全文获取类型
收费全文 | 2725篇 |
免费 | 279篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 62篇 |
妇产科学 | 65篇 |
基础医学 | 466篇 |
口腔科学 | 67篇 |
临床医学 | 258篇 |
内科学 | 462篇 |
皮肤病学 | 88篇 |
神经病学 | 478篇 |
特种医学 | 105篇 |
外科学 | 285篇 |
综合类 | 11篇 |
一般理论 | 2篇 |
预防医学 | 208篇 |
眼科学 | 52篇 |
药学 | 177篇 |
中国医学 | 7篇 |
肿瘤学 | 200篇 |
出版年
2024年 | 3篇 |
2023年 | 29篇 |
2022年 | 58篇 |
2021年 | 76篇 |
2020年 | 77篇 |
2019年 | 88篇 |
2018年 | 102篇 |
2017年 | 99篇 |
2016年 | 109篇 |
2015年 | 116篇 |
2014年 | 161篇 |
2013年 | 153篇 |
2012年 | 264篇 |
2011年 | 261篇 |
2010年 | 136篇 |
2009年 | 141篇 |
2008年 | 160篇 |
2007年 | 168篇 |
2006年 | 170篇 |
2005年 | 133篇 |
2004年 | 125篇 |
2003年 | 125篇 |
2002年 | 96篇 |
2001年 | 18篇 |
2000年 | 17篇 |
1999年 | 22篇 |
1998年 | 15篇 |
1997年 | 14篇 |
1996年 | 10篇 |
1995年 | 13篇 |
1994年 | 12篇 |
1993年 | 4篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1988年 | 6篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1983年 | 1篇 |
1980年 | 1篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1972年 | 2篇 |
1969年 | 1篇 |
排序方式: 共有3010条查询结果,搜索用时 15 毫秒
71.
B Sierra AB Pérez M Alvarez G García K Vogt E Aguirre K Schmolke HD Volk MG Guzmán 《The American journal of tropical medicine and hygiene》2012,87(3):538-547
Abstract. Secondary heterologous dengue infection is a risk factor for severe disease manifestations because of the immune-enhancement phenomenon. Succeeding clinical infections are seldom reported, and the clinical course of tertiary and quaternary dengue infections is not clear. Cuba represents a unique environment to study tertiary/quaternary dengue infections in a population with known clinical and serologic dengue markers and no dengue endemicity. We took advantage of this exceptional epidemiologic condition to study the effect of primary, secondary, tertiary, and quaternary dengue infection exposure on the expression of pro-inflammatory and regulatory cytokines, critical in dengue infection pathogenesis, by using a dengue infection ex vivo model. Whereas secondary exposure induced a high cytokine response, we found a significantly lower expression of tumor necrosis factor-α, interferon-γ, interleukin-10, and tumor growth factor-β after tertiary and quaternary infectious challenge. Significant differences in expression of the cytokines were seen between the dengue immune profiles, suggesting that the sequence in which the immune system encounters serotypes may be important in determining the nature of the immune response to subsequent infections. 相似文献
72.
73.
74.
We have identified a population of normal mouse LN cells, termed LN lymphoid progenitor (LNLP), resembling common lymphoid progenitor (CLP) in the bone marrow. LNLPs lack lineage markers and express CD127, low levels of CD117 (c-Kit), and Sca-1, but lack fms-related tyrosine kinase 3. They efficiently differentiate in vitro into natural killer (NK) cells and T cells, but not mature B cells. LNLPs injected into nonirradiated lymphopenic mice that have no LN develop into mostly splenic T cells with low numbers of NK cells and B cells. When injected into irradiated mice, they generate NK cells and T cells, but not B cells, in the LN. By contrast, bone marrow CLPs develop into mostly B cells with very small numbers of T and NK cells in recipients' spleen and LN. LNLPs have NK and T-cell potentials, but little B-cell potential, and they can develop into NK cells within the LN of normal mice, but their contribution to the T-cell lineage is unknown. 相似文献
75.
The uterus is an essential organ for reproduction in mammals that derives from the Müllerian duct. Despite the importance of the uterus for the fertility and health of women and their offspring, relatively little is known about the hormonal, cellular and molecular mechanisms that regulate development of the Müllerian duct and uterus. This review aims to summarize the hormonal, cellular and molecular mechanisms and pathways governing development of the Müllerian duct and uterus as well as highlight developmental programming effects of endocrine disruptor compounds. Organogenesis, morphogenesis, and functional differentiation of the uterus are complex, multifactorial processes. Disruption of uterine development in the fetus and neonate by genetic defects and exposure to endocrine disruptor compounds can cause infertility and cancer in the adult and their offspring via developmental programming. Clear conservation of some factors and pathways are observed between species; therefore, comparative biology is useful to identify candidate genes and pathways underlying congenital abnormalities in humans. 相似文献
76.
