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1.
蜂胶对糖尿病大鼠血糖的影响   总被引:2,自引:0,他引:2  
将复制糖尿病模型的 72只SD大鼠随机分为模型组 ,蜂胶水提液低剂量组、高剂量组 ,蜂胶醇提液低剂量组、高剂量组和阳性对照组 (拜糖苹 ) ,另取 12只为正常组。除正常组和模型组外 ,各组分别给予不同的试验药物。给药过程中 ,每周取血一次 ,测空腹血糖 ,给药 7周后 ,取血测定空腹血糖和果糖胺。试验结果表明 ,蜂胶水提液和醇提液均能控制糖尿病大鼠空腹血糖的升高 ,并且随着时间的延长效果越来越明显。  相似文献   
2.
Fasted Brazilian squirrel monkeys (BrSMs) exhibited slightly higher serum bilirubin levels (0.30±0.05 mg/dl) than others in the fed state (0.13±0.01). The mean liver weight was 50% lower following a 22 h fast. The rate of bile flow was unaffected by fasting and averaged 13.8 l/min/kg and 47.5 l/min/100g liver in six BrSMs. No significant difference in mean bilirubin excretion/min was observed on a body weight basis following fasting. When the mean rate of bilirubin excretion was calculated as a function of liver weight, a two-fold higher rate was present in fasted monkeys, but only at the p=0.06 level of statistical significance. From data collected in this and earlier studies, it would appear that BrSMs represent the best animals studied to date to serve as experimental controls in comparative studies with Bovilian squirrel monkeys which exhibit a Gilbert-like syndrome.  相似文献   
3.
Serum concentrations of glucose, cholesterol, triglycerides, and serum alkaline phosphatase activity were measured over different periods of time of food deprivation in male rats. Thirty percent of non-fasted rat's sera was found to be lipemic. At 16 hours of fasting, glucose levels dropped by 30% compared to the level of the non-fasting control group, and remained at a relatively constant level for up to 48 hours of fasting. Triglyceride concentrations decreased at 16 hours after fasting. Serum cholesterol levels were not changed at any of the fasting periods compared to the non-fasted control group. Alkaline phosphatase activity was decreased at 8 hours of fasting, with further declines in activity of the serum enzyme seen at 16, 24, and 48 hours of fasting. It was concluded that at 16 to 18 hours fasting, a non-absorptive state had been reached in male rats.  相似文献   
4.
Temporal changes in growth, plasma thyroid hormone, cortisol, growth hormone (GH) and non-esterified fatty acid (NEFA) concentrations, hepatic T3 content and hepatic 5-monodeiodinase activity were measured in rainbow trout (Oncorhynchus mykiss) subjected to a sustained fast for up to eight weeks, and during a four-week re-feeding period. The purpose of the study was to examine aspects of the endocrine control of energy partitioning processes characteristic of short-term (acute; fasting) and long-term (chronic; starvation) food-deprivation states in fish, and to explore the role of the thyroid hormones, cortisol and GH in the energy repartitioning that takes place during an acute anabolic (re-feeding) state following chronic food deprivation.Differences in growth rate between fed and fasted groups were evident after two weeks, but significant weight loss by the fasted groups was not evident until between four and six weeks into the fast. Hepatosomatic indices (HSIs) were significantly reduced in the fasted fish within seven days, and as early as two days in one study; recovery of the HSI in fasted fish was evident within three days of re-feeding. Liver protein content (expressed as % wet weight) was consistently depressed in the fasted fish in only one of the three studies. Liver total lipid content (expressed as % wet weight) was depressed in the fasted fish within two days of food deprivation. Because of the rapid and sustained decrease in the HSI of fasted fish, the hepatic total protein and lipid reserves, when considered on a body weight basis, were markedly lowered within the first few days of the fast. Plasma GH concentrations exhibited a bi-modal pattern of change, with a transient fall in levels, followed by a sustained increase in fasted fish. The indicators of interrenal activity were suggestive of a depressed pituitary-interrenal axis in fasted animals; plasma cortisol levels were elevated to levels of fed animals within one day of re-feeding. The indicators of thyroid hormone economy (plasma thyroid hormone levels, liver triiodothyronine content, hepatic 5-monodeiodinase (MD) activity, thyroid epithelial cell height) were similarly indicative of a depressed pituitary-thyroid axis in fasted animals, with recovery to levels of the fed animals within one week. Despite the compensatory changes in accumulation of reserves (as indicated by a compensatory increase in HSI), there were no apparent compensatory changes in any of the endocrine parameters evident during the re-feeding period.  相似文献   
5.
Two groups of Atlantic salmon post-smolts previously fed diets either unsupplemented or supplemented with Zn, Fe, Cu and Mn were fasted for 6 weeks in order to study the reliability of tissue indicators of element status during fasting. The fish were weighed at 2-week intervals and samples of whole fish liver, vertebrae, serum and eyes were taken for analyses of elements by atomic absorption spectrometry.
Body weight, per cent dry matter, condition factor and haematocrit values decreased during the fasting period. The concentration of elements in whole body remained constant, indicating that whole body is a stable indicator of element status during fasting. Other tissues seemed to be more sensitive (i.e. hepatic Fe concentration and vertebrae Zn and Mn concentrations). The serum concentrations of the elements generally decreased during fasting, especially for P and Zn. Element concentrations in whole body and most tissues during fasting were generally more dependent upon initial element status than on the fasting itself.
Care should be taken in drawing conclusions about the element status of fish based solely upon the examination of serum concentrations, and more than one tissue indicator should be used in the establishment of the element status of fish.  相似文献   
6.
