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151.
The purpose of the present study was to examine the effect of maximal arm exercise on the skin blood circulation of the paralyzed lower limbs in persons with spinal cord injury (PSCI). Eight male PSCI with complete lesions located between T3 and L1 performed graded maximal arm-cranking exercise (MACE) to exhaustion. The skin blood flux at the thigh (SBFT) and that at the calf (SBFC) were monitored using laser-Doppler flowmeter at rest and for 15 s immediately after the MACE. The subject's mean peak oxygen uptake and peak heart rate was 1.41 ± 0.22 1·min−1 and 171.6 ± 19.2 beats·min−1, respectively. No PSCI showed any increase in either SBFT or SBFC after the MACE, when compared with the values at rest. These results suggest that the blood circulation of the skin in the paralyzed lower limbs in PSCI is unaffected by the MACE.  相似文献   
152.
A peptidoglutaminase activity in microorganisms was detected using carbobenzoxy-l-glutamine or tertiary-amyloxycarbonyl-l-glutaminyl-l-proline as substrate. By screening, an organism which produces a relatively large amount of peptidoglutaminase was isolated from soil. The organism was identified as Bacillus circulans. The highest enzyme formation by the bacterium occurred during stationary growth phase in the basal medium containing lactose (0.5%) and polypepton (1%).  相似文献   
153.
DNA complementary to mRNA of human immunoglobulin E heavy chain (epsilon chain) isolated and purified from U266 cells has been synthesized and inserted into the PstI site of pBR322 by G-C tailing. This recombinant plasmid was used to transform E. coli chi 1776 to screen 1445 tetracycline resistant colonies. Nine clones (pGETI - 9) containing cDNA coding for the human epsilon chain were recognized by colony hybridization and Southern blotting analysis with a nick-translated human IgE genome fragment. The nucleotide sequence of the longest cDNA contained in pGET2 was determined. The results indicate that the sequence of 1657 nucleotides codes for 494 amino acids covering a part of the variable region and all of the constant region of the human epsilon chain. Most of the amino acid sequence deduced from the nucleotide sequence is in substantial agreement with that reported. Furthermore a termination codon after the -COOH terminal amino acid marks the beginning of a 3' untranslated region of 125 nucleotides with a poly A tail. Taking this into account, the structure of the human epsilon chain mRNA, except a part of the 5' end, is conserved fairly well in the cDNA insert in pGET2.  相似文献   
154.
The insertion of light-harvesting chlorophyll proteins (LHCPs) into the thylakoid membrane of the chloroplast is cpSRP-dependent, and requires the stromal components cpSRP54 and cpSRP43, the membrane-bound SRP receptor cpFtsY and the integral membrane protein Alb3. Previous studies demonstrated that the Arabidopsis mutant lacking both cpSRP54 and cpSRP43 had pale yellow leaves, but was viable, whereas the mutants lacking Alb3 exhibit an albino phenotype that is more severe and seedling lethality. We previously showed that a maize mutant lacking cpFtsY had a pale yellow-green phenotype and was seedling lethal. To compare the in vivo requirements of cpFtsY and Alb3 in thylakoid biogenesis in greater detail, we isolated Arabidopsis null mutants of cpftsY, and performed biochemical comparisons with the Arabidopsis alb3 mutant. Both cpftsY and alb3 null mutants were seedling lethal on a synthetic medium lacking sucrose, whereas on a medium supplemented with sucrose, they were able to grow to later developmental stages, but were mostly infertile. cpftsY mutant plants had yellow leaves in which the levels of LHCPs were reduced to 10-33% compared with wild type. In contrast, alb3 had yellowish white leaves, and the LHCP levels were less than or equal to 10% of those of wild type. Intriguingly, whereas accumulation of the Sec and Tat machineries were normal in both mutants, the Sec pathway substrate Cyt f was more severely decreased in the cpftsY mutant than in alb3, which may indicate a functional link between cpFtsY and Sec translocation machinery. These results suggest that cpFtsY and Alb3 have essentially similar, but slightly distinct, contributions to thylakoid biogenesis.  相似文献   
155.
To elucidate the function of protein disulfide isomerase (PDI), we screened for PDI-binding proteins in a bovine liver extract using affinity column chromatography. One of the binding proteins was identified by SDS-PAGE and N-terminal amino acid sequence analysis to be cyclophilin B (Cyp B). Use of the BIACORE system revealed that purified bovine Cyp B bound specifically to bovine PDI with a K(D) value of 1.19 x 10(-5) M. Interestingly, the binding affinity between PDI and Cyp B was strengthened by preincubation of the Cyp B with cyclosporin A (CsA), yielding a K(D) value of 3.67 x 10(-6) M. Although the interaction between PDI and Cyp B affected neither the isomerase activity of PDI nor the peptidyl-prolyl cis-trans isomerase activity of Cyp B, Cyp B increased the chaperone activity of PDI. However, the complex of Cyp B and CsA completely inhibited the chaperone activity of PDI. Thus, PDI and Cyp B appear to cooperate with each other to regulate the functional expression of proteins in vivo.  相似文献   
156.
