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91.
Anesthetic respiratory effects of sevoflurane (SEVO) were compared with isoflurane (ISO) in unpremedicated dogs. Minimum alveolar concentration (MAC), apneic concentration (AC), and anesthetic index (AI) of SEVO and ISO were determined in eight 1‐year‐old healthy dogs, weighing 19 ± 3 kg (mean ± SEM) in a randomized complete block multiple cross‐over design. Dogs were mask‐induced with either SEVO or ISO in 100% oxygen. Following endotracheal intubation, dogs were instrumented, mechanically ventilated, and MAC was determined using a tail‐clamp method. Next, spontaneous ventilation was re‐established, and anesthetic concentration was increased to determine the AC. Throughout the anesthetic event, heart rate (HR), systolic blood pressure (SAP), mean blood pressure (MAP), diastolic blood pressure (DAP), respiratory rate (RR), end‐tidal carbon dioxide (Pe ′CO2), and oxyhemoglobin saturation (SpO2) were recorded at 3‐minute intervals. Following AC determination, AI was calculated as AC/MAC, and dogs were allowed to recover. Each dog was anesthetized four times (twice with ISO and SEVO each) at 1‐week intervals. All data were analyzed using the two‐way anova . Multiple comparisons were performed between ISO and SEVO treatments. Statistical significance was set at p < 0.05. Significant differences were noted between agents for MAC (SEVO, 2.13 ± 0.10%; ISO, 1.38 ± 0.14%; p < 0.0001), AC (SEVO, 7.34 ± 0.13%; ISO, 3.60 ± 0.13%; p < 0.0001), and AI (SEVO, 3.46 ± 0.22; ISO, 2.63 ± 0.14; p = 0.0002). Physiologic parameters were compared between SEVO and ISO at 1MAC, 2MAC, 3MAC, and AC. No differences were noted between SEVO and ISO treatments for cardiovascular parameters (HR, SAP, MAP, DAP). Significant differences were noted, favoring SEVO, for all respiratory parameters (RR, Pe ′CO2, SpO2) at increasing MAC multiples. Additionally, regression analysis was conducted for physiologic variable data points. Analysis of Pe ′CO2 data points demonstrated a significant slope difference of ?6.47 ± 1.02 (BSEVO ? BISO; p < 0.0001; r2 = 0.6042) favoring SEVO. While expected dose‐related ventilatory depression was noted for both agents, all the respiratory parameters for SEVO demonstrated less respiratory depression than ISO at equipotent doses. These results indicated that SEVO caused less dose‐dependent ventilatory depression than ISO, having a significantly higher AI and causing less detrimental change in pulmonary parameters at increasing levels of MAC.  相似文献   
92.
Epidemiological studies have linked whole grain consumption to prevention of several chronic diseases. Whole grain is a source of important phytochemicals, such as ferulic acid (FA). FA is the most abundant phenolic and major contributor to the in vitro antioxidant capacity of wheat grain. Several studies have reported highly variable results on FA bioavailability (0.4–98%). The binding of FA to polysaccharides may limit its bioavailability. Therefore, our study aimed at monitoring release features of FA during gastrointestinal (GI) transit. This was termed bioaccessibility. The bioaccessibility of FA was studied from different wheat fractions and breads with the use of a dynamic in vitro system that simulates the upper GI transit and digestion. The results showed low bioaccessibility of FA from the wheat fractions and breads (<1%). However, the bioaccessibility was high when free FA was added to flour (∼60%). The bioaccessibility of FA appeared to be determined by the percentage of free FA. In wheat grain, most of FA is bound to arabinoxylans and other indigestible polysaccharides restricting its release in the small intestine. New processing developments should be considered to increase free FA in the cereal matrix in order to improve its bioavailability and systemic health effect.  相似文献   
93.
94.
SUMMARY: Immunity in 12 weaner Merino sheep fed a low selenium (Se) diet (low Se sheep) was compared with that in 10 matching sheep fed the same diet but each given an intraruminal Se pellet (high Se sheep), while the sheep were housed in individual, sheltered pens. All sheep were challenged with killed Brucella abortus cells (days 0 and 28), rabbit red blood cells (days 0, 7 and 28) and corynebaclerium pseudotuberculosis toxoid (days 0 and 28), and serum antibody titres were measured weekly for 8 weeks from day 0. The sheep were then experimentally infected with Haemonchus conforfus, and slaughtered 8 weeks later. The mean antibody titre to B. abortus, measured by 4 different tests, was significantly higher in the high Se sheep on occasions during the primary immune response phase (Rose Bengal test - day 21 (p < 0.05), day 28 (p < 0.025); complement fixation - day 7 (p < 0.05); enzyme-llnked immunosorbent assay - day 14 (p < 0.01); serum agglutination - no differences), but not during the secondary phase. The mean antibody titre to rabbit red blood cells, measured by haemagglutination test, was marginally higher in the high Se sheep on day 49 (p = 0.049). The mean antibody titre to C. pseudotuberculois, measured by enzyme-linked immunosorbent assay, was not significantly different between the groups at any time during the trial. In addition, the mean invitro responsiveness of peripheral blood lymphocytes to stimulation with phytohaemagglutinin in the high Se sheep was significantly greater than that in 10 sheep from the low Se group on day 22 (p < 0.01), but not day 50. However, there were no significant differences in the mean number of sheep in which the infection with H. contortus established, time to first shedding of eggs in faeces, abomasal worm burdens at necropsy, or inflammatory response in the abomasal mucosa in the sheep in each group. The results showed that the low Se sheep produced strong overall immune responses that were largely comparable to those in the high Se sheep.  相似文献   
95.
