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51.
Quantitative phytochemical variation was determined from roots and inflorescences of native plant populations in the genus Echinacea. Specimens were collected in situ throughout the natural range of each putative taxon and transplanted to greenhouse cultivation. Ethanolic extracts from individual plants were separated by reversed-phase HPLC to quantify the alkamides, polyenes/ynes, and phenolics, and then grouped by age and taxonomically, according to a recent morphometric taxonomic revision of the genus. Canonical discriminant analysis revealed that cichoric acid, the diene alkamides 1-3 and 7, and ketoalkene 24 were the best taxonomic markers. Mean content for each of 26 phytochemicals revealed useful agronomic information, such as those varieties and organs with the highest accumulations, as well as the optimal age and growth conditions for each variety. The highest amounts of cichoric acid were measured from the older, wild inflorescences of E. pallida var.sanguinea, whereas the highest quantities of the alkamides 1-3 and 7 were present in roots of wild and transplanted E. purpurea. Baseline phytochemical data and chromatographic profiles for all types of wild Echinacea may be used for protection of wild stands, germplasm identification, and crop improvement.  相似文献   
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SUMMARY Four dogs with disseminated aspergillosis caused by Aspergillus terreus were treated with oral itraconazole for 190 to 1095 days. Infection was eliminated in 1 dog. Two dogs were treated for 1000 and 1095 days but were eventually euthanased 572 and 485 days after treatment was stopped. At necropsy both dogs had widespread aspergillosis. The fourth dog was euthanased for other reasons after 190 days of treatment when it was showing a good clinical response although there was radiographic evidence that the disease was progressing.  相似文献   
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In this paper we report the development and testing of a fowlpox virus vector system. Insertion sites in non-essential regions within the terminal inverted repeats of the virus have been characterised. Foreign genes inserted into these sites are shown to be present in two copies in the resultant recombinant virus. To test the potential use of this vector as a live vaccine the fusion gene of Newcastle disease virus (NDV) has been inserted into a vaccine strain of fowlpox virus, and inoculated into chickens. The experiments demonstrate the ability of the recombinant to protect chickens against challenge by a virulent strain of NDV and to elicit the formation of anti-fusion protein antibody.  相似文献   
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Sheep antibodies against a pig E-rosette-forming lymphoblastic T lymphoma raised by two intravenous injections of 10(10) cells showed little lymphocytotoxic activity which could be absorbed with red cells, alveolar macrophages or kidney or liver cell homogenates. Bone marrow absorption yielded subpopulation specific antibody which binds to E rosette-forming cells (E.RFC) using either complement-mediated cytotoxicity or indirect antiglobulin rosette formation. In 30 blood lymphocyte preparations from 20 pigs with a range of approximately 20-85% E rosettes the mean E% 43.5 +/- 2.7 agreed with the % antigen+ cells by cytotoxicity mean = 42.6 +/- 2.7 and in each individual sample these figures also agreed closely. In samples of blood lymphocytes enriched and depleted for E rosettes, results of %E+ also agreed closely with % antigen+ cells. This relationship also held for thymocytes and the specific antibodies could be completely absorbed with thymocytes. These data show that the antibody identified peripheral and thymic E.RFC. Bound to lymphocytes the antibody inhibited E rosette-formation with sheep red blood cells (SRBC) in saline (S) and dextran (DS) and with pig RBC in dextran and in Ficoll, but did not affect B cells shown by immunofluorescence, direct antiglobulin rosette formation or Fc rosette-formation, either in saline or dextran, (which include T gamma cells). E rosette inhibition was dependent on antibody concentration, showing single and double sigmoid curves for S and DS rosettes respectively, consistent with differing ease of inhibition of the strong and weak rosette formation. The same spectrum of inhibition of rosette formation by antibody binding followed subsequent incubation with C'6-deficient rabbit serum, but with C'-sufficient serum resulted in loss of cells which require dextran for Fc rosette-formation (T gamma). Thus the serum reveals E rosette-forming T cells and their subpopulations, perhaps by binding to the SRBC receptor.  相似文献   
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The efficacy of emulsifiable concentrate and dust formulations of pirimiphos-methyl and etrimfos were assessed, when admixed with oilseed rape, 1 day after treatment, against susceptible beetle, moth and mite species. The minimum intended doses required to provide complete mortality differed with each pest species. If Maximum Residue Limits are introduced that are equivalent to less than one quarter of the current pesticide application rates, their effective use may be prevented, as control of Acarus siro and Tyrophagus putrescentiae may not be achieved.  相似文献   
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AIMS: The aims of this study were (a) to evaluate the effect of xylazine and tolazoline, with and without lignocaine, on the cortisol response of calves following amputation dehorning and (b) to assess the effect of a non-steroidal anti-inflammatory drug (ketoprofen) and local anaesthesia on the cortisol response of calves to amputation dehorning.

