全文获取类型
收费全文 | 1751篇 |
免费 | 134篇 |
国内免费 | 96篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 82篇 |
妇产科学 | 64篇 |
基础医学 | 165篇 |
口腔科学 | 70篇 |
临床医学 | 222篇 |
内科学 | 504篇 |
皮肤病学 | 14篇 |
神经病学 | 102篇 |
特种医学 | 150篇 |
外科学 | 176篇 |
综合类 | 68篇 |
预防医学 | 114篇 |
眼科学 | 29篇 |
药学 | 134篇 |
中国医学 | 1篇 |
肿瘤学 | 83篇 |
出版年
2023年 | 13篇 |
2022年 | 11篇 |
2021年 | 25篇 |
2020年 | 22篇 |
2019年 | 33篇 |
2018年 | 26篇 |
2017年 | 18篇 |
2016年 | 22篇 |
2015年 | 42篇 |
2014年 | 50篇 |
2013年 | 58篇 |
2012年 | 65篇 |
2011年 | 103篇 |
2010年 | 74篇 |
2009年 | 64篇 |
2008年 | 64篇 |
2007年 | 100篇 |
2006年 | 69篇 |
2005年 | 77篇 |
2004年 | 71篇 |
2003年 | 52篇 |
2002年 | 42篇 |
2001年 | 44篇 |
2000年 | 39篇 |
1999年 | 46篇 |
1998年 | 56篇 |
1997年 | 48篇 |
1996年 | 35篇 |
1995年 | 34篇 |
1994年 | 39篇 |
1993年 | 48篇 |
1992年 | 33篇 |
1991年 | 34篇 |
1990年 | 35篇 |
1989年 | 44篇 |
1988年 | 43篇 |
1987年 | 39篇 |
1986年 | 36篇 |
1985年 | 32篇 |
1984年 | 23篇 |
1983年 | 14篇 |
1982年 | 18篇 |
1980年 | 14篇 |
1979年 | 21篇 |
1978年 | 8篇 |
1977年 | 12篇 |
1975年 | 9篇 |
1973年 | 10篇 |
1970年 | 8篇 |
1966年 | 10篇 |
排序方式: 共有1981条查询结果,搜索用时 348 毫秒
31.
32.
33.
34.
35.
36.
Critically ill patients frequently have hyperglycemia. This event may reflect severe stress with an imbalance between anabolic hormones and catabolic hormones. Alternatively, it may reflect alterations in either insulin levels or insulin function. Insulin is a pleiotropic hormone with multiple important metabolic effects. In patients with sepsis, insulin levels are increased but insulin sensitivity is decreased. However, there is variability in insulin sensitivity, and this creates variability in glucose levels and insulin requirements and increases the frequency of hypo- and hyperglycemia. The factors that influence insulin sensitivity are complex and include inhibition of tyrosine kinase activity of the beta subunit, increased proteolytic activity resulting in loss of receptors from the plasma membrane, and possibly the transfer of insulin receptors into the nucleus where they bind to gene promoters. Better understanding of the role of insulin in critically ill patients requires prospective studies measuring insulin levels in various patient groups and the development of a simple measure of insulin sensitivity. 相似文献
37.
Elizabeth D. Ballard Níall Lally Allison C. Nugent Maura L. Furey David A. Luckenbaugh Carlos A. Zarate Jr 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(1)
Background:
The neural correlates of suicidal ideation and its reduction after treatment are unknown. We hypothesized that increased regional cerebral glucose metabolism in the infralimbic cortex (Brodmann area 25), amygdala, and subgenual anterior cingulate cortex would be associated with suicidal ideation and its reduction after ketamine infusion.Methods:
Medication-free patients (n=19) with treatment-resistant major depressive disorder underwent positron emission tomography imaging at baseline and 230 minutes after an open-label ketamine infusion (0.5mg/kg for 40 minutes).Results:
Baseline suicidal ideation and regional cerebral glucose metabolism in the infralimbic cortex were significantly correlated (r=.59, P=.007); but not overall mood scores (r=−.07, P=.79). Reductions in suicidal ideation after ketamine infusion were correlated with decreased regional cerebral glucose metabolism in the infralimbic cortex (r=.54, P=.02). Metabolism in other areas of interest was not significantly correlated with suicidal ideation or depression.Conclusion:
The infralimbic cortex may be implicated in suicidal ideation. 相似文献38.
