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1.
Chronological ages have been assigned to the defassa waterbuck of western Uganda using four complementary techniques. These are the "jaw board" method in which collected skulls are sorted into arbitrary groups based upon tooth eruption and attrition; tooth impressions taken from immobilised animals at yearly intervals; counting of cementum lines in sectioned incisor teeth, and growth of horns in young males. Using these methods an animal could be aged to within plus or minus six months.  相似文献   

2.
Two drug combinations were tested during 18 field captures of 14 individual impala in northern Kenya in 1966–67. Nine additional impala, eight females and one male, were darted but not captured. Dosages of 0.45 mg M.99+10.0 mg acepromazine+4.5 mg hyoscine were adequate for males, but did not completely immobilize them. Females proved more difficult to capture, and all attempts using the acepromazine mixture were unsuccessful. The substitution of phencyclidine for acepromazine, and the deletion of hyoscine, proved a more suitable mixture. A dosage of 0.32 mg M.99+90 mg phencyclidine per animal completely immobilized both sexes. The phencyclidine-M.99 mixture was judged an improvement over other common field immobilizing drugs, but the long recovery time limits the usefulness of this drug combination for large-scale capturing operations.  相似文献   

3.
Black rhinoceroses were hunted on foot, from a vehicle, or from a helicopter throughout their range of habitats. Animals weighing 370–1,260 kg could be handled an average of 13 min after darting with a mixture of etorphine (1.9 μg/kg) and acepromazine (19 μg/kg). Cases of respiratory depression at this dosage were reversed soon after immobilisation by the intravenous injection of cyprenorphine (1.0 μg/kg). The captured animal was transported to camp, lashed on its side to a sledge, for periods of up to 515 min without mishap. A rhinoceros that was unloaded 180 min after darting rose to its feet and tried to push its way through the corner of the pen until antidote was administered at 215 min. This action was not observed in animals that received a total dose of 3.4 μg/kg of cyprenorphine before being unloaded 90–413 min after darting. The addition of hyoscine (at doses as low as 18 μg/kg) to etorphine and acepromazine improved the tractability of rhinoceroses that were only partially immobilised. However, sometimes at this dosage and always at doses above 35 μg/kg, hyoscine prolonged the ‘pushing’ phase for 175–410 min after darting despite the administration of cyprenorphine (4.0 μg/kg). There were no mortalities due to drug action in the series of 59 healthy rhinoceroses that were dart-immobilised, but there were two deaths due to mishandling and one caused by subsequent mismanagement.  相似文献   

4.
人工养殖与选育对罗氏沼虾遗传多样性的影响   总被引:3,自引:0,他引:3  
为探讨人工养殖与选择育种对罗氏沼虾(Macrobrachium rosenbergii)遗传多样性的影响,实验测定了孟加拉野生群体、缅甸野生群体、浙江养殖群体、广西养殖群体及选育群体"南太湖2号"共111只罗氏沼虾核糖体转录间隔区2(Internal transcribed spacer 2,ITS2)基因序列,结果发现58个碱基变异位点,定义56个单倍型。在5个群体中,孟加拉野生群体的遗传多样性最高(平均核苷酸差异数K和核苷酸多态性指数Pi分别为7.186和0.0155),依次为缅甸野生群体、浙江养殖群体、广西养殖群体,选育群体"南太湖2号"遗传多样性最低(K和Pi分别为3.032和0.0065)。5个群体间配对Fst分析表明,养殖群体与野生群体遗传分化显著(P<0.01),选育群体"南太湖2号"不仅与野生群体遗传分化显著,同时还与广西养殖群体产生了显著的遗传分化(P<0.01)。系统树显示,孟加拉野生群体和缅甸野生群体聚为一支,浙江养殖群体、广西养殖群体和选育群体"南太湖2号"则聚为另一支。研究结果表明,人工养殖和选育降低了罗氏沼虾的遗传多样性水平,并导致群体间发生了显著的遗传分化。  相似文献   

