920 resultados para RB Patología


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本文通过对张宣地区西望山群、内蒙乌拉山群麻粒岩相岩石中系统的岩石学、岩石化学、稀土元素地球化学以及Sm-Nd、Rb-Sr、锆石U-Pb及全岩Pb-Pb同位素体系的工作,主要提出以下认识:内蒙、张宣两地麻粒岩均同火成岩类变质而来,基性麻粒岩类的的岩相当于拉斑玄武岩及碱性玄武岩类,中、酸性麻粒岩的原岩是与它们成份相同的花岗岩及花岗闪长岩类。

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在前人有限工作的基础上,选择恒山杂岩,特别是其中的变基性岩包体,以多种同位素地质年代学方法,多元同位素体系制约关系和同位素示踪理论,结合岩石化学,微量元素地球化学对以下问题做出重点研究:1、通过对杂岩,特别是其中的包体的岩石化学,微量元素地球化学和Sm-Nd、RB-Sr、Pb-Pb同位素年代学方法以及Nd-Sr-Pb同位素体系的研究,恢复其原岩类型,判别其所处的构造环境,确定它们的形成时代和其它地质事件发生的时代;2、提出本区早前寒武纪年代地层划分的初步方案;3、讨论区域地壳形成演化历史。

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从主元素化学来看,喀拉通克深成岩以低Ca、Al为特征,而火山岩(玄武岩类)以高Ca、Al为特征;在早期结晶矿物组合上,喀拉通克深成岩为橄榄石、斜方辉石和基性斜长石,而火山岩中斑晶以基性斜长石、背地里斜辉石为主,其次为橄榄石,没有见到斜方辉石斑晶,在Sr-Zr图和Nd-Zr图中二者具有较大差别。利用矿物温度计计算了橄榄石、辉石和斜长石的结晶温度。橄榄石是在稍高于1880℃下开始结晶的,二辉石共存时的温度为1100℃左右,基性斜长石的结晶温度也在1100℃左右,并定性讨论了二号岩体的水含量和氧逸度。比较详细地从定性和定量两方面探讨了岩体成岩压力范围,认为前人计算的7Kb过大。根据橄榄石和斜长石共存现象说明压力小于7Kb,单斜辉石中的铝含量进一步说明压力小于5Kb,最后半定量地利用角闪石地质压力计说明4Kb作为二号岩体的成岩压力是比较可信的。最后探讨了二号岩体所属系列和分异趋势。许多证据表明二号岩体属于钙碱系列岩体,比如结晶矿物类型和顺序等符合obsorn(1962)建立的造山带钙碱系列;在SiO2-K2O图和AFM图中皆落入钙碱系列;辉石的成分变化不具有富铁趋势;所有岩石都有一定量的角闪石;微量元素如Rb、K/Rb、Zr等以及稀土模式与岛弧钙碱岩浆相似。与世界著名钙碱系列岩体比较表明,它们共同的特征是产于造山带环境,岩石都有一定量的含水矿物存在,说明母岩浆富水对于钙碱系列的形成具有重要的作用。若将造岩矿物的成分变化范围投影到AFM图中,可以看出造成二号岩体如此钙碱系列演化线的原因在于岩石中橄榄石和辉石的富铁趋势很弱、岩石中含有较多的黑云母和角闪石以及随着分异进行结晶出越来越多的长石。二号岩体高Si、H2O,低Ca、Al的特征决定了二号岩体的矿物结晶顺序为橄榄石→斜方辉石→拉长石→单斜辉石→角闪石→黑云母,形成相应的岩相为橄榄苏长岩、苏长岩、辉长岩和闪长岩相。辉石的Mg~#值变化很窄,是由于二号岩体含水量较高,使辉石在高En值下停止结晶,而为含水矿物角闪石取代。以上通过对喀拉通克含矿岩体(Y2)的岩石学研究,可以得到如下结论:一、喀拉通克含矿岩体由橄榄苏长岩、苏长岩、辉长岩和闪长岩四个岩相组成。各个岩相是由同一母岩浆经分异形成的。岩体岩相的反环带结构说明岩体不可能是由均匀岩浆一次侵位就地分异形成,而是岩浆深部分异与构造活动结合的产物。二、喀拉通克含矿岩体的母岩浆是产于造山带的一种钙碱性岩浆,以高Si、H2O,低Ca、Al为特征,其母岩浆不z可能是科马提岩、洋中脊拉斑玄武岩、高铝玄武岩或碱性玄武岩浆中的任一种。三、喀拉通克含矿深成岩和该区火山岩在主元素、微量元素及矿物晶出顺序方面存在一定差异,这种差异不大可能是由结晶环境不同造成的,更可能的是两者起源于不同的母岩浆。四、从定性和定量两方面讨论了喀拉通克含矿岩体的成岩压力,从而将4Kb作为该岩体的成岩压力是比较可信的。五、从岩体分异趋势来看,喀拉通克含矿岩体属于钙碱系列岩体。造成钙碱系列分异趋势的主要原因在于岩石中橄榄石和辉石的富铁趋势很弱,岩石含有较多的黑云母和角闪石以及随着分异进行结晶出越来越多的长石。对于以上分异趋势的形成,岩浆富水起着较大的作用。富水一方面使辉石在高En值下停止结晶,以角闪石代替;另一方面使岩浆的氧逸度有所提高。

