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91.
The aim of the present study was to examine changes in the control of heat-dissipation responses to exercise associated with the diurnal variation in core temperature from the viewpoint of the regional response patterns. We studied seven men during exercise on a cycle ergometer at 100 W for 40 min at 25 degrees C at 0630 (morning) 1630 (evening) hours on 2 separate days. Oesophageal temperature (T(oes)), local skin temperature, local sweating rate (msw) on the forehead, back, forearm and thigh, and skin blood flow by laser Doppler flowmeter (LDF) on the back and forearm were measured continuously. The T(oes) at rest was significantly higher in the evening than in the morning, the difference averaging approximately 0.4 degrees C (P < 0.05). The T(oes) thresholds for each site in msw and that for back in LDF were significantly different between the two times of day (P < 0.05). The change in T(oes) thresholds for sweating and vasodilatation for morning and evening were similar to T(oes) at rest. Although msw on the forehead was significantly higher in the morning than in the evening, msw on the back was significantly higher in the evening than in the morning (P < 0.05). Total local sweating rate (msw,tot) for each site during exercise was significantly higher on the forehead than on the forearm in the morning, and on the back than on the forearm in the evening, respectively (P < 0.05). The results would suggest that the diurnal variation of heat-dissipation responses to exercise is influenced not only by a central controlling mechanism but also by changes in the regional differences.  相似文献   
92.
Cycads, the most primitive of the living gymnosperms, have been used and continue to be used for food and medicinal purposes by many cultures, although toxins must be removed before ingestion. In our quest to identify tropical plants that contain inhibitors of the cytochrome P-450 aromatase and thus may be efficacious in treating estrogen-dependent tumors, we have screened extracts from 5 species of cycad folia encompassing 3 genera: Cycas cairnsiana F. Muell., Cycas revoluta Thunb., Cycas rumphii Miq., Dioon spinulosum Dyer and Encephalartos ferox Bertol. All extracts were found to contain inhibitors of the human enzyme.  相似文献   
93.
The bcl-2 protooncogene was initially discovered at the t(14;18) chromosomal breakpoint in follicular lymphomas. It has been demonstrated that bcl-2 protein (Bcl-2) expression blocks apoptosis and plays an important role in cell development and maturation. In the present study, Bcl-2 expression was immunohistochemically examined in 103 cases of gastric carcinoma, as well as 64 cases of non-carcinous gastric mucosa, and its correlation with apoptosis, cell proliferation and p53 immunoreactivity was investigated. Bcl-2 was detected in 18.0% of differentiated-type gastric carcinomas (9 of 50) and 7.5% of the undifferentiated type (4 of 53). In adjacent intestinal metaplastic gastric epithelium, the incidence of Bcl-2 positivity in the incomplete type (21/23, 91.3%) was significantly higher than in the complete type (23/41, 56.1%) (P < 0.04). Double immunostaining for Bcl-2 and Ki-67 clearly revealed the majority of Bcl-2-positive cancer cells to be in a nonproliferating state, although some cancer cells expressed both proteins together. Statistical assessment demonstrated that the average Ki-67 labeling index and apoptotic labeling index in Bcl-2-positive foci were significantly lower than in Bcl-2-negative foci (P < 0.0001, P < 0.0003). In addition, a significant dissociation between Bcl-2 and p53 immunoreactivity was found in cancer tissues. These results indicate that aberrant Bcl-2 expression in gastric carcinomas possibly originates from intestinal metaplastic epithelium, and suggest a possible role in tumor development and growth.  相似文献   
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Casein hydrolysate, produced by an extracellular proteinase from Lactobacillus helveticus CP790, was fractionated by two-step reverse-phase HPLC. Only one fraction showed antihypertensive activity as measured by systolic blood pressure in spontaneously hypertensive rats after oral administration. Ten peptides in the fraction were further purified and identified by analysis of amino acid sequences. Each identified peptide was chemically synthesized, and the antihypertensive activity of each peptide was evaluated in spontaneously hypertensive rats. The synthetic peptide with a sequence of Lys-Val-Leu-Pro-Val-Pro-Gln, found in beta-casein, indicated strong antihypertensive activity from 2 to 10 h after oral administration of 2 mg of peptide/kg of BW, and the effect was maximal at 6 h after oral administration (-31.5 +/- 5.6 mm Hg). Moreover, the antihypertensive effect of the peptide was dependent on the dosage of peptide from 0.5 to 2 mg of peptide/kg of BW. Interestingly, the antihypertensive peptide showed lower inhibitory activity of angiotensin I-converting enzyme, but the activity was increased after pancreatin digestion.  相似文献   
97.
The Raman scattering experiments were carried out in Zn-doped and Zn-free Bi2Sr2CaCu2O8+y with optimal hole concentration below and above T c . The energy of pair-breaking peak in the B 1g Raman spectrum, corresponding to the magnitude of superconducting gap 2Δ 0, is suppressed by 1% Zn-doping. In the normal state, the B 1g Raman spectrum for Zn-doped sample shows no pseudogap behaviour, suggesting that the pseudogap is strongly smeared by Zn-doping.  相似文献   
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The effect of water concentration on the foaming tendency of lubricating oil containing the detergent additives Ca-phenate and amide was investigated from a surface chemical standpoint. Foam volume, dynamic surface tension and surface viscosity were measured at various water concentrations. It was proved that the increase of surface viscosity with water content was the main factor affecting foaming in the case of Ca-phenate but, in contrast, the Marangoni effect played an essential role in the case of amide.  相似文献   
100.
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