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为寻找一种能够科学高效地将小站稻秸秆用于秸秆还田的方法,并将其作为一种储备技术,本研究通过测定已有6组秸秆降解复合菌系的羧甲基纤维素酶活力和滤纸酶活力,筛选出2组复合菌系,并通过正交试验进行产酶条件的优化,以探索解决小站稻秸秆清洁生产技术的应用问题,保障小站稻的未来绿色可持续发展,为小站稻秸秆高效处理的研究提供理论基础和技术支持。本研究结果表明:复合菌系B和复合菌系F的综合酶活力均高于其他复合菌系;复合菌系B羧甲基纤维素酶最佳发酵条件为25℃,pH 8.0,接种量2%,温度为酶活力主要影响因素;复合菌系B滤纸酶最佳发酵条件为20℃,pH 9.0,接种量2%,pH为酶活力主要影响因素;复合菌系F羧甲基纤维素酶最佳发酵条件为25℃,pH 8.0,接种量2%,温度为酶活力主要影响因素;复合菌系F滤纸酶最佳发酵条件为20℃,pH9.0,接种量2%,接种量为酶活力主要影响因素。 相似文献
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拟康氏木霉固态发酵产纤维素酶系的研究 总被引:1,自引:0,他引:1
以稻草秸秆为主要原料,利用拟康氏木霉3.3002(Trichoderma pseudokoningii 3.3002)固态发酵生产纤维素酶,对培养条件进行了优化,并系统地测定了各种纤维素酶的酶活.结果表明,最优产酶培养基组成为:稻草秸秆和麸皮的混合比例为4:1,最佳氮源为2.5%(NH4)2SO4,最佳发酵时间120 h,培养温度35℃,接种量15%,pH 5.0,培养基含水率50%.在此条件下,该菌株产纤维素酶系中羧甲基纤维素酶(Cx)酶活力达4700 U/mL,葡聚糖外切酶(Cb)酶活力达3440 U/mL,葡萄糖内切酶(C1)酶活力达到1620 U/mL,滤纸酶(FPA)酶活力达到1935 U/mL. 相似文献
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酶解蚕蛹蛋白制备血管紧张素转换酶抑制肽的工艺优化 总被引:2,自引:0,他引:2
采用碱性蛋白酶水解蚕蛹蛋白,制备血管紧张素转换酶(angiotensin-converting enzyme,ACE)抑制肽,是蚕蛹蛋白深度开发的途径之一。以ACE抑制率为响应值,用响应面分析法研究酶解温度、酶解pH和加酶量等因素对酶解产物的ACE抑制活性的影响,优化制备工艺。结果表明,各因素对制备ACE抑制肽的活性影响程度由大到小依次为酶解pH、酶解温度、加酶量。获得碱性蛋白酶水解蚕蛹蛋白制备ACE抑制肽的最佳工艺条件为:酶解温度50.8℃,酶解pH 9.0,加酶量3 500 U/g。在此条件下,蚕蛹蛋白酶解产物对ACE的理论抑制率最高可达96.67%,验证值为96.49%±1.75%,IC50值为0.102 mg/mL,预测模型可靠性高,可应用于蚕蛹ACE抑制肽的酶法制备。 相似文献
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复合酶法提取松针粉挥发油的研究 总被引:7,自引:0,他引:7
本试验主要研究利用复合酶提取松针粉的有效成分挥发油,以建立一套行之有效的使用复合酶提取中草药方法,为推广应用复合酶法在提取中草药生产上提供理论依据.试验分为三部分,即常规蒸馏提取试验、单因子试验、多因子试验.其中单因子试验从酶解温度、酶解作用时间、pH、加酶量4个因素考察酶解对松针粉挥发油提取量的影响,多因子试验采用4因素(pH、酶解温度、酶解作用时间、加酶量)三水平做正交试验,确定复合酶法提取松针粉的最佳反应条件.由正交试验得出最佳酶解反应条件是:酶解温度为50℃,pH值为4.5,酶解时间为6h,加酶量为4%.最后对加酶和未加酶组进行t检验比较,结果显示复合酶法提取松针粉有效成分挥发油比常规的提取量高出37.9%,两种方法差异极显著,有效地证明了复合酶可以加大松针粉有效成分的提取量. 相似文献
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试验旨在探究油菜秸秆最佳的预处理工艺及其发酵产酶的效果。在油菜秸秆粉末预处理中,以秸秆保留量、预处理秸秆酶解产糖量、初始秸秆比产糖量为预处理的评估指标,考察浸泡时间、处理液浓度、液料比、处理液、秸秆粉碎程度等5个因素对预处理后秸秆粉末的影响,通过正交试验确定出最佳预处理工艺,以浸泡温度、浸泡时间、处理液浓度作为考察因素。结果显示:通过单因素和正交试验优化得到最佳预处理的条件为以40~60目的油菜秸秆粉为原料,液料比10 mL/g,温度45℃,在1.1%的NaOH中浸泡36 h。在最优条件下,秸秆比产糖量达0.181 1 g/g。在固态产酶优化试验中考察碳源配比、氮源浓度、液料比、接种量、培养温度、培养时间等6个因素对固态发酵产酶优化的影响,通过正交试验确定出最佳固态发酵产酶优化条件,以碳源配比、氮源浓度、培养温度、培养时间作为考察因素。通过单因素和正交试验优化,得到最佳发酵条件为油菜秸秆粉和麸皮比为5∶4、硫酸铵浓度为2.5%、液料比1.5 mL/g、接种量5%、培养温度30℃、培养时间5 d,产纤维素酶活提高至7.923 IU。研究表明,通过对油菜秸秆进行预处理及产酶发酵后,能够显著... 相似文献
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Rassnick KM Gieger TL Williams LE Ruslander DM Northrup NC Kristal O Myers NC Moore AS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2001,15(3):196-199
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks. 相似文献
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Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects 总被引:1,自引:0,他引:1
Johansson AM Gardner SY Levine JF Papich MG LaFevers DH Fuquay LR Reagan VH Atkins CE 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(6):887-895
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses. 相似文献
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Waruiru RM Thamsborg SM Nansen P Kyvsgaard NC Bogh HO Munyua WK Gathuma JM 《Tropical animal health and production》2001,33(3):173-187
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round. 相似文献
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The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host. 相似文献
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Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ
