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31.
Health risk for well drinking water is a worldwide problem. Our recent studies showed increased toxicity by exposure to barium alone (≤700 µg/L) and coexposure to barium (137 µg/L) and arsenic (225 µg/L). The present edition of WHO health-based guidelines for drinking water revised in 2011 has maintained the values of arsenic (10 µg/L) and barium (700 µg/L), but not elements such as manganese, iron and zinc. Nevertheless, there have been very few studies on barium in drinking water and human samples. This study showed significant correlations between levels of arsenic and barium, but not its homologous elements (magnesium, calcium and strontium), in urine, toenail and hair samples obtained from residents of Jessore, Bangladesh. Significant correlation between levels of arsenic and barium in well drinking water and levels in human urine, toenail and hair samples were also observed. Based on these results, a high-performance and low-cost adsorbent composed of a hydrotalcite-like compound for barium and arsenic was developed. The adsorbent reduced levels of barium and arsenic from well water in Bangladesh and Vietnam to <7 µg/L within 1 min. Thus, we have showed levels of arsenic and barium in humans and propose a novel remediation system.  相似文献   
32.

Background

Autism spectrum disorders (ASDs) are caused by both genetic and environmental factors. Mitochondria act to connect genes and environment by regulating gene-encoded metabolic networks according to changes in the chemistry of the cell and its environment. Mitochondrial ATP and other metabolites are mitokines—signaling molecules made in mitochondria—that undergo regulated release from cells to communicate cellular health and danger to neighboring cells via purinergic signaling. The role of purinergic signaling has not yet been explored in autism spectrum disorders.

Objectives and Methods

We used the maternal immune activation (MIA) mouse model of gestational poly(IC) exposure and treatment with the non-selective purinergic antagonist suramin to test the role of purinergic signaling in C57BL/6J mice.

Results

We found that antipurinergic therapy (APT) corrected 16 multisystem abnormalities that defined the ASD-like phenotype in this model. These included correction of the core social deficits and sensorimotor coordination abnormalities, prevention of cerebellar Purkinje cell loss, correction of the ultrastructural synaptic dysmorphology, and correction of the hypothermia, metabolic, mitochondrial, P2Y2 and P2X7 purinergic receptor expression, and ERK1/2 and CAMKII signal transduction abnormalities.

Conclusions

Hyperpurinergia is a fundamental and treatable feature of the multisystem abnormalities in the poly(IC) mouse model of autism spectrum disorders. Antipurinergic therapy provides a new tool for refining current concepts of pathogenesis in autism and related spectrum disorders, and represents a fresh path forward for new drug development.  相似文献   
33.
A panel of geochemical techniques is used here to investigate the taphonomy of fossil feathers preserved in association with the skeleton of the Jurassic theropod Anchiornis huxleyi. Extant feathers were analysed in parallel to test whether the soft tissues morphologically preserved in the fossil also exhibit a high degree of chemical preservation. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) indicate that clays and iron oxide pseudomorphs occur in the surrounding sediment and also reveal the preservation of melanosome-like microbodies in the fossil. Carbon gradient along a depth profile and co-occurrence of carbon and sulphur are shown in the fossil by elastic backscattering (EBS) and particle-induced x-ray emission (PIXE), which are promising techniques for the elemental analysis of fossil soft tissues. The molecular composition of modern and fossil soft tissues was assessed from micro-attenuated total reflectance fourier transform infrared spectroscopy (micro-ATR FTIR), solid-state 13C nuclear magnetic resonance (CP-MAS 13C NMR) and pyrolysis gas chromatography mass spectrometry in the presence of TMAH (TMAH-Py-GC-MS). Results indicate that the proteinaceous material that comprises the modern feathers is not present in the fossil feathers. The fossil feathers and the embedding sediment exhibit a highly aliphatic character. However, substantial differences exist between these samples, revealing that the organic matter of the fossil feathers is, at least partially, derived from original constituents of the feathers. Our results suggest that, despite the morphological preservation of Anchiornis feathers, original proteins, that is keratin, were probably not preserved in the 160-myr-old feathers.  相似文献   
34.
Although the function and regulation of SnRK1 have been studied in various plants, its molecular mechanisms in response to abiotic stresses are still elusive. In this work, we identified an AP2/ERF domain-containing protein (designated GsERF7) interacting with GsSnRK1 from a wild soybean cDNA library. GsERF7 gene expressed dominantly in wild soybean roots and was responsive to ethylene, salt, and alkaline. GsERF7 bound GCC cis-acting element and could be phosphorylated on S36 by GsSnRK1. GsERF7 phosphorylation facilitated its translocation from cytoplasm to nucleus and enhanced its transactivation activity. When coexpressed in the hairy roots of soybean seedlings, GsSnRK1(wt) and GsERF7(wt) promoted plants to generate higher tolerance to salt and alkaline stresses than their mutated species, suggesting that GsSnRK1 may function as a biochemical and genetic upstream kinase of GsERF7 to regulate plant adaptation to environmental stresses. Furthermore, the altered expression patterns of representative abiotic stress-responsive and hormone-synthetic genes were determined in transgenic soybean hairy roots after stress treatments. These results will aid our understanding of molecular mechanism of how SnRK1 kinase plays a cardinal role in regulating plant stress resistances through activating the biological functions of downstream factors.  相似文献   
35.

