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81.
Chen SJ  Fan J  Jiang QY  Lan GQ  Guo XP  Guo YF 《遗传》2012,34(4):445-453
To investigate the functions of U6 and 7SK of Bama mini-pig and produce Bama mini-pig with silenced GGTA1 gene, the siRNA promoters U6 and 7SK were cloned, ligated into pMD18-shEGFP, and co-transfected with PEGFP- N1 into PK-15 kidney cells of pigs to be used in RNAi experiments. The functions of the two promoters in pig cells were verified using pMD18-hU6-shEGFP as the positive control, pMD18-shEGFP vector without promoter as the negative control, PEGFP-N1 as the first blank control, ddH2O in replacement of the plasmid as the second blank control. The results showed that the lengths of U6 and 7SK in Bama mini-pig were 553 bp and 437 bp, respectively. Vectors pMD18-pU6- shEGFP and pMD18-p7SK-shEGFP were constructed and transfected into PK-15 cells from pigs. Promoters pU6 and p7SK proved to express high levels of siRNA activity and can be used in the experiment of silencing α-1,3galactosyltransferase gene.  相似文献   
82.
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked hereditary disease that predisposes red blood cells to oxidative damage. G6PD deficiency is particularly prevalent in historically malaria-endemic areas. Use of primaquine for malaria treatment may result in severe hemolysis in G6PD deficient patients. In this study, we systematically evaluated the prevalence of G6PD deficiency in the Kachin (Jingpo) ethnic group along the China-Myanmar border and determined the underlying G6PD genotypes. We surveyed G6PD deficiency in 1770 adult individuals (671 males and 1099 females) of the Kachin ethnicity using a G6PD fluorescent spot test. The overall prevalence of G6PD deficiency in the study population was 29.6% (523/1770), among which 27.9% and 30.6% were males and females, respectively. From these G6PD deficient samples, 198 unrelated individuals (147 females and 51 males) were selected for genotyping at 11 known G6PD single nucleotide polymorphisms (SNPs) in Southeast Asia (ten in exons and one in intron 11) using a multiplex SNaPshot assay. Mutations with known association to a deficient phenotype were detected in 43.9% (87/198) of cases, intronic and synonymous mutations were detected alone in 34.8% (69/198) cases and no mutation were found in 21.2% (42/198) cases. Five non-synonymous mutations, Mahidol 487G>A, Kaiping 1388G>A, Canton 1376G>T, Chinese 4 392G>T, and Viangchan 871G>A were detected. Of the 87 cases with known deficient mutations, the Mahidol variant was the most common (89.7%; 78/87), followed by the Kaiping (8.0%; 7/87) and the Viangchan (2.2%; 2/87) variants. The Canton and Chinese 4 variants were found in 1.1% of these 87 cases. Among them, two females carried the Mahidol/Viangchan and Mahidol/Kaiping double mutations, respectively. Interestingly, the silent SNPs 1311C>T and IVS11nt93T>C both occurred in the same 95 subjects with frequencies at 56.4% and 23.5% in tested females and males, respectively (P<0.05). It is noteworthy that 24 subjects carrying the Mahidol mutation and two carrying the Kaiping mutation also carried the 1311C>T/IVS11nt93T>C SNPs. Further studies are needed to determine the enzyme levels of the G6PD deficient people and presence of additional G6PD mutations in the study population.  相似文献   
83.
84.
MicroRNAs (miRNAs) have been established to regulate skeletal muscle development in mammals. However, few studies have been conducted on the regulation of proliferation and differentiation of bovine myoblast cells by miRNAs. The aim of our study was to explore the function of miR-483 in cell proliferation and differentiation of bovine myoblast. Here, we found that miR-483 declined in both proliferation and differentiation stages of bovine myoblast cells. During the proliferation phase, the overexpression of miR-483 downregulated the cell cycle–associated genes cyclin-dependent kinase 2 (CDK2), proliferating cell nuclear antigen (PCNA) messenger RNA (mRNA), and the protein levels. At the cellular level, cell cycle, cell counting kit-8, and 5-ethynyl-2´-deoxyuridine results indicated that the overexpression of miR-483 block cell proliferation. During differentiation, the overexpression of miR-483 led to a decrease in the levels of the myogenic marker genes MyoD1 and MyoG mRNA and protein. Furthermore, the immunofluorescence analysis results showed that the number of MyHC-positive myotubes was reduced. In contrast, the opposite experimental results were obtained concerning both proliferation and differentiation after the inhibition of miR-483. Mechanistically, we demonstrated that miR-483 target insulin-like growth factor 1 (IGF1) and downregulated the expression of key proteins in the PI3K/AKT signaling pathway. Altogether, our findings indicate that miR-483 acts as a negative regulator of bovine myoblast cell proliferation and differentiation.  相似文献   
85.
