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121.
Taher A Shammaa D Bazarbachi A Itani D Zaatari G Greige L Otrock ZK Mahfouz RA 《Molecular biology reports》2009,36(6):1555-1557
JAK2 is a cytoplasmic tyrosine kinase that has a vital role in signal transduction from several hemopoietic growth factor
receptors. The JAK2 V617F mutation has been implicated in a variety of diseases mainly related to myeloproliferative disorders including polycythemia
Vera, essential thrombocythemia, and idiopathic Myelofibrosis but has not been previously described in Thalassemia patients.
We studied 36 Lebanese patients diagnosed with thalassemia intermedia and assessed the presence or absence of the JAK2 V617F mutation using JAK2 activating mutation assay (In VivoScribe Technologies) and Polymerase Chain Reaction (PCR). None of the thalassemia intermedia patients were positive for this mutation.
To our knowledge, this study is the first to determine the status of JAK2 V617F mutation in thalassemia intermedia patients and expands the international published literature on JAK2. The latter’s V617F mutation does not seem to play a role in this hematologically important clinical entity. 相似文献
122.
123.
This study was conducted to investigate drone rearing activity and semen production of Apis mellifera ligustica and Apis mellifera syriaca . Tendency of worker bees of both subspecies towards egg laying under semiarid conditions were also monitored in the experiments. Differences were not observed in drone brood production between both honeybee subspecies throughout the investigation. Worker bees of both subspecies needed a significantly shorter time to start egg laying during February and March in comparison with the time those workers needed for laying eggs during the remaining months of the study. Syrian bee workers started egg laying earlier than Italian bee workers. Drones from laying workers were much smaller and produced less sperms with more abnormalities than normal drones. Drones produced from queens in May were heavier and produced more sperms with less abnormalities than those produced during the other months. The drone brood rearing of both subspecies tended to follow the same general cycle in 2005 and 2006. The study suggests that virgin queens have a better chance to receive adequate viable sperm amounts from drones in April and May in semiarid Mediterranean conditions. 相似文献
124.
S. Steiger-Barraissoul A. Rami 《Apoptosis : an international journal on programmed cell death》2009,14(11):1274-1288
Neuronal death induced by serum deprivation (SD) in HT22-cells was accompanied by a moderate activation of caspase-3, a prominent
upregulation of AIF and its translocation into the nucleus. In addition protein levels of autophagy markers such as LC3 and
beclin-1 were affected by SD. The ratio of LC3-II/LC3-I was significantly increased in serum deprived cultures. Furthermore,
the addition of the pan-caspase inhibitor z-VAD(OMe)-FMK (zVAD) does not protect HT22-cells from SD-induced neurodegeneration.
However, addition of the autophagy inhibitors such as 3-methyladenine (3-MA) or bafilomycin A1 (BafA1) provided a potentiation
of cell death induced by SD. z-VAD and 3-MA in combination were not only ineffective in rescuing cells from the damaging effects
of SD, but seem likely to act in synergy to potentiate slightly SD-induced cell death. The results of the current study suggest
that SD induced predominantly caspase-independent apoptosis in hippocampal HT22 cells and that inhibition of autophagy is
rather deleterious than protective. 相似文献
125.
A universal core genetic map for rice 总被引:1,自引:0,他引:1
Julie Orjuela Andrea Garavito Matthieu Bouniol Juan David Arbelaez Laura Moreno Jennifer Kimball Gregory Wilson Jean-François Rami Joe Tohme Susan R. McCouch Mathias Lorieux 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,120(3):563-572
To facilitate the creation of easily comparable, low-resolution genetic maps with evenly distributed markers in rice (Oryza sativa L.), we conceived of and developed a Universal Core Genetic Map (UCGM). With this aim, we derived a set of 165 anchors, representing clusters of three microsatellite or simple sequence repeat (SSR) markers arranged into non-recombining groups. Each anchor consists of at least three, closely linked SSRs, located within a distance below the genetic resolution provided by common, segregating populations (<500 individuals). We chose anchors that were evenly distributed across the rice chromosomes, with spacing between 2 and 3.5 Mbp (except in the telomeric regions, where spacing was 1.5 Mbp). Anchor selection was performed using in silico tools and data: the O. sativa cv. Nipponbare rice genome sequence, the CHARM tool, information from the Gramene database and the OrygenesDB database. Sixteen AA-genome accessions of the Oryza genus were used to evaluate polymorphisms for the selected markers, including accessions from O. sativa, O. glaberrima, O. barthii, O. rufipogon, O. glumaepatula and O. meridionalis. High levels of polymorphism were found for the tested O. sativa × O. glaberrima or O. sativa × wild rice combinations. We developed Paddy Map, a simple database that is helpful in selecting optimal sets of polymorphic SSRs for any cross that involves the previously mentioned species. Validation of the UCGM was done by using it to develop three interspecific genetic maps and by comparing genetic SSR locations with their physical positions on the rice pseudomolecules. In this study, we demonstrate that the UCGM is a useful tool for the rice genetics and breeding community, especially in strategies based on interspecific hybridisation. 相似文献
126.
