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101.
Abstract: A 1‐year‐old intact female miniature Dachshund was presented with hematochezia, vomiting, and diarrhea of more than 1‐week duration. An abdominal mass was palpated, which at exploratory surgery was found to be a 7‐cm‐long thickened section of ileum. The thickened ileum was resected. Impression smears revealed numerous small‐ to medium‐sized lymphocytes, with a smaller number of cells resembling Mott cells. The Mott‐like cells contained multiple pale vacuoles that were positive for periodic acid‐Schiff (PAS) in wet‐fixed smears, consistent with Russell bodies. Histologic evaluation of the surgically excised ileum revealed 2 populations of neoplastic lymphoid cells. The majority were uniform medium‐sized lymphocytes with hyperchromatic oval or round nuclei and inconspicuous nucleoli. The remaining cells resembled Mott cells, which contained several PAS‐positive eosinophilic globules in the cytoplasm, occasionally compressing the nucleus. The majority of neoplastic cells stained positively for vimentin, CD20, CD79a, and Pax‐5, but were negative for CD3 and lysozyme; 43.5% of cells stained positively for Ki‐67. The Mott cells were strongly positive for immunoglobulin but were negative for Pax‐5. Using electron microscopy, a homogenous substance of intermediate electron density was observed frequently in the cisternae of rough endoplasmic reticulum in the cytoplasm of the Mott cells, and rarely in the perinuclear cisternae of the lymphoid cells, corresponding to the site of immunoglobulin staining. Monoclonal rearrangement of immunoglobulin heavy‐chain (IgH) gene was observed by PCR testing for lymphocyte–antigen receptor rearrangement. The morphologic features, immunophenotype, and IgH gene rearrangement verified the lymphoid cells were neoplastic (mature cell type) and had a B‐cell phenotype, with evidence of immunoglobulin production and differentiation into Mott cells. This case was unusual because of the age of the dog and because most intestinal lymphomas are T‐cell phenotype. The Mott cell morphology also differed from typical mature B‐cell lymphoma types and may be a unique B‐cell lymphoma variant.  相似文献   
102.
103.
Objective : To investigate the association between synthetic colloids and biomarkers of acute kidney injury (AKI) in dogs with hemorrhagic shock. Design : Experimental interventional study. Setting : University. Animals : Twenty‐four healthy ex‐racing Greyhounds. Interventions : Anesthetized Greyhounds subjected to hemorrhage for 60 min were resuscitated with 20 mL/kg of fresh whole blood (FWB), 6% hydroxyethyl starch (HES) 130/0.4, 4% succinylated gelatin (GELO), or 80 mL/kg of isotonic crystalloid (CRYST) over 20 min (n = 6 per treatment). Concentrations of biomarkers of AKI were measured at baseline, end of hemorrhage, and at 40 (T60), 100 (T120), and 160 (T180) min after fluid bolus. Biomarkers included neutrophil gelatinase‐associated lipocalin in urine and serum (uNGAL; sNGAL), and urine cystatin C (uCYSC), kidney injury molecule‐1 (uKIM), clusterin (uCLUST), osteopontin, gamma‐glutamyl transferase, monocyte chemoattractant protein‐1 (uMCP), interleukin‐6, interleukin‐8, protein (uPROT), hyaluronan, and F2‐isoprostanes. Renal histology was scored for tubular injury and microvesiculation. Biomarker fold‐change from baseline was compared between groups using mixed effects models (Bonferroni–Holm corrected P<0.05). Frequencies of histology scores were compared by Fisher's exact test. Measurements and main results : In dogs treated with GELO, uNGAL fold‐change was markedly greater compared with all other groups at T60, T120, and T180 (all P<0.001), and uCYSC was greater at T60 compared with CRYST (P<0.001), and at T120 and T180 compared with all other groups (all P<0.001). Smaller, albeit significant, between‐group differences in uKIM, uCLUST, uMCP, and urine protein concentration were observed across the FWB, GELO, and HES groups, compared with CRYST. The GELO group more frequently had marked tubular microvesiculation than the other groups (P = 0.015) although tubular injury scores were comparable. Conclusion : In dogs with hemorrhagic shock, GELO was associated with greater magnitude increases in urine biomarkers of AKI and more frequent marked tubular microvesiculation, compared with FWB, CRYST, and HES.  相似文献   
104.
The prevalence of cancer in animals has increased significantly over the years. Mammary tumours are the most common neoplasia in dogs, in which around 50% are presented in the malignant form. Hence, the development and characterization of in vitro models for the study of canine tumours are important for the improvement of cancer diagnosis and treatment. Thus, the aim of this study was to characterize cell lines derived from canine mammary gland neoplasias which could be further used for basic and applied oncology research. Samples of canine mammary carcinomas were taken for cell culture and 2 cell lines were established and characterized in terms of cell morphology, tumourigenicity and global gene expression. Both cell lines presented spindle‐shape morphology and shown common malignant features as in vitro invasion potential and expression of epithelial and mesenchymal proteins. Also, we found gene expression patterns between the 2 cell cultures in comparison to the normal mammary gland tissue. Cells from M25 culture showed a higher invasion and in vivo tumourigenic potential, associated to the overexpression of genes involved in focal adhesion and extracellular matrix communication, such as FN1, ITGA8 and THBS2. The phenotypic characterization of these cells along with their global gene expression profile potentially determine new therapeutic targets for mammary tumours.  相似文献   
105.