 细菌(Pseudomonas moltophilia)与hCG及LH有特异的亲和力,实验发现,细菌之生长曲线与hCG结合活性成平行关系,96小时达高峰,细菌之培养液中含有可溶性结合蛋白,该蛋白经硫酸铵沉淀(80%饱和度)、Sephadex G-100柱层析、DEAE-纤维素柱0.5mol/L NaCl梯度洗脱,再过Sepharose CL-AB柱,收集之活性部分经SDS电泳测得其分子量为70,000,凝胶层析测Stokes radius为41A,Schiff氏染色未见着色带。  相似文献   
86.
Abrupt drought–flood alternation (T1) is a meteorological disaster that frequently occurs during summer in southern China and the Yangtze river basin, often causing a significant loss of rice production. In this study, the response mechanism of yield decline under abrupt drought–flood alternation stress at the panicle differentiation stage was analyzed by looking at the metabolome, proteome as well as yield and physiological and biochemical indexes. The results showed that drought and flood stress caused a decrease in the yield of rice at the panicle differentiation stage, and abrupt drought–flood alternation stress created a synergistic effect for the reduction of yield. The main reason for the decrease of yield per plant under abrupt drought–flood alternation was the decrease of seed setting rate. Compared with CK0 (no drought and no flood), the net photosynthetic rate and soluble sugar content of T1 decreased significantly and its hydrogen peroxidase, superoxide dismutase, peroxidase activity increased significantly. The identified differential metabolites and differentially expressed proteins indicated that photosynthesis metabolism, energy metabolism pathway and reactive oxygen species response have changed strongly under abrupt drought–flood alteration stress, which are factors that leads to the rice grain yield reduction.  相似文献   
87.
Neurofibromatosis type-1 (NF1) patients suffer from cutaneous and subcutaneous neurofibromas (CNF) and large plexiform neurofibromas (PNF). Whole gene deletions of the NF1 gene can cause a more severe phenotype compared to smaller intragenic changes. Two distinct groups of NF1 whole gene deletions are type-1 deletions and atypical deletions. Our aim was to assess volumes and averaged annual growth-rates of CNF and PNF in patients with NF1 whole gene deletions and to compare these with NF1 patients without large deletions of the NF1 gene.We retrospectively evaluated 140 whole-body MR examinations of 38 patients with NF1 whole gene deletions (type-1 group: n = 27/atypical group n = 11) and an age- and sex matched collective of 38 NF1-patients. Age-dependent subgroups were created (0–18 vs >18 years). Sixty-four patients received follow-up MRI examinations (NF1whole gene deletion n = 32/control group n = 32). Whole-body tumor-volumes were semi-automatically assessed (MedX, V3.42). Tumor volumes and averaged annual growth-rates were compared.Median tumor-burden was significantly higher in the type-1 group (418ml; IQR 77 – 950ml, p = 0.012) but not in the atypical group (356ml;IQR 140–1190ml, p = 0.099) when compared to the controls (49ml; IQR 11–691ml). Averaged annual growth rates were significantly higher in both the type-1 group (14%/year; IQR 45–36%/year, p = 0.004) and atypical group (11%/year; IQR 5–23%/year, p = 0.014) compared to the controls (4%/year; IQR1–8%/year). Averaged annual growth rates were significantly higher in pediatric patients with type-1 deletions (21%/year) compared with adult patients (8%/year, p = 0.014) and also compared with pediatric patients without large deletions of the NF1 gene (3.3%/year, p = 0.0015).NF1 whole gene deletions cause a more severe phenotype of NF1 with higher tumor burden and higher growth-rates compared to NF1 patients without large deletions of the NF1 gene. In particular, pediatric patients with type-1 deletions display a pronounced tumor growth.  相似文献   
88.
