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International Journal of Peptide Research and Therapeutics - Fibroblast growth factor 21 (FGF21) is a metabolic regulator with a wide range of biological functions. Although previous studies have...  相似文献   
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A suitable bioreactor system for large scale embryo-to-plantlets conversion of Kalopanax septemlobus was established. In temporary immersion with net (TIN) bioreactor, 85% of embryos successfully produced plantlets whereas in continuous immersion with net (CIN) bioreactor, only conversion rate of 29.3% was obtained. Embryos cultured in TIN bioreactor produced more vigorous plantlets in terms of fresh weight, height, root length, roots and leaves quantity. In CIN bioreactor, Kalopanax plantlets showed high malondialdehyde (MDA) content and increased activities of reactive oxygen species (ROS)-processing enzymes, such as ascorbate peroxidase (APX) and glutathione reductase (GR) indicating the occurrence of oxidative stress. However, superoxide dismutase (SOD) and catalase (CAT) showed similar activities in plantlets grown in different bioreactors. Kalopanax plantlets grown in both TIN and CIN bioreactors were harvested and transferred to greenhouse for their acclimatization. Plantlets grown in CIN bioreactor exhibited low survival rate (75.8%) compared to those grown in TIN bioreactor (100%). MDA content decreased with progression of acclimatization indicating a decrease in oxidative stress. However, MDA level in CIN derived plantlets was higher than TIN derived plantlets. In TIN derived plantlets, an increase in SOD and GR activities were observed after 1 week and thereafter decreased. CAT activity decreased while APX activity started to increase after 1 week of acclimatization. The results indicated that Kalopanax plantlets were able to overcome oxidative stress mainly through SOD activity. However, levels of antioxidant enzyme activities were higher in CIN derived plantlets than TIN derived plantlets. Kalopanax plantlets obtained from TIN bioreactor performed better during the acclimatization phase and showed higher survival rate than material obtained on CIN bioreactor or conventional culture systems.  相似文献   
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International Journal of Peptide Research and Therapeutics - Acinetobacter baumannii is an important pathogen responsible for nosocomial infections worldwide. Trimeric autotransporters, the...  相似文献   
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Human influenza A viruses (IAVs) cause global pandemics and epidemics, which remains a nonignorable serious concern for public health worldwide. To combat the surge of viral outbreaks, new treatments are urgently needed. Here, we design a new vaccine based on virus-like particles (VLPs) and show how intranasal administration of this vaccine triggers protective immunity, which can be exploited for the development of new therapies. H1N1 VLPs were produced in baculovirus vectors and were injected into BALB/c mice by the intramuscular (IM) or intranasal (IN) route. We found that there were significantly higher inflammatory cell and lymphocyte concentrations in bronchoalveolar lavage samples and the lungs of IN immunized mice; however, the IM group had little signs of inflammatory responses. On the basis of our results, immunization with H1N1 influenza VLP elicited a strong T cell immunity in BALB/c mice. Despite T cell immunity amplification after both IN and IM vaccination methods in mice, IN-induced T cell responses were significantly more intense than IM-induced responses, and this was likely related to an increased number of both CD11bhigh and CD103+ dendritic cells in mice lungs after IN administration of VLP. Furthermore, evaluation of interleukin-4 and interferon gamma cytokines along with several chemokine receptors showed that VLP vaccination via IN and IM routes leads to a greater CD4+ Th1 and Th2 response, respectively. Our findings indicated that VLPs represent a potential strategy for the development of an effective influenza vaccine; however, employing relevant routes for vaccination can be another important part of the universal influenza vaccine puzzle.  相似文献   
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Breast cancer (BC) is the most frequently occurring malignancy in women worldwide. Despite the substantial advancement in understanding the molecular mechanisms and management of BC, it remains the leading cause of cancer death in women. One of the main reasons for this obstacle is that we have not been able to find the Achilles heel for the BC as a highly heterogeneous disease. Accumulating evidence has revealed that noncoding RNAs (ncRNAs), play key roles in the development of BC; however, the involving of complex regulatory interactions between the different varieties of ncRNAs in the development of this cancer has been poorly understood. In the recent years, the newly discovered mechanism in the RNA world is “competing endogenous RNA (ceRNA)” which proposes regulatory dialogues between different RNAs, including long ncRNAs (lncRNAs), microRNAs (miRNAs), transcribed pseudogenes, and circular RNAs (circRNAs). In the latest BC research, various studies have revealed that dysregulation of several ceRNA networks (ceRNETs) between these ncRNAs has fundamental roles in establishing the hallmarks of BC development. And it is thought that such a discovery could open a new window for a better understanding of the hidden aspects of breast tumors. Besides, it probably can provide new biomarkers and potential efficient therapeutic targets for BC. This review will discuss the existing body of knowledge regarding the key functions of ceRNETs and then highlights the emerging roles of some recently discovered ceRNETs in several hallmarks of BC. Moreover, we propose for the first time the “ceRnome” as a new term in the present article for RNA research.  相似文献   
