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991.
Altered serum immunoglobulin response to model intestinal antigens during dietary exposure to vomitoxin (deoxynivalenol) 总被引:1,自引:0,他引:1
The effect of dietary vomitoxin on the serum IgA and IgG responses to two model intestinal antigens, casein and cholera toxin (CT), were assessed in 4 experimental groups: (1) mice fed casein-based diet, (2) mice fed casein-based diet containing 25 ppm vomitoxin, (3) mice fed casein-based diet and immunized with CT, and (4) mice fed casein-based diet containing 25 ppm vomitoxin and immunized with CT. Unimmunized and CT-immunized mice that were fed vomitoxin exhibited increased levels of total serum IgA relative to matched control animals fed the standard diet. Relative concentrations of casein-specific IgA were greater in both unimmunized mice and CT-immunized mice fed standard diet with vomitoxin than in matched controls fed standard diet only. CT-specific serum IgA in CT-immunized mice was not affected by vomitoxin feeding, but relative levels of CT-specific IgA were higher in unimmunized mice fed vomitoxin than in unimmunized mice fed standard diet. Both casein- and CT-specific serum IgG were depressed in mice fed vomitoxin. Significant differences in total, casein-specific and CT-specific IgA within the intestinal contents were not observed between CT-immunized mice fed vomitoxin and those fed the control diet. The results suggest that vomitoxin altered regulation of the normal immunoglobulin response to intestinal antigens and that this was manifested in the systemic compartment. 相似文献
992.
A Kubota A Okada K Imura H Kawahara R Nezu S Kamata Y Takagi 《Journal of pediatric surgery》1990,25(6):618-621
The effect of metronidazole (MNZ) on hepatic dysfunction associated with total parenteral nutrition (TPN) in neonates was investigated. Neonates receiving TPN for more than 2 weeks were divided into three groups. In group 1, TPN was given alone, in group 2, 25 mg/kg/d of MNZ was administered intravenously for the first 2 weeks of TPN, and in group 3, 50 mg/kg/d of MNZ was given for the first 3 weeks of TPN. Several parameters of liver function tests (LFTs) during the first 4 weeks of TPN were compared among these three groups. There was no significant difference of these parameters between group 1 and group 2. Although there was no significant difference of alkaline phosphatase, gamma-glutamyl transpeptidase, direct bilirubin, and total bile acid between groups 1 and 3, transaminase (glutamic oxaloacetic, glutamic pyruvic) of group 3 remained significantly lower than those of group 1. In conclusion, the administration of MNZ 50 mg/kg/d for 3 weeks, at least, prevented the elevation of transaminase during TPN in neonates, suggesting the possible involvement of intestinal anaerobic flora in the pathogenesis of TPN-associated liver dysfunction. 相似文献
993.
From 1979 to 1987 1428 patients with blunt abdominal trauma were treated in the Department of Surgery of the University of Freiburg; 119 patients had intestinal injuries. They were mainly young adults who had sustained a car accident. 71.3% of the small bowel injuries were overseen, 14.2% needed resection, and in 14.5% an operative procedure was not necessary. The surgical procedure for colonic injuries has to be chosen with regard to the age and general condition of the patient, to the severity of the trauma, to associated injuries and to the stage of peritonitis. Accordingly, 18% of the patients were treated with and 58% without a protective colostomy, 24% could be treated conservatively. Mortality and morbidity correlated with the severity of associated injuries. Morbidity was also dependent on the time interval between accident and operative therapy. 相似文献
994.
Uptake of Adriamycin in tumour and surrounding brain tissue in patients with malignant gliomas 总被引:1,自引:0,他引:1
H. von Holst E. Knochenhauer H. Blomgren V. P. Collins L. Ehn M. Lindquist G. Norén C. Peterson 《Acta neurochirurgica》1990,104(1-2):13-16
Summary Eight patients with malignant gliomas verified on CT scan, received an intravenous injection of 50 mg of Adriamycin R, 24 hours prior to surgical removal of the tumour. Peroperatively, both tumour and surrounding tissue specimens were obtained for determination of the tissue concentrations of Adriamycin and its reduced metabolite Adriamycinol. It was found that Adriamycin could be detected in tumour tissue from all patients. The concentration varied between 0,9 and 4,6 nmol/g tissue. In contrast, Adriamycin could only be detected in surrounding brain tissue from one patient.In anin vitro study a human malignant glioma cell line (U-251 MG) was exposed to various concentrations of Adriamycin for 24 hours. It was found that an intracellular drug concentration above 30 nmol/g cells caused a concentration dependent inhibition of cell growth. Thus, it is likely that the poor effect of Adriamycin on patients with malignant gliomas is due to an ineffective drug accumulation in the tumour tissue. 相似文献
995.
