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31.
In an experiment with 12 calves, Aquacycline® in a 5 % (OTC-A5) and a 10 % (OTC-A10) solution, was compared with Terramycin®-100 (OTC-C) by injecting 20 mg OTC/kg bwt. of these preparations in the dewlap and monitoring serum concentrations as well as tissue reactions and residues at the site of injection. All 3 preparations resulted in oxytetracycline (OTC) serum concentrations above 0.5 µg/ml of approximately 60 h. During this period, OTC-A5 resulted in a 39 % and OTC-A10 in a 20 % larger area under the serum concentration-time curve, as compared to OTC-C (P < 0.05). The recorded tissue reaction in the form of swelling during the first week following injection of OTC-A5 averaged 72 % of that after OTC-C (P < 0.01), while the mean swelling after OTC-A10 was 81 % of the corresponding value after OTC-C (P < 0.05). The OTC residue levels at the sites of injection were lower after OTC-A5, but none of the preparations resulted in OTC residues exceeding 0.3 mg at 28 days and about 0.15 mg at 42 days after injection. The pathological changes at the site of injection were somewhat more pronounced in those calves which received OTC-C. Accordingly, these results give some support to the claims that Aquacycline® offers advantages with respect to absorption characteristics and tissue tolerance.  相似文献   
32.
Bone-metastasizing squamous-cell carcinoma of a 6-year-old female Bedlington terrier is reported. The dog was operated on for a squamous-cell carcinoma in the axillary region. Four weeks after operation the dog developed signs of anaemia. It also became weak and showed neurological signs. Radiographs revealed areas of rarefaction in two vertebrae and densities in the lungs suggesting tumour metastases. The animal was destroyed and metastases were found in the axillary and internal iliac lymph nodes, the lungs, the first thoracic vertebra and the third lumbar vertebra. The tumour mass in the thoracic vertebra protruded into the spinal canal and compressed the spinal cord. The tumour cells in the primary tumour were of anaplastic type. Résumé. Un carcinome squamo-cellulaire, métastasiant les os est rapporté chez un Bedlington terrier femelle de six ans. On a opéré le chien d'un carcinome squamo-cellulaire dans la région axillaire. Quatre semaines après l'opération le chien a développé des signes d'anémie. Il s'est aussi affaibli et a montré des signes neurologiques. Des radiographies ont révélé des surfaces de raréfaction dans deux vertèbres et les densités dans les poumons ont suggéré des métastases de tumeur. L'animal a été detruit et on a trouvé des métastases dans les n?uds lymphatiques, iliaques internes et axillaires, les poumons, la première vertèbre thoracique et la troisième vertèbre lombaire. L'excroissance dans la vertèbre thoracique a fait saillie dans le canal vertébral et a comprimé la moelle épinière. Les cellules de la tumeur dans la tumeur primaire étaient de type anaplastique. Zusammenfassung: Von einem Knochen-metastasierenden schuppenzelligem Karzinom in einem 6 Jahre alten weiblichen Bedlington-Terrier wurde berichtet. Man operierte den Hund an einem schuppenzelligen Karzinom in der Achsellymphdrüsengegend. Vier Wochen nach der Operation entwickelte der Hund Anzeichen von Anämie. Auch wurde er schwach und zeigte neurologische Symptome. Röntgenaufnahmen zeigten Gebiete von Rarefactio in zwei Rücken-wirbeln und Verdichtungen in der Lunge liessen auf Tochtergeschwulste deuten. Man tötete den Hund und Metastasen fanden sich in den Achsellymphdrüsen und den innerlichen Darmbein-lymphknoten, der Lunge, dem ersten Brustwirbel und dem dritten Lendenwirbel. Der Massen-tumor in dem Brustwirbel ragte bis in den Kanal der Wirbelsäule hinein und drückte auf denWirbelsäulenstrang. Die Tumorzellen in dem Primärtumor waren vom anaplastischen Typ.  相似文献   
33.
The use of self-reinforced biodegradable devices made of polyglycolide in the cancellous bone and physeal fractures of dogs and cats was compared to the use of metallic devices and external fixations on similar fractures. The series consisted of 64 dogs and 22 cats divided into 6 comparable groups. The patients in the 2 groups fixed with biodegradable devices started to use their operated limbs earlier than in the other groups. The same 2 groups also healed clinically (showed no lameness) earlier than the other groups. Radiographically there was no statistical difference between the 6 groups.On the basis of this study it may be concluded that the fixation with self-reinforced biodegradable devices is as suitable for the fixation of cancellous bone and physeal fractures of dogs and cats as the fixation with metallic devices or external fixation. This biodegradable technique has additional benefits allowing the patients to feel less pain in their operated limbs and making secondary operations to remove the devices unnecessary.  相似文献   
34.