Structures of sugar chains of the third component of human complement   总被引:2,自引:0,他引:2  
Human C3, the third component of human complement, contained mannose and N-acetylglucosamine as sugar components. The sugar chains were liberated from the polypeptide chains by hydrazinolysis, and the free amino groups were N-acetylated. The reducing end residues of the sugar chains thus obtained were tagged with 2-aminopyridine, and the pyridylamino (PA-) derivatives of sugar chains were separated by high-performance liquid chromatography. The structures of purified PA-sugar chains were analyzed by a combination of stepwise exoglycosidase digestions, size determination by paper electrophoresis, methylation analysis, Smith degradation, and partial acetolysis. These results showed that C3 contained two high-mannose type sugar chains ranging from Man5GlcNAc2 to Man9GlcNAc2. Analyses of the sugar chains of alpha- and beta-chains of C3 indicated that the alpha-chain contained mainly Man8GlcNAc2 and Man9GlcNAc2, while the beta-chain contained mainly Man5GlcNAc2 and Man6GlcNAc2.  相似文献   
157.
In attempting to clarify the roles of Dvl in the Wnt signaling pathway, we identified a novel protein which binds to the PDZ domain of Dvl and named it Idax (for inhibition of the Dvl and Axin complex). Idax and Axin competed with each other for the binding to Dvl. Immunocytochemical analyses showed that Idax was localized to the same place as Dvl in cells and that expression of Axin inhibited the colocalization of Dvl and Idax. Further, Wnt-induced accumulation of beta-catenin and activation of T-cell factor in mammalian cells were suppressed by expression of Idax. Expression of Idax in Xenopus embryos induced ventralization with a reduction in the expression of siamois, a Wnt-inducible gene. Idax inhibited Wnt- and Dvl- but not beta-catenin-induced axis duplication. It is known that Dvl is a positive regulator in the Wnt signaling pathway and that the PDZ domain is important for this activity. Therefore, these results suggest that Idax functions as a negative regulator of the Wnt signaling pathway by directly binding to the PDZ domain of Dvl.  相似文献   
158.
We have established a new HPLC method for derivatizing and quantifying glufosinate (GLUF) in human serum and urine using p-nitrobenzoyl chloride (PNBC). The p-nitrobenzoyl derivative of GLUF (PNB-GLUF) was produced quantitatively over 10 min at room temperature. PNB-GLUF possesses the property of ultraviolet (UV) light absorption with a lambda(max) of 272.8 nm, and was isolated from biological specimens by reversed-phase chromatography using Inertsil Ph-3. In experiments at a UV wavelength of 273 nm, GLUF has a quantitative detection limit of 0.005 microg/ml, and when it was added to both serum and urine to yield concentrations of 0.1-1000 microg/ml, its recovery rate was quite satisfactory: at least 93.8% in all cases. Further, the measured amounts of GLUF in 23 serum samples from patients intoxicated by ingestion of GLUF compared favorably with those obtained by fluorescence derivatization-HPLC using 9-fluorenylmethyl chloroformate (R=0.998). This technique of analysis is, in addition, applicable for Glyphosat, which possesses a chemical structure resembling that of GLUF, and it will be of great use in the determination of these two compounds.  相似文献   
159.
Summary By transferring a semidwarf gene (sd-1) from Taichung Native 1 into a tall Japanese cultivar, Norin 29, through seven backcrosses, a semidwarf near-isogenic line SC-TN1 was obtained. The proteins of the embryo in Norin 29 and SC-TN1 were separated by two-dimensional electrophoresis. Most of the proteins showed the same electrophoretic pattern. However, it was found that there was a difference in the appearance of two basic glycoproteins designated as SRP-1 and SRP-2. These proteins exhibited the same molecular mass, but different isoelectric points. Hybridization results indicated that a single locus controls SRP-1 and SRP-2 with codominant alleles. The gene symbol Srp was given to this locus, with alleles Srp-1 and Srp-2 responsible for SRP-1 and SRP-2, respectively. Srp-2 was found in all of the semidwarf cultivars and lines having sd-1, except a tall cultivar Tsaiyuan-chung. This finding suggests that Srp-2 may be closely linked with sd-1. The amounts of these proteins markedly increased after water absorption of the seed, suggesting that these proteins may be related to the early development of the plant.  相似文献   
160.
Relation between fatty acid composition of cellular phospholipids and the excretion of L-glutamic acid was investigated using Corynebacterium alkanolyticum GL–21 (a glycerol auxotroph).

When grown on n-hexadecane, the proportion of unsaturated fatty acids was higher in L-glutamic acid-accumulating cells than in L-glutamic acid-nonaccumulating cells. When grown on fructose or acetic acid, the reverse relation was observed. Moreover, cells containing no oleic acid produced L-glutamic acid from n-pentadecane.

These results suggest that the membrane permeability to L-glutamic acid is not always controlled by the cellular content of unsaturated fatty acids.  相似文献   
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