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931.
V. A. Efimov A. A. Buryakova N. N. Polushin I. Y. Dubey O. G. Chakhmakhcheva Yu. A. Ovchinnikov 《Nucleosides, nucleotides & nucleic acids》2013,32(1-2):279-282
Abstract An effective method for the synthesis of oligonucleotides by the phosphotriester approach has been developed. It is based on the use of phosphate protecting groups enabling O-nucleophilic intramolecular catalysis. 相似文献
932.
933.
C. WARNER B. GERNDT Y. XU Y. BOURLET C. AUFFRAY S. LAMONT† A. NORDSKOG† 《Animal genetics》1989,20(3):225-231
Summary. High molecular weight DNA was extracted from sperm from chickens of 14 inbred lines. The DNA was digested with each of four restriction enzymes ( Pvu II, Hind III, Bg /II, and Bam HI), electrophoresed for 18 or 45h, blotted onto nitrocellulose, and hybridized to a chicken major histocompatibility complex (MHC, B complex) class II β-chain probe (β2-exon specific). Restriction fragment length polymorphisms (RFLPs) were found with each of the restriction enzymes used. Birds with the same B haplotype always showed the same RFLP pattern; however, some birds of different B halotypes also shared the same RFLP pattern. To test for the Mendelian inheritance of the RFLP patterns, the F2 progeny of an informative cross were analysed. The RFLP patterns corresponded with the serologically determined B haplotypes of the F2 birds, thereby showing the Mendelian inheritance of the polymorphic bands. 相似文献
934.
The results of studies on the axial skeleton of the common toad (a model species) have been used to analyze factual limitations of individual variation. The results show that the states of the studied characters do not freely combine with each other but are subject to certain morphogenetic limitations. The causes of most these limitations have been revealed during the study. Classification of the main factors limiting individual variation in the course of development is presented. 相似文献
935.
Yao He Hui Xu Zichao Xiang Hongyou Yu Li Xu Yongwen Guo Ye Tian Rui Shu Xianrui Yang Chaoran Xue Mengyuan Zhao Yiruo He Xianglong Han Ding Bai 《Journal of cellular physiology》2019,234(4):5086-5096
During orthodontic tooth movement (OTM), periodontal ligament cells (PDLCs) receive the mechanical stimuli and transform it into myofibroblasts (Mfbs). Indeed, previous studies have demonstrated that mechanical stimuli can promote the expression of Mfb marker α-smooth muscle actin (α-SMA) in PDLCs. Transforming growth factor β1 (TGF-β1), as the target gene of yes-associated protein (YAP), has been proven to be involved in this process. Here, we sought to assess the role of YAP in Mfbs differentiation from PDLCs. The time-course expression of YAP and α-SMA was manifested in OTM model in vivo as well as under tensional stimuli in vitro. Inhibition of RhoA/Rho-associated kinase (ROCK) pathway using Y27632 significantly reduced tension-induced Mfb differentiation and YAP expression. Moreover, overexpression of YAP with lentiviral transfection in PDLCs rescued the repression effect of Mfb differentiation induced by Y27632. These data together suggest a crucial role of YAP in regulating tension-induced Mfb differentiation from PDLC interacted with RhoA/ROCK pathway. 相似文献
936.
The NLR (nucleotide-binding domain leucine-rich repeat containing) proteins serve as regulators of inflammatory signaling pathways. NLRX1, a mitochondria-localized NLR protein, has been previously shown to negatively regulate inflammatory cytokine production activated via the MAVS-DDX58 (RIG-I) pathway. The literature also indicates that DDX58 has a negative impact upon autophagy. Consistent with the inhibitory role of NLRX1 on DDX58, our recent study indicates a role of NLRX1 in augmenting virus-induced autophagy. This effect is through its interaction with another mitochondrial protein TUFM (Tu translation elongation factor, mitochondrial, also known as EF-TuMT, COXPD4, and P43). TUFM also reduces DDX58-activated cytokines but augments autophagy. Additionally it interacts with ATG12–ATG5-ATG16L1 to form a molecular complex that modulates autophagy. The work shows that both NLRX1 and TUFM work in concert to reduce cytokine response and augment autophagy. 相似文献
937.
