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171.
K Kubo Y Yamazaki T Masubuchi A Takamizawa H Yamamoto T Koizumi K Fujimoto Y Matsuzawa T Honda M Hasegawa S Sone 《Canadian Metallurgical Quarterly》1998,158(3):979-984
To clarify the structure and function of the airways in Mycobacterium avium-intracellulare (MAI) infection, we performed pulmonary function tests and high-resolution computed tomography (HRCT) of the thorax in female patients 61 +/- 9 yr of age (n = 12) with pulmonary MAI infection without predisposing lung disease and compared their data with those of normal female volunteers 54 +/- 8 yr of age (n = 9). We calculated the E/I ratio, i.e., the average ratio of HRCT number at full expiration to that at full inspiration, as an index for the evaluation of air trapping distal to the small airways. Patients showed significant increases in residual volume and slope of phase III (DeltaN2) of the single-breath nitrogen test, and significant decreases in flow at 50 and 25% of FVC, suggesting hyperinflation and obstruction of the small airways. HRCT of patients revealed the small nodules and ectasis of bronchioles and small bronchi located mainly in segments (S) S2, S3, S4, and S5. The E/I ratio was significantly elevated in patients, and especially higher in the upper lung field than in the lower lung field, suggesting air trapping distal to the small airways. The difference of E/I ratio between the upper and lower field is probably related to the segmental distribution of CT abnormalities. These findings suggest that MAI infection can lead to air trapping distal to the small airways. 相似文献
172.
H Horino T Mimura K Kagechika M Ohta H Kubo M Kitagawa 《Canadian Metallurgical Quarterly》1998,46(4):602-609
A series of 3,4-dihydro-3-hydroxy-4-[(5-oxo-3,4-diazabicyclo[4.1.0]hept- 2-en-2-yl)oxy]-2H-1-benzopyrans and their analogues were synthesized and evaluated on potassium channel opening and hypotensive activities. Compound (-)-13B with a (4-methyl-5-oxo-3,4-diazabicyclo[4.1.0]hept-2-en-2-yl)oxy group for the 4-position of the benzopyran ring was 3 times as potent as EMD 57283 (II), the lead compound, in hypotensive activity. The results would demonstrate that 5-oxo-3,4-diazabicyclo[4.1.0]hept-2-en-2-yloxy moieties are effective as the substituents at the 4-position of benzopyran-type potassium channel openers. 相似文献
173.
T Shuto K Hirohashi S Kubo T Tsukamoto T Yamamoto K Wakasa H Kinoshita 《Canadian Metallurgical Quarterly》1998,45(23):1722-1725
BACKGROUND/AIMS: The purpose of this study was to clarify the clinicopathologic differences of hepatocellular carcinoma associated with the hepatitis B versus the hepatitis C virus. METHODOLOGY: One hundred and sixty-eight patients with resected hepatocellular carcinoma were tested for viral hepatitis. Ten (6%) had both the hepatitis B surface antigen and antibodies to the hepatitis C virus. Thirty-three (20%) had neither marker. Sixteen (9%) had only the hepatitis B surface antigen (group B), and 109 (65%) had only antibodies to the hepatitis C virus (group C). We compared groups B and C clinicopathologically. RESULTS: The mean tumor diameter was larger in group B than in group C (6.3 cm vs 3.4 cm), while group B patients were younger than group C (48 yrs vs 62 yrs, p<0.0001). Poor liver function, histologic cirrhosis and chronic active hepatitis were frequently found in group C. The 1- and 2-year tumor-free survival rates following surgery in group B were 67% and 33%, and those in group C were 73% and 49%. The 1-, 2-, and 3-year survival rates following surgery in group B were 78%, 68%, and 0%, while those in group C were 92%, 83%, and 76% (p=0.0189). CONCLUSIONS: Hepatocellular carcinoma with concomitant hepatitis B viral infection was found to present as larger tumors in younger patients with less severe liver dysfunction. Hepatocellular carcinoma with concomitant hepatitis C viral infection was often detected in follow-up studies when it was small. 相似文献
174.
175.
176.
