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俄罗斯有150多家酒精工厂,工厂平均年产量1万t左右,主要原料为大麦、小麦、玉米和黑麦等。俄罗斯食品生物技术科学研究所是俄罗斯研究酒精生产、酶制剂和酵母的权威机构,该所开发的酒精生产工艺在世界上处于领先地位。其主要技术成果包括:65~80℃低温蒸煮,双酶法糖化,28~38℃中高温快速浓醪发酵,蒸馏废水回用等项技术;其中机械涡流均质是一项有效的节能技术,可节约能耗20%左右。 相似文献
995.
Melanie Kaiser Maria Donatella Semeraro Markus Herrmann Gudrun Absenger Armin Gerger Wilfried Renner 《International journal of molecular sciences》2021,22(13)
Immune functions decline as we age, while the incidence of cancer rises. The advent of immune checkpoint blockade (ICB) has not only revolutionized cancer therapy, but also spawned great interest in identifying predictive biomarkers, since only one third of patients show treatment response. The aging process extensively affects the adaptive immune system and thus T cells, which are the main target of ICB. In this review, we address age-related changes regarding the adaptive immune system with a focus on T cells and their implication on carcinogenesis and ICB. Differences between senescence, exhaustion, and anergy are defined and current knowledge, treatment strategies, and studies exploring T cell aging as a biomarker for ICB are discussed. Finally, novel approaches to improve immunotherapies and to identify biomarkers of response to ICB are presented and their potential is assessed in a comparative analysis. 相似文献
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纳米二氧化硅对纤维固化土力学性质的影响 总被引:1,自引:0,他引:1
为了提高聚乙烯醇纤维-石灰改良土的抗冻性与水稳定性,在改良土中加入纳米Si02,通过试验研究纳米Si02对聚乙烯醇纤维-石灰改良土强度以及抗冻性与水稳定性的影响.试验结果表明,纳米Si02可以有效的提高纤维固化土的抗压强度,当石灰掺量为8%,纳米Si02掺量为1.3%时,土体的抗压强度达到峰值;与单独掺加石灰和单独掺加... 相似文献
999.
Modern therapy of acute myeloid leukemia (AML) began in 1973 with the first report of the successful combination of daunorubicin and cytarabine, which led to complete remission in approximately 45% of patients. Accurate AML diagnosis was dependent on morphology, aided initially only by cytochemistry. Unlike acute lymphoblastic leukemia (ALL), immunophenotyping offered little in the diagnosis of AML, at least during the 1970s and 1980s. The advent of reliable cytogenetics changed the entire prognostic outlook of AML. With karyotypic analysis, different groups of AML could be classified and stratified for various therapies. Unique mutational profiling was a major advance in further categorizing AML patients, aided by the immunophenotypic identification of antigenic markers on the cells. All these advances were occurring as the understanding of the importance of the tumor burden—known as minimal residual disease (MRD)—became crucial for the management of AML patients. The efficacy of MRD has rapidly progressed in the past decade, from a specificity of 10−3 with immunophenotyping to 10−4 with polymerase chain reaction (PCR), which is only appropriate for some patients with AML, and finally to 10−5 or even 10−6 cells with the extraordinary sensitivity of next-generation sequencing (NGS). All of these advances have promoted the concept of personalized medicine, which has led to the advent of targeted agents that can accurately be used for specific diagnostic subtypes. Responses can be predicted and measured accurately. Such targeted agents have now become a cornerstone in the management of AML, increasing efficacy and dramatically reducing toxicity. The focus of this review is on one of the most well-studied targeted agents in AML: the FMS-like tyrosine kinase 3 (FLT3) inhibitors, which have impacted the prognostication and therapeutics of AML. This review selectively discusses the FLT3 inhibitors in detail, as a model for the other burgeoning targeted agents that have already been approved, as well as those that are currently in development. 相似文献
1000.
本研究以蛹虫草发酵液为材料,采用壳聚糖絮凝法和水提醇沉法分别制备了絮凝多糖(XDT)和醇沉多糖(CDT),并对两种方法制备所得多糖的得率、各组分含量、平均粒径和复溶性进行了对比分析,利用扫描电镜、傅里叶红外光谱和刚果红实验对其微观结构、官能团和空间构象进行表征,利用DPPH、超氧阴离子和羟自由基清除能力评价其抗氧化活性,以α-葡萄糖苷酶抑制率评价其降血糖活性,以HepG2细胞增殖抑制率评价其抗肿瘤活性。结果表明:壳聚糖絮凝法制备多糖得率为3.58%,是醇沉法的1.91倍;两种多糖在扫描电镜下的微观结构存在差异,在红外光谱下吸收图谱相似,但XDT比CDT具有更多的三螺旋结构;XDT的平均粒径更小,复溶速度更快;体外抗氧化实验表明,在相同浓度下,对DPPH、超氧阴离子和羟自由基的清除能力,均表现为XDT>CDT;体外抑制α-葡萄糖苷酶活性实验表明,低浓度时,两种多糖的抑制率没有显著性差异,但随着浓度增加,在相同条件下,XDT的抑制活性明显强于CDT;体外抑制肿瘤细胞增殖能力实验表明,在相同处理浓度下,XDT对HepG2细胞的增殖抑制作用优于CDT。综上,壳聚糖絮凝法制备的蛹虫草多糖得率更高、平均粒径更小、复溶性更佳,XDT具备较强的体外抗氧化、降血糖和抗肿瘤活性。 相似文献