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281.
We investigated the distribution of nitrate reductase activity (NRA) among leaves, roots, culms, twigs, sprouts, culm sheaths, and new leaves of Phyllostachys pubescens Mazel in May, when many sprouts emerge above ground and new leaves of adult culms expand. We found that the NRA differed among parts, and that sprouts showed high NRA. These results indicate that different tissues of P. pubescens vary in nitrate reduction, and sprouts possess high nitrate reduction capacity. We also found that culm sheaths showed high NRA, indicating that they have a high potential for nitrate reduction, even though they are shed in the way of sprout growth.  相似文献   
282.
A series of new C11 cyclopentenones 1–7 was isolated, together with four known metabolites 9/10, 12 and 13, from the extract of the didemnid ascidian Lissoclinum sp. The other didemnid ascidian Diplosoma sp. contained didemnenones 1, 2 and 5, and five known metabolites 8–12. The structures of 1–7 were elucidated by spectroscopic analyses. Cytotoxicity of the isolated compounds was evaluated against three human cancer cell lines (HCT116, A431 and A549).  相似文献   
283.
Focal granulomatous inflammation developed in the livers of five 10-week-old male Sprague-Dawley rats. The characteristic features of this lesion were the presence of foreign body multinucleated giant cells engulfing calcium deposits and site-specific development in a fissure formed in a sub-lobation in the left lobe or interlobar fissure of the medial lobe of the liver. To clarify the pathogenesis of this lesion, rat livers showing abnormal sub-lobation or lobar atrophy, rat livers in an acute dermal toxicity study and guinea pig livers in a skin sensitization test were also examined histologically. Consequently, the present lesion was considered to be a reactive change against calcium that was dystrophically deposited in the area of hepatocellular necrosis due to delayed circulatory disturbance caused by external pressure or extension force. Granulomatous lesions like in the present cases should be differentiated from those caused by evident exogenous pathogens such as chemicals or microorganisms.  相似文献   
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The distribution pattern of collagen fibril diameter in the equine superficial digital flexor tendon (SDFT) is known to differ in central and peripheral areas of some regions. This study reports the essence of collagen fibril differences among different regions of the equine SDFT by transmission electron microscopic (TEM) and high-voltage electron microscopic observations and biochemical analysis. The distribution of large collagen fibrils increased but the density of collagen fibrils decreased from the proximal metacarpal region to the distal metacarpal region. Large collagen fibrils with an irregular cross-sectional profile were found more frequently in the middle metacarpal region than in other regions. Three-dimensional reconstruction of images of irregularly shaped collagen fibrils revealed that these fibrils are formed through fusion of small collagen fibrils with large ones. The amount of decorin, which reportedly inhibits the lateral fusion of collagen fibrils, decreased in the direction of the distal metacarpal region. On the other hand, the size of decorin gradually increased in the direction of the distal metacarpal region. These results suggest that regional differences in collagen fibril distribution and density of collagen fibrils in the SDFT are due, at least in part, to fusion of collagen fibrils and the concomitant regional differences in the amount and size of decorin.  相似文献   
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OBJECTIVE: To evaluate the effects of long-acting insulin on glucose clearance in alpacas. ANIMALS: 8 adult castrated alpacas. PROCEDURE: On 2 days, food was withheld from alpacas for 8 hours. Alpacas were randomly allocated to receive an SC injection of long-acting insulin (0.4 U/kg) or saline (0.9% NaCI) solution 1 hour before the first of 3 administrations of glucose (at 60, 480, and 1,200 minutes after treatment) on day 1 and the alternate treatment and procedure on day 2. Plasma glucose concentration was determined before and 15, 45, 120, and 240 minutes after each glucose administration, and fractional turnover rates were calculated. The data were compared between alpacas with and without insulin administration and among the 3 glucose administrations for each day. RESULTS: Compared with sham-treated alpacas, insulin-treated alpacas had significantly lower blood glucose concentrations from 180 to 600 minutes after treatment; they also had glucose concentrations significantly below baseline values from 120 to 480 minutes, at which time the mean glucose concentration was in the hypoglycemic range. Also, mean fractional turnover of glucose was significantly higher in insulin-treated alpacas from 105 through 300 minutes. CONCLUSIONS AND CLINICAL RELEVANCE: Compared with known effects of regular insulin in alpacas, the action of long-acting insulin was of slower onset but longer lasting; its administration may induce hypoglycemia, even in alpacas that receive glucose. To maintain the hypoglycemic effect, long-acting insulin may have to be administered more than once daily and blood glucose concentration should be monitored to avoid hypoglycemic complications in alpacas.  相似文献   
289.
