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41.
42.
A ten-year-old female poodle was presented for left hindlimb lameness. Radiographically, irregular intramedullary densities of long bones (bone infarcts) and a lytic lesion in the left distal femur were detected. Two years after the first examination, the lesions in the distal femur were definitely identified as osteosarcoma and the dog was euthanized. Pathological and histological changes of the bone infarcts as well as of the osteosarcoma are described. Regarding bibliographical data, occurrence and aetiopathogenesis of osteosarcoma associated with multifocal bone infarction in man and dog are discussed. 相似文献
43.
44.
With the help of a new synthetic material follicles and corpora lutea from the ovaries of 80 cows in different stages of the sexual cycle were examined for modifications of their blood vessel architecture. In the theca externa the main artery which runs towards the follicle, separates into arterioles of which capillaries derive in the theca interna, building a basket-like network around the zona granulosa. After ovulation the follicle wall forms characteristic fields. Capillaries grow into the zona granulosa and thus the folds form the lobular structure of the corpus luteum. Capillaries which rise from the ruptured part of the follicle, spread centripetally and together with lutein cells they build up the not lobulated cupola of the corpus luteum. The regression of the corpus luteum starts around the 16th day of the cycle, beginning at the capillary network of the cupola. A contraction of the vessels and a quick decrease of the volume follow. 相似文献
45.
陕西蚕病流行规律分析 总被引:1,自引:1,他引:0
通过历年盒种产茧量、干茧病蛹及蚕期蚕病调查,得知养蚕技术、养蚕形式、地理位置、气候条件影响陕西蚕病的流行分布。近几年危害生产的主要是僵病、多角体病及微粒子病。各地由于养蚕形式、技术、地理及气候差异,蚕病发生轻重不同。僵病流行比其它蚕病受养蚕技术、地理、气候影响更明显。多角体病流行与僵病不同,有较明显的垂直传播特点。微粒子病自1989年发现之后,蔓延迅速,其病原首先来自从疫区调入的带毒蚕种。 相似文献
46.
Two cases of H.c.c. which occurred in winter 1987 in Vienna are described. Case one was a female Chow-Chow, 8 weeks of age, that died from the peracute form of the disease. The diagnosis was confirmed by histology and direct immunofluorescence. Case two, a 9-month old female Kuvacz, showed clinical signs of the subacute form of H.c.c. She was hospitalized and therapy was successful. The disease was diagnosed by the typical clinical signs and the raise of antibodies in paired serum samples. Etiology, clinical signs and immunology of H.c.c. are discussed. 相似文献
47.
R D Park 《Veterinary Clinics of North America: Equine Practice》1989,5(1):47-66
A complete radiographic examination of the equine foot consists of properly exposed, processed, and positioned radiographs. For radiographic interpretation, in addition to knowing radiographic signs of disease, a knowledge of normal radiographic anatomy and possible insignificant anatomic variations is necessary. 相似文献
48.
49.
The kidney's microvascularization of the Pudu pudu is mostly similar to that of domestic animals. The renal parenchymatous arteries do not give off capsular branches. The majority of the Pudu pudu's glomerula shows spherical shape. Glomerula next to the medulla have a diameter which is an average of 25 microns larger than the diameter of those situated more peripherally. Their volume is comparable to that of the angora rabbit. The capillaries form anastomosis in the inner and outer part of the glomerulus. 相似文献
50.
把电流模式电路引进了神经网络理论,提出了一种用电流模式电路构成的神经网络阈值处理单元,并由此构成了电流模式Hopfield神经网络,此网络中信号都是以电流的形式出现的。 相似文献