异育银鲫幼鱼对饲料中维生素B6需求量的研究

通过8周的生长实验,研究饲料中维生素B6的含量对异育银鲫(Carassius auratas gibelio)(初始体重3.3 g)生长、饲料利用及生化指标的影响。配制7组等氮等能的饲料,饲料中维生素B6的含量分别为0、1.11、3.29、5.41、12.7、13.3和27.3 mg/kg。实验结果表明,饲料中缺乏维生素B6会显著降低异育银鲫的特定生长率、饲料转化效率、蛋白质效率、存活率、肝体指数,但对摄食率没有显著影响。饲料中维生素B6的含量为12.70 mg/kg时,肝脏谷草转氨酶活性(GOT)活性最强,并且显著高于对照组(P<0.05)。在饲料中维生素B6含量为5.41 mg/kg时,肝脏谷丙转氨酶活性(GPT)活性显著提高。当饲料中维生素B6含量为12.7 mg/kg时,肝脏中维生素B6的沉积最高。通过折线法,根据特定生长率和饲料中维生素B6含量的关系,得出异育银鲫最大生长时饲料维生素B6的适宜含量为0.95 mg/kg;而以肝脏GOT和GPT活性为指标时,其饲料维生素B6的适宜含量分别为11.36和7.62 mg/kg。     

维生素E对三氯乙烯急性染毒大鼠

本文观察了用抗氧化剂维生素E预处理后,三氯乙烯(3000mg/kg B.W.)一次性经口染毒24h大鼠肝脏的超氧化物歧化酶、谷胱甘肽过氧化物酶等抗氧化酶活力及丙二醛含量的变化,结果表明三氯乙烯染毒组肝脏中丙二醛含量、超氧化物歧化酶活力及血清谷丙转氨酶、谷草转氨酶活力均高于对照组(P＜0.01);而维生素E干预组的丙二醛含量、超氧化物歧化酶活力及血清谷丙转氨酶、谷草转氨酶活力均分别低于三氯乙烯染毒组(P＜0.01),说明三氯乙烯急性染毒可引起肝脏脂质过氧化反应及肝损害,肝脏超氧化物歧化酶活力升高可能是机体受自由基及脂质过氧化反应刺激而诱导产生的一种适应性反应,维生素E对三氯乙烯所致的肝损害有一定的保护作用。     

维生素E对三氯乙烯急性染毒大鼠肝脏脂质过氧化与抗氧化酶的影响

本文观察了用抗氧化剂维生素E预处理后,三氯乙烯(3000mg/kg B-W-) 一次性经口染毒24h 大鼠肝脏的超氧化物歧化酶、谷胱甘肽过氧化物酶等抗氧化酶活力及丙二醛含量的变化,结果表明三氯乙烯染毒组肝脏中丙二醛含量、超氧化物歧化酶活力及血清谷丙转氨酶、谷草转氨酶活力均高于对照组(P< 0-01) ;而维生素E干预组的丙二醛含量、超氧化物歧化酶活力及血清谷丙转氨酶、谷草转氨酶活力均分别低于三氯乙烯染毒组(P< 0-01) ,说明三氯乙烯急性染毒可引起肝脏脂质过氧化反应及肝损害,肝脏超氧化物歧化酶活力升高可能是机体受自由基及脂质过氧化反应刺激而诱导产生的一种适应性反应,维生素E对三氯乙烯所致的肝损害有一定的保护作用。     

饲喂不同浓度黄曲霉毒素B1饲料对异育银鲫成鱼的生长和毒素积累的影响

以含不同浓度黄曲霉毒素B1(AFB1)的配合饲料饲喂异育银鲫(Carassius auratus gibelio)成鱼56d,研究异育银鲫成鱼[(122.3±0.7)g]生长、生理反应、肝脏组织学变化、卵巢发育以及鱼体各组织中的AFB1的毒素积累状况。实验分为5个实验组,不同实验组饲料中AFB1含量分别为0、5、20、50、500μg/kg饲料(实测值分别为2.59、4.12、12.39、46.23、454.07μg/kg饲料),每个处理3个平行。在整个实验过程中各实验组均未表现出外部形态和行为异常,各组存活率均达到100%。各实验组异育银鲫成鱼终末体重、摄食率(FR)、特定生长率(SGR)和饲料效率(FE)均无显著差异。饲料AFB1水平对异育银鲫血清总胆固醇(TC)含量、血清谷丙转氨酶(GPT)、谷草转氨酶(GOT)和碱性磷酸酶(AKP)活性均无显著影响。各毒素组血清超氧化物岐化酶(SOD)活性与对照无显著差异。各毒素组肝脏和卵巢均未见明显的组织学病理变化。肌肉和性腺中的AFB1积累量低于FDA食品安全限定标准(5μg/kg)。肝胰脏中的AFB1积累和饲料中的AFB1水平呈对数关系。饲喂AFB1≥50μg/kg饲料使异育银鲫成鱼肝脏AFB1积累超过安全限量标准。结果表明,异育银鲫成鱼至少可耐受AFB1含量达500μg/kg饲料(实测值:454.07μg/kg饲料)56d。     

