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21.
目的研究AEG-1在大肠癌组织和细胞中的表达,探讨AEG-1通过调控上皮间质转化和耐药参与大肠癌的进展。方法采用qRT-PCR检测AEG-1在大肠癌组织和细胞中的表达,统计AEG-1对大肠癌患者生存率的影响,分析其在不同癌症分期患者中的表达差异,并分析AEG-1表达量与大肠癌诊断敏感性的关系。采用体外实验将si-NC、pc-DNA-NC、si-AEG-1、pc-DNA-AEG-1转染到大肠癌SW116和LOVO细胞中,然后通过qRT-PCR检测转染效率以及AEG-1在两细胞系中的表达情况。采用CCK-8和克隆形成实验检测AEG-1对大肠癌细胞增殖的影响;采用流式细胞术检测转染后上皮间质转化和耐药情况的变化;采用Western blotting检测转染后上皮间质转化和耐药相关蛋白N-cadherin、E-cadherin、MRP的变化情况。结果 77例大肠癌患者组织中AEG-1表达水平明显高于对照组。浸润T3+T4期的患者中AEG-1的表达水平高于浸润T1+T2期患者。Ⅲ+Ⅳ期患者中AEG-1的表达水平高于Ⅰ+Ⅱ期。AEG-1高表达组患者OS时间明显低于低表达组。AEG-1表达量与大肠癌诊断敏感性之间呈显著正相关。在LOVO细胞系中,降低AEG-1表达后其细胞活力、侵袭力明显降低,同时间质细胞标志蛋白N-cadherin、上皮细胞标志蛋白E-cadherin、多药耐药相关蛋白MRP表达量降低。在SW116细胞系中,过表达AEG-1后上皮间质转化、耐药相关蛋白表达量显著升高。结论 AEG-1在大肠癌组织和细胞中的表达量明显上升,AEG-1通过调控上皮间质转化和耐药参与大肠癌的发生发展,为大肠癌的治疗提供了新的理论依据和新的靶点。  相似文献   
22.
Summary Pressure infiltration of water into a leaf via the stomatal pores can be used to quickly determine whether all stomata are open, or as recently described for several mesophytic and xerophytic species, whether there is a non-homogeneous distribution of stomatal opening (stomatal patchiness) on the leaf surface. Information about this phenomenon is important since the commonly used algorithms for calculation of leaf conductance from water vapor exchange measurements imply homogeneously open stomata, which in the occurrence of stomatal patchiness will lead to erroneous results. Infiltration experiments in a growth chamber with leaves of the Mediterranean evergreen shrub Arbutus unedo, carried out under simulated Mediterranean summer day conditions, where the species typically exhibits a strong midday stomatal closure, revealed a temporary occurrence of stomatal patchiness during the phase of stomatal closure in the late morning and during the stomatal reopening in the afternoon. Leaves were, however, found to be fully (i.e. homogeneously) infiltratable in the morning and in the evening. At midday during maximum stomatal closure, leaves were almost non-infiltratable. During the day, the infiltrated amount of water was found to be linearly correlated with porometer measurements of leaf conductance of the same leaves, carried out with the attached leaves immediately before infiltration.  相似文献   
23.
Microstructured composite beams reinforced with complex three-dimensionally (3D) patterned nanocomposite microfilaments are fabricated via nanocomposite infiltration of 3D interconnected microfluidic networks. The manufacturing of the reinforced beams begins with the fabrication of microfluidic networks, which involves layer-by-layer deposition of fugitive ink filaments using a dispensing robot, filling the empty space between filaments using a low viscosity resin, curing the resin and finally removing the ink. Self-supported 3D structures with other geometries and many layers (e.g. a few hundreds layers) could be built using this method. The resulting tubular microfluidic networks are then infiltrated with thermosetting nanocomposite suspensions containing nanofillers (e.g. single-walled carbon nanotubes), and subsequently cured. The infiltration is done by applying a pressure gradient between two ends of the empty network (either by applying a vacuum or vacuum-assisted microinjection). Prior to the infiltration, the nanocomposite suspensions are prepared by dispersing nanofillers into polymer matrices using ultrasonication and three-roll mixing methods. The nanocomposites (i.e. materials infiltrated) are then solidified under UV exposure/heat cure, resulting in a 3D-reinforced composite structure. The technique presented here enables the design of functional nanocomposite macroscopic products for microengineering applications such as actuators and sensors.  相似文献   
24.