Effects of the MAO-A-inhibitor brofaromine (BRO), 10 mg/kg po after repeated (twice daily for 14 days) administration on the spontaneous behavior (exploratory and basal locomotor activities) and the exploratory activity modified by methoxamine, clonidine and d-amphetamine in male Wistar rats were studied in both light and dark phases of a diurnal cycle (L: 0700-1900 h). After single administration BRO in the light phase had no effects. In the dark phase BRO decreased the exploration (62% of control, p less than 0.01), increased the clonidine-evoked hypoactivity and amphetamine-evoked hyperactivity. The L-D differences occurred also after repeated administration. BRO in the light phase did not influence the exploration, decreased basal locomotor activity, did not change methoxamine and clonidine action and potentiated the action of amphetamine. In the dark phase, however, it did not influence the exploration and basal locomotor activity, intensified the methoxamine effect, and did not change the clonidine and amphetamine actions. The results demonstrate that the effects of BRO on behavior in rats: 1) differ from the effects caused by other antidepressants which are not MAO inhibitors; 2) are phase-dependent after both single and repeated administration. 相似文献
996.
A new range of stand magnifiers has been released by the COIL company in the United Kingdom. Examination of these magnifiers reveals that they fail to deliver the rated magnifications labelled prominently on the appliances, as a result of the manufacturer's conformance with the requirements of the German DIN standard and the use of back vertex power (F'v) rather than equivalent dioptric power (Fm) of the magnifier. In this study we provide information on the optometric parameters of these new stand magnifiers that will assist the more accurate specification of improvements in vision expected from their use. 相似文献
997.
998.
Frances J. Mather Richard M. Simon Gary M. Clark Daniel D. 《Statistics in medicine》1990,9(9):1118-1118
999.
W J Scott C A Duggan C M Schreiner M D Collins 《Toxicology and applied pharmacology》1990,103(2):238-254
The effects of acetazolamide on the developing rodent limb bud were postulated to result from a reduction of intracellular pH (pHi). Embryonic intracellular pH was calculated from transplacental distribution of the weak acid, 5,5'-dimethyloxazolidine-2,4-dione, in teratogenically sensitive (C57BL/6) and resistant (SWV) inbred mice. pHi was reduced by acetazolamide treatment in C57 embryos and limb buds but not in SWV samples. Acetazolamide teratogenesis can be exacerbated by coadministration of amiloride, presumably through inhibition of Na+/H+ exchange attributable to the latter agent. pHi reduction after such treatment was more profound than after acetazolamide alone, providing further support for the central hypothesis. pH was also reduced in other embryonic (embryo plasma) and extraembryonic compartments (exocoelomic fluid, amniotic fluid). pH changes in these compartments could also lead or contribute to abnormal development. 相似文献
1000.
A Sarmiento E Ebramzadeh W J Gogan H A McKellop 《The Journal of bone and joint surgery. British volume》1990,72(6):996-1002
We reviewed the radiographs of 864 Charnley and STH (Zimmer) cemented total hip arthroplasties with a mean follow-up of seven years (maximum 16 years). Survivorship analysis was used to assess the correlation between radiographic performance and the bony containment or the coronal orientation of the acetabular cup. The cup orientation and containment were interrelated; all vertically oriented cups were completely contained, whereas 25% of more horizontal cups were only partially contained. Completely contained cups had significantly lower incidences of complete cement-bone radiolucency (p = 0.02) and of wear (p = 0.09). Vertically oriented cups had a lower incidence of continuous radiolucency than neutrally oriented cups, but this was not statistically significant (p = 0.25). Our results confirm the importance of complete bony containment, and also indicate that it is better to accept vertical orientation and obtain full bony coverage than to have a more horizontal orientation with partial containment. 相似文献