团头鲂幼鱼吡哆醇适宜需求量的研究

试验采用单因素试验设计, 以饲料中吡哆醇浓度为影响因素, 研究了团头鲂幼鱼的适宜吡哆醇需求量。试验共配置了7组等氮等能的半纯化饲料, 其吡哆醇的实际含量分别为0、1.04、1.99、4.07、5.91、7.96和9.22 mg/kg。选用840尾均重:(6.810.17) g团头鲂幼鱼, 随机分为7组, 每组4重复, 每重复30尾鱼, 日投饵3次, 养殖期为8周。结果表明, 当饲料中吡哆醇含量由0升高至5.91 mg/kg时, 团头鲂的增重率、特定生长率、饲料利用率、成活率、蛋白效率比和氮保留率均得到显著改善(P0.05); 当吡哆醇含量进一步升高至9.22 mg/kg时, 蛋白效率比和氮保留率均显著下降(P0.05), 而其他指标则无显著变化(P0.05)。饲料中的吡哆醇含量显著影响团头鲂的肝体比(P0.05)且以5.91 mg/kg组为最低, 但对肥满度和胴体率均无显著影响(P0.05)。当饲料吡哆醇含量由0升高至5.91 mg/kg时, 肝脏谷草转氨酶和谷丙转氨酶活性以及吡哆醇含量均显著升高(P0.05); 当吡哆醇含量进一步升高至9.22 mg/kg时, 三者均无显著变化(P0.05)。以肝脏中的谷丙和谷草转氨酶活性以及吡哆醇含量为评价指标, 拟合折线模型得到团头鲂幼鱼的适宜吡哆醇的需求量为4.175.02 mg/kg。       

苦瓜甾醇对对乙酰氨基酚致小鼠肝损伤的保护作用

本文研究苦瓜甾醇对对乙酰氨基酚所致小鼠肝损伤的保护作用及其作用机制。48只小鼠随机分为6组(n=8):正常对照组、模型组、阳性对照组和苦瓜甾醇低、中、高剂量(50、100和200 mg/kg)组。各剂量组小鼠给予苦瓜甾醇连续灌胃7 d后,一次性腹腔注射对乙酰氨基酚400 mg/kg制备肝损伤模型,测定肝组织和血清的生化指标。与各苦瓜甾醇组比较,模型组小鼠血清中谷丙转氨酶(ALT)、谷草转氨酶(AST)水平显著升高,白蛋白(ALB)、总蛋白(TP)含量显著降低,肝组织中丙二醛(MDA)含量升高,超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)活性下降。苦瓜甾醇有助于维持小鼠体内酶防御系统功能,提高清除自由基的能力,对对乙酰氨基酚所致小鼠肝损伤具有明显保护作用。     

苯并(a)芘与壬基酚对河川沙塘鳢的联合毒性研究

为探究环境内分泌干扰物联合毒性对鱼类的影响,选取苯并芘(benzo[a]pyrene,BaP)及千幕酚(4-nonlyphenol,NP)对河川沙塘鳢Odontobutis potamophila进行单独和联合毒性研究.研究了NP和BaP对河川沙塘鳢血清雌二醇(E2)、卵黄蛋白原(Vtg)、血清谷草转氨酶(GOT)以及肝脏7-乙氧基-3-异吩咏唑酮-脱乙基酶(7-ethoxyresoufin-O-deethylase,EROD)和超氧化物岐化酶(SOD)的影响.结果 表明,BaP单一暴露时,随着BaP剂量浓度的升高雌鱼血清E2含量下降,肝脏EROD活性升高;25 mg/kg BaP试验组雌鱼肝脏EROD活性显著高十对照组;肝脏SOD和血清GOT活性与对照无筹异;NP和BaP联合暴露中,200 mg/kg NP+10 mg/kg BaP、200 mg/kg NP+2 mg/kg BaP试验组雄性个体血清Vtg平均含量比200 mg/kg NP组低50%左右,而血清E2含最显著高于对照组,肝脏EROD酶活性、血清GOT活性变化与BaP剂量浓度呈正相关,而肝脏SOD酶活性则与BaP剂量浓度呈负相关;200 mg/kg NP+25 mg/kg BaP试验组肝脏SOD活性显著低于对照组,而血清GOT活性则显著高于对照组.显示NP和BaP联合作用时BaP可拮抗NP对雄鱼Vtg的诱导效应;200 mg/kg NP+2 mg/kg BaP可导致河川沙塘鳢肝脏肝细胞损伤.     

