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41.
为比较不同热处理条件对水牛乳稳定性的影响,实验采用不同条件热处理后的pH缓冲容量、总溶解固体(total dissolved solids,TDS)、蛋白沉淀量及表观黏度等指标研究杂交高代水牛乳样品。结果表明:与未经处理的水牛乳样品相比,水牛乳经不同条件热处理后,其pH缓冲容量、TDS、蛋白沉淀量及表观黏度皆发生显著变化。其中水牛乳分别在经121℃/15 min和95℃/5 min处理后,其pH缓冲容量、TDS、蛋白沉淀量及表观黏度分别达到最大值和最小值。因此,认为在本实验研究范围内,水牛乳经121℃/15 min及95℃/5 min处理后,对其稳定性影响最大。 相似文献
42.
本文采用一种新型绿色溶剂提取红枣总黄酮,并对其提取工艺进行优化.通过单因素试验探究含水量、超声功率、提取时间、提取温度和料液比对红枣总黄酮得率的影响.在此基础上,采用遗传算法优化超声辅助低共熔溶剂提取红枣总黄酮工艺.结果表明:超声辅助低共熔溶剂提取红枣总黄酮最优的工艺参数为:含水量37%、超声功率167 W、提取时间3... 相似文献
43.
去势术对雄性中华田园犬脂代谢的影响 《畜牧与饲料科学》2021,42(6):112-114
[目的] 研究去势术对雄性中华田园犬脂代谢的影响。[方法] 将12只年龄、体重相近的中华田园犬分为非手术组和去势组,对去势组中华田园犬进行去势手术,观察并测定术前第1天、术后第14天、术后第21天血清中甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白(LDL)、高密度脂蛋白(HDL)含量,以非手术组作为对照,分析去势术对雄性犬脂代谢的影响。[结果] 去势组与非手术组相比,血清中TG含量在第14天到第21天显著上升;血清中TC含量相比非手术组呈下降趋势;HDL第14天和第21天都低于非手术组;LDL都高于非手术组,整体呈上升趋势。[结论] 去势手术会影响雄性中华田园犬机体脂类代谢,会导致去势犬甘油三酯升高,总胆固醇和高密度脂蛋白下降,低密度脂蛋白上升。 相似文献
44.
试验旨在研究中草药复合微生态制剂(CHCP)对急性肝脏损伤蛋鸡肝脏的保护作用。试验分两部分:①用四氯化碳豆油(SCCl4)建立蛋鸡急性肝脏损伤模型。选取1 d健康蛋雏鸡108只随机分为4组,模型Ⅰ~Ⅲ组分别按1、2、4 mL/kg体重灌胃10%(V/V)SCCl4,对照组按2 mL/kg体重灌胃豆油,分别在14、28及35 d时各灌胃一次;②CHCP对蛋鸡急性肝脏损伤的影响。选择1 d 健康蛋雏鸡60只随机分为5组:对照组(豆油)、模型对照组(SCCl4)及低、中、高剂量CHCP组(SCCl4+1‰ CHCP、SCCl4+2‰ CHCP、SCCl4+4‰ CHCP),7 d起饮水使用CHCP,14、28 d按2 mL/kg体重剂量给鸡灌胃10% SCCl4。结果表明,按2 mL/kg体重剂量在14、28 d分别灌胃10% SCCl4即可造成蛋鸡肝脏损伤,引起肝细胞脂肪变性,空泡样变严重,核固缩,坏死;与模型对照组相比,低、中、高剂量CHCP组蛋鸡血清谷草转氨酶(AST)含量分别降低4.35%(P > 0.05)、7.57%(P > 0.05)及9.79%(P < 0.05),中、高剂量CHCP组血清谷丙转氨酶(ALT)含量分别降低34.92%(P < 0.01)、36.51%(P < 0.01),血清总胆红素(TB)含量分别降低25.49%(P < 0.01)、27.45%(P < 0.01);蛋鸡肝细胞切片显示CHCP不同剂量组肝细胞充血减轻,未见脂滴空泡,排列整齐,细胞质丰富而均匀。结果表明,本试验所用的CHCP按2‰、4‰饮水使用均能减少肉鸡肝细胞坏死,降低血清转氨酶活性及TB水平,对SCCl4诱导的肝脏损伤有保护作用。 相似文献
45.
