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991.
The epidemiology of wheat blast, caused by the Triticum pathotype of Pyricularia oryzae, is poorly understood, making it very difficult to manage. We reported on the individual and combined effect of host resistance and fungicide application for managing wheat blast disease on spikes. Two field experiments (Exp. 1 and Exp. 2) were conducted in a region of Brazil where blast is not known to be endemic to evaluate its development as influenced by fungicide and host resistance. Plots of wheat cultivars BR-18 (partially resistant) and Guamirim (susceptible) were either treated with the fungicide epoxiconazole + pyraclostrobin or left non-treated, and then inoculated with a spore suspension of P. oryzae at mid-anthesis. Spike blast incidence and severity, quantified at regular intervals after inoculation, increased over time, and fungicide and cultivar had statistically significant effects (P < 0.005) on both measures of disease and their temporal rates of progress. Relative to Guamirim-non-treated, BR-18-non-treated (resistance alone) led to 44 and 64% control of final incidence and severity, respectively, in Exp. 1, and 3 and 49% control, respectively, in Exp. 2. Guamirim-treated (fungicide alone) led to 65% control of incidence and 77% control of severity in Exp. 1, and 64% control of incidence and 95% control of severity in Exp. 2. For both incidence and severity, fungicide and resistance alone also reduced the temporal rate of progress relative to the susceptible non-treated. However, the greatest overall efficacy was observed when resistance and fungicide were combined, with over 70 and 90% control of final incidence and severity, respectively, and over 75% reduction in the temporal rate of spike blast progress. Based on percent control, the integrated effect of resistance and fungicide was additive for incidence, severity, and their temporal rates of progress, demonstrating the value of combining the two strategies to manage spike blast. 相似文献
992.
RUVBL2(RuvB-like 2)蛋白是进化上高度保守AAA+(ATPases Associated With Diverse Cellular Activities,AAA)家族成员之一,CHO(Chinese Hamster Ovary)细胞被广泛地用于表达重组DNA蛋白。为探究猪睾丸组织的RUVBL2基因是否能够在CHO细胞中表达,本实验以猪睾丸组织的cDNA为模板,PCR扩增RUVBL2目的基因,并将其克隆至pIRES2-EGFP(Mammalian Expression Vectors pIRES2-EGFP)载体上,进一步转化到DH5α中,再进行PCR、酶切及测序鉴定;将重组质粒转染到CHO细胞中,再进行荧光、RT-PCR、Western blot检测。结果显示:PCR、酶切及测序都证实了RUVBL2基因正确地插入到了载体质粒pIRES2-EGFP的多克隆位点;荧光、RT-PCR、Western blot也证实了RUVBL2基因在CHO细胞中的成功表达。本实验成功构建了猪的pIRES2-EGFP-RUVBL2真核表达载体,并证实了猪睾丸组织中的RUVBL2基因能够在CHO细胞中表达。 相似文献
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995.
为研究从碎米花杜鹃叶中分离得到的化合物原花青素A-1(Proanthocyanidin A-1,简称PAA-1)的免疫增强活性,初步从细胞水平上探讨其免疫增强机制。体外试验采用流式细胞术,检测PAA-1体外对小鼠脾淋巴细胞T细胞亚群CD4和CD8单阳性和双阳性T淋巴细胞亚群百分率及CD4+/CD8+比值;体内试验通过饲喂不同剂量的PAA-1后,检测试验猪外周血淋巴细胞CD4和CD8单阳性以及CD4+/CD8+比值。结果证明,体外试验中同阴性对照组相比,PAA-1能单独或协同Con A提升具CD4+、CD8+及CD4+CD8+表型的T淋巴细胞亚群百分率,提高CD4+/CD8+的比值;体内试验中饲喂中、高剂量的PAA-1的试验猪外周血中具有CD4+、CD8+表型的T淋巴细胞的百分率及CD4+/CD8+的比值均有显著提高。说明PAA-1可通过增加辅助性T淋巴细胞和细胞毒性T淋巴细胞数量、促进T淋巴细胞的成熟以及增加CD4+/CD8+的比值发挥增强细胞免疫的作用,为其进一步开发为新型免疫增强剂提供试验依据。 相似文献
996.
