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991.
A dog with aspiration pneumonia was examined by computed tomography (CT) with 8-mm continuous scans of the chest. The results demonstrated that CT is a useful procedure for evaluating pneumonia, although high cost prevents its routine use. A normal littermate was examined, and normal structures of the chest and chest wall were compared.  相似文献   
992.
以北碚东阳黄马牙辐照诱变后代095为母本,自330为父本配制选育成西农单交一号中熟玉米,在四川省平丘组区域试验中,平均产6068.7kg/ha,比对照种中单二号增产10.2%,增产点达83%以上。其籽粒含粗脂肪5.32%,粗蛋白10.57%。赖氨酸0.30%,已在四川、云南、贵州、广西等省推广。  相似文献   
993.
<正> The main objective of the present research was to determine the influence of gamma irradiations on wheat,the diet of the grain weevil,using as parameters of the longevity and reproduction of this insect.The doses of 60Coγ-rays applied to wheat grains were O(control),125,250,500,1000,2000,and 4000 Gy,at a dose rate of 3000 Gy per hour.The longevity,expressed as life-expectancy in days,and the reproduction expressed as the number of F1 adults,showed no differences up to the dose of 2000 Gy.The wheat irradiated with the dose of 4000 Gy induced a lower life-expectancy of the insects fed with irradiated wheat and a smaller number of insects of the F1 generation.  相似文献   
994.
Caudal cervical spondylomyelopathy is a common neurologic disorder of Doberman pinschers which has a number of striking similarities to cervical spondylotic myelopathy in humans. Diagnosis of this human disease is facilitated considerably by the use of computed tomographic (CT) myelography. Sixteen Doberman pinscher dogs with caudal cervical spondylomyelopathy were studied by conventional myelography followed by CT myelography. A close correlation was noted between the CT myelographic appearance of the cervical spinal cord in these dogs, and that reported for human cervical spondylotic myelopathy. Five dogs had atrophy of the spinal cord, and in another there was an accumulation of contrast medium within the spinal cord. These features are often associated with a poor response to surgical decompression in humans with cervical spondylotic myelopathy. The CT examination provided information that could not be obtained by conventional myelography alone and should be considered as an additional diagnostic procedure in dogs with caudal cervical spondylomyelopathy.  相似文献   
995.
This retrospective analysis of 15 dogs with postcontrast ring enhancing brain lesions, each detected by a single Computed Tomography [CT] examination, searched for any association between their CT appearance and the pathologic diagnosis. In a subgroup of these dogs [n = 7] necropsied within 2 days of the last CT scan, we evaluated whether there was any anatomic correlation between the ring zone and the histopathologic features of the lesions. Our study consisted of eight dogs with primary brain tumors [3 meningiomas, 3 astrocytomas, 1 mixed glioma, 1 oligodendroglioma], 4 with metastatic brain tumors [2 fibrosarcomas, 1 mammary carcinoma, 1 melanoma] and 3 with non-neoplastic brain lesions [2 intraparenchymal hemorrhages, 1 pyogranulomatous meningoencephalitis]. The overall size and shape of the contrast enhancing CT lesions, as well as the thickness, surface texture and degree of enhancement of the ring were subjectively evaluated. No association was found between the CT lesion characteristics and the pathologic diagnosis. In the sub-group of dogs euthanatized within 2 days of the CT examination, distinct histologic features which anatomically correlated with the zone of ring enhancement were found in 3 of 7 lesions. The findings of this study are consistent with those of ring-enhancing lesions in people, and indicates that CT ring enhancement is a non-specific phenomenon which can occur in a variety of neoplastic and non-neoplastic lesions in the dog.  相似文献   
996.
997.
Increasingly severe degrees of pneumothorax were produced in 6 adult anesthetized bloodhounds. Computed tomography (CT) of the thorax was performed on each dog to evaluate the effects of pneumo thorax on thoracic and on pulmonary cross-sectional area (TA and PA). Arterial PO2 (PaO2) and PCO2 (PaCO2), heart rate (HR), and mean arterial blood pressure (MAP) were determined and related to the severity of pneumothorax. Volumes of air equal to 1, 1.5 and 2 times functional residual capacity of the lung produced approximately 33%, 40%, and 50% reductions in pulmonary area respectively. These amounts of atelectasis correspond to a radiographically "moderate" degree of pneumothorax. As severity of pneumothorax increased, thoracic area consistently increased, PaO2 consistently decreased, and PaCO2 consistently increased, with all being statistically significant relationships (p<0.0001); but HR and MAP were variable and showed no statistical correlation to the degree of pneumothorax (p>0.2).  相似文献   
998.
The purpose of this study was to produce a comprehensive anatomic atlas of CT anatomy of the dog for use by veterinary radiologists, clinicians, and surgeons. Whole-body CT images of two mature beagle dogs were made with the dogs supported in sternal recumbency and using a slice thickness of 13 mm. At the end of the CT session, each dog was euthanized, and while carefully maintaining the same position, the body was frozen. The body was then sectioned at 13-mm intervals, with the cuts matched as closely as possible to the CT slices. The frozen sections were cleaned, photographed, and radiographed using xeroradiography. Each CT image was studied and compared with its corresponding xeroradiograph and anatomic section to assist in the accurate identification of specific structures. Clinically relevant anatomic structures were identified and labeled in the three corresponding photographs (CT image, xeroradiograph, and anatomic section). In previous papers, the head and neck, and the thorax and cranial abdomen of the mesaticephalic (beagle) dog were presented. In this paper, the caudal part of the abdomen and pelvis of the bitch and male dog are presented.  相似文献   
999.
In the last 21/2 years, 288 grey parrot and amazon species with symptoms of respiratory disease clinically were presented to the clinic for avian medicine at the Justus-Liebig-University in Giessen. Ventro-dorsal and latero-lateral radiographs were taken from all birds; radiologic signs of lower respiratory tract disease were noted. Radiographs were normal in 55 of the birds. The results of the radiographic examination for the remaining 233 birds were compared with the necropsy results of terminally ill parrots, with the results of laboratory examinations/endoscopy/and/or with an examination by computed tomography. Thoracic radiographs were evaluated for occurring radiological abnormalities pertaining to the respiratory tract. The frequency of these lesions and their association with a disease process and/or specific etiology was noted.  相似文献   
1000.
本文采用标定航空像片样地新方法,解决了像主点落水或选刺像主点困难的难题。此法效率高,点位精度好,用单张像片标定样地,避免了立体观察辐射交会;同时在检查样地时,容易判定移位原因,便于纠正。因此,在千岛湖地区的调查研究中,此法显得简便、易行,是效率高的好方法。  相似文献   
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