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991.
A method for PEG treatment of bovine sera to be used for cell cultures is presented. The procedure consists in repeated freezing and thawing cycles of the sera, after PEG precipitation until a clear solution is obtained. The sera, so prepared, are homogeneous in composition and appropriate for cell growth in primary cell cultures and cell lines.  相似文献   
992.
蓖麻蚕蛹卵巢细胞的离体培养及其病毒感染试验   总被引:3,自引:0,他引:3  
浦秋文  胡敏 《蚕业科学》1989,15(1):56-57
本文采用不同的培养液在体外培养蓖麻蚕蛹卵巢细胞,比较观察细胞生长,发现这些细胞能连续传代。开始细胞生长相当慢,13代以后,生长加快,趋于稳定。并且发现这些细胞对蓖麻蚕核型多角体病毒十分敏感。  相似文献   
993.
Abstract— Epidermotropic cutaneous T-cell lymphoma was diagnosed in six Syrian hamsters (Mesocricetus auratus) with a generalised dermatosis characterised by pruritus, alopecia and exfoliative erythroderma. Plaques and nodules were evident in one animal. Clinical and histopathological findings were suggestive of mycosis fungoides and electron microscopical investigations in one case were supportive. Immuno-histochemical stains for CD3 antigen were strongly positive in all cases. Résumé— Un lyphome T cutané a été diagnostiqué chez six hamsters de Sibérie (Mesocricetus auratus) avec une dermatose généralisée, caractérisée par un prurit, une alopécle et une érythrodermie exfoliative. Des plaques et des nodules ont été observées sur un animal. Les données cliniques et histopathologiques étaient évocatrices d'un mycosis fungoïdes et les examens en microscopie électronique étaient compatibles dans un cas. Les marquages immuno-histochimiques de l'antigène CD3 étaient très positifs dans tous les cas. Zusammenfassung— Bei sechs Syrischen Goldhamstern (Mesocricetus auratus) wurde ein epidermotropes kutanes T-Zell-Lymphom mit einer generalisierten Dermatose diagnostiziert, die durch Pruritus, Alopezie und eine exfoliative Erythrodermie gekennzeichnet war. Bei einem Tier traten auch Plagues und Knoten auf. Die klinischen und histopathologischen Befunde deuteten auf Mycosis fungoides hin. Elektronenmikroskopische Untersuchungen unterstützten diesen Verdacht in einem Fall. Immunhistochemische Färbungen auf CD3-Antigen waren bei alien Fallen stark positiv. Resumen En un grupo de seis hamsters de siria, (Mesocricetus auratus), se diagnosticó limfoma epidermotrópico cutáneo de linfocitos T, presentando una dermatosis generalizada de tipo pruriginoso, acompañada de alopecia y eritroderma exfoliativo. Las placas y nódulos fueron evidentes en uno de los animales. Los estudios clinicos e histopatológicos indicaron una micosis fungoide, y las investigaciones de microscopía, en uno de los caseos, pareció indicar lo mismo. La tintura inmuno-histoquimica para el antígeno CD3 resultó claramente positiva en todod los casos.  相似文献   
994.
Genotyptc differences in wheat were observed in cell membrane with respect to injury caused by osmotic shock created with 40 per cent polyethylene glycol-6000. In general, genotypes with high cell membrane injury also registered much reduction in leaf water potential and osmotic potential. Cell membrane injury measured at 25 days after germination was found to be related with genotypic performance under drought conditions in field. Cell membrane stability measurements of normal plants, even at a very early stage of growth, is reported as criteria for selecting drought tolerant wheat genotypes.  相似文献   
995.
Abstract— Multiple squamous cell carcinomas in situ were diagnosed in five aged cats. Despite clinical courses ranging from 18 to 30 months, there was no clinical or histologic evidence of breachment of the basement membrane. The condition closely resembles Bowen's disease in humans.
Résumé— Des épithéliomas spinocellulaires multiples in situ ont été diagnostiqués chez 5 chats. Maigré une anclenneté clinique de 18 à 30 mois, il n'y avait pas de signes cliniques ou histologiques d'atteinte de la membrane basale. Cette affection resemble á la maladie de Bowen chez l'homme.
Zusammenfassung— Bei fünf alten Katzen wurden multiple plattenepithelkarzinome in situ diagnostiziert. Trotz der klinischen Krankheitverläufe von 18 bis 30 Monaten konnte weder klinisch noch histologisch ein Durchbrechen der Basalmembran nachgewiesen werden. Dieses Bild ähnelt sehr dem Bowens Krankheit des Menschen.
Resumen  En cinco gatos se diagnosticaron carcinomas multiples de células escamosas in situ. A pesar del curso clínico de 18–30 meses no se observó evidencia clinica, o histológica de infiltración a traves de la membrana basal. La condición es muy semejante a la enfermedad de Bowen en medicina humana.  相似文献   
996.
