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排序方式: 共有443条查询结果,搜索用时 531 毫秒
91.
92.
T Nagao M Nakashima FW Smart RA Bond KJ Morrison PM Vanhoutte 《Canadian Metallurgical Quarterly》1995,26(5):679-681
The membrane potential of vascular smooth muscle cells of the porcine coronary artery was measured to examine whether serotonin evokes endothelium-dependent hyperpolarization, and if it does, whether the electrical responses are modulated by the chronic dietary intake of NC 020, a defined fish oil. Serotonin induced transient, concentration-dependent hyperpolarizations of coronary arterial smooth muscle cells. The hyperpolarization was observed in tissues with, but not in those without endothelium. In coronary arteries obtained from pigs fed chronically with NC 020, serotonin induced significantly larger hyperpolarizations than those observed in control arteries. These results suggest that endothelium-dependent hyperpolarization may contribute to the endothelium-dependent relaxation evoked by serotonin and to its potentiation by the dietary intake of fish oil (NC 020). 相似文献
93.
OBJECTIVE: The aim of this study was to determine the effects of radiation on the secretion of saliva from mucous salivary glands in comparison with serous salivary glands. STUDY DESIGN: The minor salivary glands of the palate were used as an example of mucous glands, while the parotid glands were used as an example of a serous secretion organ. Serial flow rate measurements of the parotid and palatal glands were taken over a period of approximately 9 months in 13 patients who suffered from malignancies of the head and neck region. Twelve patients consented to take part in a second study in which salivary flow was stimulated by oral pilocarpine before and at the conclusion of radiotherapy and 7 months later. Complaints and symptoms were recorded at each time of measurement. RESULTS: After radiotherapy, the secretory performance of the parotid glands dropped off rapidly and irreversibly. Salivary secretion from the palatal glands was not totally diminished as a result of radiation. Clinical complaints and histologic findings indicate a serious alteration of the tissues irradiated; however, residual secretion from the remaining parenchyma of the mucous glands still remains. Pilocarpine produced a clinically significant increase of salivary flow from the palatal glands before and 7 months after radiation. Secretory performance of the parotid glands could not be sufficiently increased by stimulation with pilocarpine after radiotherapy. Clinical side effects and risks for the treatment of symptomatic postradiation xerostomia with pilocarpine were minimal. CONCLUSIONS: These findings emphasize the greater resistance and recoverability of the mucous secreting minor palatal glands in comparison with the serous secreting parotid glands. They also indicate the significant postradiation ability of the mucous secreting glands to be stimulated by pilocarpine. 相似文献
94.
This paper presents a novel technique using frequency modulation (FM) to improve the efficiency of an inductor commutation soft-switched pulse-width-modulation (PWM) inverter (ICSI). In the ICSI, a circulating current for soft switching always flows through the switches of the inverter, independent of the load and input signal. The circulating current significantly deteriorates the efficiency of ICSI. With the FM technique, the circulating current is effectively suppressed without sensing any current or voltage in the inverter. Efficiencies of ICSI and ICSI with FM (FM ICSI) are analyzed and verified experimentally. As a result, the efficiency of FM ICSI rises about 20%-40% compared with the ICSI 相似文献
95.
BACKGROUND: Cow dust is one of the most important inducers of occupational allergic diseases in Finland. For example, in 1991 it accounted for almost 40% of the new occupational asthma cases. OBJECTIVE: This study compares the performance of the purified major cow allergen (BDA20) and crude bovine epithelial extract (BEA) in diagnostic tests and examines the role of milk allergy-associated bovine proteins (bovine serum albumin, alpha-lactalbumin, beta-lactoglobulin, casein) in respiratory cow allergy. METHODS: The humoral responses of cow-asthmatic and healthy farmers to the various components of BEA were analysed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting. The levels of specific IgE and IgG antibodies were quantificated with enzyme-linked immunosorbent assays (ELISAs). The cellular responses were analysed with antigen-specific lymphocyte proliferation tests. RESULTS: The specific anti-BDA20 IgE measurement was found to be best in distinguishing between the asthmatic farmers and their healthy colleagues. It proved possible to determine a cut-off value that gave the analysis a specificity and sensitivity of 100%; the distinction between the two groups was highly significant (P < 0.0001). In the lymphocyte proliferation analysis, cow asthma was more closely associated with reactivity to BDA20 than to BEA. In the measurement of anti-BDA20 and anti-BEA IgG antibody levels, considerable overlap between the groups was observed, suggesting that these antibodies are not directly involved in cow allergy. When proteins associated with milk allergy were used as test reagents, no statistically significant differences could be observed between the groups, except for anti-casein IgE antibodies the level of which, however, overlapped considerably between the farmer groups. CONCLUSION: These findings suggest that purified BDA20 is better than BEA for diagnosing cow asthma and that proteins associated with milk allergy are of only marginal significance in this disease. 相似文献
96.
