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31.
32.
The copper and Iron status in the liver of non-tumor bearing Long-Evans Cinnamon (LEC) rats (average age 17 months) was investigated. A direct quantitation of loosely-bound copper and iron was also investigated by using a chelating agent, nitrilotriacetic acid (NTA-chelatable free copper and iron). Besides the total copper and iron contents, the level of NTA-chelatable free copper was also higher in LEC rats than In LEA rats (P<0.05). But for the free iron level there was no signiflcant difference between the two rat groups (P>0.05). The formation of thiobarbituric acid-reactive substances was higher In LEC rats than In LEA rats (P<0.01). The 4–hydroxy-2–nonenal (HNE)-modified proteins were also clearly demonstrated in LEC rat liver. The copper and iron which produced the most important effect In the process of oxidative damage in LEC rats could not be distinguished. Even though free copper, which could induce free radical injuries, was increased in LEC rats, neither tumor-induction nor preneo-plastic lesions in the experimental LEC rats were observed. Therefore it is speculated that the elevation of a free iron is another important factor. Copper and iron, both important translation metals In the body, may participate In the Induction of DNA damage and oncogenesls  相似文献   
33.
We measured the aerobic capacity, sweat rate and fluid intake of trained athletes during outdoor exercise and examined the relationship between aerobic capacity and thermoregulatory responses at high ambient temperatures. The maximal aerobic capacity ( ) of the subjects, nine male baseball players of college age, was determined by maximal exercise tests on a cycle ergometer. The subjects practised baseball regularly without drinking fluids from 1330 to 1530 hours. After 30 min rest, they played a baseball game with free access to a sports drink at 15°C from 1600 to 1830 hours. At a mean ambient temperature of 36.7 (SEM 0.2)°C, the mean percentage of body mass loss (m b) and increase of oral temperature (T o) from 1330 to 1530 hours was 3.47 (SEM 0.12)% and 0.81 (SEM 0.14)°C, respectively. The sweat loss from 1330 to 1830 hours was 56.53 (SEM 1.56)ml · kg–1 of body mass (M b) while the mean fluid consumption was 44.78 (SEM 2.39)ml · kg–1 ofm b, with recovery of 76.08 (SEM 2.81)% of sweat loss. The was significantly inversely correlated withm b, fluid intake and rehydration amount, but showed no correlation withT o. These results would suggest that at a given exercise intensity in subjects with a higher aerobic capacity body temperature is maintained with a lower sweating rate than that in subjects with a lower aerobic capacity.  相似文献   
34.
Environmental factors essential for the first stages of B lymphopoiesis remain elusive. Here, we report that immediately after commitment to B lineage, precursors become dependent on a chemokine SDF-1 and its receptor CXCR4 using mutant and radiation chimeric mice. In bone marrow, generation of the earliest identifiable B cell precursor populations requires CXCR4. In fetal liver, we identified Lin(-)CD19(-)c-kit(+)IL-7Ralpha(+)AA4.1(+), the earliest unipotent B cell precursor population, and found that its development was severely affected in SDF-1(-/-) embryos but not in IL-7(-/-) embryos. Lin(-) T cell progenitors appeared normal in SDF-1(-/-) embryos. Moreover, SDF-1 exhibited specific biologic activities on the earliest B cell precursors. SDF-1 provides the first example of a cytokine responsible for the earliest B lineage stages.  相似文献   
35.
We have previously reported 2 cases of healthy men showing in vivo monoclonal expansion of mature CD4? CD8? αβ T cells. In the present study, an additional 3 adults were found to exhibit such an expansion, among a total 464 adult donors studied. These 5 individuals were otherwise physiologically normal, with no history of severe illness and autoimmune disease at the time of examination. To investigate the mechanisms of the clonal expansion, further characterization of the clonal cells was attempted. No apparent preference for usage of the Tcell receptor β chain variable region was observed in the clonal T cells. These clonal T cells showed lectin-dependent or redirected antibody-dependent cell-mediated cytotoxicities, whereas they could not lyse autologous lymphoblastoid cell lines. Failure of Fas antigen expression was not observed for any of these clones. These results suggest that clonal expansion of CD4? CD8? αβ T cells frequently occurs in the periphery without any T cell abnormalities.  相似文献   
36.
37.