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本文从区域地质背景、矿区地质特征、成矿物质来源、成矿流体演化以及剪切带对金矿的控制作用等方面利用微量元素和稀土元素指示剂、稳定同位素(H、O、S)和放射性同位素(Rb-Sr、K-Ar、Sm-Nd、U-Pb等)年代学和示踪法以及流体包裹体等研究手段对两个矿区进行了全面的综合对比研究;认识到两个矿区在地质地球化学方面的相同之处及差异;并进一步认识到二甲金矿区在成矿的金背景、韧性剪切带的程序和强度、活动岩浆的岩石类型、成矿物质对地层的依赖性程序等方面可以明显看出二甲矿区金的成矿条件比河台矿区更有利;但河台金矿的规模明显大得多;这反映了矿源层厚度及韧性剪切活动带的规模存在着显著差别;并与糜棱岩原炭类别的差别密切相关。两个矿区大量样品的构造地球化学实验观测结果表明剪切变形改变了岩石、矿物的结构、构造及岩石矿物的成份、矿物的化学成份等;成矿物质迁移的机制是压溶导致粒化溶解及剪切溶解并使成矿物质沿特定方向(剪切带中)迁移;软弱面的存在是剪切带发育的前提;物质迁移的首要条件是含Fe和Si的粒间流体的存在;而沉淀的优势微构造是微裂隙及矿物颗粒边缘。

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Reversed-phase high-performance liquid chromatographic (RP-HPLC) retention parameters, which are determined by the intermolecular interactions in retention process, can be considered as the chemical molecular descriptors in linear free energy relationships (LFERs). On the basis of the characterization and comparison of octadecyl-bonded silica gel (ODS), cyano-bonded silica gel (CN), and phenyl-bonded silica gel (Ph) columns with linear solvation energy relationships (LSERs), a new multiple linear regression model using RP-HPLC retention parameters on ODS and CN columns as variables for estimation of soil adsorption coefficients was developed. It was tested on a set of reference substances from various chemical classes. The results showed that the multicolumn method was more promising than a single-column method was for the estimation of soil adsorption coefficients. The accuracy of the suggested model is identical with that of LSERs.

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A phenylurea herbicides-selective molecularly imprinted polymer (MIP) was prepared using N-(4-isopropylphenyl)-N'-butyleneurea as a dummy template and toluene as a porogen. The experimental results showed that the optimum molar ratio of template, functional monomer (MAA) and cross-linker (EDMA) was 1:8:20. Scatchard analysis showed that two classes of binding sites were formed in the imprinted polymer with dissociation constants of 26.81 mu L mol l(-1) and 1.428 mmol l(-1). The affinity and selectivity of MIP for phenylurea herbicides were studied. Among the 14 phenylurea herbicides tested, the MIP prepared showed obviously high affinity and selectivity for 10 chemicals (monuron, diuron, isoproturon, fenuron, chlortoluron, difenoxuron, metoxuron, neburon, buturon and fluometuron) with dichloromethane containing 10% hexane as mobile phase while non-imprinted polymer showed very low affinity for all the phenylurea herbicides tested. The experimental and calculated results also indicated that the size and property of the group at the N' position of phenylurea molecules have great influence on the affinity of MIP for them and the recognition site is mainly located at the N' position of phenylurea herbicides. (c) 2005 Elsevier B.V. All rights reserved.

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Uniformly carbon-covered alumina (CCA) was prepared via the carbonization of sucrose highly dispersed on the alumina surface. The CCA samples were characterized by XRD, XPS, DTA-TG, UV Raman, nitrogen adsorption experiments at 77 K, and rhodamine B (RB) adsorption in aqueous media. UV Raman spectra indicated that the carbon species formed were probably conjugated olefinic or polycyclic aromatic hydrocarbons, which can be considered molecular subunits of a graphitic plane. The N(2) adsorption isotherms, pore size distributions, and XPS results indicated that carbon was uniformly dispersed on the alumina surface in the as-prepared CCA. The carbon coverage and number of carbon layers in CCA could be controlled by the tuning of the sucrose content in the precursor and impregnation times. RB adsorption isotherms suggested that the monolayer adsorption capacity of RB on alumina increased drastically for the sample with uniformly dispersed carbon. The as-prepared CCA possessed the texture of alumina and the surface properties of carbon or both carbon and alumina depending on the carbon coverage.

