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Spermatogonial stem cells are unique cells of testes that can restore fertility upon transplantation into recipient testes. However, use of suitable markers for enrichment of these cells have important potential application. THY1, is an established conserved marker of spermatogonial stem cells in bovine, rodents, and primates, but there is no information available in goats. After three rounds of enzymatic digestion of prepubertal goat testicular tissues, undifferentiated spermatogonia positive for THY1 were isolated by magnetic-activated cell sorting and were used for immunocytochemistry, real-time polymerase chain reaction analysis for gene expression, protein expression, and transplantation into recipient mice. Immunocytochemical analyses showed that significantly higher percentage of THY1+ cells were positive for PLZF and VASA when compared with unselected population. This result for PLZF was further confirmed at the protein level. Real-time polymerase chain reaction analysis revealed that expression of THY1, PLZF, VASA, BCL6B, and UCHL1 as SCCs characteristic genes in THY1+ cells was significantly higher than in the initial population. Finally, transplantation of PKH26-labeled cells revealed that THY1+ cells had higher capacity for colony formation when compared with unselected cells. In conclusion, the results provide indications that THY1 surface marker can be reliably used for enrichment of undifferentiated spermatogonial in the goats.  相似文献   
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The aim of this study was to find the antifungal activities of seven essential oils from some Iranian medicinal plants that have maximum (100%) inhibition effect on the mycelium growth of postharvest phytopathogenic fungi. Among 20 examined species belonging to three families, only 7 species could stop the mycelium growth of phytopathogenic fungi. The selected plants include Trachyspermum ammi, Zataria multiflora Boiss., Satureia hortensis, Caryophillum aromaticus, Menthe piperita, Cuminum cyminum L. and Carum carvi, and fungi include Aspergillus flavus, Botrytis cinerea, Penicillium italicum, Penicillium expansum, Penicillium commune, Rhizopus stolonifer and Rhizopus lyococcus. The results showed that the essential oil of these plants could stop the mycelium growth at 500 ppm, but could not completely inhibit the spore germination, however reduced the spore germination to 80–90%. Among the fungi Rhizopus stolonifer and Rhizopus lyococcus are more resistant to the inhibition effects of essential oils. Among the plants, Cuminum cyminum L. and Carum carvi were slightly weaker than other plants. Also except for Cuminum cyminum L. and Carum carvi, the essential oils of other plants had fungicide effect while these two plants in most cases had fugistatic effect. The results showed that these essential oils can be used as an effective alternative control method.  相似文献   
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MicroRNAs are powerful gene expression regulators, but their corneal repertoire and potential changes in corneal diseases remain unknown. Our purpose was to identify miRNAs altered in the human diabetic cornea by microarray analysis, and to examine their effects on wound healing in cultured telomerase-immortalized human corneal epithelial cells (HCEC) in vitro. Total RNA was extracted from age-matched human autopsy normal (n=6) and diabetic (n=6) central corneas, Flash Tag end-labeled, and hybridized to Affymetrix® GeneChip® miRNA Arrays. Select miRNAs associated with diabetic cornea were validated by quantitative RT-PCR (Q-PCR) and by in situ hybridization (ISH) in independent samples. HCEC were transfected with human pre-miRTMmiRNA precursors (h-miR) or their inhibitors (antagomirs) using Lipofectamine 2000. Confluent transfected cultures were scratch-wounded with P200 pipette tip. Wound closure was monitored by digital photography. Expression of signaling proteins was detected by immunostaining and Western blot. Using microarrays, 29 miRNAs were identified as differentially expressed in diabetic samples. Two miRNA candidates showing the highest fold increased in expression in the diabetic cornea were confirmed by Q-PCR and further characterized. HCEC transfection with h-miR-146a or h-miR-424 significantly retarded wound closure, but their respective antagomirs significantly enhanced wound healing vs. controls. Cells treated with h-miR-146a or h-miR-424 had decreased p-p38 and p-EGFR staining, but these increased over control levels close to the wound edge upon antagomir treatment. In conclusion, several miRNAs with increased expression in human diabetic central corneas were found. Two such miRNAs inhibited cultured corneal epithelial cell wound healing. Dysregulation of miRNA expression in human diabetic cornea may be an important mediator of abnormal wound healing.  相似文献   
