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排序方式: 共有599条查询结果,搜索用时 15 毫秒
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作者研究了高温流化α-化工艺中大米淀粉晶粒、水分、绝干淀粉含量、糊化率、脂肪含量、总氮和可降解氮的变化。研究表明:高温流化α-化后淀粉晶粒消失,成松散片状,比表面积增大,有利于酶的作用;水分含量低于10%,可有效防止淀粉老化和微生物污染;高温流化处理后淀粉糊化率与蒸饭法持平,而脂肪与可降解氮含量均明显下降,为酿造淡爽型酿造酒和提高酿造酒非生物性稳定性创造了机会。该工艺尤其适合在我国以糙米为原料的酿造酒生产中推广应用。 相似文献
3.
Sylvia Pietri Jacques R. Séguin Pierre d'Arbigny Katy Drieu Marcel Culcasi 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1997,11(2):121-131
A growing body of evidence supports the trigger role of free radicals in the delayed functional and metabolic myocardial recovery following cardiopulmonary bypass (CPB) in humans, thus opening the field to specific therapies. This clinical study was designed to evaluate, in 15 patients undergoing aortic valve replacement, whether the extent of CPB- and reperfusion-induced lipid peroxidation, ascorbate depletion, tissue necrosis, and cardiac dysfunction is reduced by orally administered EGb 761, a Ginkgo biloba extract withpotent in vitro antiradical properties. Patients received either EGb 761 (Tanakan, 320 mg/day, n = 8) or a matching placebo (n = 7) for 5 days before surgical intervention. Plasma samples were obtained from the peripheral circulation and the coronary sinus at crucial stages of the operation (i.e., before incision, during ischemia, and within the first 30 minutes post-unclamping), and up to 8 days postoperatively. Upon aortic unclamping, EGb 761 inhibited the transcardiac release of thiobarbituric acid species (p ` 0.05), as assessed by high-performance liquid chromatography, and attenuated the early (5–10 minute) decrease in dimethylsulfoxide/ascorbyl free radical levels, an electron spin resonance index of the plasma ascorbate pool (p ` 0.05). EGb 761 also significantly reduced the more delayed leakage of myoglobin (p = 0.007) and had an almost significant effect on ventricular myosin leakage (p = 0.053, 6 days postoperatively). The clinical outcome of recovery of treated patients was improved, but not significantly, compared with untreated patients. Our results demonstrate the usefulness of adjuvant EGb 761 therapy in limiting oxidative stress in cardiovascular surgery and suggest the possible role of highly bioavailable terpene constituents of the drug. 相似文献
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心电信号预处理与心电信号分析 总被引:2,自引:0,他引:2
本文介绍了在一种便携式心电监护仪器中是如何对心电数据进行预处理和智能分析的.为了适应便携式仪器的特征,我们在心电信号预处理中采用了FFT滤波和滑动平均滤波的方法去除各种干扰并使图像得以平滑,同时采用了差分阈值法提取特征点,考虑到监护仪器的实用性,在心电信号分析阶段,我们采用了分析特征间期异常情况的方法来替代对病症的智能诊断功能。 相似文献
6.
采用热休克对新生大鼠心肌细胞进行预处理 ,以诱导αB 晶状体蛋白的表达 ,并观察其对 1mmol·L- 1 的过氧化氢 (H2 O2 )所致心肌细胞损伤的保护作用。发现 :热休克预处理组心肌细胞中αB 晶状体蛋白表达明显增加 ,H2 O2 所致的细胞死亡率及LDH释放率降低 ,总抗氧化能力增强 ;H2 O2 可引起αB 晶状体蛋白从胞浆向胞核及微丝移位。提示热休克预处理的心肌细胞保护作用与其诱导αB 晶状体蛋白的表达增加有关。αB 晶状体蛋白可能通过细胞内移位 ,保护某些核结构 ,稳定细胞骨架 ,并增强心肌细胞抗氧化能力 ,从而发挥其保护作用 相似文献
7.
