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61.
1. CVI-ChNL 74·3, a dendritic cell-specific monoclonal antibody (mAb) also identifies chicken lung granular pneumocytes (type II pneumocytes), which produce surfactant.

2. The 74·3 mAb does not cross-react with any other avian or mammalian granular pneumocyte, and provides a convenient tool for monitoring the status of type II pneumocytes in the chicken lung.  相似文献   

62.
RFamide‐related peptide‐3 (RFRP‐3), the mammalian ortholog of gonadotropin‐inhibiting hormone, has been implicated as a mediator between reproduction and energy balance. This study aimed to investigate the physiological effects of RFRP‐3 on the process of ovarian development in food‐restricted pre‐pubertal ewes. The results showed that food restriction significantly inhibited the ovarian development and follicular growth. The data of qPCR in the hypothalamic–pituitary–ovarian (HPO) axis showed that food restriction not only upregulated RFRP‐3 mRNA expression but also downregulated the mRNA expression of gonadotropin‐releasing‐hormone receptor, follicle‐stimulating hormone receptor and luteinizing hormone receptor (LHR). Immunohistochemistry of RFRP‐3 in the ovaries suggested that RFRP‐3 may regulate the follicular development. These results suggested that the changes of RFRP‐3 in response to food restriction might influence the HPO axis and inhibit ovarian development.  相似文献   
63.
The investigation involved 4 mastitis-free cows, exposed to 168 h of suspended milking to induce prolonged milk stasis and premature mammary regression during mid-lactation. After 48 h the milk stasis elicited mastitis-like changes in the clinical, somatic cell count (SCC), bovine serum albumin (BSA) and beta-N-acetyl-D-glucosaminidase (NAG) characteristics of the udder secretions. Such changes in secretions from non-mastitic regressive mammary glands raise doubts about the present knowledge, definition, and diagnosis of so-called non-specific or aseptic mastitis. Determinations of fluctuating lacteal concentrations of lactose, galactose, mannose and glucose suggest that the secretory epithelium altered its metabolism and integrity in response to the intramammary perturbation by following a certain pattern of regressive adjustments which: (i) were apparently triggered during the initial 24 h of perturbation by disturbed Na-K-ATPase activities, followed by a cascade of changes in ion regulation, carbohydrate metabolism and increased formation of lactic acid as a metabolic end-product; (ii) advanced in a stepwise fashion during 0-24, 24-72 and 72-168 h of perturbation from recognition response to alarm reactions and manifestation of regression respectively; (iii) showed that markedly decreased carbohydrate levels preceded major increases of the SCC, BSA and NAG values; (iv) indicated that after 72 h of milk stasis leucocytic infiltrations sharply increased the SCC to more than 500,000 per ml and accelerated the manifestation of regression. The results of this study imply that extensive premature regression of healthy, and especially, pre-irritated udders could have significant implications for the development of different types of bovine mastitis during lactation and should be further investigated.  相似文献   
64.
Two groups of cows infected with the bovine leukosis virus (BLV) were kept on two different diets and the fat content of their milk was assayed. The results were compared with those obtained from two comparable groups of BLV-free cows. The cows in each group were of similar ages, those in the groups on the poorer diet being 1–4 months post partum, while those on the richer diet were 5–7 months post partum. The mean percentage of fat in the milk from uninfected cows on the poorer diet was 2.94 while that from the similar infected cattle was 3.06. Uninfected cows on the richer diet produced milk containing 3.39% fat, while those that were infected produced milk containing 3.30% fat. No statistical differences in milk fat production were observed between the BLV seropositive and seronegative cows.  相似文献   
65.
BACKGROUND: Fine needle aspiration (FNA) offers a rapid and minimally invasive means to distinguish malignant from benign neoplasms. However, few studies have been published regarding the cytopathology of mammary tumors in rats despite widespread use of the rat model for breast cancer formation and inhibition. OBJECTIVE: The purpose of this study was to determine the diagnostic accuracy of FNA cytology and to develop distinguishing cytologic criteria for the diagnosis of radiation-induced benign and malignant mammary tumors in rats. METHODS: In a study of radiation-induced mammary carcinogenesis, 100 Sprague-Dawley rats with cutaneous masses were randomly chosen for FNA. The aspirates were smeared, fixed, and stained with a modified Papanicolaou procedure for diagnostic evaluation. Cytologic and histologic diagnoses (benign vs malignant) were compared, and diagnostic accuracy was calculated using the histologic diagnosis as the criterion standard. FNA smears were scored semiquantitatively on a scale of 1-4 for cellularity, atypia, nuclear size, chromatin pattern, nuclear membrane thickness, nucleoli, and mitoses. The background was evaluated for necrosis, hemorrhage, inflammation, and mucosecretory material. Cytomorphologic features were compared statistically between benign and malignant tumors, based on the histologic diagnosis. RESULTS: The sensitivity of FNA was 92.3% and specificity was 89.4% for the detection of malignancy. However, 14% of specimens, all fibroadenomas by histology, had insufficient cells for cytologic evaluation, for an overall accuracy rate of 78.0%. Malignant tumors had significantly higher scores for all cytomorphologic features, and were significantly more likely to contain cell clusters and necrotic debris. CONCLUSIONS: FNA is an accurate method for differentiating benign and malignant rat mammary tumors.  相似文献   
66.
