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171.
八角枫挥发油化学成分研究   总被引:1,自引:0,他引:1  
八角栎是八角枫科八角枫属药用植物,分布较广。用气相色谱/质谱/计算机联用技术(GC/MS/DS)分析了水蒸气蒸馏得到的八角枫挥发油,鉴定出59种化学成分,其主要成分为:1,8-桉叶素(43.325%)、β-侧然(10.713%)、丁香酚甲醚(7.088)、α-松油醇(7.017%)、α-蒎烯(5.830%)等5种化合物。被鉴定的59种成分,共占挥发油总量的97.04%。  相似文献   
172.
Aim:  The study investigated the potential of using Bacillus subtilis MA139 in combination with Lactobacillus fermentum and Saccharomyces cerevisae to produce solid-state fermentation feed.
Methods and Results:  In a pure fermentation, B. subtilis MA139 was able to grow and synthesize antimicrobial substances at temperatures from 25 to 37°C and at a pH from 5·0 to 9·0. Subsequently, B. subtilis MA139, Lact. fermentum and S. cerevisae were used as starter strains co-inoculated in unsterilized substrate (feed-grade soybean meal and wheat bran). Following 10 days of fermentation in a newly developed plastic bag equipped with a one-way valve, lactic acid bacteria and Bacillus became the predominant strains while S. cerevisae cells decreased slightly. Enterobacteriaceae ( Escherichia coli K88 and Salmonella typhimurium ) were not detected.
Conclusions:  Use of B. subtilis MA139 as a starter strain co-inoculated with S. cerevisae and Lact. fermentum successfully controlled the growth of enterobacteriaceae.
Significance and Impact of the Study:  This study provided a facile and low-cost way to produce solid-state fermentation feed.  相似文献   
173.
目的探讨64层螺旋CT血管造影在胸部大血管成像的临床应用价值。方法回顾分析了112例患者行64层螺旋CT胸部大血管造影资料,以临床手术或随访结果为金标准,进行图像分析。结果CT能够显示主动脉、肺动静脉的结构,可以诊断主动脉夹层、主动脉瘤、肺栓塞、先天性心脏病等多种大血管病变,诊断准确率100%。结论64层CT血管造影扫描速度快、安全、准确,是胸部大血管病变的首选方法。  相似文献   
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The inducible form of heme oxygenase (HO-1) is increased during oxidative injury and HO-1 is believed to be an important defense mechanism against such injury. Arachidonic acid (AA) and l-buthionine-(S,R)-sulfoximine (BSO), which lowers GSH levels, cause cytochrome P450 2E1 (CYP2E1)-dependent oxidative injuries in HepG2 cells (E47 cells). Treatment of E47 cells with 50 microM AA or 100 microM BSO for 48 h was recently shown to increase HO-1 mRNA, protein, and activity. The possible functional significance of this increase in protecting against CYP2E1-dependent toxicity was evaluated in the current study. The treatment with AA and BSO caused loss of cell viability (40 and 50%, respectively) in E47 cells. Chromium mesoporphyrin (CrMP), an inhibitor of HO activity, significantly potentiated this cytotoxicity. ROS production, lipid peroxidation, and the decline in mitochondrial membrane potential produced by AA and BSO were also enhanced in the presence of CrMP in E47 cells. Infection with an adenovirus expressing rat HO-1 protected E47 cells from AA toxicity, increasing cell viability and reducing LDH release. HO catalyzes formation of CO, bilirubin, and iron from the oxidation of heme. Bilirubin was not protective whereas iron catalyzed the AA toxicity. The carbon monoxide (CO) scavenger hemoglobin enhanced AA toxicity in E47 cells analogous to CrMP, whereas exposure to exogenous CO partially reduced AA toxicity and the enhanced AA toxicity by CrMP. Addition of exogenous CO to the cells inhibited CYP2E1 catalytic activity, as did overexpression of the rat HO-1 adenovirus. These results suggest that induction of HO-1 protects against CYP2E1-dependent toxicity and this protection may be mediated in part via production of CO and CO inhibition of CYP2E1 activity.  相似文献   
177.
Severe acute respiratory syndrome (SARS) brought aglobal outbreak in spring of 2003 [1–3], and more andmore attention has been paid on it when a new caseresurfaced in Singapore last September [4]. By the endof May in 2003, WHO reported a cumulative total of 8202infected cases with 725 deaths from 28 countries.Because of the high transmission and morality rate ofSARS, scientists in many countries have made theirefforts in studying SARS coronavirus (SARS-CoV)[5, 6]. Several genomes of…  相似文献   
178.
Correlation between spike trains or neurons sometimes indicates certain neural coding rules in the visual system. In this paper, the relationship between spike timing correlation and pattern correlation is discussed, and their ability to represent stimulus features is compared to examine their coding strategies not only in individual neurons but also in population. Two kinds of stimuli, natural movies and checkerboard, are used to arouse firing activities in chicken retinal ganglion cells. The spike timing correlation and pattern correlation are calculated by cross-correlation function and Lempel–Ziv distance respectively. According to the correlation values, it is demonstrated that spike trains with similar spike patterns are not necessarily concerted in firing time. Moreover, spike pattern correlation values between individual neurons’ responses reflect the difference of natural movies and checkerboard; neurons cooperate with each other with higher pattern correlation values which represent spatiotemporal correlations during response to natural movies. Spike timing does not reflect stimulus features as obvious as spike patterns, caused by their particular coding properties or physiological foundation. As a result, separating the pattern correlation out of traditional timing correlation concept uncover additional insight in neural coding.  相似文献   
179.
Benign prostatic hyperplasia (BPH) occurs most commonly among older men, often accompanied by chronic tissue inflammation. Although its aetiology remains unclear, autoimmune dysregulation may contribute to BPH. Regulatory T cells (Tregs) prevent autoimmune responses and maintain immune homeostasis. In this study, we aimed to investigate Tregs frequency, phenotype, and function in BPH patients and to evaluate adoptive transfer Tregs for immunotherapy in mice with BPH via CD39. Prostate specimens and peripheral blood from BPH patients were used to investigate Treg subsets, phenotype and Treg‐associated cytokine production. Sorted CD39+/? Tregs from healthy mice were adoptively transferred into mice before or after testosterone propionate administration. The Tregs percentage in peripheral blood from BPH patients was attenuated, exhibiting low Foxp3 and CD39 expression with low levels of serum IL‐10, IL‐35 and TGF‐β. Immunohistochemistry revealed Foxp3+ cells were significantly diminished in BPH prostate with severe inflammatory. Although the Tregs subset was comprised of more effector/memory Tregs, CD39 was still down‐regulated on effector/memory Tregs in BPH patients. Before or after testosterone propionate administration, no alterations of BPH symptoms were observed due to CD39‐ Tregs in mice, however, CD39+Tregs existed more potency than Tregs to regulate prostatic hyperplasia and inhibit inflammation by decreasing IL‐1β and PSA secretion, and increasing IL‐10 and TGF‐β secretion. Furthermore, adoptive transfer with functional Tregs not only improved prostate hyperplasia but also regulated muscle cell proliferation in bladder. Adoptive transfer with Tregs may provide a novel method for the prevention and treatment of BPH clinically.  相似文献   
180.
Molecular Breeding - Lack of seed dormancy, a major cause of pre-harvest sprouting in rice and other cereal crops, causes significant reductions in grain yield and quality. Weedy rice is often...  相似文献   
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