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41.
It is well known that heart rate or arterial blood pressure may increase in response to surgical stimulation despite the absence of a purposeful movement. However, there is limited information regarding anesthetic requirement for blunting adrenergic response in dogs. This study was designed to compare the minimum alveolar concentrations of sevoflurane required to prevent autonomic response (MAC-BAR) and purposeful movement (MAC) in dogs. Sevoflurane MAC-BAR and MAC were determined in 5 beagle dogs by judging dogs' response to a noxious electrical stimulus applied to the gingiva. The sevoflurane MAC-BAR was significantly higher than MAC (3.33 ± 0.48 vs 2.10 ± 0.28%, P=0.005). These results suggested that autonomic responses occurred at sevoflurane anesthetic concentrations at which purposeful movements were absent.  相似文献   
42.
This study was conducted to show that dietary supplementation of a fungus, Aspergillus awamori called Koji in Japan, reduces skeletal muscle protein breakdown and stimulates growth in broiler chickens. A total of 30 chicks at 15 days of age was divided into control and two treatment groups (10 birds per treatment). Control group was fed basal diet and treatment groups were fed the basal diets supplemented with A. awamori at levels of 0.05% and 0.2%. The birds were raised for 12 days from 15 to 27 days of age and then the effect on growth, organ weights and plasma 3‐methylhistidine concentration and digestibilities of protein and energy was evaluated. The messenger RNAs (mRNAs) of atrogin‐1, ubiquitin, proteasome, m‐calpain, µ‐calpain, β‐actin, myosin and pax‐7 in the breast muscle were also measured. Body weight gain and breast muscle weight were increased, although feed intake was decreased by the fungus and thus feed efficiency was increased. Protein and energy digestibilities were increased. Furthermore, plasma 3‐methylhistidine concentration was decreased by the fungus. The mRNAs of atrogin‐1, ubiquitin, proteasome, m‐calpain and µ‐calpain were all decreased. The mRNA of β‐actin but not myosin and pax‐7 was slightly increased by the fungus. In conclusion, feeding A. awamori improves growth performance because skeletal muscle proteolytic activity is reduced and digestibilities of energy and protein are increased.  相似文献   
43.
To clarify the effect of nutritive conditions on changes in immune cells in Japanese Black (JB) calves during the growth period, leukocyte populations were analyzed in ten healthy JB calves managed in one herd. The calves were divided into two groups: five calves in Group 1 were given insufficient nutrition, and the other five calves in Group 2 received adequate nutrition. The levels of serum total cholesterol and glucose were significantly lower in Group 1 than in Group 2 at 1 month. The numbers of CD3+, CD4+ and CD8+ cells tended to be lower in Group 1 than in Group 2 at months 1 and 2, and the difference in CD4+ was significant at month 2. The number of MHC class-II(+high) cells was significantly lower in Group 1 than in Group 2 at months 1 and 2. These results suggest that adequate nutrition might stimulate an increase in immune cells in calves during the growth period.  相似文献   
44.
The effects of porcine sarcoplasmic proteins (SP) on the physicochemical properties of meat emulsion gel were examined. Meat emulsion was prepared from water‐washed pork meat (WWM), corn oil and SP. Whole SP (W‐SP) enhanced the breaking stress of the WWM emulsion gel as well as other animal proteins in the presence of 0.2 mol/L NaCl. The breaking stress of the emulsion with W‐SP increased with an increase in corn oil content. Furthermore, this tendency was more noticeable at a lower NaCl concentration (0.15 mol/L) rather than at 0.45 mol/L NaCl. Ammonium sulfate (AS) treatment fractionated W‐SP into three portions (SP‐f1, SP‐f2 and SP‐f3), which were the precipitates at 0–50% and 50–75% AS saturation and the supernatant at 75% AS saturation, respectively. The fractions SP‐f2 and SP‐f3 increased the gel strength more than W‐SP. In particular, the fraction SP‐f3 increased the gel strength approximately 10‐fold compared to the control. Sodium dodecyl sulfate‐polyacrylamide gel electrophoresis analysis showed that SP‐f3 had several kinds of proteins and a main protein with a molecular mass of 35 kDa, which corresponded to glyceraldehyde 3‐phosphate dehydrogenase. These results indicate that the influence of SP should not be ignored when processing of low‐salt meat products and the fraction SP‐f3 has a gel‐enhancing factor for myofibrillar proteins.  相似文献   
45.
