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901.
V. M. LUCRE D. F. KELLY† P. G. G. DARKER ‡ C. J. GASKELL 《The Journal of small animal practice》1980,21(3):169-181
The clinico-pathological findings are described in thirteen young dogs with advanced renal disease. All but three dogs were less than 2 years old. Some had signs of renal dysfunction since birth. Presenting signs were variable but anorexia, lethargy and weight loss were most frequent. All dogs had raised blood urea levels and most passed dilute urine; proteinuria and anaemia were variable findings. At necropsy all dogs had extra-renal lesions of renal failure and finely granular or lobulated, shrunken kidneys. The microscopical appearances of the kidneys were not those of amyloidosis, inflammatory or glomerular disease but were considered likely to be of developmental origin. The renal lesions were divided into three histologically distinct groups.
- 1 Predominantly cystic and connective tissue changes, characterized by striking dilatation of glomerular capsular spaces and cortical tubules.
- 2 Atypical connective tissue changes in which there were segmental bands of fibrous tissue containing primitive glomerular and tubular structures.
- 3 Predominantly glomerular and connective tissue changes, characterized by varying degrees of glomerulosclerosis and widespread calcification of glomeruli, tubules and blood vessels.
902.
903.
Embryo transfer: a discussion on its potential for infectious disease control based on a review of studies on infection of gametes and early embryos by various agents 总被引:1,自引:1,他引:0 下载免费PDF全文
Eaglesome MD Hare WC Singh EL 《The Canadian veterinary journal. La revue veterinaire canadienne》1980,21(4):106-112
Studies on laboratory animals have shown that viruses vary as to whether or not they are transmissible by the gametes or are capable of passing through the zona pellucida and infecting the embryo.
Methods of studying early embryos for the presence of infectious agents include electron microscopy, immunocytochemistry and cell cultivation.
Determination that early bovine embryos do not become infected by certain agents might allow for easing of restrictions in the current import and export regulations for cattle embryos.
Embryo transfer could be used as a means of controlling or eliminating disease in a herd or flock if the causal agent does not infect the early embryo via the gametes or by penetrating the zona pellucida.
相似文献904.
Field studies with convalescent serum and infectious bursal disease vaccine to control turkey coryza
Convalescent serum given to 1-day-old poults delayed clinical signs of turkey coryza by several days and reduced mortality on infected farms. Turkey breeders immunized with cell-culture-adapted infectious bursal disease virus (IBDV) or turkey infectious bursal disease virus (TIBDV) had a marked increase in virus-neutralization (VN) antibody titers. The VN antibody titer was significantly higher in progeny poults than in poults from unimmunized breeders. Clinical turkey coryza and mortality was considerably less in poults from IBD- or TIBD-vaccinated breeders than in control poults. They also responded more favorably to hemorrhagic enteritis and fowl cholera vaccination. 相似文献
905.
Ring- and carboxyl-labelled [14C]2,4-D were incubated under laboratory conditions, at the 2 g/g level, in a heavy clay, sandy loam, and clay loam at 85% of field capacity and 20 1C. The soils were extracted at regular intervals for 35 days with aqaeous acidic acetonitrile, and analysed for [14C]2,4-D and possible radioactive degradation products. Following solvent extraction, a portion of the soil residues were combusted in oxygen to determine unextracted radioactivity as [14C]carbon dioxide. The remaining soil residues were then treated with aqueous sodium hydroxide, and the radioactivity associated with the fulvic and humic soil components determined. In all soils there was a rapid decrease in the amounts of extractable radioacitivity, with only 5% of that applied being recoverable after 35 days. All recoverable radioactivity was attributable to [14C]2,4-D, and no [14C]-containing degradation products were observed. This loss of extractable radioactivity was accompanied by an increase in non-extractable radioactivity. Approximately 15% of the applied radioactivity, derived from carboxyl-labelled [14C]2,4-D, and 30% from the ring-labelled [14C]2,4-D was associated with the soil in a non-extractable form, after 35 days of incubation. After 35 days, less than 5% of the radioactivity from the carboxyl-labelled herbicide, and less than 10% of the ringlabelled material, was associated with the fulvic components derived from the three soils. Less than 5% of the applied radioactivities were identifiable with any of the humic acid components. It was considered that during the incubation [14C]2,4-D did not become bound or conjugated to soil components, and that non-extractable radioactivity associated with the three soil types resulted from incorporation of radioactive degradation products, such as [14C]carbon dioxide, into soil organic matter. 相似文献
906.