METHODS: Plasma cortisol concentrations were measured in 100 dehorned or non-dehorned 3-month-old calves over an 8-h period following five different sedative/analgesic or control treatments. Sedative/analgesic treatments were: control (no anaesthesia); local anaesthesia and ketoprofen; local anaesthesia and xylazine; local anaesthesia, xylazine and tolazoline; and xylazine only. Within each sedative/analgesic treatment group, half the calves (n=10 per group) were amputation dehorned and half were not dehorned.

RESULTS: The change in plasma cortisol concentrations in calves dehorned after being given ketoprofen and local anaesthesia did not differ significantly from that of non-dehorned control calves for at least 8 h. In contrast, the cortisol response of dehorned calves not given analgesic drugs peaked 30 min after dehorning and lasted >4 h. Xylazine injected before dehorning significantly reduced but did not eliminate the peak of the cortisol response. When both xylazine and local anaesthesia were administered before dehorning the peak in the cortisol response was virtually eliminated. In the dehorned calves that received xylazine with or without local anaesthesia, cortisol concentration increased significantly 3 h after dehorning and did not return to baseline until at least 5 h later. When tolazoline was administered shortly after xylazine, it caused a marked cortisol response, higher than the response to any other treatment.

CONCLUSIONS: Combining ketoprofen and local anaesthesia minimised the cortisol response, and by inference the pain- induced distress, following amputation dehorning in calves. Xylazine reduced the initial cortisol response to dehorning but not as much as when local anaesthesia was also given. The increase in cortisol concentration from 3–8 h after dehorning in calves given xylazine alone or in combination with local anaesthesia suggests that calves experienced pain-induced distress during this time and that xylazine had no long-term analgesic effect. Tolazoline, used to reverse the sedative effects of xylazine, caused a marked cortisol response in calves via a mechanism which remains unclear.  相似文献   
60.
Eosinophilic cells accumulate in the capillaries of the bovine Graafian follicle shortly before ovulation and in the early developing corpus luteum (CL). Suppressing the migration of these eosinophilic cells by dexamethasone allowed us to evaluate their possible function in the CL development. Brown Swiss cows (n = 10) were randomly subdivided into two groups (n = 5). Every group was used once as control group and once as experimental group with two oestrous cycles between each treatment. Eighteen hours (h) after oestrus synchronization, dexamethasone or saline was given. Ovulation was induced 24 h later with gonadotropin‐releasing hormone. Another injection of dexamethasone or saline was given 12 h later. Eosinophilic cells in the blood were counted daily until day 7 after the first dexamethasone injection. The collection of ovaries took place at days 1, 2 and 5. Gene expression, protein concentration and location of angiogenic factors, chemokines, insulin‐like growth factor 1 (IGF1) and eosinophilic cells were studied. No eosinophilic cells were found in the CL of the treatment group. Blood progesterone decreased significantly in the dexamethasone group from day 8 to 17. The protein concentration of FGF2 increased significantly in CL tissue at day 2 and VEGFA decreased. Local IGF1 gene expression in the CL was not regulated. We assume from our data that the migration of eosinophilic cells into the early CL is not an essential, but an important stimulus for angiogenesis during early CL development in cattle.  相似文献   
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