The effect of a water-soluble fraction (WSF) of a non-pathogenic strain of Mycobacterium phlei was studied in bovine subclinical mastitis (SCM) by measuring the myeloperoxidase and acid phosphatase enzyme levels in the milk leukocytes. Forty-five cows were divided into three equal groups. Group I, consisting of 15 healthy cows, served as the control, whereas groups II and III each contained 15 cows with subclinical mastitis on the basis of a positive reaction in the California mastitis test (CMT). The cows in group II received 100 microg of WSF in 5 ml sterile phosphate-buffered saline, pH 7.4 (PBS) once only, while those in group III received 5 ml sterile PBS daily for 7 days, both treatments being given by the intramammary route. Observations were made up to 30 days after treatment (AT). The CMT of the healthy milk was negative (0), whereas it ranged between 1 and 2 points in SCM. The somatic cell count (SCC) increased significantly (p < 0.05) on day 3, then fell steeply from day 7 up to day 30 AT in the cows in group II. A steady decrease in the total bacterial count (TBC) was observed in the group treated with WSF but the bacterial counts remained high in the groups treated with PBS. The mean acid phosphatase level was enhanced by 119% on day 3 AT in group II but only by 18.7% in the cows in group III. The mean myeloperoxidase level was enhanced by 100% in the cows in group II but only by 18% in those in group III on day 3 AT. This significant reduction in the bacterial load in infected cows caused by intramammary infusion of WSF may be due to activation of the microbicidal activity of the neutrophils, but this requires confirmation.  相似文献   
997.
Two 12-week-old Tippler pigeons were evaluated for ocular abnormalities associated with congenital blindness. The pigeons were emaciated and blind. Biomicroscopy and direct and indirect ophthalmoscopy findings of the Tippler pigeons were normal with the exception of partially dilated pupils at rest. Scotopic (blue stimuli) and photopic monocular electroretinograms were extinguished in the blind Tippler pigeons. Histological and electron microscopy studies revealed reduced numbers of rods and cones, and an absence of the double cone complex. The photoreceptor cells' outer segments were absent, and the inner segments were short and broad. The number of cell nuclei in the outer and inner nuclear layers was decreased, and the internal and external plexiform layers were reduced in width. Photoreceptor cell endfeet with developing synaptic ribbons were present in the external plexiform layer. Inflammatory cell and subretinal debris was not seen. The electroretinographic, histopathological, and ultrastructural findings of the blind Tippler pigeons support the diagnosis of a photoreceptor cell dysplasia.  相似文献   
998.
This study compared concentrations of amyloid A in bovine milk with the cell-based indicators of intramammary inflammation, somatic cell count and California Mastitis Test. Mammary quarter data pertaining to 180 cows were categorised according to concentrations of serum amyloid A in the cow of origin. Ranked correlation, ranked regression and receiver operator characteristics all demonstrated acceptable agreement between milk amyloid A concentrations and cell-based indices. There were some indications of reduction in this agreement, in cows with raised concentrations of serum amyloid A. However, there were also indications that serum amyloid A did not significantly influence milk amyloid A. The results of the current study indicate that milk amyloid A exhibits good correlation with established cell-based indicators of intramammary inflammation.  相似文献   
999.
Haemophilus somnus lipooligosaccharide (LOS)-induced apoptosis of bovine pulmonary artery endothelial cells has been shown previously to be dependent on capsase-8 activation. Activation of caspase-8 can occur via a death receptor-dependent mechanism (e.g., TNF- binding to TNF- receptor 1 (TNF-R1)). In this study, we tested the hypothesis that TNF- can enhance LOS-induced apoptosis of bovine endothelial cells. Addition of exogenous recombinant human TNF- alone failed to cause apoptosis, or enhance LOS-induced apoptosis, of bovine endothelial cells. However, blocking de novo protein synthesis by addition of cycloheximide significantly enhanced apoptosis of bovine endothelial cells by TNF-, LOS or TNF- and LOS in combination. Conversely, addition of soluble recombinant human (sTNF-R1) diminished LOS-induced apoptosis. Overall, these data suggest that LOS-mediated apoptosis may be due, in part, to activation of a TNR-R1-dependent death pathway.  相似文献   
1000.
 本文利用BOI(Botrytis Susceptible 1 Interactor)基因敲减(knock-down) 株系、过量表达株系以及烟草瞬时表达系统,研究了BOI 基因在细胞程序化死亡(PCD)中的作用以及BOI 蛋白中RING 和WRD 结构域的功能。结果表明,BOI 基因的表达下调导致抗氧化胁迫能力下降,弱化了对活性氧介导的PCD 抑制作用;BOI 过量表达或瞬间表达可以增强对活性氧介导和α-吡啶甲酸诱导的PCD 的抑制作用。进一步研究发现,BOI 蛋白中的RING 结构域是BOI 抑制PCD 所必需的,WRD 结构域与BOI 对PCD 的抑制作用关系不大。  相似文献   
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