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51.
浙农大A系意蜂生产性能考察试验报告   总被引:5,自引:0,他引:5  
用杂交一代蜂群进行对比试验的结果表明,浙农大 A 系意蜂的产育力、群势增长速度、采蜜量等,与平湖意蜂和澳大利亚意蜂无显著差异或基本一致,但蜂王浆高产性能表现突出,产量比平湖意蜂高19.5%,比澳意高42.5%,而且质量指标符合国家规定和出口标准。  相似文献   
52.
试验旨在探索使较高比例的淋巴细胞富集在有丝分裂G2/M期的最佳条件。运用植物血凝素(PHA)和刀豆蛋白A(ConA)对淋巴细胞进行刺激使其增殖,培养一定时间后加秋水仙素对淋巴细胞进行同步化处理,用流式细胞仪检测G2/M期的细胞数量进行比对,观察试剂的最佳作用浓度和加秋水仙素的最佳时间。结果表明,采用PHA和ConA刺激淋巴细胞增殖的最佳作用浓度是60和5 μg/mL,且淋巴细胞经ConA刺激培养45 h再加秋水仙素处理5 h G2期的比例最高为58.38%。结果提示,就绒山羊的淋巴细胞来说,ConA刺激绒山羊淋巴细胞增殖的效果比PHA好,且摸索出细胞G2/M期的时间点至关重要。  相似文献   
53.
以单猪屎豆碱(MO)、槲皮素(QU)和环磷酰胺(CY)为参照,观察了狗舌草600mL/L乙醇提取物(EX)对淋巴细胞性白血病L1210细胞体外试验的形态变化;利用流式细胞术,从DNA分子水平上检查了EX对L1210细胞各周期相的影响,探讨EX对L1210细胞的分化机理。结果发现,EX能够使L1210细胞向淋巴细胞方向发展;经EX作用24h后,L1210细胞G0+G1期的百分比较对照组明显升高。提示EX对L1210细胞增殖的抑制作用可能是由于G1期的阻滞所致。  相似文献   
54.
本研究采用田间试验和室内分析相结合的方式,探讨了灌溉次数对青贮玉米的产量和品质的影响。结果表明,随着灌溉次数的增加,青贮玉米产量极显著提高(P <0.01),灌溉3次产量可以增加6倍。灌溉处理青贮玉米的干物质(DM)、粗蛋白质(CP)、碳水化合物(WSC)和淀粉含量有显著差异(P <0.05),灌溉处理显著提高了青贮玉米的MILK 2006奶吨指数8%~11%(P <0.05),与对照相比奶亩指数差异极显著(P <0.01),奶亩指数提高了2.4~5.8倍。玉米青贮饲料发酵品质差异不显著。青贮玉米栽培管理中,适当予以灌溉,可以提高产量改善品质。  相似文献   
55.
T‐cell lymphomas (TCL) are a diverse group of neoplasms with variable diagnostic features, pathophysiologies, therapeutic responses and clinical outcomes. In dogs, TCL includes indolent and aggressive tumours such as T‐zone lymphoma (TZL) and peripheral T‐cell lymphoma (PTCL), respectively. Delineation of molecular subtypes and investigation into underlying pathophysiologies of aggressive TCLs remains inadequate. We investigate the correlations between flow cytometry and histopathology of 73 cases of nodal TCL. The majority of cases (82.2%) were characterized as CD4+ TCL by flow cytometry. Fewer cases were classified as CD8+ TCL (6.8%) or CD4?CD8? TCL (11.0%). All cases, regardless of immunophenotype, exhibited conserved histologic features consistent with the WHO classification of PTCL. Histologic subsets of PTCL corresponding to immunophenotypic features were not identified. Neoplastic cell size determined by flow cytometry correlated significantly with mitotic rate. RNA‐seq was performed on a subset of CD4+ PTCL cases (n = 6) and compared with sorted control CD4+ T‐cells. The gene expression pattern of CD4+ PTCL was similar between all cases regardless of breed. PTCL was enriched in pathways representing G‐coupled protein receptor signalling, extracellular matrix remodelling and vascular development, immune signalling and mitotic activity. Furthermore, global gene expression changes were consistent with downregulation of PTEN signalling and upregulation of the MTOR‐PI3K‐ATK axis. In this study, we evaluated the correlations between flow cytometry, histopathology and gene expression within a large cohort of nodal TCLs. We further demonstrate the ability of flow cytometry to identify a subtype of T‐cell lymphoma, CD4+ PTCL, with a uniform histomorphology and gene expression profile.  相似文献   
56.
塞内卡病毒A(SVA)作为一种新发病病原,致病机制仍不清楚。通过显微镜观察发现,SVA感染PK-15细胞后能使细胞产生明显的细胞病变(CPE),同时伴随着严重的细胞凋亡。为了深入研究SVA诱导凋亡的情况,在验证SVA各蛋白真核质粒正常表达后,通过Annexin V-FITC/PI双染流式方法检测SVA各蛋白诱导凋亡的情况,Annexin V-FITC/PI和Hoechst染色后显微镜观察磷脂酰丝氨酸和核凝聚程度,通过Western blotting和RT-PCR技术分析SVA-VP1对凋亡通路中主要调控分子Caspase3、Caspase8和Bax蛋白质和mRNA水平的影响,发现SVA-VP1能够显著诱导细胞发生早期和晚期凋亡,并且能够促进凋亡蛋白Caspase3、Caspase8及Bax蛋白和mRNA水平的上调。本研究结果为深入研究SVA调控宿主细胞凋亡的分子机制和致病机制奠定了理论基础。  相似文献   
57.
