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101.
We examined the effects of the immunosuppressant tacrolimus (FK506) on the discrimination learning impairment induced by chronic cerebral hypoperfusion in rats. Chronic cerebral hypoperfusion was prepared by permanent ligation of bilateral common carotid arteries for male Wistar rats aged 9 weeks. FK506 (0.05 mg/kg, s.c.) recovered the learning impairment and also prevented the rarefaction of white matter and striatal neuronal cell damage. Our findings suggest that FK506 ameliorates the learning impairment mainly due to preventing neuropathological alterations.  相似文献   
102.
103.
We evaluated the effects of the erbium:YAG laser (2.9 m wavelength) on ocular structures. Energy was successfully transmitted through a fiberoptic bundle for intraocular and extraocular applications. The wavelength was strongly absorbed by ocular tissues, producing ablations with minimal thermal damage. Our results indicated that the erbium: YAG laser may have potential uses as a photoablative tool to reshape the corneal surface and as a surgical knife.  相似文献   
104.
Prostaglandin E2 (PGE2) is a key regulator of gastrointestinal, immunological, and mucosal homeostasis. Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit the prostaglandin-producing enzyme cyclooxygenases (COXs), and can induce serious complications, such as gastrointestinal damage, with long-term treatment. Orengedokuto (OGT), a Japanese traditional herbal medicine (Kampo medicine), is effective in various animal models of enteropathy. In the present study we examined whether OGT prevents enteropathy induced by NSAIDs in mice. Ulceration in the small intestine was induced with 2 subcutaneous injections of indomethacin (20 mg/kg body weight). Orally administered OGT prevented or reduced lethality, intestinal lesions, bleeding, increased serum nitrate/nitrite levels, and reduction of mucosal PGE2 induced by indomethacin. These beneficial effects of OGT were accompanied by increased production of PGE2 and interleukin 10 by isolated lamina propria mononuclear cells; COX-2 in these cells may be a major source of PGE2 in normal intestines. These findings suggest that OGT could be an effective therapeutic agent for the treatment of inflammatory bowel disease and adverse reactions to NSAIDs.  相似文献   
105.
We examined the source of Ca(2+) involved in the volume regulation of Madin-Darby canine kidney (MDCK) cells with confocal microscopy and fluoroprobes. Hyposmosis induced a transient increase in cell volume, as well as cytoplasmic Ca(2+), which peaked at 3 to 5 min and gradually decreased to reach the initial value within about 30 min. This late decrease in cell volume, as well as the transient rise in cytoplasmic Ca(2+), was reduced in Ca(2+)-free solution and was abolished by pretreatment with thapsigargin. In conclusion, Ca(2+) released from the intracellular store contributes to the regulatory volume decrease following hyposmotic swelling in MDCK cells.  相似文献   
106.
107.
Estrogenic activity of phthalate esters in dental soft resins was evaluated with an amphibian system consisting of a vitellogenin (VTG)-detecting Enzyme-Linked Immunosorbent Assay and a primary-cultured hepatocyte assay using adult male Xenopus laevis. In particular, phthalate esters--Di-n-butyl phthalate (DBP), Butyl phthalyl butyl glycolate (BPBG), Benzyl butyl phthalate (BBP), and Benzyl benzoate (BB)--were investigated. Bisphenol A (BPA) was prepared for comparison with these chemicals, and 17beta-estradiol (E2) was used as a positive control. The chemicals were diluted in dimethyl sulfoxide (DMSO) to obtain final concentrations ranging from 10(-11) to 10(-4) mol/l. BPA induced estrogenic activity at a concentration of 1.1x10(-6) mol/l, while E2 showed at 4.1x10(-11) mol/l. DBP, BBP, BB, and BPBG showed no estrogenic activity at concentrations between 4x10(-7) mol/l and 1x10(-4) mol/l. The latter result indicated that these phthalate esters might be metabolically transformed into non-estrogenic substances in Xenopus hepatocytes. Furthermore, this study demonstrated that through in vitro metabolism assessment, the estrogenic activity of chemical substances could be directly detected in terms of VTG secretion in primary-cultured Xenopus hepatocytes.  相似文献   
108.
109.
The current study evaluates the indices of glucose control for diabetics (i.e., glycated albumin (GA), hemoglobin A1c (HbA1c), plasma glucose (PG) and immuno-reactive insulin (IRI)) in non-diabetic children from a population-based cohort, and compares those values according to the presence of obesity to examine any differences in these indices. GA, HbA1c, casual PG and casual IRI in obese children (n = 209) were compared to those of non-obese children (n = 1060) in Ina town, Saitama Prefecture, in 2002-2003. In obese children, the levels of HbA1c, PG and IRI were statistically higher when compared to those of non-obese children. In contrast, the median and intra-quartile range (IQR) of GA of obese children (13.6%: 12.6-14.7) was statistically lower when compared to that of non-obese children (14.3%: 13.5-15.4, p < 0.001). The low GA (%) in obese children is mainly due to the low absolute value of GA (g/dl) rather than a higher albumin value (g/dl). This is the first report to reveal that GA levels are low in obese, non-diabetic children. Additional data collection and an experimental approach are necessary to reveal the reasons behind lower GA levels in obese children.  相似文献   
110.
BACKGROUND: Sleep-disordered breathing (SDB) can be one of the major determinants of high blood pressure (BP), but there has been no study on SDB with an emphasis on shift workers. The objective of this study was to examine whether a relationship between SDB and blood pressure/hypertension is more evident among shift workers than among day workers. METHODS: In this cross-sectional study, we measured BP levels and oxygen desaturation index (by nocturnal pulse oximetry) among 253 male shift workers and 206 male day workers aged 30 to 62 years at nuclear power plants in Japan. RESULTS: The prevalence of SDB (3% oxygen desaturation index >or=10 and >or=15 per hour) in all subjects was 11.3% (95% confidence interval [95% CI] 8.4-14.2) and 6.1% (95% CI 3.9-8.3), respectively, with no statistical difference between shift and day workers. Systolic and diastolic BP levels were correlated with 3% oxygen desaturation index in all subjects after adjustment for potential confounding variables. This association was primarily observed among workers aged >or=40 years, more specifically older shift workers. CONCLUSIONS: A correlation between SDB severity and diastolic BP levels among shift workers aged >or=40 years suggests the importance of screening for SDB among shift workers for BP control.  相似文献   
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