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941.
New evidence is presented to support the contention that the amoeba/cyst colonies isolated from surface-sterilized Spongospora subterranea f.sp. subterranea -infected potato tubers and spore balls have a saprophytic phase but are contaminants and not S. subterranea. Amoebae isolated from infected tissues and spore balls formed colonies associated with bacteria on 1% water agar at 18°C and encysted after 5–7 days. These cysts were morphologically distinct from the resting spores of S. subterranea and were formed singly or in a layer, unlike the spore ball (cystosorus) of S. subterranea . Amoebae, cysts and mixtures of amoebae and cysts in primary, secondary and tertiary subcultures failed to infect tomato roots. PCR amplification of DNA from amoebae, cysts and spore balls using the S. subterranea -specific primer pair SsF/R generated a 434-bp product from S. subterranea spore balls only and not from amoebae or cysts. When an amoeba/cyst-specific primer pair AmF/R was designed and used for PCR amplification, a single 411-bp product was generated from DNA of amoebae and cysts, but not from DNA of S. subterranea spore balls. These results are discussed in relation to earlier reports claiming the successful isolation of S. subterranea and other plasmodiophorids in vitro . 相似文献
942.
Calcium, magnesium, copper, inorganic phosphorus, sodium, potassium, total protein, albumin, globulin, urea, glucose, packed cell volume and haemoglobin in the bloods of apparently health single-suckler calves were frequently measured. Values were within normal ranges except magnesium and copper which became subnormal as lactation advanced and closely approached values of single-suckler calves clinically affected with combined hypomagnesaemic tetany and hypocuprosis which responded to magnesium and copper therapy.
Kurzfassung Die Autoren bestimmten häufig den Gehalt von Kalzium, Magnesium, Kupfer, anorganischem Phosphor, Natrium, Kalium, gesamtem Protein, Eiweiss, Globulin, Harnstoff, Glukose, Hämatokrit und Hämoglobin im Blut anscheinend gesunder Saugkälbern. Die bestimmten Werte lagen im je mehr die Laktation weiterschritt, und näherten sich den Werten von Saugkälbern, die von dem gleichzeitig auftretenden Magnesium und Kupfermangel im Blut verursachtem Starrkrampf befallen waren, und die auf eine Magnesium und Kupfer-Thermapie reagieriten.
Resume Le calcium, le magnésium, le cuivre, le phosphore inorganique, le sodium, le potassium, les proteines totales, les albumines, les globulines, l'urée, le glucose, le hématocrite et l'hémoglobine dans le sang de veaux allaités et apparemment en bonne santé ont été mesurés. Les valeurs no dépassaient pas les limites normales sauf dans le cas du magnésium et du cuivre, qui devenaient subnormales au fur et à mesure que la période de lactation avancait, pour se rapprocher aux valeurs des veaux allaités atteints cliniquement d'une combination de la tétanie hypomagnésémique et al l'hypocuperose que réagissent à une thérapie de magnésium et de cuivre.
Riassunto Gli autori hanno spesso definito il contenuto in calcio, magnesio, rame, fosforo inorganico, sodio potassio, proteina totale albumina, globulina, urea, glucosio, ematocrita, ed ematoglobulina del sangue di vitelli poppanti apparentemente sani. I valori erano normali eccetto quelli del magnesio e del rame che diventarono subnormali man mano che progrediva la lattaxione ed avvicinarono i valori dei vitelli lattanti clinicamente affetti dalla tetania ipomagnesemica combinata alla ipocuperosi e che rispondevano ad una terapia con magnesio e rame.相似文献
943.
Ana M. Guti��rrez Jos�� J. Cer��n Blas A. Marsilla Mar��a D. Parra Silvia Martinez-Subiela 《Canadian journal of veterinary research》2012,76(2):136-142
A new method was developed to simultaneously measure 2 acute-phase proteins (APPs) by time-resolved immunofluorometry. The assay, based on double-label quantification of haptoglobin (Hp) and C-reactive protein (CRP) in meat juice samples from pigs, was constructed by use of a combination of europium and samarium chelate lanthanides as labels. Meat juice samples from 154 pigs were used for analytic and clinical validation of the assay through determination of precision, accuracy, limit of detection, and quantification. The analytic performance of the assay was satisfactory, with good intra-assay and interassay precision and accuracy. The levels of Hp and CRP were increased in the meat juice samples of diseased animals compared with healthy ones. According to the results, higher sensitivity could be achieved if the cut-off values of both proteins were taken into account for clinical relevance rather than used individually. Since the dual assay saved both time and sample, it could be used as a rapid and sensitive screening test in porcine production. 相似文献
944.
