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11.
Studies on hemoglobin variants in Korean cattle   总被引:1,自引:0,他引:1  
814 hemoglobin samples from Korean cattle were investigated by starch gel electrophoresis for the detection of hemoglobin variants. A new variant of cattle hemoglobin, called Hb, H, was recognized. It has a slower rate of migration than Hb A.
Hemoglobin types from 814 Korean cattle were as follows: 652 of Hb AA type (80.1 %), 133 of Hb AB (16.4 %), 12 of Hb AC (1.5 %), 9 of Hb BB (1.1 %), 2 of Hb BC (0.2 %), 4 of Hb AH (0.5 %), 1 of Hb CH (0.1 %), 1 of Hb HH (0.1 %). These figures correspond to the frequencies: HbA = 0.893, HbB = 0.093, Hbc =0.009, HbH = 0.004.
Gene frequencies at the Hb locus in Korean cattle were compared among six population from different provinces. Generally, high frequencies of HbA were observed in each province.  相似文献   
12.
The possibility of preventing the transmission of porcine endogenous retrovirus (PERV) to human cells using short interfering RNAs (siRNA) was investigated. The siRNA for the p30 of PERV gag region was cloned into pSUPER, the polymerase-III H1-RNA gene promoter. A green fluorescence protein (GFP) was also cloned into pSUPER to establish pSXGH. Pig endothelial cells (PEC) were transduced with the LacZ gene by pseudotype infection, and infected with PERV subtype B, resulting in the formation of PEC(LacZ)/PB. The PEC(LacZ)/PB was next transfected with pSXGH-siRNA. The expression of siRNA was provisionally checked by determining the level of expression of GFP. Culture supernatants of infected cells were then inoculated into HEK293 cells. The siRNA clearly destroyed the PERV infectivity of PEC(LacZ)/PB in both transient cell lines and stable clones. Moreover, the decreased levels of mRNA and gag protein were evidenced in the stable clones by real-time PCR and Western blotting, respectively. The final goal of our study was to establish a transgenic pig expressing the siRNA for PERV. The results suggest that siRNA represents a novel approach for controlling PERV infections in clinical xenotransplantation.  相似文献   
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The small subunit of ribulose-bisphosphate carboxylase (Rubisco), encoded by rbcS, is essential for photosynthesis in both C3 and C4 plants, even though the cell specificity of rbcS expression is different between C3 and C4 plants. The C3 rbcS is specifically expressed in mesophyll cells, while the C4 rbcS is expressed in bundle sheath cells, and not mesophyll cells. Two chimeric genes were constructed consisting of the structural gene encoding -glucuronidase (GUS) controlled by the two promoters from maize (C4) and rice (C3) rbcS genes. These constructs were introduced into a C4 plant, maize. Both chimeric genes were specifically expressed in photosynthetic organs, such as leaf blade, but not in non-photosynthetic organs. The expressions of the genes were also regulated by light. However, the rice promoter drove the GUS activity mainly in mesophyll cells and relatively low in bundle sheath cells, while the maize rbcS promoter induced the activity specifically in bundle sheath cells. These results suggest that the rice promoter contains some cis-acting elements responding in an organ-pecific and light-inducible regulation manner in maize but does not contain element(s) for bundle sheath cell-specific expression, while the maize promoter does contain such element(s). Based on this result, we discuss the similarities and differences between the rice (C3) and maize (C4) rbcS promoter in terms of the evolution of the C4 photosynthetic gene.  相似文献   
15.
The operon encoding ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) in the cyanobacterium Synechococcus sp. PCC7002 contains three rbc genes, rbcL, rbcX and rbcS, in this order. Introduction of translational frameshift into the rbcX gene resulted in a significant decrease in the production of large (RbcL) and small (RbcS) subunits of the Rubisco protein in Synechococcus sp. PCC7002 and in Escherichia coli. To investigate the function of the rbcX gene product (RbcX), we constructed the expression plasmid for the rbcX gene and examined the effects of RbcX on the recombinant Rubisco production in Escherichia coli. The coexpression experiments revealed that RbcX had marked effects on the production of large and small subunits of Rubisco without any significant influence on the mRNA level of rbc genes and/or the post-translational assembly of the Rubisco protein. The present rbcX coexpression system provides a novel and useful method for investigating the Rubisco maturation pathway.  相似文献   
16.
