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71.
B. Duncan X. Lascelles John B. Henry III James Brown Ian Robertson Andrea Thomson Sumrell Wendy Simpson Simon Wheeler Bernie D. Hansen Helia Zamprogno Mila Freire Anthony Pease 《Veterinary surgery : VS》2010,39(5):535-544
Objective: To determine the prevalence of radiographic signs of degenerative joint disease (DJD) in a randomly selected sample of domestic cats. Study Design: Prospective observational study. Animals: Client‐owned cats. Methods: Cats (n=100) from a single practice and equally distributed across 4 age groups (0–5; 5–10; 10–15, and 15–20 years old) were randomly selected (regardless of heath status) and sedated for orthogonal radiographic projections of all joints and the spine. Quasi‐Poisson regression analysis was used to investigate the relationship between patient demographics, blood biochemistry, hematologic and urine analysis variables, and DJD severity. Results: Most (92%) cats had radiographic evidence of DJD; 91% had at least 1 site of appendicular DJD and 55% had ≥1 site of axial column DJD. Affected joints in descending order of frequency were hip, stifle, tarsus, and elbow. The thoracic segment of the spine was more frequently affected than the lumbosacral segment. Although many variables were significantly associated with DJD, when variables were combined, only the association between age and DJD was significant (P<.0001). For each 1‐year increase in cat age, the expected total DJD score increases by an estimated 13.6% (95% confidence interval: 10.6%, 16.8%). Conclusion: Radiographically visible DJD is very common in domesticated cats, even in young animals and is strongly associated with age. Clinical Relevance: DJD is a common disease of domesticated cats that requires further investigation of its associated clinical signs. 相似文献
72.
Francisco A Macías Francisco JR Mejías Jos MG Molinillo 《Pest management science》2019,75(9):2413-2436
Allelopathy is the biological phenomenon of chemical interactions between living organisms in the ecosystem, and must be taken into account in addressing pest and weed problems in future sustainable agriculture. Allelopathy is a multidisciplinary science, but in some cases, aspects of its chemistry are overlooked, despite the need for a deep knowledge of the chemical structural characteristics of allelochemicals to facilitate the design of new herbicides. This review is focused on the most important advances in allelopathy, paying particular attention to the design and development of phenolic compounds, terpenoids and alkaloids as herbicides. The isolation of allelochemicals is mainly addressed, but other aspects such as the analysis and activities of derivatives or analogs are also covered. Furthermore, the use of allelopathy in the fight against parasitic plants is included. The past 12 years have been a prolific period for publications on allelopathy. This critical review discusses future research areas in this field and the state of the art is analyzed from the chemist's perspective. © 2019 Society of Chemical Industry 相似文献
73.
G. Vázquez J. González-Alvarez J. Santos M.S. Freire G. Antorrena 《Industrial Crops and Products》2009,29(2-3):364-370
The potential of chestnut shell and eucalyptus bark extracts as phenol substitutes in the formulation of adhesives, as chrome substitutes in leather tanning and as a source of antioxidants compounds has been studied. The influence of extraction conditions, type and concentration of alkaline compounds (NaOH, Na2SO3 and Na2CO3) and temperature, on extraction yield and on extract characteristics: Stiasny number, tannin content, total phenols content, FRAP (ferric reducing/antioxidant power) antioxidant capacity and molecular weight distribution was analysed. Chestnut shell extracts had much better properties than eucalyptus bark extracts and significantly higher extraction yields were obtained. The increase of temperature from 70 to 90 °C not only increased the extraction yield but also improved the quality of the extracts. For both materials, the 2.5% Na2SO3–90 °C extract, together with the 2.5% NaOH–2.5% Na2SO3–90 °C extract for chestnut shell, showed high extraction yields and the best properties for all the applications proposed. 相似文献
74.
