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41.
本课题合成四个氮基三乙酸单酰苯胺(IDA)类及其类似物肝胆显像螯合物。(1)用家兔做了肝胆显像扫描实验,其显像效果较好。(2)~(3)为未见报道的化合物。  相似文献   
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甲胎蛋白是一种癌胚相关蛋白,它在胎儿血清中含量每毫升数毫克之多,在正常人血清中低于25μg/ml,在原发性肝细胞癌者血清中甲胎蛋白的阳性率和滴度都很高,所以血清中甲胎蛋白的检测是诊断肝癌的特异指标。本方法采用双抗体夹心法原理,可定性及定量检测血清和血浆标本中甲胎蛋白含量,并配制AFP系列标准,为原发性肝癌的早期诊断及普查具有重要的临床意义。  相似文献   
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Honeybee (Apis mellifera) ingestion of toxic nectar plants can threaten their health and survival. However, little is known about how to help honeybees mitigate the effects of toxic nectar plant poisoning. We exposed honeybees to different concentrations of Bidens pilosa flower extracts and found that B. pilosa exposure significantly reduced honeybee survival in a dose-dependent manner. By measuring changes in detoxification and antioxidant enzymes and the gut microbiome, we found that superoxide dismutase, glutathione-S-transferase and carboxylesterase activities were significantly activated with increasing concentrations of B. pilosa and that different concentrations of B. pilosa exposure changed the structure of the honeybee gut microbiome, causing a significant reduction in the abundance of Bartonella (p < 0.001) and an increase in Lactobacillus. Importantly, by using Germ-Free bees, we found that colonization by the gut microbes Bartonella apis and Apilactobacillus kunkeei (original classification as Lactobacillus kunkeei) significantly increased the resistance of honeybees to B. pilosa and significantly upregulated bee-associated immune genes. These results suggest that honeybee detoxification systems possess a level of resistance to the toxic nectar plant B. pilosa and that the gut microbes B. apis and A. kunkeei may augment resistance to B. pilosa stress by improving host immunity.  相似文献   
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采用肾乳头暴露方法活体观察Sprague-Dawley大鼠肾髓质微循环。结果发现:正常成年大鼠肾乳头可暴露1.1±0.5mm; 乳头表面直血管数29.8±6.3;升、降支比例3.4:1。升支平均直径13.68±6.13μm,降支10.8±2.57μm。肾乳头连续暴露观察10h,其微循环未发生明显病理性改变。说明这一方法可以用于肾髓质微循环活体研究。  相似文献   
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Wang  Chunlei  Wei  Lijuan  Zhang  Jing  Hu  Dongliang  Gao  Rong  Liu  Yayu  Feng  Li  Gong  Wenting  Liao  Weibiao 《Journal of Plant Growth Regulation》2023,42(1):275-293

Salinity impairs plant growth and development, thereby leading to low yield and inferior quality of crops. Nitric oxide (NO) has emerged as an essential signaling molecule that is involved in regulating various physiological and biochemical processes in plants. In this study, tomato seedlings of Lycopersicum esculentum L. “Micro-Tom” treated with 150 mM sodium chloride (NaCl) conducted decreased plant height, total root length, and leaf area by 25.43%, 24.87%, and 33.67%, respectively. While nitrosoglutathione (GSNO) pretreatment ameliorated salt toxicity in a dose-dependent manner and 10 µM GSNO exhibited the most significant mitigation effect. It increased the plant height, total root length, and leaf area of tomato seedlings, which was 31.44%, 20.56%, and 51.21% higher than NaCl treatment alone, respectively. However, NO scavenger 2-(4-carboxyphenyl)-4, 4, 5, 5-tetramethylimidazoline-1-oxyl-3-oxide potassium (cPTIO) treatment reversed the positive effect of NO under salt stress, implying that NO is essential for the enhancement of salt tolerance. Additionally, NaCl?+?GSNO treatment effectively decreased O2? production and H2O2 content, increased the levels of soluble sugar, glycinebetaine, proline, and chlorophyll, and enhanced the activities of antioxidant enzymes and the content of antioxidants in tomato seedlings in comparison with NaCl treatment, whereas NaCl?+?cPTIO treatment significantly reversed the effect of NO under salt stress. Moreover, we found that GSNO treatment increased endogenous NO content, S-nitrosoglutathione reductase (GSNOR) activity, GSNOR expression and total S-nitrosylated level, and decreased S-nitrosothiol (SNO) content under salt stress, implicating that S-nitrosylation might be involved in NO-enhanced salt tolerance in tomatoes. Altogether, these results suggest that NO confers salt tolerance in tomato seedlings probably by the promotion of photosynthesis and osmotic balance, the enhancement of antioxidant capability and the increase of protein S-nitrosylation levels.

  相似文献   
48.
本文选用10个DMD基因内部和桥探针,对山东省9个地区的21个DMD/BMD家系的173名成员进行RFLP分析,其中可疑携带者55人,多数家系应用1-3个探针,有基因重组家庭选用4-5个探针,便可完成多态分析,RFLP分析可以确定85.45%的可疑携带者(≥95%可信限),即13人确定为携带者,30人排除携带者,另有4人风险大幅提高,通过这些探针的群体多态检测和不同家庭结构和类型的应用分析,我们提出了在中国人群中DMD/SMD基因诊断的基本程序。  相似文献   
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The gene (alyVI) encoding an alginate lyase of marine bacterium Vibrio sp. QY101, which was isolated from a decaying thallus of Laminaria, was cloned using a strategy of combined degenerate PCR and long range-inverse PCR (LR-IPCR), then sequenced and expressed in Escherichia coli. Gene alyVI was composed of a 1014 bp open reading frame (ORF) encoding 338 amino acid residues. The calculated molecular mass of alyVI product is 38.4 kDa, but a signal peptide is cleaved off, leaving a mature protein of 34 kDa. AlyVI was purified from culture supernatants to electrophoretic homogeneity using affinity chromatography. AlyVI was most active at pH 7.5 and 40 degrees C in the presence of 1 mM ZnCl2. A nine-amino-acid consensus region (YXRESLREM), which was only found in polyguluronate lyases, was also observed in the amino-terminal region of AlyVI. However, AlyVI could degrade both M block and G block. These results indicate that a novel alginate lyase-encoding gene has been cloned.  相似文献   
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