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451.
The complete sequence of the two RNAs of a furovirus isolate from durum wheat in Italy was determined. Sequence comparisons and phylogenetic analysis were done to compare the Italian virus withSoilborne wheat mosaic virus (SBWMV) from the USA and with furovirus sequences recently published asEuropean wheat mosaic virus (EWMV), from wheat in France, andSoilborne rye mosaic virus (SBRMV), from rye and wheat in Germany. Over the entire genome, the Italian isolate RNA1 and RNA2 had respectively 97.5% and 98.6% nucleotide identity with EWMV, 95.5% and 85.8% with SBRMV-G and 70.6% and 64.5% with SBWMV. The Italian isolate was therefore clearly distinct from SBWMV The European isolates all appear to belong to the same virus and the nameSoilborne cereal mosaic virus may resolve earlier ambiguities.  相似文献   
452.
α-Fetoprotein (AFP) is a diagnostic marker for the presence of hepatocellular carcinoma, and a potential target for immunotherapy. Unfortunately, the immunity to AFP is presumably difficult to elicit because of immune tolerance acquired during the development of immune system. In the present study, we used AFP as a model antigen to explore the feasibility of the immunotherapy of AFP-positive liver cancer by the breaking of immune tolerance against AFP in a cross-reaction between the xenogeneic homologues and self molecules. Recombinant rat AFP was prepared as a vaccine, and mouse AFP was prepared as a control. Immunized with rat AFP was effective at protective and therapeutic antitumor immunity in hepatocellular carcinoma model in mice. Both humoral and cellular immune responses may be responsible for the antitumor activity against AFP-positive tumor cells, and no marked side effects were observed in the immunized mice. Thus, our study may provide an effective vaccine strategy for the treatment of AFP-positive hepatocellular carcinoma, and may be of importance to further exploration of the breaking of immune tolerance to self molecules.  相似文献   
453.
快速检测植物类囊体膜蛋白体内磷酸化的方法   总被引:4,自引:0,他引:4  
借助特异的磷酸蛋白探针,建立了快速检测植物类囊体膜蛋白体内磷酸化的方法,可以检测到光照处理的豌豆叶圆片类囊体膜中8条磷酸化蛋白带存在,它们的分子质量分别为65、45、36、33、30、29、20和10 ku.进一步使用光系统Ⅱ反应中心蛋白和捕光色素复合物Ⅱ(LHCⅡ)的特异抗体,确定了上述磷酸化蛋白的归属,分别是磷酸化D1和(或)D2的聚合体(65 ku)、CP43(45 ku)、D2(36 ku)、D1(33 ku),LHCB1(30 ku),LHCB2(29 ku)和psbH gene产物(10 ku),20 ku小肽尚不清楚其来源.并与其他几种检测磷酸化蛋白的方法进行了比较.  相似文献   
454.
球孢白僵菌高壳聚酶突变株的筛选   总被引:16,自引:0,他引:16  
以球孢白僵菌(Beauveria bassiana)1316为出发菌株,通过紫外线和高能电子束分别诱变分生孢子,采用平板透明圆法初筛和摇瓶培养复筛的方法,经3轮诱变,筛选到5株高产突变株。其中一株最高产的定名为Beauveria bassiana 1316-V1,其壳聚糖酶活力是原始菌株的16倍;而且经传代培养,其高产特性能够稳定遗传。  相似文献   
455.
研究了潭江流域典型区中小尺度森林碳库与人类活动化石能源碳释放.结果表明,自1990年 以来,森林一直起着碳汇的作用,并且随着经济发展与时间延长,汇的作用得到加强,1990 年森林净吸收碳量为1.0579×107 t,到2002年森林净吸收碳量增至1.28061×107 t,年平均净吸收碳量为1.856×105 t.化石能源的碳释放与经济增长呈正相关,1990年的化石能源碳排放为9.508×105 t,2002年为1.8562×106 t,年平均增加量7.0×104 t,2003年达到2.1968×106 t,比2002年增加3.406×105 t.2002年,潭江流域万元GDP能耗为2.21 t标煤,高于珠江三角洲平均水平.如果提高能源利用效率,使能耗降低至平均水平,则可削减3.360×105 t碳排放,大于2002年流域森林净吸收的碳量. 从流域净吸收与净增排放的碳量来看,流域碳平衡与人类活动的关系有待进一步研究.  相似文献   
456.