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Obesity as a multifactorial disorder has been shown a dramatically growing trend recently. Besides genetic and environmental factors, dysregulation of the endocannabinoid system tone is involved in the pathogenesis of obesity. This study reviewed the potential efficacy of Oleoylethanolamide (OEA) as an endocannabinoid-like compound in the energy homeostasis and appetite control in people with obesity. OEA as a lipid mediator and bioactive endogenous ethanolamide fatty acid is structurally similar to the endocannabinoid system compounds; nevertheless, it is unable to induce to the cannabinoid receptors. Unlike endocannabinoids, OEA negatively acts on the food intake and suppress appetite via various mechanisms. Indeed, OEA as a ligand of PPAR-α, GPR-119, and TRPV1 receptors participates in the regulation of energy intake and energy expenditure, feeding behavior, and weight gain control. OEA delays meal initiation, reduces meal size, and increases intervals between meals. Considering side effects of some approaches used for the management of obesity such as antiobesity drugs and surgery as well as based on sufficient evidence about the protective effects of OEA in the improvement of common abnormalities in people with obese, its supplementation as a novel efficient and FDA approved pharmaceutical agent can be recommended.  相似文献   
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Trypanosomatid parasites are responsible for various human diseases, such as sleeping sickness, animal trypanosomiasis, or cutaneous and visceral leishmaniases. The few available drugs to fight related parasitic infections are often toxic and present poor efficiency and specificity, and thus, finding new molecular targets is imperative. Aminoacyl-tRNA synthetases (aaRSs) are essential components of the translational machinery as they catalyze the specific attachment of an amino acid onto cognate tRNA(s). In trypanosomatids, one gene encodes both cytosolic- and mitochondrial-targeted aaRSs, with only three exceptions. We identify here a unique specific feature of aaRSs from trypanosomatids, which is that most of them harbor distinct insertion and/or extension sequences. Among the 26 identified aaRSs in the trypanosome Leishmania tarentolae, 14 contain an additional domain or a terminal extension, confirmed in mature mRNAs by direct cDNA nanopore sequencing. Moreover, these RNA-Seq data led us to address the question of aaRS dual localization and to determine splice-site locations and the 5′-UTR lengths for each mature aaRS-encoding mRNA. Altogether, our results provided evidence for at least one specific mechanism responsible for mitochondrial addressing of some L. tarentolae aaRSs. We propose that these newly identified features of trypanosomatid aaRSs could be developed as relevant drug targets to combat the diseases caused by these parasites.  相似文献   
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The association between adipose tissue and immunity has been established and fat-associated lymphoid clusters (FALCs) are considered as a source of immune cells. We discovered lymphoid clusters (LCs) in mouse mediastinal fat tissues (MFTs). In Th1-biased C57BL/6N (B6), Th2-biased DBA/2Cr (DBA) and autoimmune-prone MRL/MpJ (MRL) mice strains, LCs without a fibrous capsule and germinal center were observed in white-colored MFTs extending from the diaphragm to the heart. The number and size of the LCs were larger in 12-month-old mice than in 3-month-old mice in all of the examined strains. Moreover, B6 had an especially large number of LCs compared with DBA and MRL. The immune cells in the LCs consisted of mainly T-cells and some B-cells. The majority of T-cells were CD4+ helper T (Th) cells, rather than CD8+ cytotoxic T-cells and no obvious immune cell population difference was present among the strains. Furthermore, high endothelial venules and lymphatic vessels in the LCs were better developed in B6 mice than in the other strains. Interestingly, some CD133+ hematopoietic progenitor cells and some c-Kit+/CD127+ natural helper cells were detected in the LCs. BrdU+ proliferating cells were more abundant in the LCs of B6 mice than in the LCs of the other strains and the number of BrdU+ cells increased with age. This is the first report of LCs in mouse MFTs. We suggest that the mouse genetic background affects LC size and number. We term the LCs “mediastinal fat-associated lymphoid clusters”. These clusters can be considered as niches for Th cell production.  相似文献   
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Calprotectin (CP) is widely considered to have diverse roles including growth inhibitory and apoptosis induction in a number of tumor cell lines and antimicrobial activities. As CP has been proposed to bind metal ions with high affinity, we have studied its functional and primarily its structural behavior upon Zn2+ and Mn2+ chelation solely and along with Ca2+. We employed fluorescence spectroscopy and circular dichroism to determine the resulting modifications. Based upon our findings it is clear that treating CP with ions effectively weakened its natural growth inhibitory activity. Moreover, structural analysis of Zn2+ and Mn2+-treated CPs indicated remarkable alterations in the regular secondary structures in favor of irregular structures while Zn2+ and Mn2+ treatment of CP after incubation with Ca2+ displayed no remarkable shifts. Tertiary structure investigation using fluorescence spectroscopy showed that CP undergoes conformational changes upon Zn2+ and Mn2+ treatment whereby Trp residues of protein is slightly exposed to the hydrophilic environment, compactness of CP is compromised, whereas in Ca2+-treated CP, the tertiary structure integrity is intact upon Zn2+ and Mn2+ chelation. Interestingly, CP structural modifications upon Zn2+ and Mn2+ treatment was significantly comparable, probably due to similar radii and charges of ions. Taken all together, we have concluded that CP maintains its normal nature in Ca2+-loaded state when treated with Zn2+ and Mn2+ ions. It can be suggested that Ca2+ not only stabilize CP structure but also helps CP to keep its structure upon metal ions chelation which is involved in host organism defense system.  相似文献   
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