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11.
Two aged dogs with chronic obstructive airway disease were evaluated because of intermittent swelling of the ventral cervical region. Radiographs made at expiration and caudal positioning of the forelimbs allowed identification of intermittent cervical lung herniation of the left and right cranial lung lobe in both dogs. Pulmonary hyperinflation, increased expiratory effort, and chronic coughing were considered responsible for the lung herniation. Cervical lung hernia should be included in the differential diagnoses of intermittent cervical swelling in dogs with chronic respiratory disorders associated with increased expiratory effort and chronic coughing.  相似文献   
12.
We characterized the pattern of ultrasonographic contrast enhancement of the small intestinal wall using a commercial contrast medium (Sonovue®) in 10 healthy awake cats. Subjectively, a rapid intense enhancement of the serosal and submucosal layers was followed by gradual enhancement of the entire wall section during the early phase. At peak enhancement, there was a subjective loss of demarcation between intestinal wall layers. In the late phase, there was a gradual wash out of signal from the intestinal wall. Submucosal wash out occurred last. Time‐intensity curves were generated for selected regions in the intestinal wall and multiple perfusion parameters were calculated for each cat. Perfusion parameters included arrival time (7.64 ± 2.23 s), baseline intensity (1.04 ± 0.04 a.u.), time to peak from injection (10.74 ± 2.08 s), time to peak from initial rise (3.1 ± 1.15), peak intensity (8.92 ± 3.72 a.u.), wash‐in rate (2.06 ± 0.70 a.u./s) and wash‐out rate (?1.07 ± 0.91 a.u./s). The perfusion pattern of normal feline small bowel may be useful for characterizing feline gastrointestinal disorders that involve the intestinal wall.  相似文献   
13.
In 1997 the government of Hong Kong reformed its policy on the language medium for teaching at the secondary‐school level and removed schools' right to choose their own medium. Among the 404 public and “aided” secondary schools in Hong Kong, the government allowed only 100 to use English as the medium for teaching and required the remaining 304 to use the native language, Chinese. The authors assess the spatial impact of the policy reform and estimate the bid function for English‐language schools. The results show that the 1997 policy reform shifted parental preferences from public to private education and increased the marginal bid for proximity to private English schools by 2 percent. Following the reform, homeowners were willing to pay, on average, HK $8,400 for each additional 100 metres closer to a private English school.  相似文献   
14.
凡纳滨对虾池塘水质及对虾肌肉品质的对比分析   总被引:6,自引:2,他引:6  
2010年5-9月期间,对上海奉贤区两个养殖场采取不同养殖方式的22个凡纳滨对虾养殖塘的水温(T)、总溶解盐(TDS)、溶解氧(DO)、pH、透明度(SD)、亚硝酸盐氮(NO2 N)、总氨氮(TAN)、硝酸盐氮(NO3N)、总氮(TN)、活性磷(PO4P)、总磷(TP)、叶绿素a(Chl.a)、五日生化需氧量(BOD5)等因子进行监测,其中1号场养殖用水为经沉淀处理的天然河水,而2号场则为添加了海水晶的河水。结果表明:试验期间水体的温度、DO、pH变化幅度不大,基本可满足凡纳滨对虾生长的条件;总体上硝酸盐氮(NO3N)在无机氮(TIN)中所占比例最高,总氨氮(TAN)在TIN中所占比例随养殖周期的推延而增加,养殖后期NO2N所占比例升高趋势明显;活性磷含量则逐渐下降,总磷逐渐升高; BOD5、叶绿素a的含量随时间延长而逐渐上升。测定了两个养殖场成虾的肌肉品质结果如下:1号场南美白对虾肌肉的粗蛋白和粗脂肪含量分别为16.30%和1.42%,低于2号场的18.30%和1.61%;1号场成虾氨基酸总量为23.27%,其中必需氨基酸含量为9.09%,而2号场则分别为27.52%和10.74%;在鲜味氨基酸方面,1号、2号养殖场的含量分别为 8.52%和10.16%。  相似文献   
15.