Studies were conducted in the green house on 14C-methyllabelled glyphosate translocation in johnsongrass as affected by rhizome length and growth stage. The amount of 14C measured by the liquid scintillation technique in the rhizomes (2-8%) increased with rhizome length (10, 20 or 30 cm) and tended to increase with growth stage (15-30 cm tall, 45-60 cm tall, or at seedhead), but the amount of 14C per g fresh rhizome weight was almost similar in all cases. Of the total amount applied per plant (0·2 μCi) about 1/3 or less remained on the treated leaf area, while another 1/3 was a absorbed into the treated leaves. Autoradiographs showed that the 14C label moved to all plant parts, basipetally and acropetally. Migration du glyphosate 14 C chez le sorgho d'Alep (Sorghum halepense L. Pers.) en relation avec le stage de croissance et la longueur du rhizome Des recherches ont été effectuées en serru sur la migration du glyphosate marqué au 14C sur le méthyle, chez le sorgho d'Alep, en relation avec la longueur du rhizome et le stade de croissance. La quantité de 14C mesurée par la technique de scintillation liquide dans les rhizomes (2 à 8%) s'est accrue avec la longueur du rhizome (10, 20 ou 30 cm) et elle a eu tendance à augmenter avec le stade de croissance (Hauteur 15-30 cm, hauteur 45-60 cm ou épiaison), mais la quantité de 14C par gramme de poids frais de rhizome est restée Presque identique dans tous les cas. Environ 1/3, ou moins, de la quantitéà la surface des feuilles traitées par plante (0,2 μCi), est restéà la surface des feuilles traitées cependant qu'un autre 1/3 a été absorbé dans less feuilles traitées Les autoradiographies ont montré que le 14C marqueur a migré dans toutes les parties de la plante, dans le sens basipète et dans le sens acropète. Translokation von 14C-Glyphosat in Johnsongras (Sorghum halepense L. Pers.) in Abhängigkeit vom Wachstumsstadium der Pflanzen und der Rhizomlänge Im Gewächshaus wurden Versuche über die Translokation von 14C-Glyphosat in Johnsongras (Sorghum halepense L. Pers.) in Abhängigkeit vom Wachstumsstadium der Pflanzen und der Rhizomlänge durchgeführt. An den Rhizomen stieg der Gehalt von 14C(2–8%), gemessen mit der Flüssig-Szintillationstechnik, mit zunehmender Rhizomlänge (10, 20 oder 30 cm) an und nahm tendenziell auch mit fortschreitendem Pflanzenwachstum zu (15–30 cm und 45–60 cm Sprosslänge oder nach dem Rispenschieben); jedoch blieb die Menge pro g Rhizomfrischgewicht beinahe konstant. Von der insgesamt ausgebrachten Menge pro Pflanze (0.2 μCi) blieben bis zu 1/3 auf der behandelten Blättern absorbiert wurde. Die Autoradiographie zeigte, dass der 14C markierte Teil in alle Pflanzenteile sowohl basipetal wie auch akropetal transportiert wurde. 相似文献
907.
Absorption and translocation of 14C fosamine (ethyl hydrogen (aminocarbonyl) phosphonate) and/or fosamine metabolites were monitored in intermediately susceptible seedling black cherry (Prunus serotina Ehrh.) and resistant seedling rhododendron (Rhododendron sp.) and magnolia (Magnolia sp.). The mid two-thirds of the third leaf below the apical bud of each plant was treated with 0·5 μCi 14C fosamine (carbonyl carbon labelled). Plants were harvested 3, 7 and 14 days following treatment. In black cherry the majority of 14C absorption and translocation occurred during the second week following treatment, while magnolia and rhododendron translocated and absorbed most of the 14C within 3 days after treatment. Retention of 14C in the treated portion of the treated leaf did not differ between species. However, total translocated 14C was greatest in black cherry, less in magnolia, und minimal in rhododendron. Magnolia translocated 14C basipetally, while black cherry translocated acropetally, as well as basipetally. Absorpiion et migration de la fosamine 14C chez trois espèces de plantes ligneuses L'absorptlon et la migration de La 14C fosamine ((amino carbonyl) phosphonate d'éthyle hydrogène) et/ou de ses métabolites, ont étéétudiées chez des plantules moyennement sensibles de Prunus serotina (Ehrh.) et chez des plantules résistantes de rhododendron (Rhododendron sp.) et de magnolia (Magnolia sp). Les deux tiers moyens de la troisième feuille en-dessous du bourgeon apical de chaque plant ont été traités avec 0.5 Ci 14C de fosamine (marquée sur le carbone du carbonyl). Les plantes ont été récoltées 3, 7 et 14 jours après le traitement. Chez P. serotina, la plus grande partie de l'absorption et de la migration du 14C a eu lieu durant la deuxième semaine après le traitement, alors que chez le magnolia et le rhododendron, le maximum d'adsorption et de migration s'est situé dans les trois jours qui ont suivi le traitement. La rétention du 14C dans la partie traitée n'a pas variè d'une espèce à l'autre. Toutefois, la quantité totale de 14C qui a migré a été plus grande chez P. serotina, moindre chez le magnolia et minimaie chez le rhododendron. Chez le magnolia, la migration du 14C s'opere dans le sens basipète, alors que chez le P. serotina. elle s'effectue aussi bien dans le sens acropète que dans le sens basipète. Aufnahme- und Trunstokaiion von 14C-Fosaminc bei drei Gehölzpflanzen Es wurde die Aufnahme und die Translokation von 14C Fosamine (O-Äthyl-aminocarbonylphosphonsäure) und/oder seiner Abbauprodukte bei drei Gehölzarten beobachtet. Verwendet wurden Sämlinge der Traubenkirsche (Prunus serotina Ehrh.), die eine mittlere Empfindlichkeit zeigt und Sämlinge des resistenten Rhododendron (Rhododendron sp.) und der ebenfalls resistenten Magnolie (Magnolia sp.). Die mittleren zwei Drittel des dritten Blattes unterhalb der Endknospe wurden bei jeder Pflanze mit 0.5 μCi 14C-Fosamine (markiert am Carbonylkohlenstoff) behandelt. Die Pflanzen wurden nach 3, 7 und 14 Tagen nach der Behandlung geerntet. Bei der Traubenkirsche wurde während der zweiten Woche am meisten 14C aufgenommen und transloziert, während dies bei der Magnolie und dem Rhododendron bereits innerhalb der ersten drei Tage der Fall war. Bezüglich der Retention von 14C in der behandelten Blattfläche unterschieden sich die drei Arten nicht. In der Traubenkirsche wurde aber am meisten 14C transloziert, weniger in der Magnolie und am wenigsten im Rhododendron. Die Magnolie translozierte das 14C basipetal, während die Traubenkirsche akropetal wie basipetal translozierte. 相似文献
908.