5.
Waterbuck activity was recorded at four-minute intervals for continuous periods of 12 hours on two or three consecutive days, and for single nocturnal periods. Feeding patterns of the male and female were similar and during the day there was no hour during which some feeding did not take place. Only male activity was recorded at night. This showed more intensive feeding but with periods of no feeding just after dark and just before dawn. The use of a four-minute recording interval was found to work well in practice.  相似文献   

6.
The waterbuck (Kobus ellipsiprymnus), though widespread throughout Africa, is suspected to be declining overall. Data on population numbers and structure are lacking for many parts of its range, especially in West Africa, where the subspecies defassa is found. The aim of the present study was to evaluate the abundance, distribution and attributes of waterbuck populations from the Nazinga Forest Reserve, southern Burkina Faso. We investigated waterbuck population trends in the park using transect data collected in 1985–2019. For the more detailed analyses of population structure and distribution of the animals, we used census data gathered during 2019. Most animals were adults (46.6%), and the sex ratio was heavily skewed towards females (5:1). Most animals were concentrated along the larger rivers. There was no influence of poacher activity on waterbuck distribution. In the long term (1985–2019), the population dynamics of waterbuck can be roughly divided into two main periods: a phase of population increase from 1985 to 2005, and one of ongoing population collapse from 2007 to 2019. Although the declining population trend was obvious, coefficients of determination were low indicating that the years explained poorly the number of individuals and the number of sightings obtained. Waterbuck numbers in the Nazinga Forest Reserve are declining, but we found no single reason to explain this trend. It is likely that a combination of factors, including global warming (increased aridity) and illegal activities such as poaching, is responsible. Because there are probably multiple reasons for the observed waterbuck population decline in our study area, we suggest that a multifaceted approach should be adopted in order to enhance the conservation status of the local waterbuck populations.  相似文献   

7.
旱前胡的化学成分   总被引:2,自引:0,他引:2  
从云南产早前胡(Ligusticum daucoides Franch.)(伞形科)根的脂溶性部分分离了11个化合物,分别为香豆素化合物:columbianadin,isoedultin,archangelicin,旱前胡甲素(daucoidin A),旱前胡乙素(dsucoidin B),佛手柑内酯(bergapten),非香豆素化合物:falcarindiol(7),阿魏酸(ferulic acid),蜡酸(cerotic acid),β-谷甾醇(β-sitosterol),胡萝卜甙(daucosterol)。其中,化合物4和5是新的香豆素化合物,经化学方法及光谱测定,证明其结构为:4是3′去乙酰基isoedultin,即:2′(S)-(1″,1″-二甲基,1″-当归酰氧基)-3′(R)-羟基-角型二氢呋喃香豆素[2′(S)-(1″,1″-dimethvl,1″-angelovloxv)—3′(R)-hydroxy angular dihydrofuranocoumarin];5是2′-(1″-甲基,1″-羟基,1″-当归酰氧亚甲基)-角型二氢呋喃香豆素[2′-(1″-methyl,1″-hydroXy,1″-angeloyloxy-methylene)angular dihydrofuranocoumarin]。  相似文献   

8.
Poly(ethylene) hollow-fibre membranes with immobilised Cibacron Blue F3G-A were obtained in four different ways from epoxy-activated fibres. Membranes with a maximum capacity of 26 mg lysozyme ml–1and a dye density of 52 mol ml–1were obtained when ammonia was used to open the epoxy group before dye immobilisation. Pure water flux of the modified membranes at 1 bar pressure was 1.0 cm min–1, thus meaning only a reduction of 1.5-fold with regard to the unmodified membranes. The support-dye bond was stable as judged by the unmodified capacity of the membranes and the negligible amount of dye leaked after 520 h of exposure to 6 M urea in 0.5 M NaOH.  相似文献   

