益肾降浊冲剂对慢性肾功能衰竭大鼠血浆自由基和心、小肠超微结构的影响研究

目的 :探讨益肾降浊冲剂治疗慢性肾功能衰竭 (CRF)的疗效和机理。方法 :采用 5 / 6肾切除大鼠CRF模型 ,随机分为模型组、大黄治疗组、益肾降浊冲剂大、小剂量治疗组 ,观察各组Scr、BUN、MDA、SOD ,以及心和小肠超微结构的改变。结果 :大黄组和益肾降浊冲剂大、小剂量组Scr、BUN、MDA、SOD均显著低于模型组(P <0 .0 1)。电镜观察心、小肠超微结构 ,模型组的病变最重 ,部分线粒体明显肿胀 ;益肾降浊冲剂组的病变最轻 ,线粒体形态无明显改变。结论 :推测本冲剂具有提高线粒体氧化磷酸化效率、减少和清除产生的自由基的药理作用 ,从而最大限度地保护线粒体和组织细胞 ,降低受毒素损害的程度。

3-素拟环导子的非幂零性

证明了 :设N是挠自由 3 -素拟环 ,d是N上的非零导子 ,若对于某a∈N ,d(a) ≠ 0 ,而使得[d(a) ,d(x) ]=0 , x∈N 。

自由基与人类衰老

自由基是人体代谢过程中产生的具有不配对电子的原子、原子团、分子或离子等。它性质活泼，具有强氧化性，正常情况下在机体内发挥重要的免疫作用，并能被机体存在的抗氧化系统所清除。随着外界环境的恶化，人体内自由基产生越来越多，其副作用也愈加明显，它可使脂褐素生成增加，线粒体DNA突变、蛋白质合成减少等作用加速衰老。

Characteristics and fate behavior of environmentally persistent free radicals in atmospheric particulate matter

Background,aim,and scope Environmentally persistent free radicals(EPFRs)have received significant attention due to their longer lifetime and stable existence in various environments.The strong environmental migration ability of particulate matter allows EPFRs to migrate over long-distance transport,thereby impacting the quality of the local atmospheric environment.Additionally,EPFRs can also adhere to atmospheric particles and interact with typical gaseous pollutants to affect atmospheric chemical reactions.EPFRs can produce some reactive organic species,promoting oxidative stress in the human body,damaging biological macromolecules and ultimately affecting the organism health.EPFRs are considered as a novel type of pollutant that affects human health.Despite their significance,there are few literatures available on the characteristics and fate behaviors of EPFRs up to date.Therefore,supplemental reviews are crucial for providing comprehensive understanding of EPFRs.Materials and methods This review summarizes the characteristics of EPFRs in particulate matter,outlines the generation mechanism and influencing factors of EPFRs,and the impacts of EPFRs on environmental quality and organism health.Results The content of EPFRs in particulate matter ranges from 1017 to 1020 spins∙g−1.Due to the strong mobility of atmospheric particulate matter,the long-term exposure to high levels of EPFRs may aggravate the impact of particulate matter on human health.The interaction between EPFRs and typical gaseous pollutants can alter their fate and influence atmospheric chemical reactions.EPFRs are mainly produced by transition metal elements and substituted aromatic hydrocarbons through electron transfer.Additionally,the chemical bond rupture of organic substances through heat treatment or ultraviolet radiation can also produce EPFRs,and heterogeneous reactions are capable producing them as well.The production of EPFRs is not only influenced by transition metal elements and precursors,but also by various environmental factors such as oxygen,temperature,light radiation,and relative humidity.Discussion EPFRs in atmospheric particulates matters are usually rich in fine particulates with obvious seasonal and regional variations.They can easily enter the human respiratory tract and lungs with inhalable particulates,thereby increasing the risk of exposure.Additionally,EPFRs in atmospheric particulates can interact with some typical gaseous pollutants,impacting the life and fate of EPFRs in the atmosphere,and alter atmospheric chemical reactions.Traditionally,EPFRs are generated by transition metal elements and substituted aromatic hydrocarbons undergoing electron transfer in the post-flame and cool-zone regions of combustion systems and other thermal processes to remove HCl,H_(2)O or CO groups,ultimately produce semiquinones,phenoxyls,and cyclopentadienyls.Recent studies have indicated that EPFRs can also be generated under the conditions of without transition metal elemental.Organics can also produce EPFRs through chemical bond rupture during heat treatment or light radiation conditions,as well as through some heterogeneous reactions and photochemical secondary generation of EPFRs.The presence or absence of oxygen has different effects on the type and yield of EPFRs.The concentration,type,and crystal type of transition metal elements will affect the type,content,and atmospheric lifetime of EPFRs.It is generally believed that the impact of transition metal element types on EPFRs is related to the oxidation-reduction potential.The combustion temperature or heat treatment process significantly affects the type and amount of EPFRs.Factors such as precursor loading content,pH conditions,light radiation and relative humidity also influence the generation of EPFRs.EPFRs can interact with pollutants in the environment during their migration and transformation process in environmental medium.This process accelerates the degradation of pollutants and plays a crucial role in the migration and transformation of organic pollutants in environmental media.The reaction process of EPFRs may lead to the production of reactive oxygen species(ROS)such as∙OH,which can induce oxidative stress,inflammation and immune response to biological lung cells and tissues,leading to chronic respiratory and cardiopulmonary dysfunction,cardiovascular damage and neurotoxic effects,ultimately impacting the health of organisms.Conclusions The interaction mechanism between EPFRs in particulate matter and gaseous pollutants remains unclear.Furthermore,research on the generation mechanism of EPFRs without the participation of transition metals is not comprehensive,and the detection of EPFRs is limited to simple qualitative categories and lack accurate qualitative analysis.Recommendations and perspectives Further research should be conducted on the generation mechanism,measurement techniques,migration pathways,and transformation process of EPFRs.It is also important to explore the interaction between EPFRs in atmospheric particulate matter and typical gaseous pollutants.

