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1.
西北产6种药用柴胡营养器官的比较解剖学研究   总被引:6,自引:0,他引:6  
柴胡是伞形科柴胡属植物,据报道,全世界有150种左右,主要分布在北半球及亚热带地区,初步统计我国有30余种。据我们在西北五省调查,药用种类有21种之多,药用主流种类有柴胡Bupleurum chinesis DC.、狭叶柴胡B. scorzonerifolium Willd.、银州柴胡B. yinchowense Shan et Y. Li、小叶黑柴胡B. smithii Wolff. var. parvi-  相似文献   
2.
脐血浆治疗大鼠实验性肝衰竭及其机制的研究   总被引:2,自引:0,他引:2  
本文采用脐血浆治疗实验性肝衰竭大鼠模型,并与成人血浆的疗效进行了比较。结果表明,脐血浆降低大鼠死亡率、血谷丙转氨酶水平,总胆红素浓度及使甲胎蛋白水平升高均明显高于成人血浆的作用(P<0.05).肝脏病理组织学也显示脐血浆具有减轻病理损害和较快修复坏死组织的作用。提示脐血浆中含有促进肝细胞再生的因子,具有显著提高实验性大鼠肝衰竭的存活率。  相似文献   
3.
The ability of 2-n-propyl-4-pentenoic acid (Δ4-VPA) and 2-n-propyl-2(E)-pentenoic acid ([E]-Δ2-VPA), two unsaturated metabolites of valproic acid (VPA), to form reactive intermediates, deplete hepatic glutathione (GSH) and cause accumulation of liver triglycerides was investigated in the rat. With the aid of ionspray liquid chromatography-tandem mass spectrometry (LC-MS/MS), three GSH adducts were detected in the bile of Δ4-VPA-treated animals and were identified as 4-hydroxy-5-glutathion-S-yl-VPA-γ-lactone, 5-glutathion-S-yl-(E)-Δ3-VPA and 3-oxo-5-glutathion-S-yl-VPA. A fourth conjugate was identified tentatively as 4-glutathion-S-yl-5-hydroxy-VPA. Quantitative analysis of the corresponding N-acetylcysteine (NAC) conjugates in urine indicated that metabolism of Δ4-VPA via the GSH-dependent pathways accounted for approximately 20% of an acute dose (100 mg kg−1 i.p.). In contrast, when rats were given an equivalent dose of (E)-Δ2-VPA, only one GSH adduct (5-glutathion-S-yl-(E)-Δ3-VPA) was detected at low concentrations in bile. In vitro experiments with rat liver mitochondria demonstrated that Δ4-VPA undergoes coenzyme A- and ATP-dependent metabolic activation in this organelle via the β-oxidation pathway to intermediates which bind covalently to proteins. When liver homogenates and hepatic mitochondria from rats injected with Δ4-VPA, (E)-Δ2-VPA or VPA were analyzed for GSH content, it was found that only Δ4-VPA depleted GSH pools significantly. Treatment of rats with Δ4-VPA and (to a lesser extent) VPA led to an accumulation of liver triglycerides, whereas (E)-Δ2-VPA had no measurable effect. It is concluded that Δ4-VPA undergoes metabolic activation by both microsomal cytochrome P-450-dependent and mitochondrial coenzyme A-dependent processes, and that the resulting electrophilic intermediates, which are trapped in part by GSH, may mediate the hepatotoxic effects of this compound. In contrast, (E)-Δ2-VPA is not transformed to any appreciable extent to reactive metabolites, which thus accounts for the apparent lack of hepatotoxicity of this positional isomer in the rat.  相似文献   
4.
利用停留仪快速反应动力学方法和自旋捕集ESR技术监测高铁离子自由基和自旋捕捉剂POBN的反应,发现高铁离子自由基本身不被自旋捕捉剂POBN捕捉,但是POBN可以捕捉到停流仪第三相中的OH,可能来自剩余的Fenton试剂或高铁离子自由基的衰变。以含两个双键的不饱和脂肪酸-亚油酸(LH)作为模型化合物,测定高铁离子自由基与亚油酸分子的反应速率。ESR结果表明,高铁离子自由基可能在一定程度上启动了亚油酸体系的脂质过氧化。  相似文献   
5.
中药红毛五加(Acanthopanax giraldii Harms)属五加科植物,本文通过细胞化学定性、定位、定量研究探讨红毛五加多糖(AGPS)对腹腔巨噬细胞的作用及机理。实验证明AGPS能使巨噬细胞数量明显增多,细胞体积增大,伪足增多,吞噬能力增强,细胞内醣类、酸性磷酸酶、三磷酸腺昔酶、酸性酯酶和琥珀酸脱氢酶活性显著增强。用显微分光光度计对上述单个细胞的化学成分进行定量测定。实验组和对照组结果有显著差异。提示红毛五加的扶正固本作用十分明显,本研究为AGPS的应用和作用机理提供了一定的实验依据。  相似文献   
6.
