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61.
OBJECTIVE: To determine the clinical usefulness of ultrasonography for diagnosis of meniscal pathology in dogs. STUDY DESIGN: Double-blind prospective study. ANIMALS: Dogs (n=10) with lameness localized to the stifle. MATERIALS AND METHODS: Sonographic examination of each affected stifle was performed by 1 ultrasonographer unaware of specific historical and clinical data for the dog. Sonographic findings were recorded, but not reviewed until study completion. Arthroscopic examination of the affected stifle was performed within 48 hours of ultrasonography by 1 surgeon unaware of ultrasonographic findings. Arthroscopic findings were recorded, but not reviewed until study completion. Two investigators compared the ultrasonographic and arthroscopic findings at study completion to determine the sensitivity, specificity, positive predictive value, and negative predictive value. RESULTS: Two of the 10 dogs had bilateral stifle evaluation. Twenty-four lateral and medial menisci, with normal and abnormal findings, were examined. The sensitivity and specificity for ultrasonographic diagnosis were 90.0% and 92.9%, respectively; positive and negative predictive values were 90.0% and 92.9%, respectively. CONCLUSIONS: Ultrasonography is highly specific and sensitive for diagnosing bucket handle tears of the medial meniscus in dogs. CLINICAL RELEVANCE: Ultrasonographic evaluation of menisci in dogs is a noninvasive method for accurately and efficiently diagnosing pathology, determining the need for surgical intervention, and providing comprehensive information to clients.  相似文献   
62.
The normal embryonic development of organs and other tissues in mice and all species is preprogrammed by genes. Inactivation of a gene involved in any stage of normal embryonic development can have severe consequences leading to embryonic or postnatal developmental defects and lethality. Pathology methods are reviewed for evaluating normal and abnormal placenta and embryo, especially after E12.5. These methods include pathology protocols for necropsy and histopathology in addition to references that will provide additional knowledge for embryo assessment including histology atlases and advanced embryo imaging techniques.  相似文献   
63.
A recombinant bovine herpesvirus 5 lacking thymidine kinase and glycoprotein E genes (BoHV-5gEΔTKΔ) was evaluated as a live experimental vaccine. In a first experiment, ten-months-old calves were vaccinated intramuscularly (n=9) or remained as controls (n=8) and 42 days later were challenged with BoHV-5 or BoHV-1 intranasally. The four control calves challenged with BoHV-5 developed severe depression and neurological signs and were euthanized in extremis at days 13 and 14 pos-infection (pi); the five vaccinated animals challenged with BoHV-5 remained healthy. The titers of virus shedding were reduced (p<0.01) from days 3 to 7 post-infection (pi) in vaccinated animals. Control and vaccinated calves challenged with BoHV-1 presented mild transient respiratory signs; yet the magnitude of virus shedding was reduced (p<0.05) in vaccinated animals (days 5, 9 and 11pi). In a second experiment, young calves (100-120 days-old) were vaccinated (n=15) or kept as controls (n=5) and subsequently challenged with a BoHV-1 isolate. Control calves developed moderate to severe rhinitis and respiratory distress; two were euthanized in extremis at days 5 and 9 pi, respectively. In contrast, vaccinated animals were protected from challenge and only a few developed mild and transient nasal signs. The duration and titers of virus shedding after challenge were reduced (p<0.05) in vaccinated animals comparing to controls. In both experiments, vaccinated animals developed antibodies to gE only after challenge. These results demonstrate homologous and heterologous protection and are promising towards the use of the recombinant BoHV-5gEΔTKΔ in vaccine formulations to control BoHV-5 and BoHV-1 infections.  相似文献   
64.
A wide range of minerals occurs in feedstuffs as naturally occurring and purposely added elements, as well as by adventitious contamination. These mineral elements can generally be classified as nutritionally essential major elements, nutritionally essential minor and trace elements, and those regarded as toxic or with an essential/toxic duality. A survey is presented of methods used for the determination of major, minor, and trace elements in feedstuffs and related biological materials. Currently available methods include the following: atomic absorption spectrometry, atomic emission spectrometry, mass spectrometry, neutron activation analysis, x-ray emission spectrometry, molecular light absorption spectrometry, molecular fluorometry, electrochemistry, Kjeldahl method (nitrogen), combustion elemental analysis, volumetry, ion chromatography, and gravimetry. Available reference, routine, official, unofficial, and recommended methods are reviewed as a basis for recommendations of methods most suitable for feedstuffs.  相似文献   
65.
