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191.
目前对于生物质成型燃料替代散煤减排效果的现场评估还非常缺乏,且均为基于短时间测试方法,无法反映炉具全天实际排放情况。该研究以黑龙江省某生物质成型燃料及配套炉具推广示范村为例,采用全天24 h实地测试的方法,研究了该地区的燃煤炉具以及推广的自动进料和手动进料生物质炉具的污染排放情况。结果表明:自动/手动进料生物质炉具相比燃煤炉具的PM2.5、CO、SO2排放因子分别降低41.2%、54.3%、40.0%和35.3%、22.1%、20.0%,NOx的排放因子没有降低。对不同取暖方式的户均排放总量核算发现:自动/手动进料生物质炉具排放的PM2.5、CO、SO2分别减排39.79%、52.77%、41.35%和33.41%、19.38%、27.01%;NOx分别升高46.14%和6.69%。此外,调研发现经济性和便利性是生物质炉具推广的重要影响因素。  相似文献   
192.
3β-hydroxysterol △24-reductase (DHCR24) catalyzes the conversion of desmosterol to cholesterol and in turn affects lipid metabolism. DHCR24 is a multifunctional protein with enzymatic activity, antioxidant stress, scavenging of reactive oxygen species (ROS) and anti-apoptotic effects. Hepatitis C virus (HCV) infection results in severe oxidative stress which is correlated closely with fatty liver, liver cirrhosis, liver cancer and a series of liver diseases. Recent studies have shown that DHCR24 expression is regulated by various factors such as sterols, hormones and growth factors, and the expression of DHCR24 is significantly increased after HCV infection. In-depth study of the function and regulation of DHCR24 and its relationship with disease can be help to further discover and understand the pathogenesis, and contribute to early diagnosis and treatment of disease. This review summarizes the regulation of DHCR24 expression and its progress with HCV infection.  相似文献   
193.
美系短角肉种牛的全日制放牧管理   总被引:1,自引:0,他引:1  
对美系短角肉种牛自1997年至今的饲养管理技术进行小结,供养殖业界同行参考。  相似文献   
194.
195.
极早熟、高产大豆新品种北豆24的选育及栽培技术   总被引:2,自引:0,他引:2  
介绍了北豆24的选育经过、主要特征特性及栽培技术。北豆24原代号北交04-912,是黑龙江省北安农场局科研所以克95-888为母本,北丰2号为父本进行有性杂交,系谱选育而成。2009年1月通过黑龙江省农作物品种审定委员会审定命名推广。  相似文献   
196.
Background: Atrial fibrillation (AF) with excessively high ventricular rates (VR) occurs in dogs with advanced heart disease. Rate control improves clinical signs in these patients. Optimal drug therapy and target VR remain poorly defined.
Hypothesis: Digoxin-diltiazem combination therapy reduces VR more than either drug alone in dogs with high VR AF.
Animals: Eighteen client-owned dogs (>15 kg) with advanced heart disease, AF, and average VR on 24-hour Holter > 140 beats per minute (bpm).
Methods: After baseline Holter recording, dogs were randomized to digoxin or diltiazem monotherapy, or combination therapy. Repeat Holter evaluation was obtained after 2 weeks; dogs were then crossed over to the other arm (monotherapy or combination therapy) for 2 weeks and a third Holter was acquired. Twenty-four hour average VR, absolute and relative VR changes from baseline, and percent time spent within prespecified VR ranges (>140, 100–140, and <100 bpm) were compared. Correlations between serum drug concentrations and VR were examined.
Results: Digoxin (median, 164 bpm) and diltiazem (median, 158 bpm) decreased VR from baseline (median, 194 bpm) less than the digoxin-diltiazem combination (median, 126 bpm) ( P < .008 for each comparison). With digoxin-diltiazem, VR remained <140 bpm for 85% of the recording period, but remained >140 bpm for 88% of the recording period with either monotherapy. Serum drug concentrations did not correlate with VR.
Conclusions and Clinical Importance: At the dosages used in this study, digoxin-diltiazem combination therapy provided a greater rate control than either drug alone in dogs with AF.  相似文献   
197.
为了给伪狂犬病病毒(PrV)UL24蛋白的细胞定位和功能研究提供参考依据,据GenBank公布的PrVUL24基因序列(登录号NC006151)设计1对引物,以质粒pUL24-GFP为模板,用PCR方法扩增出部分缺失的基因片段mUL24(modified UL24)。将mUL24片段定向克隆到原核表达载体pET-32a(+)中,构建融合表达载体pET-UL24。阳性质粒转化宿主菌E.coliBL21(DE3),经IPTG诱导,重组蛋白(His)6-UL24以包涵体的形式获得表达。用纯化后的pET-UL24融合蛋白免疫家兔,ELISA分析表明,在血清效价达到1∶2 560以上,Western-blot分析制备的抗体可以和pET-UL24表达产物发生反应,具有良好的免疫特异性。  相似文献   
198.
199.
为了降低输电网电能损耗,采用混和智能算法(粒子群算法与差异进化算法相结合)作为无功优化算法。该算法对不断变化的个体极值与整体极值进行研究,并且引入第三值分离相似性状,寻找最优补偿点的位置,从而有效补偿电能传输过程中的无功功率。通过IEEE系统例证分析,结果表明混合智能算法性能优于粒子群算法。说明混合智能算法对电能传输过程中所需无功功率有良好的补偿作用,对电网经济安全运行有良好的保障性。  相似文献   
200.
Radix scutellariae was used alone or in combination with other medicinal herbs in the treatment of type 2 diabetes mellitus in China. At present, the pharmacokinetics of baicalin in type 2 diabetic rats following oral administration of Radix scutellariae extract was investigated. The results showed that the pharmacokinetics (especially AUC) of baicalin in type 2 diabetic rats after oral administration of Radix scutellariae extract was remarkably different from that in normal rats. Then the mechanism which resulted in the increased AUC of baicalin in diabetic rats was investigated from system clearance and presystemic metabolism. And it was found that the increased AUC of baicalin in diabetic rats at least partly resulted from higher production of baicalein in the intestinal tract of type 2 diabetic rats. Moreover, the activity of β-glucuronidase in intestinal mucosa of type 2 diabetic rats was demonstrated to be higher than that in normal rats, which confirmed the results above. In conclusion, the pharmacokinetic behavior of baicalin was significantly altered in type 2 diabetic rats after orally administrated Radix scutellariae extract, which may partly result from the increased activity of intestinal β-glucuronidase under the pathological state of type 2 diabetes mellitus.  相似文献   
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