全文获取类型
收费全文 | 930881篇 |
免费 | 67587篇 |
国内免费 | 1341篇 |
专业分类
耳鼻咽喉 | 12959篇 |
儿科学 | 24371篇 |
妇产科学 | 23235篇 |
基础医学 | 132985篇 |
口腔科学 | 28241篇 |
临床医学 | 80542篇 |
内科学 | 183307篇 |
皮肤病学 | 19230篇 |
神经病学 | 72198篇 |
特种医学 | 36799篇 |
外国民族医学 | 79篇 |
外科学 | 152106篇 |
综合类 | 18042篇 |
现状与发展 | 1篇 |
一般理论 | 234篇 |
预防医学 | 61740篇 |
眼科学 | 21308篇 |
药学 | 72544篇 |
3篇 | |
中国医学 | 2164篇 |
肿瘤学 | 57721篇 |
出版年
2018年 | 8963篇 |
2017年 | 7031篇 |
2016年 | 7761篇 |
2015年 | 8862篇 |
2014年 | 11985篇 |
2013年 | 17504篇 |
2012年 | 24092篇 |
2011年 | 25050篇 |
2010年 | 14807篇 |
2009年 | 14277篇 |
2008年 | 24603篇 |
2007年 | 25717篇 |
2006年 | 26496篇 |
2005年 | 25450篇 |
2004年 | 24600篇 |
2003年 | 23633篇 |
2002年 | 23152篇 |
2001年 | 54732篇 |
2000年 | 56542篇 |
1999年 | 46952篇 |
1998年 | 10735篇 |
1997年 | 9470篇 |
1996年 | 9601篇 |
1995年 | 8928篇 |
1994年 | 8284篇 |
1993年 | 7597篇 |
1992年 | 35490篇 |
1991年 | 33915篇 |
1990年 | 32739篇 |
1989年 | 31877篇 |
1988年 | 28994篇 |
1987年 | 28251篇 |
1986年 | 26292篇 |
1985年 | 25145篇 |
1984年 | 17832篇 |
1983年 | 15143篇 |
1982年 | 7795篇 |
1981年 | 6774篇 |
1979年 | 15785篇 |
1978年 | 10598篇 |
1977年 | 9054篇 |
1976年 | 7872篇 |
1975年 | 8631篇 |
1974年 | 10467篇 |
1973年 | 9859篇 |
1972年 | 9358篇 |
1971年 | 8855篇 |
1970年 | 8426篇 |
1969年 | 7930篇 |
1968年 | 7202篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
181.
Salvage of a failed valgus osteotomy for nonunion
of an unstable pertrochanteric fracture is reported.
A valgus intertrochanteric osteotomy was performed for a
failed sliding hip screw fixation of an unstable
pertrochanteric fracture at another institution. Four months
following osteotomy, the fracture was still un-united with
two distal screws of the hip plate broken and a coxa vara
deformity. Reconstruction was performed with a nine-hole
95° angle blade plate and cancellous bone graft, because the
insufficient fixation of the distal fragment was considered to
be the main reason for failure. The osteotomy was healed at
six months post-surgery and the patient reported complete
resolution of symptoms. Intertrochanteric valgus osteotomy
is an effective procedure for mal-union and non-union of
pertrochanteric fracture but stable fixation is required for a
good result. The blade of the angle plate offers good purchase
of the proximal fragment and secures it under rotational
and bending stresses. We recommend that distal fragments
should be fixed with at least seven cortices for this
type of osteotomy. 相似文献
182.
目的:过去15年在慢性胰腺炎(CP)的内镜治疗中取得了巨大进展。然而,经内镜行胰腺内放置支架的价值还有争议。材料与方法:对98例(84例男性,14例女性,年龄49±12岁,极差23~83)有症状的CP患进行包括胰管内临时支架的内镜下介入治疗。将最后支架取出时作为内镜治疗的主要研究终点,96例患共随访了35±28个月(极差8d~111个月),对所有数据进行回顾性分析。结果:与其他的内镜下操作一样,共有358个支架放置在胰管内且留置了3±1个月(极差1d~11个月)。总的支架治疗时间是10±10个月(极差6d~49个月)。在有限的内镜治疗后的46±27个月(极差4~111个月)中,57例患不需要再次介入治疗,甚至2/3患没有更多的疼痛感。在22例需要外科治疗和17例需要再次内镜治疗的患中明显与继续摄入乙醇有关。结论:临时支架植入作为CP患内镜介入治疗的一部分有较高的技术含量和长期临床成功率,而且在相当多患中不需要二次治疗。禁止乙醇摄入明显有助于治疗效果的维持。 相似文献
183.
Mark W Woolrich Peter Chiarelli Daniel Gallichan Joanna Perthen Thomas T Liu 《Magnetic resonance in medicine》2006,56(4):891-906
The study of brain function using MRI relies on acquisition techniques that are sensitive to different aspects of the hemodynamic response contiguous to areas of neuronal activity. For this purpose different contrasts such as arterial spin labeling (ASL) and blood oxygenation level dependent (BOLD) functional MRI techniques have been developed to investigate cerebral blood flow (CBF) and blood oxygenation, respectively. Analysis of such data typically proceeds by separate, linear modeling of the appropriate CBF or BOLD time courses. In this work an approach is developed that provides simultaneous inference on hemodynamic changes via a nonlinear physiological model of ASL data acquired at multiple echo times. Importantly, this includes a significant contribution by changes in the static magnetization, M, to the ASL signal. Inference is carried out in a Bayesian framework. This is able to extract, from dual-echo ASL data, probabilistic estimates of percentage changes of CBF, R(2) (*), and the static magnetization, M. This approach provides increased sensitivity in inferring CBF changes and reduced contamination in inferring BOLD changes when compared with general linear model approaches on single-echo ASL data. We also consider how the static magnetization, M, might be related to changes in CBV by assuming the same mechanism for water exchange as in vascular space occupancy. 相似文献
184.