采用放射免疫分析法,测定鹅外周血液中八肽胆囊收缩素样免疫活性(CCK-8LT),观察禁食和抱窝期摄食抑制状态下血浆 CCK-8LI 水平的变化.结果如下:(1)刚饲喂混合精料后,鹅血浆中 CCK-8LI显著升高,为禁食时水平的2.6倍,揭示外周血液中 CCK-8LI 在鹅摄食活动的短期调节中起作用;(2)在持续4周的抱窝期内,母鹅血浆 CCK-8LI 显著低于醒抱后恢复期水平.血浆中 CCK-8LI 是否参与鹅抱窝期摄食抑制的调控,有侍进一步研究.  相似文献   
7.
The influence of the quality and quantity of diets on the disposition kinetics of albendazole were studied in sheep in two different experiments. The plasma concentration profiles of albendazole sulphoxide and albendazole sulphone were measured following intraruminal administration of albendazole at 5.0 mg/kg body weight in weaner sheep offered three different diets: 100% green Sorghum spp., 100% dry mature Cenchrus ciliaris hay and a 50:50 mix of these two diets. The peak plasma concentrations and the availability of the albendazole metabolites, as measured by the area under the concentration–time curve, were significantly higher (p<0.01) in the animals offered exclusively dry fodder compared to other diets. Changing the diet from dry to green fodder resulted in a significantly lower systemic availability of the drug metabolites. It is suggested that a decreased transit time of the digesta in the bowel on the green diet, with its high water content, limited the systemic availability of the drug by reducing the time available for gastrointestinal absorption.An experiment on the influence of different levels of pretreatment fasting on the pharmacokinetics of albendazole revealed significantly higher (p<0.05) plasma concentrations of the anthelmintically active sulphoxide metabolite from 12 h onwards following administration of the drug in animals subjected to 24 h of pretreatment fasting compared to other groups with pretreatment fasting of 8, 12 or 18 h. The area under the concentration–time curve and the minimum residence time of the drug metabolites were significantly greater (p<0.05) in animals that had been fasted for 24 h. It is suggested that fasting induces a decrease in the flow of digesta through the gastrointestinal tract of ruminants and prolongs the duration of dissolution of the drug, resulting in enhancement of the absorption of albendazole and of the systemic availability of its metabolites.  相似文献   
8.
Historically, intermittent fasting (IF) has been considered as an effective strategy for controlling the weight of athletes before competition. Along with excellent insight into its application in various spaces by numerous studies, increasing IF-mediated positive effects have been reported, including anti-aging, neuroprotection, especially obesity control. Recently, the gut microbiota has been considered as an essential manipulator for host energy metabolism and its structure has been reported to be sensitive to dietary structure and habits, indicating that there is a potential and strong association between IF and gut microbiota. In this paper, we focus on the crosstalk between these symbionts and energy metabolism during IF which hold the promise to optimize host energy metabolism at various physical positions, including adipose tissue, liver and intestines, and further improve milieu internal homeostasis. Moreover, this paper also discusses the positive function of a potential recommendatory strain (Akkermansia muciniphila) based on the observational data for IF-mediated alternated pattern of gut microbiota and a hopefully regulatory pathway (circadian rhythm) for gut microbiota in IF-involved improvement on host energy metabolism. Finally, this review addresses the limitation and perspective originating from these studies, such as the association with tissue-specific bio-clock and single strain research, which may continuously reveal novel viewpoints and mechanisms to understand the energy metabolism and develop new strategies for treating obesity, diabetes, and metabolic disorders.  相似文献   
9.
Background: Fasting is an important preanalytical factor that may affect the interpretation of hematology and clinical biochemistry data in toxicology or pharmacology studies. Limited information is available on how the results may be affected by different durations of fasting. Objective: The purpose of this study was to assess the influence of fasting duration on clinical pathology results in male and female rats and to determine an optimum fasting time for preclinical studies. Methods: Male and female Wistar rats (10 each per group) were fasted for 0, 4, 8, 16, 24, and 48 hours. Changes in body weight and in the results of routine CBC and clinical chemistry analysis were evaluated by 1‐way ANOVA. Results: Body weight was significantly decreased by 4 hours of fasting in all rats, and hemoglobin concentration was significantly increased at 16 hours in male rats. Serum glucose and triglyceride concentrations in both sexes and cholesterol and high‐density lipoprotein‐C concentrations in female rats were also significantly decreased beginning at 16 hours. The creatinine concentration was increased in females after 16 hours of fasting. Serum alkaline phosphatase and alanine aminotransferase activities were significantly decreased after 8 hours in males and 16 hours in females. Conclusions: Fasting‐induced changes in clinical pathology results were consistent with hemoconcentration and altered nutrition and metabolic function. Most changes occurred at 16 hours, with minimal subsequent changes. Hence, a 16‐hour fasting duration may be recommended for preclinical studies involving clinical pathology measurements.  相似文献   
10.
The effects of fasting on the quality of the dorsal and ventral ordinary muscles from cultured Pacific bluefin tuna (Thunnus orientalis) during chilled storage were investigated. Tuna were subjected to fasting for 2 days in the summer or 6 days in the winter prior to harvesting. The breaking strength of the dorsal ordinary muscle sampled in the summer increased until 24 h and then decreased. There were no significant differences in the lipid and glycogen content of the ordinary muscle after 9 h of storage between the controls and either fasting group. The pH of the ordinary muscle subjected to summer and winter fasting was higher than in the controls after 24–48 h of storage. However, the relationship between the pH and glycogen content was unclear. The metmyoglobin content during chilled storage was lower in the ordinary muscles from either fasting group than in the controls. In conclusion, fasting for 6 days in the winter improved the color stability of the ordinary muscle without a decline in its lipid content.  相似文献   
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