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Neonatal respiratory distress syndrome in the calf 总被引:2,自引:0,他引:2
Thirty-five calves were delivered by caesarean section near to term. During the operation amniotic fluid was collected for determination of the lecithin/sphingomyelin (L/S) ratio. Clinical examination of the calves and analysis of blood gas concentration (venous blood) were carried out within the first hour of life. Fifteen out of 35 calves under examination did not show clinical or blood gas disorders in the course of the first hour of life. In these calves, the L/S ratio, which represents a measure for the maturity of the surfactant system, averaged 2.6. The other 20 calves, however, developed a respiratory distress syndrome together with a progressive respiratory and metabolic acidosis within the first hour of life. The L/S ratio in the animals affected with respiratory distress syndrome reached an average value of 1.5 which was significantly below that of the calves not suffering from respiratory distress. Eleven of the 20 calves which developed respiratory distress syndrome died within the first 60 hours of life. The most striking findings in the post mortem examinations of these animals were intracranial haemorrhages and pulmonary lesions (hyaline membranes, interstitial and alveolar oedema). On the basis of the significantly lower L/S ratio and the post mortem findings, it is to be assumed that the respiratory distress syndrome in calves, equally with that in infants, is attributable to a surfactant deficiency. 相似文献
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Epstein K Cohen N Boothe D Nieuwoudt C Chandler J 《Veterinary therapeutics : research in applied veterinary medicine》2004,5(2):155-167
In many cases of equine infectious disease, long-term administration of antimicrobial drugs is required. Oral agents are preferred because of the relative ease of administration compared with other routes. Enrofloxacin has been shown to be effective against a variety of equine pathogens, but oral administration of this drug has proved difficult in horses. An oral gel formulation made from the injectable cattle product produces blood levels sufficient to resolve infections caused by a variety of common equine pathogens. 相似文献
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Yao ChengZhao-Peng Shi Li-Ben JiangLin-Quan Ge Jin-Cai Wu Gary C. Jahn 《Pesticide biochemistry and physiology》2012,102(3):213-219
The chemical pesticide, imidacloprid (IMI) has long-lasting effectiveness against Hemiptera. IMI is commonly used to control the brown planthopper (BPH), Nilaparvata lugens Stål (Hemiptera: Delphacidae). Some chemical pesticides, however, can induce the susceptibility of rice to BPH, which has indirectly led to the resurgence of BPH. The mechanism of the chemical induction of the susceptibility of rice to BPH was not previously understood. Here, a 44 K Agilent Rice Expression Microarray was used to identify changes in gene expression that accompany IMI-induced rice susceptibility to BPH. The results showed that 225 genes were differentially expressed, of which 117 were upregulated, and 108 were downregulated. Gene ontology annotation and pathway analysis revealed that differentially expressed genes were mainly classified into the eight functional groups: oxidation reduction, regulation of cellular process, response to stress, electron carrier activity, metabolic process, transport, signal transducer, and organismal development. The genes encoding plant lipid transfer protein, lignin peroxidase, and flavonol-3-O-methyltransferenase may be important responses to the IMI-induced susceptibility of rice to BPH. The reliability of the microarray data was verified by performing quantitative real-time PCR and the data provide valuable information for further study of the molecular mechanism of IMI-induced susceptibility of rice. 相似文献
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The occurrence of sleep disorder in three half sibling Lipizzaner is described. Sleepiness, swaying, stumbling, carpal joints buckling and falling down onto the carpal joints had been present since early foal age in all of them. Clinical signs had gradually reduced since the age of 2 years in cases 1 and 3. Sleepiness was induced by going out from the stable in adulthood. A physostigmine test was performed in all three affected horses and produced positive results in cases 1 and 3. The result of the test in case 2 was unclear due to the almost continuous sleepiness of the foal. Hypocretin-1 concentration in the cerebrospinal fluid was established using a standardised radioimmunoassay in case 1 (317.85?pg/mL), case 2 (303.43?pg/mL) and five adult control horses (275.2?±?47.9 [SD] pg/mL) and was considered as normal in all horses. The sire of the affected horses has had 19 other registered offspring who did not show clinical signs of sleep disorder and also dams of all three cases produced healthy foals. Based on the demographic and clinical data together with the responses to the physostigmine challenges, the diagnosis of familial equine narcolepsy was made. 相似文献
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Diseases caused by members of the Potyviridae family currently threaten pepper crops (Capsicum annuum L.) worldwide. A series of monogenic recessive resistance genes that control potyvirus resistance at the pvr1 locus in Capsicum species are widely known and used in pepper breeding programs, each allele with a differential resistance spectrum affecting a distinct range of viral strains across three viruses, Tobacco etch virus (TEV), Pepper mottle virus and Potato virus Y. In this study, we systematically analyzed the resistant spectra, and the level of the resistance each allele confers using a set of pepper genotypes homozygous or heterozygous for the following alleles; Pvr1 +, pvr1, pvr1 1 and pvr1 2. The resistance alleles at the pvr1 locus show recessive inheritance when combined with a susceptible allele in F1 progenies. However, our results show that resistance in this system is, in fact, not always fully recessive and establish a hierarchy of allelic interactions We identified the resistance phenotype in F1 progenies generated by combining a complete resistant allele with an incomplete resistance allele against TEV strains implying that the resistance alleles at the pvr1 shows dominant inheritance when combined with an incomplete resistance allele. Resistance alleles against TEV-HAT, pvr1 and pvr1 2, show dominance inheritance when each is combined with pvr1 1. The resistance allele, pvr1, shows dominance inheritance when combined with pvr1 2 against TEV-N. These results clarify the allelic relationship between resistance alleles at the pvr1 locus displaying different resistance spectra, and will assist breeders to select the preferred combinations of the resistance alleles to obtain durable resistance against multiple potyviral strains. 相似文献