均匀设计法优化金银花水煎液絮凝提取工艺的研究

用均匀设计法优化金银花水煎液絮凝提取工艺。考察了絮凝剂浓度、絮凝时间、pH、温度4个因素对金银花水煎液提取率的影响，得到金银花水煎液絮凝提取工艺的优化条件为絮凝剂浓度2．0％、絮凝时间20min、pH5．0、温度50℃，并对絮凝后的金银花水煎液进行了絮凝效果检验。此工艺较好地去除了蛋白质、鞣质、淀粉等杂质，保留了有效成分绿原酸。选用絮凝法提取效果好，安全度高，可替代传统水提醇沉法。     

Box-Behnken响应面法优化红芪多糖水提醇沉工艺研究

优化红芪多糖标准提取物的水提醇沉制备工艺参数。采用L₉(3~4)正交试验优选红芪总糖水提工艺，采用Box-Behnken中心组合响应面法优化红芪多糖醇沉工艺，以“化学-生物活性”综合指标进行评价。结果表明，优化得到的红芪多糖水提醇沉制备工艺为：原料药材加水10倍量(首次12倍量),煎煮3次，每次1 h,合并药液，浓缩至与原料药材1∶1,进行醇沉，醇沉浓度77%,醇沉时间10 h,醇沉次数3次。按上述醇沉工艺所得提取物中多糖质量分数为60.52%,相比原药材水提取物中多糖质量分数的23.2%,纯度提高了1.61倍，且工艺稳定；所得提取物具有较好的抗氧化活性及DPPH自由基清除活性。说明该工艺可用于红芪多糖标准提取物的制备及开发利用。     

甘肃沙枣多糖提取工艺研究

采用热水浸提、醇沉法提取沙枣多糖,对沙枣多糖提取工艺进行了研究。选择料液比、浸提温度和浸提时间作为单因素进行梯度实验,确定其提取备件范围,再通过正交试验进一步确定沙枣多糖最佳提取工艺条件。结果表明,沙枣多糖的最佳提取工艺为：浸提温度为85℃、固液比为1：60、浸提时间为2h,在此条件下提取得甘肃沙枣多糖含量为4．98％。     

兽用黄芪多糖口服液提取工艺研究

为建立黄芪中黄芪多糖提取工艺,本研究采用单因素试验和正交试验相结合的方法,以黄芪多糖为指标,对发酵浓度、发酵时间、发酵pH、发酵温度、醇沉提取时间进行优化。结果表明,6%的接种浓度、pH为7、温度控制在36℃、培养24 h、醇沉提取时间60 min,为黄芪多糖最佳提取工艺。经验证,该工艺方法简单,较传统提取法能耗小、成本低、安全环保、重复性好,能够用于工业化生产。     

不同方法处理的金银花提取液在鸡胚内抗新城疫病毒作用

水提醇沉法是传统的中药澄清分离法,但是水提醇沉法有耗时、成本高、有污染及存在乙醇残留等缺点.因此又提出了高速离心法、壳聚糖絮凝澄清法等新方法[1-2].高速离心法和壳聚糖絮凝澄清法具有省时、成本低、无污染及无药物残留等优点.但是这两种方法对中药提取液中有效成分是否有影响,对中药提取液在动物机体内的抗病毒效果如何,还未见有报道.本试验以金银花提取液为例,通过比较高速离心法、壳聚糖絮凝澄清法与水提醇沉法三种方法处理的金银花提取液在鸡胚内抗新城疫病毒作用研究,探讨3种中药澄清分离方法的优劣,为今后进行中药鸡胚抗病毒试验以及选择更合适的中药提取液的澄清分离方法提供科学的理论依据.     

壳聚糖絮凝对双黄连口服液制剂中有效成分的影响

选用正交试验筛选壳聚糖絮凝澄清的最佳条件,以主要成分黄芩苷作为含量考察指标,研究了壳聚糖作为澄清剂对双黄连口服液中黄芩苷含量的影响,并与醇沉法进行了对比。结果显示,壳聚糖能使双黄连提取液得到良好的澄清效果,主要成分黄芩苷损失较小,优于醇沉法,表明壳聚糖能作为良好的澄清剂代替醇沉法处理双黄连口服液。     

响应面法优化双黄连口服液醇沉物乳酸菌发酵工艺

为研究双黄连口服液制剂醇沉物的乳酸菌液态发酵工艺,首先确定双黄连口服液制剂醇沉物添加量,再以活菌数作为指标,通过单因素试验分别研究接种量、发酵时间和发酵温度的影响,并采用响应面法优选最佳发酵条件,最后进行平行放大试验验证。结果：含20%的醇沉物、接种量4%、发酵温度32.7℃、发酵时间26 h时活菌数可达3.03×10⁹ CFU/mL,为最佳发酵条件。平行放大验证试验表明,该发酵工艺可用于制备双黄连口服液醇沉物乳酸菌液态发酵制剂。     

苦参碱的提取纯化工艺研究

为了优化苦参碱的提取工艺,以浸膏收率、苦参碱含量为评价指标,选择用水量、提取时间及提取次数为考察因素,利用L9（3^4）正交试验法优选出水煎煮法提取苦参碱的最佳工艺条件为用8倍量水提取3次,每次提取2h。采用乙醇沉淀及三氯甲烷萃取相结合的方法对苦参粗提物进行纯化,浓缩药液浓度为1．0g生药／mL时进行醇沉,醇沉后调节药液的pH值至9～11用三氯甲烷萃取3次。优选出的提取工艺稳定、可行,可用于苦参碱的工业化提取。     

苦参碱的提取纯化工艺研究

为了优化苦参碱的提取工艺,以浸膏收率、苦参总碱含量为评价指标,选择用水量、提取时间及提取次数为考察因素,利用L9（3^4）正交试验法优选出水煎煮法提取苦参总碱的最佳工艺条件为用8倍量水提取3次,每次提取2h,并采用乙醇沉淀及三氯甲烷萃取相结合的方法对苦参粗提物进行纯化,浓缩药液浓度为每毫升1．0g生药时进行醇沉,醇沉后调节药液的pH值至9-11用三氯甲烷萃取3次。优选出的提取工艺稳定、合理、可行。     

壳聚糖纯化黄芩黄酮工艺研究

目的：确定壳聚糖对黄芩黄酮浸提液纯化的优化工艺条件。方法：通过正交试验设计考察壳聚糖添加量、料液温度和pH值对黄芩黄酮浸提液纯化效果。结论：壳聚糖对黄芩黄酮浸提液具有较好的纯化作用,最佳工艺条件为A3B2C2,即药液温度50℃、壳聚糖加入量为2%、pH值为5。     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

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.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

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.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

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.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

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.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

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.     

Serum biochemical values and mineral element contents of tissues in yaks

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