BackgroundThe prevalence of cardiovascular disease (CVD) has been increasing in children, adolescents, and young adults in recent decades. Exposure to adverse intrauterine environment in fetal life may contribute to the elevated risk of early-onset CVD. Many studies have shown that maternal hypertensive disorders of pregnancy (HDP) are associated with increased risks of congenital heart disease, high blood pressure, increased BMI, and systemic vascular dysfunction in offspring. However, empirical evidence on the association between prenatal exposure to maternal HDP and early-onset CVD in childhood and adolescence remains limited.Methods and findingsWe conducted a population-based cohort study using Danish national health registers, including 2,491,340 individuals born in Denmark from 1977 to 2018. Follow-up started at birth and ended at the first diagnosis of CVD, emigration, death, or 31 December 2018, whichever came first. Exposure of maternal HDP was categorized as preeclampsia or eclampsia (n = 68,387), gestational hypertension (n = 18,603), and pregestational hypertension (n = 15,062). Outcome was the diagnosis of early-onset CVD from birth to young adulthood (up to 40 years old). We performed Cox proportional hazards regression to evaluate the associations and whether the association differed by maternal history of CVD or diabetes before childbirth. We further assessed the association by timing of onset and severity of preeclampsia. The median follow-up time was 18.37 years, and 51.3% of the participants were males. A total of 4,532 offspring in the exposed group (2.47 per 1,000 person-years) and 94,457 in the unexposed group (2.03 per 1,000 person-years) were diagnosed with CVD. We found that exposure to maternal HDP was associated with an increased risk of early-onset CVD (hazard ratio [HR]: 1.23; 95% CI = 1.19 to 1.26; P < 0.001). The HRs for preeclampsia or eclampsia, gestational hypertension, and pregestational hypertension were 1.22 (95% CI, 1.18 to 1.26; P < 0.001), 1.25 (95% CI, 1.17 to 1.34; P < 0.001), and 1.28 (95% CI, 1.15 to 1.42; P < 0.001), respectively. We also observed increased risks for type-specific CVDs, in particular for hypertensive disease (HR, 2.11; 95% CI, 1.96 to 2.27; P < 0.001) and myocardial infarction (HR, 1.49; 95% CI, 1.12 to 1.98; P = 0.007). Strong associations were found among offspring of mothers with CVD history (HR, 1.67; 95% CI, 1.41 to 1.98; P < 0.001) or comorbid diabetes (HR, 1.56; 95% CI, 1.34 to 1.83; P < 0.001). When considering timing of onset and severity of preeclampsia on offspring CVD, the strongest association was observed for early-onset and severe preeclampsia (HR, 1.48, 95% CI, 1.30 to 1.67; P < 0.001). Study limitations include the lack of information on certain potential confounders (including smoking, physical activity, and alcohol consumption) and limited generalizability in other countries with varying disparities in healthcare.ConclusionsOffspring born to mothers with HDP, especially mothers with CVD or diabetes history, were at increased risks of overall and certain type-specific early-onset CVDs in their first decades of life. Further research is warranted to better understand the mechanisms underlying the relationship between maternal HDP and early-onset CVD in offspring.

Chen Huang and co-workers study associations between maternal hypertensive disorders and cardiovascular disease in offspring.  相似文献   
457.
Novozyme 435 could catalyze efficient acylation of 3-n-butylphthalide in organic medium. The conversion of 3-n-butylphthalide increased with the increase of hydrophobicity of solvent below that of hexane. The more available solvent was hexane. Salt hydride could control fixed water activity. The optimum water activity was 0.62. And the optimum of reaction time, velocity of agitation, dosage of Novozyme 435 and acetic anhydride to 3-n-butylphtrhalide molar ratio were 48 hours, 150 rpm, 8 mg/mL and 8:1, respectively. The conversion of 48.9% could be obtained at a water activity of 0.62 in hexane. Furthermore, Novozyme 435 had an enantioselective acylation of racemic 3-n-butylphthalide by original analysis.  相似文献   
458.
Verticillium wilt is a disastrous disease causing significant yield losses of many crops. Isolation of verticillium wilt resistance gene is a fundamental work for controlling this disease through genetic engineering. In this report, we describe the cloning and characterization of a Ve like gene (StVe) from Solanum torvum Swartz. The nucleotide sequence of StVe is 3640 bp long with an open reading frame of 3414 bp encoding a protein precursor of 1138 aa. Sharing high homologies to tomato verticillium wilt disease resistance genes Ve1 and Ve2, the leucine rich (15.89%) protein StVe has a calculated molecular weight of 126.48kDa with an isoelectric point of 5.62. It possesses a hydrophobic N-terminal signal peptide of 20 aa and 38 predicted leucine-rich repeats containing 32 potential N-glycosylation sites (28 being significant). Fifty-seven predicted phosphorylation sites (36 for S, 8 for T and 13 for Y) distribute in StVe protein. A PEST-like sequence and a mammalian endocytosis signals YCVF are found within the C-terminal region. The C terminus of StVe concludes with the residues KKF similar to the KKX motif that confers endoplasmic reticulum localization in plants as well as mammals and yeast. The sequence analysis of the StVe gene implies that the StVe is a potential verticillium wilt disease resistance gene encoding a cell surface-like receptor protein.  相似文献   
459.
460.
Tong A  Wu L  Lin Q  Lau QC  Zhao X  Li J  Chen P  Chen L  Tang H  Huang C  Wei YQ 《Proteomics》2008,8(10):2012-2023
Hepatitis B virus (HBV) is one of the major etiological factors responsible for acute and chronic liver disease and for the development of hepatocellular carcinoma (HCC). To determine the effects of HBV replication on host cell-protein expression, we utilized 2-DE and MS/MS analysis to compare and identify differentially expressed proteins between an HBV-producing cell line HepG2.2.15 and its parental cell line HepG2. Of the 66 spots identified as differentially expressed (+/- over twofold, p <0.05) between the two cell lines, 62 spots (corresponding to 61 unique proteins) were positively identified by MS/MS analysis. These proteins could be clearly divided into three major groups by cluster and metabolic/signaling pathway analysis: proteins involved in retinol metabolism pathway, calcium ion-binding proteins, and proteins associated with protein degradation pathways. Other proteins identified include those that function in diverse biological processes such as signal transduction, immune regulation, molecular chaperone, electron transport/redox regulation, cell proliferation/differentiation, and mRNA splicing. In summary, we profiled proteome alterations between HepG2.2.15 and HepG2 cells. The proteins identified in this study would be useful in revealing the mechanisms underlying HBV-host cell interactions and the development of HCC. This study can also provide some useful clues for antiviral research.  相似文献   
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