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41.
A deformed liver characterized by remarkable ductular proliferation was encountered in a 6-month-old pig and examined histopathologically. The most conspicuous histopathologic change was a mild to severe ductular proliferation in the interlobular areas without any degenerative changes of cholangiolar epithelial cells or hepatocytes. Fibrotic changes and reconstruction of the lobule were not found. Morphological evidence of intrahepatic and extrahepatic cholestasis was lacking. Other characteristics were deformity with displacement of the gall bladder, irregular shape and size of lobules, and structural abnormality of large-sized vessels. The severe ductular proliferation was considered to be due to structural malformations of the excretion channel of bile.  相似文献   
42.
The use of analgesics in post‐operative adhesion (POA) research is problematic due to POA‐inhibiting effects of anti‐inflammatory agents and bowel motility‐inhibiting effects of opioids, which may increase adhesion formation. This study was conducted to assess a buprenorphine (BUP) protocol for analgesic efficacy and its effects on POA formation in a rat cecal abrasion model. The protocol was approved by the University of Florida's Institutional Animal Care and Use Committee (IACUC). Forty‐one female Sprague‐Dawley rats were randomized into two groups (n = 20 or 21 group). Body weight, food and water intake were recorded daily from 2 days before until 7 days after surgery. Treatment rats received 0.05 mg kg–1 BUP SQ at anesthesia induction and 0.3 mg kg–1 BUP orally in flavored gelatin 6 hours after surgery. Control rats received saline placebo injection and plain gelatin. All rats underwent laparotomy and controlled cecal abrasion. At 3, 6 and 24 hours post‐operatively rats were individually observed in 10‐minutes periods for pain related behavior incidence: ‘twitch’ (contraction of muscles along dorsum and/or head), ‘back arch’ (cat‐like position with front legs extended and pushing backward), ‘writhe’ (flank contraction), and ‘stagger/fall’ (momentary loss of balance while grooming or ambulating), using the method of Roughan and Flecknell (Pain 2001,90, 65–74). On post‐op day seven rats were euthanized by CO2 inhalation and POA evaluated (0 to 4 scale; ³Grade 2 = clinically significant.) BUP treated rats had lower mean pain scores than control rats at 3 hours (1.6 ± 1.7 versus 20.3 ± 13.5 (mean ± SD); p < 0.001) and 6 hours (2.1 ± 2.7 versus 23.7 ± 12.9; p < 0.001) but not 24 hours (1.5 ± 1.3 versus 4.9 ± 6.6; p = 0.35) post‐operatively. Predominant pain behavior was ‘writhe’ (flank contraction) in contrast to ‘twitch,’‘back arch,’ and ‘stagger/fall’ reported as most common pain indicators in other rat strains. BUP rats had greater mean adhesion incidence (2.4 ± 1.7 versus 1.4 ± 1.8; p < 0.03) and severity (90%³Gr.2 versus 65% of controls; p < 0.05). The BUP protocol appeared to provide effective analgesia for at least 24 hours post‐operatively. Strain of rat may affect pain related behavior. BUP should be used with caution after abdominal surgical procedures having high risk of POA formation.  相似文献   
43.
Mast cell tumors (MCTs) of gastrointestinal origin that had been surgically removed from 39 dogs were examined to evaluate their pathologic features. Miniature breeds, especially Maltese, were most frequently affected. The average age of affected dogs was 9.7 +/- 2.6 years. No sex difference was apparent. The most frequently affected sites were in the upper digestive tract, and the prognosis was very poor. Grossly, the gastrointestinal wall was prominently thickened, and the lumen of the affected gut was usually narrowed. Microscopically, there was diffuse transmural invasion of round to pleomorphic tumor cells. Tumor cells had moderate to abundant cytoplasm, round to ovoid nuclei with scattered chromatin, and mitotic figures. Fibrous stroma was observed in about half of the tumors. There was variable infiltration of eosinophils. In all tumors, cytoplasmic granules showed weak metachromasia, but the number of granules was very small. Immunohistochemical staining for c-kit and mast cell tryptase was positive in 77% and 62% of tumors, respectively. All tumors were positive for at least two of these markers. Immunohistochemical staining for p53 was positive in 13% of the tumors. Reactivity for staining markers and p53 was unrelated to cell pleomorphism, vessel invasion, or survival time. Gastrointestinal MCTs have histologic and immunohistochemical features completely different from those of other primary or metastatic gastrointestinal tumors. The combination of immunostaining for mast cell tryptase and c-kit and histochemical staining for metachromasia appears to be a powerful tool for the diagnosis of gastrointestinal MCTs.  相似文献   
44.
