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1.
目的:建立一种简单、经济、高效地培养恒河猴外周血单核巨噬细胞(monocyte-derived macrophage,MDM)的方法。方法:用肝素钠抗凝管采集健康成年中国恒河猴(Macaca mulatta)全血,密度梯度离心法分离外周血单核细胞(peripheral blood mononuclear cells, PBMCs)。同时用无抗凝剂采血管采集同一只猴外周血,自凝后分离血清。将猴PBMCs置于CELLBIND Surface的96孔(0.8×106个细胞/孔)或48孔培养板(3×106个细胞/孔)中,用含不同百分比的猴自体血清或胎牛血清(fetal calf serum,FCS)的RPMI 1640培养液培养24h后洗弃未贴壁细胞,加入含有猴自体血清或FCS的新鲜培养基继续培养7天后观察细胞形态学。分化良好的猴单核巨噬细胞贴壁能力强,占据板底大部分区域。胞体形态多样,多数呈长梭形。用巨噬细胞标记受体(CD14)抗体染色判断细胞纯度。并用细菌内毒素(LPS)刺激分化的巨噬细胞,检测巨噬细胞炎性因子的表达。此外,用猴艾滋病毒(SIVmac17E-Br、SIVmac251)和人-猴嵌合体艾滋病毒(SHIV KU-1)感染分化良好的猴巨噬细胞,检测病毒在猴巨噬细胞中的复制。结果:在含2%猴自体血清的RPMI 1640培养条件下,大多数(>85%)猴单核细胞能在24h内贴壁,体外分化5-7天后,猴巨噬细胞纯度大于96%。相比而言,含较高浓度(4%,8%或10%)猴自体血清或FCS的RPMI 1640 培养基对猴单核细胞的贴壁和分化作用较差。分化良好的猴巨噬细胞对LPS刺激敏感,可产生多种巨噬细胞炎性因子。此外,这些细胞对SIV或SHIV均易感,产生感染性病毒。结论:含2%猴自体血清的RPMI 1640培养基适于原代猴单核细胞的贴壁和分化。该方法简单、花费少,无需生长因子,且分化效果好,是培养猴艾滋病毒及开展相关免疫学实验的重要手段。  相似文献   
2.
目的 研究揭示白毛黑眼兔黑眼性状的遗传模式。方法 选取具有黑眼突变性状的白毛黑眼兔与其背景品系日本大耳白兔进行杂交,构建6个两代杂交家系。对杂交产生的F1代和F2代个体虹膜颜色性状的观察和统计,并应用遗传数理统计方法中常用的分离分析进行遗传模式探讨。结果 χ^2检验显示,杂交实验所得虹膜颜色分布的观察值与常染色体单基因显性遗传模式的期望值无显著差异(P>0.05),与常染色体隐性遗传及伴性遗传模式的期望值有显著差异(P<0.05)结论 白毛黑眼兔的黑眼突变是由常染色体上单个基因的变异造成的显性性状。  相似文献   
3.
实验性自身免疫性脑脊髓炎(experimental autoimmune encephalomyelitis,EAE)是多发性硬化的实验动物模型,经过近2个多世纪的发展,已可以在猴、大鼠、小鼠等动物制备EAE模型,在同一种品系动物采用不同免疫抗原制备的EAE模型在敏感性和临床特点具有多样性。本研究就EAE的发展史和目前不同品系实验动物、不同抗原制备EAE模型的特点做一述评,对未来EAE模型的发展前景进行探讨。  相似文献   
4.
Two strains of Cryptococcus neoformans (PU 66 and PU112) were simultaneously isolated from a patient with systemic lupus erythematosus. We aimed to trace the source of the mixed infections. Multi‐locus sequence typing (MLST) and the DiversiLab system analyses were performed on the 2 clinical and 23 environmental C. neoformans from pigeon droppings, 11 from the home (H1) the patient visited, 12 from another home (H2) as control. All the strains were uniformly genotyped as C. neoformans var. grubii VNI. Clinical strain PU66 and all the H1 isolates had the same sequence type (ST) – ST5, while for PU112 a new ST was observed – ST265. However, there was only one single base of 7 MLST loci difference between PU66 and PU112. Sequence types of the H2 strains were ST31 and ST297. DiversiLab analysis showed that strain similarity between the two clinical strains was 96.7%. In relation to environmental samples, the highest strain similarity (99.3%) was observed for PU66 and PU70 (H1). However, none of the environmental isolates had similarity over 98.6% comparing to PU112. One source of the mixed infections has been detected, but another needs further investigation.  相似文献   
5.
