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31.
Botryosphaeria panicle and shoot blight was considered as one of the single greatest threats to the California pistachio industry in the last two decades. A large number of fungi with typical morphological characteristics of Botryosphaeriaceae and Diaporthe were collected from pistachios in 18 counties in California and deposited in our culture collection. The aims of this study were to identify these isolates, recognize the distribution of these fungal species and test their pathogenicity to pistachio cultivars. A total of 304 California isolates were identified based on comparisons of DNA sequence data of the ITS, TEF-1α and β-tubulin gene regions, and combined with the morphological features of the cultures and conidia. Research results showed that California isolates represent eight species of Botryosphaeriaceae and one species of Diaporthe. These species include Botryosphaeria dothidea, Diplodia seriata, Dothiorella iberica, Dot. sarmentorum, Lasiodiplodia citricola, L. gilanensis, Neofusicoccum mediterraneum, Neof. vitifusiforme and Diaporthe chamaeropis. Of the Botryosphaeriaceae, 86 % of the isolates were identified as Neof. mediterraneum, which distributed in all the sampled counties. On pistachio trees, in addition to isolates from California, Neof. mediterraneum from Arizona, Neof. australe from Australia, B. dothidea, Neof. parvum and Dia. viticola from Greece were also identified. Pathogenicity of the California fungi on pistachio cultivars, Kerman (female) and Peters (male), using a mycelium plug and conidial suspension inoculation methods showed that all these species are pathogenic to the two tested pistachio cultivars, with L. citricola, L. gilanensis being the most pathogenic species, followed by Neof. mediterraneum. This study represents the first comprehensive work on the species identification, distribution and pathogenicity of Botryosphaeriaceae and Diaporthe on pistachio in California.  相似文献   
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【摘要】〓结直肠癌是常见的消化道恶性肿瘤,传统治疗以外科手术为主,辅以放、化疗,术后5年生存率仅为50%左右。近年来结直肠癌基因治疗备受人们青睐,且有许多研究成果成功运用于临床。目前对结直肠癌基因治的方法主要有原癌基因治疗、抑癌基因治疗、免疫基因治疗以及多基因联合治疗等。  相似文献   
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Background

It has been reported that CD147 and CD98 heavy chain (CD98hc) form a complex on the cell plasma membrane of several cancers; however, whether this complex exists in non-small cell lung cancer (NSCLC) cells and affects the prognosis of patients remains to be elucidated.

Methods

The expression of CD147 and CD98hc was assessed in tissue samples from 241 NSCLC patients and NSCLC cell lines. The correlation between CD147 and CD98hc expression and their association with the prognosis of NSCLC patients were analyzed. We also evaluated the impact of CD147 and CD98hc on the growth of NSCLC cells as well as Akt phosphorylation.

Results

Both CD147 and CD98hc were significantly upregulated in NSCLC cells, and their expression levels were significantly correlated (p < 0.001). Immunoflurenece staining and co-immunoprecipitation demonstrated that CD147 and CD98hc could form a complex on NSCLC cells. Compared with NSCLC patients with CD147?/CD98hc?, those with CD147+/CD98hc+ exhibited a significantly poor overall survival (OS) with a hazard ratio (HR) of 1.92 (p = 0.010), and a significantly increased risk of recurrence with a HR of 1.97 (p = 0.004). Also, we demonstrated that the proliferation of lung cancer cell lines was significantly affected by knockdown and force-expression of the CD147-CD98hc complex. Western blot analysis indicated that the phosphorylation of Akt in NSCLC cells was significantly affected by knockdown and overexpression of either or both CD147 and CD98hc.

Conclusions

Our findings indicate that the CD147-CD98hc complex significantly contributes to poor prognosis of NSCLC patients through promoting cell proliferation via the PI3K/Akt pathway.  相似文献   
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目的:观察升温速度对多孔生物陶瓷孔结构、显气孔率与容重、水渗透率、收缩率以及压缩强度的影响.方法:实验于2005-09/2007-09在武汉理工大学生物中心和重庆邮电大学生物实验中心完成.①在保温时间为2 h,烧成温度为850 ℃条件下,有机泡沫微球与骨料质量配比为0.25时,粘结剂的添加量为20%,升温速度分别为30,60,90,120,150和200 ℃/h条件下,采用有机泡沫微球作为成孔剂的热压铸多孔陶瓷的制备方法制得不同样品.②用电子扫描显微镜观察孔道和表面形貌;根据GB/T1964-1967.1996和GB/T1969~1970-1996测量显气孔率、容重;用自制水渗透率测定仪测定水渗透率;用体积法测定收缩率;用ASTM材料强度测试机测定压缩强度.结果:①升温速度变化对孔径>100 μm大孔的影响明显,对孔径<50 μm小孔的影响不明显,对晶体的长大影响也明显.②随着升温速度从30 ℃/h提高到150 ℃/h,显气孔率从72%增加到82%,容重从0.89×103 kg/m3下降0.52×103 kg/m3,水渗透率从12×10-3 cm2增加到25×10-3 cm2,收缩率27%从减少到23%,抗压强度从17.3 MPa降低到1.59 MPa.结论:升温速度对孔结构、显气孔率与容重、水渗透率、收缩率以及抗压强度有着重要的影响,为了保证成品有较好的孔结构、较高的显气孔率的同时具有一定的机械强度,升温速度选择在120 ℃/h左右较佳.  相似文献   
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Green tea polyphenols are strong antioxidants and can reduce free radical damage. To investigate their neuroprotective potential, we induced oxidative damage in spinal cord neurons using hydrogen peroxide, and applied different concentrations(50–200 μg/mL) of green tea polyphenol to the cell medium for 24 hours. Measurements of superoxide dismutase activity, malondialdehyde content, and expression of apoptosis-related genes and proteins revealed that green tea polyphenol effectively alleviated oxidative stress. Our results indicate that green tea polyphenols play a protective role in spinal cord neurons under oxidative stress.  相似文献   
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