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1.
Summary We investigated possible association of and linkage between HLA and familial polyposis coli (FPC). In 182 individuals from 66 pedigrees of FPC and 108 individuals from a normal population, HLA-A,-B, and-C antigens were determined. When the frequencies of HLA antigens in 66 unrelated patients and in normal controls were compared, no association of FPC with HLA was observed. For the linkage analysis, HLA haplotypes of 17 affected sib pairs were investigated by the affected sib pair method. The number of pairs which shared two, one, and no haplotypes identical by descent was not significantly different from the number expected with random occurrence (P>0.95). Finally, seven families were analyzed using Morton's sequential test. A maximum lod score of-0.056 at a recombination fraction of 0.4, and a lod of-3.089 at a recombination fraction of 0.05 were obtained. Therefore, there is neither an association of nor linkage between FPC and HLA.  相似文献   
2.
Z-Val-, Z-Pro-, Z-Leu-Leu-, and Z-Leu-Pro-lysinals and BZ-DL-lysinal were chemically synthesized and tested as novel inhibitors for Achromobacter protease I (API), a lysine-specific serine protease. Among the lysinal derivatives tested, Z-Val-lysinal was the most potent competitive inhibitor, its Ki being estimated as 6.5 nM in an esterolytic assay with Tos-Lys-OMe. In an amidolytic assay, Z-Leu-Leu-lysinal was the most potent inhibitor and the apparent mode of inhibition was non-competitive. The Kis of the other lysinal derivatives in both esterolytic and amidolytic assays were more than 10(3) times lower than that of leupeptin. Z-Val-lysinol, lacking the aldehyde group, was a poor competitive inhibitor. These results suggest that acyl-, acylaminoacyl-, and acylpeptidyllysinals function as a transition-state inhibitor for Achromobacter protease I.  相似文献   
3.
The isolation of Chlamydia pneumoniae, especially from elderly persons, is generally not easy. Recently, we succeeded in isolating a chlamydial strain, which was designated KKpn-15, from a 57-year-old man suffering from acute bronchitis. It was compared with well established strains of C. pneumoniae, C. trachomatis and C. psittaci, and its biological properties, such as the morphology of elementary bodies (EBs) and inclusions, and the immunochemistry of EB proteins, were investigated. Based on the results obtained in the present study, it was confirmed that the new chlamydial strain, KKpn-15, is a member of the C. pneumoniae strain and that the organisms of KKpn-15 are useful as an antigen for the serodiagnosis and epidemiology of C. pneumoniae infection.  相似文献   
4.
Journal of Plant Research - A group of temperate grassland plant species termed the “Mansen elements” occurs in Japan and is widely distributed in the grasslands of continental East...  相似文献   
5.
The genusPittosporum includes about 160 species. Four species ofPittosporum occur in the Bonin Islands, and all of these are endemic to the islands. Electrophoretic studies of the four endemic species,P. tobira, from the Japanese mainland, andP. lutchuense var.denudatum from the Ryukyu Islands, were used to determine the origin and speciation pattern of the endemic species. 259 individuals were sampled from ten populations. Twenty loci in nine enzyme systems were resolved and used to calculate the gene frequencies for each population. A low genetic diversity was observed in three of the Bonin Island species, as is reported for other oceanic island plants. The exception,P. boninense, has the largest population size and widest distribution. A dendrogram generated by the UPGMA method shows two clusters. One consists of only the Bonin endemics, suggesting a monophyletic origin for these species.  相似文献   
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7.
The inactivation of papain brought about by low concentration of urea or guanidine hydrochloride was found to be a non-competitive type and that of cyanate ion to be a mixed type. The results are presented as Lineweaver-Burk plots.

These inactivations are not due to a change in the secondary structure of papain molecule as a result of the measurements of optical rotatory dispersion, circular dichroism, and UV-difference spectra.  相似文献   
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A novel series of pyrrolidine derivatives as Na+ channel blockers was synthesized and evaluated for their inhibitory effects on neuronal Na+ channels. Structure–activity relationship (SAR) studies of a pyrrolidine analogue 2 led to the discovery of 5e as a potent Na+ channel blocker with a low inhibitory action against human ether-a-go-go-related gene (hERG) channels. Compound 5e showed remarkably neuroprotective activity in a rat transient middle cerebral artery occlusion (MCAO) model, suggesting that 5e would act as a neuroprotectant for ischemic stroke.  相似文献   
10.
Maleate cis-trans isomerase in Alcaligenes faecalis IB–14 was induced by malonate and purified about 100-fold over the crude cell-free extract by treatments of ammonium sulfate fractionation, Sephadex G–100 gel filtration, DEAE-cellulose and DEAE-Sephadex A–50 column chromatography. The preparation was shown to be monodisperse on ultracentrifugal analysis and Svedberg value was found to be 3.84 S.

The enzyme was most active at pH value around 8.3 and was stable over the range of pH 5.0 to 7.0 in the presence of dithiothreitol (DTT) for a few weeks, but in the absence of it, the enzyme activity was markedly decreased, especially in the alkaline region. The enzyme activity was inhibited by various sulfhydryl reagents and oxidizing agents, whereas it was not affected by metal chelating agents. The inhibition by Hg2+ and PCMB was overcome by the addition of sulfhydryl compounds such as DTT, 2-mercaptoethanol, l-cysteine and glutathione. It was observed that the enzyme did not require co-factor for its function.

Kinetic studies showed that Michaelis constant for maleate was 2.8×10?3 m and the enzyme did not catalyze the reverse reaction.  相似文献   
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