In vivo T‐cell depletion, using alemtuzumab therapy prior to SCT, can reduce the incidence of GVHD. This treatment has a potential to delay immune reconstitution resulting in increased morbidity due to viral illnesses. We retrospectively analyzed data on all pediatric patients with non‐malignant disorders who received alemtuzumab‐based conditioning regimens in our center over the last 10 yr (n = 91). Our data show an OS of 91.2%. The incidence of acute (grade 2–4) GVHD was 18.7% and that of chronic GVHD 5.5%. Viremia due to adenovirus, EBV and CMV was seen in 19.8%, 64.8% and 39.6% patients, respectively, with only two deaths attributed to viral infection (adenovirus). Chimerism level at three month was predictive of graft outcome. Nine patients, who had graft failure after first SCT, were salvaged with a second SCT using RIC and same donor (if available). Based on these results, we conclude that the use of in vivo T‐cell depletion is safe, achieves good chimerism and does not lead to increased morbidity and mortality due to viral infections. It is associated with a reduced incidence of chronic GVHD.  相似文献   
6.
Cell adhesion molecule cadherins play important roles in both development and maintenance of adult structures. Most studies on cadherin expression have been carried out in developing organisms, but information on cadherin distribution in adult vertebrate brains is limited. In this study we used in situ hybridization to examine mRNA expression of three cadherins, protocadherin‐19, protocadherin‐17, and cadherin‐6 in adult zebrafish brain. Each cadherin exhibits a distinct expression pattern in the fish brain, with protocadherin‐19 and protocadherin‐17 showing much wider and stronger expression than that of cadherin‐6. Both protocadherin‐19 and protocadherin‐17‐expressing cells occur throughout the brain, with strong expression in the ventromedial telencephalon, periventricular regions of the thalamus and anterior hypothalamus, stratum periventriculare of the optic tectum, dorsal tegmental nucleus, granular regions of the cerebellar body and valvula, and superficial layers of the facial and vagal lobes. Numerous sensory structures (e.g., auditory, gustatory, lateral line, olfactory, and visual nuclei) and motor nuclei (e.g., oculomotor, trochlear, trigeminal motor, abducens, and vagal motor nuclei) contain protocadherin‐19 and/or protocadherin‐17‐expressing cell. Expression of these two protocadherins is similar in the ventromedial telencephalon, thalamus, hypothalamus, facial, and vagal lobes, but substantially different in the dorsolateral telencephalon, intermediate layers of the optic tectum, and cerebellar valvula. In contrast to the two protocadherins, cadherin‐6 expression is much weaker and limited in the adult fish brain. J. Comp. Neurol. 523:1419–1442, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
7.
This focussed narrative review examines neurobiological and psychophysiological evidence supporting a role for altered reward processes in the development and maintenance of anorexia nervosa (AN). In AN, there does not appear to be a generalised inability to experience reward. Rather, data suggest that a reluctance to gain weight leads to an aversive appraisal of food- and taste-related stimuli. As a result, cues compatible with this aberrant mode of thinking become rewarding for the individual. Evidence also suggests that attribution of motivational salience to such cues promotes anorectic behaviours. These findings are consistent with models in which interactions between cognition and reward are important in eliciting the anorectic “habit”. A model is proposed which is consistent with elements of other theoretical frameworks, but differs in that its emphasis is towards neural overlaps between AN and addiction. It is consistent with AN being a reward-based learned behaviour in which aberrant cognitions related to eating and shape alter functioning of central reward systems. It proposes that the primary neural problem responsible for the development, maintenance, and treatment resistance is centred in the striatal reward system. This helps shift the emphasis of aetiological models towards reward processing, particularly in the context of illness-compatible cues. Furthermore, it suggests that continuing to explore the utility and valued nature of AN in the patient's life would be a useful inclusion in treatment and prevention models.  相似文献   
8.
