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941.
942.
Cardiorespiratory and blood gas alterations were evaluated in 6 healthy dogs that underwent a laparoscopic procedure using isoflurane anesthesia and carbon dioxide (CO(2)) pneumoperitoneum for 30 min. Heart rate, respiratory rate, body temperature, venous blood pH, partial pressure of CO(2) and oxygen, oxygen saturation, total carbon dioxide (TCO(2)) and bicarbonate were monitored. Significant alterations were hypercapnia, hypoventilation, and respiratory acidosis.  相似文献   
943.
Two experiments were conducted to assess the endogenous fraction of purine derivative (PD) excretion, urinary recovery, and intestinal digestibility of purines in Nellore heifers. For both experiments, 8 Nellore heifers fitted with ruminal and abomasal cannulas were allocated to two 4 × 4 Latin squares. The diets were based on corn silage and concentrate (60 and 40% DM basis, respectively); feces and urine samples were obtained by total collection, and abomasal DM flow was estimated using indigestible NDF as an internal marker. In Exp. I, 4 of the 8 heifers (BW 258 ± 20 kg) were also fitted with ileal cannula. The planned treatments were 4 different DMI: 1.2, 1.6, 2.0, and 2.4% of BW (DM basis). The endogenous losses and purine recovery as urinary PD were estimated using linear regression between daily urinary PD excretion (Y) and daily abomasal flow of purine bases (X), expressed in millimoles per kilogram of BW(0.75). In Exp. II, the same 8 Nellore heifers (BW of 296 ± 15 kg) were fed at 1.37% BW (DM basis). The treatments were the infusion of purines (RNA from torula yeast, type VI, Sigma) into the abomasum in increasing amounts (0, 33, 66, and 100 mmol/d). All statistical analyses were performed using the PROC MIXED procedure in SAS. In Exp. I, the DMI range was 1.16 to 1.84% of BW and did not affect (P > 0.05) the apparent RNA digestibility in the small intestine, which had a mean of 75.6%, and a true digestibility of 93.0%. The mean ratio of the N-RNA to the total-N in the ruminal bacteria was 0.137. The daily urinary PD excretion (Y, mmol/kg of BW(0.75)) was a function of RNA flow in the abomasum (X, mmol/kg of BW(0.75)): Y = 0.860X + 0.460, where 0.860 and 0.460 were the PD recovery of purines and the endogenous fraction (in mmol/kg of BW(0.75)), respectively. In Exp. II, the daily urinary PD excretion was a function of RNA flow in the abomasum: Y = 0.741X + 0.301, where 0.741 and 0.301 were the recovery of PD in urine of infused purines and the endogenous losses (in mmol/kg of BW(0.75)), respectively. In conclusion, our data suggest that in Nellore heifers the respective values of endogenous PD excretion (mmol/kg of BW(0.75)), urinary recovery of the purines absorbed in the abomasum, and true digestibility of RNA in the small intestine were 0.30, 0.80, and 0.93.  相似文献   
944.
This study demonstrated that bovine herpesvirus 5 (BoHV)-5 infected calves can develop encephalitis and remain asymptomatic. Seven calves were infected intranasally and monitored for 30 days. Cerebrospinal fluid (CSF) analysis was performed from the onset of neurological signs. Multiple sections of brain and the trigeminal ganglion were submitted to histopathology. Virus detection (PCR and isolation) was performed on CSF and tissues. Four calves developed signs of neurologic disease and died. Three calves remained asymptomatic and were euthanized 30 days post-infection. Cerebrospinal fluid mononuclear pleocytosis occurred in symptomatic and asymptomatic calves. BoHV-5 was isolated and viral DNA was detected in multiple areas of the encephalon of all calves. The viral DNA was detected in the CSF of 2 calves showing neurological signs. Histologically, inflammation was noted in the brain of all calves and confirmed that the encephalitis caused by BoHV-5 may be mild and asymptomatic.  相似文献   
945.
Anthracnose is an important disease affecting mature olive fruits, causing significant yield losses, and poor fruit and oil quality. In Portugal, high anthracnose incidence was recorded during 2003–2007 with 41% of 908 orchards surveyed displaying disease symptoms. In another 14% of the orchards, the pathogen was recorded in symptomless plants. Disease severity was on average 36%, frequently reaching 100%. In Portugal, anthracnose is endemic to neglected orchards of susceptible cultivars, but under favourable conditions it can also severely affect less susceptible cultivars. Pathogens were genetically heterogeneous, with Colletotrichum acutatum genetic group A2 as the most frequent (80%), followed by group A4 (12%) and group A5 along with C. gloeosporioides (3–4%), while groups A3 and A6 of C. acutatum were sporadic. Important geographic variations were observed in the frequencies of these populations, accompanied by year‐to‐year populational shifts. Epidemiology and histopathology studies showed the presence of the pathogens on vegetative organs year‐round, particularly on olive leaves and branches, and on weeds. These represent inoculum reservoirs where secondary conidiation occurs, and conidia are then dispersed by spring rains reaching flowers and young fruits or by autumn rains reaching pre‐mature fruits. Unripe fruits were colonized without showing symptoms up to penetration of the cuticle, but further colonization and symptom production was completed only as fruits matured. These findings challenge current control practices, particularly the timing of fungicide treatment, and contribute to improved disease management.  相似文献   
946.