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S. Pashaei T. Ghoorchi A. Yamchi 《Journal of animal physiology and animal nutrition》2016,100(2):211-216
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed. 相似文献
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Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb
albumin
- ALT
alanine aminotransferase
- AST
aspartate aminotransferase
- BUN
blood urea nitrogen
- Chol
cholesterol
- Glob
globulin
- -GT
-glutamyl transpeptidase
- IP
inorganic phosphorus
- TP
total protein 相似文献
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A knowledge of the microbiological status of milk and of the different structures in the mammary glands has great importance
in elucidating the pathogenesis of mammary gland infections. The objective of this study was to evaluate the microbiological
status of various structures in the mammary glands from naturally infected dairy cows following slaughter. A total of 94 samples
of milk, 184 samples of mammary parenchyma, 168 samples of gland cisterns, and 168 samples of teat cisterns were collected
for microbiological examination. Microorganisms were detected in 59.9% of all samples, 67.0% of the milk samples, 70.1% of
the mammary parenchymas, 55.9% of the gland cisterns and 48.8% of the teat cistern samples. When all samples were considered,
coagulase-negative Staphylococcus were the most prevalent (35.7%) followed by coagulase-positive Staphylococcus (12.2%), Corynebacterium bovis (2.4%), Prototheca sp. (1.9%), and Streptococcus dysgalactiae (1.5%). There was a significantly higher occurrence of microorganisms in the milk and mammary parenchyma compared to the
gland cisterns and teat cisterns.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Four grass plots were sequentially contaminated with goat faeces containing known numbers of unembryonated eggs of predominantly Haemonchus contortus and Trichostrongylus spp. between October 1982 and April 1983. Four other plots were similarly contaminated with sheep faeces between February and May 1987. An additional plot was repeatedly contaminated with sheep faeces from February to April 1987. Populations of free-living stages in faeces and of infective larvae (L3) in the herbage were subsequently monitored until the end of April and June of 1983 and 1987 respectively. During February and May 1987 two control cultures of sheep faeces were incubated in the laboratory at 25°C–30°C and at a constant temperature of 50°C and the free-living development was also monitored. L3 developed very readily in the faeces cultured at 25°C–30°C and in those spread on a grass plot in October, at the end of the wet season, but developed less on the plot contaminated in May at the start of the wet season. Worm eggs in faeces deposited on plots during the hot dry season (December to April) or incubated at 50°C died and disintegrated after 24–48 h exposure to the high environmental temperatures. The results indicate that it is unlikely that gastrointestinal nematodes of sheep and goats can develop or survive on open pasture during the dry season in the Nigerian derived savanna zone. 相似文献
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Acute phase proteins in dogs naturally infected with the Giant Kidney Worm (Dioctophyme renale)
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Elizabeth M. S. Schmidt Mads Kjelgaard‐Hansen Funmilola Thomas Asta Tvarijonaviciute José J. Cerón P. David Eckersall 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2016,45(4):657-664