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991.
Genju Ooneda Yoji Yoshida Keiji Suzuki Takemi Sekiguchi 《Virchows Archiv : an international journal of pathology》1973,361(1):31-38
Summary The morphogenesis of the vascular lesions, which were considered to be the immediate cause of hypertensive intracerebral hemorrhage, was morphologically studied in autopsy cases. The direct cause of the hemorrhage was the rupture of the intracerebral microaneuysms resulted from the plasmatic arterionecrosis. The arterionecrosis was predominantly present in the intracerebral arteries of approximately 150 µ diameter, especially in the external branches of the arteriae corporis striati mediae in the putamen, and characterized by medial smooth muscle cell loss, blood plasma insudation in the intima, histolysis of the internal elastic lamina and intimal collagenous fibers, fibrin deposition (fibrinoid degeneration) in the intima, and luminal dilatation. The morphogenesis of the arterionecrosis was the development of histolysis as well as fibrinoid degeneration caused by blood plasma insudation in the wall of the intracerebral arteries with preceding necrosis and loss of medial smooth muscle cells and subsequent fibrous intimal thickening with dilated lumina. Intracerebral microaneurysms were also formed by the plasmatic arterionecrosis in a narrow sense, in which histolysis due to blood plasma insudation had occurred, but fibrin (fibrinoid substance) deposition in the intima had not yet arisen. 相似文献
992.
Short-termbioassays such as that of Ames and co-workers may be a practical method of monitoring industrial environments for the presence of biologically active and potentially hazardous materials. In general, these assays detect agents that cause damage to DNA which may lead to mutations, cancer, birth defects and to other diseases. Used to monitor industrial environments, such tests can indicate the presence of biologically active materials and can detect changes in the levels of these materials in the air. This paper reviews the types of bioassays which are presently available and considers their applicability to evaluation of occupational exposures in the coal conversion and oil shale industries. As no direct assessment of the degree of human health hazard can be made from the results of such tests, the choice of appropriate comparisons, such as ambient air, are discussed. The advantages and limitations of such systems are considered. Some research needs for the application of bioassays to industrial monitoring are also discussed. 相似文献
993.
994.
995.
Studies on the nature of the proximal bladder carcinogens 总被引:1,自引:0,他引:1
996.
997.
Purpose
In frequency doubling technology (FDT) perimetry, the incidence of tests classified as unreliable is higher in the second-tested left eye than in the first-tested right eye when perimetry is performed without a rest period. The purpose of this study was to determine whether the incidence of unreliable results was reduced when the retest began after a 5-min rest period.Methods
The subjects were 978 residents of Miyoshi City, Japan, who underwent FDT perimetry during a medical checkup. FDT perimetry was always performed first on the right eye and then on the left eye without a rest interval. When the results were determined to be unreliable, FDT perimetry was repeated after a 5-min rest interval.Results
The perimetric results were determined to be unreliable in one eye of 119 subjects; the results of the first-tested right eye were unreliable in 24 (20.2%), and the results of the second-tested left eye were unreliable in 95 (79.8%) subjects. This difference in the incidence of reliability was significant (P < 0.001). After a 5-min rest interval, the percentage of eyes with reliable results recovered to 92% of the right eyes and to 86% of the left eyes.Conclusions
The incidence of unreliable results in FDT perimetry of the second-tested left eye was higher than that of the first-tested right eye when tests were performed without a rest interval. However, the incidence of unreliability in the eye was decreased when the retest was performed after a 5-min rest interval.?Jpn J Ophthalmol 2006;50:380–382 © Japanese Ophthalmological Society 2006 相似文献998.
Shiraishi K Miyata K Houshuyama S Imatanaka N Umano T Minobe Y Yamasaki K 《Archives of toxicology》2006,80(1):10-16
We performed a 28-day repeated-dose toxicity study of diethylphthalate based on the draft protocol of the “Enhanced OECD Test
Guideline 407” to investigate whether it has endocrine-mediated properties according to this assay. Diethylphthalate was orally
administered to SD rats at doses of 0, 40, 200, and 1,000 mg/kg/day for at least 28 days, but no endocrine-mediated effects
were detected based on any of the parameters examined, suggesting that diethylphthalate does not possess endocrine properties
according to this assay. 相似文献
999.
Shinagawa N Taniguchi M Hirata K Katsuramaki T Mizukuchi T Mashita K Ushijima Y Ushida T Ishikawa S Aikawa N Yo K Mizuno A Takayama T Sato T Kato K Kubo S Suehiro S Yura J Fujimoto M Manabe T Takeyama H Tanimura H Taniguchi K Hasegawa M Yamaue H Ohnishi H Tanaka N Iwagaki H Kimura H Tsumura H Fuchimoto S Yokoyama T Sueda T Takesue Y Takeuchi H Yasui Y Hiyama E Ikeda S Yasunami Y 《The Japanese journal of antibiotics》2006,59(2):72-116
Tendency of isolated bacteria from infections in general surgery during the period from April 2004 to March 2005 were investigated in a multicenter study in Japan, and the following results were obtained. In this series, 645 strains including 17 strains of Candida spp. were isolated from 226 (79.0%) of 286 patients with surgical infections. Three hundred and seventeen strains were isolated from primary infections, and 345 strains were isolated from postoperative infections. From primary infections, anaerobic Gram-positive bacteria and anaerobic Gram-negative bacteria were predominant, while aerobic Gram-positive bacteria were predominant from postoperative infections. The isolation rate of aerobic Gram-positive bacteria, such as Enterococcus spp. and Staphylococcus aureus were higher from both types of infections. Among anaerobic Gram-positive bacteria, the isolation rate of Peptostreptococcus spp. was the highest from both types of infections. Among aerobic Gram-negative bacteria, Escherichia coli was the most predominantly isolated from primary infections, followed by Pseudomonas aeruginosa, Klebsiella pneumoniae and Citrobacter freundii in this order, and from postoperative infections, P. aeruginosa was the most predominantly isolated, followed by E. coli, E. cloacae, and K. pneumoniae. Among anaerobic Gram-negative bacteria, the isolation rate of Bacteroides fragilis group was the highest from both primary infections followed by Bilophila wadsworthia. While the isolation rate of B. fragilis group was also the highest from postoperative infections, the following bacteria were Bacteroides thetaiotaomicron and B. wadsworthia in this order. In this series, we noticed no vancomycin-resistant Gram-positive cocci, but a few strains of moderately arbekacin-resistant MRSA. Carbapenem-resistant P. aeruginosa but not multidrug-resistant was seen in 13.3 per cents. Also cefazolin-resistant E. coli probably producing extended spectrum beta-lactamase was seen in 7.0 per cents. We should be carefully followed up the facts that an increasing isolation rates of B. fragilis group and B. wadsworthia which were resistant to both penicillins and cephems. 相似文献
1000.