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51.
Chick embryos grown in ex ovo culture by the modified Cornish pasty method reported in Nagai, Lin and Sheng in this issue.  相似文献   
52.
The chemical composition and in vitro antioxidant activity of the essential oil of propolis (EOP) collected from 25 locations in China was investigated. Steam‐distillation extraction was used to extract the EOP, and chemical composition was identified by GC/MS. The antioxidant activities of EOP were also measured. The result showed that a total of 406 compounds were detected in EOP. The major compounds of Chinese EOP were cedrol, γ‐eudesmol, benzyl alcohol, phenethyl alcohol, 2‐methoxy‐4‐vinylphenol, 3,4‐dimethoxystyrene and guaiol. Principal component analysis revealed the significant correlation between EOP compositions and their origins, and certain correlation was detected between EOP and their color. Linear discriminant analysis showed that 88 % and 84 % of the propolis samples were predicted correctly as the groupings identified by climatic zone and the color, respectively. Furthermore, the differences of antioxidant activities of EOP were significant. EOP of Shandong had the strongest antioxidant activities, whereas EOP of Guangdong, Yunnan and Hunan showed the poorest.  相似文献   
53.
International Journal of Peptide Research and Therapeutics - Immunotoxins are chimeric proteins that combine antibodies and toxins in targeted cancer therapy. Despite the promising application...  相似文献   
54.
Osteolytic skeletal disorders are caused by an imbalance in the osteoclast and osteoblast function. Suppressing the differentiation and resorptive function of osteoclast is a key strategy for treating osteolytic diseases. Dracorhodin perchlorate (D.P), an active component from dragon blood resin, has been used for facilitating wound healing and anti-cancer treatments. In this study, we determined the effect of D.P on osteoclast differentiation and function. We have found that D.P inhibited RANKL-induced osteoclast formation and resorbed pits of hydroxyapatite-coated plate in a dose-dependent manner. D.P also disrupted the formation of intact actin-rich podosome structures in mature osteoclasts and inhibited osteoclast-specific gene and protein expressions. Further, D.P was able to suppress RANKL-activated JNK, NF-κB and Ca2+ signalling pathways and reduces the expression level of NFATc1 as well as the nucleus translocation of NFATc1. Overall, these results indicated a potential therapeutic effect of D.P on osteoclast-related conditions.  相似文献   
55.
Although several genome‐wide association studies (GWAS) of non‐syndromic cleft lip with or without cleft palate (NSCL/P) have been reported, more novel association signals are remained to be exploited. Here, we performed an in‐depth analysis of our previously published Chinese GWAS cohort study with replication in an extra dbGaP case‐parent trios and another in‐house Nanjing cohort, and finally identified five novel significant association signals (rs11119445: 3’ of SERTAD4, P = 6.44 × 10−14; rs227227 and rs12561877: intron of SYT14, P = 5.02 × 10−13 and 2.80 × 10−11, respectively; rs643118: intron of TRAF3IP3, P = 4.45 × 10−6; rs2095293: intron of NR6A1, P = 2.98 × 10−5). The mean (standard deviation) of the weighted genetic risk score (wGRS) from these SNPs was 1.83 (0.65) for NSCL/P cases and 1.58 (0.68) for controls, respectively (P = 2.67 × 10−16). Rs643118 was identified as a shared susceptible factor of NSCL/P among Asians and Europeans, while rs227227 may contribute to the risk of NSCL/P as well as NSCPO. In addition, sertad4 knockdown zebrafish models resulted in down‐regulation of sox2 and caused oedema around the heart and mandibular deficiency, compared with control embryos. Taken together, this study has improved our understanding of the genetic susceptibility to NSCL/P and provided further clues to its aetiology in the Chinese population.  相似文献   
56.
Allopurinol (ALP) attenuates oxidative stress and diabetic cardiomyopathy (DCM), but the mechanism is unclear. Activation of nuclear factor erythroid 2‐related factor 2 (Nrf2) following the disassociation with its repressor Keap1 under oxidative stress can maintain inner redox homeostasis and attenuate DCM with concomitant attenuation of autophagy. We postulated that ALP treatment may activate Nrf2 to mitigate autophagy over‐activation and consequently attenuate DCM. Streptozotocin‐induced type 1 diabetic rats were untreated or treated with ALP (100 mg/kg/d) for 4 weeks and terminated after heart function measurements by echocardiography and pressure‐volume conductance system. Cardiomyocyte H9C2 cells infected with Nrf2 siRNA or not were incubated with high glucose (HG, 25 mmol/L) concomitantly with ALP treatment. Cell viability, lactate dehydrogenase, 15‐F2t‐Isoprostane and superoxide dismutase (SOD) were measured with colorimetric enzyme‐linked immunosorbent assays. ROS, apoptosis, was assessed by dihydroethidium staining and TUNEL, respectively. The Western blot and qRT‐PCR were used to assess protein and mRNA variations. Diabetic rats showed significant reductions in heart rate (HR), left ventricular eject fraction (LVEF), stroke work (SW) and cardiac output (CO), left ventricular end‐systolic volume (LVVs) as compared to non‐diabetic control and ALP improved or normalized HR, LVEF, SW, CO and LVVs in diabetic rats (all P < .05). Hearts of diabetic rats displayed excessive oxidative stress manifested as increased levels of 15‐F2t‐Isoprostane and superoxide anion production, increased apoptotic cell death and cardiomyocytes autophagy that were concomitant with reduced expressions of Nrf2, heme oxygenase‐1 (HO‐1) and Keap1. ALP reverted all the above‐mentioned diabetes‐induced biochemical changes except that it did not affect the levels of Keap1. In vitro, ALP increased Nrf2 and reduced the hyperglycaemia‐induced increases of H9C2 cardiomyocyte hypertrophy, oxidative stress, apoptosis and autophagy, and enhanced cellular viability. Nrf2 gene silence cancelled these protective effects of ALP in H9C2 cells. Activation of Nrf2 subsequent to the suppression of Keap1 and the mitigation of autophagy over‐activation may represent major mechanisms whereby ALP attenuates DCM.  相似文献   
57.