Soy-derived isoflavones have been reported to be specific inhibitors of protein tyrosine kinases like the type 1 insulin-like growth factor receptor (IGF-1R) and the epidermal growth factor receptor (EGFR). This study was conducted to investigate, whether IGF-I and EGF stimulate porcine myoblast growth and whether the responses are influenced by isoflavones. Satellite cell-born myoblasts derived from the semimembranosus muscle of newborn piglets were treated for 26h with IGF-I or EGF alone and in combination with genistein or daidzein. The DNA amount was measured and DNA synthesis was recorded as 6 h-[(3)H]thymidine incorporation during exponential growth in serum-free basal medium. IGF-I and EGF synergistically stimulated DNA synthesis of porcine myoblast with EGF causing a greater response. Genistein (100mumol/l) effectively reduced the growth factor-mediated DNA synthesis, which was associated with an inhibition of growth factor receptor protein expression. In response to daidzein no reduction in growth factor-mediated DNA synthesis was found. Daidzein (1; 10mumol/l) combined with IGF-I caused even a slight increase in DNA amount compared with the untreated control. The expression of the IGF-1R precursor protein was reduced with 10 and 100mumol/l daidzein, whereas the EGFR expression remained unchanged with daidzein. The results suggest that dietary isoflavones may interact with growth factor-induced stimulation of pig skeletal muscle growth. 相似文献
997.
998.
Lupu M Gooley T Zellmer E Graves SS Storb R 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2008,22(1):74-82
BACKGROUND: Preclinical studies of peripheral blood mononuclear cell (PBMC) transplantation conducted in a well-established canine hematopoietic cell transplantation (HCT) model have been successfully translated to human patients over the past 5 decades. OBJECTIVE: We retrospectively investigated the safety and feasibility of PBMC apheresis in the canine model of HCT by analyzing apheresis parameters, cell yields, and the impacts of donor-related and apheresis-related variables on collection yields and donor stability. ANIMALS: One hundred and twenty dogs that underwent PBMC aphereses were evaluated. METHODS: Aphereses were performed with a COBE Spectra blood separator and a central dual-lumen catheter, with or without recombinant canine granulocyte colony-stimulating factor (rcG-CSF) stem cell mobilization. RESULTS: Aphereses from dogs not given rcG-CSF yielded an average volume of 280 +/- 42 mL containing an average of 15,086 +/- 9,834 leukocytes/mL. Aphereses from dogs given rcG-CSF yielded an average volume of 261 +/- 55 mL containing an average of 39,711 +/- 24,488 leukocytes/mL. Higher pre-apheresis white blood cell (WBC) counts correlated with higher apheresis WBC yields (R=0.50, P<.0001). The correlations of collection time, inlet volume, and collection flow rate on WBC yields were statistically significant but only weak to moderate in magnitude (R=0.34, P=.0001; R=0.38, P=.0006; R=0.26, P=.002, respectively) as were the correlations of collection time and inlet volume on collection volumes (R=0.30, P=.002; R=0.42, P<.0001, respectively). All dogs recovered promptly after PBMC aphereses and catheter removal, without complications. CONCLUSIONS AND CLINICAL IMPORTANCE: These data may be useful for translating PBMC apheresis technology to the field of veterinary oncology for the treatment of dogs with hematologic malignancies. 相似文献
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利用废菌渣生产单细胞蛋白饲料研究 总被引:3,自引:0,他引:3
本文以废菌渣为主要原料,利用酿酒酵母(Saccharomyces cerevisiae)和黑曲霉(Aspergillus niger)两菌株进行混合固态发酵生产单细胞蛋白饲料.通过单因素试验和正交试验确定最佳培养条件.结果表明,各因素对粗蛋白质含量的影响为废菌渣与麸皮的比例>培养时间>氮源>水料比;混茵固态发酵的最佳培养条件为废茵渣80%:麸皮20%,硝酸铵2%.尿素1%,KH2PO4 2%,MgSO4·7H2O 1%,水料比为2.5:1,pH为4,接种量为20%,培养时间为120 h时,此时粗蛋白质含量最高,由发酵前的9.61%提高到23.28%. 相似文献