9.
10.
Parenteral anesthetic combinations such as ketamine and xylazine have become the agents of choice for anesthesia in the rabbit, because they are effective, easily administered and inexpensive. A number of recent reports have recommended including acepromazine in this combination, but a critical evaluation of this combination in the rabbit has not been reported. Five adult New Zealand white rabbits were anesthetized intramuscularly with ketamine (35 mg/kg) and xylazine (5 mg/kg) with or without acepromazine (0.75 mg/kg). The study was conducted in a double blind fashion, where each rabbit was administered both combinations at a minimum of 7 day intervals. Physiologic parameters were evaluated including heart rate, respiratory rate, central arterial blood pressure, pedal, palpebral and postural reflex activity. The duration of general anesthesia, estimated by the time elapsed between the loss and return of the palpebral reflex, was greater (means = 99 +/- 20 minutes) when acepromazine was employed in the combination compared to (means = 77 +/- 5 minutes) when ketamine/xylazine were used alone. Mean central arterial blood pressure reached a lower level when acepromazine was utilized (means = 46 +/- 8 mm/Hg) than when it was not (means = 57 +/- 12 mm/Hg.). The addition of acepromazine in a ketamine/xylazine combination resulted in a 28% longer period of anesthesia, a 19% lower mean central arterial blood pressure and a 32% longer recovery of postural reflexes. The ketamine/xylazine/acepromazine combination is a useful regimen for normovolemic animals when anesthetic duration greater than that produced by ketamine/xylazine alone is required.  相似文献   

11.
本研究分析了卷蛾亚科Torticinae(Lepidoptera)53个种前翅翅脉电脑录像,确立了一套利用翅脉图像计测来鉴定卷蛾种类的方法,并开发了一个对应的专家系统。这个方法首先测定卷蛾翅脉上的22个交点(vein point)的坐标,然后把这些坐标值做为鉴定的特征依据输入数据库。 当拿到要鉴定的标本时,先让电脑自动测定其各翅脉交点坐标,再求出它与数据库中的53个种的交点坐标的相异度(dissimilarity),最后在屏幕上显示出它与53个已知种的相异度名次,相异度越小,则说明彼此翅脉越相似,与要鉴定的标本是同种的可能性越大。模拟实验的结果,名列第一的准确率高达98.2%,名列第二、第三的准确率为1.8%。 为了保证100%的准确率,本系统还将这53个已知种的成虫形态图、雌雄外生殖器解剖图、以及形态文字描述、生活习性、分布、寄主等也输入本系统。这些资料可以随时提取、配合鉴定。这一专家系统不受语言和专业程度限制,既简单迅速又准确,不失为鉴定卷蛾种类的一个好的新方法。  相似文献   

12.
γ射线与咖啡因复合处理对大麦的诱变效应   总被引:1,自引:0,他引:1  
用五种不同剂量的γ射线和5mmol/L咖啡因对大麦种子进行单独处理和γ射线与咖啡因间的复合处理,结果表明,辐照M1代的细胞学损伤及植株损指标均与辐照剂量呈直线相关,且相关系数达显著或极显著水平;M2代苗期的叶绿素突变率和性状弯异率均与辐照剂量呈指数函数关系,相关系数也均达显著或极显著水平。咖啡因本身对大麦不具诱变性,但以它作辐射后处理,不仅能加剧M1代细胞学损伤及植株损伤,而且能提高M2代叶绿素突  相似文献   

13.
In this study, a novel generic hapten of phenothiazine drugs was synthesized by derivatization of 2-chlorophenothiazine with sodium bromoacetate. Then the hapten was coupled to bovine serum albumin for production of the monoclonal antibody. Results showed that the obtained monoclonal antibody recognized five phenothiazine drugs simultaneously: chlorpromazine, promethazine, acepromazine, perphenazine, and fluphenazine. After evaluation of different coating antigens, a heterologous competitive indirect enzyme-linked immunosorbent assay was developed to determine the residues of the five phenothiazine drugs in swine tissues (muscle, liver, and kidney). The cross-reactivities to the five analytes were in the range of 71 to 98%, and the limits of detection were in the range of 0.2 to 0.4 ng/ml, depending on the drug. Their recoveries from the fortified blank samples were in the range of 73.8 to 96.2%, with coefficients of variation in the range of 4.1 to 14.3%. This is the first study reporting a broad specific immunoassay for multi-determination of the residues of five phenothiazine drugs in animal-derived foods.  相似文献   