Posterior alien hand syndrome is a new addition to a poorly understood group of movement disorders. Historically, anatomical lesions causing uncontrolled limb movement and a feeling of foreignness were found to be located in the corpus callosum or frontal lobe. Recent case reports, however, demonstrate the typical symptoms of alien hand syndrome with lesions located in the parietal/occipital lobes. Disturbance of normal function in these regions tends to produce less complex motor activity, such as hand levitation, along with a sensory component characterized by feeling of estrangement. We discuss a patient who presented with unusual symptoms following an outpatient procedure and was found to have posterior alien hand syndrome. 相似文献
77.
Maria Wostrack Nora Sandow Peter Vajkoczy Bawarjan Schatlo Philippe Bijlenga Karl Schaller Victoria Kehl Kathrin Harmening Florian Ringel Yu-Mi Ryang Benjamin Friedrich Michael Stoffel Bernhard Meyer 《Acta neurochirurgica》2013,155(4):579-586
Background
Aneurysmal subarachnoid haemorrhage (SAH) WFNS grade V is commonly known to be associated with high mortality and a very poor prognosis for survivors. Therefore, maximal invasive therapy is frequently delayed until any spontaneous improvement with or without an external ventricular drainage occurs. The aim of the study was to verify possible predictive factors and the probability of a favourable outcome in maximally treated patients.Methods
One hundred and thirty-eight consecutive patients with WFNS grade V SAH were admitted between 03/2006 and 12/2010. Thirty-five patients died before aggressive therapy could proceed. One hundred and three patients received maximal treatment and were retrospectively evaluated. The outcome was assessed at discharge and in the follow-up with the Glasgow Outcome Scale. Univariate and multivariate linear regression models were performed to find predictors for an unfavourable outcome.Results
Despite treatment, early mortality was 30 % (n?=?31). At discharge, the rate of both vegetative and severely disabled patients was 27 % (n?=?28). Favourable outcome at discharge was observed in 16 % (n?=?16) of cases, whereas in the follow-up it rose to 26 % (n?=?27). Multivariate full model regression identified intraventricular haematoma (IVH) and increasing age as independently predictive for poor outcome.Conclusions
Despite treatment, initial mortality and severe disability remain high. Nevertheless, a favourable outcome was achieved in 26 % of aggressively treated patients, rendering the withdrawal of maximal therapy for WFNS grade V SAH patients unacceptable today. In cases of old patients with IVH, the indication for aggressive therapy should be put in place more carefully due to a very poor prognosis. 相似文献78.
79.
Gout affects 1% to 2% of the population, and the prevalence is increasing due to changes in diet and the ageing of the population.
Its development and risk factors have been explored frequently, and recommendations for the diagnosis and management of gout
implemented. Nevertheless, there is a lack of knowledge regarding the long-term impact on gouty patients. This systematic
review therefore evaluates the association between gout and all-cause as well as cardiovascular mortality. A systematic literature
search was performed, and seven long-term studies were ultimately analyzed. Six of them used multivariate regressions to assess
the adjusted mortality ratio in gouty patients with reference to patients without the disorder. Despite differences in study
designs, study populations, and definitions of gout, the results were consistent: There was an independent association between
gout and all-cause as well as cardiovascular mortality. Knowing that patients with gout are at risk emphasizes the need for
adequate care. 相似文献
80.
Hilty M Betsch BY B?gli-Stuber K Heiniger N Stadler M Küffer M Kronenberg A Rohrer C Aebi S Endimiani A Droz S Mühlemann K 《Clinical infectious diseases》2012,55(7):967-975
Background.?Studies about transmission rates of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae in hospitals and households are scarce. Methods.?Eighty-two index patients with new carriage of ESBL-producing Escherichia coli (ESBL-Ec; n?=?72) or ESBL-producing Klebsiella pneumoniae (ESBL-Kp; n?=?10) and their hospital (n?=?112) and household (n?=?96) contacts were studied prospectively from May 2008 through September 2010. Isolates were phenotypically and molecularly characterized (sequencing of bla genes, repetitive extragenic palindromic polymerase chain reaction, pulse-field gel electrophoresis, and multilocus sequence typing). Transmission was defined as carriage of a clonally-related ESBL producer with identical bla(ESBL) gene(s) in the index patient and his or her contact(s). Results.?CTX-M-15 was the most prevalent ESBL in ESBL-Ec (58%) and ESBL-Kp (70%) in the index patients. Twenty (28%) ESBL-Ec isolates were of the hyperepidemic clone ST131. In the hospital, transmission rates were 4.5% (ESBL-Ec) and 8.3% (ESBL-Kp) and the incidences of transmissions were 5.6 (Ec) and 13.9 (Kp) per 1000 exposure days, respectively. Incidence of ESBL-Kp hospital transmission was significantly higher than that of ESBL-Ec (P?.0001), despite implementation of infection control measures in 75% of ESBL-Kp index patients but only 22% of ESBL-Ec index patients. Detection of ESBL producers not linked to an index patient was as frequent (ESBL-Ec, 5.7%; ESBL-Kp, 16.7%) as nosocomial transmission events. In households, transmission rates were 23% for ESBL-Ec and 25% for ESBL-Kp. Conclusions.?Household outweighs nosocomial transmission of ESBL producers. The effect of hospital infection control measures may differ between different species and clones of ESBL producers. 相似文献