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911.
Cytogenetic and histological studies were carried out on an intersex horse which was diagnosed clinically as a cryptorchid. Surgery confirmed the horse to be a bilateral abdominal cryptorchid and histological examination revealed ovarian tissue associated with the left epididymis. Chromosome analysis of cultured cells from testicular tissue, ovarian tissue and skin revealed 64-XX and 64-XY make-up, the left gonad containing a greater preponderance of XX cells over XY cells. The external characteristics and behaviour of the horse were indistinguishable from that of a "routine" cryptorchid. Other cases of equine intersexes are reviewed and theories for the discrepancies between genetic, gonadal and phenotypic sex are discussed. 相似文献
912.
Etiology of the stomatitis pneumoenteritis complex in Nigerian dwarf goats. 总被引:3,自引:1,他引:2 下载免费PDF全文
F M Hamdy A H Dardiri O Nduaka S S Breese Jr E C Ihemelandu 《Canadian journal of veterinary research》1976,40(3):276-284
The causative agent of stomatitis pneumoenteritis complex was isolated in domesticated goats and Vero cell culture. It was identified immunologically and morphologically as identical with the "Peste des Petits Ruminants" virus. There were cross reactions between stomatitis pneumoenteritis complex virus isolate and rinderpest virus by immunodiffusion and complement fixation tests but no cross neutralization. Goats recovered from stomatitis pneumoenteritis complex were protected against a challenge with rinderpest virus that was lethal to control goats. Ultrastructural morphology revealed intracytoplasmic and intranuclear inclusions made up of random arrays of fibrillar strands. Pleomorphic particles budded from the plasma membrane of infected cells and enveloped virions were seen extracellularly. Specific ferritin tagging was demonstrated in the stomatitis pneumoenteritis complex virus infected cells treated with homologous and peste des petits ruminants viral antibody systems but little, if any, tagging in the heterologous rinderpest system. 相似文献
913.
914.
E. E. SCHWEIZER 《Weed Research》1976,16(1):37-42
Persistence of ethofumesate [(±)2-ethoxy-2.3-dihydro-3,3-dimethylbenzofuran-5-yl-methansulphonate] in soil was associated with soil temperature. Ethofumesate applied at 4.5 kg/ha in November persisted about twice as long in soil as that applied the following March. In another field study, 88–91% of the herbicide had dissipated after 24 weeks in sandy loam soil, compared to 72–77% in loam soil when it was applied at rates of 2.2, 3.4, 4.5, and 9.0 kg/ha. The rate of degradation was independent of the initial rate of chemical applied. The time required for 50% of the herbicide to dissipate in sandy loam and loam soils was 7.7 and 12.6 weeks, respectively. The movement of ethofumesate in these two soils over a 24-weeks sampling period was confined mainly to the upper 7.5 cm of the soil profile. 相似文献
915.
The interaction of phosphine with purified cytochrome c and cytochrome oxidase was studied by absorption and circular dichroic spectrometry. Treatment of cytochrome oxidase with phosphine yielded absorption spectra in both the visible and Soret region that were similar to that produced by dithionite. Striking changes in the circular dichroic spectra were also recorded, sugesting that a valence change of the heme iron was accompanied by a conformation change of the prosthetic group.Phosphine treatment of cytochrome c also yielded spectra similar to those produced by reduction with dithionite suggesting a valence change of the heme iron. However, both the time necessary for complete reduction and the concentration of phosphine necessary for this effect suggest that, in comparison with cytochrome oxidase, cytochrome c was relatively insensitive. Reduction of cytochrome oxidase by phosphine had only a very minor effect on the intrinsic dichroic spectrum suggesting little effect on the polypeptide chains.The persistence of a component after reduction by phosphine and the subsequent reduction of this component by dithionite suggests that phosphine primarily reduced only one comonent of the cytochrome aa3 complex. The failure of EDTA and fluoride, which are known ligands of cytochrome a3 to affect the reduction of cytochrome aa3 by phosphine, as well as the occurrence of a 436-nm isosbestic point of the ferric-ferrous absorption spectra suggests that phosphine reduced primarily cytochrome a. However, it is argued that a slow reduction of cytochrome a3 cannot be ruled out. 相似文献
916.
Through the use of a critical electrolyte concentration staining technique, the glycosaminoglycans (GAGs) in the nucleus pulposus region of the canine intervertebral disc were arbitrarily identified as "hyaluronic acid", chondroitin sulphate and keratan sulphate. Approximate estimates of GAG concentration could be qualitatively deduced by determining the appropriate GAG "ALCIANOPHILIC INDEX". This index was considered to be an effective qualitative adjunct to chemical quantitation of GAGs in the intervertebral disc. 相似文献
917.
A new syndrome, characterised by acute respiratory distress and by abnormalities of the skin, hair and thyroid, was the apparent cause of neonatal death in 35 (24 per cent) of 146 piglets sired by a large white boar in four small commercial pig units. The syndrome appears to be of genetic origin, inherited as an autosomal recessive trait. Its similarities with the respiratory distress syndrome (RDS) of the newborn infant and the "barker" syndrome of the newborn foal are discussed. 相似文献
918.
919.
920.
The spectral interactions of 45 insecticide synergists and related compounds with oxidized and reduced cytochrome P-450 from microsomes of insecticide-resistant and -susceptible house flies were investigated. The type III interaction typical of piperonyl butoxide was the most common spectral interaction for the compounds studied. In addition to this, several other varients of the type III interaction were noted. In general these responses with house fly microsomes were similar to those reported for mammals, although some minor species and strain differences were observed. The cytochrome P-450 from susceptible house flies, although reported previously not to exhibit type I difference spectra with many xenobiotics, was found to elicit this spectral response with several methylenedioxyphenyl compounds. 相似文献