J Phua E S C Koay D Zhang L K Tai X L Boo K C Lim T K Lim 《The European respiratory journal》2006,28(4):695-702
Levels of the soluble form of the triggering receptor expressed on myeloid cells (sTREM)-1 are elevated in severe sepsis. However, it is not known whether sTREM-1 measurements can distinguish milder bacterial infections from noninfectious inflammation. The present authors studied whether serum sTREM-1 levels differ in community-acquired pneumonia, exacerbations of chronic obstructive pulmonary disease (COPD), asthma and controls, and whether sTREM-1 may be used as a surrogate marker for the need for antibiotics. Serum sTREM-1 levels in 150 patients with pneumonia, COPD and asthma exacerbations and 62 healthy controls were measured. Serum sTREM-1 levels were significantly elevated in pneumonia (median 295.2 ng x mL(-1)), COPD (280.3 ng x mL(-1)) and asthma exacerbations (184.0 ng x mL(-1)) compared with controls (83.1 ng x mL(-1)). Levels were higher in pneumonia and Anthonisen type 1 COPD exacerbations than in type 2 and 3 COPD and asthma exacerbations. The area under the receiver operating characteristics curve for sTREM-1 as a surrogate marker for the need for antibiotics was 0.77. Serum levels of the soluble form of the triggering receptor expressed on myeloid cells-1 were elevated predominantly in pneumonia and Anthonisen type 1 COPD exacerbations versus type 2 and 3 chronic obstructive pulmonary disease exacerbations, asthma and controls. Serum levels of the soluble form of the triggering receptor expressed on myeloid cells-1 has moderate but insufficient accuracy as a surrogate marker for the need for antibiotics in lower respiratory tract infections. 相似文献
185.
186.
Transplanting the Highly Sensitized Patient: The Emory Algorithm 总被引:4,自引:0,他引:4
R. A. Bray J. D. L. Nolen C. Larsen T. Pearson K. A. Newell K. Kokko A. Guasch P. Tso J. B. Mendel H. M. Gebel 《American journal of transplantation》2006,6(10):2307-2315
Renal transplant patients sensitized to HLA antigens comprise nearly one-third of the UNOS wait-list and receive 14% of deceased donor (DD) transplants, a rate half that of unsensitized patients. Between 1999 and 2003, we performed 492 adult renal transplants from DD; 120 patients (approximately 25%) had a panel reactive antibody (PRA) of >30%, with nearly half (n = 58) having a PRA of >80%. Our approach is based upon high-resolution solid-phase HLA antibody analysis to identify class I/II antibodies and a 'virtual crossmatch' to predict compatible donor/recipient combinations. Recipients are excluded from the United Network for Organ Sharing match run if donors possess unacceptable antigens. Thus, when sensitized patients appear on the match run, they have a high probability of a negative final crossmatch. Here, we describe our 5-year experience with this approach. Five-year graft survival ranged from 66% to 70% among unsensitized (n = 272), moderately sensitized (PRA < 30%, n = 100) and highly sensitized (>30% PRA; n = 120) patients, equal to the average national graft survival (65.7%). The application of this approach (the Emory Algorithm) provides a logical and systematic approach to improve the access of sensitized patients to DD organs and promote more equitable allocation to a highly disadvantaged group of patients awaiting renal transplantation. 相似文献
187.
188.
Patricia A Wilkosz Sachiko Miyahara Oscar L Lopez Steven T Dekosky Robert A Sweet 《The American journal of geriatric psychiatry》2006,14(4):352-360
BACKGROUND: Psychotic symptoms in Alzheimer disease (AD+P) identify a heritable phenotype associated with more rapid cognitive decline. The authors have proposed that AD+P is itself a composite of a misidentification and a paranoid subtype with increased cognitive impairment restricted to the misidentification type. Most prior studies of the clinical correlates of AD+P have been limited, however, by the inclusion of prevalent cases. METHODS: Subjects with possible or probable AD or mild cognitive impairment (MCI) without psychosis at study entry were assessed at the time of initial presentation and then annually. Psychotic symptoms were assessed using the CERAD Behavioral Rating Scale. Survival analyses used Cox proportional hazard models with time-dependent covariates to examine the predictors of psychosis onset. RESULTS: A total of 288 subjects completed at least one follow-up examination. Mean duration of follow-up was 22.1 months. The incidence of psychosis was 0.19 per person-year. Cognitive impairment was associated with onset of psychosis, largely as a result of its association with onset of the misidentification, but not the paranoid, subtype. Including psychotropic medication use in the model revealed an association of antidepressant use with the onset of psychosis. This latter association appeared to arise from an underlying association between depression and the risk of psychosis onset rather than from antidepressant treatment. CONCLUSION: These findings are consistent with the hypothesis that the misidentification and the paranoid subtypes each define a more biologically homogeneous group than AD+P as a whole. Further exploration of the relationship between depressive symptoms and psychosis in patients with AD is warranted. 相似文献
189.
190.
S. KATO N. MATSUKURA N. MATSUDA K. TSUKADA† Z. NAITO‡ & T. TAJIRI 《Alimentary pharmacology & therapeutics》2006,24(S4):278-284