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A hipertensão arterial resistente (HAR) é definida pela persistência da pressão arterial (PA)≥140/90mmHg a despeito do uso de 3 anti-hipertensivos em doses plenas, incluindo diurético. Revisão recente da literatura mostra poucos estudos avaliando o perfil e o comportamento da função endotelial em pacientes com HAR. Objetiva avaliar a função endotelial em pacientes hipertensos resistentes. Estudo transversal com 60 pacientes que foram avaliados em uma visita (V3) de um estudo longitudinal, onde numa primeira fase todos pacientes tiveram padronização do tratamento anti-hipertensivo. Foram incluídos pacientes (V0) com PA>160/100mmHg e <220mmHg e todos receberam clortalidona 25mg/dia e enalapril 20mg 2x/dia ou losartana 50mg 2x/dia (intolerantes ao enalapril). Visita 1: se PA>140/90mmHg acrescentou-se anlodipino 5mg/dia, foi realizado avaliação laboratorial de rotina do hipertenso e monitorização ambulatorial da PA-24h (MAPA). Visita 2: se PA>140/90mmHganlodipino foi titulado para 10mg/dia. Visita 3: todos os pacientes receberam avaliação clínica, da pressão arterial por MAPA, laboratorial de rotina e da função endotelial. Formaram-se dois grupos: os que controlaram a PA, grupo hipertensão arterial controlada (HAC); e os que permaneceram com PA de consultório>140/90mmHg e PA na MAPA-24h>130/80mmHg, foram considerados resistentes. O grupo HAR recebeu aleatoriamente espironolactona ou clonidina por mais 12 semanas para tentar controlar a PA e o grupo HAC teve assistência farmacológica mantida no mesmo período. A PA foi avaliada por método oscilométrico com aparelho digital semi-automático Microlife modelo BP3AC1-1PC e MAPA por aparelho SpaceLabs 90207. A função endotelial avaliada através de tonometria arteriolar periférica (PAT) pelo Endo-PAT2000 e por biomarcadores (I-CAM-1, V-CAM-1, VEGF, MCP-1, IL-6, adiponectina) através da técnica LuminexTMxMAP. Dos 60 pacientes avaliados, 36 controlaram a PA, grupo HAC, e 24 permaneceram resistentes ao tratamento, grupo HAR, na visitaV3. Na avaliação da PA pela MAPA-24h observamos que no grupo HAC a PAS-24h foi de 121,1+1,7mmHg e no grupo HAR 147+3,3mmHg, enquanto a PAD-24h no grupo HAC foi de 76,64+1,5mmHg e no grupo HAR 88,58+2,4mmHg (p<0,0001). O descenso noturno, apesar de maior no grupo HAC, não apresentou significância estatística entre os dois grupos (p> 0,05). A função endotelial avaliada através do PAT mostrou índice de hiperemia reativa de 1,850,056 e 1,65+0,074 nos grupos HAC e HAR respectivamente (p= 0,036) e quando avaliada através dos biomarcadores observamos: ICAM-1 (HAC= 186,6+12,65 vs HAR= 240,9+23,76ng/ml, p= 0,038), VCAM-1 (HAC= 627,137,09vs HAR= 706,086,10ng/ml, p= 0,372),VEGF (HAC= 403,394,91 vs HAR= 612,788,27pg/ml, p= 0,123) e MCP-1 (HAC= 694,969,09 vs HAR= 787,052,80pg/ml, p= 0,315). Na avaliação dos biomarcadores inflamatórios, observamos IL-6 no grupo HAC= 1,8970,2165pg/mle no HAR= 9,7934,421pg/ml (p= 0,027) e adiponectina no grupo HAC= 105701516pg/ml e HAR= 84221295pg/ml (p=0,301). A razão de prevalência do comprometimento da função endotelial no grupo HAR foi de 54% (OR= 3,55; 95% IC 1,18- 10.67; p= 0,029). No presente trabalho, as análises das variáveis estudadas na visita V3, mostraram que os pacientes com HAR têm maior comprometimento da função endotelial que os pacientes com HAC.