贺兰山西坡不同海拔梯度草地土壤氮特征 总被引:9,自引:1,他引:9
以阿拉善左旗境内贺兰山中段(西坡)及山前地带不同海拔下的草地为研究对象,分析不同海拔梯度下草地土壤全氮的分布特征及其与气候因子、植被特征和土壤特性的关系.结果表明,土壤全氮含量随海拔的降低而逐渐降低,在典型草原中沿土壤垂直剖面依次降低,在高寒草甸、荒漠化草原和草原化荒漠0~20与20~40 cm土层中差异不显著,但高于40~60 cm土层.在海拔1 360~1 380 m草原化荒漠的5个样地上,由于放牧利用程度和植被类型的不同,0~20 cm土层土壤氮的含量变幅在0.022 8%~0.034 7%.0~20,20~40和40~60 cm土层土壤全氮含量与年降水量、植被盖度、草地生产力、土壤含水量、有机碳含量和<0.05 mm颗粒含量呈极显著正相关,与年均温、土壤pH值呈极显著负相关(P<0.001).偏相关分析显示,影响0~20 cm土层全氮(TN)含量最主要的因素是植被盖度(C)和年降水量(AP),相关方程是TN%=0.002 040 C 0.000 585 AP-0.076 800;而影响20~40 cm土层全氮含量的最主要因素是草地生产力(B),与土壤全氮回归方程为TN%=0.001 6 B 0.024 7.而各环境因素中影响土壤全氮含量最主要的因素,0~20 cm土层为土壤有机碳和年降水量,20~40 cm土层主要受土壤有机碳的影响. 相似文献
46.
四大药用菊花功能成分的比较研究 总被引:7,自引:1,他引:7
为了比较4种药用菊花的品质特征,采用比色法测定总黄酮含量,HPLC测定绿原酸含量,GC-MS分析挥发油的成分.结果表明,贡菊、滁菊、亳菊和杭菊中总黄酮的含量分别为5.608%、4.619%、4.372%和3.017%;绿原酸含量分别为0.345%、0.207%、0.337%和0.131%;挥发油总量分别为0.243%、0.524%、0.388%和0.212%;GC-MS分离鉴定出的化合物中贡菊有18种,滁菊有46种,亳菊有35种,杭菊有6种.可见贡菊的主要功能成分较其他3种菊花含量高,并且具有较好的香气品质,认为贡菊可能不仅更适合药用,同时适于作为饮料、功能和保健食品的原料. 相似文献
47.
磷、钾对番茄可溶性碳水化合物分配的影响 总被引:3,自引:0,他引:3
胡繁荣 《吉林农业大学学报》2004,26(2):151-154
以番茄苗为试验材料,研究了不同浓度磷、钾对番茄植株可溶性碳水化舍物分配的影响。结果表明:磷、钾亏缺处理45d后,与正常磷、钾处理相比,磷亏缺的植株冠根比下降,而钾亏缺的植株冠根比则上升。钾亏缺的植株叶片中,蔗糖、还原糖和总可溶性糖含量均表现为上升,根中则表现为下降。磷亏缺的植株叶片中,蔗糖、还原糖和总可溶性糖含量基本不变,而在根中则表现为不同程度的增加。在叶和根的总可溶性糖中,钾亏缺和磷亏缺的植株,根部总可溶性糖所占的比例分别为10.71%和45.65%,两者的对照分别为28.63%和33.11%。上述结果表明,钾和磷在光合产物的转运中所起的作用不同,植株中营养元素亏缺不同,干物质在不同部位的分配也不同。 相似文献
48.
Lucas Pellegrin Lilian Fiori Nitz Daniel de S Britto Pinto Carlos Eduardo Copatti Wilson Wasielesky Luciano Garcia 《Aquaculture Research》2022,53(1):276-284
This study determined the effects of total suspended solids (TSS) on pacu (Piaractus mesopotamicus) culture in a biofloc technology (BFT) system by performing two experiments. Experiment 1 evaluated the LC50-96 h of pacu at seven TSS levels (0, 1500, 3000, 4000, 5000, 6000 and 7000 mg L?1). Experiment 2 evaluated haematological variables (glucose, pH, haematocrit, haemoglobin, erythrocytes and haematimetric indices) in juveniles exposed to five different sublethal TSS concentrations (0, 250, 500, 750 and 1000 mg L?1) for 5 days. Treatments below 5000 mg L?1 did not cause mortality, and the LC50-96 h of TSS was estimated at 5477 mg L?1. The TSS concentrations that caused mortality in pacu juveniles were extremely high and rarely maintained in culture systems. Exposure to high TSS concentrations (mainly 750 and 1000 mg L?1) increased blood glucose, pH, heamatocrit, erythrocytes, haemoglobin values and haematimetric indices on the first day. On the fifth day, most of the evaluated parameters stabilized at different TSS concentrations. In conclusion, pacu exposed to high TSS concentrations for short periods may undergo physiological changes, and TSS concentrations below 250 mg L?1 are recommended for its culture in a BFT system. 相似文献
49.
