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81.
BACKGROUND: Platelet aggregates are a common artifact in canine blood. Aggregates may affect the accuracy of platelet counts, with important consequences for patient care. OBJECTIVES: The purpose of this study was to determine if platelet counts in dogs were more accurate if blood was collected into citrate instead of EDTA as an anticoagulant. METHODS: Blood was collected from 50 dogs with neoplasia admitted to the oncology service at Cornell University. EDTA and citrate Vacutainer tubes were filled with blood in random order. Platelet counts and parameters (mean platelet volume [MPV], platelet distribution width [PDW], mean platelet component concentration [MPC], platelet component distribution width [PCDW], and automated platelet clump count [APCC]) were determined using an optical-based hematology analyzer (ADVIA 120). Blood smears from each anticoagulated sample were scored visually for platelet aggregates. RESULTS: The median platelet count was significantly lower (median decrease, 27 x 10(9)/L) in citrate-anticoagulated blood compared with EDTA-anticoagulated blood. This was attributed to platelet activation and aggregation: significantly more aggregates were seen in smears of citrate- than of EDTA-anticoagulated blood. Aggregates were typically small and not detected by the analyzer. Also, the MPV and MPC (or density) were significantly higher (median increase, 3 fL) and lower (median decrease, 33 g/L) in citrate-anticoagulated samples, respectively. CONCLUSIONS: Platelets aggregate, likely from activation, when blood from dogs with neoplasia is anticoagulated with citrate for hematology testing, resulting in lower platelet counts. Citrate also yields inaccurate results for MPV and MPC, likely because of inadequate sphering of platelets. Thus, we recommend that citrate not be used as an anticoagulant when accurate platelet counts are desired in dogs.  相似文献   
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83.
在常规栽培和优化栽培模式下,分别设置施氮量折合成纯氮0,105,142.5,180 kg/hm2的4个缓释氮肥用量处理,研究了缓释氮肥用量对超级杂交早稻株两优02产量和生理特性的影响.结果表明:在优化栽培模式下,各施氮量处理的产量均高于相应的常规栽培处理,其中纯氮用量142.5 kg/hm2的处理产量最高,而常规栽培各处理的产量则随施氮量的增加而提高;在优化栽培和常规栽培模式下,各时期叶片中的过氧化氢酶(CAT)活性、可溶性糖含量和根系活力均以施氮量180 kg/hm2的处理较高;施用纯氮142.5 kg/hm2的处理乳熟期-成熟期叶片中能保持较高的超氧化物歧化酶(SOD)活性和较低的丙二醛(MDA)含量,有利于延缓水稻功能叶片的衰老.  相似文献   
84.
应用新型植物源生物杀虫剂GF-120,在脐橙和温州蜜柑上进行了防治橘小实蝇的使用浓度和施药方式试验。结果表明,GF-120600倍液和450倍液防治橘小实蝇的效果显著,与50%倍硫磷乳油1500倍液无显著差异,且未见有药害现象,是防治橘小实蝇的理想药剂;点喷法与挂瓶法的防治效果相当。本着简便易行和节约成本的原则,在田间推荐使用GF-120600倍液进行隔株点喷,点喷部位在树冠中下层叶片背面。  相似文献   
85.
【目的】探讨钙信号对小鼠脂肪组织中GPR120基因转录及脂肪生成的影响。【方法】用外源性葡萄糖酸钙和二氢吡啶钙离子通道的阻滞剂Nifedipine处理小鼠30 d,记录小鼠体质量的变化,测定小鼠皮下脂肪、附睾脂肪和肾周脂肪的沉积量,检测血清中甘油三酯(TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C)的浓度,同时利用Real-ti me PCR法分析GPR120基因及与脂肪生成密切相关的转录因子PPARγ、C/EBPα和脂解基因HSL、生脂基因FASmRNA的表达情况,用SPSS软件分析小鼠附睾脂肪中GPR120与脂代谢相关基因表达的相关性。【结果】葡萄糖酸钙可延缓小鼠体质量的增加,减少体脂含量(P0.01),并使小鼠血清中的TG、TC和LDL-C浓度极显著降低(P0.01),HDL-C浓度显著升高(P0.05),可导致GPR120、PPARγ、C/EBPα和FAS的mRNA表达水平降低,且分别达到极显著(P0.01)或显著(P0.05)水平,并可使HSLmRNA表达水平极显著升高(P0.01);Nifedipine处理能使小鼠体质量增加(P0.05),促进体脂沉积(P0.01),并使小鼠血清中的TG和TC浓度显著升高(分别为P0.05和P0.01),GPR120、PPARγ、C/EBPα和FAS的mRNA表达水平极显著升高(P0.01),但却使HSLmRNA的表达水平极显著降低(P0.01)。相关性分析表明,GPR120 mRNA的表达水平与PPARγ、FAS和C/EBPα间呈显著正相关。【结论】钙信号在GPR120调节小鼠脂肪生成的过程中可能起到负调控作用。  相似文献   
86.