Omi/HtrA2 is a pro-apoptotic mitochondrial serine protease involved in caspase-dependent as well as caspase-independent cell
death upon various brain injuries. However, the role of Omi/HtrA2 in neuronal death induced by status epilepticus (SE) in
the immature brain has not been reported. In this study, we analyzed the contribution of serine protease Omi/HtrA2, its substrate
X-linked inhibitor of apoptosis protein (XIAP) and the caspase-3 activation to damage of hippocamplal CA1 cells following
lithium-pilocarpine SE in P14 rat pups. Status epilepticus in the immature brain significantly induced translocation of Omi/HtrA2
from mitochondria into the cytosol, increased cytosolic accumulation of Omi/HtrA2, induced appearance of XIAP-breakdown products
and enhanced caspase-3 activity in the selectively vulnerable hippocampal CA1-subfield. Taken together, these results demonstrate
for the first time that SE in the immature brain results in Omi/HtrA2 accumulation in the cytosol, where it probably promotes
neuronal death by neutralizing and cleaving XIAP, one of the most potent endogenous inhibitors of apoptosis. 相似文献
127.
Kaufmann R Straussberg R Mandel H Fattal-Valevski A Ben-Zeev B Naamati A Shaag A Zenvirt S Konen O Mimouni-Bloch A Dobyns WB Edvardson S Pines O Elpeleg O 《American journal of human genetics》2010,87(5):667-670
Primary microcephaly of postnatal onset is a feature of many neurological disorders, mostly associated with mental retardation, seizures, and spasticity, and it typically carries a grave prognosis. Five infants from four unrelated families of Caucasus Jewish origin presented soon after birth with spasticity, epilepsy, and profound psychomotor retardation. Head circumference percentiles declined, and brain MRI disclosed marked cereberal and cerebellar atrophy with severe myelination defect. A search for a common homozygous region revealed a 2.28 Mb genomic segment on chromosome 11 that encompassed 16 protein-coding genes. A missense mutation in one of them, MED17, segregated with the disease state in the families and was carried by four of 79 anonymous Caucasus Jews. A corresponding mutation in the homologous S.cerevisiae gene SRB4 inactivated the protein, according to complementation assays. Screening of MED17 in additional patients with similar clinical and radiologic findings revealed four more patients, all homozygous for the p.L371P mutation and all originating from Caucasus Jewish families. We conclude that the p. L371P mutation in MED17 is a founder mutation in the Caucasus Jewish community and that homozygosity for this mutation is associated with infantile cerebral and cerebellar atrophy with poor myelination. 相似文献
128.
Rami Al Khudary Ramprasath Venkatachalam Moritz Katzer Skander Elleuche Garabed Antranikian 《Extremophiles : life under extreme conditions》2010,14(3):273-285
A gene encoding an esterase (estO) was identified and sequenced from a gene library screen of the psychrotolerant bacterium Pseudoalteromonas arctica. Analysis of the 1,203 bp coding region revealed that the deduced peptide sequence is composed of 400 amino acids with a
predicted molecular mass of 44.1 kDa. EstO contains a N-terminal esterase domain and an additional OsmC domain at the C-terminus
(osmotically induced family of proteins). The highly conserved five-residue motif typical for all α/β hydrolases (G × S × G)
was detected from position 104 to 108 together with a putative catalytic triad consisting of Ser106, Asp196, and His225. Sequence comparison showed that EstO exhibits 90% amino acid identity with hypothetical proteins containing similar esterase
and OsmC domains but only around 10% identity to the amino acid sequences of known esterases. EstO variants with and without
the OsmC domain were produced and purified as His-tag fusion proteins in E. coli. EstO displayed an optimum pH of 7.5 and optimum temperature of 25°C with more than 50% retained activity at the freezing
point of water. The thermostability of EstO (50% activity after 5 h at 40°C) dramatically increased in the truncated variant
(50% activity after 2.5 h at 90°C). Furthermore, the esterase displays broad substrate specificity for esters of short-chain
fatty acids (C2–C8). 相似文献
129.
Background
Short interstitial telomere motifs (telo boxes) are short sequences identical to plant telomere repeat units. They are observed within the 5' region of several genes over-expressed in cycling cells. In synergy with various cis-acting elements, these motifs participate in the activation of expression. Here, we have analysed the distribution of telo boxes within Arabidopsis thaliana and Oryza sativa genomes and their association with genes involved in the biogenesis of the translational apparatus. 相似文献130.
Eric Bourhis Christine Tam Yvonne Franke J. Fernando Bazan James Ernst Jiyoung Hwang Mike Costa Andrea G. Cochran Rami N. Hannoush 《The Journal of biological chemistry》2010,285(12):9172-9179
Wnt/β-catenin signaling is initiated at the cell surface by association of secreted Wnt with its receptors Frizzled (Fz) and low density lipoprotein receptor-related protein 5/6 (LRP5/6). The study of these molecular interactions has been a significant technical challenge because the proteins have been inaccessible in sufficient purity and quantity. In this report we describe insect cell expression and purification of soluble mouse Fz8 cysteine-rich domain and human LRP6 extracellular domain and show that they inhibit Wnt/β-catenin signaling in cellular assays. We determine the binding affinities of Wnts and Dickkopf 1 (Dkk1) to the relevant co-receptors and reconstitute in vitro the Fz8 CRD·Wnt3a·LRP6 signaling complex. Using purified fragments of LRP6, we further show that Wnt3a binds to a region including only the third and fourth β-propeller domains of LRP6 (E3E4). Surprisingly, we find that Wnt9b binds to a different part of the LRP6 extracellular domain, E1E2, and we demonstrate that Wnt3a and Wnt9b can bind to LRP6 simultaneously. Dkk1 binds to both E1E2 and E3E4 fragments and competes with both Wnt3a and Wnt9b for binding to LRP6. The existence of multiple, independent Wnt binding sites on the LRP6 co-receptor suggests new possibilities for the architecture of Wnt signaling complexes and a model for broad-spectrum inhibition of Wnt/β-catenin signaling by Dkk1. 相似文献