The splenic lobe (Lobus splenicus) of the pancreas of young meat-type quails (Coturnix c. japonica) was examined by immunohistochemical and light microscopic methods. The endocrine cells are mainly grouped as alpha, beta and mixed islets. A large region consisting of alpha cells is located in the central region of the splenic lobe whereas numerous beta islets are detected in the periphery of the splenic lobe. Alpha islets are in the majority composed of toluidine blue positive A cells and a few toluidine blue negative D and / or avian pancreatic polypeptide (APP) endocrine cells. Beta islets contain only a few toluidine blue negative B and a few D cells. Immunohistochemical staining of the splenic lobe reveal in the centre of beta islets numerous insulin immunoreactive cells and scarcely in alpha islets, exocrine tissue and / or among acinar cells. Somatostatin immune-reactive cells form a circular layer in the periphery of beta islets whereas these cells are uniformly distributed throughout the alpha islet parenchyma and exocrine tissue. In conclusion, the morphology but also the endo- and exocrine functions of the splenic lobe of quails are similar to observations in other avian species such as chicken, duck, goose and pigeon.  相似文献   
67.
Thoracoscopic biopsies were taken from four dogs with lung tumours using a Roeder's loop. A Roeder's loop is used to collect pulmonary tissue samples for histopathological analyses. In all the animals tissue biopsy using a Roeder's loop enabled to collect a relatively large specimen of the lung tumor tissue.  相似文献   
68.
A study on bioavailability and pharmacokinetics of cefquinome in piglets was conducted after intravenous (i.v.) and intramuscular (i.m.) administrations of 2.0 mg/kg of body weight, respectively. Plasma concentrations were measured by high‐performance liquid chromatography assay with UV detector at 268‐nm wavelength. Plasma concentration–time data after i.v. administration were best fit by a two‐compartment model. The pharmacokinetic values were distribution half‐life 0.27 ± 0.21 h, elimination half‐life 1.85 ± 1.11 h, total body clearance 0.26 ± 0.08 L/kg·h, area under curve 8.07 ± 1.91 μg·h/mL and volume of distribution at steady state 0.46 ± 0.10 L/kg. Plasma concentration–time data after i.m. administration were also best fit by a two‐compartment model. The pharmacokinetic parameters were distribution half‐life 0.88 ± 0.42 h, elimination half‐life 4.36 ± 2.35 h, peak concentration 4.01 ± 0.57 μg/mL and bioavailability 95.13 ± 9.93%.  相似文献   
69.
In this study we have compared protein secretion in the wild type of S. Typhimurium and the rfaC mutant. We found out that the rfaC mutant was defective in protein secretion. In addition, the rfaC mutant was defective in its invasion into an IPEC-J2 porcine epithelial cell line and also in motility in semisolid agar. Consistent with this, reduced flagella numbers were observed in the rfaC mutant. In the rfaC mutant, there were no defects in flagellin expression as detected by western blot and immune electron microscopy which demonstrated equal amounts of flagellin in the cytoplasm of both the rfaC mutant and the wild-type S. Typhimurium. However, in the wild-type strain only, the flagellin was assembled to spatially restricted areas on the inner side of cytoplasmic membrane. The oligosaccharide core of LPS is therefore required for the assembly of flagella and T3SS secretion machinery followed by protein secretion.  相似文献   
70.
通过2个试验研究接种nocardia corynebacte-roides(NC)细菌对黄曲霉毒素污染肉鸡饲料的生物脱毒作用。第1个试验研究了NC细菌的致病性(安全性);第2个试验对脱毒饲料的营养价值进行了评估。将玉米分为2份,其中1份污染黄曲霉毒素,再将这2份玉米分别分为2小份,其中1小份接种NC细菌,然后使用这4个玉米样品配制4种玉米-豆粕日粮,形成完全随机的2×2析因分析设计,包括污染或不污染AF、接种或不接种NC细菌。试验选用100只1日龄Ross 308公雏,分为4个处理组,每个处理组5个重复,每个重复5只鸡。每周记录体重和耗料量,并从每个重复组中选择一只鸡屠宰,对肝脏、肾脏、法氏囊、胰脏以及小肠(包括十二指肠、盲肠、结肠)进行组织病理学分析,同时对小肠的3个部分进行电子显微镜分析,在21日龄试验结束时,每个重复组再屠宰1只鸡,测定肝脏中水分和脂肪含量以及AF残留量。3周的试验结果表明,处理组之间各项病理指标无显著差异(P>0.05)。第2个试验增大了AF的污染量(800和1200μg/kg饲料),其他与试验1相同。结果表明,处理组之间在体重、肝脏脂肪含量和AF残留量上存在显著差异(P<0.05);肝脏、十二指肠以及肾脏的损伤严重程度也存在显著差异;电子显微镜扫描结果表明,AF严重损伤肠黏膜紧密连接处。综上所述,NC细菌对鸡是安全的,可用于AF污染肉鸡饲料的生物脱毒。  相似文献   
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