the subgroup with age of onset of diabetes < 30 years and requiring insulin within 1 year of diagnosis. CONCLUSIONS: Mortality rates are high for insulin-treated diabetic individuals relative to the general population. 相似文献
66.
Social phobia, fear of negative evaluation and harm avoidance. 总被引:1,自引:0,他引:1
M Faytout J Tignol J Swendsen D Grabot B Aouizerate J P Lépine 《European psychiatry》2007,22(2):75-79
This naturalistic, prospective investigation examined the role of fear of negative evaluation and the personality trait of harm avoidance in the anxiety levels of treated social phobia patients. One hundred and fifty-seven patients with DSM-IV social phobia were assessed before starting treatment and were then followed for up to two years. As expected, greater fear of negative evaluation and higher scores of harm avoidance were associated with greater anxiety at the 6 month follow-up, and harm avoidance remained a significant predictor at 24 months. However, no evidence was found for an interaction between the personality and cognitive variables examined. The findings are discussed in terms of the relative independence of these factors, as well as their potential implications for the treatment of this disorder. 相似文献
67.
P F Plouin D L Clement H Boccalon J Dormandy I Durand-Zaleski G Fowkes L Norgren T Brown 《International angiology》2003,22(4):333-339
Atherosclerotic renal artery stenosis (ARAS) may cause hypertension, progressive renal failure, and recurrent pulmonary edema. It typically occurs in high risk patients with coexistent vascular disease elsewhere. Most patients with ARAS are likely to die from coronary heart disease or stroke before end-stage renal failure occurs. Recent controlled trials have shown that most patients undergoing angioplasty to treat renovascular hypertension still need antihypertensive agents 6 or 12 months after the procedure. Nevertheless, the number of antihypertensive agents required to control blood pressure adequately is lower following angioplasty than for medication alone. Trials assessing the value of revascularization for preserving renal function or preventing clinical events are only in the early recruitment phase. Revascularization should be undertaken in patients with ARAS and resistant hypertension or heart failure, and probably in those with rapidly deteriorating renal function or with an increase in plasma creatinine levels during angiotensin-converting enzyme inhibition. With or without revascularization, medical therapy using antihypertensive, hypolipidemic and antiplatelet agents is necessary in almost all cases. 相似文献
68.
69.
Kevin L Taylor Rhonda K Oates Ron Grane Douglas W Leaman Ernest C Borden Daniel J Lindner 《Journal of interferon & cytokine research》2006,26(5):353-361
Interferon-alpha (IFN-alpha) has proved effective in the treatment of hemangiomas, hemangioblastomas, and Kaposi's sarcoma. To investigate the ability of IFNs to inhibit angiosarcoma, we used two transformed murine endothelial cell lines that form angiosarcomas in vivo. SVR and MS1-VEGF cell lines express oncogenic H-ras or vascular endothelial growth factor (VEGF), respectively. IFN-alpha1,8, which is active against murine and human cells, inhibited SVR and MS1-VEGF proliferation in vitro by 40% at 10(3) U/mL (p = 0.028). In vivo, IFN-alpha1,8 inhibited SVR tumor volume by 71% (p = 0.047) and MS1-VEGF volume by 79% (p = 0.003). Tumor-induced angiogenesis was decreased in SVR tumors by 52% (p = 0.005) and in MS1-VEGF tumors by 58% (p = 0.001). Sera from IFN-alpha1,8-treated mice bearing either SVR or MS1-VEGF tumors demonstrated a 5-fold increase in IP-10/CXCL10 (p = 0.001), an IFN-induced antiangiogenic protein. Both recombinant IP-10 and IFN-alpha1,8 inhibited human umbilical vein endothelial cell (HUVEC) vessel formation in the fibrin gel assay, a three-dimensional culture model of angiogenesis, by 56% at 25 ng/mL and 50% at 1.2 ng/mL, respectively (p < 0.001). An IP-10 blocking antibody restored vessel formation to 80% of untreated controls (p = 0.001). Given the magnitude of the in vivo response, these data suggested that the antitumor effects of IFN-alpha1,8 were likely mediated through angiogenesis inhibition rather than solely by direct inhibition of tumor cell proliferation. 相似文献
70.
Debra L. Roter Richard M. Frankel Judith A. Hall David Sluyter 《Journal of general internal medicine》2006,21(1):28-34
Relationship-centered care reflects both knowing and feeling: the knowledge that physician and patient bring from their respective domains of expertise, and the physician’s and patient’s experience, expression, and perception of emotions during the medical encounter. These processes are conveyed and reciprocated in the care process through verbal and nonverbal communication. We suggest that the emotional context of care is especially related to nonverbal communication and that emotion-related communication skills, including sending and receiving nonverbal messages and emotional self-awareness, are critical elements of high-quality care. Although nonverbal behavior has received far less study than other care processes, the current review argues that it holds significance for the therapeutic relationship and influences important outcomes including satisfaction, adherence, and clinical outcomes of care. 相似文献