The purpose of the study was to analyse the morphology of the equine m. articularis coxae with reference to its function during locomotion. The muscle was a constant finding in 50 horses of verying age nad sex. Different horses were selected for dissection of the muscle with its vessels and nerves, determining of length at different angles of the hip joint and weight. The muscle was shortest at maximal fexion, and the length incereased rapidly until a hip joint angle of 110°. Between 11° and maximal extension the increase in length was moderate. The mean weight of muscle was 2.7 g. Histological specimens were serially sectioned and the frequency of muscle spindles was recorded. The spindle density varied from 12 to 42 per gramme of muscel, with a mean of 26, and a mean length of the muscle spindles of 4.7 mm.
Myectomy was performed uni- or bilaterally on 5 horses to evaluate the influenceon the locomotion with no significant manges observed.
Considering the position, size, innervation and multitude of muscle spindles of the m. articularis coxae it is suggested that the muscle primarily has a receptor function inreporting on the torsion or "wrinkling" of the hip joint. The absence of manges in loconiotion of the myectomised horses indicates that the missing function of the muscle is taken over by other muscles.  相似文献   
35.
The spatial variability in the mineralisation rate of linuron [N-(3,4-dichlorophenyl)-N'-methoxy-N'-methylurea] was studied within a previously treated Danish agricultural field by sampling soils from eleven different plots randomly distributed across an area of 20 x 20 m. The soils were characterised with respect to different abiotic and biotic properties including moisture content, organic matter content, pH, nutrient content, bacterial biomass, potential for mineralisation of MCPA [(4-chloro-2-methylphenoxy)acetic acid] and linuron. Five soils had a potential for mineralisation of linuron, with 5-15% of the added [ring-U-14C]linuron metabolised to 14CO2 within 60 days at 10 degrees C, while no extensive mineralisation of linuron was observed in the six remaining soils within this period. A TLC analysis of the methanol-extractable residues showed no development of 14C-labelled metabolites from linuron in any of the samples. Multivariate analysis was conducted to elucidate relationships between the intrinsic properties of single soil samples and initial rate of linuron mineralisation. The analysis indicated that important soil parameters in determining the spatial heterogeneity included the C(total)/N(total) ratio, pH and the water-extractable potassium contents, with the first of these highly negatively correlated and the last two highly positively correlated to the initial linuron mineralisation rate. This study shows that enhanced biodegradation of linuron may develop with successive field treatments, but that considerable in-field spatial heterogeneity in the degradation rate still exists. Combined with a parallel enrichment study focused on the underlying microbial processes, the present results suggest that intrinsic soil properties affect the linuron-metabolising bacterial population and thereby determine the spatial variability in the linuron mineralisation activity.  相似文献   
36.
The effect of cereal non-starch polysaccharides (NSP) on the gut microbial populations was studied in 5 growing pigs between 39-116 kg body weight according to a Latin square design. The diets were composed to contain different NSP levels. The control diet had a normal NSP content (139 g/kg dry matter (DM)), 2 diets had a low total amount of NSP (95 and 107 g/kg DM) and 2 diets had a high amount of total NSP (191 and 199 g/kg DM). Furthermore, one of the diets within each category had a content of insoluble NSP similar to the control diet and one had a high content of insoluble NSP. Samples were collected from the ileum, via intestinal post valve T-caecum (PVTC) cannulas surgically inserted at the ileo-caecal ostium, and from the rectum. The total microbial flora of the ileal samples were analysed for by defining base pair length with terminal restriction fraction length polymorphism (T-RFLP). The microbial diversity of the coliform flora of the ileal and rectal samples were defined by biochemical fingerprinting. It was observed that many terminal restriction fragments (TRFs) disappeared when new diets were introduced and that some characteristic TRFs were found in the high and low NSP diets, respectively. Both the total gut microflora and the coliform flora were influenced by the dietary NSP content.  相似文献   
37.