A very rare case of renal cell carcinoma of the horseshoe kidney that produced AFP and caused hypercalcemia is reported. The relationship between this renal cell carcinoma and hypercalcemia was obvious, but the mechanism of hypercalcemia was not revealed. The presence of AFP in cancer cells was demonstrated using the "ABC" method.  相似文献   
38.
The purpose of this study was to examine how gold kiwifruit pericarp (pericarp is defined as the skin of the fruit) consumption and the timing thereof affect the postprandial blood glucose profile. The study was conducted on twelve healthy volunteers (six men and six women). According to our results, the simultaneous intake of gold kiwifruit with bread and the prior intake of gold kiwifruit evidently suppressed the postprandial blood glucose elevation compared with exclusive bread intake. There was no significant difference in postprandial blood glucose changes between the ingestion of gold kiwifruit pericarp and pulp and that of gold kiwifruit pulp only. The highest postprandial blood glucose elevation was suppressed by 27.6% and the area under the blood glucose elevation curve by 29.3%, even with the exclusive ingestion of gold kiwifruit pulp. We predicted that the ingestion of both the pericarp and pulp of gold kiwifruit would reduce the postprandial blood glucose elevation to a greater extent than that of gold kiwifruit pulp only; however, there was no significant difference between the two. These results indicate that gold kiwifruit consumption significantly suppresses the postprandial blood glucose elevation regardless of pericarp presence or absence and the timing of ingestion.  相似文献   
39.
Paraganglionic tissues incidentally observed in the gallbladder are presented. The patients, a 51- and a 55-year-old woman, underwent gallbladder resection for chronic cholecystitis with gallstones. Two and one paraganglionic tissues were observed in the subserosal connective tissue of the two gallbladders, respectively. Immunohistochemically, the chief cells were positive for chromogranin A, and the sustentacular cells were positive for S100 protein. Tyrosine hydroxylase (in two of three), dopamine beta-hydroxylase (in one of three), methionine-enkephalin (in two of three), and leucine-enkephalin (in two of three) were also positive in a small amount of the chief cells. These structures, which slightly resembled adrenal medulla or retroperitoneal paraganglia, might be misunderstood as an infiltration of primary or metastatic carcinoma into the subserosal connective tissue.  相似文献   
40.
1. Rat proteinase-activated receptor-2 (PAR2) variants were stably expressed in rat KNRK cells: (a) wild-type (wt) - PAR2; (b) PAR2PRR, with the extracellular loop 2 (EL-2) sequence P231E232E233mutated to PRR and (c) PAR2NET, with the EL-2 sequence, PEEV changed to NETL. Cell lines were evaluated for their sensitivity (calcium signalling) towards trypsin and the receptor-activating peptides, SLIGRL-NH2, SLIGEL-NH2, trans-cinnamoyl(tc)-LIGRLO-NH2, and SFLLR-NH2. 2. SLIGEL-NH2 exhibited low potency (1 : 200 relative to SLIGRL-NH2) in wild-type PAR2. Its activity was increased 5 fold in PAR2PRR, but it was inactive in PAR2NET. 3. In PAR2PRR, the potencies of SLIGRL-NH2, tc-LIGRLO-NH2, and SFLLR-NH2 were decreased by 80 - 100 fold. But, the potency of trypsin was decreased by only 7 fold. 4. In PAR2NET, highly homologous in EL-2 with proteinase-activated receptor-1 (PAR1), the potency of the PAR1-derived peptide, SFLLR-NH2, was reduced by 100 fold compared with wt-PAR2, whereas the potency of the PAR2-derived AP, SLIGRL-NH2 was reduced 10 fold. In contrast, the potency of trypsin in PAR2NET was almost the same as in wt-PAR2. 5. We conclude that the acidic EL-2 tripeptide, PEE, in PAR2 plays an important role in governing agonist activity. 6. The data obtained with the PEEV-->NETL mutation suggested: (a) that SLIGRL-NH2 and SFLLR-NH2 interact in a distinct manner with PAR2 and (b) that SFLLR-NH2 may interact differently with PAR2 than it does with PAR1. 7 The differential reductions in the potencies of SLIGRL-NH2, compared with trypsin in the PAR2PRR and PAR2NET cell lines point to differences between the interactions of the trypsin-revealed tethered ligand and the free receptor-activating peptide with PAR2.  相似文献   
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