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排序方式: 共有514条查询结果,搜索用时 15 毫秒
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IMC10200株ALV-J实验诱发禽骨髓性白血病的研究 总被引:2,自引:0,他引:2
对分离自肉种鸡群亚临床感染的J亚群禽白血病病毒IMC1o200株进行了实验感染诱发禽骨髓性白血病的病理学研究.IMC10200株J亚群禽白血病病毒尿囊腔接种11日龄肉鸡胚和SPF蛋鸡胚,孵出后跟踪观察.9周龄时随机抽检感染鸡,感染肉鸡特异引物PCR检测全部为阳性;组织病理学观察感染鸡无明显病变.至21周龄时感染肉鸡出现第一例典型骨髓性白血病病例;感染SPF蛋鸡未见明显J亚群禽白血病相关病变. 相似文献
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《Veterinary immunology and immunopathology》2015,163(1-2):16-22
Diagnosis of chronic progressive lymphoedema (CPL) in draught horses, including the Belgian Draught Horse, is mainly based on clinical evaluation of typical lower limb lesions. A deficient perilymphatic elastic support, caused by a pathological elastin degradation in skin and subcutis, has been suggested as a contributing factor for CPL. Elastin degradation products induce the generation of anti-elastin Ab (AEAb), detectable in horse serum by ELISA. For a clinically healthy group of draught horses, a significantly lower average AEAb-level than 3 clinically affected groups (mild, moderate and severe symptoms) was demonstrated previously. To improve CPL-diagnosis, we evaluated the AEAb-ELISA as an in vitro diagnostic aid in individual horses. Test reproducibility was assessed, performing assays independently in 2 laboratories on a total of 345 horses. Possible factors associated with AEAb-levels (age, gender, pregnancy, test lab and date of blood collection) were analyzed using a mixed statistical model. Results were reproducible in both laboratories. AEAb-levels in moderately and severely affected horses were significantly higher than in healthy horses. Nevertheless, this was only demonstrated in barren mares, and, there was a very large overlap between the clinical groups. Consequently, even when a high AEAb cut-off was handled to obtain a reasonable specificity of 90%, a very low sensitivity (21%) of AEAb for CPL-diagnosis was obtained. Results on the present sample demonstrate that the described ELISA procedure is of no use as a diagnostic test for CPL in individual horses. 相似文献
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Rémi Froment Christian Bédard 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2016,45(3):459-465
This is the report of a 5‐year‐old male neutered Great Dane with an extreme leukocytosis (544.9 × 109 cells/L; RI 5.2–13.9 × 109 cells/L) characterized by highly atypical round cells. Cellular morphologic features such as cytoplasmic membrane blebs, a high nuclear‐to‐cytoplasmic ratio, and nuclear indentations and irregularities and large nucleoli, as well as immunocytochemistry for CD3 and CD79, myeloperoxidase cytochemistry, and clonality testing were not conclusive for myeloid or lymphoid origin. Marked alkaline hyperphosphatasemia was present at the first visit (2783.0 U/L; RI 6–80.0 U/L), followed by a 5‐fold increase (14,000 U/L) a week later, identified as being mostly contributed by the bone‐ALP isoform (11,062 U/L; RI 0–30 U/L). In addition, the atypical leukocytes were strongly positive for cytoplasmic ALP activity. In vitro lysis of a heparin blood sample resulted in a 1.7‐fold increase of ALP activity, supporting the origin of the hyperphosphatasemia at least in part from the leukemic cell population. To the authors’ knowledge, this is a unique case of alkaline hyperphosphatasemia, due at least to a leukemic cell population producing a bone‐ALP isoform, regardless of the exact nature of the leukemia. 相似文献
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Hoffman AM Oura TJ Riedelberger KJ Mazan MR 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(1):184-192
BACKGROUND: Horses with recurrent airway obstruction (heaves) are described as exhibiting "increased abdominal effort," but it is unknown whether this translates to an effective contribution to ventilation. HYPOTHESIS: We hypothesized that heaves is characterized by asynchrony between rib cage and abdominal motions, and that the abdominal component is the major contributor to ventilation. ANIMALS: The rib cage versus abdominal motion in naturally occurring heaves (n = 15) was compared to controls at rest (n = 7) and during hyperpnea because of lobeline treatment, and the effects of histamine-induced bronchoconstriction in controls (n = 10). METHODS: Flow patterns, phase angle (theta) between the rib and abdominal compartments, abdominal (Vabd) contribution to