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排序方式: 共有1482条查询结果,搜索用时 15 毫秒
1.
Growth of triploid oyster, Crassostrea madrasensis (Preston)   总被引:1,自引:0,他引:1  
The performance of I and II meiotic triploids and control oysters (Crassostrea madrasensis) reared at Tuticorin Bay was compared to determine if the improvements in the growth of edible oysters were additive to faster growth in triploids. After a grow‐out period of 12 months, both mean whole weights and shell heights were in order I meiotic triploid>II meiotic triploid>control. Mean whole weights and shell height of different oyster lines were all significantly different (P<0.05). On an average, larger morphological traits indicated that growth improvements from triploids were additive, and throughout the study triploid oysters maintained faster growth rate than their diploid siblings. Condition index and adductor muscle diameter of both triploids were higher than those of control.  相似文献   
2.
This paper depicted the physiographic landscape features and natural vegetation situation of study area (the eastern Jilin Province), and expatiates the definition, basic characters and its development of Ecological Land Classification (ELC). Based on the combination of relief map, satellite photography for study area and vegetation inventory data of 480 sample sites, a 5-class and a 15-class ecological land type map was concluded according to 4 important factors including slope, aspect, vegetation and elevation. Ecological Classification System (ECS) is a method to identify, characterize, and map ecosystems. The Ecological Land Type (ELT) was examined and applied initially in eastern Jilin Province. Foundation item: This paper was supported by Chinese Academy of Sciences “100 people” project and the Open Research Station of Changbai Mountain Forest Ecosystem. Biography: XIAO Bao-ying (1974-), female, postgraduate in Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, P. R. China Responsible editor: Zhu Hong  相似文献   
3.
I—ELISA特异诊断棘球蚴(包虫)病的研究   总被引:1,自引:1,他引:0  
采用亲和层析技术纯化的兔抗棘球蚴抗体,建立了酶联免疫吸附抑制试验(I—ELISA)。取代反应和阻断反应均无非特异反应;检测健康对照血清126份(人36,猪90),均为阴性;与猪囊尾蚴病血清136份(人46,猪90)、细颈囊尾蚴病血清38份(羊22、猪16)无交叉反应;对棘球蚴病血清183份(人61、羊71、猪51)进行检测,其阳性符合率分别为88.5%(54/61)、98.6%(70/71)、96.1%(49/51)。  相似文献   
4.
绵羊角的有无是由或主要由一个基因位点(Locus)上的三个等位基因(H、h’、h)所决定。三个等位基因的遗传方式是:H为显性无角基因,对h为完全显性,即Hh基因型均表现无角性状;h为隐性有角基因,即hh基因型均表现有角性状;h,为一个频率很低的基因,对h为不完全显性,即h'h基因型仍表现为有角性状;但H对h’基因为不完全显性,即Hh’基因型可能出现角痕(角突或角基)。而h’h’基因型公羊表现为小角、发育残缺不全的矫型角,母羊表现为无角。培育无角革的关键是选择使用无角公羊,通过测交试验能确定无角公羊基因的纯合度,从而决定如何使用。  相似文献   
5.
6.
已构建的能表达大肠杆菌K88ac-ST1-LTB融合蛋白的工程菌株BL21(DE3)(pXKST3LT5)及其表达产物经动物试验证实没有毒性反应。用从IPTG诱导的工程菌中提取的包涵体或经甲醛灭活的工程菌制成抗原,免疫小鼠,结果免疫小鼠至少能抵抗2MLD的大肠杆菌强毒株C83902(K88ac,ST^ ,L^ )的攻击,用提取的包涵体免疫家兔后,采集的血清能够中和天然ST1的毒性,这表明构建的工程菌株BL21(DE3)(pXKST3LT5)可以作为预防幼畜大肠杆菌性腹泻基因工程菌苗的候选株。  相似文献   
7.
试验于1992~1994年在山东和北京的6个地区,14个苹果园进行。田间试验表明,用灭菌肥Ⅰ型50倍液涂治苹果树腐烂病患处,平均治愈率可达90%以上,比对照2%福美砷当年平均治愈率提高7.22─29.51%,周年平均治愈率提高18.05%~32.39%,愈伤组织宽度增加3.03%~29.23%。室内试验表明,灭菌肥Ⅰ型最低抑菌剂量1000倍,抑菌面积可达2289.06mm2。  相似文献   
8.
An intravenous bile acid loading test was performed on 16 goats using various dosages and sampling protocols. A recently developed enzymatic bile acid assay provided an economical and technologically simple method for bile acid analysis. Intravenous injection of bile salts into goats was well tolerated. Clearance times were rapid. A protocol for performance of the test was suggested and a practical reference range for T 1/2 clearance of 4+/-1 minute was determined. Further investigations of this test in the assessment of liver function in the ruminant appear warranted.  相似文献   
9.
Type III procollagen peptide (P-3-P) is a serum marker for hepatic fibrosis in humans. The utility of a commercially available radioimmunoassay for P-3-P was evaluated in the dog. The specificity of the assay was assessed by polyacrylamide gel electrophoresis (PAGE) of canine serum and purified bovine P-3-P, followed by Western immunoblotting with rabbit aniti-P-3-P serum. The sensitivity was assessed by performing the radioimmunoassay on dilutions of sera from 22 dogs. Polyacrylamide gel electrophoresis of purified bovine P-3-P and sera from two dogs suspected of having elevated P-3-P concentrations revealed no homologous bands of staining. Western immunoblotting showed marked cross-reactivity of the high antisera concentrations with several components of the serum proteins, but none corresponding to the purified P-3-P. All tested sera from dogs had minimal competitive binding with radiolabeled P-3-P in the radioimmunoassay. Dilution curves of dog sera did not parallel either the standard curve or the dilution curve of a known test human serum. There were no statistically different P-3-P concentrations in any of the groups of dogs studied. It was concluded that currently available radioimmunoassay kits for the measurement of P-3-P in the human are not applicable in the dog. Seemingly, the structure or metabolism of canine P-3-P may vary significantly from that of the bovine or human, limiting the sensitivity and specificity of this assay in the dog.  相似文献   
10.
以川梨、砂梨、豆梨和杜梨为材料,研究了在缺铁胁迫下培养介质的pH值和根系Fe3+还原酶活性的变化。结果表明,缺铁胁迫使4种砧木的介质pH值于处理的第2天就迅速降低,并且一直低于低铁和正常供铁处理;而低铁处理下,介质pH值在最初几天内反而高于正常处理,至4~5d之后才逐渐低于正常供铁处理;同时,NH4+-N对降低介质pH值和缓解缺铁症状有利。4种砧木的根系Fe3+还原酶活性都随供铁浓度的增加而不同程度的增大:无铁处理下,砂梨根系Fe3+的还原能力最小、杜梨最大;而在低铁和正常供铁条件下,砂梨和川梨的还原能力最强,杜梨次之,豆梨最小。还原酶大小与症状表现之间具有一致性。  相似文献   
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