Factors Influencing the Effects of Theabrownin in Pu-erh Tea on Scavenging DPPH Radicals

[Objective] This study aimed to explore factors influencing the effects of theabrownin in Pu-erh tea on scavenging DPPH radicals. [Method] Taking Pu-erh tea as main research object, theabrownin in Pu-erh tea from tea piles with different times of mixture, stored for different years and processed by both the old and new techniques were extracted and isolated. And DPPH method was used to study the effects of theabrownin solution and tea liquor on scavenging radicals and their antioxidant activity. [Result] The result showed that the theabrownin content in Pu-erh tea from tea piles with one to four times of mixture revealed a first declining and subsequently rising trend. Under different pH conditions, the rates of DPPH radical scavenging of 1 mg/ml theabrownin solution made from tea piles with different times of mixture decreased gradually with the increase of pH, and all the rates were lower than that of the control vitamin C solution; the rates of DPPH radical scavenging of theabrownin from tea samples stored for different years and produced by different techniques dropped slowly within pH range 3.0-6.0; when pH was higher than 6.0, the rates of DPPH radical scavenging of theabrownin from tea samples produced by both new and traditional techniques in 2001 declined obviously, while the declining trend was not obvious in either the black tea or the Pu-erh tea produced by new technique in 2005. Under different theabrownin concentrations, the rates of DPPH radical scavenging of theabrownin solution made from tea piles with different times of mixture ascended as the concentration increased and the highest rate occurred in tea pile with four times of mixture, reaching up to 46.56%±0.88%; for tea samples stored for different years and produced by different techniques, the rates of DPPH radical scavenging of theabrownin rose gradually with the increase of the theabrownin concentration; the rate of radical scavenging of theabrownin in the black tea ascended obviously and that in Pu-erh tea was decreasing within the concentration range of 0.04 -0.06 mg/ml. At pH6.0, the DPPH radical scavenging ability of theabrownin in 0.1 mg/ml theabrownin solution and tea liquor containing 0.1mg/ml theabrownin from tea piles with different times of mixture ascended with the time of mixture; solution made from tea samples produced by different techniques in different years, the DPPH radical scavenging ability of theabrownin solution and tea liquor followed： Pu-erh tea produced by the new technique in 2001 ﹥ Pu-erh tea produced by the old technique in 2001﹥ Pu-erh tea produced by the new technique in 2005. And the DPPH radical scavenging ability of theabrownin in tea liquor containing 0.1 mg/ml theabrownin was higher than that in 0.1 mg/ml theabrownin Solution made from tea samples either with different times of mixture or produced by different techniques in different years. The above results indicated that many factor influenced the effects of theabrownin on eliminating DPPH radicals, including the time of fermentation, fermentation technique, years of storage, concentration and pH all had great influence on the effects of theabrownin on eliminating radicals. To ensure a good effect on scavenging radicals, it is better to prepare theabrownin at pH6.0 with concentration between 0.08 and 0.1 mg/ml for drinking. [Conclusion] Results of this study provide a basis for developing functional products of theabrownin from Pu-erh tea in the future.