Recent studies continue to find evidence linking Type 2 diabetes (T2D) with Alzheimer's disease (AD), the most common cause of dementia, a general term for memory loss and other cognitive abilities serious enough to interfere with daily life. Insulin resistance or dysfunction of insulin signaling is a universal feature of T2D, the main culprit for altered glucose metabolism and its interdependence on cell death pathways, forming the basis of linking T2D with AD as it may exacerbate Aβ accumulation, tau hyperphosphorylation and devastates glucose transportation, energy metabolism, hippocampal framework and promulgate inflammatory pathways. The current work demonstrates the basic mechanisms of the insulin resistance mediates dysregulation of bioenergetics and progress to AD as a mechanistic link between diabetes mellitus and AD. This work also aimed to provide a potential and feasible zone to succeed in the development of therapies in AD by enhanced hypometabolism and altered insulin signaling.

  相似文献   
36.
The objective of our study was to examine the effect of local environmental conditions, especially air temperature and rainfall, in two agro-ecological regions in Vietnam on the population dynamics of Meloidogyne incognita on black pepper plants and on percentage root galling. The two study sites were situated in Cam Lo, Quang Tri province (North Central Coast) and Buon Ma Thuot, Dac Lac province (Central Highlands). At the study sites, 13 plant-parasitic nematode taxa belonging to 12 genera were identified. Ten of these taxa were present in both study sites. Helicotylenchus certus, Hemicriconemoides cocophilus and Pratylenchus coffeae were only found in Buon Ma Thuot. Based on nematode population densities, M. incognita was the most abundant taxon present. Rainfall and air temperature differed significantly between the two study sites. The most important climatic difference was rainfall: in Buon Ma Thuot, the rainy season lasted 2 months longer and the monthly rainfall during the rainy season was much higher compared to Cam Lo. Although this difference resulted in some differences in the population dynamics of M. incognita in the soil and roots of the black pepper variety Vinh Linh, the highest root population densities were observed in both study sites during the first half of the dry season. In Cam Lo, the highest percentage root galling was observed during the first half of the dry season. In Buon Ma Thuot, the highest percentage root galling was observed towards the end of the rainy season. Estimating the population densities if M. incognita to decide on the application of a management strategy should be done during the first half of the dry season.  相似文献   
37.
The sequence of the chloroplast genome, which is inherited maternally, contains useful information for many scientific fields such as plant systematics, biogeography and biotechnology because its characteristics are highly conserved among species. There is an increase in chloroplast genomes of angiosperms that have been sequenced in recent years. In this study, the nucleotide sequence of the chloroplast genome (cpDNA) of Veratrum patulum Loes. (Melanthiaceae, Liliales) was analyzed completely. The circular double-stranded DNA of 153,699 bp consists of two inverted repeat (IR) regions of 26,360 bp each, a large single copy of 83,372 bp, and a small single copy of 17,607 bp. This plastome contains 81 protein-coding genes, 30 distinct tRNA and four genes of rRNA. In addition, there are six hypothetical coding regions (ycf1, ycf2, ycf3, ycf4, ycf15 and ycf68) and two open reading frames (ORF42 and ORF56), which are also found in the chloroplast genomes of the other species. The gene orders and gene contents of the V. patulum plastid genome are similar to that of Smilax china, Lilium longiflorum and Alstroemeria aurea, members of the Smilacaceae, Liliaceae and Alstroemeriaceae (Liliales), respectively. However, the loss rps16 exon 2 in V. patulum results in the difference in the large single copy regions in comparison with other species. The base substitution rate is quite