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原产于亚马逊河流域的水生植物凤眼莲(Eichhornia crassipes)在花部结构上有三种花型(L、M和S),故其配殖系统(mating system)为典型的三型花柱(tristyly)。但在入侵地区,它却常只有M和L两种花型,其中尤以M型占据绝对优势,使有性繁殖水平大为下降。为了解释凤眼莲在入侵过程中,花型频率为何发生变化以及该变化对其在入侵地的适应性进化上有何影响,作者在中国西南的两个居群中连续两年开展了野外生长和人工授粉实验,对比分析水面和泥地两类不同生境中M和L在克隆生长、生物量积累以及有性繁殖水平等方面的异同,并利用RAPD、 ISSR片段比较了具M型和L型花植物个体间的遗传变异水平。对三型花柱这一长期引人注目的遗传模式的分子位点也尝试了连锁片段的克隆和测序。 克隆生长的对比实验发现,在2004年,漂浮生长的M个体平均克隆分株数为25.37,L为21.20,前者显示较强的克隆生长能力(t=2.252, P< 0.05);2005年的实验再次证实M(每个个体19.83个分株)比L(每个个体15.53分株)表现出了显著较强的克隆优势(t=2.631,P<0.001)。M较L多产生克隆约24%。 但在岸边泥地上固着生长时,2004年L个体平均克隆分株为16.20,M 为10.17个分株。L表现出了更强的克隆生长能力(t=4.788,p<0.001),与漂浮生长状况下的情形恰恰相反,暗示M与L个体可能存在一定的生态位分化。这种分化可能是在入侵过程中形成的,也可能反映了原产地亚马孙流域旱涝交替造成的固着生长与漂浮生长交替发生的种内适应性。 生物量(干重)的对比分析发现,M个体在漂浮生长和固着生长的情况下都比L有着更高的生物量积累(漂浮生长实验:t=6.173,p<0.005(2004年);t=6.99,p<0.001(2005年)。固着生长实验:t=4.029,p<0.001)。生物量对凤眼莲的竞争和过冬有着一定的作用,因此较大的生物量积累可能是M个体在当地气候和环境中逐渐适应的一个结果。 有性繁殖的实验包括了实验个体的花序数与花朵数、自交与异交人工授粉的结实情况以及种子萌发率等方面的对比分析。结果表明,虽然M和L个体在花序数和花朵数上不存在显著差异,但是M个体在自交和异交的种子产量上比L略高,尤其是自交的种子产量,M显著高于L(M平均每个蒴果的自交种子产量为139.8,L为76.2)。以各100粒种子进行萌发实验,发现两花型之间在种子萌发率上不存在显著差异。对于M而言,其自交种子产量远大于异交种子产量 (139.8 vs. 93.3),且种子萌发率也略大于异交的种子萌发率(自交种子萌发率45.47%,异交种子萌发率 30.73%)。结合以上的实验结果,本文认为M基因型优势的形成可能与M个体与当地环境长期适应导致的生长与繁殖 上的优势有关。M的本地适应性是建立在特定的遗传背景上时,异交反而会破坏这种遗传组合,造成远交衰退。 对40个M和30个L个体进行20个RAPD引物和20个ISSR引物的遗传分析时发现,所有个体在RAPD表型上没有区别,但是在M中出现了3个ISSR表型,在L中出现了2个ISSR表型。本文还尝试利用RAPD技术扫描与三型花柱的遗传位点连锁的DNA片段。在146个RAPD随机引物中,初步发现两个候选片段,一个750bp,另一个2 000bp;已对它们进行了克隆、测序。 这些初步实验表明凤眼莲在我国的入侵可能伴随着基因型的差异表现和居群遗传分化,这种基因型的差异表现对该植物的成功入侵具有作用。其中,花型为M的个体的优势生长解释了该花型在中国分布区内的主导地位。推测该生长优势的遗传基础可能来源于基因组内较高的杂合子水平和在入侵地较长的适应历史,但最终结论尚有待进一步的实验证据。