Antioxidant phenanthrenes and lignans from Dendrobium nobile

To study the antioxidant constituents from the stems of Dendrobium nobile, and to discuss theft structure-activity relationship. Compounds were isolated from a 60% ethanolic extract by various chromatographic techniques and were identified by spectral analysis. The antioxidant activities of compounds were evaluated by DPPH free radical scavenging assay. Five phenanthrenes and four lignans were obtained from the active fractions ofD. nobile. Their structures were identified as fimbriatone （1）, confusarin （2）, flavanthrinin （3）, 2,5-dihydroxy-4,9-dimethoxyphenanthrene （4）, 3,7-dihydroxy-2,4-dimethoxyphenanthrene （5）, syringaresinol （6）, pinoresinol （7）, medioresinol （8） and lirioresinol-A （9）, respectively. Compounds 2 and 6 exhibited more potent DPPH scavenging activities than vitamin C. All the above compounds were reported from this plant for the first time, and compounds 3, 4 and 9 were reported for the first time from the genus of Dendrobiurn. For all phenanthrenes and lignans, an electron-donating methoxyl group in the ortho position to the phenolic hydroxyl group exhibits enhanced antioxidant activities.

Extraction of Pumpkin Polysaccharide by Complex Enzyme Method and Its Antioxidant Research

[Objective] This paper aims to study a new method of extracting pumpkin polysaccharide from pumpkin. Single factor experiments were conducted to examine the effects of extracting time,temperature,the solid-liquid ratio and pH value on the extraction yield of polysaccharide from pumpkin. [Method] The best enzyme ratio and extraction conditions for complex enzymes extraction were determined through orthogonal tests. Scavenging ·OH and O-2 activities of pumpkin polysaccharides were also investigated by salicylic acid and improved self-oxidation of o-pheno methods respectively. [Results] The results showed that the biggest extraction yield of polysaccharide from pumpkin can be got when adding 1% cellulose enzyme,1.5% pectinase,1.0% papain and Na2HPO4-citric acid buffer solution (pH was 4.6),and oscillating for 30 min under water at 40 ℃ with the solid-liquid ratio of 1:30. In addition,pumpkin polysaccharides had a strong activity of eliminating ·OH,but very weak activity to scavenge O-2. [Conclusion] This study provided basic data for research and application of Pumpkin polysaccharide.

试论俄语零动词述体句的语义

在现代俄语中广泛地应用着零位动词述体句(或称无动词句)。很多语言学家认为,这种类型的句子在语法结构和语义结构上都是完整的。这种结构句都被认为是完全句。充当零位动词述体句中的从属词构成了该结构句中不可缺少的结构要素,它们是判断零位动词述体句语义的主要依据。

儿化词合音新义产生的认知机制

儿化是汉语常见的语言现象,本文运用认知语法的象征图式理论,探究儿化词能够改变词义产生新词的原因以及儿化合音背后的认知机制。研究表明,儿化词的结构形式为“自由语素+黏着语素”,依据词性不同儿化词可以分为“名词性成分+儿”“动词性成分+儿”等六类,其中又可以根据是否产生新的词汇意义分为单纯儿化和非单纯儿化,单纯儿化不会改变词义,非单纯儿化分别利用隐喻和转喻机制产生新词。儿化词语义极的自由/黏着结构同时也反映在语音极层面,在音节压制的作用下,“er”发生合音,由独立的音节变为黏着成分“-r”。

Recovery of Astaxanthin from Discharged Wastewater During the Production of Chitin

In this paper, studies were carried out to extract astaxanthin from discharged wastewater during the production of chitin and to reveal the scavenging effect of the obtained pigment on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical. Different ratios of dichloromethane/methanol (V/V) were used to extract astaxanthin. When the ratio of dichloromethane/methanol was 2:8 and the ratio between the mixed organic solvent (dichloromethane/methanol, 2:8, V/V) and wastewater was 1:1, the highest yield of pigment was obtained (8.4 mg/ 50 mL). The concentration of free astaxanthin in the obtained pigment analyzed by HPLC was 30.02%. The obtained pigment possessed strong scavenging ability on DPPH radical and IC50 was 0.84mg/ml.

