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81.
N Shinohara H Tanaka T Saito J Deguchi K Soda T Sugiyama Y Ishimaru S Sonoda 《Japanese journal of medical science & biology》1983,36(3):191-197
Eighty-two cases of typhoid fever were found in Matsuyama city in the period from 1974 to 1981. Seventy-six cases were found to be infected with Salmonella typhi other three with Salmonella paratyphi A, and the remaining three were diagnosed only clinically. The strains of S. typhi isolated from these patients showed such a variety of Vi-phage types as D1, D2, E1, M1, 53 and degraded Vi-positive strain (DVS). The concurrent survey of the city sewage and river waters for typhoid bacilli was conducted with total 578 samples taken therefrom. S. typhi was isolated from 120 of those samples. The Vi-phage types of the isolates were closely related with those of the isolates from the patients. The periodical examinations of the city sewage and the draining river may serve as a useful means for the controlling typhoid fever epidemics. 相似文献
82.
It was demonstrated that thyrotropin-releasing hormone (TRH) elicited a paradoxical increase in basal GH levels in cancer patients. Out of 94 cancer patients, 50 were found to be GH responders and this phenomenon was more frequently recognized in female than in male cancer patients. In cancer patients under 59 years of age, the GH response to TRH was significantly greater in females than in males, although there was no sex difference in the GH response in patients above 60 years of age. In female cancer patients, the GH response to TRH was significantly greater in patients under 59 years of age than in patients above 60 years of age, while there was no age difference in the GH response in male cancer patients. It was concluded that paradoxical responses of serum GH to TRH were recognized in 53 per cent of cancer patients and were more frequently observed in female than in male cancer patients. 相似文献
83.
N Yokoyama Y Murota T Negishi M Saito S Furuyama 《Canadian journal of physiology and pharmacology》1983,61(2):109-114
Cyclic GMP phosphodiesterase was investigated in the submandibular gland of the adult rat to elucidate the regulatory mechanisms of cGMP concentration in this gland. Ca2+ sensitivity was easily demonstrated as in other tissues using EGTA in the buffer for elution from DEAE-cellulose. The presence of inhibitor proteins for basal and calmodulin-activated portions of Ca2+-dependent phosphodiesterase was suggested. The inhibitor for the basal activity of Ca2+-dependent phosphodiesterase was deemed to be a heat-labile protein, which decreased Vmax, but had no effect on the Km value for cGMP. The presence of more than one kind of inhibitor for the calmodulin-activated portion of the Ca2+-dependent phosphodiesterase was also suggested. One of these, which was not absorbed on DEAE-cellulose, was a heat-labile protein which caused an increase of Km for cGMP, but no change of Vmax. 相似文献
84.
Stimulation of eicosapentaenoic acid metabolism in washed human platelets by 12-hydroperoxyeicosatetraenoic acid 总被引:2,自引:0,他引:2
Washed human platelets were not able to convert eicosapentaenoic acid (EPA) to thromboxane B3 (TXB3) and 12-hydroxyeicosapentaenoic acid (AA) to washed human platelets induced conversion of EPA to TXB3 and 12-HEPE. Esculetin, a specific inhibitor of 12-lipoxygenase, prevented the effect of AA, but cyclooxygenase inhibitor did not. The conversion of AA to TXB2 was not affected by the same dose of esculetin. These data suggest that products of AA formed by 12-lipoxygenase in human platelets have stimulatory effects on EPA metabolism. When AA was preincubated with washed human platelets, its effect on EPA conversion was reduced, suggesting that a labile product of AA formed by 12-lipoxygenase is involved in the facilitation of EPA metabolism. Addition of 12-hydroperoxyeicosatetraenoic acid directly to washed human platelets caused dose-dependent synthesis of TXB3 and 12-HEPE, while addition of 12-hydroxyeicosatetraenoic acid had no effect. Thus, 12-hydroperoxyeicosatetraenoic acid formed from AA promotes the metabolism of EPA in washed human platelets. 相似文献
85.