The abilities of 15 flavonoids as a scavenger of active oxygens (hydroxyl radical and superoxide anion) were studied. Hydroxyl radical (.OH) was generated by the Fenton system, and assayed by the determination of methanesulfinic acid (MSA) formed from the reaction of dimethyl sulfoxide (DMSO) with .OH. (+)-Catechin, (−)-epicatechin, 7,8-dihydroxy flavone, and rutin showed the .OH scavenging effect 100–300 times superior to that of mannitol, a typical .OH scavenger. The other flavonoids showed no .OH scavenging effect at their concentrations up to 50 μM. Baicalein, quercetin, morin, and myricetin unexpectedly increased the .OH production in the Fenton system. The flavonoids tested now, except monohydroxy flavones, were more or less inhibitive to the superoxide anion (O2) generation in the hypoxanthine-xanthine oxidase system. A great part of this inhibitory effect was likely owing to suppression of xanthine oxidase activity by the flavonoids. The flavonoids, which scavenged .OH or O2, were necessarily antioxidants to the peroxidation of methyl linoleate. However, there was a type of flavonoid such as morin, which have neither .OH nor O2 scavenging effect, but was a strong antioxidant.  相似文献   
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18.
The effect of human platelet functions of 9,11-dithio analogues of prostaglandin endoperoxide was investigated. Methyl (5z,9α,11α,13e,15S)-9,11-epidithio-15-hydroxyprosta- 5,13-dienoate induced platelet aggregation, while the 9β,11β-epimer was inactive. The platelet aggregation caused by the 9α,11α-dithio analogue was associated with serotonin release from platelets, and was inhibited by methyl ester of prostaglandin I2 (prostacyclin) but not by indomethacin.  相似文献   
19.
Enzyme(s) capable of decomposing N-acetylglucosaminyl ribitol teichoic acid prepared from the cell wall of Staphylococcus aureus FDA 209 P was obtained from the culture supernatant of a gram-negative, rod-shaped, spore-forming soil bacterium. Properties of the bacterium were very similar to those of Bacillus circulans.  相似文献   
20.

Urban waterlogging stems from coverage with impervious surfaces and increasing rainfall intensity from climate change and variability, meaning that storm water cannot readily infiltrate the ground and excessive surface runoff leads to urban flooding. To reduce related environmental and safety risks, rainfall and groundwater level research was carried out in Kyoto Prefecture with two rain gardens (RG1 and RG2) to investigate flood mitigation functions using a tank model. During the 134 days of monitoring from July 14, 2017, to November 25, 2017, RG1 had seven overflow events with an average runoff control ratio of 63.94%, and RG2 had one event with a ratio of 95.97%. The RG1 tank model (two stages) showed that initial storage for the first and second depths was 6.912?×?10?11 and 0 mm, respectively. The heights of the discharge holes were 20.857 and 0.784 mm for the first stage and 0.659 mm for the second stage, and the discharge hole coefficients were 0.529 and 0.002 for the first stage and 0.004 for the second stage. The results showed that RG1 had penetration hole coefficients of 0.138 (first stage) and 0.254 (second stage), with a water balance error of 0.017 (<?0.02) and a Nash–Sutcliffe efficiency coefficient of 0.922, indicating better reliability and quality than RG2 with the one-stage tank model. Peak flow simulation for mitigation showed that RG1 had a high overflow control ratio (mitigation time 2 h for instant rainfall of 100 mm/h), and can therefore be considered appropriate for other urban areas of Japan.

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