新型胆碱酯酶抑制剂对AD大鼠空间记忆及海马结构胆碱能纤维的影响

目的探讨新型胆碱酯酶抑制剂(NAI)及水迷宫训练对AD大鼠海马结构胆碱能纤维的影响。方法用36只Wistar♂大鼠制作AD动物模型,随机分成3组:NAI组、石杉碱甲组(Hup组)、单纯损伤组(SO组)。水迷宫训练后,采用组织化学方法测定海马结构胆碱能纤维密度。结果①定位航行实验中,NAI组逃避潜伏期较SO组显著缩短(P<0.01)。②空间探索实验中,NAI组跨越各象限平台相应位置次数占总次数百分率较SO组明显增高(P<0.01)。③组化结果显示:NAI组海马结构胆碱能纤维密度较SO组明显增加(P<0.05)。尽管NAI组胆碱能纤维密度高于Hup组,但无统计学意义。结论经NAI治疗及水迷宫行为训练后的AD大鼠,海马结构内胆碱能纤维密度明显增加,提示NAI及水迷宫训练联合作用可促进AD大鼠海马结构胆碱能纤维重建。     

湿法磷酸生产中泥浆的产生及处理方法

简述红磷公司 3套磷酸装置生产中泥浆的产生过程及泥浆的组成 ;探讨泥浆处理的方法 ,并提出了稀磷酸、浓磷酸两步沉降法的可行性     

治疗骨质疏松症的药物概述

骨质疏松是一种以骨密度和骨质量减低为特征的导致骨质松软、骨折危险性增加的疾病。骨质疏松和相关的骨折是导致死亡的重要原因。本文对目前正处在研究阶段的治疗骨质疏松症的药物进行了综述,包括骨吸收抑制剂,促进骨形成的药物及其他类。     

犬恒牙牙根发育过程中牙髓炎症对细胞凋亡的影响

目的：探讨牙髓炎症对牙根发育过程中细胞凋亡的影响。方法：建立犬年轻恒牙实验性牙髓炎模型,采用原位末端标记技术（TUNEL）观测牙根发育过程中犬恒牙牙髓炎症对各组织中凋亡细胞分布的影响。结果：与炎症区相邻的牙髓组织中细胞凋亡数量增多,参与牙根发育的各种功能细胞（成牙本质细胞、成牙骨质细胞、上皮根鞘细胞、成骨细胞和牙周膜细胞）也出现非生理性的凋亡。结论：牙根发育过程中牙髓炎症状态下细胞凋亡一方面参与牙髓组织自身防御,另一方面则干扰了牙根的正常发育。     

赤芍对内膜增殖机制中丝裂素活化蛋白激酶信号通路的影响探讨

目的:观察赤芍对家兔颈动脉血管成形术后内膜增殖及丝裂素活化蛋白激酶磷酸酶-1(MKP-1)mRNA表达的影响。方法:新西兰白兔随机分为对照及赤芍组,各组均饲喂高脂饲料(普通饲料 2%胆固醇 5%猪油)。赤芍组按剂量给予赤芍提取物:高剂量组(相当于生药3g.kg-1.d-1)、中剂量组(相当于生药2g.kg-1.d-1)、低剂量组(相当于生药1g.kg-1.d-1)。血管成形术后,取材血管行RT-PCR检测MKP-1mRNA表达、形态学测定、免疫组化染色。结果:与对照组比较,增生内膜面积、增生内膜面积/中膜面积显著减少(P<0.05或P<0.01);MKP-1mRNA表达显著增高(P<0.05或P<0.01)。结论:赤芍增加高脂喂养兔颈动脉球囊损伤后MKP-1mRNA表达,减轻内膜增殖程度。表明内膜增殖程度的减低与赤芍阻断MAPK信号通路有关。     