目的了解Wistar大鼠心脏自发性病变发病情况,为长期致癌性研究、老年病学研究及毒性病理学提供背景资料。方法采用160只清洁级Wistar大鼠,雌雄各半,常规饲养,分别在9月龄、12月龄、18月龄、24月龄时处死40只大鼠,HE及Masson三色法染色,观察心脏的病理改变。结果 9月龄Wistar大鼠心脏未见明显病理改变;12月龄Wistar大鼠月龄心脏病变的发病率为2.5%(1/40),表现为少数心肌细胞变性坏死伴少量以单核细胞为主的炎细胞浸润;18月龄大鼠心脏病变的发病率为57.5%(23/40),表现为轻至中度心肌病,雄性发病率高于雌性。24月龄大鼠100%(40/40)出现不同程度的心肌病,并有2.5%(1/40)发生心内膜下纤维组织增生。Masson染色显示9月龄大鼠心脏血管周围及心脏瓣膜环下有少量胶原纤维,随年龄增长,血管周围及心脏瓣膜环下胶原纤维逐渐增多,并延伸入心肌细胞间。结论随年龄增长,大鼠心脏自发病变比率升高,主要病变为心肌病,偶尔可发生心内膜下纤维组织增生;胶原纤维沉积首先发生于血管周围及心脏瓣膜环下,随年龄增长而增多,可能与大鼠心肌病的的发生密切相关。  相似文献   
89.
An ecosystem service is a benefit derived by humanity that can be traced back to an ecological process. Although ecosystem services related to surface water have been thoroughly described, the relationship between atmospheric water and ecosystem services has been mostly neglected, and perhaps misunderstood. Recent advances in land-atmosphere modeling have revealed the importance of terrestrial ecosystems for moisture recycling. In this paper, we analyze the extent to which vegetation sustains the supply of atmospheric moisture and precipitation for downwind beneficiaries, globally. We simulate land-surface evaporation with a global hydrology model and track changes to moisture recycling using an atmospheric moisture budget model, and we define vegetation-regulated moisture recycling as the difference in moisture recycling between current vegetation and a hypothetical desert world. Our results show that nearly a fifth of annual average precipitation falling on land is from vegetation-regulated moisture recycling, but the global variability is large, with many places receiving nearly half their precipitation from this ecosystem service. The largest potential impacts for changes to this ecosystem service are land-use changes across temperate regions in North America and Russia. Likewise, in semi-arid regions reliant on rainfed agricultural production, land-use change that even modestly reduces evaporation and subsequent precipitation, could significantly affect human well-being. We also present a regional case study in the Mato Grosso region of Brazil, where we identify the specific moisture recycling ecosystem services associated with the vegetation in Mato Grosso. We find that Mato Grosso vegetation regulates some internal precipitation, with a diffuse region of benefit downwind, primarily to the south and east, including the La Plata River basin and the megacities of Sao Paulo and Rio de Janeiro. We synthesize our global and regional results into a generalized framework for describing moisture recycling as an ecosystem service. We conclude that future work ought to disentangle whether and how this vegetation-regulated moisture recycling interacts with other ecosystem services, so that trade-offs can be assessed in a comprehensive and sustainable manner.  相似文献   
90.
本文采用苏制核微孔滤膜进行了除菌、除支原体实验研究,核孔膜孔径分别为0.07、0.1、0.5、0.7及1.5微米,采用的菌种为白色葡萄球菌、链球菌和大肠杆菌,支原体为解脲脲原体,实验结果表明:0.07及0.1微米的核孔膜可完全滤除细菌及支原体,0.5微米的核孔膜可滤除绝大部分细菌,不能滤除支原体,1.5微米的核孔膜只能滤除少量细菌。  相似文献   
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