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101.
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
102.
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
103.
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
104.
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
105.
The triad is the junctional association of transverse tubule with sarcoplasmic reticulum terminal cisternae. A procedure for the isolation of highly enriched triads from skeletal muscle has been described in the previous paper. In the present study, the structural features of isolated triads have been examined by thin-section, negative-staining, and freeze-fracture electron microscopy. In isolated triads, key features of the structure observed in situ have been retained, including the osmiophilic "feet," junctional structures between the transverse tubule and terminal cisternae. New insight into triad structure is obtained by negative staining, which also enables visualization of feet at the junctional face of the terminal cisternae, whereas smaller surface particles, characteristic of calcium pump protein, are not visualized there. Therefore, the junctional face is different from the remainder of the sarcoplasmic reticulum membrane. Junctional feet as viewed by thin section or negative staining have similar periodicity and extend approximately 100 A from the surface of the membrane. Freeze-fracture of isolated triads reveals blocklike structures associated with the membrane of the terminal cisternae at the junctional face, interjunctional connections between the terminal cisternae and t-tubule, and intragap particles. The intragap particles can be observed to be closely associated with the t-tubule. The structure of isolated triads is susceptible to osmotic and salt perturbation, and examples are given regarding differential effects on transverse tubules and terminal cisternae. Conditions that adversely affect morphology must be considered in experimentation with triads as well as in their preparation and handling. 相似文献
106.
Expression of adenovirus type 12 early region 1 in KB cells transformed by recombinants containing the gene. 总被引:10,自引:4,他引:6
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K Shiroki I Saito K Maruyama Y Fukui Y Imatani K I Oda H Shimojo 《Journal of virology》1983,45(3):1074-1082
The adenovirus type 12 (Ad12) early region 1 (E1) gene was introduced into KB cells by using a dominant selection vector, pSV2-gpt, and over 80 Gpt+ KB cell clones were established. Three types of recombinant DNAs (gAE1A, gARC, and gABA) were constructed. They contained the AccI-H, EcoRI-C, and BamHI-A fragments, respectively, of Ad12 DNA in pSV2-gpt. Five of 50 (10%) gABA-transformed cell clones, 12 of 18 (67%) gAE1A-transformed cell clones, and 10 of 18 (56%) gARC-transformed cell clones complemented the growth of Ad5 dl312 (deletion in E1A) and were designated as Gpt+ Ad+ cell clones. In these cell clones at their early passages, recombinant genome sequences were detected in cellular DNA and were expressed. T antigen g (the E1A gene product) was detected by immunofluorescence. The Gpt+ Ad+ cell clones supported the growth of Ad5 deletion mutants in parallel with the expression of Ad12 E1A or E1A plus E1B genes. After infection of Gpt+ Ad+ cell clones with Ad5 dl312, the early genes of dl312 were efficiently transcribed, indicating the expression of the pre-early function of the Ad12 E1A gene. Two clones each from gAE1A-,gARC-, and gABA-transformed cells were subcultured for a long period to determine the stability of the transfecting DNAs. Subculture in a nonselective medium resulted in cells which lost the transfecting DNAs. Subculture in a selective medium resulted in the selection of cells which maintained the gpt gene expression but lost the Ad12 gene expression. These results indicate that the transfecting DNA is present in an unstable state in KB cells. 相似文献
107.
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
108.
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
109.
110.
Quantitative isolation of total glycosphingolipids from animal cells 总被引:49,自引:0,他引:49
The quantitative isolation of total glycosphingolipids from crude lipid extracts without contamination from other lipid classes is described. The method consists of (a) acetylation of total lipids with pyridine and acetic anhydride, (b) separation of acetylated glycolipids from nonglycolipids on a magnesia-silica gel (Florisil) column, and (c) deacetylation of glycolipid in chloroform-methanol-sodium methoxide. This method is useful for determination of microgram quantities of glycolipids derived from less than 1 ml of packed cells. 相似文献