脂氧素受体激动剂BML-111对大鼠急性肝损伤的干预作用及其机制*

目的: 探索脂氧素对急性肝损伤的作用及机制。方法: SD大鼠24只随机分为4组(n=6):正常对照组:皮下注射橄榄油,剂量1.8 ml/kg。模型组:皮下注射40%四氯化碳(CCL4)油剂(橄榄油为溶剂),剂量3 ml/kg。BML-111治疗组:皮下注射Lipoxin受体激动剂BML-111,剂量1 mg/kg,30 min后处理同模型组。BOC-2阻断剂组:皮下注射Lipoxin受体阻断剂BOC-2,剂量50 μg/kg,30 min后处理同BML-111组。HE染色观察肝组织病理学变化,判断肝损伤情况。血清学检测血清谷丙转氨酶(ALT)及谷草转氨酶(AST)活性;试剂盒法检测大鼠肝组织中髓过氧化物酶(MPO)活性;ELISA法测定血清中血管紧张素转化酶(ACE)、血管紧张素转化酶2(ACE2)、血管紧张素II(AngII)、血管紧张素1-7(Ang-(1-7))的含量。Western blot检测肝组织中Ang II、Ang-(1-7)的蛋白含量。结果: 治疗组较模型组和阻断剂组的肝损伤程度减轻;BML-111降低CCL4损伤的大鼠血清中ACE、AngII的含量(P＜0.01)及升高血清中ACE2、Ang-(1-7)的含量(P＜0.01)。BML-111增加肝组织中Ang-(1-7)含量,降低CCL4损伤的大鼠组织中AngII含量。结论: 结果表明脂氧素受体激动剂BML-111对大鼠急性肝损伤的干预作用及其机制,可能与调节AngII和Ang-(1-7)有关。     

低温下饥饿胁迫对大黄鱼血清生化指标的影响

研究了在低温(13℃)下饥饿胁迫对9月龄大黄鱼血清生化指标的影响。将400尾大黄鱼随机分成两组,一组为实验组,不投喂饲料;另一组为对照组,定时投喂饲料。实验开始30 d后,测定大黄鱼11种血清生化指标。结果显示,实验组大黄鱼血清的尿酸(UA)、尿素(UREA)、总胆固醇(TC)、谷丙转氨酶(ALT)含量极显著高于对照组(P0.01),甘油三酯(TG)、钙离子(Ca2+)含量显著高于对照组(P0.05);而白蛋白(ALB)、谷草转氨酶(AST)含量极显著低于对照组(P0.01);血糖(GLU)、总蛋白(TP)、镁离子(Mg2+)含量在实验组与对照组之间则无显著性差异。实验组血清中的蛋白质代谢产物和脂类物质明显高于对照组,但是血糖和总蛋白含量没有显著差异。     

黔产毛蒟水提物对急性肝损伤小鼠的保护作用

探讨黔产毛蒟水提物(PTE)对四氯化碳(CCl_4)诱导小鼠急性肝损伤的保护作用及其作用机制。本研究中将50只昆明种小鼠随机分为5组,各组10只,分别为空白组、模型组(0.01 g/kg的0.15%CCl_4菜油溶液造模)、PTE组(低剂量组0.5 g/kg和高剂量组1.0 g/kg)和阳性对照组(联苯双酯0.15 g/kg)。检测各组小鼠谷丙转氨酶(ALT)、谷草转氨酶(AST)、肿瘤坏死因子(TNF-α)含量;测定肝组织匀浆中脂质过氧化产物丙二醛(MDA)含量及超氧化物歧化酶(SOD)活性;计算肝脏的湿重指数;HE染色法观察肝脏组织的病理学变化。与空白对照组相比,模型组血清ALT、血清AST、肝脏指数、肝组织MDA含量以及血清TNF-α明显增高(均P0.01),肝组织SOD活性明显降低(P0.01),肝组织病理损伤明显。与模型组相比,PTE高剂量组和阳性对照组血清ALT显著降低(P0.01),PTE低、高剂量组和阳性对照组血清AST、肝脏指数、肝组织MDA含量以及血清TNF-α含量均明显降低(P0.05或P0.01),肝组织SOD活性明显升高(P0.01),并减轻了肝组织病理损害。PTE可减轻CCl_4诱导的急性肝损伤,其机制可能与抗氧化、抑制TNF-α的产生有关。     

Plant-Parasitic Nematodes of South Viet Nam

Between 1974 and 1978, 2,842 identifications of plant-parasitic nematodes were made from more than 1,700 soil and plant samples collected in eight provinces of South Viet Nam. Species in nine genera—Helicotylenchus, Criconemoides, Meloidogyne, Pratylenchus, Tylenchorhynchus, Hoplolaimus, Hirschmanniella, Xiphinema, and Rotylenchulus—comprised 96.1% of the identifications; the remaining 3.9% were species of 11 genera. Fourteen genera were associated with rice which was grown on about 2,500,000 ha in 1970. Of these, Ditylenchus, Hirschmanniella, and Meloidogyne were most important. Ditylenchus angustus caused severe damage to about 50,000 ha of flooded rice in the Mekong Delta in 1976. Hirschmanniella spp. were found in all samples examined from flooded rice fields. Meloidogyne spp. were common in rice seedbeds, upland rice, and rice not kept flooded continuously. Meloidogyne and Pratylenchus spp. were found in roots of 22 of the 32 crop plants sampled. Little or no attempt was made in South Viet Nam to control nematodes.     

