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441.
Molecular Biology Reports - Multiple sclerosis (MS) is an autoimmune-type inflammatory disorder in human central nervous system. Recombinant interferon beta (IFN-β) decreases the number of...  相似文献   
442.
Fibroblast growth factor 23 (FGF23) is a hormone required for normal renal phosphate reabsorption. FGF23 gain-of-function mutations result in autosomal dominant hypophosphatemic rickets (ADHR), and FGF23 loss-of-function mutations cause familial hyperphosphatemic tumoral calcinosis (TC). In this study, we identified a novel recessive FGF23 TC mutation, a lysine (K) substitution for glutamine (Q) (160 C>A) at residue 54 (Q54K). To understand the molecular consequences of all known FGF23-TC mutants (H41Q, S71G, M96T, S129F, and Q54K), these proteins were stably expressed in vitro. Western analyses revealed minimal amounts of secreted intact protein for all mutants, and ELISA analyses demonstrated high levels of secreted COOH-terminal FGF23 fragments but low amounts of intact protein, consistent with TC patients' FGF23 serum profiles. Mutant protein function was tested and showed residual, yet decreased, bioactivity compared with wild-type protein. In examining the role of the FGF23 COOH-terminal tail (residues 180-251) in protein processing and activity, truncated mutants revealed that the majority of the residues downstream from the known FGF23 SPC protease site ((176)RXXR(179)/S(180)) were not required for protein secretion. However, residues adjacent to the RXXR site (between residues 188 and 202) were required for full bioactivity. In summary, we report a novel TC mutation and demonstrate a common defect of reduced FGF23 stability for all known FGF23-TC mutants. Finally, the majority of the COOH-terminal tail of FGF23 is not required for protein secretion but is required for full bioactivity.  相似文献   
443.
Thymus daenensis is an aromatic medicinal plant endemic to Iran. We used inter simple sequence repeat (ISSR) markers to detect genetic polymorphism in this herb using 17 T. daenensis accessions collected from different geographic regions in Iran. The 15 primers chosen for analysis revealed 256 bands, of which 228 (88.9%) were polymorphic. Jaccard’s similarity indices based on ISSR profiles were subjected to UPGMA cluster analysis. The generated dendrogram revealed two major groups. The Tc group included the accessions collected from the center of the Zagros Mountains, and the Te group was collected from the extremes of the Zagros range. A principal coordinate analysis confirmed the results of clustering. The results showed that the divergence of accessions based on the Zagros Mountains is more logical in comparison with classification on the basis of provincial borders. Gene diversity and expected heterozygosity were greater in the Tc group than in the Te group, suggesting that the germplasm collected from the center of the Zagros Mountains is more variable.  相似文献   
444.
Complications of chemotherapy, such as appearance of multidrug resistance, have persuaded researchers to consider phage therapy as a new method to combat bacterial infections. In vitro experiments were performed to assess the therapeutic value of genetically modified phages for controlling gastrointestinal Escherichia coli O157:H7 cells in Luria–Bertani (LB) media and contaminated cow milk. We constructed a modified nonreplicating M13-derived phage expressing a lethal catabolite gene activator protein (CAP) that is a Glu181Gln mutant of CAP. The modified phagemid was propagated in the lethal CAP-resistant strain XA3DII. Time–kill assay experiments showed a considerable reduction in the number of surviving bacteria in both LB media and contaminated cow milk. Our further study using other test strains demonstrated that the host range of lethal phage is limited to E. coli strains that produce pili. This study provides a possible strategy for the exploitation of genetically engineered nonlytic phages as bactericidal agents by minimizing the risk of release of progeny phages and endotoxins into the environment. The phage was engineered to remain lethal to its bacterial target, but incapable of replicating therein. Furthermore, the addition of an inducer to express the lethal protein is not required.  相似文献   
445.
Iranian Tissue Bank prepares a wide range of human tissue homografts such as; heart valve, bone, skin, amniotic membrane and other tissues for different clinical applications. The purpose of this study was to determine the seroprevalence of HTLV in tissue donors. About 1,548 tissue donors were studied during a 5-years period by ELISA assays. HTLV1,2—antibodies were tested for all of donors with other tests upon American Association of Tissue Banks (AATB) standards. About 25 (1.61%) out of 1,548 tissue donors were HTLV positive that 17 donors were male and 8 were female (female/male ratio was approximately 47%). Regarding to the prevalence of HTLV among tissue donors and importance of cell and tissue safety and quality assurance, we recommend that all blood, cell and tissue banks should be involved both routine serological methods and other complementary tests such as polymerase chain reaction (PCR) for diagnosis of HTLV.  相似文献   
446.
Background:Retinoic acid (RA) plays a key role in naïve T cell differentiation into FOXP3+ Treg cell in the respiratory airways. The present study aims to investigate RA and Treg-related cytokine serum levels, salivary IgA levels, FOXP3 and IL-4 gene expression, and the relationships between RA serum levels and Treg-related cytokines in allergic rhinitis (AR) patients and healthy controls.Methods:Salivary IgA and serum IgE, RA, IL-10, and TGF-β concentrations were measured by ELISA in 37 AR patients and 30 age- and sex-matched healthy controls.Results:IL-10 and TGF-β concentrations were significantly less in AR patients than in healthy controls (p< 0.01 and P< 0.0001, respectively). Salivary IgA was significantly greater in patients than in controls (p< 0.05). RA was not significantly different between patients and controls (p> 0.05); however, a significant positive correlation was found between serum RA and both IL-10 and TGF-β in AR patients.Conclusion:Our data suggest that RA may influence AR risk via affecting the TGF-β and IL-10 production.Key Words: Allergic Rhinitis, Interleukin-10, Obesity, Retinoic Acid, Transforming Growth Factor-β  相似文献   
447.
Cyclooxygenase-2 (COX-2) inhibitors including celecoxib inhibit cell growth and induce apoptosis in cancer cells. In this study, the relation of Bax (an apoptosis promoter) to Bcl-2 (an apoptosis inhibitor) ratio with the apoptosis co-ordination enzyme, caspase-3 was investigated in correlation with the treatment of 4,5-bisaryl imidazolyl imidazoles as novel selective COX-2 inhibitors in Caco-2 colorectal cancer cells. Recently, the organic reactions under microwave irradiation attracted attention of scientists due to their high reaction rate, mild reaction conditions and the formation of clean products. Therefore, a microwave-assisted method was used to synthesize our compounds. The effects of these COX-2 inhibitors on the proliferation of Caco-2 cells were evaluated by MTT assay. cDNA microarray and clustering analysis were used to evaluate effects of our synthetic compounds on gene expression pattern of 112 genes involved in apoptosis pathways. Bax, Bcl-2 and caspase-3 mRNA expression and their relationship were analyzed by quantitative real-time PCR. Results indicated that proliferation of Caco-2 cells after treatment with 4,5-bisaryl imidazolyl imidazoles on Caco-2 cells were time and dose dependent. We conclude that increase in Bax/Bcl-2 ratio leads to an up-regulation in caspase-3 mRNA expression.  相似文献   
448.

