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101.
A pilot study using capillary electrophoresis with mass spectrometry for the analysis of nucleotides in human erythrocytes is presented. Erythrocytes were incubated with 5-amino-4-imidazolecarboxamide riboside in order to mimic situation in defect of purine metabolism—AICA-ribosiduria. Characteristic AICA-ribotides together with normal nucleotides were separated by capillary electrophoresis in acetate buffer (20 mmol/L, pH 4.4) and identified on line by mass spectrometry.  相似文献   
102.
Drove roads are the traditional corridors used by pastoralists for seasonal movements of livestock (transhumance). They cover a considerable land area in Mediterranean countries and, although they are an obvious source of landscape diversity, their influence on the diversity and composition of animal assemblages has not been documented. Ant communities were studied on four active drove roads, two in forests (submediterranean and conifer) and two in open environments (croplands and rangelands). They were compared with the respective matrix communities and their contribution to local species richness was evaluated. The effects were heavily dependent on the open or closed nature of the matrix. In forest environments, drove roads increased ant species richness at the local scale, acting as clear keystone structures. Their species richness and functional diversity were highest on the fine scale, species composition was different, and a slight edge effect in the matrix was detected. In contrast, drove roads had little or even a negative effect in open environment locations. We conclude that drove roads have a high conservation value for ants in Mediterranean forest environments, in addition to their importance as reservoirs of plant biodiversity and generators of ecological goods and services.  相似文献   
103.
Abstract

Background: Supplementation of folic acid by pregnant mothers is thought to lower the risk of autism spectrum disorders (ASDs) in the offspring. Folic acid is taken up by cells via receptors with high affinity for folate and reduced folic acid derivatives. However, this is blocked by the presence of folate receptor autoantibodies (FRAA). Cerebral FRAA have been detected with high frequency in children with ASDs, suggesting the existence of a link between folic acid uptake and disease aetiology.

Methods: We investigated the frequency of FRAA in serum samples from 40 children with ASDs and 42 gender- and age-matched children with typical development (TD). Serum FRAA concentrations were measured by enzyme-linked immunosorbent assay.

Results: We found a significant difference in the frequency of serum FRAA in the two study cohorts. Serum FRAA were present in 77.5% (31/40) of children with ASDs compared with 54.8% (23/42) of TD children (p?=?0.03746, Fischer’s exact test). Thus, serum FRAA are more prevalent in children with ASDs than in TD children.

