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931.
932.
Jie Xu Li Gao Hongbing Yao Rong Zhang Na Liu Lijia Wang 《The Journal of asthma》2013,50(11):1187-1196
Objective: This study aims to establish an experimental mouse model of minimal persistent inflammation (MPI), observe the features of inflammation and hyper-responsiveness of the upper/lower airways, and explore the relationship between inflammation and hyper-responsiveness in the upper/lower airways. Methods: Sixty-four female BALB/c mice were randomly divided into four groups: allergic rhinitis (AR) group as positive control, MPI group, negative control group and blank control group. Mice were given high and low-concentrated ovalbumin solution after basic and intensive sensitization to establish AR model and MPI model. Nasal mucosa and lung tissues were stained to observe eosinophil infiltration, goblet cell hyperplasia, and expression of intercellular adhesion molecule 1 (ICAM-1). Airway hyper-responsiveness was assessed. Levels of specific immunoglobulin E (sIgE), interleukin (IL)-4 and IL-5 in peripheral blood, nasal lavage fluid (NLF), and bronchoalveolar lavage fluid (BALF) were detected by Enzyme-linked immunosorbent assay. Results: The eosinophil infiltration and expression of ICAM-1 on nasal mucosa and in lung tissues in the AR and MPI groups were significantly elevated compared to control groups. Goblet cells count increased only in the nasal mucosa and not in lung tissues. Eosinophil and neutrophil count of NLF and BALF in the AR and MPI groups increased significantly compared to control groups. Level of IL-4 did not increase significantly, but sIgE and IL-5 did. Conclusions: Mice in the MPI status exhibits lower airway inflammation and hyper-responsiveness with increase in eosinophil count, goblet cells, ICAM-1, IL-4, and IL-5. These results provide further evidence for the importance of MPI of AR in lower airway diseases. 相似文献
933.
934.
目的观察心复康丸对压力超负荷性心肌肥厚大鼠超声心动指标及心肌肥厚程度的影响。方法 Wistar雄性大鼠采用腹主动脉缩窄的方法复制心肌肥厚和心室重构的模型。造模4周后,随机分为假手术组(S组)、模型组(M组)、依那普利组(E组)、心复康丸低剂量组(L组)、心复康丸高剂量组(H组)。分别于术后8周、12周采用超声心动评价心功能,并观察心脏肥大指数变化。结果术后8周,M组大鼠出现压力超负荷介导的向心性肥厚,术后12周,M组大鼠心功能进入失代偿期,E组和H组大鼠上述病理性改变均能被抑制;此两组还具有降低心脏肥大指数的作用(P0.01)。结论心复康丸具有改善超声心动指标,延缓心肌肥厚的作用,并存在一定量效关系。 相似文献
935.
目的观察食管鳞癌组织中核转录因子-κB(NF-κB)p50、细胞间黏附分子-1(ICAM-1)、基质金属蛋白酶-9(MMP-9)的表达变化,并探讨其临床意义。方法选择食管鳞癌组织标本49例(鳞癌组)、癌旁不典型增生组织标本33例(癌旁组)、正常食管黏膜组织标本32例(正常组),采用免疫组化S-P法检测各组NF-κB p50、ICAM-1、MMP-9的表达,分析各指标间的相关性及与食管鳞癌临床病理特征的关系。结果鳞癌组、癌旁组、正常组NF-κB p50阳性率分别为55.1%、51.5%、28.1%,ICAM-1阳性率分别为42.9%、0.0%、0.0%,MMP-9阳性率分别为71.4%、51.5%、34.4%。鳞癌组与正常组NF-κB p50、ICAM-1、MMP-9比较差异均有统计学意义(χ2=5.706,P=0.017;χ2=18.514,P<0.001;χ2=10.831,P=0.001)。NF-κBp50表达与食管鳞癌组织分化程度、浸润深度有关(P均<0.05),ICAM-1、MMP-9表达与食管鳞癌组织分化程度、浸润深度和淋巴结转移有关(P均<0.05);NF-κB p50与ICAM-1、MMP-9在食管鳞癌组织中表达均呈正相关(r=0.533,P<0.001;r=0.337,P=0.018)。结论 NF-κB p50、ICAM-1及MMP-9在食管鳞癌发生、发展过程中起重要作用,三者联合检测对食管鳞癌的预后判断具有重要意义。 相似文献
936.
937.