14.
目的 :检测复合益生菌制剂“海生元”制备储存各阶段益生菌的存活数量及其生物表型的稳定性 ,以判定该制剂的效力稳定性。方法 :在有效期内 (1年 ) ,每月定期随机取 5个“海生元”胶囊 ,按常规对M9(乳杆菌QJ4 0 5 )和T9(双歧杆菌QJ4 0 5 )两株益生菌进行活菌培养计数和菌种鉴定。结果 :(1)在常温保存条件下的一年效期内 ,制剂中的 2种益生菌 (M9和T9)存活数量略有下降趋势 ,但各次结果均符合产品的效力要求 (活菌数 >10 8/ g)。 (2 )M9和T9各次纯培养的形态学、生化反应模式及终末代谢产物气相色谱定量分析结果均分别符合其乳杆菌和双歧杆菌的菌种鉴定特征。结论 :复合益生菌制剂“海生元”在常温保存的 1年有效期内 ,可保持制剂中益生菌的活菌数量及稳定的生物表型特征 ,从而保证该制剂的效力稳定性和疗效要求。  相似文献   

15.
目前甘肃鼢鼠Myospalax cansus、高原鼢鼠 M.baileyi、秦岭鼢鼠M.rufescens的分类地位一直存有争议,多涉及到与中华鼢鼠M.fontanierii的分类关系.本文分别从成体甘肃鼢鼠、高原鼢鼠、秦岭鼢鼠、中华鼢鼠标本的胡须、头部、背部、腹部、前肢取毛样,经清洗和处理后,在倒置显微镜下观察,用目镜测微尺分别测量和计算其5个部位毛发的毛髓质指数.结果表明:甘肃鼢鼠与中华鼢鼠除胡须髓质指数无显著性差异外,其它部位及各部位综合均有显著差异.高原鼢鼠与秦岭鼢鼠除前肢毛髓质指数无显著性差异外,其它部位及各部位综合均有显著差异;与中华鼢鼠除前肢毛髓质指数无显著差异,其它部位及各部位综合均有显著差异.秦岭鼢鼠除与甘肃鼢鼠的腹部及与中华鼢鼠、高原鼢鼠的前肢毛髓质指数无显著差异外,与其它鼢鼠其余部位及各部位综合均有显著性差异.综合考虑,本研究结果支持甘肃鼢鼠、高原鼢鼠、秦岭鼢鼠各自独立为种的观点.  相似文献   

16.
Epinephrine and related drugs (sympathomimetic amines) are the only compounds which effectively increase the rhythmic function of the heart.Effects of two new non-pressor sympathomimetic compounds were observed. One of these compounds, the isopropyl homologue of epinephrine, was found to be about five times more active than epinephrine.From clinical observations on the action of a new cardiac depressant drug, alpha-fagarine, it was concluded that the drug is very effective but that toxic reactions are unpredictable.The potency of alpha-fagarine and related compounds suggests the possible development of chemically related non-toxic drugs having an effective cardiac depressant action.  相似文献   