通过室内和田间引诱试验,观察不同浓度的GF-120对橘小实蝇成虫的诱杀效果以及对雌、雄两性成虫诱杀效果的差异。结果表明:在室内,GF-120原液与水为1∶4和1∶6(V/V)混合24 h时,诱杀效果最好,1∶2时效果最差;在田间,GF-120原液与水为1∶4时诱杀效果较好,1∶10时效果较差。而在本试验处理中,对橘小实蝇雌雄虫诱杀效果均无显著性差异。  相似文献   
87.
探索BR—120生长调节剂在蔬菜上应用的适宜浓度,对蔬菜和增产增收,具有重要意义。试验结果表明0.01μL/L的BR—120喷施于冬芹菜有显著的增产效果。  相似文献   
88.
分别用25%阿密西达SC、2%菌克毒克AS、4%农抗120AS防治平贝母锈病,与化学农药粉锈宁对比试验。结果表明:阿密西达防效为90.1%;菌克毒克防效为88.1%;农抗120防效为85.2%,粉锈宁防效为74.7%.生物农药防治效果比化学农药提高10.5-15.7个百分点,与对照比较均达到差异显著、极显著水平。  相似文献   
89.
A spinosad-based fruit fly bait, GF-120, has recently become a primary tool for area-wide suppression or eradication of pest tephritid fruit flies. The present study assessed the attraction and feeding of five non-target fly species to GF-120 in Hawaii. These non-target flies include three beneficial tephritid species [Eutreta xanthochaeta (Aldrich), Tetreuaresta obscuriventris (Loew), Ensina sonchi (L.)] introduced for weed biological control, an endemic Hawaiian tephritid [Trupanea dubautiae (Bryan)] (all Diptera: Tephritidae) and the cosmopolitan Drosophila melanogaster Meigen (Diptera: Drosophilidae). All five non-target fly species were susceptible to GF-120, as was the target pest Mediterranean fruit fly Ceratitis capitata (Wiedemann). Feeding on, or even brief tasting of, GF-120 killed all fly species within 2 h. When individual flies were provided with a choice of GF-120 or honey solution, there was no difference in the frequency of first food encounter by E. xanthochaeta, D. melanogaster or C. capitata. The other three non-target species approached honey more often than GF-120 in their first food encounter. Feeding times on GF-120 and honey were not significantly different for D. melanogaster and C. capitata, while the other four non-target species fed longer on honey than on GF-120. There was no significant difference in feeding time on honey versus GF-120 between males and females of each species. These results suggest that area-wide treatment using GF-120 for the purpose of eradication of pest fruit flies has potential negative impacts on these and other non-target fly species in Hawaii.  相似文献   
90.
脂肪酸在动物脂质代谢和免疫调节中起着至关重要的作用,G蛋白偶联受体120(G-protein coupled receptor 120,GPR120)又被称为游离脂肪酸受体4(free fatty acid receptor 4,FFAR4)是G蛋白偶联受体家族成员。它可以被长链脂肪酸激活,参与调节机体糖脂代谢,是治疗人及畜禽脂质代谢紊乱及免疫调节等相关疾病的热点靶点。本文就近来GPR120在脂肪组织中的研究现状、对免疫调节的作用及其激动剂或配体作为药物运用的可能做一综述。  相似文献   
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