马鸣超  姜昕  李俊  王静 《微生物学报》2008,35(5):0731-0736
本文通过构建16S rDNA克隆文库开展了人工快速渗滤(CRI)系统表层(10 cm深)细菌种群多样性研究, 结果表明, 在CRI系统表层填料中细菌多样性十分丰富, 存在7个主要类群, 其中不可培养的酸杆菌纲(uncultured Acidobacteria)和其它不可培养细菌(uncultured bacteria)在整个克隆文库中比例最大, 比例为53.72%, 其次是浮霉菌纲(uncultured planctomycete)和β-变形菌纲(β-proteobacterium), 分别占文库比例的13.89%和8.33%; 克隆文库中反硝化菌的比例高于亚硝化单胞菌属细菌(0.925%), 没有出现Nitrospira属的克隆子。本文通过16S rDNA克隆文库揭示了在生物膜上存在的优势菌为不可培养菌, 而假单胞菌(Pseudomonas aeruginosa)和紫色色杆菌(Chromobacterium sp.)等在平板分离培养中出现的频率较高, 两种方法之间的结果存在差异。本研究采用16S rDNA克隆文库方法揭示的结果, 将为CRI系统生物降解的进一步提高提供依据。  相似文献   
25.
Abstract. The vegetation succession in a floating mire was studied in relation to management and hydrological conditions in a former peat cutting area in the northern part of the Netherlands. An existing map showed that in 1956 the vegetation consisted mainly of meadows, reedbeds and rich fen vegetation while a recent survey revealed that this picture had completely changed in 1989. The area had mainly become woodland but part had remained open, due to the continuation of a mowing regime. The timing of the mowing appears to be critical, especially during the earlier phases of the succession. Winter-mowing favours the development of eutrophic reedbeds, while summer-mowing promotes mesotrophic sedge communities. In the course of time these succession lines converge increasingly towards acidic vegetation types. The development from open water to embryonic bog differed greatly between sites with a similar management regime. Mostly this took only a few decades but in a few sites the vegetation had hardly changed since 1956. Whereas the former sites were acid throughout the profile, the latter showed a high pH from top to bottom. It is obvious that acidification does not occur as long as alkaline surface water can move freely underneath the floating mat. As soon as a given site becomes disconnected from the surface water the depletion of bases by infiltrating rainwater is no longer compensated. A rough estimate of the acidification rate shows that in an infiltration area three decades are sufficient for a floating mat of 40 cm to become completely decalcified. This corresponds well to the observed succession from rich fens to embryonic bogs in the same period. It is suggested that the best way to preserve rich fen vegetation is to start the succession anew by digging turf ponds.  相似文献   
26.
摘要 目的:探讨促性腺激素释放激素(Gonadotropin releasing hormone,GnRH)类似物对子宫肌瘤大鼠模型血液黏度、子宫系数和炎性细胞浸润的影响。方法:子宫肌瘤大鼠模型(n=36)随机平分为三组-模型组、米非司酮组与GnRH类似物组,分别给予腹腔注射0.15 ml的生理盐水、2 mg/kg米非司酮与2 mg/kg GnRH类似物,每周1次,持续8周。结果:米非司酮组与GnRH类似物组治疗第4周与第8周的全血比黏度、卵泡刺激素(FSH)、黄体生成素(LH)值都低于模型组(P<0.05),GnRH类似物组低于米非司酮组(P<0.05)。米非司酮组与GnRH类似物组治疗第8周的子宫系数、子宫白介素(IL)-10与肿瘤坏死因子(TNF)-α表达水平都低于模型组(P<0.05),GnRH类似物组低于米非司酮组(P<0.05)。米非司酮组与GnRH类似物组治疗第8周的子宫内膜厚度、腺间质面积比、腺体面积与腺腔面积都高于模型组(P<0.05),GnRH类似物组高于米非司酮组(P<0.05)。米非司酮组与GnRH类似物组治疗第8周的子宫组织Wnt5b与β-catenin蛋白相对表达水平低于模型组(P<0.05),GnRH类似物组低于米非司酮组(P<0.05)。结论:GnRH类似物在子宫肌瘤大鼠模型的应用能降低子血液黏度,还可抑制血清性激素的分泌,增加子宫系数,抑制Wnt5b与β-catenin蛋白的表达,从而可改善子宫肌瘤大鼠的炎性细胞浸润状态与子宫内膜形态。  相似文献   
27.
