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81.
Electrochemical methods were combined with redox-active surfactants to actively control the motions and positions of aqueous and organic liquids on millimeter and smaller scales. Surfactant species generated at one electrode and consumed at another were used to manipulate the magnitude and direction of spatial gradients in surface tension and guide droplets of organic liquids through simple fluidic networks. Solid microparticles could be transported across unconfined surfaces. Electrochemical control of the position of surface-active species within aqueous films of liquid supported on homogeneous surfaces was used to direct these films into periodic arrays of droplets with deterministic shapes and sizes.  相似文献   
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The adverse effect of estrogenic chemicals on luteinizing hormone-immunoreactive (LH-ir) cells in the adenohypophysis of common carp (Cyprinus carpio) was examined using immunocytochemical and morphometric methods. Adult male fish were collected from two contaminated sites (Ishizu and Wada Rivers) and from a control pond at Agriculture, Food and Environmental Sciences, Research Center of Osaka Prefecture. The concentration of nonylphenol, bisphenol A and 17beta-estradiol in the Ishizu River was 3-4 times higher than that in the Wada River. The proportion and size of LH-ir cells were evaluated using the point-counting method by optical microscopy. In control carp, the proportion of LH-ir cells in the breeding season was significantly lower than in the pre- and post-breeding seasons. The same tendency was also found in Ishizu and Wada River carp, but without statistical significance. The proportion of LH-ir cells in Ishizu River carp was significantly lower than that of the control and the Wada River in all seasons. The LH-ir cells in control carp increased in size in the breeding season. LH-ir cells in Ishizu River carp were significantly (p<0.05) smaller than those in control fish, but not different from Wada River carp. A disturbance in the secretory function of LH-ir cells was found in carp from the Ishizu River; granulation and vacuolation were not in synchronization with those of control and Wada River fish. Our data suggest that the estrogenic chemicals in the Ishizu River interfere with functions of LH-ir cells directly or through the testis.  相似文献   
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OBJECTIVE: To determine the effects of initial handling and training on autonomic nervous functions in young Thoroughbreds. ANIMALS: 63 healthy Thoroughbreds. PROCEDURE: All horses were trained to be handled and initially ridden in September of the yearling year and then trained until the following April by conventional training regimens. To obtain the heart rate (HR), electrocardiograms were recorded in the stable before initial handling and training and following 7 months of training; variations in HR were then evaluated from the power spectrum in terms of the low frequency (LF; 0.01 to 0.07 Hz) power and high frequency (HF; 0.07 to 0.6 Hz) power as indices of autonomic nervous activity. To evaluate the fitness, the V200 (velocity at HR of 200 beat/min), which is reflective of the aerobic capacity of the horse, was measured. RESULTS: Mean (+/- SE) resting HR decreased significantly from 41.5 +/- 0.8 to 38.7 +/- 0.4 beat/min following 7 months of training. The LF power of horses increased significantly from 1,037 +/- 128 milliseconds2 in September of the yearling year to 2,944 +/- 223 milliseconds2 in the following April. Similarly, the HF power increased significantly from 326 +/- 30 milliseconds2 to 576 +/- 39 milliseconds2 at the corresponding time points. The V200 increased significantly following training. CONCLUSIONS AND CLINICAL RELEVANCE: Increases in LF and HF powers indicate that parasympathetic nervous activity increases in horses by 7 months of training. The decrease in resting HR may be dependent on the training-induced increase of parasympathetic nervous activity in Thoroughbreds.  相似文献   
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SUMMARY: A novel bitter amino acid, pulcherrimine was analyzed by reverse-phase high-performance liquid chromatography using a linear gradient elution consisting of methanol/aqueous/acetic acid and methanol/acetic acid mixture, after being labeled with dimethylaminoazobenzenesulfonyl chloride (Dabs-Cl). Linearity of the calibration curve for pulcherrimine was high ( r = 0.994) in the tested range from 0 to 4 μg/mL. By this method, the pulcherrimine content in the ovary and testis of the green sea urchin Hemicentrotus pulcherrimus , collected in the sea off Iwaki in November 1998, was analyzed. The mean pulcherrimine content in the ovary was 1.37 mg/100 g. In contrast, no pulcherrimine was detected in all testes examined. Correlation between the bitterness and the pulcherrimine content was statistically significant. These results strongly support that pulcherrimine is a bitter principle in the green sea urchin ovaries.  相似文献   
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Porcine epidemic diarrhea virus (PEDV) was isolated in Vero cell cultures from the small intestine of a piglet experimentally infected with porcine coronavirus 83P-5, that had been isolated during outbreaks of porcine acute diarrhea and passaged in piglets. The isolation of the PEDV was successful only in Vero cells maintained in the maintenance medium (MM) containing trypsin. Infected Vero cell cultures exhibited CPE characterized by cell-fusion and syncytial formation, as well as cytoplasmic fluorescence when examined by the indirect immunofluorescent test using rabbit anti-83P-5 virus serum. The isolate was adapted to serial propagation in Vero cell cultures by adding trypsin to MM. Vero cell-adapted PEDV was successfully propagated in the MA104, CPK and ESK cell lines in the presence of trypsin in MM. Vero cell-adapted PEDV had morphologic and physicochemical characteristics similar to those of other members of the coronaviridae. The isolate differed serologically from porcine transmissible gastroenteritis (TGE) and porcine hemagglutinating encephalomyelitis viruses, and no antigenic relationship between the isolate and TGE virus could be detected by the indirect immunofluorescent test. Attempts to isolate PEDV in 6 types of primary fetal pig cell cultures and 6 of 10 established cell lines resulted in the failure, probably because these cells were damaged by the action of trypsin.  相似文献   
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The aim of this work was to evaluate the efficiency of the cryoprotectants dimethylformamide and ethylene glycol for cryopreservation of ovine embryos using vitrification and conventional freezing. The recovered embryos were distributed randomly in three treatment groups: Gr. 1: conventional freezing (n = 44), Gr. 2: vitrification with ethylene glycol (n = 39) and Gr. 3: vitrification with dimethylformamide (n = 38). Quality of fresh embryos in control group as well as of frozen and vitrified embryos was examined by three methodologies: staining with propidium iodide and Hoechst 33258 and evaluation under fluorescent microscopy, evaluation of re‐expansion and hatching rates after culture, and determination of apoptotic index with TUNEL technique. It was established that re‐expansion rate in all treatment groups was similar. In the same time, hatching rates were higher in Gr. 1 (40.5%) and Gr. 2 (35.3%) in comparison with Gr. 3 (15.5%, p < 0.05). The number of dead cells in vitrified embryos of Gr. 2 and Gr. 3 was higher (42.6 ± 26.2 and 63.2 ± 34.65, respectively) in comparison with Gr. 1 (conventional freezing, 10.1 ± 8.5, p < 0.05). Embryos vitrified with dimethylformamide included the same quality of apoptotic cells that Gr. 1 (conventional freezing) and fresh embryos. In conclusion, the dimethylformamide and ethylene glycol used as cryoprotectant to vitrify ovine embryos, in the concentrations and exposition time tested in this work, were not as efficient as the conventional freezing for cryopreservation of ovine embryos Thus, the conventional freezing with ethylene glycol was the most efficient method to cryopreserve ovine embryos in comparison with vitrification.  相似文献   
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