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一、 春化相关基因全长cDNA序列及其启动子的克隆与分析研究 通过建立小麦(Triticum aestivum. L. cv Jingdong No.1)胚芽春化cDNA文库,以春化相关基因VER2的3’端序列为探针,筛选获得全长1195 bp cDNA序列,它编码300个氨基酸。在VER2中存在植物疾病抗性反应蛋白和茉莉酸诱导凝集素两种蛋白的结构域。另外在VER2蛋白中存在核定位信号和多种磷酸酶的作用位点,VER2可能参与了多种调控途径。 以VER2基因的cDNA为探针,利用改进的池式PCR以及高密度膜杂交筛选的方法,从小麦TAC基因组文库中获得41,788 bp的基因组克隆,该序列含有11个基因,其中VER2基因位于第三个基因。VER2基因组序列含有3个内含子,4个外显子与cDNA序列100%同源。通过对转录起始点和转录终止点的分析,进一步证明从cDNA文库筛选得到的VER2基因为全长序列。 对VER2基因的上游启动子区域进行分析,发现基因上游启动子区存在三个小的重复序列,每个片段有482 bp,另有两个较大的重复序列,每个片段有2,161 bp。对上游2.8 kb启动子区(不含重复序列)的响应元件分析,其包括ABA响应元件(ABRE)、茉莉酸甲酯响应元件(Me-JARE)、胚乳特异性表达元件、参与淀粉酶合成的元件以及存在类似GA响应元件(ATAACAAAC)如ATAACATAC等等。根据VER2基因上游6 kb序列结构特点,将VER2启动子区域进行缺失突变形成10个片段,分别以GUS和GFP为报告基因构建成瞬间表达载体和植物表达载体等四类质粒。通过基因枪方法将最大片段(6 kb)驱动GFP报告基因的瞬间表达载体转入经春化处理或未春化处理的小麦幼叶中,结果发现GFP在春化处理的幼叶中表达,而在未春化处理的幼叶中不表达,说明VER2基因的启动子驱动基因转录受春化处理调控。 二、 小麦矮化突变体的研究 通过对小麦矮化突变体gaid遗传生理分析发现该突变体为半显性阻断GA信号途径,由此发现在赤霉素信号途径中,α-淀粉酶的诱导一定程度上通过某些与株高相关的基因控制。突变体gaid呈现对高浓度的脱落酸更敏感,当ABA浓度达到10-6M时,突变体的生长几乎完全受到了抑制,而野生型的生长需要ABA浓度达到10-5M时才能完全受到抑制。通过突变体gaid对乙烯等抑制型生长调节剂的响应实验研究,首次提出GA调控植物伸长生长存在两条信号途径,即GA基础水平信号途径(GA basal level signaling pathway)和GA正常水平信号途径(GA normal level signaling pathway),而乙烯以及高浓的GA合成抑制剂(如PAC)是通过第一条途径(GA基础水平信号途径)起作用。光形态建成中对植株生长的抑制作用存在独立于GA的信号途径。 突变体gaid的根系在强光照(63.5 Es-1m-2)和培养基内(低氧)的生长条件下,表现出弯曲、变短、加粗等异常性状,而随光照强度的减弱,这种根系异常生长的表型也减弱,在暗培养中则完全消失,但无论在哪种环境条件下,相对野生型对照而言,突变体的种子根短、侧根少。低浓度的ABA(10-8M)可以恢复突变体gaid根系在强光低氧条件下的正常生长发育。然而利用IAA及其极性运输的抑制剂(TIBA)、乙烯生物合成前提物(ACC)及合成抑制剂(AOA)处理突变体gaid,并没有发现突变体根系的生长发育得到恢复。 突变体gaid可能是一个新的属于小麦GA信号途径中的负调控基因(GAID)发生了突变或超表达,导致其负调控作用增强,呈现半显性的矮化突变。在与另一已知小麦GA信号途径中的负调控基因RHT的关系研究上发现,GAID可能对RHT蛋白磷酸化后的降解途径起抑制作用。通过双向电泳发现突变体gaid与野生型对照(京冬1号)在生长过程中存在差异蛋白,这将有助于对GA信号途径分子机理的深入研究。

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The bastard grunt (Pomadasys incisus) is one of the most abundant coastal demersal fishes inhabiting the Canary Islands. Age and growth were studied from samples collected between October 2000 and September 2001. Growth analysis revealed that this species is a fast growing and moderately short-lived species (ages up to seven years recorded). Length-at-age was described by the von Bertalanffy growth model (L∞=309.58 mm; k=0.220/year; t0=–1.865 year), the Schnute growth model (y1=126.66 mm; y2=293.50 mm; a=–0.426; b= 5.963), and the seasonalized von Bertalanffy growth model (L∞=309.93 mm; k=0.218/ year; t0= –1.896 year; C=0.555; ts=0.652). Individuals grow quickly in their first year, attaining approximately 60% of their maximum length; after the first year, their growth rate drops rapidly as energy is probably diverted to reproduction. The parameters of the von Bertalanffy weight growth curve were W∞=788.22 mm; k=0.1567/year; t0= –1.984 year. Fish total length and otolith radius were closely correlated, r2=0.912. A power relationship was estimated between the total length and the otolith radius (a=49.93; ν=0.851). A year’s growth was represented by an opaque and hyaline (translucent) zone—an annulus. Backcalculated lengths were similar to those predicted by the growth models. Growth parameters estimated from the backcalculated sizes at age were L∞=315.23 mm; k=0.217/year; and t0= –1.73 year.

