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41.
Piper L. Nelson Andreas Beck Henrique Cheng 《Veterinary journal (London, England : 1997)》2011,187(2):153-164
The transient receptor potential proteins (TRPs) make up a very important family of ion channels responsible for a wide array of cellular functions. Originally identified in the visual system of Drosophila melanogaster, these channels are ubiquitously distributed throughout the mammalian system. The TRP family is divided into seven subfamilies in two groups: the first group comprises TRPC (canonical), TRPV (vanilloid), TRPM (melastatin), TRPN (Drosophila NOMPC) and TRPA (ankyrin). The second group contains TRPML (mucolipin) and TRPP (polycystin).The biophysical characterization of TRPs has revealed significantly different activation mechanisms and selectivity between channels. Functional studies have demonstrated that TRPs are necessary for a number of physiological processes, including sensation (such as taste, smell and temperature), hormone secretion and development. TRPs mediate these effects mainly by controlling the intracellular Ca2+ concentration, which acts as a second messenger. Recent research has linked TRPs to different diseases. This review considers the impact of TRPs on cell physiology and the abnormalities observed with channel dysfunction. 相似文献
42.
Alkaline phosphatase (APase) activity in tissue samples, with adherent bacteria, was measured from two sites in the rumen and from two sites in the abomasum of 57 yearling Angus and Hereford bulls and heifers fed a high or a low energy diet. In the rumen, APase activity was higher at the caudoventral blind sac than at the dorsal sac in animals of both breeds fed the high energy diet and in Angus bulls fed the low energy diet, but the reverse was observed in Hereford bulls fed the low-energy diet (P less than .01). In the abomasum, APase levels were higher for bulls than heifers (P less than .01) and higher at the fundic than at the pyloric region (P less than .01). Morphological studies also showed that rumen samples from animals fed a high energy diet exhibited a more widely distributed APase activity and an increase in the digestive recycling of epithelial cells that produced some "pitting" of the tissue. The higher APase activity of the epithelial tissue of animals fed the high energy diet may be explained by the greater rate of cell death and renewal indicated by the higher mitotic index reported by other researchers who have studied the cell cycle of the rumen epithelium in ruminants fed high and low energy diets. 相似文献
43.
蚕粪中提取叶绿素铜钠盐的稳定性研究 总被引:10,自引:3,他引:10
以蚕粪为原料,95%的乙醇为溶剂提取叶绿素,并通过化学法制得叶绿素的铜纳盐。采用721分光光度计对叶绿素铜钠盐进行定性、定量测定,确定该色素测定系统中的最大波长为414nm。通过测量吸光值研究了几种常用食品添加剂对叶绿素铜钠盐稳定性的影响,并对其耐光、耐热、耐酸碱及耐氧化性、耐还原性进行探讨。结果表明:叶绿素铜钠盐在70℃以下稳定性较好;光照对叶绿素铜钠盐稳定性的影响较大;还原剂(Na2S2O3)对叶绿素铜钠盐稳定性的影响较大,氧化剂在短时间内对其稳定性的影响不大,但放置的时间不宜超过30min;叶绿素铜钠盐在pH值为6以上的溶液中较为稳定,且有机酸及单糖对其稳定性无明显影响。 相似文献
44.
Protein and lipid sources affect cholesterol concentrations of juvenile Pacific white shrimp, Litopenaeus vannamei (Boone) 总被引:1,自引:0,他引:1
Two experiments were conducted to evaluate the effects of protein and lipid sources on cholesterol, AA, and fatty acid content, and on biological performance of juvenile Pacific white shrimp, Litopenaeus vannamei (Boone). In Exp. 1, seven isonitrogenous and isocaloric diets were prepared using fish meal; soybean meal; casein; fish meal + soybean meal; fish meal + casein; soybean meal + casein; and fish meal + soybean meal + casein. In Exp. 2, seven isonitrogenous and isocaloric diets were prepared using fish oil; soy oil; poultry fat; fish oil + soy oil; fish oil + poultry fat; soy oil + poultry fat; and fish oil + soy oil + poultry fat. Nine shrimp (average BW 570 mg) were stocked per 60-L tank, with three tanks per diet in each experiment. Shrimp were fed to apparent satiation twice daily for 28 d. Protein sources affected shrimp cholesterol, feed consumption, feed efficiency, protein consumption, protein efficiency ratio, and crude body fat (P < or = 0.05), but not weight gain, survival, hepatosomatic index, body protein, ash, and AA composition. Body (without hepatopancreas) cholesterol concentrations were the highest in shrimp fed the diet containing fish meal (0.81%), lowest for those fed the casein diet (0.64%), and intermediate in the other dietary treatment groups (range 0.71 to 0.74%). Lipid source also affected shrimp body cholesterol, body fatty acid profiles, and fatty acid profiles in the hepatopancreas (P < or = 0.05), but not growth performance, body protein, fat, ash, and cholesterol concentrations in the hepatopancreas. Shrimp fed the fish oil diet had the highest body cholesterol (0.75%), whereas those fed the soy oil or poultry fat diets were lowest (0.66 and 0.65%, respectively). Results indicate that by replacing fish meal and fish oil with soybean meal and soy oil, shrimp growth performance is not affected, but body cholesterol concentration is reduced. 相似文献
45.
