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41.
Transesophageal echocardiography (TEE) enhances our ability to see the patent ductus arteriosus in the dog. The improved visualization may potentially improve our ability to perform transcatheter coil embolization in patients that are more likely to have a successful outcome. This report uses still and video images to detail the specifics of coil embolization as performed with the assistance of TEE and compares the images with those of angiography, surgery and postmortem examination.  相似文献   
42.
The Mars Global Surveyor (MGS) z-axis accelerometer has obtained over 200 vertical structures of thermospheric density, temperature, and pressure, ranging from 110 to 170 kilometers, compared to only three previous such vertical structures. In November 1997, a regional dust storm in the Southern Hemisphere triggered an unexpectedly large thermospheric response at mid-northern latitudes, increasing the altitude of thermospheric pressure surfaces there by as much as 8 kilometers and indicating a strong global thermospheric response to a regional dust storm. Throughout the MGS mission, thermospheric density bulges have been detected on opposite sides of the planet near 90 degreesE and 90 degreesW, in the vicinity of maximum terrain heights. This wave 2 pattern may be caused by topographically-forced planetary waves propagating up from the lower atmosphere.  相似文献   
43.
Objective To provide serological data to support Australia's claim of freedom from porcine reproductive and respiratory syndrome.
Design A national serological survey was designed to provide 99% confidence of detecting at least one infected pig herd in Australia, assuming that at least 5% of herds would have been exposed to porcine reproductive and respiratory syndrome virus and that at least 25% of the 'finisher' pigs in these herds would have antibodies to the virus.
Procedure A two-stage testing regime was used. All samples were tested with a commercially available enzyme-linked immunosorbent assay. If assay reactions were found, all samples from the herd were to be tested using the indirect immunofluorescence antibody assay.
Results Of the 875 samples from 163 herds from all States in Australia, there was some evidence of reactivity in only four samples from four herds on the enzyme-linked immunosorbent assay. Further testing using the indirect immunofluorescence antibody assay according to the study protocol demonstrated that the reactions were not due to the presence of specific porcine reproductive and respiratory syndrome virus antibodies in the sera.
Conclusion The results of this study support the view that Australian pigs are free of porcine reproductive and respiratory syndrome virus.  相似文献   
44.
SUMMARY Weaned lambs were infected with Haemonchus contortus 35,28,21,14 and 7 days after treatment with moxidectin at 0.2 mg/kg and 35 and 14 days after treatment with ivermectin at the same dose rate. Worm counts 14 days after infection showed that moxidectin prevented the establishment of over 99% of infective larvae for 28 days and reduced the establishment rate at 35 days by 96%, relative to ivermectin. There was no difference in the protective efficacy of ivermectin at 14 or 35 days. The persistence of moxidectin is likely to provide advantages in nematode control, particularly when used as a strategic early summer treatment or as a pre-lambing treatment to ewes. Implications of the persistent activity of moxidectin for the development of resistance during the decay phase are discussed.  相似文献   
45.
Objectives of this study were to characterize patterns of follicular development in sheep superovulated with purified follicle stimulating hormone (FSH) (OVAGENTM, ICP, Auckland, New Zealand) and to determine its influence on preovulatory events (onset of the oestrus behaviour and timing of the preovulatory luteinizing hormone surge) and ovarian response (ovulation rate and embryo yield). Number and size of all ≥ 23 mm follicles from the first FSH injection to withdrawal of progestagen sponges was determined by transrectal ultrasonography just prior to every FSH injection in nine Manchega ewes superovulated with eight decreasing doses (ml) (1.5 × 3, 1.25 × 2 and 1 × 3) of OVAGEN injected twice daily from 60 h before to 24 h after the withdrawal of 40 mg fluorogestone acetate sponges. Oestrous detection and jugular blood sampling for LH radioimmunoassay were performed every 3 h from 14 to 53 h after sponge removal and ovulation rate and number of embryos were determined 4 days after progestagen withdrawal. Administration of OVAGEN induced a significant rise (p < 0.0005) in the number of follicles ≥ 4 mm in size because of an increased growth in size of follicles from the first FSH injection to sponge removal, an increase in the number of newly detected follicles from 12 to 36 h of the first FSH dose (p < 0.005) and a decrease in regression rate from 24 h (p < 0.001). The number of follicles 2–3 mm in size at first FSH dose (10.4 ± 1.5) was positively correlated with the number of ≥ 4 mm follicles at 0 h (19.0 ± 2.7, p < 0.01). A higher number of ≥ 4 mm follicles at 0 h was related with an earlier appearance of oestrus (31.5 ± 1.5 h, p = 0.08) and LH surge (45.0 ± 2.3 h, p < 0.005), and a higher ovulation rate (18.2 ± 3.8, p < 0.005). On the other hand, the rate of embryo recovery was decreased in ewes with earlier preovulatory LH peaks (p < 0.005), with a shorter interval between oestrus and LH peak (p < 0.05).  相似文献   
46.