Identification key for European strand-forming house-rot fungi

An identification key for 20 common strand-forming indoor wood decay fungi is given. The key is based on observations of material from affected buildings and on wood samples that have been incubated in the laboratory. The key is with macro- and microscopic photographs.     

Multilocus phylogenetic analysis of the genus Aeromonas

A broad multilocus phylogenetic analysis (MLPA) of the representative diversity of a genus offers the opportunity to incorporate concatenated inter-species phylogenies into bacterial systematics. Recent analyses based on single housekeeping genes have provided coherent phylogenies of Aeromonas. However, to date, a multi-gene phylogenetic analysis has never been tackled. In the present study, the intra- and inter-species phylogenetic relationships of 115 strains representing all Aeromonas species described to date were investigated by MLPA. The study included the independent analysis of seven single gene fragments (gyrB, rpoD, recA, dnaJ, gyrA, dnaX, and atpD), and the tree resulting from the concatenated 4705 bp sequence. The phylogenies obtained were consistent with each other, and clustering agreed with the Aeromonas taxonomy recognized to date. The highest clustering robustness was found for the concatenated tree (i.e. all Aeromonas species split into 100% bootstrap clusters). Both possible chronometric distortions and poor resolution encountered when using single-gene analysis were buffered in the concatenated MLPA tree. However, reliable phylogenetic species delineation required an MLPA including several “bona fide” strains representing all described species.     

Bacterial flora in the alimentary tract of chickens infected with Eimeria brunetti and in chickens immunized with Eimeria maxima and cross-infected with Eimeria brunetti

Differential bacterial counts were made on the intestinal and caecal contents of chickens after inoculation with a standard dose of 320 000 freshly sporulated oocysts of Eimeria brunetti.     

Middle Pleistocene fossil Cercopithecidae from Asbole, Afar Region, Ethiopia

A sample of 117 fossil cercopithecids has been collected from the Middle Pleistocene site of Asbole, Afar Region, Ethiopia. A minimum of five species is present. There are two species of Cercopithecini, here recognized as cf. Chlorocebus aff. aethiops, and cf. Chlorocebus cf. patas. There are also two species of Papionini: Papio hamadryas ssp. indet. and Theropithecus oswaldi leakeyi. Finally, there is a single species of colobine present, Colobus sp. indet. The assemblage is chronologically constrained and is derived from sediments dated to approximately 600 ka. Within this sample Colobus sp. is by far the most common species present, outnumbering the other four species combined. The cercopithecid assemblage is most consistent with a woodland habitat, corroborating an earlier interpretation based on the non-primate fauna. Taxonomic, biogeographic, and evolutionary implications of the assemblage are also discussed.     

Semicircular canal system in early primates

Mammals with more rapid and agile locomotion have larger semicircular canals relative to body mass than species that move more slowly. Measurements of semicircular canals in extant mammals with known locomotor behaviours can provide a basis for testing hypotheses about locomotion in fossil primates that is independent of postcranial remains, and a means of reconstructing locomotor behaviour in species known only from cranial material. Semicircular canal radii were measured using ultra high resolution X-ray CT data for 9 stem primates (“plesiadapiforms”; n = 11), 7 adapoids (n = 12), 4 omomyoids (n = 5), and the possible omomyoid Rooneyia viejaensis (n = 1). These were compared with a modern sample (210 species including 91 primates) with known locomotor behaviours. The predicted locomotor agilities for extinct primates generally follow expectations based on known postcrania for those taxa. “Plesiadapiforms” and adapids have relatively small semicircular canals, suggesting they practiced less agile locomotion than other fossil primates in the sample, which is consistent with reconstructions of them as less specialized for leaping. The derived notharctid adapoids (excluding Cantius) and all omomyoids sampled have relatively larger semicircular canals, suggesting that they were more agile, with Microchoerus in particular being reconstructed as having had very jerky locomotion with relatively high magnitude accelerations of the head. Rooneyia viejaensis is reconstructed as having been similarly agile to omomyids and derived notharctid adapoids, which suggests that when postcranial material is found for this species it will exhibit features for some leaping behaviour, or for a locomotor mode requiring a similar degree of agility.