Lithium–sulfur batteries (LSBs) are considered promising candidates for the next‐generation energy‐storage systems due to their high theoretical capacity and prevalent abundance of sulfur. Their reversible operation, however, encounters challenges from both the anode, where dendritic and dead Li‐metal form, and the cathode, where polysulfides dissolve and become parasitic shuttles. Both issues arise from the imperfection of interphases between electrolyte and electrode. Herein, a new lithium salt based on an imide anion with fluorination and unsaturation in its structure is reported, whose interphasial chemistries resolve these issues simultaneously. Lithium 1, 1, 2, 2, 3, 3‐hexafluoropropane‐1, 3‐disulfonimide (LiHFDF) forms highly fluorinated interphases at both anode and cathode surfaces, which effectively suppress formation of Li‐dendrites and dissolution/shuttling of polysulfides, and significantly improves the electrochemical reversibility of LSBs. In a broader context, this new Li salt offers a new perspective for diversified beyond Li‐ion chemistries that rely on a Li‐metal anode and active cathode materials.  相似文献   
58.
Tian  Suyan  Zhu  Xuetong  Sun  Xuejuan  Wang  Jinmei  Zhou  Qi  Wang  Chi  Chen  Li  Li  Shanji  Xu  Jiancheng 《中国病毒学》2020,35(6):811-819
Virologica Sinica - The temporal change patterns of laboratory data may provide insightful clues into the whole course of COVID-19. This study aimed to evaluate longitudinal change patterns of key...  相似文献   
59.
本研究通过比较9个内参基因在山羊不同组织中的表达水平进而确定最适合研究山羊组织表达的内参基因。本试验以简州大耳羊为试验材料,利用实时荧光定量PCR技术分析9个内参基因(GAPDH,PPIA,18S rRNA,PPIB,UXT,RPLP0,ACTB,EIF3K和TBP)在心脏、肝脏、脾脏、肺脏、肾脏、大肠、瘤胃、背最长肌和皮下脂肪等组织中的表达差异情况,并利用geNorm、NormFinder和BestKeeper等程序分析了它们的表达稳定性。geNorm和NormFinder程序一致显示TBP表达最稳定,其次是UXT和RPLP0;BestKeeper分析显示18S rRNA表达最为稳定,其次为TBP和ACTB;3个程序一致认为GAPDH表达稳定性最差。综合3个程序分析得出TBP最适合作为山羊组织中的内参基因,其次为UXT和RPLP0,GAPDH表达稳定性最差,不适合作为山羊组织内参,这为后续研究其他目的基因在山羊组织器官中的表达模式提供数据保障。  相似文献   
60.
Changes in mitochondrial dynamics (fusion and fission) are known to occur during stem cell differentiation; however, the role of this phenomenon in tissue aging remains unclear. Here, we report that mitochondrial dynamics are shifted toward fission during aging of Drosophila ovarian germline stem cells (GSCs), and this shift contributes to aging‐related GSC loss. We found that as GSCs age, mitochondrial fragmentation and expression of the mitochondrial fission regulator, Dynamin‐related protein (Drp1), are both increased, while mitochondrial membrane potential is reduced. Moreover, preventing mitochondrial fusion in GSCs results in highly fragmented depolarized mitochondria, decreased BMP stemness signaling, impaired fatty acid metabolism, and GSC loss. Conversely, forcing mitochondrial elongation promotes GSC attachment to the niche. Importantly, maintenance of aging GSCs can be enhanced by suppressing Drp1 expression to prevent mitochondrial fission or treating with rapamycin, which is known to promote autophagy via TOR inhibition. Overall, our results show that mitochondrial dynamics are altered during physiological aging, affecting stem cell homeostasis via coordinated changes in stemness signaling, niche contact, and cellular metabolism. Such effects may also be highly relevant to other stem cell types and aging‐induced tissue degeneration.  相似文献   
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