This study investigated the involvement of neutrophil infiltration, nitric oxide (NO) generation, and oxidative stress in indomethacin-induced ulcer and the possible gastroprotective potentials of spermine and taurine, known for their tissue regenerating and antioxidant effects, respectively. Male Wistar albino rats (180-220 g) were allocated into a normal control group, ulcer control group (received a single dose of indomethacin 40 mg-kg p.o.), and two ulcer groups pretreated with spermine (150 mg-kg p.o. 1 h before ulcer induction) and taurine (250 mg-kg i.p. for three consecutive days before ulcer induction). The animals were killed 6 h after indomethacin administration, and the gastric juice, serum, and mucosal tissue were used for gastric injury evaluation. Both modulators significantly ameliorated the indomethacin-induced gastric lesions in glandular mucosa. Notably, spermine exhibited the most pronounced effect as manifested by great reduction in the gastric ulcer index, normalization of the elevated gastric acidity, and triggering of mucin production. Spermine and taurine were able to decrease the elevated levels of gastric myeloperoxidase, conjugated diene, and serum NO. However, the lowered tissue NO content was markedly elevated only by taurine. The antioxidant action of taurine was illustrated by restoration of the depressed content of glutathione, normalization of the inhibited activities of glutathione reductase, and superoxide dismutase. These results suggest that spermine and taurine confer significant gastroprotection against indomethacin-induced gastric injury with the priority of spermine.  相似文献   
28.
目的:探究股神经阻滞麻醉联合伤口局部浸润麻醉对老年髋关节置换术后疼痛程度的影响。方法:选择2016年1月~2018年6月我院收治的髋关节置换术的85例患者,据患者入院的编号的奇偶随机分为两组。对照组的42例采用伤口浸润麻醉方法,观察组的43例采用股神经阻滞麻醉联合伤口浸润麻醉方法。比较两组的麻醉效果、镇痛效果、术后阿片类药物的使用情况、住院时间及下床活动时间。结果:观察组感觉阻滞时间、恢复痛觉时间均显著长于对照组(P<0.05),术后12 h的视觉模拟评分法(Visual analog scales,VAS)评分较对照组明显降低(P<0.05),但两组术后6 h和1 d的VAS评分无统计学差异(P>0.05);观察组术后1 d的阿片类药物使用剂量较对照组明显降低(P<0.05),但两组术后2 d的阿片类药物使用剂量比较无统计学差异(P>0.05),观察组住院时间及下床活动时间较对照组明显缩短(P<0.05)。结论:股神经阻滞联合伤口浸润麻醉对于进行髋关节置换术的老年患者具有较好的镇痛效果,且在手术后阿片类镇痛药物的使用剂量减少,住院时间和下床活动时间均有所改善。  相似文献   
29.
青海乐都地区森林涵养水源效能研究   总被引:3,自引:0,他引:3       下载免费PDF全文
 乐都县北山林区有六种主要森林群落类型,通过对其土壤物理性质、枯落物、枯落物水容量、土壤渗透和地下径流的测定分析以及涵养水源效能之估价,指出:该区森林群落土壤具有良好的涵养水源功能,表现为:土壤容重降低,孔隙度的增加,一公顷森林土壤能蓄水641—978t,枯落物的吸水量是它自身重的2.9—7.6倍;土壤的渗透速度远大于本区最大降水强度。  相似文献   
30.
目的:比较关节内与关节周围浸润镇痛对前交叉韧带重建术(ACLR)后患者的镇痛效果。方法:选择2014年1月至2015年11月在我院拟行ACLR的前交叉韧带断裂患者40例,将其随机分为关节内浸润镇痛组(IA组)与关节周围浸润镇痛组(PA组),每组20例。两组均于术前3d定时口服塞来昔布(200mg,bid),术前0.5h行股神经阻滞(3.3g/L罗哌卡因30mL)。术中IA组于关节内给予30mL复合镇痛药物,而PA组于关节周围滑膜内注射相同药物。术后均给予24h冰敷治疗。观察两组患者术后12-72h及出院时的静息与活动疼痛视觉模拟评分(VAS),术后24-72h及出院时膝关节活动度,记录患者术后吗啡用量及不良反应情况。结果:PA组术后12-72h在静息与活动时以及在出院当天的活动时,VAS评分均显著低于IA组(P0.05)。术后24-72hPA组关节活动度均优于IA组(P0.05)。术后IA组、PA组吗啡镇痛使用率分别为30%、15%,且IA组吗啡平均用量为(10.3±1.1)mg,明显高于PA组的(5.4±0.9)mg(P0.05)。两组不良反应率比较差异无统计学意义(P0.05)。结论:关节周围浸润镇痛为主的多模式镇痛对ACLR围手术期患者的镇痛效果更好,更有利于关节功能的康复,值得临床推广应用。  相似文献   
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