17.
生境破碎化对黑白仰鼻猴种群数量的影响   总被引:13,自引:0,他引:13       下载免费PDF全文
从1999年4月至2002年6月间,对黑白仰鼻猴种群的分布和生境状况进行了调查。与十年前的调查结果相比,本次调查新发现了4个猴群,但有5个以前存在的猴群已经消失,现存种群数量为13个猴群,总体数量约为1200─1700只。从西藏的芒康到云龙的龙马山,随着海拔的降低,猴群可利用的植被类型也随之多样化。但由于砍伐、放牧、开矿等因素的影响,猴群的适宜生境破碎化程度较高,连接猴群的生境走廊状况通常较差,多数猴群孤立分布,并且存在小种群问题,生境走廊的维护和恢复已成为该物种保护成功与否的关键。种群的总体数量下降了32%,其中4个猴群数量下降,4个猴群持平,1个猴群有所增长,5个猴群消失,这不容乐观的状况给我们的保护工作敲响了警钟。  相似文献   

18.
Partially acetylated generation five polyamidoamine (PAMAM) dendrimer (G5-Ac) was reacted with biotin and 2-(p-isothiocyanatobenzyl)-6-methyl-diethylenetria minepentaacetic acid (1B4M-DTPA), respectively to form the complex Bt-G5-Ac-1B4M which was further conjugated with avidin to give the conjugate Av-G5-Ac-1B4M. Then both of the conjugates were radiolabeled with technetium-99m ((99m)Tc), respectively. Their in vitro cellular uptake study shows that the conjugate of Av-G5-Ac-1B4M-(99m)Tc exhibits much higher cellular uptake in HeLa cells than that of Bt-G5-Ac-1B4M-(99m)Tc. Accordingly the following evaluation such as in vitro/in vivo stability, biodistribution and micro-SPECT imaging was observed only for the conjugate of Av-G5-Ac-1B4M-(99m)Tc.  相似文献   

19.
A thermostable archaeal l -aminoacylase from Thermococcus litoralis has been used in immobilisation trials to optimise its application in industrial biotransformation reactions. Immobilisation techniques used included direct adsorption and crosslinking of the enzyme onto solid supports, bioencapsulation, and covalent bonding onto a variety of activated matrices. The most successful immobilisation methods were covalent binding of the enzyme onto glyoxyl-Sepharose and Amberlite XAD7. These methods yielded an average of 15 and 80 mg of protein bound per gram of support (wet weight for glyoxyl-Sepharose), respectively, with nearly 80% activity recovery in both cases. Enzyme immobilised onto glyoxyl-agarose was stabilised 106-fold under aqueous conditions and 142-fold in 100% acetonitrile when activity was measured after 24 h at 90°C. A column bioreactor containing the recombinant l -aminoacylase immobilised onto Sepharose beads was constructed with the substrate, N -acetyl- dl -Trp, continuously flowing at 60°C for 10 days. No loss of activity was detected over five days, with 32% activity remaining after 40 days at 60°C. These results show the potential of the use of immobilised l -aminoacylase in biotransformation reactions for the production of fine chemicals.  相似文献   

20.
A thermostable archaeal l -aminoacylase from Thermococcus litoralis has been used in immobilisation trials to optimise its application in industrial biotransformation reactions. Immobilisation techniques used included direct adsorption and crosslinking of the enzyme onto solid supports, bioencapsulation, and covalent bonding onto a variety of activated matrices. The most successful immobilisation methods were covalent binding of the enzyme onto glyoxyl-Sepharose and Amberlite XAD7. These methods yielded an average of 15 and 80 mg of protein bound per gram of support (wet weight for glyoxyl-Sepharose), respectively, with nearly 80% activity recovery in both cases. Enzyme immobilised onto glyoxyl-agarose was stabilised 106-fold under aqueous conditions and 142-fold in 100% acetonitrile when activity was measured after 24 h at 90°C. A column bioreactor containing the recombinant l -aminoacylase immobilised onto Sepharose beads was constructed with the substrate, N -acetyl- dl -Trp, continuously flowing at 60°C for 10 days. No loss of activity was detected over five days, with 32% activity remaining after 40 days at 60°C. These results show the potential of the use of immobilised l -aminoacylase in biotransformation reactions for the production of fine chemicals.  相似文献   

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