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481.
Human hypertension caused by mutations in WNK kinases   总被引:1,自引:0,他引:1  
Hypertension is a major public health problem of largely unknown cause. Here, we identify two genes causing pseudohypoaldosteronism type II, a Mendelian trait featuring hypertension, increased renal salt reabsorption, and impaired K+ and H+ excretion. Both genes encode members of the WNK family of serine-threonine kinases. Disease-causing mutations in WNK1 are large intronic deletions that increase WNK1 expression. The mutations in WNK4 are missense, which cluster in a short, highly conserved segment of the encoded protein. Both proteins localize to the distal nephron, a kidney segment involved in salt, K+, and pH homeostasis. WNK1 is cytoplasmic, whereas WNK4 localizes to tight junctions. The WNK kinases and their associated signaling pathway(s) may offer new targets for the development of antihypertensive drugs.  相似文献   
482.
We report that the organic salt (EDO-TTF)2PF6 with 3/4-filled-band (1/4-filled in terms of holes), which forms an organic metal with strong electron and lattice correlation, shows a highly sensitive response to photoexcitation. An ultrafast, photoinduced phase transition from the insulator phase to the metal phase can be induced with very weak excitation intensity at near room temperature. This response makes the material attractive for applications in switching devices with room-temperature operation. The observed photo-induced spectroscopic change shows that this photoinduced phase transition process is caused by the cooperative melting of charge ordering assisted by coherent phonon generation.  相似文献   
483.
To study the behavior of histamine-producing bacteria during the processing and storage of shimesaba, we inoculated histamine-producing bacteria into raw mackerel and then evaluated bacterial counts and histamine content at each shimesaba processing step. Six histamine-producing bacteria—Morganella morganii, Enterobacter aerogenes, Raoultella planticola, Photobacterium damselae (2 strains), and Photobacterium phosphoreum—were inoculated onto the surface of mackerel fillets at various cell densities (no inoculation, 104, and 10cfu ml?1). The fillets were then treated according to the common procedure used for processing shimesaba. The concentration of NaCl in brine during the salting procedure was 10 % (w/v), and the main ingredients of the marinade broth were 27 % vinegar, 3.8 % sucrose, 0.3 % sodium glutamate, and 0.1 % sodium succinate. The level of histamine-producing bacteria and of histamine did not increase during the salting and marinating procedures. However, during the storage tests, histamine content increased remarkably in the shimesaba products stored at 10 °C for 3 days, and organoleptical degradation was also observed. However, significant deterioration, based on bacterial count, histamine content, and organoleptic evaluation, was not observed in samples stored at 5 °C. These results indicate that the use of traditional marinade broth during the processing of shimesaba and storage below 5 °C are effective methods for preventing histamine accumulation.  相似文献   
484.
ABSTRACT:   Household surveys of small-scale fishing were conducted in Svay Ear and Srey Rangit villages in Kompong Thom Province, Cambodia. Data were collected from 104 of 183 households and 105 of 140 households in Svay Ear and Srey Rangit, respectively. In both villages, almost all households conducted rice cultivation and approximately 75% of them also conducted fishing. Three fishing groups: (i) inside lake; (ii) around lake; and (iii) around village were observed in both villages, according to their main fishing grounds. The inside lake group conduct fishing only in Tonle Sap Lake which is located 30 km away from the villages. The around lake group fish in lakes, marshes and flooded forests adjacent to Tonle Sap Lake, which are more than 5 km from the villages. The around village group collects fish from rice fields and ponds located inside the villages and also in some streams, rivers and lakes adjacent to the villages. The distance to the fishing grounds is less than 5 km from the villages. Most fishing groups were the inside and around lake groups, which occupied 76.0 and 65.7% of Svay Ear and Srey Rangit, respectively. These two groups produced 80.6 and 69.7% of the respective village annual total fish catches. These two groups sold a large portion of their fish catches. Although previous reports indicated that small-scale fishing is for subsistence, present results indicated that small-scale fishing was commercially conducted and fishing was important as an income source.  相似文献   
485.
To clarify the feeding habits of seagrass fishes, we examined the gut contents from 42 fish species collected in seagrass habitats in Trang. Thirteen species showed ontogenetic and/or seasonal changes in food-use patterns. Smaller individuals generally preyed on small planktonic items (e.g., copepod larvae) or small benthic/epiphytic crustaceans (e.g., harpacticoid copepods), with subsequent changes to other prey items (e.g., shrimps, crabs, detritus and filamentous algae) with growth. The most important dietary items for the seagrass fish assemblages comprised benthic/epiphytic crustaceans, detritus, and planktonic copepods. Cluster analysis based on dietary overlaps showed that the seagrass fishes comprised eight feeding guilds (large benthic/epiphytic crustacean, detritus, planktonic animal, small benthic/epiphytic crustacean, mollusc, invertebrate egg, polychaete, and fish feeders). Of these, the first three guilds were the most abundantly represented, whereas the last three were each represented by only a single species.  相似文献   
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