Stacee M. Lerret Marianne E. Weiss Gail L. Stendahl Shelley Chapman Jerome Menendez Laurel Williams Michelle L. Nadler Katie Neighbors Katie Amsden Yumei Cao Melodee Nugent Estella M. Alonso Pippa Simpson 《Pediatric transplantation》2015,19(1):118-129
Pediatric SOT recipients are medically fragile and present with complex care issues requiring high‐level management at home. Parents of hospitalized children have reported inadequate preparation for discharge, resulting in problems transitioning from hospital to home and independently self‐managing their child's complex care needs. The aim of this study was to investigate factors associated with the transition from hospital to home and chronic illness care for parents of heart, kidney, liver, lung, or multivisceral recipients. Fifty‐one parents from five pediatric transplant centers completed questionnaires on the day of hospital discharge and telephone interviews at three wk, three months, and six months following discharge from the hospital. Care coordination (p = 0.02) and quality of discharge teaching (p < 0.01) was significantly associated with parent readiness for discharge. Readiness for hospital discharge was subsequently significantly associated with post‐discharge coping difficulty (p = 0.02) at three wk, adherence with medication administration (p = 0.03) at three months, and post‐discharge coping difficulty (p = 0.04) and family management (p = 0.02) at six months post‐discharge. The results underscore the important aspect of education and care coordination in preparing patients and families to successfully self‐manage after hospital discharge. Assessing parental readiness for hospital discharge is another critical component for identifying risk of difficulties in managing post‐discharge care. 相似文献
39.
K. P. Nugent M.S. F.R.C.S. A. D. Spigelman F.R.A.C.S. F.R.C.S. Mr. R. K. S. Phillips M.S. F.R.C.S. 《Diseases of the colon and rectum》1996,39(6):659-662
BACKGROUND: Recent work has demonstrated a correlation between frequency of aspirin ingestion and colorectal cancer prevention. Sulindac, another nonsteroidal anti-inflammatory drug (NSAID), has been shown to cause polyp regression and a fall in cell proliferation in patients with familial adenomatous polyposis, who are destined to develop colorectal cancer unless the colon is removed. However, the mode of action of NSAIDs in colorectal carcinogenesis prevention remains to be determined, although a prostaglandin-mediated mechanism seems likely. METHODS: Rectal or duodenal biopsies from 20 patients with familial adenomatous polyposis, who had been randomized to sulindac or placebo, were analyzed for prostaglandin (PG) E2 and E2α levels before and after treatment. RESULTS: A significant fall in prostaglandin E2 and E2α (P=0.0096; PGE2, P=0.036; PGF2α Spearman's rank correlation). CONCLUSIONS: Nonsteroidal antiinflammatory drugs may prevent colorectal cancer by their inhibition of prostaglandin synthesis. Prostaglandins may be implicated in carcinogenesis through an increase in cell proliferation, through immunosuppression, by increasing neovascularization, or via a mutagenic effect. 相似文献
40.
Joint haemorrhage and subsequent haemophilic arthropathy are significant complications in haemophilia. The pathophysiology involves inflammation and angiogenesis. Cyclooxygenase-2 (COX-2) inhibitors are anti-inflammatory agents, which have potent anti-inflammatory, anti-angiogenic and analgesic properties yet do not affect platelet function in the manner of traditional non-steroidal anti-inflammatory drugs. These properties make such agents potentially useful as adjunctive therapy in haemophilia. There is only one prior report describing rofecoxib treatment in a single haemophilia patient. Our objectives were to determine the safety and efficacy of rofecoxib in treating acute haemarthrosis, chronic synovitis, target joints and pain. We conducted a retrospective medical record review of patients treated with rofecoxib for acute haemarthrosis, chronic synovitis, target joint or pain. The safety and efficacy of rofecoxib treatment were determined based on subjective patient reports and physical examinations during follow-up clinic visits. A total of 28 patients between 3 and 37 years of age were treated for a total of 42 courses of rofecoxib treatment. All courses were evaluated for safety and 31 for efficacy. Rofecoxib was used for eight acute haemarthrosis, four target joints, seven cases of synovitis and 12 episodes of pain. Efficacy was demonstrated particularly for chronic synovitis and pain and no serious adverse events occurred. This is the largest study to date evaluating COX-2 inhibitors as adjunctive therapy in haemophilia and suggests that these agents may be an important adjunctive therapy in the management of haemophilia. 相似文献