Vitamin A deficiency causes xerophthalmia in preschool-aged children worldwide. The objective of this study was to estimate the genetic parameters that would be useful in selecting parent plants for developing productive hybrids with higher levels of provitamin A in the maize kernel. A complete 7 × 7 diallel mating scheme was used to generate 21 single-cross hybrids. The F1 crosses and check hybrids were evaluated in complete block design across three different Brazilian environments, and carotenoid content was analyzed by high performance liquid chromatography. General combining ability effects were significant for all traits except α-carotene This result indicates that the contribution of the additive effect was more important for provitamin A and other carotenoids and, consequently that there is high chance of improving this trait through recurrent selection methods. Line 3 produced the highest level of kernel provitamin A among the inbred lines evaluated and also demonstrated the potential to contribute to the development of genetic materials with a good performance for provitamin A. Inbred lines 1, 6, and 7 showed a higher concentration of favorable alleles for grain yield, and inbred lines 3 and 6 exhibited a higher concentration of favorable alleles for β-carotene. Hybrid 1 × 3 performed well in terms of provitamin A and grain yield and combination 2 × 3 was the best performer in terms of lutein content.  相似文献   
947.
In addition to its search for extrasolar planets, the NASA Kepler mission provides exquisite data on stellar oscillations. We report the detections of oscillations in 500 solar-type stars in the Kepler field of view, an ensemble that is large enough to allow statistical studies of intrinsic stellar properties (such as mass, radius, and age) and to test theories of stellar evolution. We find that the distribution of observed masses of these stars shows intriguing differences to predictions from models of synthetic stellar populations in the Galaxy.  相似文献   
948.
The effect of high-intensity pulsed electric fields (HIPEF) or thermal processes and refrigerated storage on water-soluble vitamins and antioxidant capacity of beverages containing fruit juices and whole (FJ-WM) or skim milk (FJ-SM) was assessed. Peroxidase (POD) and lipoxygenase (LOX) inactivation as well as color changes were also studied. High vitamin C retention was observed in HIPEF and thermally treated beverages, but a significant depletion of the vitamin during storage occurred, which was correlated with antioxidant capacity. HIPEF treatment did not affect the concentration of group B vitamins, which also remained constant over time, but thermally treated beverages showed lower riboflavin (vitamin B2) concentration. With regard to enzyme activity, thermal processing was more effective than HIPEF on POD and LOX inactivation. The color of the beverages was maintained after HIPEF processing and during storage. Consequently, HIPEF processing could be a feasible technology to attain beverages with fruit juices and milk with high vitamin content and antioxidant potential.  相似文献   
949.
The production of volatile compounds by microbial communities of cork samples taken during the cork manufacturing process was investigated. The majority of volatiles were found in samples collected at two stages: resting after the first boiling and nontreated cork disks. Volatile profiles produced by microbiota in both stages are similar. The releasable volatile compounds and 2,4,6-trichloroanisole (TCA) produced in cork-based culture medium by five isolated fungal species in pure and mixed cultures were also analyzed by gas chromatography coupled with mass spectrometry (GC-MS).The results showed that 1-octen-3-ol and esters of fatty acids (medium chain length C8-C20) were the main volatile compounds produced by either pure fungal species or their mixture. Apparently, Penicillium glabrum is the main contributor to the overall volatile composition observed in the mixed culture. The production of releasable TCA on cork cannot be attributed to any of the assayed fungal isolates.  相似文献   
950.
Bradyrhizobium strains were isolated from nodules obtained from field-grown soybean plants sampled in 12 soybean production locations in Argentina. These fields had been annually cropped with soybean and did not show decreases in yields even though they had been neither N-fertilized nor inoculated for at least the last 5 years. We hypothesized that the isolated strains maintained high competitiveness and efficiency in fixing adequate N2 levels. A set of strains that showed the highest nodular occupancy in each sampling location were assayed for symbiotic performance under greenhouse and field conditions and comparatively evaluated with Bradyrhizobium japonicum E109, the strain officially recommended for inoculant formulation in Argentina. An inoculant pool, formed by four strains obtained from nodules collected from Cañada Rica, developed higher nodular biomass than B. japonicum E 109 in assays carried out in greenhouses under well irrigated conditions. Additionally, neither nodule production nor specific nitrogenase activity decreased with respect to B. japonicum E 109 when plants were drought stressed during 7 days from sowing. The mean yields obtained under field conditions and plotted against the principal component one (CP1) obtained with an additive main effect and multiplicative interaction (AMMI) model showed that the inoculant pool from Cañada Rica had higher contribution to yield than strain E 109, although with lower environmental stability. The inoculant pool from Cañada Rica could be considered an improved inoculant and be used for preliminary assays, to formulate inoculants in Argentina.  相似文献   
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