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The clearwing moth, Paranthrene diaphana Dalla Torre & Strand (Lep.: Sesiidae) is one of the most destructive pests of willow trees in Tehran province which leads to dieback. In this study, female volatile compounds were identified. For this purpose, female volatile substances were extracted using Solid Phase Micro Extraction and then were identified using Head Space Chromatography method. Female insects were assessed separately at ages of 2–4, 4–6 and 6–8 days of preparation. Among the various compounds identified by GC/MS in the volatile compounds of female insect, 27 compounds were introduced while seven combinations have also been produced and released at all ages of insect which include: Pentadecane, Heptadecane, Dodecane, Tetradecane, Hexadecane, Eicosane and Tridecane. The peak area of curve (log scale) and frequency of these compounds, demonstrate that five combinations including: Tetradecane, Hexadecane, Tridecane, Eicosane and Dodecane are more important. In addition, five compounds including: Octadecane, Palmitic acid (Hexadecanoic acid), 9-Octadecenoic acid, Tricosane and Hexacosane have been released only from fourth to the eighth day of adult life. Therefore, it seems that female sex pheromone is a combination of these 12 compounds.  相似文献   
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Reports have demonstrated occurrences of abnormalities in the early stages of chicken embryonic development due to the exposure to electromagnetic fields (EMFs). This article was designed to investigate the effects of sinusoidal EMF on the histopathology, apoptosis, and expressions of c-Fos and β-Catenin genes of the livers of preincubated White Leghorn chicken embryos, based on our published experiments. 300 healthy, fresh fertilized eggs were divided into control (n?=?70), sham (n?=?70), and four experimental (1-4,days 13, 14, 5, and 19, n?=?40) groups. Experimental eggs were exposed to the most effective intensity in a coil with 7.32?mT density, and sham groups were also located in the same coil with no exposure, both for 24?h before incubation. Control, sham, and experimental groups were then incubated in an incubator (37°C, humidity 60%) for 13,14,15, and 19 days. Livers of 13-15 and 19 day-old chicken embryos were removed by C-section and fixed in formalin (10%), stained with Hematoxylin-Eosin and TUNEL for histopathological and apoptosis studies. Others were used for investigating c-Fos and β-Catenin expressions, using RT-PCR. Results showed extensive hemorrhages all over the chicken embryos' bodies and livers, more lymphoid tissues, disturbed parenchymal tissues, sinusoid denaturation, vesiculizad cytoplasm, an increase in the number of apoptotic cells, and a decrease on the levels of expressions of c-Fos and β-Catenin genes in experimental groups of 1-4, comparing control and sham groups.  相似文献   
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The first and rate‐limiting step of the kynurenine pathway, in which tryptophan (Trp) is converted to N‐formylkynurenine is catalyzed by two heme‐containing proteins, Indoleamine 2,3‐dioxygenase (IDO), and Tryptophan 2,3‐dioxygenase (TDO). In mammals, TDO is found exclusively in liver tissue, IDO is found ubiquitously in all tissues. IDO has become increasingly popular in pharmaceutical research as it was found to be involved in many physiological situations, including immune escape of cancer. More importantly, small‐molecule inhibitors of IDO are currently utilized in cancer therapy. One of the main concerns for the design of human IDO (hIDO) inhibitors is that they should be selective enough to avoid inhibition of TDO. In this work, we have used a combination of classical molecular dynamics (MD) and hybrid quantum‐classical (QM/MM) methodologies to establish the structural basis that determine the differences in (a) the interactions of TDO and IDO with small ligands (CO/O2) and (b) the substrate stereo‐specificity in hIDO and TDO. Our results indicate that the differences in small ligand bound structures of IDO and TDO arise from slight differences in the structure of the bound substrate complex. The results also show that substrate stereo‐specificity of TDO is achieved by the perfect fit of L ‐Trp, but not D ‐Trp, which exhibits weaker interactions with the protein matrix. For hIDO, the presence of multiple stable binding conformations for L /D ‐Trp reveal the existence of a large and dynamic active site. Taken together, our data allow determination of key interactions useful for the future design of more potent hIDO‐selective inhibitors. Proteins 2010; © 2010 Wiley‐Liss, Inc.  相似文献   
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