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71.
72.

Background

Japan became the world's first country to cover Helicobacter pylori eradication for chronic gastritis under its National Health Insurance (NHI) system in February 2013. Thereafter, H. pylori eradication dramatically increased and gastric cancer deaths began to decrease in Japan. However, the details of gastric cancer deaths and its prevention in the very elderly have not been fully elucidated.

Methods

We analyzed the temporal trend of gastric cancer deaths referencing data from Ministry of Health, Labour and Welfare reports and “Cancer Statistics in Japan–2021” and assessed the numbers of H. pylori test and gastric cancer screening using a national database and a report of cancer screening in Shimane Prefecture, respectively.

Results

Although gastric cancer deaths in total population have clearly decreased since 2013, those in people aged 80 years and older are still increasing. People aged 80 years and older represent 9% of the total population and accounted for half of all gastric cancer deaths in 2020. The numbers of H. pylori eradication and gastric cancer screening in people aged 80 years and older were 25% and 25% of those in other generations, respectively.

Conclusion

In spite of a dramatic increase in H. pylori eradication and a clear decrease in gastric cancer deaths in Japan, gastric cancer deaths in people aged 80 years and older are increasing. This might be due to fewer H. pylori eradication in the elderly than in other generations, indicating the difficulty of gastric cancer prevention in the very elderly.  相似文献   
73.
Romano-Ward syndrome (RWS) is an autosomal dominant disorder characterized by prolongation of the electrocardiographic QT interval, with clinical manifestations that include recurrent syncope and sudden death from ventricular arrhythmias. Presymptomatic diagnosis is difficult because of the variability in these signs among carriers, but it is important for clinical management to prevent sudden cardiac death. To find an LQT (long QT) locus in Japanese patients and to identify DNA markers useful for presymptomatic diagnosis, linkage analyses were undertaken in 13 Japanese families with RWS patients by means of two DNA markers located on 11p15.5. One of these marker loci, HRAS, was previously reported to be tightly linked to the LQT locus in another ethnic group. Our analyses of homogeneity suggest evidence for genetic heterogeneity of RWS within the Japanese population.  相似文献   
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Salicylic acid decarboxylase (Sdc) can produce salicylic acid from phenol; it was found in the yeast Trichosporon moniliiforme WU-0401 and was for the first time enzymatically characterized, with the sdc gene heterologously expressed. Sdc catalyzed both reactions: decarboxylation of salicylic acid to phenol and the carboxylation of phenol to form salicylic acid without any byproducts. Both reactions were detected without the addition of any cofactors and occurred even in the presence of oxygen, suggesting that this Sdc is reversible, nonoxidative, and oxygen insensitive. Therefore, it is readily applicable in the selective production of salicylic acid from phenol, the enzymatic Kolbe-Schmitt reaction. The deduced amino acid sequence of the gene, sdc, encoding Sdc comprises 350 amino acid residues corresponding to a 40-kDa protein. The recombinant Escherichia coli BL21(DE3) expressing sdc converted phenol to salicylic acid with a 27% (mol/mol) yield at 30 °C for 9 h.  相似文献   
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Mirror hands and feet (MIM, 135750) is a rare congenital anomaly, and mirror-image polydactyly is considered to be a variant of mirror hands and feet. To our knowledge, seven patients with the disorder have been reported in the literature. Parent-to-child transmission was reported in two families, which may indicate a single-gene defect inherited in an autosomal dominant fashion. We had previously encountered a boy with mirror-image polydactyly whose karyotype showed 46,XY,t(2;14) (p23.3;q13) de novo. We hypothesized that at least one of the putative genes responsible for the determination of an anterior-posterior limb pattern is disrupted by a translocation breakpoint. In this study, we identified a yeast artificial chromosome clone spanning a translocation breakpoint at 14q13, and the breakpoint was confirmed to be located between two loci, AFM200ZH4 and D14S306, within a genetic distance of 0.6 cM. Received: 25 September 1996 / Revised: 6 December 1996  相似文献   
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Chlorarachniophytes are flagellated and/or reticulopod-forming marine algae with chlorophyll a- and b-containing plastids of secondary endosymbiotic origin. They are one of only two algal groups known to possess a "nucleomorph" (i.e. the remnant nucleus of the eukaryotic endosymbiont that donated the plastid). Apart from the recently sequenced nucleomorph genome of Bigelowiella natans, little is known about the size, structure, and composition of chlorarachniophyte nucleomorph genomes. Toward the goal of better understanding nucleomorph genome diversity, as well as establishing a phylogenetic framework with which to interpret variation in chlorarachniophyte morphology, ultrastructure, and life cycle, we are studying a wide range of chlorarachniophyte strains from public culture collections and natural habitats. We have obtained 22 new chlorarachniophyte nuclear and nucleomorph 18S rRNA gene (18S rDNA) sequences and nucleomorph genome size estimates for 14 different strains. Consistent with previous studies, all of the chlorarachniophytes examined appear to possess three nucleomorph chromosomes. However, our results suggest considerable variation in nucleomorph genome size and structure, with individual chromosome sizes ranging from approximately 90 to approximately 210 kbp, and total genome sizes between approximately 330 kbp in Lotharella amoebiformis and approximately 610 kbp in unidentified chlorarachniophyte strain CCMP622. The significance of these phylogenetic and nucleomorph karyotype data is discussed.  相似文献   
80.
Omnivores are generally opportunistic foragers and have a flexible dietary response to resource abundance and availability. Their populations may consist of individuals that differ from each other in terms of their trophic positions, which implies that the dietary response to resource fluctuations differs within a population. We investigated how changes in the abundance of sika deer (Cervus nippon) affected dietary variation and body condition in the Asian black bear (Ursus thibetanus). We used fecal analysis, nitrogen stable isotopes (δ15N), and body measurements to determine whether the variation in dietary meat content of Asian black bears is positively related to variations in the density of the sika deer population, whether male bears have a higher trophic position compared to females, and whether dietary meat content is positively related with body mass or body condition of bears. We found a positive correlation between the occurrence of deer remains in bear feces and deer density, suggesting that bears change their diet in response to temporal changes in deer density. Male bears had higher δ15N values than females, and neither values varied when deer density decreased. Males selectively consumed deer after a reduction in deer density, whereas females consistently consumed more plant-based diet. The δ15N values were positively related with body mass of adult (>4 yr) bears but had no relationship with body condition of bears of either sex or any age class. Deer seem to be an important food source for large adult males, which have an advantage in mating. Thus, increasing herbivore abundance and availability altered the foraging strategy of Asian black bears, but the importance of herbivore on bear diet differs within a population.  相似文献   
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