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101.
Melanin concentrating hormone (MCH) is a peptide synthesized in the lateral hypothalamus which stimulates food ingestion and leptin secretion in rodents. In this experiment, we measured the expressions of MCH as well as of its receptor (SLC-1) in the hypothalamus of obese hyperphagic and lean Zucker rats by quantitative real time RT-PCR. MCH mRNA expression in the obese rats was significantly increased by a factor of five (P<0.01) whereas expression of SLC-1 was decreased by more than 50% (P<0.05). Circulating levels of leptin and MCH were increased in the plasma of obese Zucker rats when compared to lean rats (38-fold and 1.7-fold, respectively, P<0.001 and P<0.01). However, individual MCH levels were not directly correlated to leptin levels in the lean (functional leptin receptor) or in the obese (non-functional leptin receptor) Zucker rats. These results indicate that the absence of leptin signaling in rats is associated with an increased hypothalamic expression and circulating release of MCH, contributing to their obesity syndrome. 相似文献
102.
Spence MM Rubin SM Dimitrov IE Ruiz EJ Wemmer DE Pines A Yao SQ Tian F Schultz PG 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(19):10654-10657
The detection of biological molecules and their interactions is a significant component of modern biomedical research. In current biosensor technologies, simultaneous detection is limited to a small number of analytes by the spectral overlap of their signals. We have developed an NMR-based xenon biosensor that capitalizes on the enhanced signal-to-noise, spectral simplicity, and chemical-shift sensitivity of laser-polarized xenon to detect specific biomolecules at the level of tens of nanomoles. We present results using xenon "functionalized" by a biotin-modified supramolecular cage to detect biotin-avidin binding. This biosensor methodology can be extended to a multiplexing assay for multiple analytes. 相似文献
103.
Balkan Endemic Nephropathy (BEN), first described in 1956 in Vratza region, Bulgaria, may result from prolonged, chronic exposure to environmental toxicants, but the underlying etiologic factors remain elusive. There has been no recent systematic characterization of the epidemiology of this disease. Recently, it has been suggested that the incidence of the disease is decreasing. We therefore abstracted data from registers of patients in 21 affected villages and the town of Vratza, Bulgaria maintained from 1964 through 1987. In 1964, the prevalence of BEN was 6.0 per 1000 inhabitants; among residents of the affected villages, the prevalence was 12.3 per 1000. From 1965 to 1975 the incidence rate was 0.7 per 1000 person-years, and from 1976 to 1987 the incidence rate was 0.3 per 1000 person-years (rate ratio 0.43; p < 0.001). Incidence was much lower in Vratza town; among residents of affected villages, the period-specific rates were 1.7 and 0.8 per 1000 per year, respectively (rate ratio 0.47; p < 0.01). These trends were consistent across all villages for which registers were maintained. Median survival following registration increased from 2.0 to 5.0 years over the same period (p < 0.001). BEN appears to be decreasing in incidence in this region. 相似文献
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106.
The aim of the study is to monitor fetal oxygen saturation--SpO2 during uncomplicated labour; to assess normal values and compare them to the data from fetal blood analysis and from clinical finding in the newborn. The study includes 53 pregnant women in term during active labour without evidence of fetal distress. Study is carried out with Nellcor-N 400--a system for measuring fetal pulse oxymetry and fetal pulse rate; oxygen sensor FS-14 and printer P-400 /Nellcor Bennet Incorporation/. Fetal pulse rate is monitored by cardiotograph Hewlett Packard. Mean duration of monitoring during first stage of labour is 98 +/- 48 min, versus 37 +/- 11 min during second stage. Mean values of SpO2 are 48.8 +/- 10% during the first stage of labor v/s 46 +/- 9.6% during second stage. Baby is born in good health--Apgar score more than 7 and mean pH value from umbilical artery 7.25. The conclusion is made that pulse oxymetry is an easy non invasive method for fetal monitoring without side effects concerning woman on labour and fetus. A relatively large range of variations of normal values is observed. 相似文献
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108.
Balansky R Gyosheva B Ganchev G Mircheva Z Minkova S Georgiev G 《Cancer letters》1999,147(1-2):125-137
Fermented milk products might be used for cancer chemoprevention due to their putative anticarcinogenic and antitumor activities. The diet was supplemented with freeze-dried milk fermented by Lactobacillus bulgaricus strain LBB.B 144 (product FFM.B 144) added throughout the experiment at doses of 1.3 g and 2.5 g per rat, 5 times a week starting 3 weeks before the first carcinogen injection. This treatment significantly inhibited, by 26.2-28.6% and by 34.2%, the total intestinal carcinogenesis induced by 1,2-dimethylhydrazine (DMH, 21 mg/kg, s.c., once per week for 20 weeks) in male and female BD6 rats, respectively. FFM.B144 decreased the tumor incidence and multiplicity in large bowel, caecum, and duodenum. Protective effects were better expressed in female animals, with exception of that observed in duodenum. Supplementation of diet with freeze-dried milk fermented by Lactobacillus bulgaricus strain LBB.B5 (product FFM.B5) inhibited DMH-induced carcinogenesis only in the large bowel, but had no significant protective effect when all intestinal tumors were taken into account. However, both freeze-dried products favorably shifted the differentiation of large bowel tumors by increasing the proportion of benign and highly differentiated malignant tumors and decreasing in parallel the number of poorly differentiated carcinomas without influencing the tumor size. A lower number of cases with visible mesenterial metastasis was also observed in FFM-treated rats. In addition, both FFM.B 144 and FFM.B5 significantly inhibited, by 26-33%, the induction in the same rats of ear-duct tumors. FFM.B144 but not FFM.B5 was also effective in inhibiting the tracheal carcinogenesis induced in Syrian golden hamsters by diethylnitrosamine (DEN, 100 mg/kg, two s.c. injections), the protective effect being better expressed in female animals. The anticarcinogenic potential of some fermented milk products might be exploited in chemoprevention of cancer in humans. 相似文献
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110.
Mechanisms of the angiotensin II effects on exploratory behavior of rats in open field. III. Modulatory role of GABA 总被引:1,自引:0,他引:1
V Georgiev D Getova M Opitz 《Methods and findings in experimental and clinical pharmacology》1991,13(1):5-9
The effects of the octapeptide angiotensin II (AT II) and its interactions with GABA (gamma-aminobutyric acid) on the exploratory behavior of male rats in open field were studied. AT II (0.1 and 0.5 microgram i.c.v.) increased the open field behavior, mainly ambulation and rearing. GABA (100 micrograms i.c.v.) significantly reduced the effects of AT II. This influence of GABA was potentiated by subconvulsive doses of bicuculline. Our results demonstrate that the GABAergic system exerts an inhibitory control on pathways mediating the stimulatory effects of AT II on exploratory behavior in open field. The data also suggest close interactions between GABA AT II receptors. 相似文献