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71.
A total of 22 radiographic studies was made to determine comparative gastric emptying times of two different solid test meals (intact kibble food and ground kibble food mixed with barium sulfate suspension) in four mature (15-26 months) normal Beagle dogs under controlled conditions. Complete gastric emptying times of the intact kibble and ground kibble meals of a given dose (8 g/kg of dog food plus 5-7 ml/kg of the contrast agent) ranged from five to ten hours (7.6 ± 1.98 hours with intact kibble meal and 7.0 ± 1.86 hours with ground kibble meal). Feeding a halfdose of ground kibble meal (4 g/kg of dog food plus 3.5 ml/kg of the contrast agent) resulted in complete gastric emptying times of four to six hours (4.7 ± 0.67 hours). Individual dogs had repeatable gastric emptying times although the times varied among different dogs.  相似文献   
72.
This report compares results from imaging of transitional cell carcinoma of the urinary bladder in 15 dogs using intravenous urography, double-contrast cystography, and ultrasonography. Intravenous urography demonstrated filling defects in the urinary bladder in 3 of the 5 cases examined with this modality. Double-contrast cystography identified bladder masses in 8 of 10 animals. Ultrasonography was the only imaging modality which detected bladder masses in all patients.  相似文献   
73.
Radiographically, the liver may appear normal even if severely diseased. Ultrasonography can be an important adjunct in the evaluation of diffuse parenchymal hepatic disease. Diffuse liver disease appears ultrasonographically as a change in liver echogenicity from normal when compared with the renal cortex or spleen. Diffuse liver disease can be characterized as either hyperechoic due to fatty change, steroid hepatopathy, and cirrhosis or hypoechoic due to congestion, suppurative hepatitis, and lymphoma. Ultrasonographic diagnosis of diffuse liver disease should be substantiated by biopsy and histopathologic evaluation.  相似文献   
74.
A novel angiotensin‐converting enzyme (ACE) inhibitory peptide was isolated and purified from chicken bone extract by enzymatic digestion. The peptide was defined as an ACE inhibitor, and it demonstrated antihypertensive activity following oral administration to spontaneously hypertensive rats (SHRs). The results of this study suggest that peptides derived from an extract of chicken bones, administered orally, have the ability to reduce the blood pressure of SHRs significantly over a short period of time (3 h). Moreover, the blood pressure then remains low for 3 h. This peptide derived from chicken bones may therefore have great value as a short‐term remedy for chronic conditions such as high blood pressure. The amino acid sequence of the peptide was YYRA (Tyr‐Tyr‐Arg‐Ala), which was the origin of the Ig heavy chain V region (27–30 position). The IC50 value of its synthetic peptide was 33.9 μg/mL. We suggest that the ACE inhibitory and antihypertensive peptides derived from chicken bone extract may contribute to develop physiologically functional foods or improve food functionality.  相似文献   
75.
Root/shoot(R/S)ratio is an important index for assessing plant health,and has received increased attention in the last decades as a sensitive indicator of plant stress induced by chemical or physical agents.The R/S ratio has been discussed in the context of ecological theory and its potential importance in ecological succession,where species follow different strategies for above-ground growth for light or below-ground competition for water and nutrients.We present evidence showing the R/S ratio follows a biphasic dose–response relationship under stress,typical of hormesis.The R/S ratio in response to stress has been widely compared among species and ecological succession classes.It is constrained by a variety of factors such as ontogeny.Furthermore,the current literature lacks dose-response studies incorporating the full dose–response continuum,hence limiting scientific understanding and possible valuable application.The data presented provide an important perspective for new-generation studies that can advance current ecological understanding and improve carbon storage estimates by R/S ratio considerations.Hormetic response of the R/S ratio can have an important role in forestry for producing seedlings with desired characteristics to achieve maximum health/productivity and resilience under plantation conditions.  相似文献   
76.
The purposes of this research were to use fig protease for texture tenderizing, and to inhibit angiotensin I‐converting enzyme (ACE) action and γ‐aminobutyric acid (GABA) formation of meat. Liberated peptides by the enzymatic action of fig protease in processing meat and free amino acids were determined and ACE inhibitory activity was assayed. Meat treated with fig protease became tender as indicated by shear force value (SFV) which was half of those of non‐fig treated meat during storage even at 5°C. Liberated peptides, free amino acids and GABA increased while extremely low levels of Glu were detected after storage. The optimal temperature of fig protease against meat was 80°C. However, the activity of fig protease decreased after pre‐heating more than 40°C. High ACE inhibitory activity of a mixture of fig and meat was found around 80°C, and the value corresponded to the amount of liberated peptide. A lot of liberated peptides were found at 60–80°C and pasterization of meat product becomes convenient to produce peptides. Production of ACE inhibitory peptides and GABA can be expected as the healthy functional meat product such as antihypertensive activity and improve brain function.  相似文献   
77.
