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51.
Several phytoecdysteroids have been found in the extracts ofA. multiflora andAlinerifolia using HPLC analysis. Those were 20-OH ecdysone, cyasterone. 3-acetate-20-OH ecdysone. 2-acetate-20-OH edysone, ajugalactone. We found out that those phytoecdy steroids could lead the second instar larva ofClostera anastomosis andStilpnotia candida to death. The modified mortality rate was from 44.64% to 96.24%. Those extracts could significantly reduce the amount of nymph produced by the femaleTuberolachnus salignus. The number of the nymph produced after treating with those extracts was only 20% to 70% of that produced by the untreated group. The death rate of the newly produced nymph which treated was among 33.33% to 58.82%. It was much higher than the death rate of the control group (17.57%). This research project was sponsored by the Natural Sciences Fundation of Heilongjiang Province (94003) Responsible Editor: Chai Ruihai  相似文献   
52.
Polyunsaturated fatty acid consumption has been shown to improve insulin sensitivity. We studied if administration of broth with beef meat enriched with polyunsaturated fatty acids influenced glucose‐stimulated insulin release in healthy male volunteers. Broth was made either from cattles undergone dietary supplementation with lightly bruised whole linseed in addition to feeding ad libitum on grass silage (test meal) or from those fed grass silage alone (control meal). Oral glucose tolerance tests (OGTT) were performed in patients after a 6‐day period of eating 300 ml broth containing 100 g meat once a day in addition to their otherwise normal mixed nourishment. During OGTT, blood samples were taken for blood glucose level and plasma insulin immunoreactivity before and 15, 30, 60, 90, 120, and 180 min after the glucose load. Glucose‐stimulated maximum increase in plasma insulin immunoreactivity was 42 ± 6.6 and 81 ± 7.4 mU/ml (p < 0.05) after the test and the control meals, respectively. However, both fasting and postload blood glucose levels were the same after either meal period. The results suggest an insulin‐sensitizing effect of food produced from beef cattle maintained on linseed diet in healthy human volunteers.  相似文献   
53.
Hege  Kippenes  DVM  PhD  Patrick R.  Gavin  DVM  PhD  Ronald D.  Sande  DVM  MS  PhD  Dennis  Rogers  RT  Vaughn  Sweet  MS 《Veterinary radiology & ultrasound》2003,44(6):714-719
The purpose of the study was to evaluate the accuracy and precision of a rigid positioning device for repositioning the cervical spine accurately and precisely during conformal radiation therapy of dogs. Fifteen purpose bred research dogs in a radiation therapy study were included. The dogs were positioned using a head holder and a deflatable pillow attached to the treatment table. Port films were reviewed retrospectively, and repositioning precision was recorded by measurements in three orthogonal planes of the head, 2nd cervical vertebra and 1st thoracic spinous process. Mean treatment position was compared to the planning position for a measurement of systematic set-up error. Mean interfraction position variation of the 2nd cervical vertebra was 0.2, 0.1 and 0.2 cm for the ventrodorsal, caudocranial and laterolateral directions respectively, and the average systematic set up error was 0.2, 0.1 and 0.2 cm for the ventrodorsal, caudocranial and laterolateral directions respectively. Knowledge of the magnitude of reposition errors should be included when determining the margins around the tumor.  相似文献   
54.
SUMMARY The relationships between some environmental factors and reproductive rates of dairy cattle during summer in a tropical upland area were studied using records for Holstein-Frieslan milking cows and non-lactating growing helfers maintained at the Kalri Research Station on the Atherton Tableland in north Queensland. The Station is situated in a tropical upland environment with warm, wet summers and dry, cool winters. Data were collected over a 12-year-period (1977 to 1988) for cows grazing nitrogen (N)-fertilised grass pastures and receiving either no supplement or about 3.5 kg molasses/cow/day. Cattle were mated over a 10-week period starting from mid-January to early February, with 32 to 36 cows and 5 to 42 heifers used in each year. There was considerable variation among years in the pregnancy rate after 3 Inseminations, with a low of 39% and a high of 94% pregnancy. This variation from year to year was reduced for cows grazing pastures receiving 300 kg N/ha/yr after molasses feeding commenced in 1984–85. Pregnancy rates after molasses Introduction were higher for cows grazing pastures receiving 300 compared with 100 kg N/ha/yr. Pregnancy rate in cows and heifers was reduced from 80 to 55% as mean daily maximum temperature increased from 26°C to 27.5°C. At mean maximum temperatures above 27°C for cows and 27.6°C for heifers pregnancy rates to 3 Inseminations were consistently below 60%. Much of the year to year variation in pregnancy rate was related to rainfall during the mating period. There was a positive association between pregnancy rate and rainfall up to 1000 mm, and this was associated with differences in growth rate of pasture. In years of very high rainfall, above 1500 mm, there was a depression in pregnancy rate, which may be related to the intense humidity in very wet years causing heat stress in cows and associated problems such as feet infections, or a deterioration in pasture quality. We conclude that much of the variation in pregnancy rate during summer may have been related to heat stress and the level of feed supply in the form of pasture and supplements.  相似文献   
55.