Bovine herpesvirus 5 antigens were detected by indirect immunofluorescence in the cytoplasm of tumor cells derived from bovine ocular squamous cell carcinomas. The number of tumor cells expressing bovine herpesvirus 5 antigens was increased following exposure to ultraviolet light or maintenance in pH 8.4 media. Infectious virus could not be detected in homogenates of tumors or by explantation of tumors. However, medium removed from the ocular tumor explants induced cytoplasmic vacuolization, inclusions and syncytia when inoculated onto bovine fetal spleen monolayers. Acridine orange staining revealed these cytoplasmic inclusions to contain double-stranded deoxyribonucleic acid. These results provide evidence that bovine herpesvirus 5 may be associated with bovine ocular squamous cell carcinoma.  相似文献   
96.
97.
A study was conducted to evaluate the performance of a nucleic acid sequence-based amplification (NASBA) assay for the detection of foot-and-mouth disease virus (FMDV). Two detection methods: NASBA-electrochemiluminescence (NASBA-ECL) and a newly developed NASBA-enzyme-linked oligonucleotide capture (NASBA-EOC) were evaluated. The diagnostic sensitivity of these assays was compared with other laboratory-based methods using 200 clinical samples collected from different regions of the world. Assay specificity was also assessed using samples (n=43) of other viruses that cause vesicular disease in livestock and genetic relatives of FMDV. Concordant results were generated for 174/200 (87.0%) of suspect FMD samples between NASBA-ECL and real-time RT-PCR. In comparison with the virus isolation (VI) data, the sensitivity of the NASBA-ECL assay was 92.9%, which was almost identical to that of the real-time RT-PCR (92.4%) for the same set of samples. There was broad agreement between the results of the NASBA-ECL and the simpler NASBA-EOC detection method for 97.1% of samples. In conclusion, this study provides further data to support the use of NASBA as a rapid and sensitive diagnostic method for the detection and surveillance of FMDV.  相似文献   
98.
Subperiosteal hematomas are accumulations of blood between a bone and the periosteum leading to elevation of the periosteum. When ossified they have a mineralized outer rim. For this retrospective, multi‐institutional case series, medical records were searched to identify dogs that underwent CT for focal calvarial swellings noted acutely after trauma. A total of four dogs were included. Computed tomography images were reviewed for each case. The focal swellings had progressed in size during the weeks after the head trauma until the time of imaging. Findings in all cases included a fluid to soft tissue attenuating mass‐like lesion with smoothly marginated peripheral mineralization. Diagnosis was confirmed in two cases by cytology and/or histopathology. Therefore, authors recommend that subperiosteal hematoma be included in the differential diagnosis list for dogs with these clinical and CT characteristics. Based on our review of the literature, this is the first report to describe the CT features of calvarial subperiosteal hematomas in dogs.  相似文献   
99.
Interference between two freely expanding Bose-Einstein condensates has been observed. Two condensates separated by approximately 40 micrometers were created by evaporatively cooling sodium atoms in a double-well potential formed by magnetic and optical forces. High-contrast matter-wave interference fringes with a period of approximately 15 micrometers were observed after switching off the potential and letting the condensates expand for 40 milliseconds and overlap. This demonstrates that Bose condensed atoms are "laser-like"; that is, they are coherent and show long-range correlations. These results have direct implications for the atom laser and the Josephson effect for atoms.  相似文献   
100.
Genetic Diversity Based on AIIozyme Alleles of Chinese Cultivated Rice   总被引:1,自引:0,他引:1  
Genetic diversity was analyzed with 6 632 core rice cultivars selected from 60 282 Chinese rice accessions on the basis of 12 allozyme loci, Pgil, Pgi2, Amp1, Amp2, Amp3, Amp4, Sdhl, Adhl, Estl, Est2, Est5 and Est9, by starch gel electrophoresis. Among the materials examined, 52 alleles at 12 polymorphic loci were identified, which occupied 96.3% of 54 alleles found in cultivated germplasm of O. sativa L. The number of alleles per locus ranged from 2 to 7 with an average of 4.33. The gene diversity (He) each locus varied considerably from 0.017 for Amp4 to 0.583 for Est2 with an average gene diversity (Ht) 0.271, mid Shannon-Wiener index from 0.055 to 0.946 with an average of 0.468. The degree of polymorphism (DP) was in a range from 0.9 to 46.9% with an average of 21.4%. It was found that the genetic diversity in japonica (Keng) subspecies was lower in terms of allele's number, Ht and S-W index, being 91.8, 66.2 and 75.7% of indica (Hsien) one, respectively. Significant genetic differentiation between indica and japonica rice has been appeared in the loci Pgil, Amp2, Pgi2, and Est2, with higher average coefficient of genetic differentiation (Gst) 0.635, 0.626, 0.322 and 0.282, respectively. Except less allele number per locus (3.33) for modern cultivars, being 76.9% of landraces, the Ht and S-W index showed in similar between the modem cultivars and the landraces detected. In terms of allozyme, the rice cultivars in the Southwest Plateau and Central China have richer genetic diversity. The present study reveals again that Chinese cultivated rice germplasm has rich genetic diversity, showed by the allozyme allele variation.  相似文献   
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