Traumatic brain injury (TBI) is known as an acute degenerative pathology of the central nervous system, and has been shown to increase brain aquaporin 4 (AQP4) expression. Various molecular mechanisms affect AQP4 expression, including neuronal high mobility group box 1, forkhead box O3a, vascular endothelial growth factor, hypoxia-inducible factor-1 α (HIF-1 α) sirtuin 2, NF-κB, Malat1, nerve growth factor and Angiotensin II receptor type 1. In addition, inhibition of AQP4 with FK-506, MK-801 (indirectly by targeting N-methyl-d-aspartate receptor), inactivation of adenosine A2A receptor, levetiracetam, adjudin, progesterone, estrogen, V1aR inhibitor, hypertonic saline, erythropoietin, poloxamer 188, brilliant blue G, HIF-1alpha inhibitor, normobaric oxygen therapy, astaxanthin, epigallocatechin-3-gallate, sesamin, thaliporphine, magnesium, prebiotic fiber, resveratrol and omega-3, as well as AQP4 gene silencing lead to reduced edema upon TBI. This review summarizes current knowledge and evidence on the relationship between AQP4 and TBI, and the potential mechanisms involved.

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449.

Background  

There are many methods for analyzing microarray data that group together genes having similar patterns of expression over all conditions tested. However, in many instances the biologically important goal is to identify relatively small sets of genes that share coherent expression across only some conditions, rather than all or most conditions as required in traditional clustering; e.g. genes that are highly up-regulated and/or down-regulated similarly across only a subset of conditions. Equally important is the need to learn which conditions are the decisive ones in forming such gene sets of interest, and how they relate to diverse conditional covariates, such as disease diagnosis or prognosis.  相似文献   
450.
The misfolding of specific proteins is often associated with their assembly into fibrillar aggregates, commonly termed amyloid fibrils. Despite the many efforts expended to characterize amyloid formation in vitro, there is no deep knowledge about the environment (in which aggregation occurs) as well as mechanism of this type of protein aggregation. Alpha-chymotrypsin was recently driven toward amyloid aggregation by the addition of intermediate concentrations of trifluoroethanol. In the present study, approaches such as turbidimetric, thermodynamic, intrinsic fluorescence and quenching studies as well as chemical modification have been successfully used to elucidate the underlying role of hydrophobic interactions (involved in early stages of amyloid formation) in α-chymotrypsin-based experimental system.  相似文献   
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