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51.
This case report describes the clinical, radiographic, ultrasonographic and histopathological findings of a six-month-old heifer, suffering from bilateral fracture of the calcaneal tuber caused by osteochondrosis. The young cattle was admitted to the clinic for the evaluation of a left hindlimb lameness, having persisted for several weeks. Orthopaedic examination revealed a highly stilted gait with a lameness of the left hind limb, so severe that the heifer was only able to put some weight on the tip of the toe. The calcaneal region on both hindlimbs showed a diffuse swelling, palpation being very painful. The radiological examination revealed a fracture of the calcaneal tuber (apophyseolysis) of both hindlimbs.  相似文献   
52.
Für die Tiefgefrierkonservierung von Mäuse- und Rinderembryonen wird eine einfache Gefrier- und Auftauapparatur beschrieben. Die Tiefgefrierung des Gefriergutes erfolgt in der Dampfphase eines offenen Stickstoffbehälters in einem variablen Abstand rum Flüssigkeitsspiegel. Das Gefriergut ist lotrecht über dem Behälter in einem fixen Drahtkörbchen deponiert. Eine vertikal bewegliche Hubvorrichtung hebt den Behälter, eine Styroporbox, an, wobei das Gefriergut in den Stickstoffdampf ver-senkt wird. Der Antrieb erfolgt iiber einen Elektromotor rnit Untersetzungsgetriebe und manueller Aussteuerung, womit Hub- und Gefriergeschwindigkeit reguliert werden. Aus den mit dieser Apparatur tieiqefrorenen Mäuse- und Rinderembryonen sind lebende Junge hervorgegangen .  相似文献   
53.
Hematopoietic malignancies are the most commonly reported neoplasms in lizards, occurring sporadically as in other reptiles. An unusually high incidence of lymphoid neoplasia occurred in a collection of Egyptian spiny-tailed lizards (Uromastyx aegyptius) from 1993-2001. Eight of 15 lizards necropsied at the Louisville Zoological Garden (53%) had multicentric lymphoma. Immunohistochemistry was not useful in characterizing the lineage of normal or neoplastic lymphocytes. By light and electron microscopy (EM), the neoplasms had plasmacytoid morphologic features suggesting B-cell origin, although some tumors also had a primitive lymphoblast component. A concurrent leukemic blood profile was identified in seven of the cases (88%). All were adult animals and no sex predilection was observed. No exposure to exogenous carcinogens was observed. Some of the lizards were unrelated, so hereditary factors were unlikely. Although examination by EM and viral isolation performed on archived tissues and plasma failed to detect viruses, an infectious etiology still warrants consideration.  相似文献   
54.
Since the early 1980s, investigations by health departments of eight counties in southern New Jersey, by the NJ Department of Environmental Protection (NJDEP), and subsequently by the US Geological Survey (USGS), have shown that Hg concentrations in water tapped by about 600 domestic wells exceed the maximum contaminant level (MCL) of 2 μg/L. The wells are finished in the areally extensive unconfined Kirkwood-Cohansey aquifer system of New Jersey's Coastal Plain; background concentrations of Hg in water from this system are < 0.01 μg/L. Evidence of contributions from point sources of Hg, such as landfills or commercial and industrial hazardous-waste sites, is lacking. During 1996–2003, the USGS collected water samples from 203 domestic, irrigation, observation, and production wells using ultraclean techniques; septage, leach-field effluent, soils, and aquifer sediments also were sampled. Elevated concentrations of NH4, B, Cl, NO3, and Na and presence of surfactants in domestic-well water indicate that septic-system effluent can affect water quality in unsewered residential areas, but neither septage nor effluent appears to be a major Hg source. Detections of hydrogen sulfide in ground water at a residential area indicate localized reducing conditions; undetectable SO4 concentrations in water from other residential areas indicate that reducing conditions, which could be conducive to Hg methylation, may be common locally. Volatile organic compounds (VOCs), mostly chlorinated solvents, also are found in ground water at the affected areas, but statistically significant associations between presence of Hg and VOCs were absent for most areas evaluated. Hg concentrations are lower in some filtered water samples than in paired unfiltered samples, likely indicating that some Hg is associated with particles or colloids. The source of colloids may be soils, which, when undisturbed, contain higher concentrations of Hg than do disturbed soils and aquifer sediments. Soil disturbance during residential development and inputs from septic systems are hypothesized to mobilize Hg from soils to ground water.  相似文献   
55.
Ten different barley varieties grown in one location were studied for their content of tocols, folate, plant sterols, alkylresorcinols, and phenolic acids, as well as dietary fiber components (arabinoxylan and beta-glucan). The samples included hulled and hull-less barley types and types with normal, high-amylose, and waxy starch. The aim was to study the composition of raw materials, and therefore the hulls were not removed from the hulled barleys. A large variation was observed in the contents of all phytochemicals and dietary fibers. Two varieties from the INRA Clermont Ferrand barley program in France (CFL93-149 and CFL98-398) had high content of tocopherols and alkylresorcinols, whereas the variety Dicktoo was highest in dietary fiber content and phenolics. Positive correlations were found between 1000 kernel weight, alkylresorcinols, and tocols, as well as between dietary fiber content and phenolic compounds. The results demonstrate that the levels of phytochemicals in barley can likely be affected by breeding and that the contents of single phytochemicals may easily be adjusted by a right selection of a genotype.  相似文献   
56.
Detection Technologies. Ambient mass spectrometry   总被引:1,自引:0,他引:1  
A recent innovation in mass spectrometry is the ability to record mass spectra on ordinary samples, in their native environment, without sample preparation or preseparation by creating ions outside the instrument. In desorption electrospray ionization (DESI), the principal method described here, electrically charged droplets are directed at the ambient object of interest; they release ions from the surface, which are then vacuumed through the air into a conventional mass spectrometer. Extremely rapid analysis is coupled with high sensitivity and high chemical specificity. These characteristics are advantageously applied to high-throughput metabolomics, explosives detection, natural products discovery, and biological tissue imaging, among other applications. Future possible uses of DESI for in vivo clinical analysis and its adaptation to portable mass spectrometers are described.  相似文献   
57.
Clinical, ultrasonographic, radiographic and pathological findings of a chondrosarcoma diagnosed in an 8-year-old Simmental cow are reported. The primary site was located in the cartilage of the right scapula at the angulus cranialis. The tumour had already spread to the lungs at the time of diagnosis. This is the first report of a bovine scapula chondrosarcoma.  相似文献   
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