46.
Regions of strong coupling between soil moisture and precipitation   总被引:26,自引:0,他引:26  
Previous estimates of land-atmosphere interaction (the impact of soil moisture on precipitation) have been limited by a lack of observational data and by the model dependence of computational estimates. To counter the second limitation, a dozen climate-modeling groups have recently performed the same highly controlled numerical experiment as part of a coordinated comparison project. This allows a multimodel estimation of the regions on Earth where precipitation is affected by soil moisture anomalies during Northern Hemisphere summer. Potential benefits of this estimation may include improved seasonal rainfall forecasts.  相似文献   
47.
The objective of this review is to make current knowledge on the nitrogen (N) load throughout the atmosphere (airborne N load) available to readers, with special emphasis on Japanese and Chinese agroecosystems. Key species of airborne N are ammonia, nitrogen dioxide, nitrogen oxide, nitric acid, nitrous acid and particulate ammonium and nitrate. Organic N also exists in the atmosphere. The main processes in terms of the airborne N load involve emission, atmospheric transportation and transformation, atmospheric deposition and environmental impacts. Agricultural activities are the largest emitters of ammonia through emissions mainly from livestock waste and field-applied N fertilizers. The ammonia emissions in China in 1995 from chemical fertilizers and organic fertilizers, such as animal excreta, were estimated to be 3.56 and 2.04 Tg N year−1, respectively, and the emissions in Japan were 0.059 and 0.069 Tg N year−1, respectively. The most fundamental causes of the airborne N load in relation to Japanese and Chinese agriculture were intensive livestock farming in Japan and over use of N fertilizers in China. However, agroecosystems are also a sink for airborne N. Atmospheric N deposition was up to 20 and 60 kg N ha−1 year−1 in Japan and China, respectively. The unrelenting load of airborne N continues in Japan and China. The development of a simple, but accurate method to determine the dry deposition flux that is applicable to simultaneous and multipoint observations would be valuable. The establishment of cross relationships among in situ observations, remote sensing and numerical modeling is also needed to cope with the issue by assessing the actual status, predicting the future status and working out effective measures.  相似文献   
48.
The present study aimed to elucidate ammonia (NH3) volatilization loss following surface incorporation (0–15 cm mixing depth) of nitrogen (N) fertilizer in an upland field of light-colored Andosol in central Japan. A dynamic chamber technique was used to measure the NH3 effluxes. Poultry manure, pelleted poultry manure, cattle manure, pelleted cattle manure and ammonium sulfate were used as N fertilizers for basal fertilization to a bare soil with surface incorporation. All three experiments in summer and autumn 2007 and in summer 2008 showed negligible NH3 volatilization losses following the application of all N fertilizers with the same application rate of 120 kg N ha−1 as total N; these negligible losses were primarily ascribed to chemical properties of the soil, that is, its high cation exchange capacity (283 mmolc kg−1 dry soil) and relatively low pH(H2O) (5.9). In addition, the surface incorporation, the very small ratio of ammoniacal N to total N for the manure, and the decrease in soil pH to ≤5.5 following applications of ammonium sulfate were also advantageous to the inhibition of NH3 volatilization loss from the field-applied N fertilizers.  相似文献   
49.
ABSTRACT:   One of the biggest and long-standing difficulties in investigation of larval ecology in the field is species-level identification. In the present study, we developed polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) analysis based on the large subunit (LSU) rRNA gene (rDNA) D1/D2/D3 region for identification of multiple species of bivalve larvae using 14 species of bivalve collected from Maizuru Bay. The LSU rDNA D1/D2/D3 region of all analyzed species could be amplified by PCR using bvD1f/bvD3r primers, and RFLP analysis by Hae III digestion on the PCR products showed species-specific fragment patterns. Furthermore, this analysis applied to single bivalve larvae in Maizuru Bay revealed efficient amplification of the target region and the species-specific pattern from 80% of the larvae, 75% of which showed a pattern that matched a certain pattern of the adult bivalves. In addition, the analysis of inter- and intraspecies variation of the LSU rDNA D1/D2/D3 region using the sequence data of the genus Crassostrea from the DDBJ database showed high applicability of this RFLP analysis on closely related species. Because of the wide applicability and technical simplicity, this method can become the standard for the identification of bivalve larvae species once the sequence data of the LSU rDNA D1/D2/D3 region of many bivalve species have been accumulated.  相似文献   
50.
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