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891.
Inhibition of spontaneous formation of lung tumors and rhabdomyosarcomas in A/J mice by black and green tea 总被引:11,自引:0,他引:11
We investigated the effects of black tea (BT) and green tea (GT) infusion
on the spontaneous formation of lung tumors and rhabdomyosarcomas in A/J
mice. Female A/J mice, 6 weeks of age, were allocated into five groups (50
per group) and were given the following as the sole source of drinking
fluid: (i) deionized water (control group), (ii) 0.5% BT, (iii) 1% BT, (iv)
2% BT and (v) 1% GT. After 60 weeks, the mice were killed by decapitation.
Lung tumor incidence, multiplicity and volume were significantly lower in
the 2% BT group as compared with the controls (27 versus 52%, 0.33 versus
0.72 tumors/mouse and 4.27 versus 38.3 mm3, respectively). The 1% GT group
had significantly lower lung tumor multiplicity (0.41/mouse), while the 1%
BT group had significantly decreased tumor volume (7.17 mm3).
Rhabdomyosarcomas were found in 34% of the mice in the control group, and
both the 1 and 2% BT groups had significantly lower incidences at 13 and
14%, respectively. The mice in the 2% BT group weighed 16% less than those
in the control group, although they consumed more food than the control
group. The other tea-consuming groups also weighed less than the control
group (7.8-11%) while consuming more food and fluid. In a separate
experiment, similar carcinogenesis inhibition was also observed in female
A/J mice that were given 0.6% and then 0.3% instant black tea for 52 weeks.
These results demonstrate the inhibitory activity of BT against the
spontaneous formation of lung tumors and rhabdomyosarcomas in mice.
相似文献
892.
A 2-month-old, former 28-week premature infant with brochopulmonary dysplasia infected with respiratory syncytial virus was treated with nitric oxide and high frequency oscillatory ventilation after conventional therapy failed. Nitric oxide and high frequency oscillatory ventilation rapidly improved oxygenation allowing recovery without the need for extracorporeal membrane oxygenation. This treatment regimen should be considered as an option in high-risk infants with respiratory syncytial virus infection who meet extracorporeal membrane oxygenation criteria. 相似文献
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895.
The optimal regimen for investigating children with urinary tract infection (UTI) remains uncertain. Ultrasonography, contrast micturating cystourethrography (MCU), intravenous urography (IVU), and technetium-99m dimercaptosuccinic acid (DMSA) studies were performed in 58 children with UTI under 14 years of age attending two teaching hospitals and the results compared. All four investigations were normal in 12 children. In 36 with vesicoureteric reflux (VUR) on MCU, dilatation was reported on ultrasonography in eight children. Radiological renal scarring was seen in 20 children; it was suspected on ultrasonography in nine, with dilatation alone in four, and a normal report in seven. Duplex kidneys identified on IVU were unrecognised on ultrasonography or DMSA studies; ultrasonography showed no change corresponding to presumed acute defects on DMSA studies that later resolved. Disparities were observed at all ages. This study suggests that ultrasonography is unreliable in detecting VUR, renal scarring, or inflammatory change and, alone, is inadequate for investigating UTI in children. 相似文献
896.
E. P. Girardin M. E. Berner G. E. Grau S. Suter G. Lacourt L. Paunier 《European journal of pediatrics》1990,149(9):645-647
Tumour necrosis factor- (TNF-) is an important mediator in the pathogenesis of Gram-negative shock. In order to assess the role of TNF- as a marker of the severity of infections in the neonates, serum TNF- concentrations were determined at the time of septic work-up in 69 newborns (gestational age: 28–40 weeks). Nine patients had systemic infection (group A), four of them with signs of circulatory failure. Eleven patients had positive cultures of gastric aspiration or placental smears (group B) and 49 patients had completly negative septic work-up. Patients of group A had significantly more elevated serum TNF- levels than patients of group B and C. Within group A, patients with circulatory failure had mean serum TNF- concentration of 2165±817 pg/ml versus 27±8 pg/ml in newborns without shock. Serum TNF- concentrations of more than 15 pg/ml detected systemic infections in eight out of nine patients. The specificity was 98% (1 elevated TNF- concentration out of 60 non infected patients). These data indicate that premature neonates and term newborns are able to produce TNF- when they are infected. Highly elevated TNF- concentrations are found in severe systemic infections causing cardiovascular impairment. 相似文献
897.
The purpose of the study was to investigate the effect of low doses of dopamine in children. Fourteen cases were studied after open heart surgery. Cardiac output and renal parameters were determined under baseline conditions and under continuous infusion of dopamine 2.5 and 5 micrograms/kg/min. During the control period cardiac index was 2.62 +/- 0.19 L/min/m2, renal plasma flow was decreased at 269 +/- 41 mL/min/1.73 m2, GFR was 86.6 +/- 9.2 mL/min/1.73 m2, and filtration fraction was elevated at 37.1 +/- 1.9%. Plasma concentration of aldosterone correlated with the filtration fraction. At 5 micrograms/kg/min dopamine increased significantly cardiac output, renal plasma flow, and to a lesser extent GFR, thus decreasing the filtration fraction. At 2.5 micrograms/kg/min dopamine, increased renal plasma flow only in patients older than 5 y and had no effect on the other parameters. The increase of cardiac output in response to dopamine was abolished by propranolol pretreatment. By contrast, the hemodynamic renal response to dopamine was not altered by beta-blockade. These results indicate that 5 micrograms/kg/min of dopamine could prevent renal failure after open heart surgery in children by increasing renal blood flow and attenuating renal compensatory mechanisms. 相似文献
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