Tumors of the nasal cavity or paranasal sinuses of 18 dogs were examined histopathologically, immunohistochemically, and histochemically. The tumors were classified histologically as 13 adenocarcinomas, 3 transitional carcinomas, 1 squamous cell carcinoma, and 1 adenosquamous carcinoma. Tumor cells were strongly immunoreactive for broad-spectrum cytokeratins in all cases, for cytokeratin 8/18 in 16 cases, and for cytokeratin 19 in 17 cases. None of the 18 carcinomas had cytologic or histologic features indicative of neuroendocrine differentiation, yet tumor cells in 5 of the 13 adenocarcinomas were argyrophilic and immunohistochemically positive for synaptophysin and chromogranin A. Results of this study indicate that neuroendocrine markers may be detected immunohistochemically and histochemically in canine nasal or paranasal adenocarcinomas despite the lack of typical histologic features of neuroendocrine differentiation.  相似文献   
45.
46.
The thermal treatment of chicken meats was investigated by generalized 2D visible/NIR correlation spectroscopy. Synchronous 2D visible correlation analysis revealed that there are at least two bands around 445 and 560 nm, decreasing in intensity with cooking time. The corresponding asynchronous spectrum indicated that the spectral intensity reduction of the two bands occurs before the intensity variation of the 475, 520, and 585 nm bands. It suggested that the 445 and 560 nm bands be assigned to deoxymyoglobin and oxymyoglobin, respectively, and at least one of the 475, 520, and 585 nm bands assigned to the denatured species (metmyoglobin) of myoglobin. Also, the asynchronous 2D NIR correlation spectrum indicated that C-H fractions are easily oxidized. In addition, strong correlation peaks correlating the bands in the visible, SW-NIR, and NIR spectral regions were observed and discussed.  相似文献   
47.
Shiotani H  Ozaki K  Tsuyumu S 《Phytopathology》2000,90(12):1383-1389
ABSTRACT The aggressiveness of strains of Xanthomonas axonopodis pv. citri on seven Citrus species, including Citrus sinensis (navel orange), C. paradisi (grapefruit), C. unshiu (Satsuma mandarin), C. junos (Yuzu), C. aurantifolia ('Mexican' lime), C. tachibana (Tachibana), and C. grandis (pummelo: 'Otachibana', 'Banpeiyu', and 'Anseikan'), were assessed by comparing lesion expansion and growth in planta, using a prick inoculation method. The existence of two groups distinct in aggressiveness was demonstrated on the pummelo cultivars, whereas the remaining species tested were uniformly susceptible. The two groups of strains were distinct in lesion expansion and growth in planta; however, both caused canker lesions on the 'Otachibana' pummelo. The sensitivity of the bacterial strains to phages Cp1 and Cp2 was associated with differences in aggressiveness. Namely, all the strains sensitive to Cp2 but resistant to Cp1 were aggressive to 'Otachibana', whereas all the strains sensitive to Cp1 but resistant to Cp2 were weakly aggressive. When a repetitive sequence-based polymerase chain reaction amplification was carried out by enterobacterial repetitive intergeneric consensus (ERIC) sequences (ERIC1R and ERIC2) as the primers, these two groups were also distinguishable by the presence or absence of a 1.8-kb DNA fragment among otherwise identical fragments. The 1.8-kb fragment was amplified only from the strains aggressive to C. grandis.  相似文献   
48.
49.
Interest in indicus–taurus cattle has been increasing, as these animals are likely to present the best characteristics of Zebu and European bovine breeds. The aim of this study was to compare the embryo production of indicus–taurus donors with high vs low antral follicle counts obtained by ovum pickup/in vitro production (OPU/IVP) and superovulation (SOV)/embryo collection. Braford females at weaning age (3/8 Nelore × 5/8 Hereford, n = 137, 9 ± 1 month old) were subjected to six serial ovarian ultrasonographs and were assigned to two groups according to the number of antral follicles ≥3 mm as follows: G‐High antral follicular count (AFC, n = 20, mean ≥40 follicles) and G‐Low AFC (n = 20, mean ≤10 follicles). When the females (n = 40) reached 24 months of age, they were subjected to both OPU/IVP and SOV/embryo collection. The average number of follicles remained highly stable throughout all of the ultrasound evaluations (range 0.90–0.92). The mean number of COCs recovered (36.90 ± 13.68 vs 5.80 ± 3.40) was higher (p < 0.05) for females with high AFC, resulting in higher (p < 0.05) numbers of total embryos among females with high vs low AFC (6.10 ± 4.51 vs 0.55 ± 0.83). The mean number of embryos per collection was also higher (p < 0.05) for G‐High vs G‐Low (6.95 ± 5.34 vs 1.9 ± 2.13). We conclude that a single ultrasound performed at pre‐pubertal ages to count antral follicles can be used as a predictor of embryo production following IVP and SOV/embryo collection in indicus–taurus females.  相似文献   
50.
Reconstitution of 30S ribosomal particles from 16S ribosomal RNA and total proteins, or from core proteins and split proteins obtained from the ribosomes of strains of Escherichia coli sensitive to and resistant to spectinomycin, shows that the split protein fraction determines the response of polypeptide synthesis in virto to spectinomycin. Reconstitution of active particles in the presence of isolated split proteins allowed the identification of the single split protein responsible for spectinomycin sensitivity.  相似文献   
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