大株红景天胶囊对颈动脉不稳定斑块气虚血瘀证的干预分析

目的:探讨大株红景天胶囊对颈动脉不稳定斑块气虚血瘀证的干预及抗氧化、抗炎和抗血栓形成的作用机制。方法:将符合要求的123例患者,随机按数字表法分为对照组61例和观察组62例。对照组给予抗血小板和调节血脂药物治疗,口服阿司匹林肠溶片,0.1 g/次,1次/d;瑞舒伐他汀钙胶囊,10 mg/次,1次/d。观察组西药使用同对照组,并给予大株红景天胶囊,4粒/次,3次/d。两组疗程均为患者每2周门诊随访1次,连续观察16周。采用彩色多普勒超声测量颈动脉内膜中层厚度(IMT),斑块数量和斑块大小;检测治疗前后甘油三酯(TG),总胆固醇(TC),高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C)水平;进行气虚血瘀证评分;检测治疗前后超氧化物歧化酶(SOD),丙二醛(MDA),超敏C反应蛋白(hs-CRP),同型半胱氨酸(Hcy),基质金属蛋白酶-2(MMP-2),MMP-9,基质金属蛋白酶组织抑制剂-2(TIMP-2),血小板α-颗粒膜蛋白-140(GMP-140),血小板表面P-选择素(CD62 p),溶酶体颗粒糖蛋白(CD63)和血管性假血友病因子(v WF)水平。结果:治疗后,观察组患者IMT薄于对照组、斑块数量少于对照组、斑块大小积分小于对照组(P0.01);治疗后,观察组患者LDL-C低于对照组(P0.01),HDL-C高于对照组(P0.01),气虚血瘀证评分低于对照组(P0.01);观察组患者血清hs-CRP,Hcy,MMP-2,MMP-9均低于对照组,TIMP-2水平高于对照组(P0.01);观察组患者SOD水平高于对照组,MDA水平低于对照组(P0.01);观察组患者GMP-140,v WF,CD62 p和CD63水平均低于对照组(P0.01)。结论:在抗血小板和调节血脂药物治疗的基础上,加服大株红景天胶囊,对治疗气虚血瘀型颈动脉不稳定斑块,具有缩小或减少颈动脉斑块的作用,能调节脂代谢,改善中医证候症状,并具有抗氧化、抗炎和抗血栓形成的作用。     

Heterogeneous iodine-organic chemistry fast-tracks marine new particle formation

The gas-phase formation of new particles less than 1 nm in size and their subsequent growth significantly alters the availability of cloud condensation nuclei (CCN, >30–50 nm), leading to impacts on cloud reflectance and the global radiative budget. However, this growth cannot be accounted for by condensation of typical species driving the initial nucleation. Here, we present evidence that nucleated iodine oxide clusters provide unique sites for the accelerated growth of organic vapors to overcome the coagulation sink. Heterogeneous reactions form low-volatility organic acids and alkylaminium salts in the particle phase, while further oligomerization of small α-dicarbonyls (e.g., glyoxal) drives the particle growth. This identified heterogeneous mechanism explains the occurrence of particle production events at organic vapor concentrations almost an order of magnitude lower than those required for growth via condensation alone. A notable fraction of iodine associated with these growing particles is recycled back into the gas phase, suggesting an effective transport mechanism for iodine to remote regions, acting as a “catalyst” for nucleation and subsequent new particle production in marine air.