similar among genes of these species. Additionally, the base substitution rate of inverted repeat region was smaller than that of single copy regions in all observed species of Liliales. The IR regions were expanded to trnH_GUG in V. patulum, a part of rps19 in L. longiflorum and A. aurea, and whole sequence of rps19 in S. china. Furthermore, the IGS lengths of rbcL-accD-psaI region were variable among Liliales species, suggesting that this region might be a hotspot of indel events and the informative site for phylogenetic studies in Liliales. In general, the whole chloroplast genome of V. patulum, a potential medicinal plant, will contribute to research on the genetic applications of this genus.  相似文献   
38.
Glioblastoma multiforme (GBM) cells invade along the existing normal capillaries in brain. Normal capillary endothelial cells function as the blood–brain barrier (BBB) that limits permeability of chemicals into the brain. To investigate whether GBM cells modulate the BBB function of normal endothelial cells, we developed a new in vitro BBB model with primary cultures of rat brain endothelial cells (RBECs), pericytes, and astrocytes. Cells were plated on a membrane with 8 μm pores, either as a monolayer or as a BBB model with triple layer culture. The BBB model consisted of RBEC on the luminal side as a bottom, and pericytes and astrocytes on the abluminal side as a top of the chamber. Human GBM cell line, LN-18 cells, or lung cancer cell line, NCI-H1299 cells, placed on either the RBEC monolayer or the BBB model increased the transendothelial electrical resistance (TEER) values against the model, which peaked within 72 h after the tumor cell application. The TEER value gradually returned to baseline with LN-18 cells, whereas the value quickly dropped to the baseline in 24 h with NCI-H1299 cells. NCI-H1299 cells invaded into the RBEC layer through the membrane, but LN-18 cells did not. Fibroblast growth factor 2 (FGF-2) strengthens the endothelial cell BBB function by increased occludin and ZO-1 expression. In our model, LN-18 and NCI-H1299 cells secreted FGF-2, and a neutralization antibody to FGF-2 inhibited LN-18 cells enhanced BBB function. These results suggest that FGF-2 would be a novel therapeutic target for GBM in the perivascular invasive front.  相似文献   
39.
Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most economically important swine pathogens because it is highly infectious and causes economic losses due to decreased pig productivity. In this study, the 603 bp complete major envelope protein encoding gene (ORF5) of 32 field PRRSV isolates from Vietnam collected during 2008–2012 were sequenced and analyzed. Multiple nucleotide (nt) and deduced amino acid (aa) alignments of ORF5 were performed on the 32 isolates: the representative strains (European and North American genotypes), Chinese strains available in GenBank and vaccine strains licensed for use in Vietnam. The results showed 94.8–100.0% nt identity and 94.0–100% aa similarity among the 32 isolates. These isolates shared similarities with the prototype of the North American PRRSV strain (VR‐2332; nt 87.8–89.3%, aa 87.5–90.0%), and Lelystat virus, the prototype of the European PRRSV strain (LV; nt 61.1–61.9%, aa 55.1‐57.0%). There was greater similarity with QN07 (nt 96.5‐98.5%, aa 96.0‐99.0%) from the 2007 PRRS outbreak in QuangNam Province, CH‐1a (nt 93.2–95.1%, 91.5–93.5%) isolated in China in 1995 and JXA1 (nt 96.5–98.6%, aa 95.0–98.0%), the highly pathogenic strain from China isolated in 2006. The Vietnamese isolates were more similar to JXA1‐R (nt 96.5–98.6%, aa 95.0–98.0%), the strain used in Chinese vaccines, than to Ingelvac MLV/BSL‐PS (nt 87.2–89.0%, aa 86.0–89.0%). Phylogenetic analysis showed that the 32 isolates were of the North American genotype and classified into sub‐lineage 8.7. This sub‐lineage contains highly pathogenic Chinese PRRSV strains. This study documents genetic variation in circulating PRRSV strains and could assist more effective use of PRRS vaccines in Vietnam.  相似文献   
40.
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