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441.
Joao H.N. Soares Christina Braun Marcela L. Machado Renato L. Oliveira Natalia Henao-Guerrero Sherryl Countermash-Ott Irving C. Allen David C. Grant Antonio Giannella-Neto 《Veterinary anaesthesia and analgesia》2021,48(3):324-333
ObjectivesTo compare pulmonary gas exchange, tissue oxygenation and cardiovascular effects of four levels of end-expiratory pressure: no positive end-expiratory pressure (ZEEP), positive end-expiratory pressure (PEEP) of maximal respiratory system compliance (PEEPmaxCrs), PEEPmaxCrs + 2 cmH2O (PEEPmaxCrs+2), PEEPmaxCrs + 4 cmH2O (PEEPmaxCrs+4), in isoflurane-anesthetized dogs.Study designProspective randomized crossover study.AnimalsA total of seven healthy male Beagle dogs, aged 1 year and weighing 10.2 ± 0.7 kg (mean ± standard deviation).MethodsThe dogs were administered acepromazine and anesthesia was induced with propofol and maintained with isoflurane. Ventilation was controlled for 4 hours with ZEEP, PEEPmaxCrs, PEEPmaxCrs+2 or PEEPmaxCrs+4. Cardiovascular, pulmonary gas exchange and tissue oxygenation data were evaluated at 5, 60, 120, 180 and 240 minutes of ventilation and compared using a mixed-model anova followed by Bonferroni test. p < 0.05 was considered significant.ResultsCardiac index (CI) and mean arterial pressure (MAP) were lower in all PEEP treatments at 5 minutes when compared with ZEEP. CI persisted lower throughout the 4 hours only in PEEPmaxCrs+4 with the lowest CI at 5 minutes (2.15 ± 0.70 versus 3.45 ± 0.94 L minute–1 m–2). At 180 and 240 minutes, MAP was lower in PEEPmaxCrs+4 than in PEEPmaxCrs, with the lowest value at 180 minutes (58 ± 7 versus 67 ± 7 mmHg). Oxygen delivery index (DO2I) was lower in PEEPmaxCrs+4 than in ZEEP at 5, 60, 120 and 180 minutes. Venous admixture was not different among treatments.Conclusion and clinical relevanceThe use of PEEP caused a transient decrease in MAP and CI in lung-healthy dogs anesthetized with isoflurane, which improved after 60 minutes of ventilation in all levels of PEEP except PEEPmaxCrs+4. A clinically significant improvement in arterial oxygenation and DO2I was not observed with PEEPmaxCrs and PEEPmaxCrs+2 in comparison with ZEEP, whereas PEEPmaxCrs+4 decreased DO2I. 相似文献
442.
Red clover (Trifolium pratense L.) is the third major forage species in Europe, but there is limited information on the biodiversity and the genetic structure
of landraces and natural populations which evolved in this region. The objective of this study was producing such information
for Italian germplasm on the ground of molecular and morphophysiological diversity. The study included 16 Italian natural
populations from a wide range of environments, four landraces representing the four traditional commercial ecotypes, and two
varieties. Eight morphophysiological traits were assessed in a replicated trial under field conditions, whereas two AFLPs
primer combinations with 140 polymorphic markers were recorded on a random sample of 13 genotypes per population. Ordination
and classification results based on morphophysiological data clearly kept track of the type of germplasm (i.e. landrace or
natural population) and its geographic origin, unlike results based on molecular markers. Euclidean distances among populations
based on morphophysiological traits were not correlated with Nei’s genetic distances based on molecular markers according
to Mantel’s test. Geographical distances among landrace or natural population material was correlated with distances based
on morphophysiological traits but not with those based on molecular markers. The average within-population variation estimated
via molecular markers was about 2.6-fold higher than that among populations, preventing an acceptable discrimination among
most populations. On average, natural populations tended to have within-population variation similar to varieties and somewhat
lower than landraces. Our results have implications for collection, conservation, exploitation and registration in a sui generis system of red clover genetic resources. 相似文献
443.