Marine aerosol formation contributes significantly to the global radiative budget given the high susceptibility of marine stratiform cloud radiative properties to changes in cloud condensation nuclei (CCN) availability. Atmospheric new-particle-formation is thought to involve nucleation of sulfuric acid with water, ammonia, or amines followed by condensation/growth in the presence of organic vapors (1, 2). Unique in the marine boundary layer (MBL), new particle formation involves sequential addition of HIO₃ or clustering of iodine oxides (I_xO_y) (3, 4). In specific source regions such as coastal zones, seaweed beds, or snowpack/pack-ice, iodine oxide nucleation can be a driving force for nucleation (5–7). Over Arctic waters, nonetheless, one study finds insufficient iodic acid vapors to grow nucleated particles to CCN sizes (8), whereas another study finds that both nucleation and growth are almost exclusively driven by iodic acid (9). Over the open ocean, the supply of iodine oxides has been thought to be limited; however, recent measurements suggest that significant reactive iodine chemistry can occur in these regions (10). Moreover, observational evidence exists for open ocean particle formation and growth, especially when oceanic productivity is high (11, 12). An increase in atmospheric iodine levels in the North Atlantic since the mid-20th century has been shown to be driven by growth of anthropogenic ozone and enhanced subice phytoplankton production (13). While the reported IO concentration (0.4–3.1 ppt) in the remote MBL (10, 14, 15) is likely sufficient for formation of prenucleation clusters (∼1 nm), growth of these initial clusters requires the presence of other condensable vapors (16). Since preexisting aerosol particles act as a strong sink for the nucleated clusters, thus inhibiting atmospheric aerosol and CCN formation (17, 18), this early growth phase is essential for their survival. Whereas sulfuric acid vapor is also involved in nucleation, its level in remote open ocean is generally too low (10⁵ molecules cm⁻³) to support subsequent particle growth, leaving organic vapors as the most plausible alternative for particle growth.In the marine atmosphere, condensing organics must originate from the oxidation of marine volatile organic compounds (VOCs), which predominantly comprise C₁–C₅ VOCs (e.g., isoprene) released from phytoplankton. Principal high volatility oxidation products consist of intermediate oxidized organics (IOOs), such as polyhydric alcohols (e.g., tetrols) or polyfunctional carbonyls (e.g., glyoxal) (19–22). Nonetheless, growth of available prenucleation clusters/nanometer particles requires condensing organic molecules of low effective volatilities (i.e., saturation mass concentration, C* < ∼10⁻³ μg m⁻³); otherwise, preferential condensation of the organic mass to larger-diameter particles would occur (23, 24). Formation of such extremely low-volatility organic compounds (ELVOCs) from gas-phase reaction is well established for monoterpene oxidation products (25, 26).A potential pathway for formation of low-volatility organics could also result from particle-phase chemical reactions induced by iodine oxides in the early stages of marine particle formation. When the underlying chemistry is sufficiently fast, kinetic condensation occurs, resulting in particles with diameters smaller than about 50 nm growing at the same rate (e.g., nm h⁻¹) (24). If, however, particle-phase chemistry is preferentially favored in the smallest particles (i.e., stemming from the higher relative concentration of iodine oxides in freshly formed marine particles), growth of the nucleated particles could proceed more rapidly, as compared to that in which gas-phase chemistry is the source of the low-volatility compounds (23).In this paper, we present experimental results from field measurements as well as laboratory studies of nanometer particle growth and derive a plausible chemical mechanism from the results that can explain the observations of ultrafine particle growth in the marine atmosphere. The results suggest that both iodine and condensed organics contribute to particle growth from a nascent nucleation mode into an ultrafine particle mode. Moreover, laboratory studies of the growth of seed iodine oxide particles (IOP) via heterogeneous reactions with organic vapors suggest a hitherto unrecognized mechanism that fast-tracks the growth of nucleation mode clusters into survivable aerosol particles. In this process, a notable fraction of the iodine associated with these growing particles is recycled back to the gas phase, suggesting a transport mechanism for iodine to remote regions.     

新药开发中药物的盐型选择

成盐是改善弱酸性及弱碱性药物的溶解度和提高药物生物利用度的重要手段.因此,为药物筛选合适的反离子是药品研发过程的关键步骤.本文探讨了筛选反离子时需考虑的因素和成盐对药物的溶解度和溶出速率的影响.     

淫羊藿醇提物调节M2样巨噬细胞极化减少乳腺癌细胞迁移和集落形成的研究

目的 探讨淫羊藿Epimedium brevicornu醇提物对体外巨噬细胞极化调控机制及对M2样巨噬细胞促进4T1细胞迁移和集落形成的影响。方法 采用CCK-8法检测不同浓度淫羊藿醇提物对骨髓来源巨噬细胞（bonemarrowderived macrophages,BMDM）活力的影响,确定淫羊藿醇提物的安全作用浓度;采用Western blotting和q RT-PCR检测淫羊藿醇提物对M2样巨噬细胞标志物精氨酸酶-1(arginase-1,Arg-1)和CD163表达的影响;采用q RT-PCR检测淫羊藿醇提物对M2-肿瘤相关巨噬细胞（tumor-associated macrophages,TAMs）相关基因炎症区域1(found in inflammatory zone 1,Fizz1)、过氧化物酶体增殖物激活受体γ(peroxisome proliferator-activated receptor γ,PPARγ)、几丁质酶3样分子3(chitinase 3-like 3,Ym1)、趋化因子24(C-C motif chemokine ligand 24,CCL24)、巨...