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1.
家蚕RAPD的扩增条件、重复性及遗传模型研究   总被引:36,自引:15,他引:21  
发现当PCR体系中Mg ̄(2+)为2mmol/L、dNTPs为150μmol/L、Tag酶为1U、引物为0.2μmol/L时,以40~42℃退火可得到稳定结果;8%的DMSO对提高扩增特异性有利;分别从蚕卵、蚁蚕、5龄蚕丝腺、体壁及生殖腺、蛹、蛾中提取模板DNA,其RAPD结果一致;以C_(108)×大造为材料,发现其F_1RAPD为共显性。  相似文献   

2.
采用超速离心、热变性处理、硫酸铵沉淀和亲和层析方法,从鸡肝脏中分离提纯了β-羟-β-甲戊二酸单酰辅酶A(HMG-CoA)还原酶。提纯倍数为209倍,比活力188.5U/mg,Km值1.8×10-4mol/L。SDS-PAGE测得分子量为3.2×104。温度对该酶活性影响较大,37℃时活性最高。最适反应pH为7.2。甘氨酸在10mmol/L浓度以上时对该酶呈现明显抑制作用,l-组氨酸、l-精氨酸则无明显抑制作用。Zn2+、Mg2+、Cu2+离子对该酶有明显抑制作用,Zn2+在1.5mmol/L、Cu2+和Mg2+在2.0mmol/L浓度以上时抑制作用明显。中药山楂(CHS)和决明子(CHZ)的水煎液对酶的抑制作用明显  相似文献   

3.
利用3株特异性单抗,建立了检测EDSV的夹心ELISA方法。经测定,McAb最适包被浓度为2μg/ml,McAb-HRP最佳工作浓度为1∶400,该方法最小检出浓度为0.03μg/ml,与常见的几种鸡的传染病的病原无交叉反应。对某发病鸡场的50份泄殖腔拭子样本进行了检测,阳性率为84%(42/50)。  相似文献   

4.
微分脉冲催化极谱法测定乳牛全血硒   总被引:1,自引:0,他引:1  
采用美国273A型电化学分析系统,根据SeSO32--KIO3氧化还原反应原理,用微分脉冲催化极谱法测定了奶牛全血痕量硒。此法最低检出极限0.1μg/L,线性范围0.5~5.0μg/L,回收率92.60%~103.00%。硒标准溶液和饲料重复测定值的变异系数分别为1.5%和2.2%。奶牛全血硒的测定值符合饲料梯度添加试验,其精密度和准确度均高。  相似文献   

5.
山羊卵巢无腔卵泡卵母细胞的体外生长   总被引:6,自引:0,他引:6  
山羊卵巢无腔卵泡卵母细胞在以DMEM为基础,添加HEPES(20mmol/L)、FCS(10%)、FSH(40mg/L)、次黄嘌呤(2mmol/L)、异双丁酰环腺苷酸(2mmol/L)、IGF-I(50μg/L)、氢化可的松(40μg/L)和ITS(50μg/L)的培养液中得以存活并生长。在二维培养体系中,卵泡在体外的生长模式和体内有很大差别。最显著的特征是卵泡不像在体内那样保持完整的立体结构一直到结束。绝大部分卵泡不同程度地发生基膜溶解和破裂,颗粒细胞向四周扩展并贴壁,形成单层。由于卵泡原有三维立体结构的破坏,易于导致卵母细胞的迁移。在生长方式上以数个卵泡聚集生长对其卵母细胞的生长似乎较为有利。卵泡卵母细胞在体外培养9d,其直径可达150μm以上,达到了成熟时体积,存活率为53%。实验证明,山羊无腔卵泡卵母细胞在合适的培养体系中,能在体外存活并生长,并能发育到成熟时的大小。  相似文献   

6.
猪核移植重组胚胎的发育能力   总被引:1,自引:0,他引:1  
以McGrath-Solter(1983)提供的去(注)核方法,将猪胚胎的单个卵裂球细胞注入去核的次级成熟卵母细胞,借助电融合的方法(AC;5V,1.5MHz,12-15s;DC:2kV/cm,40μs。电激活/融合液:0.3mol/L甘露醇+-.1mmol/LMgSO4+0.1mmolCacL2+7.5mg/mlCCB)融入受体胞质构成重级胚,体外培养(培养液为改衣TCM-199;培养条件为5%  相似文献   

7.
应用原子吸收光谱测定蜂蜜中铁的研究   总被引:1,自引:0,他引:1  
本实验利用火焰原子吸收法测定蜂蜜中的铁。测量波长248.3nm,狭缝0.2nm,灯电流5.0mA,空气流量10.0L/min,乙炔流量2.00L/min。样品经消解或灰化(550℃)等处理后导入火焰测定吸光度,与标准系列比较定量。测得蜂蜜样品中铁含量为40.3μg/ml,RSD%=1.29,回收率=100.4%。  相似文献   

8.
采用试管二倍稀释法,测定FQS312、FQS313、FQS314、FQS714对16株细菌的最小抑(杀)菌浓度,结果显示:FQS312、FQS313、FQS314对革兰氏阴性菌及阳性菌具有较强的抑菌活性。其中对乳房炎链球菌的抗菌活性最强,MIC分别为1.68μg/ml、1.84μg/ml、2.71μg/ml,MBC分别为6.72μg/ml、6.56μg/ml、6.82μg/ml。  相似文献   

9.
本研究根据伪狂犬病病毒(PrV)共有gB和疫苗株缺失的gE基因序列分别设计合成1对通用(PB1/PB2)和1对鉴别引物(PE1/PE2),以在我国广泛使用的疫苗株Bartha-K61及从国内外收集的野毒株S、SU、F、L、Y、Min-A、Shope、S(川)、SL1、10#、EA(鄂A)DNA为模板在同一反应管中同时扩增gB和gE基因序列建立了复合多聚酶链反应(PCR)方法。PCR产物经2.0%琼  相似文献   

10.
假俭草侧芽愈伤诱导和植株再生   总被引:3,自引:3,他引:0  
以中国优良品系E 126假俭草的侧芽为外植体建立高效的再生体系。试验结果显示,1)适宜于侧芽生长的培养基为MS+BAP2.0mg/L+NAA0.8 mg/L;2)在最佳诱导培养基MS+2,4 D1.0 mg/L+BAP0.1 mg/L上,侧芽愈伤诱导率达93%。较强的光照能提高愈伤组织的诱导率;3)在最佳分化培养基MS+KT2.0mg/L 上,绿苗分化率为12.6%;4)试管苗最佳生长培养基为MS+BAP2.0mg/L+NAA0.8 mg/L;5)在最佳生根培养基MS+NAA0.6mg/L 上,试管苗的生根率达98%,植株移栽成活率为94%。本试验为假俭草体细胞筛选和遗传转化提供依据。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
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   

13.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

14.
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.  相似文献   

15.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   

16.
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   

17.
18.
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   

19.
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   

20.
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