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131.
MICHAEL D. WHITACRE DVM MS Diplomate ACT LLOYD P. TATE VMD Diplomate ACVS CHARLES T. ESTILL VMD Diplomate ACT STEVEN D. VAN CAMP DVM Diplomate ACT 《Veterinary surgery : VS》1991,20(4):257-259
A vaginal septum was diagnosed in an English bulldog bitch during routine estrous cycle staging. The septum extended 16 cm from the vestibulo-vaginal junction to just caudal to the cervix. The septum was removed by two applications of an Nd:YAG laser via a flexible fiberoptic endoscope. Complete healing occurred over a 5-week period and was uneventful. The bitch was bred and subsequently delivered four puppies vaginally. Transendoscopic laser ablation provided a noninvasive approach to surgically remove a vaginal septum in the dog. 相似文献
132.
Resistance in apple is evaluated by needle–inoculation of succulent shoot tips with 106–107 cells of a virulent isolate of Erwinia amylovora (Burr.) Winslow et al. (the incitant of fireblight) and measurement of the resulting cortical lesion when extension is complete. Data are now available on practically all commercial cultivars, some of which have a useful level of resistance. Some newer cultivars, particularly those with resistance to scab (Venluria inaequalis [Cooke] Wint.) derived from Malus floribunda, have good resistance to E. amylovora. A very high level of resistance is present in Asiatic Malus species, including M. x robusta, M. x sublo–bata, M. x atrosanguinea, and M. prunifolia, and in the North American species M. fusca. This type of resistance appears to be inherited polygenically, and because of its detectability in young seedlings can be used conveniently in breeding. Objectives of pear breeding programs are aimed at developing superior fruit quality combined with resistance to fireblight, psylla, and Fabraea leaf spot. Many high quality cultivars of Pyrus communis are extremely susceptible to E. amylovora and sensitivity appears to be controlled by a dominant gene Se. A high level of resistance is present in P. ussuriensis but varies considerably between clonal selections of other Pyrus species. Pear seedlings from controlled pollinations are artificially inoculated in the glasshouse with a similar bacterial suspension as used for apples, and only the most resistant ones are selected and planted in the field for future evaluation. In Beltsville, heritability studies of crosses between non–sensitive parents have indicated that selection for resistance within progenies results in a high degree of genetic gain. Interspecific hybridization has an advantage over P. communis crosses mainly when insect or fungus resistance is required. 相似文献
133.
The intra-uterine position of canine foetuses and their sequence of expulsion at birth 总被引:1,自引:0,他引:1
G. C. VAN DER WEYDEN M. A. M. TAVERNE A. C. OKKENS P. FONTIJNE 《The Journal of small animal practice》1981,22(8):503-510
In 14 bitches, laparotomy was performed between the 45th day and 54th day of gestation. In total, 89 foetuses were marked individually by means of transuterine injections of a radiopaque substance. After expulsion, each pup was provided with a colour code. By radiographs one day after birth, all pups of a litter could be identified by the radiopaque markings. In this way the order and presentation at birth of each pup could be compared with the uterine position and presentation at laparotomy. When after expulsion of a pup, one or more were left in each uterine horn, the next pup was produced by the contralateral horn in 43 cases (78·2%) and by the ipsilateral horn in 12 cases (21·8%). One horn was never observed to be completely empty before the other horn started expelling pups. In six of eight bitches in which each two uterine horns did not contain an equal number of foetuses, the first pup was born from the horn containing most pups. The presentation at birth has been observed in 73 pups. For five of these (6·9%), the presentation differed from the one observed at laparotomy; in all five cases the original posterior presentation had changed into an anterior one. 相似文献
134.
Influence of organic material and soil moisture content on the adsorption of aniline Adsorption of aniline is directly related to the organic content of the soil and appears to depend mainly on the humic acid content. The competitive effect of soil water in the adsorption of aniline was examined. The influence of colloidal suspensions on adsorption was such that in natural surroundings only trace quantities of aniline were found in soil liquid. In every case, desorption was accompanied by a pronounced hysteresis effect, but salt solutions (CaCl2) had the greatest ability to displace adsorbed aniline. 相似文献
135.
136.
Marked increases in sweating rate occurred within 1.5 seconds after the initiation of muscular activity in a warm room. This increase did not seem dependent upon thermal stimuli, but was related to the work rate, and the ambient temperature, or the sweating rate during the pre-exercise perhiod. 相似文献
137.
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139.
应用酶联免疫吸附试验(Enzyme linked immunosorbent assay,ELISA)对在2011年间采自西藏(988份)、青海(475份)和四川(377份)共1840份牦牛血清样品进行牛传染性鼻气管炎病毒抗体检测。结果检出阳性血清样品西藏381份,阳性率38.6%;青海212份,阳性率为44.6%;四川105份,阳性率为27.9%。结果表明,中国西部高原西藏、青海以及四川牦牛群中均存在牛传染性鼻气管炎病毒的感染。本研究调查了牛传染性鼻气管炎在中国西部高原牦牛群中的流行情况,为制定该病的防治措施提供理论依据。 相似文献
140.
VAN Schmus WR 《Science (New York, N.Y.)》1986,231(4739):751-752