Mannarino R Luna SP Monteiro ER Beier SL Castro VB 《Veterinary anaesthesia and analgesia》2012,39(2):160-173
ObjectiveTo evaluate the effects of a constant rate infusion (CRI) of lidocaine alone or in combination with ketamine on the minimum infusion rate (MIR) of propofol in dogs and to compare the hemodynamic effects produced by propofol, propofol-lidocaine or propofol-lidocaine-ketamine anesthesia.Study designProspective, randomized cross-over experimental design.AnimalsFourteen adult mixed-breed dogs weighing 15.8 ± 3.5 kg.MethodsEight dogs were anesthetized on different occasions to determine the MIR of propofol alone and propofol in combination with lidocaine (loading dose [LD] 1.5 mg kg?1, CRI 0.25 mg kg?1 minute?1) or lidocaine (LD 1.5 mg kg?1, CRI 0.25 mg kg?1 minute?1) and ketamine (LD 1 mg kg?1, CRI 0.1 mg kg?1 minute?1). In six other dogs, the hemodynamic effects and bispectral index (BIS) were investigated. Each animal received each treatment (propofol, propofol-lidocaine or propofol-lidocaine-ketamine) on the basis of the MIR of propofol determined in the first set of experiments.ResultsMean ± SD MIR of propofol was 0.51 ± 0.08 mg kg?1 minute?1. Lidocaine-ketamine significantly decreased the MIR of propofol to 0.31 ± 0.07 mg kg?1 minute?1 (37 ± 18% reduction), although lidocaine alone did not (0.42 ± 0.08 mg kg?1 minute?1, 18 ± 7% reduction). Hemodynamic effects were similar in all treatments. Compared with the conscious state, in all treatments, heart rate, cardiac index, mean arterial blood pressure, stroke index and oxygen delivery index decreased significantly, whereas systemic vascular resistance index increased. Stroke index was lower in dogs treated with propofol-lidocaine-ketamine at 30 minutes compared with propofol alone. The BIS was lower during anesthesia with propofol-lidocaine-ketamine compared to propofol alone.Conclusions and clinical relevanceLidocaine-ketamine, but not lidocaine alone, reduced the MIR of propofol in dogs. Neither lidocaine nor lidocaine in combination with ketamine attenuated cardiovascular depression produced by a continuous rate infusion of propofol. 相似文献
50.
Intravenous sufentanil‐midazolam versus sevoflurane anaesthesia in medetomidine pre‐medicated Himalayan rabbits undergoing ovariohysterectomy 下载免费PDF全文
Patricia Hedenqvist Marianne Jensen‐Waern Åsa Fahlman Ragnvi Hagman Anna Edner 《Veterinary anaesthesia and analgesia》2015,42(4):377-385
ObjectiveTo compare physiological effects of sufentanil-midazolam with sevoflurane for surgical anaesthesia in medetomidine premedicated rabbits.Study designProspective, randomized controlled experimental study.AnimalsEighteen female Himalayan rabbits, weight 2.1 ± 0.1 kg.MethodsPremedication with 0.1 mg kg−1 medetomidine and 5 mg kg−1 carprofen subcutaneously, was followed by intravenous anaesthetic induction with sufentanil (2.3 μg mL−1) and midazolam (0.45 mg mL−1). After endotracheal intubation, anaesthesia was maintained with sufentanil-midazolam (n = 9) or sevoflurane (n = 9). Ovariohysterectomy was performed. Intermittent positive pressure ventilation was performed as required. Physiological variables were studied perioperatively. Group means of physiologic data were generated for different anaesthetic periods. Data were compared for changes from sedation, and between groups by anova. Post-operatively, 0.05 mg kg−1 buprenorphine was administered once and 5 mg kg−1 carprofen once daily for 2–3 days. Rabbits were examined and weighed daily until one week after surgery.ResultsSmooth induction of anaesthesia was achieved within 5 minutes. Sufentanil and midazolam doses were 0.5 μg kg−1 and 0.1 mg kg−1, during induction and 3.9 μg kg−1 hour−1 and 0.8 mg kg−1 hour−1 during surgery, respectively. End-tidal sevoflurane concentration was 2.1% during surgery. Assisted ventilation was required in nine rabbits receiving sufentanil-midazolam and four receiving sevoflurane. There were no differences between groups in physiologic data other than arterial carbon dioxide. In rabbits receiving sevoflurane, mean arterial pressure decreased pre-surgical intervention, heart rate increased 25% during and after surgery and body weight decreased 4% post-operatively. Post-operative problems sometimes resulted from catheterization of the ear artery.ConclusionSevoflurane and sufentanil-midazolam provided surgical anaesthesia of similar quality. Arterial blood pressure was sustained during sufentanil-midazolam anaesthesia and rabbits receiving sevoflurane lost body weight following ovariohysterectomy. Mechanical ventilation was required with both anaesthetic regimens.Clinical relevanceAnaesthesia with sufentanil-midazolam in medetomidine premedicated healthy rabbits is useful in the clinical and the research setting, as an alternative to sevoflurane. 相似文献