When one encounters a novel stimulus this sets off a cascade of brain responses, activating several neuromodulatory systems. As a consequence novelty has a wide range of effects on cognition; improving perception and action, increasing motivation, eliciting exploratory behavior, and promoting learning. Here, we review these benefits and how they may arise in the brain. We propose a framework that organizes novelty's effects on brain and cognition into three groups. First, novelty can transiently enhance perception. This effect is proposed to be mediated by novel stimuli activating the amygdala and enhancing early sensory processing. Second, novel stimuli can increase arousal, leading to short-lived effects on action in the first hundreds of milliseconds after presentation. We argue that these effects are related to deviance, rather than to novelty per se, and link them to activation of the locus-coeruleus norepinephrine system. Third, spatial novelty may trigger the dopaminergic mesolimbic system, promoting dopamine release in the hippocampus, having longer-lasting effects, up to tens of minutes, on motivation, reward processing, and learning and memory.  相似文献   
9.
The neuropsychopharmacological basis of fear‐ or panic‐related behavior has been the focus of several studies. Some mesencephalic tectum (MT) structures, such as the superior colliculus (SC) and dorsal periaqueductal gray matter (dPAG), are considered to be responsible for the control of defensive responses evoked during threatening situations. Furthermore, the pars reticulata of the substantia nigra (SNpr) sends inputs to the SC that can work as a sensory channel to MT neurons fundamental for the elaboration of defensive responses. The purpose of the present study was to investigate the role of striato‐nigral GABAergic inputs in the activity of nigro‐tectal outputs during the elaboration of defensive behavior using a GABAA receptor selective blockade in the MT of mice confronted pre‐treated with Bothrops alternatus. Mice with injections of physiological saline into the SNpr and treated with a GABAA receptor selective antagonist in the MT displayed an increase in panic‐related behavior, expressed by an increase in the duration of freezing, frequency of nonoriented escape and frequency of total escape responses during the confrontation with the snake. However, intra‐SNpr injections of cobalt chloride followed by MT injections of bicuculline caused a significant decrease in the duration of freezing and total escape responses. In addition, intra‐SNpr injections of lidocaine followed by MT injections of bicuculline caused an increase in panic‐related behavior. The results highlight the involvement of SNpr and MT structures in the organization of defensive behaviors and suggest an inhibitory control of striatonigral‐nigrotectal pathways during the elaboration of fear‐ and panic‐related behavior. Synapse 69:299–313, 2015 . © 2015 Wiley Periodicals, Inc.  相似文献   
10.
The high‐dimensional propensity score (hdPS) algorithm was proposed for automation of confounding adjustment in problems involving large healthcare databases. It has been evaluated in comparative effectiveness research (CER) with point treatments to handle baseline confounding through matching or covariance adjustment on the hdPS. In observational studies with time‐varying interventions, such hdPS approaches are often inadequate to handle time‐dependent confounding and selection bias. Inverse probability weighting (IPW) estimation to fit marginal structural models can adequately handle these biases under the fundamental assumption of no unmeasured confounders. Upholding of this assumption relies on the selection of an adequate set of covariates for bias adjustment. We describe the application and performance of the hdPS algorithm to improve covariate selection in CER with time‐varying interventions based on IPW estimation and explore stabilization of the resulting estimates using Super Learning. The evaluation is based on both the analysis of electronic health records data in a real‐world CER study of adults with type 2 diabetes and a simulation study. This report (i) establishes the feasibility of IPW estimation with the hdPS algorithm based on large electronic health records databases, (ii) demonstrates little impact on inferences when supplementing the set of expert‐selected covariates using the hdPS algorithm in a setting with extensive background knowledge, (iii) supports the application of the hdPS algorithm in discovery settings with little background knowledge or limited data availability, and (iv) motivates the application of Super Learning to stabilize effect estimates based on the hdPS algorithm. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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