The spatial distribution patterns of the attack on fresh logs ofPasania edulis was studied for the oak borer,Platypus quercivorus (Murayama), and two species of Scolytid ambrosia beetles,Xylosandrus crassiusculus (Motschulsky) andXyleborus attenuatus Blanford, in 1994 and 1995. On the logs where onlyP. quercivorus attacked, the entry holes were distributed uniformly when attack intensity was low. However, the distribution pattern became more aggregated with the increase in attack intensity. On logs where bothP. quercivorus and the two Scolytid species attacked, there was a negative association between the spatial distribution of the entry holes ofP. quercivorus and that of scolytids. Simultaneous attack of two scolytids also increased the degree of aggregation of the entry holes ofP. quercivorus. The entry holes of scolytids were distributed in groups irrespective of the attack intensity of scolytids andP. quercivorus. These results suggest an asymmetrical interspecific relationship betweenP. quercivorus and scolytids. Concentration of the entry holes ofP. quercivorus in a small area may cause a considerable decline in the reproductive success in the galleries constructed there.  相似文献   
106.
The distributions of ectomycorrhizas and ectomycorrhizal fungal inoculum with soil depth (0–45 cm) were determined in a 40-year-oldBetula platyphylla var.japonica forest. Mycorrhizal and non-mycorrhizal fine roots were measured in each soil core sample that was collected at soil depths of 0–5, 5–10, 10–15, 15–20, 20–25, 30–35, and 40–45 cm. The ectomycorrhizas were mainly distributed (>50%) in the top soil (0–5 cm) of organic forest floor horizons. Below 5 cm the quantity of ectomycorrhizas decreased sharply. The percentage of fine roots which were ectomycorrhizal gradually declined with the depth of soil. The ectomycorrhizal fungal inoculum was evaluated by a bioassay method, measuring the lengths of the entire root system and of the ectomycorrhizal roots of birch seedlings planted in each soil sample. The soil samples were collected from 0–5, 10–15, 20–25, 30–35, and 40–45 cm depths of the soil profile. Ectomycorrhizal formation on birch seedling roots in the bioassay was high in both the soil depth intervals 0–5 cm and 10–15 cm, while the amount was lower in the soil depth interval from 20–45 cm. The results of these investigations show that the amount of the ectomycorrhizas in soil, and the ectomycorrhizal fungal inoculum potential as determined by bioassay, are not always consistent with each other.  相似文献   
107.
To evaluate the effect of lipid-lowering agents upon egg quality, reproductive performance, plasma lipids, and egg yolk cholesterol levels, 30-week-old Shaver laying hens were fed a basal diet (commercial ration) supplemented with 0.1% probucol (PROB), 0.025% gemfibrozil (GEMF), or lovastatin at 0.0005% (LOV1), 0.001% (LOV2), or 0.0015% (LOV3) for a 12-week experimental period. It was observed that the supplementation of the drugs did not impair albumen and shell quality. Hen performance was not adversely affected. The depression in triglyceride concentrations approached statistical significance only in LOV2 (38.5%), and total cholesterol was significantly depressed in LOV2 (36.0%), LOV3 (36.8%), PROB (29.6%), and GEMF (30.4%) treatments. Egg cholesterol content, expressed per gram of yolk, was significant lowered in LOV1 (7.5%) and LOV3 (12. 7%).  相似文献   
108.
The molecular structure and some physicochemical properties of starches from two high‐amylose cultivars of barley, high‐amylose Glacier A (HAG‐A) and N (HAG‐N), were examined and compared with those of a normal cultivar, Normal Glacier (NG). The true amylose contents of HAG‐A, HAG‐N, and NG were 41.0, 33.4, and 23.0%, respectively. Iodine affinities before and after defatting of starch, and thermograms of differential scanning calorimetry, indicated that HAG‐A and HAG‐N starches had a higher proportion of amylose‐lipid complex than did NG starch. The amylopectins from HAG‐A and HAG‐N were similar to NG amylopectin in average chain length (18–19), β‐amylolysis limit (β‐AL 56–57%), number‐average degrees of polymerization (DPn 6,000–7,500) and chain length distribution. Very long chains (1–2%) were found in amylopectins from all cultivars. HAG‐A amylopectin had a larger amount of phosphorus (214 ppm) than the others. The amyloses from HAG‐A and HAG‐N resembled NG amylose in DPn (950–1,080) and β‐AL (70–74%). However, HAG‐A and HAG‐N had a larger number of chains per molecule (NC 2.4–2.7) than NG amylose (1.8) and contained the branched amylose with a higher NC (9.5–10.6) than that of NG amylose (5.8), although molar fractions of the branched amylose (15–20%) were similar.  相似文献   
109.
An aquabirnavirus (ABV) and a formalin-inactivated betanodavirus [redspotted grouper nervous necrosis virus (RGNNV)] were investigated for their potential to prevent RGNNV-induced viral nervous necrosis (VNN) in the sevenband grouper, Epinephelus septemfasciatus (Thunberg). Three groups of fish were injected intramuscularly with ABV, intraperitoneally with inactivated RGNNV (iRGNNV) or with both ABV and iRGNNV. At 3, 7, 14, 21 and 28 days post-injection (p.i.), fish were challenged by intramuscular injection of RGNNV. Control fish, which received neither ABV nor iRGNNV, showed high mortalities in all RGNNV challenges. Fish that received only ABV exhibited relative percent survival (RPS) of >60 against RGNNV challenges at 3, 7, 14 and 21 days p.i., but not at 28 days p.i., while fish that received only iRGNNV showed significantly higher protection against RGNNV challenges only at 21 and 28 days p.i. In contrast, fish that received both ABV and iRGNNV showed 60 or higher RPS against all RGNNV challenges. Fish inoculated with iRGNNV with or without ABV exhibited similar high titres of neutralizing antibodies to RGNNV at 14, 21 and 28 days p.i. These results indicate that combined inoculation with iRGNNV and ABV conferred both rapid non-specific and delayed specific protection against VNN.  相似文献   
110.
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