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Ninety-six bigeye tuna (88– 134 cm fork length) were caught and released with implanted archival (electronic data storage) tags near fish-aggregating devices (FADs) in the equatorial eastern Pacific Ocean (EPO) during April 2000. Twenty-nine fish were recaptured, and the data from twenty-seven tags were successfully downloaded and processed. Time at liberty ranged from 8 to 446 days, and data for 23 fish at liberty for 30 days or more are presented. The accuracy in geolocation estimates, derived from the light level data, is about 2 degrees in latitude and 0.5 degrees in longitude in this region. The movement paths derived from the filtered geolocation estimates indicated that none of the fish traveled west of 110°W during the period between release and recapture. The null hypothesis that the movement path is random was rejected in 17 of the 22 statistical tests of the observed movement paths. The estimated mean velocity was 117 km/d. The fish exhibited occasional deep-diving behavior, and some dives exceeded 1000 m where temperatures were less than 3°C. Evaluations of timed depth records, resulted in the discrimination of three distinct behaviors: 54.3% of all days were classified as unassociated (with a floating object) type-1 behavior, 27.7% as unassociated type-2 behavior, and 18.7% as behavior associated with a floating object. The mean residence time at floating objects was 3.1 d. Data sets separated into day and night were used to evaluate diel differences in behavior and habitat selection. When the fish were exhibiting unassociated type-1 behavior (diel vertical migrations), they were mostly at depths of less than 50 m (within the mixed layer) throughout the night, and during the day between 200 and 300 m and 13° and 14°C. They shifted their average depths in conjunction with dawn and dusk events, presumably tracking the deep-scattering layer as a foraging strategy. There were also observed changes in the average nighttime depth distributions of the fish in relation to moon phase.

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The stock size and biology of Johnius glaucus (Day) resource off the northwest coast of India were studied for 1982-83 and 1983-84. The total length at the end of 6, 12, 18, 24 and 26 months was 121 mm, 183 mm, 237 mm, 261 mm and 264 mm respectively. The length growth parameters were: L∞=300 mm, K=0.0807 (monthly) and t(sub)0=-0.51 month. The weight growth parameters were: W∞= 317g, K=0.0762 (monthly) and t(sub)0= -0.41 month. The exploited stock mainly composed of 1/2 + and 1+ age groups. The annual Z, M and F were 2.34, 1.49 and 0.85 respectively. The l(sub)b, t(sub)b, l(sub)r, t(sub)r and selection factor K were 155 mm, 0.75 year, 65 mm, 0.25 year and 3.875 respectively. The Yw/R was optimum at the exploitation rate (E) of 0.75 and coded mesh size of 37 mm. The total stock for 1982-83 and 1983-84 was 14,624 and 26,190 tons respectively. The standing stock of 1982-83 and 1983-84 was 5,645 and 10,110 tons respectively. The MSY for 1982-83 and 1983-84 was 6,623 and 11,788 tons respectively. The F and Z were lowest in 0+ age group and highest in 1+ age group.

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A detailed experimental investigation was conducted into the interaction of a converted wake and a separation bubble on the rear suction surface of a highly loaded low-pressure (LP) turbine blade. Boundary layer measurements, made with 2D LDA, revealed a new transition mechanism resulting from this interaction. Prior to the arrival of the wake, the boundary layer profiles in the separation region are inflexional. The perturbation of the separated shear layer caused by the converting wake causes an inviscid Kelvin-Helmholtz rollup of the shear layer. This results in the breakdown of the laminar shear layer and a rapid wake-induced transition in the separated shear layer.

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本发明涉及海洋化工工程技术领域,具体讲是一种壳聚糖季铵盐及其制备和应用。壳聚糖季铵盐为式(1)所示的化合物,其中n的平均取值范围是1035-1242。制备:5-氯水杨醛与4-氨基吡啶以等摩尔比于无水乙醇中,60-90℃回流反应4h,所得产物旋转蒸发除去液体,得到黄色固体用无水乙醇重结晶,加入二甲亚砜使黄色固体完全溶解,而后加入氯乙酰壳聚糖, 50-70℃反应16-24h,干燥即得低分子量壳聚糖季铵盐衍生物;其中黄色固体与低分子量氯乙酰壳聚糖摩尔比为1:2。本发明所的物质水溶性良好,取代度较高,具有良好的抑菌活性,可以广泛应用于医药和农业等领域。