The genome of porcine circovirus type 2 (PCV2) contains two major open reading frames, which have been shown to encode the virus capsid and replication-associated proteins. The capsid protein is a major structural protein of the virus; it can be a suitable target antigen for detecting PCV2-specific antibodies to monitor PCV2 infection. To produce the antigen, the capsid protein coding sequence was cloned into a baculovirus transfer vector, and a recombinant capsid (rC) protein of PCV2 was expressed as a combined fusion protein in frame with a C-terminal peptide of six histidines. The affinity-purified rC protein was used as coating antigen to develop an ELISA for detecting the virus-specific antibodies in swine sera. The rC protein-based ELISA (rcELISA) was evaluated by examining a panel of 49 PCV2-positive and 49 PCV2-negative swine sera. In comparative experiments of immunoperoxidase monolayer assay (IPMA) using 102 field sera, there was 89.2% coincidence between data obtained by the rcELISA and IPMA. The rcELISA achieved 88.5% specificity and 89.4% sensitivity for detection of PCV2 antibody in the field sera. The assay showed no cross-reactivity with antibodies to PCV type 1, porcine reproductive and respiratory syndrome virus and porcine parvovirus. The results suggest that the rcELISA is suitable for routine serodiagnosis and epidemiological surveys of PCV2-associated diseases.  相似文献   
290.
The effects of delipidation and the oxygen (O(2)) concentration in the atmosphere during culture on in vitro development and H(2)O(2) content were investigated in porcine in vivo fertilized embryos and embryos after in vitro maturation and in vitro fertilization (IVM/IVF embryos). There was no significant difference in the developmental rates to the blastocyst stage between the intact and delipidated IVM/IVF embryos. However, the mean number of cells in blastocysts derived from delipidated IVM/IVF embryos (19.8 +/- 0.8 cells) was significantly smaller than that from intact embryos (24.2 +/- 1.2 cells). Although there were no significant differences in the developmental rates to the blastocyst stage of intact and delipidated IVM/IVF embryos between the cultures under 5% O(2) and 20% O(2), the developmental rate of intact IVM/IVF embryos cultured under 5% O(2) (27.1%) was significantly higher than that of the delipidated embryos cultured under 20% O(2) (19.3%). On the other hand, there was no difference in the developmental rate to the blastocyst stage between in vivo fertilized embryos cultured under 5% O(2) and 20% O(2). Hydrogen peroxide (H(2)O(2)), one of the reactive oxygen species (ROS), is thought to cause damage to embryos. The H(2)O(2) content per embryo derived from oocytes cultured under 5% O(2) (in vivo fertilized, 58.0 +/- 2.5 pixels; IVM/IVF, 79.6 +/- 3.2 pixels) was significantly lower than that (in vivo fertilized, 100.2 +/- 3.8 pixels; IVM/IVF, 103.9 +/- 3.2 pixels) under 20% O(2). Furthermore, the level of H(2)O(2) in delipidated IVM/IVF embryos (94.7 +/- 3.9 pixels) was significantly lower than that in intact embryos (103.9 +/- 3.2 pixels) cultured under 20% O(2). The present results indicate that the delipidation of porcine IVM/IVF embryos and reduction of the O(2) concentration decreased the H(2)O(2) level rather than the in vitro developmental rate to the blastocyst stage.  相似文献   
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