Background: In veterinary medicine, there is increasing interest in measuring C‐reactive protein (CRP) as a tool for diagnosis and monitoring of inflammatory diseases. Reported CRP concentrations for healthy dogs have ranged from 0 to 8.9 mg/L. Objectives: The aims of this study were to evaluate a canine‐specific point‐of‐care (POC) lateral flow immunoassay for qualitative CRP measurement in healthy and diseased dogs and to compare results with those obtained by a quantitative ELISA. Methods: Blood samples from 73 client‐owned dogs were available for testing: 16 healthy dogs and 57 dogs with a variety of infectious, inflammatory, or neoplastic diseases. CRP was measured in heparinized whole blood samples and serum with the TECOmedical Dog CRP‐visual POC test. A red line develops in the POC device if CRP is ≥5 mg/L, and results are scored as negative or positive. An ELISA validated previously for canine serum was used as the reference method. Results: For all dogs, serum CRP concentrations measured by the ELISA ranged from 0.1 to ≥350 mg/L (median=38 mg/L). Percentages of the CRP POC test results that agreed with the ELISA results were 98.6% for whole blood and 97.3% for serum samples. For serum samples, sensitivity of the POC test was 96.4% and specificity was 81.3%. For whole blood, sensitivity was 94.7% and specificity was 93.8%. Conclusions: The POC test had very good agreement with the ELISA test and had high sensitivity and specificity; therefore, it can be used as a qualitative test to screen for increases in CRP concentrations.  相似文献   
58.
灌水对沙漠绿洲区甘草生长动态和产量的影响   总被引:1,自引:1,他引:1  
蔺海明  纪瑛  邱黛玉 《草业科学》2011,28(11):1992-1997
为研究灌水对沙漠绿洲区甘草(Glycyrrhiza uralensis)生长动态和产量的效应,本研究设2 700(W1)、3 600(W2)、4 500(W3)、5 400(W4)、6 300(W5)和7 200(W6) m3/hm2 6个灌水处理。结果表明,灌水明显促进甘草茎叶、根的生长。处理W4、W5和W6株高显著高于W1、W2和W3(P<0.05),主茎生长速度W6处理较W1快60%,较W2快33%;W3、W4、W5和W6处理地上部干质量显著高于W1(P<0.05),干物质积累速度W3处理较W1快11%;根长、芦径、根干质量随灌水量增加而增加,灌水量超过5 400 m3/hm2则表现下降趋势,处理W3和W4根干质量最高,在根快速生长期W3和W4处理的一年龄和二年龄根干质量增加速度分别较W1快50%和35%。灌水4 500和5 400 m3/hm2,一年龄甘草和二年龄甘草根产量均达到较高水平,但前者灌水效率较后者高,可节水900 m3/hm2。  相似文献   
59.
In order to increase the reproductive indices of capercaillie kept in closed breeding facilities, it is necessary to constantly expand the methods of better understanding the characteristics of sperm and their fertilizing potency. The aim of the study was to analyse selected features of capercaillie sperm using flow cytometry and their connection with fertility results. The study included five males, three of which were kept in a family group with eight females and two were kept alone. For sperm viability, acrosome integrity, mitochondrial potential and DNA defragmentation were assessed. Paternity analyses were performed in order to confirm the paternity of the individual and to link the evaluated semen traits with reproductive success. Analyses carried out in the flow cytometer showed any significant differences between males in sperm characteristics. In the semen of male No. 101, the father of all chicks from the analysed family group, 91.3% of live sperm, 91.5% with intact acrosome, 83.6% with active mitochondria and 2.0% with DNA defragmentation were observed. The average fertility rate was 71.0%, and chick hatchability was 100%. Using flow cytometry in the analysis of capercaillie semen and its connection with the results of natural mating, we were able to obtain deeper knowledge about new sperm characteristics that were not examined before and which in the future may be helpful in selecting males for the reproductive flocks and developing assisted reproduction techniques.  相似文献   
60.
The objectives of the study were to evaluate haemodynamic changes and their relationships among ipsilateral (IPS) and contralateral (CONT) uterine arteries (UA) during different stages of pregnancy in Bos indicus cows. Multiparous pregnant cows (n = 40) having a gestation length 30.47 ± 0.54 (mean ± SD) days were randomly enrolled and subjected to Doppler ultrasonography sequentially at 1st, 2nd, 4th, 6th and 8th months of gestation. Blood flow indices including diameter of UA (mm), blood flow volume (BFVo, ml/min), blood flow velocity (BFVe, cm/s), time-averaged maximum velocity (TAMV, cm/s), pulsatility index (PI) and resistance index (RI) were recorded. Data were analysed with mixed models using the PROC MIXED procedures, and Pearson correlation coefficients were calculated using the PROC CORR statement in SAS. The final statistical models included the fixed effects of side of UA, gestation month and the interaction between side of UA and gestation month. Results revealed that the mean diameter of the UA (12.13 ± 0.22 vs. 10.09 ± 0.22), BFVo (1236.33 ± 0.55 vs. 770.41 ± 0.55), BFVe (17.18 ± 0.42 vs. 15.58 ± 0.42) and TAMV (17.11 ± 0.44 vs. 15.77 ± 0.44) was higher (p < .05) in IPS as compared to CONT side of the UA in cows. However, PI and RI did not differ between IPS and CON arteries of uterus in cows. A very high and positive correlation (r = .89; p < .05) existed between the diameter of UA and BFVo starting from 1st to 8th months of gestation in IPS as well as CONT sides of UA. Moreover, TAMV was highly and positively correlated (r = .91; p < .05) with BFVe throughout the gestation. In conclusion, these haemodynamic changes in the UA could be used as a valuable validity tool to differentiate the compromised pregnancy in Bos indicus cows.  相似文献   
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