M.C. Marinho M.A. Pinho R.D. Mascarenhas F.C. Silva M.M. Lordelo L.F. Cunha J.P.B. Freire 《Livestock Science》2007,108(1-3):240-243
Forty eight 21 days old piglets were used to compare the effect of prebiotic or probiotic supplementation and ileo rectal anastomosis on the morphology of the small intestine. Half of the piglets were maintained intact and the other half was subjected to an ileo rectal anastomosis (IRA). Each group of piglets received one of the following diets: 1) basal diet (C), 2) basal diet supplemented with a Xylo-oligosaccharide (XOS), 3) basal diet supplemented with a Saccharomyces cerevisiae (SC) and 4) basal diet supplemented with XOS and SC. Villus height was greatest with XOS and with XOS + SC, only in the ileum, as compared to controls. In the duodenum, crypt width was highest in the control group, but no significant differences were found in the jejunum and ileum. The IRA piglets had longer villi in the jejunum and shorter villi in the ileum. The crypt depth was greater in the duodenum and in the ileum of IRA piglets. Villus height/crypt depth was lower in the duodenum and in the ileum, in the IRA piglets. In conclusion, the XOS, but not the SC, moderately modified the intestinal morphology. The IRA modified the intestinal villus and crypt architecture but its consequence on the absorption of nutrients needs to be investigated. 相似文献
75.
V.M.R. Pires C.M.A. Fontes L.M.A. Ferreira C.I.P.D. Guerreiro L.F. Cunha J.P.B. Freire 《Livestock Science》2007,109(1-3):57-59
A trial involving 24 weaned piglets was conducted to evaluate the effect of two alpha-galactosidases, associated or not with a cellulase and hemicellulase enzyme mixtures, for improving the nutritive value of a cereal–Lupinus albus based diet. Enzyme supplementation was unable to improve apparent ileal digestibility of crude protein and true ileal digestibility of amino acids. However, ileal digestibility of NDF tended to increase with enzyme supplementation, suggesting a residual hemicellulase activity in both -galactosidases mixtures under analysis. 相似文献
76.
This study was carried out to assess the in vitro quality of canine semen frozen in an ultrafreezer at -152 degrees C and to evaluate the male-to-male variation of frozen semen in five male dogs of the Canarian Mastiff breed. Four ejaculates of each dog were processed individually (5% glycerol and 0.5% Equex) to reach a final concentration of 100 x 10(6) spermatozoa/ml. Then, two freezing techniques were tested to assess the seminal quality (sperm motility, live spermatozoa and abnormal sperm cell percentages) at 1, 30, 60, 120 and 360 days after freezing: (i) semen was frozen and stored in liquid nitrogen; (ii) semen was frozen and stored in the ultrafreezer at -152 degrees C. After freezing-thawing, both freezing protocols showed no significant differences in sperm motility and the percentages of live and abnormal spermatozoa. On the other hand, the microscopic characteristics of spermatozoa in fresh semen were practically similar among males; however, after the semen processing and freezing, significant differences were observed (p < 0.05) among males, especially as regards sperm motility. This inter-individual variability was detected in both freezing protocols, showing that the male-to-male variation in the seminal quality post-freezing was independent of the freezing technique used. The in vitro results obtained in the Canarian Mastiff breed confirmed that the use of ultra-freezers at -152 degrees C is a potential alternative to liquid nitrogen for storing canine semen for long periods of time. 相似文献
77.
In this study we have examined luteal function in non-lactating and late lactation dairy cows on day 5 of the cycle, during the period of the post-ovulatory progesterone rise. Comparison of luteal progesterone content and in vitro synthetic capacity with circulating plasma progesterone demonstrated that circulating progesterone concentration is a function of total luteal activity rather than the activity of individual units of tissue. Incubation of luteal tissue in vitro demonstrated stimulatory activity of LH and IGF-I, and to a greater degree IGF-II, on luteal progesterone synthesis. Finally the study showed no effect of double ovulation on luteal function. Occurrence of double ovulation in 35% of animals was not associated with any difference in luteal function or plasma progesterone concentrations. 相似文献
78.
79.
Mary Alexandra da Costa Fernanda Pinto‐Ferreira Roblia Pond Amorim de Almeida Felippe Danyel Cardoso Martins Adriene Lino Pires Marcelle Mareze Regina Mitsuka‐Bregan Roberta Lemos Freire Rosalynd Vinicios da Rocha Moreira Juliene Meira Borges Italmar Teodorico Navarro 《Zoonoses and public health》2020,67(2):122-129
80.
With the use of scanning tunneling microscopy, it is shown that germanium atoms adsorbed on the (100) surface of silicon near room temperature form chainlike structures that are tilted from the substrate dimer bond direction and that consist of two-atom units arranged in adjoining substrate troughs. These units are distinctly different from surface dimers. They may provide the link missing in our understanding of the elementary processes in epitaxial film growth: the step between monomer adsorption and the initial formation of two-dimensional growth islands. 相似文献