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81.
Petterino C Martini M Castagnaro M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(5):569-572
The aim of this study was to detect immunohistochemically means growth hormone (GH) in 24 hepatoid gland adenomas and 5 hepatoid gland carcinomas and to compare the difference of immunoreactivity between types of tumors. The tumors were classified according to the WHO standards. Tissue sections which were prepared from formalin-fixed, paraffin wax-embedded tissues from 25 male and 4 female dogs were carried out immunostaining using polyclonal primary anti-hGH and EnVision method. Of 24 hepatoid gland adenomas (perianal gland adenomas) 23 (95.8%) were positive. All 5 hepatoid gland carcinomas (perianal gland carcinomas) were positive. No statistically significant differences in percentage of labelled cells between malignant and benign tumors were seen. The present demonstration of GH in hepatoid gland tumors adds new data on GH in extra-pituitary tissues and hormon-dependent tumors. 相似文献
82.
Montagna P McCulloch M Taviani M Mazzoli C Vendrell B 《Science (New York, N.Y.)》2006,312(5781):1788-1791
Phosphorus is a key macronutrient being strongly enriched in the deep ocean as a result of continuous export and remineralization of biomass from primary production. We show that phosphorus incorporated within the skeletons of the cosmopolitan cold-water coral Desmophyllum dianthus is directly proportional to the ambient seawater phosphorus concentration and thus may serve as a paleo-oceanographic proxy for variations in ocean productivity as well as changes in the residence times and sources of deep-water masses. The application of this tool to fossil specimens from the Mediterranean reveals phosphorus-enriched bottom waters at the end of the Younger Dryas period. 相似文献
83.
Klöhn PC Farmer M Linehan JM O'Malley C Fernandez de Marco M Taylor W Farrow M Khalili-Shirazi A Brandner S Collinge J 《Science (New York, N.Y.)》2012,335(6064):52
Intraperitoneal administration of ICSM18 and 35, monoclonal antibodies against prion protein (PrP), has been shown to significantly delay the onset of prion disease in mice, and humanized versions are candidate therapeutics for prion and Alzheimer's diseases. However, a previous report of severe and widespread apoptosis after intracerebral injection of anti-PrP monoclonal antibodies raised concerns about such therapy and led to an influential model of prion neurotoxicity via cross-linking of cell surface PrP by disease-related PrP aggregates. In extensive studies including ICSM18 and 35, fully humanized ICSM18, and the previously reported proapoptotic antibodies, we found no evidence of apoptosis, thereby questioning this model of prion neurotoxicity. 相似文献
84.
Faini M Prinz S Beck R Schorb M Riches JD Bacia K Brügger B Wieland FT Briggs JA 《Science (New York, N.Y.)》2012,336(6087):1451-1454
Transport between compartments of eukaryotic cells is mediated by coated vesicles. The archetypal protein coats COPI, COPII, and clathrin are conserved from yeast to human. Structural studies of COPII and clathrin coats assembled in vitro without membranes suggest that coat components assemble regular cages with the same set of interactions between components. Detailed three-dimensional structures of coated membrane vesicles have not been obtained. Here, we solved the structures of individual COPI-coated membrane vesicles by cryoelectron tomography and subtomogram averaging of in vitro reconstituted budding reactions. The coat protein complex, coatomer, was observed to adopt alternative conformations to change the number of other coatomers with which it interacts and to form vesicles with variable sizes and shapes. This represents a fundamentally different basis for vesicle coat assembly. 相似文献
85.
86.
Darwich L Cabezón O Echeverria I Pabón M Marco I Molina-López R Alarcia-Alejos O López-Gatius F Lavín S Almería S 《Veterinary parasitology》2012,183(3-4):377-381
Toxoplasma gondii infections are prevalent in many avian species and can cause mortality in some bird hosts. Although T. gondii has been isolated from various species of birds, the role of many different species of wild birds in the epidemiology of T. gondii remains unknown. Neospora caninum, a closely related parasite to T. gondii, has been recently confirmed to infect domestic chickens and wild birds such as house sparrows (Passer domesticus). The present study reports the presence of T. gondii and N. caninum DNA by PCR in brain tissues of 14 species of wild birds from Spain. From a total of 200 samples analyzed, 12 samples (6%) were positive for T. gondii [5 Eurasian jays (Garrulus glandarius), 5 magpies (Pica pica), 1 black kite (Milvus migrans) and 1 Griffon vulture (Gyps fulvus)], while 3 samples (1.5%) were positive for N. caninum [2 magpies and 1 common buzzard (Buteo buteo)]. This is the first report of detection of T. gondii in magpies, griffon vulture and black kite and of N. caninum in common buzzard and magpies, extending the list of natural intermediate hosts for T. gondii and N. caninum infections to these species. 相似文献
87.
Roberto A. Santilli Alessia Diana Marco Baron Toaldo 《Journal of Veterinary Cardiology》2012,14(2):363-370
Electrocardiographic tracings of an English Bulldog referred for cardiogenic shock due to an orthodromic atrioventricular reciprocating tachycardia conducted with intraventricular conduction disturbance and mimicking ventricular tachycardia (VT) are presented. At admission the surface ECG showed a wide QRS complex tachycardia (WCT) that was converted to sinus rhythm using manual cardioversion (chest thump). This change revealed pre-existing right bundle branch block, and a final diagnosis of supraventricular tachycardia (SVT) with intraventricular conduction disturbance was made. Electrophysiologic study defined the SVT mechanism as an atrioventricular macroreentrant tachycardia mediated by a single mid-septal accessory pathway. The differentiation between various types of WCT is essential when antiarrhythmic therapy is considered. The surface ECG should be systematically evaluated in order to recognize the characteristic features of SVT and VT. Moreover chest thump procedure can be very helpful in the attempt to convert the rhythm to sinus rhythm and to correctly recognize the underlying arrhythmia. 相似文献
88.
89.
Wibke Himmelsbach Eduardo J. Treviño-Garza Humberto González-Rodríguez Marco A. González-Tagle Marco V. Gómez Meza Oscar A. Aguirre Calderón A. Eduardo Estrada Castillón Ralph Mitlöhner 《European Journal of Forest Research》2012,131(2):355-367
Water availability and salt excess are limiting factors in Mexican mixed pine-oak forest. In order to characterise the acclimatation
of native species to these stresses, leaf water (Ψw) and osmotic potentials (Ψs) of Juniperus flaccida, Pinus pseudostrobus and Quercus canbyi were measured under natural drought and non-drought conditions under two different aspects in the Sierra Madre Oriental.
Factorial ANOVA revealed significant differences in Ψw and Ψs between two aspects, species and sampling dates. In general, all species showed high predawn and low midday values that declined
progressively with increasing drought and soil–water loss. Seasonal and diurnal fluctuation of Ψw and Ψs were higher for J. flaccida and Q. canbyi than for P. pseudostrobus. Leaf Ψw and Ψs were mainly correlated with soil water content, while Ψs of P. pseudostrobus were hardly correlated with environmental variables. Thus, species have different strategies to withstand drought.
P. pseudostrobus was identified as a species with isohydric water status regulation, while J. flaccida and Q. canbyi presented water potential patterns typical for anisohydric species. The type of water status regulation may be a critical
factor for plant survival and mortality in the context of climate change. Nevertheless, for precise conclusions about the
advantages and disadvantages of each type, further long-term investigations are required. 相似文献
90.