Benign gastric polyps are uncommon in dogs and most are discovered incidentally. Polyps protruding into the pyloric antrum can cause gastric outflow obstruction. Clinical and ultrasonographic findings in seven dogs with histologically confirmed benign mucosal gastric polyps were reviewed. Sonographic findings such as shape, size, echogenicity, location, evidence of gastric wall thickening, wall layering, and size of regional lymph nodes were recorded. Five sessile and two pedunculated masses of different sizes (range 7–60 mm) and echogenicities were found. They primarily arose from the mucosal layer and protruded into the gastric lumen. Only one dog had a large inhomogeneous mass with a poorly visualized gastric wall layering. The polyps were all single, and were located in the pyloric antrum in six out of seven dogs. Although the ultrasonographic appearance allowed a presumptive diagnosis of mucosal gastric polyp, the final diagnosis was determined from histopathologic examination.  相似文献   
16.
17.
Certain magnetic resonance (MR) enhancement patterns are often considered to be associated with a specific diagnosis but experience shows that this association is not always consistent. Therefore, it is not clear how reliably contrast enhancement patterns correlate with specific tissue changes. We investigated the detailed histomorphologic findings of intracranial lesions in relation to Gadodiamide contrast enhancement in 55 lesions from 55 patients, nine cats, and 46 dogs. Lesions were divided into areas according to their contrast enhancement; therefore 81 areas resulted from the 55 lesions which were directly compared with histopathology. In 40 of 55 lesions (73%), the histomorphologic features explained the contrast enhancement pattern. In particular, vascular proliferation and dilated vessels occurred significantly more often in areas with enhancement than in areas without enhancement (P=0.044). In 15 lesions, there was no association between MR images and histologic findings. In particular, contrast enhancement was found within necrotic areas (10 areas) and ring enhancement was seen in lesions without central necrosis (five lesions). These findings imply that necrosis cannot be differentiated reliably from viable tissue based on postcontrast images. Diffusion of contrast medium within lesions and time delays after contrast medium administration probably play important roles in the presence and patterns of contrast enhancement. Thus, histologic features of lesions cannot be predicted solely by contrast enhancement patterns.  相似文献   
18.
We describe the ultrasonographic diagnosis of diplomyelia in a 40‐day‐old calf. The acoustic window was the lumbosacral junction, which, in cattle, corresponds to the L6–S1 intervertebral space and enables the evaluation of approximately 1 cm of the length of the spinal cord. Despite this limited length, this acoustic window yields good anatomic details and can be helpful in assessing anomalies of the caudal aspect of the spinal cord.  相似文献   
19.
The virulences of 102 single-zoospore cultures of Phytophthora fragariae from one field site were determined on a range of strawberry differentials, and used to assign the cultures to four clusters (I, II A, IIB, IIC) using cluster analysis. On cv. Favourite, which is susceptible to all known races of the pathogen, isolates in cluster I were recovered most frequently and had the narrowest spectrum of virulence. On cv. Saladin isolates in cluster IIB were more common and were pathogenic to this cultivar. However, c. 30% of the single zoospores from field isolates from Saladin were avirulent on this cultivar and belonged to cluster I. Hyphal-tip and single-zoospore cultures from selected field isolates in cluster IIB did not always have the same virulence phenotype as the parent isolates. One hyphal-tip culture from a field isolate in cluster IIB had a virulence phenotype (IID) which had not been recorded before in Europe, and it attacked some cultivars not previously affected by red core. When cultivars such as Saladin were inoculated with mixtures of zoospores from two isolates from different clusters, with and without the corresponding virulence factors, the isolate with the corresponding virulence factor was selected. However, on the universally susceptible cv. Favourite the results depended on the relative competitiveness of the isolates and not on virulence factors.  相似文献   
20.
Phytophthora syringae, P. drechsleri, P. cactarutn, P. cambiuora and P. megasperma were isolated from the roots of red raspberry plants affected by severe root and crown rot with associated cane death. Phytophthora megasperma occurred most frequently and consisted of two types of isolates which differed in colony morphology, growth rates, and oogonial, oospore, sporangial and zoospore size, and pathogenicity to a range of plants. One type with large oospores was typical of P. megasperma var. megasperma , and was non-pathogenic to red raspberries, while the other with smaller oospores and which grew more slowly in culture than the first, was highly pathogenic, producing symptoms similar to those observed in the field. Highly pathogenic isolates from Germany and the USA were of this type.
All red and black raspberry cultivars tested were susceptible to the pathogenic type, although North American cultivars were generally less affected than British ones. Inoculated plants had reduced shoot and root weights, stem lesions and wilted and yellowed leaves. The blackberry × raspberry hybrid Tayberry and its blackberry parent were immune.
Phytophthora drechsleri, P. cactorum and P. cambivora produced small to moderate amounts of root rot on red raspberry, and P. cambivora also caused slight symptoms on shoots.  相似文献   
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