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Objective The aim of this study was to investigate the associations between alleles of the hypoxia-inducible factor 1A (HIF1A) C1772T polymorphism and several physiological responses to hypoxia, including the hypoxic ventilatory response (HVR), and serum erythropoietin (EPO), arterial oxygen saturation (Sao2), and acute mountain sickness (AMS) responses during 8 hours of exposure to normobaric hypoxia. Methods A total of 76 males participated in the study; 52 participants completed an 8-hour exposure to 12.7% oxygen, during which time Sao2, EPO concentrations, and AMS scores were measured, while 62 individuals took part in an HVR trial (in total 38 individuals completed both protocols). DNA was obtained from leukocytes, and a 346-bp fragment of the HIF1A gene containing the C1772T polymorphism was amplified using polymerase chain reaction. Fragments were sequenced to reveal individual genotypes, and the associations between HIF1A genotype and EPO, Sao2, AMS responses to hypoxia and HVR were examined. Results The magnitude of the hypoxic responses was highly variable between individuals. The increase in participants' EPO responses ranged from 89% to 388% of baseline values following hypoxia, while Sao2 values during the exposure ranged from 71% to 89%. The HVR ranged from −0.04 to +2.18 L · min−1 · Sao2%−1 among participants. No significant differences in EPO, Sao2, AMS, or HVR results were observed between the HIF1A CC genotype and the combined CT/TT genotype group. Conclusion In this study, the HIF1A C1772T polymorphism does not appear to influence EPO, Sao2, or AMS responses during acute hypoxic exposure, or the magnitude of the HVR.

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Las infecciones bacterianas de la piel y partes blandas constituyen una patología frecuente como consulta en los servicios de urgencias. Los cuadros más frecuente son las celulitis, que tienen un buen pronóstico, pero ocasionalmente se ven infecciones más profundas que afectan a tejido celular subcutáneo, fascia y músculo. En este caso el diagnóstico y tratamiento precoces son fundamentales para el pronóstico del paciente. Describimos un caso de Gangrena de Fournier que a pesar del un diagnóstico y tratamiento precoces en el servicio de urgencias, produjo la muerte del paciente. 

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La dieta es un factor importante para la salud de las personas; debe adaptarse a nuestras necesidades fisiológicas que variarán en función de la edad, el sexo, la actividad física, enfermedades… Es importante una dieta equilibrada para que no exista un exceso o defecto de nutrientes en nuestro organismo que colabore a agudizar patologías existentes. Pero, desafortunadamente; hoy en día no le se presta la atención que se merece y se descuida bastante, sin entender que dependiendo de lo que comemos nuestro organismo será capaz de poder trabajar y realizar todo lo necesario; traducido, en que será posible que realicemos todas las actividades que queramos a lo largo del día. Así; este trabajo se desarrolla en el ámbito domiciliario de los enfermos en la salida hospitalaria de una exacerbación: enfocado a cubrir las necesidades específicas de las personas afectadas de EPOC, y para ello se presenta una propuesta de dieta que sirva de guía para esta parte de la población. Enmarcado en el lugar: Hospital Público de Navarra. Servicio de Neumología. Población diana: Pacientes al alta hospitalaria en el año 2010, edad entre 50-60 años. El objetivo es servir de apoyo a las personas afectadas de una patología crónica y que cada día va en aumento En la memoria del complejo hospitalario de Navarra del año 2010; aparece como enfermedad más habitual en el motivo de ingreso en la clasificación de GRD (Grupos de Diagnóstica Relacionado GRD). Se observa una pequeña disminución en el número de ingresos del año 2010 respecto al pasado, así como la duración del ingreso; sin embargo, no deja de ser la enfermedad que mayor presencia hospitalaria ha tenido.

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Wydział Neofilologii: Katedra Studiów Azjatyckich

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Carbon Capture and Storage may use deep saline aquifers for CO(2) sequestration, but small CO(2) leakage could pose a risk to overlying fresh groundwater. We performed laboratory incubations of CO(2) infiltration under oxidizing conditions for >300 days on samples from four freshwater aquifers to 1) understand how CO(2) leakage affects freshwater quality; 2) develop selection criteria for deep sequestration sites based on inorganic metal contamination caused by CO(2) leaks to shallow aquifers; and 3) identify geochemical signatures for early detection criteria. After exposure to CO(2), water pH declines of 1-2 units were apparent in all aquifer samples. CO(2) caused concentrations of the alkali and alkaline earths and manganese, cobalt, nickel, and iron to increase by more than 2 orders of magnitude. Potentially dangerous uranium and barium increased throughout the entire experiment in some samples. Solid-phase metal mobility, carbonate buffering capacity, and redox state in the shallow overlying aquifers influence the impact of CO(2) leakage and should be considered when selecting deep geosequestration sites. Manganese, iron, calcium, and pH could be used as geochemical markers of a CO(2) leak, as their concentrations increase within 2 weeks of exposure to CO(2).