Throughout gestation pregnant mice received drinking water which contained [methyl-3H]thymidine (18.5 kBq/ml). The newborn mice were divided into two groups. One group was nursed by their own mothers, which were further supplied with tritiated thymidine until 4 weeks after delivery (Experiment I). The other group was nursed by "nonradioactive mothers" which were given no tritiated thymidine (Experiment II). Tritium incorporation into the small molecular components of the acid-soluble fraction, lipid, RNA, DNA, and protein was analyzed for the newborn mice at various ages. In Experiment II, total radioactivity per gram tissue decreased initially after birth with a half life of 2.5-2.9 days in spleen, liver, intestine, stomach, thymus, lung, kidney, heart, and brain. At about 2 weeks after birth, a slower component of tritium elimination due mainly to the DNA-bound tritium appeared. Specific activity of DNA at birth was organ specific, highest in heart and lowest in thymus. Cumulative absorbed dose in various organs was estimated for the first 4 weeks after birth based upon an assumption that total and DNA-bound tritium are uniformly distributed. The result showed that organ specificity of dose accumulation is obvious for DNA-bound tritium, highest in spleen (1.15 mGy) and lowest in brain (0.13 mGy). It was also shown that the tritium supply from mother's milk is of minor importance for dose accumulation of DNA-bound tritium in the cell nuclei of organs of suckling mice. 相似文献
86.
Sakurai Naoki; Inouhe Masahiro; Masuda Yoshio; Kuraishi Susumu 《Plant & cell physiology》1983,24(3):317-325
Sugar compositions of cell walls of dark-grown coleoptiles from12 barley strains, 11 of which were coleoptilar semi-dwarf strains,were analyzed on days 2 and 3 after germination. Major wallcomponents of the 12 strains were arabinose, xylose, and glucosein hemicellulose and cellulose; minor components were galactoseand mannose. The sugar content of each wall component per unit length wasnot correlated to any growth parameters calculated from a logisticequation simulating coleoptile growth, but the relative contentsof galactose and mannose in relation to the total wall sugarcontent was correlated to the growth rate on day 3 and the growthcontinuing period. These facts suggest that growth of these12 barley strains in the late growth stage is regulated by theminor wall components, galactose and mannose.
1 Dedicated to the late Professor Joji Ashida. (Received October 12, 1982; Accepted January 12, 1983) 相似文献
87.
The effects of photoperiod on the sex expression of cucumberflowers were examined in relation to the endogenous GA and ethyleneproduction with short day (SD)- and long day (LD)-sensitivecultivars under controlled environmental conditions. Growth of plants was greatly reduced under LD in both typesof cultivars. Reflecting this, GA activity was greater and ethyleneevolution less in plants grown under SD than in those underLD. However, the number of pistillate flowers increased underSD and LD in SD- and LD-sensitive cultivar, respectively, indicatingthat a change in sex expression did not coincide with hormonalchanges in the SD-sensitive cultivar. Thus, the effect of photoperiodon the sex expression was found to be separate, at least inpart, from the effect of GA or ethylene in cucumber. (Received September 16, 1982; Accepted December 7, 1982) 相似文献
88.
89.
90.
Two kinds of epithelial cells, dark and light types, are alternately arranged in the gill of Daphnia magna. The dark cell has numerous mitochondria and an elaborate tubular system containing two kinds of cytoplasmic tubules, small about 70 nm in diameter, and large about 130 nm in diameter. The former occur in bundles and seem to be smooth-surfaced endoplasmic reticulum. The latter, lined with a ridged surface coat and frequently open at the lateral and basal cell membrane, are regarded as extensions of the cell membrane. The atypical cell membrane of the dark cell is modified by repeated subunits of a cytoplasmic coat on the inner leaflet of the unit membrane. The light cell exhibits a high degree of basal infoldings of the cell membrane, which represent a magnification of the surface area of the cell. Large mitochondria between the infoldings often come into intimate association with the infolded cell membrane to form a regular array of parallel mitochondria interposed with the double cell membranes. The results suggest that at least the dark epithelial cells play an important role in the osmoregulation of this animal. 相似文献