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91.
ABSTRACT:   The present study aimed to investigate functional changes of the kidney in mature masu salmon. The urine flow rate (UFR), kidney-somatic index (KSI), and epithelial cell height of second proximal convoluted segment of renal tubules were examined in mature and immature masu salmon Oncorhynchus masou . Two methods of calculating UFR were made as either the units per body weight, or body weight without gonads. The former calculation using body weight may be used for comparison between data obtained from immature fish, and the latter method was suitable when comparing mature sexes and assessing the transition from immature to finally mature stages. In both calculations of UFR, KSI, and epithelial cell height of the second proximal segment, the values for mature fish were significantly higher than for immature fish. These results first suggest that functional transition of the kidney occurs in maturing fish.  相似文献   
92.
Angiosperm trees bend their stems by forming tension wood at the upper side of leaning stems. Most tension wood has a cellulose-rich G-layer in the innermost surface of the fiber cell wall. Strong tensile stress is considered to occur in the G-layer. This study undertook to identify the proteins involved in G-layer formation and function through a proteomic analysis of G-layer-localized protein. G-layers of poplar were loosened by sonication and isolated as doughnut-shaped pieces of thinly sliced transverse sections. The proteins, once extracted with urea/detergent solution, were separated by two-dimensional polyacrylamide gel electrophoresis, and 110 spots were subjected to liquid chromatography tandem mass spectrometry (LC/MS/MS). A database search for these spots’ mass spectrum patterns identified 72 proteins. In addition, all peptide digestion mixtures of G-layer proteins were separated by strong cation exchange chromatography and 39 proteins were identified using LC/MS/MS analysis. Proteins involved in wall formation, such as lignin biosynthesis-related protein, xyloglucan endotransglucosylase, and fasciclin-like arabinogalactan protein, were notably detected in the G-layer.  相似文献   
93.
Abstract

Yacon (Polymnia sonchifolia) plants originating from Andean highlands are known to accumulate a large amount of oligofructans in their tubers and tuberous roots (Ohyama et al. 1990; Asami et al. 1992). Asami et al. (1992) have reported that tubers and tuberous roots which were harvested in late fall contained about 57 and 66% respectively (on a dry matter basis) of oligofructans. However, the tubers, tuberous roots and shoots of the yacon contained only a small amount of starch and inulin. The tuberous roots of yacon which resemble those of sweet potato in appearance are usually eaten raw and are expected to become commercially valuable as a source of oligofructans.  相似文献   
94.
The characteristics of Cs accumulation and localization in edible mushrooms were examined using the mycelia of Pleurotus ostreatus-Y1. Scanning electron microscope images revealed the existence of white spots, and energy dispersive X-ray microanalyzer analysis indicated the presence of larger amounts of Cs and P in these spots in mycelia cultured on medium containing 25 mM CsCl. The (137)Cs activities in the mycelia were approximately 4-6 times higher than those in water used for (137)Cs elution. Higher Cs concentrations in the sediment fraction including vacuolar pellets were obtained compared to the upper fractions. It was observed that yellowish spots caused by the fluorescence of 4',6-diamidino-2-phenylindole (DAPI)-stained polyphosphate were localized in the mycelia. The higher fluorescence intensity of the yellowish-grained spots was measured in comparison with other regions in the mycelium. These results suggested that Cs in the mycelia was trapped by polyphosphate in vacuoles or other organelles.  相似文献   
95.
The action of avermectin was studied in the leg muscle and the central nervous system of the American cockroach, Periplanata americana L. Avermectin at a low concentration (10?7M) causes a failure of the leg muscles to respond to external stimuli within 30 min without affecting the magnitude of contraction. Avermectin was found to stimulate Cl? uptake by the leg muscles within 4 min at 10?7M. The threshold concentration to cause such stimulation was on the order of 10?8M. This stimulatory action could be antagonized by picrotoxinin (10?4M) and to a lesser extent by bicuculline methiodide (10?4M). The phenomenon is observable under both Na+-free and K+-free conditions. It was concluded that the action of avermectin is to open the chloride channel on the plasma membrane. This action of avermectin does not seem to be mediated through GABA, GABA receptors, diazepine receptors, or picrotoxinin receptor in this insect species, and therefore suggests that avermectin directly attacks the chloride channel proper both in the central nervous and the neuromuscular systems.  相似文献   
96.
The purpose of this observational study was to determine the characteristic computed tomographic (CT) myelography findings of cervical vertebral stenotic myelopathy (CVSM) lesions in Thoroughbred horses. A total of 23 Thoroughbred horses (age range, 155–717 days on CT examination; mean, 410.9 days) were analyzed. All 23 Thoroughbred horses underwent unenhanced radiography, radiographic myelography, and CT myelography. Unenhanced radiographs were observed the presence of cervical vertebral malalignment and osseous lesions. Radiographic myelograms were observed for signs of cervical spinal cord compression; additionally, CT myelograms were used to detect cervical vertebral osseous lesions. Ventral compressions were frequently observed in the cranial cervical vertebrae (C2–C4), whereas dorsal compressions were frequently observed in the caudal cervical vertebrae (C5–C7). Furthermore, osseous lesions of the caudal articular process developed more frequently than those of the cranial articular process. CT myelography in Thoroughbred horses is a useful method for detecting CVSM changes.  相似文献   
97.