Inhibitory effects of grape procyanidins on free radical-induced cell damage in rat hepatocytes in vitro

AIM： To study the protective effect of grape procyanidins on oxidative injury induced by ethanol and carbon tetrachloride in rat hepatocytes. METHODS： Normal rat hepatocytes as well as cells damaged by ethanol or carbon tetrachloride were incubated with different doses of grape procyanidins for 24 h. Cell proliferation, apoptosis and TNFα mRNA expression were subsequently determined using MTT assay, cell death ELISA and in situ hybridization. RESULTS： Proliferative levels of the control cells from ethanol and CCh injury groups significantly decreased while apoptosis and TNFα mRNA expression significantly increased compared to the normal control and grape procyanidins co-treatment groups （0.455 ± 0.051 vs 0.318 ±0.045, P 〈 0.05）. In comparison with the normal control, 50 and 100 mg/L grape procyanidins significantly stimulated cell growth, with a better effect observed with 100 mg/L grape procyanidins. CONCLUSION： Grape procyanidins inhibit the hepatocyte damage induced by ethanol and carbon tetrachloride, and stimulate normal hepatocyte proliferation.

Significant role of carbonate radicals in tetracycline hydrochloride degradation based on solar light-driven TiO2-seashell composites:Removal and transformation pathways

TiO2-seashell composites prepared via a sol-gel method were used to generate carbonate radicals(·CO3–) under solar light irradiation. ·CO3–, a selective radical, was employed to degrade the target tetracycline hydrochloride contaminant. A series of characterizations was carried out to study the structure and composition of the synthesized TiO2-seashell composite. This material exhibits excellent solar light-driven photochemical activity in the decomposition of tetracycline hydrochloride. The possible pathway and mechanism for the photodegradation process were proposed on the basis of high-resolution electrospray ionization time-of-flight mass spectrometry experiments. Finally, we investigated the reusability of the TiO2-seashell composite. This study is expected to provide a new facile pathway for the application of ·CO3– radicals to degrade special organic pollutants in water.

A new 3-D element formulation on displacement of steel-concrete composite box beam

Slip of a composite box beam may reduce its stiffness, enlarge its deformation and affect its performance. In this work, the governing differential equations and boundary conditions of composite box beams were established. Analytic solutions of combined differential equations were also established. Partial degree of freedom was adopted to establish a new FEA element of three-dimensional beam, taking into account the slip effect. Slip and its first-order derivative were introduced into the nodes of composite box beams as generalized degree of freedom. Stiffness matrix and load array of beam elements were established. A three-dimensional nonlinear calculation program was worked out. The results show that the element is reliable and easy to divide and is suitable for special nonlinear analysis of large-span composite box beams.

Freedoms and Restrictions of Translator＇s Subjectivity in Literary Translation

With the translation studies leaning to target-language, the translator＇s subjectivity has been paid more and more attention by translation scholars. It is noticed gradually that translation is actually a dynamic and complex process, during which the translator, acting as a reader of the source text and also a writer of the target text, will unavoidably add something subjective in his or her translation. Since literary translation is interwoven with more cultural and social elements, the translator has to make a choice between loyalty and violation, getting freedom and being restricted when he or she confronts with all the clashes and conflicts between the source language culture and the target language culture.