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BACKGROUND: To our knowledge, the antiviral activity of pegylated interferon alfa-2a has not been studied in participants with untreated human immunodeficiency virus type 1 (HIV-1) infection but without chronic hepatitis C virus (HCV) infection. METHODS: Untreated HIV-1-infected volunteers without HCV infection received 180 microg of pegylated interferon alfa-2a weekly for 12 weeks. Changes in plasma HIV-1 RNA load, CD4(+) T cell counts, pharmacokinetics, pharmacodynamic measurements of 2',5'-oligoadenylate synthetase (OAS) activity, and induction levels of interferon-inducible genes (IFIGs) were measured. Nonparametric statistical analysis was performed. RESULTS: Eleven participants completed 12 weeks of therapy. The median plasma viral load decrease and change in CD4(+) T cell counts at week 12 were 0.61 log(10) copies/mL (90% confidence interval [CI], 0.20-1.18 log(10) copies/mL) and -44 cells/microL (90% CI, -95 to 85 cells/microL), respectively. There was no correlation between plasma viral load decreases and concurrent pegylated interferon plasma concentrations. However, participants with larger increases in OAS level exhibited greater decreases in plasma viral load at weeks 1 and 2 (r = -0.75 [90% CI, -0.93 to -0.28] and r = -0.61 [90% CI, -0.87 to -0.09], respectively; estimated Spearman rank correlation). Participants with higher baseline IFIG levels had smaller week 12 decreases in plasma viral load (0.66 log(10) copies/mL [90% CI, 0.06-0.91 log(10) copies/mL]), whereas those with larger IFIG induction levels exhibited larger decreases in plasma viral load (-0.74 log(10) copies/mL [90% CI, -0.93 to -0.21 log(10) copies/mL]). CONCLUSION: Pegylated interferon alfa-2a was well tolerated and exhibited statistically significant anti-HIV-1 activity in HIV-1-monoinfected patients. The anti-HIV-1 effect correlated with OAS protein levels (weeks 1 and 2) and IFIG induction levels (week 12) but not with pegylated interferon concentrations.

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The transition of the mammalian cell from quiescence to proliferation is a highly variable process. Over the last four decades, two lines of apparently contradictory, phenomenological models have been proposed to account for such temporal variability. These include various forms of the transition probability (TP) model and the growth control (GC) model, which lack mechanistic details. The GC model was further proposed as an alternative explanation for the concept of the restriction point, which we recently demonstrated as being controlled by a bistable Rb-E2F switch. Here, through a combination of modeling and experiments, we show that these different lines of models in essence reflect different aspects of stochastic dynamics in cell cycle entry. In particular, we show that the variable activation of E2F can be described by stochastic activation of the bistable Rb-E2F switch, which in turn may account for the temporal variability in cell cycle entry. Moreover, we show that temporal dynamics of E2F activation can be recast into the frameworks of both the TP model and the GC model via parameter mapping. This mapping suggests that the two lines of phenomenological models can be reconciled through the stochastic dynamics of the Rb-E2F switch. It also suggests a potential utility of the TP or GC models in defining concise, quantitative phenotypes of cell physiology. This may have implications in classifying cell types or states.

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The beta-adrenergic receptor kinase (beta ARK) phosphorylates the agonist-occupied beta-adrenergic receptor to promote rapid receptor uncoupling from Gs, thereby attenuating adenylyl cyclase activity. Beta ARK-mediated receptor desensitization may reflect a general molecular mechanism operative on many G-protein-coupled receptor systems and, particularly, synaptic neurotransmitter receptors. Two distinct cDNAs encoding beta ARK isozymes were isolated from rat brain and sequenced. The regional and cellular distributions of these two gene products, termed beta ARK1 and beta ARK2, were determined in brain by in situ hybridization and by immunohistochemistry at the light and electron microscopic levels. The beta ARK isozymes were found to be expressed primarily in neurons distributed throughout the CNS. Ultrastructurally, beta ARK1 and beta ARK2 immunoreactivities were present both in association with postsynaptic densities and, presynaptically, with axon terminals. The beta ARK isozymes have a regional and subcellular distribution consistent with a general role in the desensitization of synaptic receptors.