The diversity of human immunodeficiency virus (HIV) in vivo has been reported. In this article, we propose a cellular automata
(CA) model describing the interactions between the immune system and HIV, and examine the effect of the diversity of these
interactions. The novel aspects of our CA model are that it not only considers four states (HIV, virgin, dead, infect) but
also the diversity exhibited by both HIV and T cells. We simulated maximum diversities for these states by simulating CA on
a computer. The model revealed that increased diversity had the effect of increasing the HIV population and simulation steps.
In addition, we observed that the CA model accurately reflects the occurrence of infection, incubation period, and the development
of AIDS. The CA model demonstrated that the diversity of the virus is the major factor affecting the success rate of the escape
of HIV from the immune response.
This work was presented in part at the 10th International Symposium on Artificial Life and Robotics, Oita, Japan, February
4–6, 2005 相似文献
177.
Tomohiro Kubo 《Electrical Engineering in Japan》2005,150(2):28-34
It is well known that the linear quadratic regulators of finite dimensional linear systems have the insensitivity property. In this paper, as a particular class of infinite dimensional systems, a neutral delay‐differential system is considered as a plant. A class of linear quadratic regulators is constructed for the plant using a simple feedback law, which does not require real‐time either integral or derivative operations. The feedback gain is calculated by solving a finite dimensional linear matrix inequality. First, it is shown that the regulator satisfies the circle condition. Then, its sensitivity against the parameter variations is evaluated. In the single‐input case, it is done by calculating the absolute value of the sensitivity function. In the multi‐input case, it is done by the so‐called “comparison sensitivity” method where the sensitivities of the closed‐loop system and the open‐loop system are compared based on certain sensitivity indices. Procedures used for the investigation of the regulator's properties are based on natural extension of methods proposed by Perkins and Cruz for the finite dimensional case. As a result, it is found that the class of linear quadratic regulators of neutral systems, similarly to finite dimensional systems, has the insensitivity property. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(2): 28–34, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20013 相似文献
178.
N Nakahata M Kutsuwa R Kyo M Kubo K Hayashi Y Ohizumi 《Canadian Metallurgical Quarterly》1998,26(3-4):311-323
Inhibitory mechanism of the water extract of Scutellariae Radix on prostaglandin E2 (PGE2) release was examined in C6 rat glioma cells. Scutellariae Radix reduced a Ca2+ ionophore A23187-induced PGE2 release by inhibition of arachidonic acid (AA) liberation. Sho-saiko-to and San'o-shashin-to, which contain Scutellariae Radix, also inhibited PGE2 release. A23187 caused phosphorylation of mitrogen-activated protein kinase (MAPK), resulting in activation of cytosolic phospholipase A2 (cPLA2). Scutellariae Radix and baicalein inhibited the phosphorylation of MAPK. Baicalein, but not baicalin, inhibited A23187-induced PGE2 release. These results suggest that baicalein in Scutellariae Radix reduces AA liberation through the inhibition of the MAPK-cPLA2 pathway. 相似文献
179.
For use as electrical and electronics parts, or automobile and mechanical parts, toughened poly(phenylene sulfide) (PPS) is desired. For these applications, our investigation centered on improving the toughness of PPS and developing elastomer-toughened PPS and elastomer-toughened compounds of PPS. Using chemically treated PPS and an olefinic elastomer with a functional group, we developed elastomer-toughened PPS using a reactive processing method. In the PPS matrix, the elastomer is finely dispersed. While the notched Izod impact strength of the original PPS is about 1 kg · cm/cm. clastomer-toughened PPS has a notched impact strength around 50 kg · cm/cm. The notched fracture surface of elastomer-toughened PPS is observed using a scanning electron microscope. We concluded that the mechanism for the toughening is attributed to energy dissipation by matrix yield. 相似文献
180.
Yukio Yasukawa 《亚洲传热研究》2006,35(2):165-177
An experimental study was performed on the nucleate boiling of water in the narrow space formed between an interference piece and the heating surface of heat‐proof glass. A past study analyzed the bubble growth due to the conduction of heat through the thinner liquid layer under a growing bubble; however, the thickness of the liquid layer was not shown experimentally. This study investigates the thickness of this thinner layer by the interference method. Almost no change was found on the thickness of the liquid layer under both the interference‐piece and on the heating surface. The experimental results indicate the great contribution of superheating of the test liquid to bubble growth. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(2): 165–177, 2006; Published online in Wiley InterScience ( www.interscience. wiley.com ). DOI 10.1002/htj.20100 相似文献