Electroacupuncture-induced neural activation detected by use of manganese-enhanced functional magnetic resonance imaging in rabbits 总被引:12,自引:0,他引:12
Chiu JH Cheng HC Tai CH Hsieh JC Yeh TC Cheng H Lin JG Ho LT 《American journal of veterinary research》2001,62(2):178-182
OBJECTIVE: To investigate the effects of acupuncture on neural activity detected by use of manganese-enhanced functional magnetic resonance imaging (fMRI) and elucidate the relationship between somatic acupoint stimulation and brain activation. ANIMALS: 40 New Zealand White rabbits. PROCEDURE: Manganese-enhanced fMRI was performed in anesthetized rabbits manipulated with electroacupuncture (EA) on Zusanli (ST-36) and Yanglingquan (GB-34) acupoints. Image acquisition was performed on a 1.5T superconductive clinical scanner with a circular polarized extremity coil. T1-weighted images were acquired sequentially as follows: baseline, after mannitol injection, after manganese infusion, and 5 and 20 minutes after initiation of EA. RESULTS: Changes in focal neural activity were detected by use of manganese-enhanced fMRI. Stimulation on Zusanli (ST-36) for 5 minutes resulted in activation of the hippocampus, whereas stimulation on Yanglingquan (GB-34) resulted in activation of the hypothalamus, insula, and motor cortex. Activation became less specific after 20 minutes of EA. Furthermore, stimulation on ipsilateral acupoints led to bilateral brain activation. CONCLUSIONS AND CLINICAL RELEVANCE: Each acupoint has a corresponding cerebral linkage, and stimulation on these points resulted in time-dependent neural activation. Understanding the linkage between peripheral acupoint stimulation and central neural pathways may provide a useful guide for clinical applications of acupuncture. 相似文献
46.
诊断桑树黄化型萎缩病的新方法 总被引:1,自引:2,他引:1
本文探讨利用瑞氏染色法和旦尼氏染色法诊断桑树黄化型萎缩病的可能性。试验结果表明,用此方法,在病株枝条或主根的横切面上,韧皮部的病原寄生部位被染成兰色或青色,呈阳性反应,健株组织切片的韧皮部则不着色,呈阴性反应。可作为桑黄化型萎缩病病株的实验诊断手段。 相似文献
47.
[目的 ]构建重大动物疫病暴发流行预警指标体系。[方法 ]以禽流感和口蹄疫为例,采用文献调研法和德菲尔专家咨询法中的专家会议法初拟重大动物疫病预警体系的框架和指标;应用德菲尔专家咨询法评价预警指标的重要性、可操作性;应用组合权重法比较各指标综合影响的大小,并将指标分类。[结果 ]筛选出禽流感和口蹄疫预警预报一级指标6项(易感动物、饲养管理和免疫情况等)以及二级指标14项(免疫效果、环境消毒、温度等),并将指标分为三类(关键指标、重要指标和一般指标)。[结论 ]初步构建了重大动物疫病暴发流行预警指标体系。 相似文献
48.
49.
Weiguo?Cheng Wenxi?LuEmail author Xin?Xin Zheng?Zhang Haibo?Chu 《Paddy and Water Environment》2016,14(2):355-365
The existing irrigation schedule of most rice-growing areas in Jilin Province is not in full compliance with the Water Requirements Law of the rice; these discrepancies affect the yield of rice to some extent. Thus, research on rice water regulations and selection of an appropriate water production function model (WPFM) is very important. In this study, according to the water demand characteristics of rice, we used drought treatments separately during the tillering, jointing booting, flowering, and milky stages. Evapotranspiration and yield data were obtained using a test pit experiment and production measurements in 2011 and 2012, respectively. Five commonly used WPFMs (the Jensen, Blank, Minhas, Stewart, and Singh model) were selected for this study, and the water sensitivity index of each model was calculated based on the evapotranspiration, yield, and the model equations. The Jensen model was found to be the most suitable WPFM for this region; furthermore, a mathematical relationship between the water sensitivity index and days after rice planting was established. These results have important theoretical and practical implications for guidelines regarding rice irrigation in Jilin Province. 相似文献
50.
为了更好地指导养殖户和饲料生产企业进行生产,预防霉菌毒素,百奥明公司从全国各地收集各种饲料和原料样本,进行霉菌毒素检测,并形成季度报告。为行业内同仁提供参考。[第一段] 相似文献