Childhood leukemia and fallout from the Nevada nuclear tests 总被引:1,自引:0,他引:1
Cancer mortality data from the National Center for Health Statistics, covering the period 1950 through 1978, were used to test a reported association between childhood leukemia and exposure to radioactive fallout from nuclear weapons tests in Nevada between 1951 and 1958. No pattern of temporal and geographic variation in risk supportive of the reported association was found. Comparison of these results with those presented in support of an association of risk with fallout suggests that the purported association merely reflects an anomalously low leukemia rate in southern Utah during the period 1944 to 1949. 相似文献
444.
A. da S. Pereira R. H. Coffin R. Y. Yada V. Souza Machado 《American Journal of Potato Research》1993,70(1):71-76
Progenies from crosses of ND860-2, a low reducing sugar clone, with two potato cultivars (Trent and Onaway), differing in reducing sugar content, as well as the progenies of the parents selfed, were examined for reducing sugar content. Tubers were assessed after storage at 12 C for 10 weeks (regular storage) and 4 C for 10 weeks followed by reconditioning at 20 C for two weeks (reconditioning). After regular storage, all seedling progenies had relatively high frequencies of low reducing sugar segregates (i.e., equal or less than those of ND860-2 clone). After reconditioning, a high frequency of seedlings with low reducing sugars was observed in the progeny from ND860-2/Trent (46.7%), however, they were also found in the progeny from ND860-2/Onaway (6.7%). Results of this study suggested that progenies from crosses involving ND860-2 would segregate for low reducing sugar content regardless the reducing sugar level of the other parent. 相似文献
445.
Fernanda?Salamoni?BeckerEmail author Clarissa?Damiani Adriane?Alexandre?Machado?de?Melo Paulo?Rogério?Siriano?Borges Eduardo?Valério?de Barros?Vilas Boas 《Plant foods for human nutrition (Dordrecht, Netherlands)》2014,69(4):344-350
Cookies were prepared by replacing a mixture of brown rice flour (70 %) and corn starch (30 %) (BRFCS) by buriti endocarp flour (BEF) (0, 5, 10, 15 or 20 %). BEF figured as a potential source of dietary fiber (70.53 g 100 g?1), especially of insoluble fiber (67.50 g 100 g?1), and gluten-free whole cookies showed increased dietary fiber content by adding 5, 10, 15 and 20 % BEF (8.58 to 20.02 g 100 g?1) when compared to control cookie (6.91 g 100 g?1). The addition of BEF affected diameter, spread ratio, color and texture of cookies. All cookies added with BEF were darker, harder and presented smaller diameter and smaller spread ratio than the control cookie. These difference increased proportionally to level of substitution of BRFSC by BEF. Gluten-free whole cookies with up to 15 % BEF were well accepted by consumers. Therefore, the use of BEF in cookies may increase the availability of functional ingredients source of dietary fiber for celiac consumers, add economic value to buriti processing by-products and decrease environmental impacts due to the high amounts of waste generated by buriti processing industries. 相似文献
446.
Silveira Diógenes Cecchin Basso Simone Meredith Scheffer Ebone Luciano Antônio Caverzan Andréia Machado Juliana Medianeira Schaeffer Afonso Henrique Folchini Jessica Aneris Lângaro Nadia Canali 《Journal of Crop Science and Biotechnology》2022,25(1):39-50
Journal of Crop Science and Biotechnology - The runout of newly cultivated areas in the world without recurring to the deforestation, demand a necessity to improve yield to sustain a growth... 相似文献
447.
448.
