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41.
Thompson FE Midthune D Subar AF Kahle LL Schatzkin A Kipnis V 《Public health nutrition》2004,7(8):1097-1105
OBJECTIVES: We describe the methods used to develop and score a 17-item 'screener' designed to estimate intake of fruit and vegetables, percentage energy from fat and fibre. The ability of this screener and a food-frequency questionnaire (FFQ) to measure these exposures is evaluated. DESIGN: Using US national food consumption data, stepwise multiple regression was used to identify the foods to be included on the instrument; multiple regression analysis was used to develop scoring algorithms. The performance of the screener was evaluated in three different studies. Estimates of intakes measured by the screener and the FFQ were compared with true usual intake based on a measurement error model. SETTING: US adult population. SUBJECTS: For development of instrument, n=9323 adults. For testing of instrument, adult men and women in three studies completing multiple 24-hour dietary recalls, FFQ and screeners, n=484, 462 and 416, respectively. RESULTS: Median recalled intakes for examined exposures were generally estimated closely by the screener. In the various validation studies, the correlations between screener estimates and estimated true intake were 0.5-0.8. In general, the performances of the screener and the full FFQ were similar; estimates of attenuation were lower for screeners than for full FFQs. CONCLUSIONS: When coupled with appropriate reference data, the screener approach described may yield useful estimates of intake, for both surveillance and epidemiological purposes. 相似文献
42.
Caro MR Buendía AJ Ortega N Gallego MC Martínez CM Cuello F Ruiz-Ybañez MR Erb KJ Salinas J 《Veterinary research communications》2005,29(Z1):51-59
Chlamydophila abortus is the aetiological agent of enzootic abortion in small ruminants in which it infects the placenta to cause abortion during the last trimester of gestation. In a mouse model, a Th1 immune response involving IFN-gamma production and CD8+ T cells is necessary for the infection to be resolved. The authors previously demonstrated that infection with Nippostrongylus brasiliensis, a rodent gastrointestinal nematode extensively used in experimental models to induce Th2 responses, alters the specific immune response against C. abortus infection, increasing bacterial multiplication in liver and reducing specific IFN-gamma production. The aim of the present work was to clarify whether a Th2 immune response has any influence on the success of vaccination using both inactivated and attenuated vaccines. The results showed that the Th2 response established prior to vaccination did not influence the induction of protection offered by the vaccines. However, the effectiveness of this protective response can be altered, depending on the adjuvant employed in the inactivated vaccines, when the Th2 response is established after vaccination, just before challenge with C. abortus. 相似文献
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BACKGROUND: Two‐spotted spider mites (Tetranychus urticae Koch) oviposit near leaf veins or in leaf folds on the undersides of cotton (Gossypium hirsutum L.) leaves where the humid boundary layer offers protection from desiccation. The authors predicted that the boundary layer of glabrous cotton leaves should be shallower than that of hairy leaves, providing some resistance to mites. The dynamics of mite populations, leaf damage, leaf gas exchange and crop yield on two leaf hair isolines (smooth versus hairy) in two genetic backgrounds was assessed. RESULTS: Mite colonies developed faster on the hairy leaf isolines, but leaf damage per mite was higher in smooth leaf isolines, indicating more intense damage. A 50% reduction in photosynthesis on the hairy isolines required 1.8 times more mites than smooth leaves. The yield of cotton was reduced in + mite treatments, but the magnitude of reduction was similar for hairy and smooth isolines. CONCLUSION: Paradoxically, the relative inhospitality of glabrous leaves may have induced mites to concentrate in protected leaf sections, causing more localised and more severe damage, negating the yield benefits from fewer mites. These results highlight interactions between leaf microenvironment, pest behaviour and plant productivity that may have implications for other instances of plant resistance. Copyright © 2010 Society of Chemical Industry 相似文献
45.