47.
蛋白多肽二级结构的电脑预测表明,非洲猪瘟病毒(MalawiLIL20/1株)k8R基因编码带有多个疏水氨基酸小区的27kDa蛋白质。该基因的PCR产物克隆入质粒pGEX-2T后,在大肠杆菌中表达42~54kDa不溶性GST-k8R融合蛋白。此表达蛋白能被针对不同非洲猪瘟病毒株的猪免疫血清识别。在非洲猪瘟病毒细胞适应株感染的细胞中,针对k8R大肠杆菌表达产物的单抗能检测出27kDa特异病毒蛋白。进一步鉴定表明,k8R基因编码的蛋白质为病毒非结构蛋白,不发生糖基化,出现于病毒感染周期的晚期,主要集中于靠近细胞核的病毒复制部位。用大肠杆菌表达的GST-k8R融合蛋白免疫猪未能抵抗MalawiLIL20/1强毒株攻击。  相似文献   
48.
Objectives To define the prevalence of Bartonella spp., Rickettsia felis, Mycoplasma haemofelis, ‘Candidatus Mycoplasma haemominutum’ (Mhm) and ‘Candidatus Mycoplasma turicensis’ (Mtc) in cats and their fleas in eastern Australia. Design and procedure Conventional PCR assays that detect Bartonella spp., M. haemofelis, Mhm, Mtc, Rickettsia spp., Ehrlichia spp., Anaplasma spp. and Neorickettsia spp. were performed on DNA extracted from blood and fleas collected from 111 cats. Cat sera were assayed by ELISA for IgG of Bartonella spp. Results DNA of M. haemofelis, Mtc and Mhm was amplified from 1 (0.9%), 1 (0.9%) and 17 cats (15.3%), respectively. Only DNA of Mhm was amplified from the 62 of 111 pooled flea samples (flea sets; 55.9%). Overall, the prevalence rates for Bartonella spp. DNA in the cats and the flea sets was 16.2% (18 cats) and 28.8% (32 flea sets), respectively. Bartonella spp. IgG was detected in 42 cats (37.8%), of which 11 (26.2%) were positive for Bartonella spp. DNA in their blood. R. felis DNA was amplified from 22 flea sets (19.8%), but not from cats. Overall, DNA of one or more of the organisms was amplified from 27% (30) of cats and 67.6% (75) of the flea sets. Conclusions This is the first Australian study to determine the prevalence of R. felis and B. clarridgeiae in both fleas and the cats from which they were collected. Flea-associated infectious agents are common in cats and fleas in eastern Australia and support the recommendation that stringent flea control be maintained on cats.  相似文献   
49.
Objective: To assess the efficacy and safety of a formulation containing moxidectin and 6 in 1 vaccine in sheep under field conditions.
Design: Efficacy and safety study.
Animals: Two hundred and five crossbred Merino lambs and two hundred and eight Merino ewes were used in the studies.
Procedure: A formulation was made for the simultaneous treatment of sheep with moxidectin and immunisation against clostridial diseases and caseous lymphadenitis. The efficacy against nematodes, vaccine response and safety were assessed.
Results: Effective control of nematodes and responses to antigens were achieved following subcutaneous administration. The formulation was safe to administer; occasional minor tissue reactions were evident, but no other adverse effects of treatment were observed in either pregnant ewes or lambs, using either the recommended dose, or an overdose of the formulation.
Conclusion: Administration of a formulation containing moxidectin, five clostridial antigens and caseous lymphadenitis antigen proved safe and efficacious under field conditions.  相似文献   
50.
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