High-level cutting without stubble shaving has been recommended in the cultivation of forage sugarcane, KRFo93-1. However, it is unclear whether this management practice is appropriate for the more recently developed variety Shimanoushie. Therefore, the aim of this study was to compare the dry matter yield of both varieties to high-level cutting. The study included five ratoon crops (RC1–RC5). In KRFo93-1, dry matter yield was higher in HC plots (high-level cutting without stubble shaving plots) than in Control plots (stubble shaving after high-level cutting plots), and the differences were significant for the first three ratoon crops. A similar trend was observed in Shimanoushie; however, the dry matter yield of HC plots was slightly lower than Control plots in RC4 and RC5 owing to a lower stem number. Although the sum of dry matter yield of five ratoon crops was significantly higher in HC plots of both varieties, the influence of high-level cutting was more effective in KRFo93-1 than in Shimanoushie.  相似文献   
78.
The interaction of drought and elevated carbon dioxide concentration ([CO(2)]) on carboxylation capacity of Rubisco (V(cmax)) and susceptibility to photoinhibition may be an important determinant of plant responses to seasonal fluctuations in precipitation in an anticipated elevated [CO(2)] environment. Japanese white birch (Betula platyphylla var. japonica) leaves that developed wholly during a period of drought showed an increase in leaf nitrogen and a decrease in leaf carbohydrates that could ameliorate photosynthetic down-regulation, defined as a decrease in V(cmax) in response to elevated [CO(2)]. Photochemical quenching (q(P)) was decreased by elevated [CO(2)] but increased by drought when compared at a given intercellular [CO(2)] (C(i)), indicating that elevated [CO(2)] could increase the risk of photoinhibition, whereas long-term drought could alleviate the risk of photoinhibition. However, only a small variation in q(P) was measured among seedlings in the various water availability x [CO(2)] treatment combinations, consistent with the small treatment differences in chronic photoinhibition among the seedlings, as indicated by the ratio of variable to maximum chlorophyll fluorescence after overnight dark-adaptation. Our results suggest that the offsetting responses-reduced V(cmax) plus increased C(i) at elevated [CO(2)] and increased V(cmax) plus reduced C(i) under drought conditions-resulted in a narrow range of susceptibility to photoinhibition at the growth [CO(2)] in Japanese white birch seedlings grown in various water availability x [CO(2)] treatment combinations.  相似文献   
79.
We compared shoot and needle morphology and photosynthesis in Picea glehnii (Friedr. Schmidt) M.T. Mast. and Picea jezoensis (Sieb. et Zucc.) Carr. trees planted on immature volcanic ash and well-developed brown forest soils to investigate whether species differences in morphological and physiological plasticity affected tree growth on different soil types. Height growth of P. glehnii was reduced by about 10% on volcanic ash compared with forest soil, whereas that of P. jezoensis was reduced by more than 60%. Needle morphology of P. glehnii was unaffected by soil type. In contrast, needles of P. jezoensis trees growing on volcanic ash were shorter, narrower and thicker, with less dry mass and area, than those of trees growing on forest soil, and specific needle area was lower, indicating lower foliar light-interception efficiency. In both species, changes in needle morphology with increasing irradiance were similar in trees growing on both soil types, indicating that plasticity of needle morphology was unaffected by soil type. In both species, shoot mass and shoot silhouette area were lower and needle mass per unit shoot mass was higher in trees growing on volcanic ash than in trees growing on forest soil. Trees of both species had more needles per unit shoot length, lower shoot silhouette to projected needle area ratios and lower shoot silhouette areas per unit shoot mass (SAM) on volcanic ash than on forest soil, indicating lower shoot-level light-interception efficiency. For P. glehnii, the response of shoot morphology to increasing irradiance was similar on both soil types, with the exception of SAM, which showed lower plasticity in trees growing on volcanic ash. In contrast, shoot-level morphological plasticity of P. jezoensis was reduced in trees growing on volcanic ash. Light-saturated maximum photosynthetic rate (P(max)) of P. glehnii was unaffected by soil type, whereas mass-based P(max) of P. jezoensis was lower in trees growing on volcanic ash than in trees growing on forest soil. In P. jezoensis trees growing on forest soil, area-based P(max) increased with increasing irradiance, but this response was not observed in trees growing on volcanic ash. As a result, area-based P(max) at the top of the canopy was 39 to 54% lower in trees growing on volcanic ash than in trees growing on forest soil. Our results indicate that constraints on morphological acclimation to high irradiances may contribute to reduced height growth of P. jezoensis on volcanic ash.  相似文献   
80.
This study examined the usage of a dry shipper for cryopreservation of Epinephelus septemfasciatus (Thunberg) spermatozoa. Milt was diluted 1:49 with 5% dimethyl sulfoxide plus 95% foetal bovine serum for cryopreservation. Computer‐assisted sperm analysis was used to analyse sperm motility, while fertilization and hatching trials were conducted to gauge the applicability of the cryopreservation method for aquaculture. We showed that cooling rates of the dry shipper were stable for 14 days and could be manipulated by the use of different sized freezing straws and use of a simple polystyrene foam container (5 × 5 × 12 cm and 1 cm thickness on all sides with the upper layer exposed). Dry shipper cryopreserved spermatozoa had significantly lower post‐thaw per cent motility and velocity than fresh sperm, but linearity of movement was unchanged. Fertilization and hatching rates were not significantly different at all tested sperm to egg ratios (3000:1–243000:1). The results indicated that 0.33 mL of milt when cryopreserved was sufficient to fertilize up to 450 g of oocytes. Application of this technology will help improve seed production in aquaculture and further develop breeding and genetics studies.  相似文献   
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