Bánkfalvi Á Piffkó J Öfner D Dreier R Böcker W Werner K 《Pathology oncology research : POR》1996,2(1-2):71-77
Until recently the only way to rescue masked epitopes in routinely processed surgical pathological material was enzymatic
digestion. The use of heat for antigen retrieval, first by microwave irradiation, represents an important breakthrough in
immunohistochemistry. With the acceptance of microwave oven pretreatment, various modified techniques and alternative heating
methods have also been proposed. Wet autoclave pretreatment for tissue proteolysis is a highly reliable alternative to the
microwave antigen retrieval technique. It provides uniform heating of the slides, hence an even enhancement of staining intensity
in a variety of formalin-sensitive antigens, and it also offers consistent interlaboratory results. The method has been introduced
in routine diagnostic immunohistochemistry for the detection of estrogen-and progesterone receptors, L26-, Ki-67- and bcl-2
antigens and variable types of cytokeratins (1/5/10/11, 8, 13, 19). Experimentally, wet autoclaving can be used very successfully
for the immunophenotyping of p53 and mdm2 expression, for the detection of adhesion molecules (CD44, integrins) and some anti-inflammatory
molecules (annexins), among others. It has produced a substantial improvement in the visualisation of silver-stained nucleolar
organizer regionsassociated proteins (AgNORs) in routine paraffin sections and along with modified silver staining and standardized
AgNOR parameters assessed by image analysis. Wet autoclaving-based AgNOR staining has been proposed by a European multicentric
study group as the standardized method for AgNOR analysis in archival material. 相似文献
8.
Piffkó J Bánkfalvi Á Öfner D Tötsch M Berens A Joos U Böcker W Schmid KW 《Pathology oncology research : POR》1996,2(1-2):37-42
Formalin fixed and paraffin embedded samples from 36 squamous cell carcinomas of the larynx and the oral cavity (pT2N0M0, R0) surrounded by non-tumorous mucosa were studied immunohistochemically using a panel of four different anti-p53 antibodies
(CM1, PAbl801, D07, PAb240), a monoclonal anti-mdm2 antibody and MIB1, following wet autoclave antigen retrieval. P53 immunoreactivity
was detected in 11/14 laryngeal and in 9/22 oral carcinomas. All p53 positive oral, and all but one laryngeal tumors revealed
mdm2 positivity as well, whereas in p53 negative tumors 4/12 and 1/3 mdm2 immunopositive cases were demonstrated, respectively.
MIB1 labeling indices of the tumors ranged between 18% – 64% in p53 positive cases, and 10% – 53% in p53 negative ones. The
difference was not statistically significant. Close spatial coexpression of p53, mdm2 and MIB1 immunoreactivity was observed
at the invasive front of the carcinomas and in the basal and suprabasal layers of the non-tumorous epithelium in all p53 positive
cases. However, the MIB1 expression was similarly increased at the invasive margins in carcinomas lacking immunohistochemically
detectable p53 alterations. Our results strongly suggest that p53 overexpression does not necessarily correspond to increased
rate of proliferation, but rather to mdm2 overexpression and is largely dependent on the anatomical site in case of small
and localized squamous cell carcinomas of the head and neck region. 相似文献
9.
目的:探讨热休克预处理对大鼠心肌细胞凋亡和金属硫蛋白表达的影响.方法:将体外培养的大鼠心肌细胞随机分为3组:对照组(C组)、H2O2损伤组和热休克预处理组,检测心肌细胞的凋亡、心肌细胞Caspase-3活性,并用Western blotting检测线粒体中细胞色素C和金属硫蛋白的表达.结果:与对照组相比,H2O2损伤组心肌细胞凋亡数目增加(P<0.01),Caspase-3活性明显增高(P<0.01),线粒体中细胞色素C和金属硫蛋白的蛋白表达量明显增高(P<0.01),而给予热休克预处理的心肌细胞的凋亡数量和坏死细胞数较H2 O2损伤组明显下降(P<0.01),参与细胞凋亡执行的Caspase-3活性明显降低(P<0.01),细胞色素C和金属硫蛋白的蛋白表达量持续升高(P<0.01).结论:热休克预处理能够抑制心肌细胞凋亡,增加对心肌起保护作用的金属硫蛋白的表达,减少线粒体细胞色素C的释放,从而对心肌细胞起保护性作用. 相似文献
10.
目的分析心脏和肾脏短暂缺血预处理对急性心肌梗死(AMI)后QT间期离散度(QTd)变化的影响.方法观察AMI组(A组)、心脏缺血预处理(MIP)组(B组)和肾脏缺血处理(RIP)组(C组)新西兰兔在AMI前后的QTd,并行心肌电生理诱发室性心动过速(VT),对三组的指标进行比较,同时设假手术组(D组)作对照.结果四组在手术前QTd比较差异无统计学意义(P<0.05);D组手术前后QTd比较差异无统计学意义(P>0.05);在AMI后,B、C二组QTd明显小于A组(P<0.05),而B、C二组QTd比较差异无统计学意义(P>0.05).结论MIP和RIP均可减少AMI后QTd及室胜心律失常的发生,而且二者的作用无明显差异. 相似文献