tidal volume (VT), and lung mechanics were measured. RESULTS: Findings unique to the heaves group included the loss of biphasic expiratory flow, severely increased theta with the abdomen consistently lagging behind the rib cage, and a reduced contribution of the abdomen to ventilation. A subgroup of heaves (n = 5) with abdominal paradox showed a significant (P < .05) reduction in tidal volume, and increased respiratory rate. Bronchodilation reduced theta in heaves (P = .06), but theta remained significantly higher after bronchodilation than found in controls. CONCLUSIONS AND CLINICAL IMPORTANCE: We conclude that breathing pattern in horses with heaves is characterized by severe rib cage/abdominal asynchrony, with the rib cage motion in synchrony with flow, therefore dominating ventilation. In a subset of heaves, the abdominal compartment (diaphragm, abdominal muscles) was completely out of synchrony with flow ("abdominal paradox") despite the clinical appearance of "increased abdominal effort." 相似文献
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AIM: To establish a method for obtaining specific cells in solid tumor tissue by sorting of CD11b+ myeloid cells in hepatic metastases from colorectal cancer.METHODS: Tumor tissues were prepared into single cell suspension by mechanical method combined with enzyme digestion, and then the CD11b+ myeloid cells were isolated by flow cytometry. The sorted cells were identified by immunocytochemistry. The viability and morphologiy of the sorted cells were evaluated by Giemsa and Typan blue staining. The cell purity was evaluated by flow cytometry.RESULTS: Sufficient numbers of CD11b+ cells with high purity were isolated by sorting with flow cytometry from the single cell suspension prepared by mechanical and enzyme digestion. The purity of the cells was confirmed by statistical analysis (P<0.05). The positive rates of the cells before and after sorting were significantly different (P<0.01). The positive cells were verified by immunocytochemical method. Meanwhile, the sorted cells had complete morphology and good activity.CONCLUSION: The CD11b+ myeloid cells in solid tumor tissue can be isolated by flow cytometry from the machine-enzyme digestion suspension with high purity, good activity and complete morphology. 相似文献
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AIM: To evaluate specific metabolomics profiles in the serum of patients with chronic mountain sickness (CMS) and to explore the potential metabolic biomarkers in the native Tibetans living on the Qinghai-Tibet Pla-teau.METHODS: A gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) approach as a metabolomics technique was used to evaluate metabolic differences. The native Tibetan CMS patients (n=10) and healthy Tibetan controls (n=10) were enrolled from YuShu in Qinghai province in this study. The serum samples were collected and analyzed by GC-TOF-MS coupled with a series of multivariate statistical analyses such as principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA) and orthogonal partial least squares discriminant analysis (OPLS-DA).RESULTS: The intergroup differences between CMS patients and control subjects have been observed. A list of differential metabolites and several top altered metabolic pathways have been identified. The levels of fumaric acid, an intermediate in the tricarboxylic acid (TCA) cycle, and inosine were highly upregulated in the CMS patients, suggesting a greater effort to hypoxic adaptation in high elevation area. Other differential metabolites, such as methyl phosphate, 2-ketoadipate, lyxose and phytanic acid were also identified. Importantly, the differential metabolites possessed higher area under the ROC curve (AUC) values, indicating an excellent clinical ability for the prediction of CMS. Increased levels of amino acids (isoleucine, glycine, serine, L-cysteine, citrulline and trimethyllysine) were detected in CMS group, yet significantly decreased levels of sulfuric acid, oxamic acid, lyxose and glutamine were also detected in CMS group than those in control group. At the same time, the levels of ribose and glucose-1-phosphate were markedly elevated in CMS group (P<0.05).CONCLUSION: The metabolic activities are significantly altered in the serum of CMS patients. High altitude hypoxia may act on the disturbed glucose metabolism and amino acid metabolism in part of the Tibetan triggered by CMS. 相似文献