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41.
An 8-year-old chipmunk (Tamias sibiricus) showed a mass on the tail root. Histologically, the excised mass showed proliferation of spindle-to-polyhedral cells and abundant multinucleated giant cells, with the production of neoplastic osteoid. Immunohistochemically, neoplastic cells were positive for vimentin and weakly positive for osteocalcin. Osteoid was also positive for osteocalcin. This tumor was diagnosed as a giant cell-type osteosarcoma. This is the first case report of osteosarcoma in a chipmunk.  相似文献   
42.
A 6-year-old male cross-breed rabbit ( Oryctolagus cuniculus) was presented with lameness and severe swelling from the right shoulder to brachium. On 16-detector helical computed tomography images of the amputated right forelimb after being fixed in formalin, evident proliferative and destructive lesions of bone were observed. On histologic examination, the tumor was composed of proliferating neoplastic cells that resembled histiocytes, with abundant osteoid production. A large number of multinucleated giant cells were found throughout. This case was diagnosed as osteosarcoma by clinical, radiographic, and histologic findings. This is a rare case report of osteosarcoma in a rabbit consistent with canine predilection sites.  相似文献   
43.
漆酶对木质素磺酸盐生物改性的研究   总被引:1,自引:1,他引:0  
本研究由白腐菌液体培养基制得的粗漆酶改性麦麦草木质素磺酸盐。处理后木质素磺酸盐分子量分布明显向高分子量方向移动,木质素磺酸盐溶液的色度随之加深的同时,其分散性能得到明显氡改善,并且在此处理过程中漆酶具有很好的稳定性。  相似文献   
44.
Two complementary DNA (cDNA) libraries were constructed from phyllosomas and hemocytes of adult Japanese spiny lobster Panulirus japonicus and a total of 2,673 expressed sequence tags (ESTs) were obtained. After assembly and clustering, 450 and 458 unique sequences were found from the phyllosoma and hemocyte cDNA libraries, respectively. Of these, 114 and 220 ESTs showed significant homologies with known genes in the National Centre for Biotechnology Information (NCBI) database. The remaining sequences were of unknown function. Immune-related genes found in this study include lectin, proteinase inhibitor, prophenoloxidase, heat-shock protein, antimicrobial peptide, and a few putative defense-related proteins.  相似文献   
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The present study aimed to clarify the effect of timing and type of supplementary grain in grazing dairy cows on herbage dry matter intake (HDMI), nitrogen utilization and milk production. Eight lactating cows were allowed to graze from evening to morning during three seasonal periods (spring, summer, autumn). They were randomly allocated to four treatments (timing: pre‐ (Pre) or post‐grazing (Post), for large grain allotments consisting of 75% of daily grain offered; grain type: barley or corn) in 4 × 4 Latin square designs in each period. In the spring period, HDMI was greater for cows fed corn than those fed barley (P = 0.005), whereas cows in the Pre treatment had a similar HDMI, higher (P = 0.049) urinary purine derivative concentration and greater (P = 0.004) milk yield compared with cows in the Post treatment. In the summer and autumn periods, timing treatments did not affect HDMI, nitrogen utilization or milk production, but cows supplemented with barley had higher urinary purine derivatives concentration (P < 0.05) and milk yield (P < 0.05) compared with those supplemented with corn. The results indicate that large grain allotments immediately before evening grazing during early grazing seasons increased ruminal microbial protein synthesis and milk production without reducing HDMI regardless of grain type.  相似文献   
48.
Genotypic variation in stomatal density and size has been reported but little is known of the genetic mechanisms behind these leaf traits. Using 101 recombinant inbred lines derived from a cross between a tropical japonica, IR69093-41-3-2-2 and an indica variety, IR72, we conducted a field study to determine stomatal density and size and identify quantitative trait loci (QTL) controlling these traits under lowland conditions. Ten QTLs for stomatal density and four QTLs for size were identified across growth stages and leaf surfaces (adaxial and abaxial). The contribution of each QTL to total phenotypic variation ranged from 9.3 to 15.2% for stomatal density and 9.7 to 14.3% for size. The allele from IR72 increased stomatal density and that from IR69093-41-3-2-2 increased size. The expression of the QTLs for stomatal density and size differed by growth stage indicating that these traits might be genetically controlled depending on growth stage or that each QTL had a different function by growth stage. Significant negative genetic correlations between stomatal density and size at both vegetative (r = −0.308**) and heading (r = −0.484**) stages were observed but no common QTL for these traits was detected across growth stages and leaf surfaces. These results indicate that the QTLs for density and size may neither be genetically linked nor pleiotropically controlled and findings can be used as basis for selection at the leaf level on the balance of carbon and water uptake. Further study is needed to fully understand the mechanism underlying the observed genetic association and to elucidate the function of the QTLs involved.  相似文献   
49.
We used various kinds of wasted tea leaves to develop composite sheets with antibacterial properties. Antibacterial tests showed that the number of viable bacterial cells for the sheet containing wasted green tea leaves was around 10:6–107 CFU/ml after 18 h culture compared to 108 CFU/ml for a tea-free sheet. This indicates that cell growth was signifi cantly inhibited. For sheets containing other types of tea leaves (oolong, black, hojicha, and pu-erh), living cells were not found, indicating that these sheets had superior antibacterial effects. Living cells were also not found in sheets containing wasted black tea leaves or roasted tea leaves at a concentration of 60% by weight after 6 h cultivation. Therefore, roasting treatment of wasted green tea leaves was examined to improve the antibacterial activity of the sheet. In particular, the focus was on structural conversion of catechins by heating.  相似文献   
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