Conclusions: Our data suggest that children with ASDs may have defects in folic acid absorption that play a role in the onset of ASDs.  相似文献   
104.
This case study of the Estonian Genome Project (EGP) analyses the Estonian policy decision to construct a national human gene bank. Drawing upon qualitative data from newspaper articles and public policy documents, it focuses on how proponents use discourse to link the EGP to the broader political goal of securing Estonia's position within the Western/European scientific and cultural space. This dominant narrative is then situated within the analytical notion of the “brand state”, which raises potentially negative political consequences for this type of market‐driven genomic research. Considered against the increasing number of countries engaging in gene bank and/or gene database projects, this analysis of Estonia elucidates issues that cross national boundaries, while also illuminating factors specific to this small, post‐Soviet state as it enters the global biocybernetic economy.  相似文献   
105.
106.
The enteric nervous system is a vast network of neurons and glia running the length of the gastrointestinal tract that functionally controls gastrointestinal motility. A procedure for the isolation and culture of a mixed population of neurons and glia from the myenteric plexus is described. The primary cultures can be maintained for over 7 days, with connections developing among the neurons and glia. The longitudinal muscle strip with the attached myenteric plexus is stripped from the underlying circular muscle of the mouse ileum or colon and subjected to enzymatic digestion. In sterile conditions, the isolated neuronal and glia population are preserved within the pellet following centrifugation and plated on coverslips. Within 24-48 hr, neurite outgrowth occurs and neurons can be identified by pan-neuronal markers. After two days in culture, isolated neurons fire action potentials as observed by patch clamp studies. Furthermore, enteric glia can also be identified by GFAP staining. A network of neurons and glia in close apposition forms within 5 - 7 days. Enteric neurons can be individually and directly studied using methods such as immunohistochemistry, electrophysiology, calcium imaging, and single-cell PCR. Furthermore, this procedure can be performed in genetically modified animals. This methodology is simple to perform and inexpensive. Overall, this protocol exposes the components of the enteric nervous system in an easily manipulated manner so that we may better discover the functionality of the ENS in normal and disease states.  相似文献   
107.
《MABS-AUSTIN》2013,5(4):799-802
The commercial pipeline of monoclonal antibodies is highly dynamic, with a multitude of transitions occurring during the year as product candidates advance through the clinical phases and onto the market. The data presented here add to that provided in the extensive “Antibodies to watch in 2014” report published in the January/February 2014 issue of mAbs. Recent phase transition data suggest that 2014 may be a banner year for first approvals of antibody therapeutics. As of May 2014, three products, ramucirumab (Cyramza®), siltuximab (Sylvant®) and vedolizumab (EntyvioTM), had been granted first approvals in the United States, and four additional antibody therapeutics (secukinumab, dinutuximab, nivolumab, pembrolizumab) are undergoing regulatory review in either the US or the European Union. Other notable events include the start of first Phase 3 studies for seven antibody therapeutics (dupilumab, SA237, etrolizumab, MPDL3280A, bavituximab, clivatuzumab tetraxetan, blinatumomab). Relevant data for these product candidates are summarized, and metrics for antibody therapeutics development are discussed.  相似文献   
108.
张玲  陈静芳  陈磊  闫杰  王鹤  马庆良 《生物磁学》2013,(36):7176-7178
妊娠期高血压疾病是妊娠期特有的疾病,早期诊断对预后至关重要。妊娠期高血压疾病发病机制之一为血管内皮损伤,血浆中Hcy浓度升高会导致血管内皮损伤,血管内皮细胞功能失调常刺激超敏C反应蛋白(hs—cRP)的产生,而升高的hs—CRP可能导致血压上升。因此高血压和慢性炎症相互促进从而导致和加重了高血压。近年来血浆同型半胱氨酸(Hcy)、超敏C反应蛋白(hs—cRP)水平的升高与妊娠期高血压疾病的关系成为新的研究热点。本文将同型半胱氨酸、超敏C反应蛋白与妊娠期高血压疾病中的关系综述如下。  相似文献   
109.
目的:了解巴中地区上消化道出血反复发作的原因,为治疗提供临床循证医学证据。方法:通过对2011年4月~2012年11月巴中地区1134例上消化道出血中132例反复发作的患者进行调查统计,分析这上消化道出血反复发作的132例患者的年龄、生理特征、生活饮食习惯、精神状态、生活压力等多种相关因素。结果:发现饮食不当、精神紧张、腹腔感染、腹腔内压增高、输液输血过速、过量等是造成病情反复发作的主要诱因。结论:通过消除疾病的诱发因素,认真做好健康教育指导,积极治疗原发病是预防反复发作的有效措施。  相似文献   
110.
《Autophagy》2013,9(12):2099-2108
Excessive ethanol exposure is detrimental to the brain. The developing brain is particularly vulnerable to ethanol such that prenatal ethanol exposure causes fetal alcohol spectrum disorders (FASD). Neuronal loss in the brain is the most devastating consequence and is associated with mental retardation and other behavioral deficits observed in FASD. Since alcohol consumption during pregnancy has not declined, it is imperative to elucidate the underlying mechanisms and develop effective therapeutic strategies. One cellular mechanism that acts as a protective response for the central nervous system (CNS) is autophagy. Autophagy regulates lysosomal turnover of organelles and proteins within cells, and is involved in cell differentiation, survival, metabolism, and immunity. We have recently shown that ethanol activates autophagy in the developing brain. The autophagic preconditioning alleviates ethanol-induced neuron apoptosis, whereas inhibition of autophagy potentiates ethanol-stimulated reactive oxygen species (ROS) and exacerbates ethanol-induced neuroapoptosis. The expression of genes encoding proteins required for autophagy in the CNS is developmentally regulated; their levels are much lower during an ethanol-sensitive period than during an ethanol-resistant period. Ethanol may stimulate autophagy through multiple mechanisms; these include induction of oxidative stress and endoplasmic reticulum stress, modulation of MTOR and AMPK signaling, alterations in BCL2 family proteins, and disruption of intracellular calcium (Ca2+) homeostasis. This review discusses the most recent evidence regarding the involvement of autophagy in ethanol-mediated neurotoxicity as well as the potential therapeutic approach of targeting autophagic pathways.  相似文献   
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