An inquiry was held in 1982, 1983 and 1984 to collect information on the survival and dispersal of cucumber powdery mildew. Growers who planted a crop in December, January or February were asked when they observed mildew for the first time in their crop. A gradual increase in the number of infected crops was observed from planting until May. The earliest observations of infected crops were immediately after planting. The weeks of the first observation of mildew, the disease-free periods and the apparent rates of increase of infected crops are presented for various districts. In the districts with the highest crop density (Pijnacker), mildew was generally observed early in the growing season, while the apparent rate of increase of infected crops was higher than in other districts. In the district with the lowest crop density (Northern Netherlands), mildew was observed late in the growing season and the apparent rate of increase of infected crops was low. Possible means of survival and dispersal of inoculum are discussed. It is suggested that overwintering of inoculum is possible because cucumber plants are grown all year round. Dispersal of cucumber powdery mildew is suggested to take place by transportation of infected planting stock, visitors and wind.  相似文献   
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In 1967, 1968 and 1969 the efficacy of aerial low volume and ultra-low volume bait-spraying against Dacus oleae (Gmel.) was compared in Greece. Results were mainly assessed by periodical trapping and by post-treatment countings of the percentage of attack in sampled olives. No difference between the effect of the two methods became apparent. It is deemed necessary, however, to repeat the experiments under conditions of heavier infestation.  相似文献   
69.
Bromoxynil octanoate labelled with 14C in the ring or in the cyano-group was applied to wheat seedlings at the two-leaf or fully-tillered stage and at rates equivalent to up to 16 oz a.i./acre. The plants were grown either in environmental chambers under controlled conditions for up to 28 days, or outdoors under field conditions for various periods up to harvest. Initially, elimination of radioactivity occurred more rapidly with bromoxynil-cyano-[14C]-octanoate than with bromoxynil-ring-[14C]-octanoate, indicating metabolic attack on the cyano group. Under outdoor conditions with ring-[14C]-herbicide applied at the two-leaf stage, only 12% of the radioactivity was retained after 28 days, principally in the treated leaves. When application was made at fully-tillered stage, about 33% of the 14C was retained after 56 days, almost entirely in the treated senescent leaves at the base of the plant. There was very little translocation of the herbicide or of any major metabolite. The level of radioactivity in harvested grain and in straw more than 7.5 cm above the ground was very low, even after very late application of ring-[14C]-labelled herbicide. The amount of bromoxynil octanoate, together with any metabolite retaining part of the aromatic ring, did not collectively exceed the equivalent of approx. 0.01 parts/million bromoxynil octanoate.  相似文献   
70.
Experimental systems were produced from fragments of bracken rhizome and picloram-14C was applied to frond laminae, rhizome apices, frond buds and roots and translocation assessed 7 days after treatment. The isotope was readily taken up by all organs and freely translocated to associated fractions of the rhizome except in the case of laminae from which distribution was very poor. Accumulation of activity in the roots was considerable following treatment of the frond buds but was limited in the frond buds. Poor translocation of herbicide from treated frond laminae is considered a possible explanation of poor control in the field when bracken is sprayed in July. Lapplication du picioram e14C à la fougère Des systèmes expérimentaux ont étéétablis en utilisant des fragments de rhizome de fougére et du piciorame 14C a été appliqué sur les limbes des frondes, les apex des rhizomes, les bourgeons des frondes et les racines. La migration fut évaluée sept jours aprés le traitement. L'isotope a été facilement absorbé par tous les organes et librement transporté aux fractions correspondantes du rhizome, sauf dans le cas des limbes è partir desquels la distribution a été très faible. L'accumulation de ractivité dans les racines a été considérable è la suite du traitement des bourgeons de frondes mais a été Iimitée dans les bourgeons de frondes. Une faible migration de I'herbicide depuis les limbes des frondes est considérée comme une explication possible du désherbage mediocre auchamp, lorsque la fougère est traitée en juillet. Die Anwendung von PicIoram-14C zu Adlerfarn Aus Rhizomstücken von Adlerfarn wurden Versuchsp-flanzen gezogen und auf die Wedelspreiten, Rhizomapices, Wedelknospen und Wurzein- Picloram-14C appliziert. Die Transiokation des Herbizids wurde eine Woche nach der Behandlung gemessen. Das lsotop wurde von alien Pflan-zenorganen schnell aufgenommen und in die dem Rhizom benachbarten Pflanzenteile transloziert; bei Behandlung der Wedelspreiten war jedoch nur eine geringe Verteilung fest-zustellen. Nach Behandlung der Wedelknospen war in den Wurzein eine beträchtliche, aber in den Wedelknospen nur eine geringe Aktivitätsanreicherung feststellbar. Für den schwachen Bekämpfungserfolg des Adierfarns im Freiland bei Spritzungen im Juli, wird die geringe Transiokation des Herbizids aus den Wedelspreiten als mögliche Erklärung angesehen.  相似文献   
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