The estimated allele frequency at neutral DNA marker loci is a fundamental parameter for establishing a conservation scheme for a set of livestock breeds. In this study, we propose a novel 'minimum distance (MD) method' for estimating neutral allele frequencies, which minimizes the error by the use of pedigree information. Using computer simulation and actual microsatellite data for a pedigreed cattle population, the performance of the proposed method was compared with that of conventional random sampling (RND). MD manifests a promising superiority to RND, irrespective of the sample size and the depth of pedigree. It is theoretically demonstrated that the error of the estimates depends on both the sample size and the distance of founder allele frequencies between the sampled and the non-sampled individuals. MD samples individuals so as to minimize the latter source of estimation error.  相似文献   
98.
OBJECTIVE: To investigate the relationship between velocities of pulmonary venous flow (PVF) and plasma concentrations of atrial natriuretic peptide (ANP) in healthy dogs. ANIMALS: 7 healthy Beagles. PROCEDURES: Dogs were anesthetized, intubated, and positioned in left lateral recumbency. Lactated Ringer's solution was infused (200 mL/kg/h) for 60 minutes via a cephalic vein. Transmitral flow and PVF velocities were measured echocardiographically by use of the apical 4-chamber view. Pulmonary capillary wedge pressure (PCWP) and ANP concentrations were determined. RESULTS: IV infusion significantly increased heart rate and PCWP. Similarly, the ANP concentration significantly increased from baseline (before infusion of lactated Ringer's solution) values. Transmitral flow velocities were significantly increased, although the ratio of velocity of the flow during early ventricular diastole (E wave) to velocity of the atrial flow (A wave; E:A ratio) was unchanged. Regarding the PVF velocities, forward flow during ventricular systole (S wave) and retrograde flow during atrial contraction were significantly increased, whereas velocity of the forward flow during ventricular diastole (D wave) was unchanged. Ratio of the velocity of the S wave to velocity of the D wave was increased significantly, and this ratio was significantly correlated with PCWP or ANP concentration. However, the E:A ratio was not correlated with PCWP or ANP concentration. CONCLUSIONS AND CLINICAL RELEVANCE: PVF velocities were strongly correlated with PCWP and plasma ANP concentration in clinically normal dogs. Therefore, PVF velocities may serve as a sensitive indicator and provide additional information for monitoring acute preloading conditions and estimating atrial filling abnormalities in dogs.  相似文献   
99.
OBJECTIVE: To evaluate tissue Doppler imaging (TDI) of the left ventricular (LV) free wall (FW) and ventricular septum (VS) as an indicator of LV systolic function in dogs. ANIMALS: 7 healthy Beagles. PROCEDURES: Doses of dobutamine (5 and 10 microg/kg/min) and esmolol (50 and 100 microg/kg/min) were infused into the LV of each dog. With each dose, heart rate; myocardial performance index (MPI); transmitral inflow and ejection time (determined via pulsed-wave Doppler [PWD] echocardiography); and FW and VS velocities of the mitral valve annulus (determined via TDI during systole [S'], early diastole [E'], and late diastole [A']) were assessed. RESULTS: With each dose, dobutamine significantly increased heart rate and the first derivatives of LV pressure (+dP/dt and -dP/dt), whereas esmolol significantly decreased the +dP/dt and -dP/dt values, compared with baseline. Esmolol (100 microg/kg/min) significantly decreased the VS-TDI-derived S' velocity and FW-TDI-derived E' velocity; dobutamine significantly increased transmitral inflow and TDI velocities. Regression coefficient between VS-TDI-derived S' velocity and +dP/dt was higher than that between FW-TDI-derived S' velocity and +dP/dt. Compared with baseline, the PWD- and VS-TDI-derived MPI were significantly decreased by dobutamine and significantly increased by esmolol at each dose. Values of FW-TDI-derived MPI were higher than values derived via the other techniques. Correlation between +dP/dt and VS-TDI-derived MPI was greater than that between +dP/dt and FW-TDI- or PWD-derived MPI. CONCLUSIONS AND CLINICAL RELEVANCE: In healthy dogs, the VS-TDI-derived S' velocity and MPI appear to be reliable assessments for evaluating LV systolic function.  相似文献   
100.
In this study values for total cholesterol and triglycerides were measured in 110 blood samples taken from 360 days pre-partum to 90 days post-partum in ten parturitions of six bottlenose dolphins, and in 75 blood samples when the dolphins were not pregnant as a control group. The average total cholesterol values in the second, third and fourth stages and in the puerperium were significantly higher than the average value of the control group by 11.0%, 30.2%, 19.3% and 13.4% respectively. The average triglycerides values for the third and fourth stages and in the puerperium were also significantly higher than those in the control group by 59.7%, 84.3%, and 42.1% respectively.  相似文献   
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