The purpose of this study was to improve our knowledge concerning the epidemiology and strain diversity of Staphylococcus epidermidis isolated from bovine milk in commercial dairy herds. A total of 341 S. epidermidis isolates obtained from cows' milk (317), farmers (17) and patients (7) were characterized. Of these 105 isolates were from cows' milk in two farms, where also 17 isolates were sampled from farmers. The remaining 212 isolates from cows' milk were from 170 farms. All isolates were examined by antimicrobial susceptibility, whereas 202 were examined by pulsed-field gel electrophoresis (PFGE) and 122 by ribotyping. PFGE showed single patterns in the human strains with one exception; one strain was categorised as the same clone as four of the milk strains. PFGE divided 73 of the milk strains into 62 different patterns. The PFGE method had high discriminatory power and shows that many different S. epidermidis types exist in milk samples. Antibiotic resistance patterns matched the SmaI profiles closely in the two herds, but poorly in the routinely collected milk samples. Isolates from herd 1 showed one to five patterns, depending on the typing method used. Isolates from the milker's skin showed one pattern, which was identical to the most common pattern found in the milk isolates. Isolates from herd 2 showed three to four patterns, two of these being identical to skin isolates from the milker. As dairy cows are not a natural host for S. epidermidis the results suggest a human source of these udder infections.  相似文献   
38.
Experiments were carried out to investigate whether Potato spindle tuber viroid (PSTVd) can be transmitted intra- and inter-species from infected Solanum jasminoides to non-infected S. jasminoides and S. esculentum and from infected Brugmansia sp. to S. esculentum by Frankliniella occidentalis and Thrips tabaci by leaf sucking. The F. occidentalis experiments also included feeding on pollen prior to feeding on PSTVd-infected leaf. No thrips-mediated transmission of PSTVd was recorded. The possibility of PSTVd transmission by Apis mellifera and Bombus terrestris during their feeding/pollinating activities within ornamentals and from ornamentals to S. esculentum was included, and no bee-mediated transmission was recorded.  相似文献   
39.
Nitrogen (N) dynamic is one of the main controlling factors of responses to climate change in N-limited terrestrial ecosystems, which rely on nutrient recycling and retention. In this study we investigate the N partitioning in ecosystem compartments of a grassland heath, and the impact of multiple climate change factors on long-term N retention after 15N pulse labelling. The impacts of elevated carbon dioxide (eCO2), warming and drought and the treatments in combination on ecosystem N retention were investigated in a field scale manipulation experiment. A 6-year time-course was assessed by pulse-labelling with the stable N isotope 15N and by sampling after 1 day, 1 year and 6 years. After 6 years we observed that the total ecosystem retained 42% of the amended 15N across treatments (recovery of the amended 15N in the pool). The fate of the applied 15N was mainly stabilization in soil, with 36% 15N recovery in soil, while the plant compartment and microbial biomass each retained only 1%–2% of the added 15N. This suggests a moderate retention of N, for all treatments, as compared to similar long-term studies of forest ecosystems. A decreased ammonium and vegetation N pool combined with higher 15N retention in the soil under eCO2 treatments suggests that eCO2 promoted processes that immobilize N in soil, while warming counteracted this when combined with eCO2. Drought treatments contrastingly increased the vegetation N pool. We conclude that as the organic soil layer has the main capacity for N storage in a temperate heathland-grassland, it is important for buffering nutrient availability and maintaining a resilient ecosystem. However, the full treatment combination of drought, warming and eCO2 did not differ in 15N recovery from the control, suggesting unchanged long-term consequences of climate change on retention of pulse added N in this ecosystem.  相似文献   
40.
Genome‐wide association (GWA) mapping in potato requires high‐density genotyping. With the Illumina SolCAP potato single‐nucleotide polymorphism (SNP) array, a first tool for GWA mapping in potato became available. Thirty‐six tetraploid varieties and eight diploid breeding clones were genotyped for 8303 SNPs using this array. The objectives of our study were to examine in this set of germplasm: (i) the degree of polymorphism of the SolCAP SNPs in European germplasm, (ii) the population structure, (iii) temporal trends of genetic diversity and (iv) the genome‐wide extent of linkage disequilibrium (LD). Three‐quarters of the SNPs were polymorphic. In the principal coordinate analysis, a clear separation of tetraploid from diploid genotypes was observed, whereas no distinct subgroups among the tetraploid varieties were detected. The nonlinear trendline of the LD measure vs. the physical map distance decayed within 275 bp to an value of 0.10, indicating that theoretically, about 3 million equally distributed SNPs are required for GWA mapping in this diverse set of germplasm. As the LD decay changes with the population selected for GWA mapping, the number of required markers might be different in other germplasm.  相似文献   
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