GRADE, a software environment for machine translation is described. It has been developed for the Mu machine translation project, which was supported by the Science & Technology Agency of the Japanese Government. GRADE consists of 3 components: (1) a grammar writing language based on flexible tree-to-tree transformation rules with a control mechanism and an interpreter; (2) software tools for constructing and maintaining grammar rules; and (3) software tools for developing dictionary databases which are based on the concept ofneutral dictionary. In this paper, these software packages are discussed from the viewpoint of the development of a large scale machine translation system.The authors thank their colleagues in the Mu project, who helped in the development of the system and already returned to their private companies to develop their own machine translation systems. We also wish to thank the researchers at the Japan Information Center of Science and Technology, and the Electrotechnical Laboratory of Kyoto University for their cooperation. 相似文献
97.
G Kawa S Nagao A Yamamoto K Omori Y Komatz H Takahashi Y Tashiro 《Canadian Metallurgical Quarterly》1994,4(12):2040-2049
Recently, it has been reported that Na,K-ATPase in the renal epithelia of human autosomal dominant polycystic kidney disease and cpk mouse, a murine model of autosomal recessive polycystic kidney disease, mislocates to apical plasma membrane and that mislocated Na,K-ATPase causes the cyst formation. Whether the DBA/2FG-pcy mice, which are presumably a suitable model for autosomal dominant polycystic kidney disease, also exhibit the reversal polarity of Na,K-ATPase localization was examined. Kidneys of newborn DBA/2FG-pcy mice, and those at early and late stages of cyst development were examined by immunohistochemical techniques. At any stage, abnormal distribution of Na,K-ATPase on the apical membranes of tubular epithelial cells could not be detected. It is suggested that cysts can be formed without reversed polarity of Na,K-ATPase distribution in pcy mice. 相似文献
98.
K Baba K Nagao M Matsuda R Nishimura Y Matsuoka Y Yamashita M Fukuda A Higuchi H Matsumoto A Murakami F Tanaka F Imamura 《Canadian Metallurgical Quarterly》1998,51(11):974-977
We experienced two cases of spontaneous hemopeumothorax. One case was a 17-year-old male with a complaint of back pain. A chest tube for rapid pleural evacuation disclosed hemorrhage as much as 3,000 ml, with drainage volume being gradually decreased. He needed about two month's admission because of complication of pyothorax. The other case was a 46-year-old male with a complaint of chest pain. Chest X-P gave the diagnosis of right hemopeumothorax. Thirty minutes later, he became shock, and five hours later, we performed an emergency intervention of video-assisted thoracoscopic surgery (VATS). Bleeding site of a funicular structure from the parietal pleura was stopped by clipping, with excellent postoperative results. Spontaneous hemopeumothorax is often indicated for early surgical intervention because of association with a high risk of hemorrhagic shock. In such a case, VATS is very helpful. 相似文献
99.
H Iwase Y Yamada S Ootani Y Sasaki M Nagao K Iwadate T Takatori 《Canadian Metallurgical Quarterly》1998,94(1-2):9-14
This paper describes risk factors for dental caries identified among 491 2-year-olds in the city of Ume?, Sweden. The study was performed as a risk screening for dental caries according to a method developed for use by dental assistants. The sugar consumption was high, 80% of the 2-year-olds had sweets once a week or more and 25% had sweet beverages once a day or more frequently. In addition, 14% of the children had a meal at night and most common were formula, bovine milk or breastmilk. The majority of the parents brushed the child's teeth at least daily using fluoride toothpaste. Among the children 6% had a chronic somatic disorder and 6% had an intolerance towards specific foods, milk being the most common. The high level of sugar consumption indicates that improved dental health education focusing on the importance of limiting sugar consumption is needed among parents with young children. 相似文献
100.
Raman and infrared active vibrons and phonons in the solid molecular hydrogen at megabar pressures have been studied by the first–principles band theoretical calculations assuming the hcp lattice of the centers of the molecules. The frequencies of the out–of–phase stretching motion of the two molecules in the unit cell are higher than those of the in–phase stretching motion. Pressure dependence of the frequency of a phonon–like mode, which lies in 1300 cm
–1 ~ 1900 cm
–1
at pressures 70 GPa ~ 200 GPa, is in good agreement with the recent experiments. Our results suggest that the lattice of the solid hydrogen remains hcp beyond the phase transition at 150 GPa. 相似文献