Twenty-seven compounds were screened as potential inhibitors of juvenile hormone esterases. Of these compounds O-ethyl-S-phenyl phosphoramidothiolate provided the best inhibition for the cabbage looper, Trichoplusia ni (Hubner), and the yellow mealworm, Tenebrio molitor L., while the juvenile hormone esterases of the house fly, Musca domestica L., were best inhibited by a juvenoid carbamate (1-(m-phenoxy-N-ethyl carbamate)-3,7-dimethyl-7-methoxy-2E-octene). The inhibition patterns of T. ni and T. molitor are similar, while those of M. domestica are relatively different. Further studies on the juvenile hormone and α-napthyl acetate esterases of T. ni showed that they could be differentially inhibited. Diisopropyl phosphorofluoridate and an alkyl trifluoromethyl ketone selectively inhibit the hydrolysis of α-naphthyl acetate and juvenile hormone, respectively, while O-ethyl-S-phenyl phosporamidothiolate inhibits both enzymes. The juvenile hormone esterases of T. ni also appear to be unique enzymes that are selective for juvenile-hormone-like molecules. The in vivo inhibition of T. ni juvenile hormone esterases by O-ethyl-S-phenyl phosphoramidothiolate slows the in vivo hydrolysis of juvenile hormone and results in delayed pupation and malformed larvae that resemble larval-pupal intermediates. Thus, the esterases involved in juvenile hormone metabolism appear to be important in juvenile hormone regulation. 相似文献
909.
Amin A. Nomeir Nicolas P. Hajjar Ernest Hodgson Walter C. Dauterman 《Pesticide biochemistry and physiology》1980,13(2):112-120
EPN is twice as toxic as EPNO to house flies from both the Diazinon-resistant strain and the susceptible strain. EPN and EPNO are also eight times more toxic to the susceptible than the resistant strain. This is due to the ability of the resistant strain to metabolize these compounds to a greater extent. Metabolism by the glutathione S-transferases present in the 100,000g supernatant is more extensive than that by the NADPH-dependent microsomal mixed-function oxidases. The glutathione S-transferases are the major route of metabolism for EPN and appear to be the principal mechanism conferring resistance. EPN was metabolized by the microsomal fraction via oxidative desulfuration to the oxygen analog, EPNO, and by oxidative dearylation to p-nitrophenol. EPNO was metabolized by the same system to p-nitrophenol and desethyl EPNO as well as to an unknown metabolite. The soluble fraction metabolized EPN to p-nitrophenol, S-(p-nitrophenyl)glutathione, O-ethyl phenylphosphonothioic acid, and S-(O-ethyl phenylphosphonothionyl)glutathione. The identification of the latter conjugate demonstrates a new type of metabolite of organophosphorus compounds. EPNO was metabolized by the soluble fraction to p-nitrophenol and S-(p-nitrophenyl)glutathione. 相似文献
910.
胡桃长足象是核桃果实的大害虫,为害损失很大。1975年以来,我们在四川平武地区进行了生活习性观察和防治试验,初步明确了以下几个问题。1.胡桃长足象一年一代。11月份以成虫越冬,次年4月上旬开始活动,为害果、芽、嫩枝、叶柄,5月上旬交尾产卵于果中,一般一果一粒,8月中旬产卵结束,10月陆续死亡。当年成虫6月中旬羽化,进行为害。2.成虫有假死性和向阳性,飞翔力弱,具有与核桃树芽苞相似的保护色。3.防治胡桃长足象,应抓住越冬成虫大量出现和卵孵化盛期时进行。用每毫升含孢量二至五亿的白僵菌液或50%的三硫磷乳油、50%速灭松乳剂、82%磷胺乳剂加水一千倍喷雾,效果良好。 相似文献