再论素组:语言分析的新概念

一、素组是客观存在的一级语言单位 关于“素组”这个概念的提出理由,笔者已经在《论素组》 (《松辽学刊》,1992年2期)一文中作了阐述。我们所说的素组是指大于语素的一种构词单位。分析一个多语素构成的合成词,就自然会得出素组这种语言单位。比如,“青春宝”(药名)是由“青春”和“宝”两个语言单位直接构成的,“一洗黑”(化妆品)是由“一洗”和“黑”两个语言单位构成的。在这两个词中,作为构词成分的“宝”和“黑”,我们都称作语素,而同样作为构词成分的“青春”和“一洗”,能否也称之为语素呢?显然不可以。因为语素是最小的语音语义结合体。如果我们把“青春”、“一洗”之类单位也叫作语素,那么,原来为语言学界所普遍承认的语素定义就不能不加以更改了。有人试图把这种语言单位叫作“合成词(语)素”,那也仍然无法回避上面提到的矛盾。既然是“合成”,当然就不可能是“最小”了。可见,这类由语素合成的语言单位的确不能再称作“语素”,即便是加上某些修饰语也还是不可以。也有人另僻蹊径,提出词素、语素分工的设想。即语素的含义基本不变,依然是最小的音义结合体;而词素则被赋予新的含义,指的是词的构造成素,是词或词干的直接组成成分。这样,“

On the Diophantine Equation y^2= px（x^2＋ 2）

For any fixed odd prime p, let N（p） denote the number of positive integer solutions （x, y） of the equation y^2 = px（x^2 ＋ 2）. In this paper, using some properties of binary quartic Diophantine equations, we prove that ifp ≡ 5 or 7（mod 8）, then N（p） = 0; ifp ≡ 1（mod 8）, then N（p） 〈 1; if p〉 3 andp ≡ 3（rood 8）, then N（p） ≤ 2.

Stability of proteins with multi-state unfolding behavior

A new model used to calculate the free energy change of protein unfolding is presented. In this model, proteins are considered to be composed of structural elements. The unfolding of a structural element obeys a two-state mechanism and the free energy change of the element can be obtained by a linear extrapolation method. If a protein consists of the same structural elements, its unfolding will displays a two-state process, and only the average structural element free energy change 〈△G0 element（H2O）〉 can be measured. If protein consists of completely different structural elements, its unfolding will show a multi-state behavior. When a protein consists of n structural elements its unfolding will shows a （n＋1）-state behavior. A least-squares fitting can be used to analyze the contribution of each structural element to the protein and the free energy change of each structural element can be obtained by using linear extrapolation to zero denaturant concentration, not to the start of each transition. The measured △Gn protein（H2O） is the sum of the free energy change for each structural element. Using this new model, we can not only analyze the stability of various proteins with similar structure and similar molecular weight, which undergo multi-state unfolding processes, but also compare the stability of proteins with different structures and molecular weights using the average structural element free energy change 〈△G0 element（H2O）〉. Although this method cannot completely provide the exact free energy of proteins, it is better than current methods.

Pulse radiolysis study on gatifloxacin——A fluoroquinolone antibiotic

The reactions between gatifloxacin(GFX) and various one-electron oxidants,such as ˙OH,N3˙,Br2˙ˉ,and SO4˙ˉ,have been studied by pulse radiolysis techniques.The GFX radical anion formed in the reaction of GFX with eaqˉ could either be protonated or deprotonated,and the absorption of GFX radical anion was located at 390 nm.The transient species produced by the reaction of GFX with ˙OH radical shows a broad band in the 380?600 nm region with a shoulder,while the oxidation by N3˙,SO4˙ˉ,and Br2˙ˉ results in an absorption band with λmax = 370 nm.At neutral condition(pH 7),the rate constants of GFX reacting with ˙OH,N3˙,Br2˙ˉ,SO4˙ˉ and eaqˉ are estimated to be 1.0 × 1010,3.1 × 109,2.8 × 109,3.0 × 109,and 1.8 × 1010 dm3 mol?1 s?1,respectively.From the pH dependence on the formation of electron adducts and on the rate constant of GFX with eaqˉ,the pKa of GFX radical anion is estimated to be 5.5 and 9.3.

Isotope effect of the phonons mean free path in graphene by micro-Raman measurement

The isotope labeled graphene was synthesized in the concentration of 13 C carbon atom in 1%, 25%, 50%, 75% and 99%. The isotope effect on the phonon behavior in graphene was investigated based on the micro-Raman analysis of 13 C isotope labeled graphene samples. We found that the phonon scattering is affected by the isotopic carbon atom as a point defect. Based on the experiment results, the Klemens-Callaway model and uncertainty principle were used to obtain the mean free path of the G and D phonons. The results agree with the thermal conductivity measurement by non-contact optical method and with other theoretical calculations.