Zhihui Deng Jianxin Zhen Genelle F Harrison Guobin Zhang Rui Chen Ge Sun Qiong Yu Neda Nemat-Gorgani Lisbeth A Guethlein Liumei He Mingzhong Tang Xiaojiang Gao Siqi Cai William H Palmer Jonathan A Shortt Christopher R Gignoux Mary Carrington Hongyan Zou Peter Parham Wenxu Hong Paul J Norman 《Molecular biology and evolution》2021,38(6):2582
Human natural killer (NK) cells are essential for controlling infection, cancer, and fetal development. NK cell functions are modulated by interactions between polymorphic inhibitory killer cell immunoglobulin-like receptors (KIR) and polymorphic HLA-A, -B, and -C ligands expressed on tissue cells. All HLA-C alleles encode a KIR ligand and contribute to reproduction and immunity. In contrast, only some HLA-A and -B alleles encode KIR ligands and they focus on immunity. By high-resolution analysis of KIR and HLA-A, -B, and -C genes, we show that the Chinese Southern Han (CHS) are significantly enriched for interactions between inhibitory KIR and HLA-A and -B. This enrichment has had substantial input through population admixture with neighboring populations, who contributed HLA class I haplotypes expressing the KIR ligands B*46:01 and B*58:01, which subsequently rose to high frequency by natural selection. Consequently, over 80% of Southern Han HLA haplotypes encode more than one KIR ligand. Complementing the high number of KIR ligands, the CHS KIR locus combines a high frequency of genes expressing potent inhibitory KIR, with a low frequency of those expressing activating KIR. The Southern Han centromeric KIR region encodes strong, conserved, inhibitory HLA-C-specific receptors, and the telomeric region provides a high number and diversity of inhibitory HLA-A and -B-specific receptors. In all these characteristics, the CHS represent other East Asians, whose NK cell repertoires are thus enhanced in quantity, diversity, and effector strength, likely augmenting resistance to endemic viral infections. 相似文献
938.
O. I. Iatsyna E. O. Stakhovsky Ya. A. Sheremet S. I. Spivak O. E. Stakhovsky O. N. Gavrilyuk Yu. V. Vitruk A. I. Emets Ya. B. Blyum S. V. Vernygorodskyi 《Cytology and Genetics》2011,45(4):201-207
The TUNEL reaction was used to study induced apoptosis in the tumor cells of urinary bladder cancer (UBC) patients. It has
been shown that an increase in the values of induced apoptosis correlates well with the indicators showing a tumor’s corresponding
response to the application of neoadjuvant chemotherapy, using the gemcitabine-cisplatin regimen. It has been concluded that
assessing the level of induced apoptosis in UBC tumor cells using the TUNEL assay enables making a prognosis for the efficacy
of chemotherapy at the single-cell level in patients with this type of cancer. 相似文献
939.
Food restriction (FR) is hypothesized to decrease body fat content of an animal and thus prevent obesity. However, the response
of energy budget to a continuous (CFR) or discontinuous FR (DFR) remains inconsistent. In the present study, effects of CFR
or DFR and refeeding on energy budget and behavior were examined in male Swiss mice. CFR significantly decreased the energy
expenditure associated with basal metabolic rate (BMR) and activity behavior, but not sufficiently to compensate for energy
deficit and thus resulted in lower body mass and fat content. DFR mice had a significantly higher food intake on ad libitum
days and showed increases in BMR and activity after 4 weeks’ DFR, which might resulted in lower body mass and less body fat
than controls. After being refed ad libitum, both CFR and DFR mice had similar body mass, BMR, and behavioral patterns to
controls but had 95% and 75% higher fat content. This suggested that not only CFR but also DFR would be a significant factor
in the process of obesity for animals that were refed ad libitum. It also indicated that food restriction interrupted many
times by periods of ad libitum feeding had the same long-term effects like continuous underfeeding. 相似文献
940.
Human Physiology - Training of impaired motor functions forms activity-dependent plasticity aimed to compensate the functional deficiency. In individuals with chronic motor-complete spinal cord... 相似文献