Autochthonous Chagas disease in the southern United States: A case report of suspected residential and military exposures 下载免费PDF全文
N. Harris L. Woc‐Colburn S. M. Gunter R. Gorchakov K. O. Murray S. Rossmann M. N. Garcia 《Zoonoses and public health》2017,64(6):491-493
Chagas disease is a parasitic infection that can result in a progressive dilated cardiomyopathy. Here, we present the epidemiologic details of a suspected locally acquired transmission case originating from the southern United States. This is the first published report of Chagas disease in a young, healthy United States veteran with repeat triatomine exposures in Arizona. Military personnel and Arizona residents should be aware of their Chagas disease transmission risks. 相似文献
945.
Molina R Galina CS Maquivar M Estrada S Chávez A Díaz GS 《Veterinary research communications》2003,27(8):671-680
In order to evaluate the reproductive effect of a rotational breeding system, the pregnancy rate of 69 Zebu cows was assessed, 32 late postpartum (211±93 days postpartum, LP) and 37 early postpartum (averaging 63±8 days after calving, EP). In the LP group, 60% (19/32) were cycling before exposure to the bulls but only 38% (14/37) in the EP group. The two groups were dissimilar from the start (p<0.05). The cows were exposed in a rotational breeding system, with six Brahman bulls with previous sexual experience paired off in three groups (A–B, C–D and E–F). The cows were exposed to each pair of bulls for a period of 3 weeks, with one week in between each period, when the females were without the presence of a male. In the LP group, the pair of bulls A–B obtained a pregnancy rate of 72% (23/32), whereas for bulls C–D the pregnancy rate was 33% (3/9) and for bulls E–F the pregnancy rate was 67% (4/6). In contrast, for the EP cows, bulls A–B obtained a pregnancy rate of 32% (12/37), bulls C–D a pregnancy rate of 67% (12/18) and for bulls E–F a pregnancy rate of 55% (6/11). The percentage pregnancy obtained using the pair of bulls A–B differed (p<0.05) between LP and EP, whereas for bulls C–D and E–F it was similar. The pregnancy rate was different (p<0.05) in the first 3 weeks of mating for the LP group, the highest number of cows becoming pregnant during the first 3 weeks of the study. In contrast, the highest number of pregnancies in EP occurred evenly during the last 6 weeks. This study suggests that the reproductive performance of pairs of bulls in a 9-week rotational programme with the overall pregnancy rate is similar (94% in the LP and 81% in the EP). However, the time taken for the females to become pregnant, and hence the performance of the bulls, is related to the average number of days postpartum for the cows. 相似文献
946.
947.
In vitro techniques have been developed to study the invasive processes of Fasciola gigantica. The conditions necessary for excystment were identical with those required by F hepatica. The ability of larvae to penetrate mouse gut in vitro was influenced by the composition of the fluid within the gut, and by the region of gut wall to which the larvae were exposed. Larvae remained viable on spleen cell monolayers for at least 60 days. 相似文献
948.
949.
The unique challenges that laboratories in Queensland and New South Wales faced during the response to the 2007 equine influenza outbreak and how these were managed are described. 相似文献
950.
The objective of this study was to establish a cryopreservation protocol for hawthorn shoot apices (Crataegus pinnatifida Bge.). Cryopreservation was carried out via encapsulation–dehydration, vitrification, and encapsulation–vitrification on shoot apices excised from in vitro cultures. We began by showing that cold-acclimation enhanced the regrowth of cryopreserved apices from 10.0 to 65.5% in encapsulation–dehydration. We then decided that the encapsulation–dehydration method was an optimal cryopreservation method for hawthorn shoot apices in terms of its high recovery after cryopreservation as well as its ease of use compared with vitrification and encapsulation–vitrification. In encapsulation–dehydration, the protocol leading to optimal regrowth was as follows: after cold-acclimation at 5 °C in the dark for 2 weeks, excised shoot tips were pretreated for 24 h at 25 °C on hormone-free Murashige and Skoog [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassays with tobacco tissue culture. Physiol. Plant. 15, 473–497] (MS) basal medium with 0.4 mol/L sucrose, then encapsulated and precultured in liquid MS medium with 0.8 mol/L sucrose for 16 h at 25 °C. Precultured beads were dehydrated for 6 h at 25 °C in the dessicator containing 50 g silica gel to a moisture content of 15.3% (fresh-weight basis) before cryostorage for 1 h. In addition, we examined the effect of adding glycerol to both the alginate beads and loading solution to enhance regrowth after cryopreservation in encapsulation–dehydration. In the present study, it was shown that adding 0.5 mol/L glycerol resulted in high regrowth percentages (82.5–90.0%) in four Crataegus species. 相似文献