Puberty is the result of a dynamic interaction between genetic factors and environmental cues, all of which lead to the attainment of reproductive capacity. Thus, significant changes in hormone secretion occur from the pre‐pubertal to the pubertal stage. The objective of this review is to provide an update of some endocrine, physiological, metabolic and genetic concepts involved in the establishment of the hypothalamic‐hypophyseal‐gonadal axis function promoting the onset of the reproductive function during puberty. To achieve this purpose, basic aspects of the function of the hypothalamic‐hypophyseal‐gonadal axis, the control of the axis by neurotransmitters and the interaction between reproductive function and metabolic status will be considered. Finally, the role of the novel kisspeptin system and the GPR54 receptor as modulators of puberty will be considered, in addition to the hierarchical expression of the main genes acting as regulators of the onset of puberty.  相似文献   
56.
SUMMARY Four forms of salmonellosis were recognised in feedlots and during transport by sea: septicaemic, and acute, subacute and chronic enteric. The severity and distribution of lesions in the enteric forms varied according to the progression of the pathological process. The acute disease involved the abomasum and small intestine whereas the subacute disease centred on the lower small intestine and upper large intestine. Chronic disease involved considerable mucosal repair in the ileum, caecum and proximal colon. Septicaemic salmoneiiosis was often accompanied by acute enteritis and occasionally by cholecystitis. S typhimurium was the most frequently encountered serotype.  相似文献   
57.
The construction of a variable kVp, variable mA radiographic technique chart for the equine thorax using linear regression analysis is described. The independent variables in the analysis were body weight (pounds) and thoracic girth (inches) and the dependent variables were the radiographic exposure techniques (mAs, kV.p). Four areas (lateral views only) of each horse's thorax were radiographed using a focal spot-film distance (FFD) of 200 cm with the animal standing. The four views were craniodorsal, cranioventral, caudodorsal and caudoventral. For comparison, an additional caudodorsal view was made at 100 cm FFD to quantitate the decrease in exposure, the increased magnification and the decreased area of the lung exposed on the x-ray tube side of the horse compared with 200 cm FFD technique. Body weight was a satisfactory means to determine radiographic technique factors for thoracic radiographs in the horse. Thoracic girth (inches) was also measured and used to determine radiographic technique factors but was less exacting and less convenient than body weight.  相似文献   
58.
Calorie restriction (CR) without undernutrition has been found to enhance stress resistance and life span in endotherms and ectotherms. We investigated the effect of 30% reduction in food offering on growth, aerobic capacities and oxidative stress parameters in young turbot (Scophthalmus maximus, L.). No differences in body weight, length and hepatosomatic index between the ad libitum (AL)-fed and the CR group occurred after 55 days of diet application. Of the mitochondrial marker enzymes, only citrate synthase (CS) activity in the liver was reduced under CR, whereas muscle CS activity and cytochrome oxidase (CCO) activity in both tissues remained the same in both feeding groups. The concentration of reduced glutathione increased significantly during feeding in muscle of CR fish, resulting in a more reduced glutathione redox ratio (GSH/GSSG) compared with AL fish muscle. Thiobarbituric acid-reactive lipid hydroperoxides (lipid peroxidation) but not protein carbonyl content (protein oxidation) was significantly reduced in CR fish muscle. Liver oxidative stress parameters did not vary significantly between experimental feeding groups. We conclude that 30% CR over 8 weeks has no adverse effect on young turbot. On the contrary, CR supports a reduced tissue oxidation state and reduces accumulation of lipid peroxidation products in muscle at sustained muscular aerobic capacity.  相似文献   
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