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91.
Nude mice were injected subcutaneously with disrupted cells from three continuous cell lines (HeLa, NCTC clone 2472 and Morris hepatoma). No tumours were observed at either the inoculation site or in other organs taken at 35 or 90 days after injection. Live cells from one line (HeLa) produced tumours at the inoculation site after eight to 12 days.  相似文献   
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Bronchoalveolar lavage samples were collected using a fibreoptic endoscope from horses at specified times before and after single bouts of exercise. Lucigenin-dependent phagocytic chemiluminescence was used to assess the effect of exercise on the alveolar macrophage metabolic activity in response to stimulation by opsonised zymosan. A profound suppressive effect on the chemiluminescence production was present throughout the first three days after exercise. However, the cellular composition of lavage fluids was not altered by the exercise. It is suggested that strenuous exercise may jeopardize the antimicrobial function of alveolar macrophages which may lead to an increase in susceptibility to infection.  相似文献   
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The depression of response of Brucella abortus strain 19 caused by an infectious bursal disease vaccine virus given to chicks at one day old was shown to persist for four weeks. Histological examination of the bursa of Fabricius showed a gradual repopulation by bursal lymphocytes, after initial damage, concomitant with the development of a humoral response.  相似文献   
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OBJECTIVE: To evaluate the effectiveness of four ketamine-based anaesthetics in badgers using a quantitative anaesthesia assessment technique. STUDY DESIGN: Prospective randomized 'blinded' experimental trial. METHODS: The quality of induction, of anaesthesia (at 5-minute intervals) and of recovery were assessed in 93 badgers, given either one of three ketamine (K)-medetomidine (M)-butorphanol (B) combinations: group A - M K B at 20/40/80 microg kg(-1); group B - M K B at 20/40/60 microg kg(-1); and group C - M K B at 20/60/40 microg kg(-1), or ketamine (K) alone at 2 mg kg(-1) (group D). The assessor was ignorant of the combination administered. Physiological variables (heart and respiratory rates and rectal temperature) were measured at 5-minute intervals during anaesthesia. Gingival mucus membrane colour was also recorded. RESULTS: Induction to anaesthesia was most rapid with ketamine (2 mg kg(-1)) although induction quality did not differ between techniques. Ketamine used alone gave the poorest score for anaesthesia quality. Heart rate (HR) and scores for gingival mucus membrane colour were higher in animals anaesthetized with ketamine alone. Rectal temperature did not differ significantly between the techniques at any time during anaesthesia. Ketamine used alone produced the poorest quality of recovery. CONCLUSION AND CLINICAL RELEVANCE: The M-K-B combinations investigated overcame several side effects associated with ketamine anaesthesia, but at the expense of more variable induction times, lower HRs, and poorer mucus membrane coloration.  相似文献   
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ABSTRACT A murine hybridoma cell line GD2 secreting an immunoglobulin (Ig)M monoclonal antibody (MAb) was produced against surface antigens from an anastomosis group (AG) 4 isolate of Rhizoctonia solani (teleomorph: Thanatephorus cucumeris). Ascites were produced in mice using GD2 hybridoma cells and used to develop a rapid immunochromatographic lateral flow device (LFD) for the detection of antigens from R. solani and certain related Rhizoctonia spp. The LFD was tested for specificity against surface antigens from related and unrelated soil fungi. Antigens from representative isolates of R. solani AGs 1, 2-1, 2-3, 2-t, 3, 4, 5, 6, 7, 8, 9, 10, 11, and BI gave a positive response in LFD tests, as did antigens from Thanatephorus orchidicola, T. praticola, R. fragariae (teleomorph: Ceratorhiza fragariae), Ceratorhiza goodyerae-repentis, Ceratobasidium cornigerum, and binucleate AGE. Antigens from R. solani AGs 2-2, 2-2IIIB, and 2-2IV and from the related fungi R. carotae, R. cerealis (teleomorph: Ceratobasium cereale), R. crocorum (teleomorph: Helicobasidium brebissonii), R. oryzae (teleomorph Waitea circinata), and R. zeae gave negative responses, as did antigens from a range of unrelated fungi and oomycetes including Fusarium, Gliocladium, Trichoderma, Pythium, and Phytophthora spp. The usefulness of the LFD to detect R. solani was demonstrated in soils naturally infested with R. solani AG3. There was close agreement between results of LFD tests and conventional plate enrichment tests employing selective medium. The specificity of the technique was confirmed by polymerase chain reaction PCR using R. solani AG3-specific primers and by analyses based on sequences of the internal transcribed spacer (ITS)1-5.8S-ITS2 rRNA-encoding regions of unrelated fungi recovered from soil samples. The LFD was used to quantify R. solani AG4 in artificially infested soil samples (chopped potato soil inoculum). Estimates of CFU per gram of soil were derived using a most-probable number technique, which was based on the presence or absence of a detectable signal in the LFD. Estimates of CFU obtained in LFD tests and those obtained in a plate-trapped antigen enzyme-linked immunosorbent assay incorporating MAb GD2 were identical (449 CFU g(-1) of soil).  相似文献   
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OBJECTIVE: To determine if the microclimate is detrimental to horses during international air transportation in an enclosed container. PROCEDURE: On each of two 12 h and two 24 h flights three horses were transported in an enclosed container designed to prevent exposure to insect vectors. Heart rates were monitored throughout and blood samples were collected periodically. Air in the container was sampled for bacteria and fungal spores and the temperature and relative humidity were recorded inside and outside the container periodically during the flight. On the two 12 h flights similar observations were made on three horses transported in regular open containers, which were used as controls. RESULTS: Heart rates during the flights reflected any agitation of the horses. Agitation was only mild and generally associated with take-off and landing. There were no changes in haematological or blood biochemical values that suggested any detrimental effects of the flights. The temperature in the Airstable was relatively constant during each flight (means ranged from 18.7 to 23.4 degrees C) and was significantly warmer than in the cargo hold (range 13.9 to 18.3 degrees C). Relative humidity fluctuated more widely and reflected the ambient humidity during airport stops. The numbers of bacteria and fungal spores in the Airstable air varied during the flights but were of no apparent significance to the horses' health. CONCLUSION: The Airstable proved a convenient means to transport horses on international flights and caused no discernible ill effects on the horses studied.  相似文献   
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