Castillo C Benedito JL Méndez J García-Partida P Vázquez P Pereira V López-Alonso M Hernández J 《Berliner und Münchener tier?rztliche Wochenschrift》2006,119(11-12):480-485
The aim of this study was to evaluate the effects of two dietary supplements (monensin and a live yeast culture) on acid-base balance in steers maintained in a commercial feedlot system, considering effects over the growing period (14 to 23 weeks of age). A 63-day feedlot study was performed using 42 double-muscled Belgian Blue steers. Steers were allotted randomly to one of the three study groups: (1) control group [no supplementation, C], (2) monensin supplementation [MON] at a concentration of 30 mg/kg (DM basis), and (3) live Saccharomyces cerevisiae strain supplementation [SACC] at a dose of 500 mg/kg (DM basis).Venous blood samples were collected for the measurement of acid-base parameters and L-lactate. Production parameters were also used as a complementary tool for understanding the internal changes associated with supplementation. Our results show that during the study period no statistical differences were observed between supplemented and control steers, although non-supplemented animals tended to gain more efficiently than those fed monensin or yeast. Nevertheless, taking into account blood parameters, these control animals showed a greater risk of acid overload due to a more marked decline in blood buffer levels over time in comparison with supplemented steers although no differences were observed between monensin or yeast supplemented animals. Additionally, significant effect of supplementation was observed in packed cell volume (PCV) values. 相似文献
46.
Lais S. B. Dias Dayane de S. Silva Gleidson Giordano P. de Carvalho Maria Leonor G. M. L. de Araújo Fabiano F. da Silva Mara Lúcia A. Pereira Jefferson R. Gandra Victor G. O. Lima Antnio C. S. dos Santos Lucas F. de A. Bulco Vagner M. Leite Jos Esler de Freitas Júnior 《Animal Science Journal》2020,91(1)
This study aimed to investigate the effects of chitosan and whole raw soybean on nutrient intake, apparent digestibility, nitrogen utilization, microbial protein synthesis, blood metabolites, feeding behavior, ruminal fermentation, digesta kinetics, and reticular flow of nutrients of buffaloes. Four ruminally‐cannulated Murrah buffaloes (351 ± 15 kg of initial BW) were randomly assigned according to a 4 × 4 Latin square design. Treatments were arranged as 2 × 2 factorial arrangement: the first factor was whole raw soybean (WRS), and the second factor was chitosan (CHI) with or without their inclusion in diets. Intake and apparent digestibility of ether extract (p < .01; p = .04, respectively), non‐fiber carbohydrates intake (p = .03) and apparent ruminal digestibility of dry matter (p = .01) were affected by diets. An interaction effect or tendency was observed for microbial nitrogen (p = .09), concentrations, ruminal ammonia nitrogen (p = .05), total volatile fatty acid (p = .03). Association of chitosan with whole raw soybean has potential effects as a modulator of rumen fermentation; therefore, chitosan can be applied as an alternative non‐ionophore for Murrah buffaloes. 相似文献
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48.
Spain CV Scarlett JM Cully SM 《Journal of the American Animal Hospital Association》2002,38(5):482-488
Practicing veterinarians in small-animal or mixed-animal practice in New York state were surveyed about their beliefs and practices regarding the age at which dogs and cats should be neutered and their attitudes toward early neutering (at 4 months of age or younger). The majority of veterinarians routinely recommended neutering for all client animals (70.6%) and supported the routine neutering of shelter animals before adoption (90.3%). More veterinarians in this study reported at least one perceived benefit (91.3%) for early neutering than reported at least one perceived risk (84.4%). Veterinarians with experience neutering early were less likely to believe that the procedure was associated with one or more risks. 相似文献
49.
Dennis Rubbenstroth Volker Schmidt Monika Rinder Marko Legler Victor Max Corman Peter Staeheli 《Veterinary microbiology》2014,168(2-4):318-323
Avian bornaviruses (ABV) are known to be the causative agent of proventricular dilatation disease (PDD) in parrots and their relatives (Psittaciformes). A broad range of ABV genotypes has been detected not only in psittacine birds, but also in other avian species including canary birds (Serinus canaria forma domestica) and Bengalese finches (Lonchura striata f. dom.), which are both members of the order songbirds (Passeriformes).During this study 286 samples collected from captive and wild birds of various passerine species in different parts of Germany were screened for the presence of ABV. Interestingly, only three ABV-positive samples were identified by RT-PCR. They originated from one yellow-winged pytilia (Pytilia hypogrammica) and two black-rumped waxbills (Estrilda troglodytes) from a flock of captive estrildid finches in Saxony. The ABV isolates detected here were only distantly related to ABV isolates found in passerine species in Germany and Japan and form a new genotype tentatively called ABV-EF (for “estrildid finches”). 相似文献
50.