7.
Zhang  Lixia  Chang  Qingshan  Hou  Xiaogai  Wang  Jianzhang  Chen  Sudan  Zhang  Qiaoming  Wang  Zi  Yin  Yan  Liu  Jianke 《Journal of Plant Growth Regulation》2023,42(3):1631-1646

In this study, two herbaceous peony cultivars with different heat tolerances (‘Fenyunu’ FYN low sensitivity and ‘Qiaoling’ QL high sensitivity) were used as research materials. An integrated view of the factors underlying the decrease in photosynthetic rate under high-temperature (HT) stress was provided by analyzing the biochemical parameters, chloroplast ultrastructure, gas-exchange parameters, chlorophyll fluorescence, and modulated 820 nm reflection of herbaceous peony leaves. The results showed that hydrogen peroxide, superoxide anion, malondialdehyde, and electrical conductivity increased significantly, while the photosynthetic pigments content and photosynthetic capacity decreased significantly in QL than in FYN under HT. The contents of soluble sugars and proline increased greatly in FYN than in QL, while the activity of SOD decreased markedly in QL than in FYN after HT. Compared with FYN, the ultrastructure of QL was more seriously disrupted under HT. Chlorophyll fluorescence analysis showed that HT changed the shapes of OJIP curve, resulting in the increase of K phase and J phase. The PSII acceptor side was more damaged than the donor side, and the electron transfer was seriously blocked. The energy flow in the process of light energy absorption, capture, and electron transfer were significantly changed after HT stress. Meanwhile, PSI was also significantly inhibited, and the coordination of both photosystems decreased. The variation of these parameters in FYN was less than that in QL. These results suggested that FYN featured a more heat-tolerance ability as evidenced by the good performances on the antioxidant system, osmoregulatory capacity, and the thermostability of membranes and photosystems.

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8.
本文用抗氟化物酸性磷酸酶(FRAP)法和显微测量,对大鼠正中神经一级传入纤维在脊髓胶状质(SG)的定位投射进行了定量分析.大鼠正中神经向SG的纵向投射主要为C_5~T_1.C_5~T_1各节段SG水平向眉毛状反应带所测均值(mm)分别为0.888、0.935、0.957、0.905和 0.776,而正中神经向C_5~T_1各节段SG水平向投射所测均值(mm)分别在0~0.204、0~0.303、0~0.409、0~0.432和0~0.336的范围,这显示了正中神经投射区均位于SG的内侧带和部分中间带.  相似文献   
9.
Endophytic fungi can be beneficial to plant growth. However, the molecular mechanisms underlying colonization of Acremonium spp. remain unclear.In this study, a novel endophytic Acremonium strain was isolated from the buds of Panax notoginseng and named Acremonium sp. D212. The Acremonium sp. D212 could colonize the roots of P. notoginseng,enhance the resistance of P. notoginseng to root rot disease, and promote root growth and saponin biosynthesis in P. notoginseng. Acremonium sp. D212 could secrete indole-3-acetic acid(IAA) and jasmonic acid(JA), and inoculation with the fungus increased the endogenous levels of IAA and JA in P. notoginseng. Colonization of the Acremonium sp. D212 in the roots of the rice line Nipponbare was dependent on the concentration of methyl jasmonate(Me JA)(2–15 μmol/L) and 1-naphthalenacetic acid(NAA)(10–20 μmol/L). Moreover, the roots of the JA signaling-defective coi1-18 mutant were colonized by Acremonium sp. D212 to a lesser degree than those of the wild-type Nipponbare and mi R393 boverexpressing lines, and the colonization was rescued by Me JA but not by NAA. It suggests that the cross-talk between JA signaling and the auxin biosynthetic pathway plays a crucial role in the colonization of Acremonium sp. D212 in host plants.  相似文献   
10.
Euphorbia factor L3, a lathyrane diterpenoid extracted from Euphorbia lathyris, was found to display good anti‐inflammatory activity with very low cytotoxicity. To find more potent anti‐inflammatory drugs, two series of Euphorbia factor L3 derivatives with fatty and aromatic acids were designed and synthesized. Among them, lathyrane derivative 5n exhibited most potent inhibition on LPS‐induced NO production in RAW264.7 cells with no obvious cytotoxicity. To determine the key characteristics of Euphorbia factor L3 derivatives that contribute to anti‐inflammatory activity, we conducted a structure‐activity relationship study of these compounds.  相似文献   
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