Identification of citrus hybrids through the combination of leaf apex morphology and SSR markers 总被引:5,自引:0,他引:5
Antonio Carlos de Oliveira Aristides Novac Garcia Mariângela Cristofani Marcos Antônio Machado 《Euphytica》2002,128(3):397-403
Citrus breeding programs normally face several biological obstacles such as apomixis and polyembryony that result in a cumbersome
identification of hybrid seedlings. The main purpose of this work is to describe the combined use of visual selection based
on the leaf apex morphology and SSR analysis to differentiate hybrid from nucellar seedlings derived from the cross between
the ‘Murcott’ tangor [Citrus reticulata Blanco × Citrus sinensis (L.) Osb.] and ‘Pêra’ sweet orange [Citrus sinensis(L.) Osb.]. A new morphological variable named leaf apex morphometric index is also described as the quantitative basis of
the visual selection. The efficiency of visual selection of hybrids was tested under two growth conditions, seedlings germinated
in seedbeds and in plastic tubes. Putative hybrid seedlings were also confirmed through the analysis of simple sequence repeats
(SSR). The visual selection of hybrid seedlings resulted in an increase of 87.2% (p < 0.01) and 202.2% (p <0.001) in the number of correctly identified hybrids when compared to the method of random picking of seedlings in seedbeds
and plastic tubes,respectively. The results indicate that the combination of visual selection and SSR analysis for the identification
of hybrids derived from the cross of polyembryonic citrus cultivars will improve the accuracy of the selection,save time,
and reduce the costs involved in the use of molecular markers alone in citrus breeding programs.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
449.
Ana Claudia Guerra Araujo Janine Machado Nóbrega Marisa Toniolo Pozzobon Vera Tavares de Campos Carneiro 《Euphytica》2005,144(1-2):39-50
Difficulties in obtaining new breeding lines of Brachiaria (Trin.) Griseb., an important forage grass in Brazil, are mostly related to differences in ploidy among the accessions, and
to apomixis, an asexual mode of reproduction. Usually, sexual accessions are diploid while apomicts are polyploid. Induced
tetraploids of Brachiaria brizantha (A. Rich.) Stapf have been successfully obtained and this paper presents the results of a study of their reproductive modes
and fertility. Despite frequent meiotic aberrations during microspore development, the induced tetraploids produced viable
pollen and produced progeny after controlled self-pollination. Similarly to the original diploid sexual progenitor, embryo
sacs of the Polygonum type with confirmed meiotic origin were present in the induced tetraploids suggesting chromosome doubling did not alter the
reproductive mode. The embryo sac of the Polygonum type was also observed in progenies obtained after self and open pollination. Nevertheless, embryo sacs of the Polygonum and the Panicum types within the same ovule were observed in some progenies obtained after open pollination, probably having resulted from
hybridization with tetraploid, apomictic plants. Indeed, the compatibility of the progeny with tetraploid, apomictic B. brizantha was confirmed by the formation of mature caryopses after controlled pollination. Evidence is presented that the induced tetraploids
and their progeny are sexual plants and that they are compatible with natural tetraploid B. brizantha. The induced tetraploids will be useful for analyses of apomictic inheritance as well as in the development of sexual tetraploid
lines in Brachiaria breeding programs. 相似文献
450.
Elba Ver?nica Matoso Maciel Carvalho Rosiely Félix Bezerra Ranilson de Souza Bezerra Janete Magali de Araújo Athiê Jorge Guerra Santos Maria Tereza dos Santos Correia Luana Cassandra Breitenbach Barroso Coelho 《Fisheries Science》2012,78(4):879-887
Tambaqui Colossoma macropomum is the most important Amazonian native species in South American aquaculture. Innate immunity at least partially depends on the recognition of pathogen-associated molecular patterns by receptor-recognizing pathogens (PRRs). Some PRRs have been characterized in fishes, and several studies have focused on the role of lectins in the immune system of various fishes. Lectins are proteins that specifically recognize carbohydrates and which have important biological functions. Tambaqui serum lectin (ComaSeL), which was identified on the basis of its hemagglutinating activity, was pre-purified, biochemically characterized, and used in assays of antibacterial activity against pathogenic bacteria in freshwater fishes. A study of the seasonality of this lectin was performed. Comasel activity was stable at a pH between 4.0 and 9.0 and lost 100?% of its activity at 70?°C. It recognized the carbohydrates d-galactose, 1-O-methyl-d-galactopyranoside, and d-fucose, showing antibacterial activity for Gram-negative bacteria. Its activity showed significant differences between the summer and winter (p?<?0.05, Tukey test), thereby corroborating observations that tambaqui becomes more susceptible to mortality from diseases caused by bacteria and fungi during the winter. With this information, new tools may be developed for gaining a better understanding of the role of these proteins in the immune system of the tambaqui, ultimately resulting in the improved management of this fish by pisciculturists. 相似文献