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Objective and design
TNF-α neutralization is associated with increased mortality in mouse cecal ligation puncture (CLP) models. AZD9773 is an ovine polyclonal human TNF-α immune Fab, with pharmacological properties that differ from previously studied anti-TNF-α agents. We explored the safety and efficacy of therapeutically administered AZD9773 in mouse CLP sepsis.Methods
A moderate/severe-grade CLP model resulting in 20–30 % 5-day survival and a mild-grade CLP model resulting in ~70 % 5-day survival were established in human TNF-α transgene/murine TNF null (Tg1278/?/?) mice.Treatment
Mice received saline resuscitation and imipenem administration every 12 h (0–72 h post-CLP). AZD9773 (or DigiFab control) was dosed 24, 36, 48 and 60 h post-CLP.Results
Therapeutic dosing of AZD9773 in moderate/severe-grade CLP resulted in significantly increased survival (>70 %) compared with DigiFab (27 %, P < 0.05). Therapeutic dosing of AZD9773 in mild-grade CLP did not significantly affect survival outcome compared with DigiFab or imipenem alone (~60–70 % survival).Conclusions
These data demonstrate that TNF-α neutralization can improve survival in moderate/severe CLP sepsis. TNF-α suppression in mild-grade models was not associated with survival benefit and did not increase 5-day mortality. These findings suggest that therapeutic benefit following TNF-α attenuation in models of sepsis may depend on model severity. 相似文献Aims/hypothesis
The Leicester Practice Risk Score (LPRS) is a tool for identifying those at high risk of either impaired glucose regulation (IGR), defined as impaired glucose tolerance and/or impaired fasting glucose, or type 2 diabetes from routine primary care data. The aim of this study was to determine the yield from the LPRS when applied in two diabetes prevention trials.Methods
Let’s Prevent Diabetes (LPD) and Walking Away from Diabetes (WAD) studies used the LPRS to identify people at risk of IGR or type 2 diabetes from 54 general practices. The top 10% at risk within each practice were invited for screening using a 75 g OGTT. The response rate to the invitation and the prevalence of IGR and/or type 2 diabetes in each study were calculated.Results
Of those invited 19.2% (n?=?3,449) in LPD and 22.1% (n?=?833) in WAD attended. Of those screened for LPD 25.5% (95% CI 24.1, 27.0) had IGR and 4.5% (95% CI 3.8, 5.2) had type 2 diabetes, giving a prevalence of any abnormal glucose tolerance of 30.1% (95% CI 28.5, 31.6). Comparable rates were seen for the WAD study: IGR 26.5% (95% CI 23.5, 29.5), type 2 diabetes 3.0% (95% CI 1.8, 4.2) and IGR/type 2 diabetes 29.5% (95% CI 26.4, 32.6).Conclusions/interpretation
Using the LPRS identifies a high yield of people with abnormal glucose tolerance, significantly higher than those seen in a population screening programme in the same locality. The LPRS is an inexpensive and simple way of targeting screening programmes at those with the highest risk. 相似文献Background
Human induced pluripotent stem cells offer perspectives for cell therapy and research models for diseases. We applied this approach to the normal and pathological erythroid differentiation model by establishing induced pluripotent stem cells from normal and homozygous sickle cell disease donors.Design and Methods
We addressed the question as to whether these cells can reach complete erythroid terminal maturation notably with a complete switch from fetal to adult hemoglobin. Sickle cell disease induced pluripotent stem cells were differentiated in vitro into red blood cells and characterized for their terminal maturation in terms of hemoglobin content, oxygen transport capacity, deformability, sickling and adherence. Nucleated erythroblast populations generated from normal and pathological induced pluripotent stem cells were then injected into non-obese diabetic severe combined immunodeficiency mice to follow the in vivo hemoglobin maturation.Results
We observed that in vitro erythroid differentiation results in predominance of fetal hemoglobin which rescues the functionality of red blood cells in the pathological model of sickle cell disease. We observed, in vivo, the switch from fetal to adult hemoglobin after infusion of nucleated erythroid precursors derived from either normal or pathological induced pluripotent stem cells into mice.Conclusions
These results demonstrate that human induced pluripotent stem cells: i) can achieve complete terminal erythroid maturation, in vitro in terms of nucleus expulsion and in vivo in terms of hemoglobin maturation; and ii) open the way to generation of functionally corrected red blood cells from sickle cell disease induced pluripotent stem cells, without any genetic modification or drug treatment.Key words: human induced pluripotent stem cells, terminal maturation, erythropoietic differentiation 相似文献Methods: A cross-sectional survey of 196 family caregivers (CGs) of people with dementia (CGs) was conducted to determine the factor structure of a SEQCFC of people with dementia. Following factor analyses, preliminary testing was performed, including internal consistency, 4-week test-retest reliability, and construct and convergent validity.
Results: Factor analyses with direct oblimin rotation were performed. Eight items were removed and five subscales (self-efficacy for gathering information about treatment, symptoms and health care; obtaining support; responding to behaviour disturbances; managing household, personal and medical care; and managing distress associated with caregiving) were identified. The Cronbach's alpha coefficients for the whole scale and for each subscale were all over 0.80. The 4-week test-retest reliabilities for the whole scale and for each subscale ranged from 0.64 to 0.85. The convergent validity was acceptable.
Conclusions: Evidence for the preliminary testing of the SEQCFC was encouraging. A future follow-up study using confirmatory factor analysis with a new sample from different recruitment centres in Shanghai will be conducted. Future psychometric property testings of the questionnaire will be required for CGs from other regions of mainland China. 相似文献