目的 对响水县县城已婚妇女腹部超声普查结果回顾性分析,讨论妇女疾病的阳性率,对以后的保健及治疗提供依据.方法 对2010-10-2012-04来我院体检的2 046例妇科超声体检资料中检出的多例妇科疾病进行回顾性分析.结果 子宫肌瘤发病最多,其次是卵巢囊肿.结论 超声检查在健康普查中是一项非常重要的检测手段,具有简便易行,准确率高,可重复检查等特点,且能清晰显示内脏器官,在妇科的检查中已经承担起举足轻重的作用. 相似文献
938.
Nonsmall cell lung cancer (NSCLC) is the most common type of lung cancer and remains the deadliest form of cancer in the United States and worldwide. New therapies are highly sought after to improve outcome. The effect of sodium-R-alpha lipoate on camptothecin- and paclitaxel-induced cytotoxicity was evaluated on A549 NSCLC and BEAS-2B “normal” lung epithelial cells. Combination indices (CI) and dose reduction indices (DRI) were investigated by studying the cytotoxicity of sodium-R-alpha lipoate (0–16 mM), camptothecin (0–25 nM) and paclitaxel (0–0.06 nM) alone and in combination. 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium-bromide (MTT) was used to assess cytotoxicity. The combinational cytotoxic effects of sodium-R-alpha lipoate with camptothecin or paclitaxel were analyzed using a simulation of dose effects (CompuSyn® 3.01). The effects of sodium-R-alpha lipoate on camptothecin- and paclitaxel-induced cytotoxicity varied based on concentrations and treatment times. It was found that sodium-R-alpha lipoate wasn't cytotoxic toward BEAS-2B cells at any of the concentrations tested. For A549 cells, CIs [(additive (CI = 1); synergistic (CI < 1); antagonistic (CI < 1)] were lower and DRIs were higher for the camptothecin/sodium-R-alpha-lipoate combination (CI = ~0.17–1.5; DRI = ~2.2–22.6) than the paclitaxel/sodium-R-alpha-lipoate combination (CI = ~0.8–9.9; DRI = ~0.10–5.8) suggesting that the camptothecin regimen was synergistic and that the addition of sodium-R-alpha lipoate was important for reducing the camptothecin dose and potential for adverse effects. 相似文献
939.
目的 研究模拟高原低氧条件下兔牙周炎的病理改变以及与破骨细胞相关的核因子κB受体活化子配体( receptor activator of nuclear factor-κB ligand,RANKL)、骨保护素(osteoprotegenn,OPG)的相关性.方法 40只家兔完全随机分成4组:平原实验组、平原对照组、高原实验组、高原对照组,每组各10只.通过钢丝结扎切牙方法建立家兔牙周炎模型,动物于分组饲养8周后处死,制作牙周组织石蜡切片,HE染色观察牙周组织病理变化、破骨细胞的表达,荧光免疫组化检测牙周组织中RANKL、OPG的表达.免疫荧光组化采用激光扫描共聚焦显微镜对实验组与对照组RANKL、OPG进行半定量分析,并比较其差异.结果 高原实验组与平原实验组、高原对照组和平原对照组RANKL灰度值分别为(1.799±0.036)、(1.519±0.061)、(1.242 ±0.078)、(0.963±0.098),差异有统计学意义(P<0.05),与高原对照组比较,高原实验组OPG表达降低无统计学意义.高原实验组RANKL与牙周指数呈正相关(P<0.01).结论 高原低氧条件下可能通过改变破骨细胞的RANKL/OPG调节途径促进牙周炎的发生、发展. 相似文献
940.
A novel anomaly detection method incorporating target information derived from hyperspectral imagery
Anomaly detection is an active research topic in hyperspectral remote sensing and has been applied in many areas including environmental monitoring, urban survey, mineral mapping, and national security. Usually, it makes a detection decision without any prior target information or background information. Several anomaly detection algorithms (e.g. Reed–Xiaoli detector, blocked adaptive computationally efficient outlier nominator and random-selection-based anomaly detector) have been developed, which rely on estimating background information only from a hyperspectral image without considering target information in making a detection decision. These methods may be efficient in general but sometimes with high false alarm rate (FAR). In order to reduce FAR, this study proposes a novel method that incorporates both background and target information, derived from the hyperspectral imagery, into anomaly detection algorithms. The target information is helpful to detect anomalies as outliers. With a scene of real airborne visible infrared imaging spectrometer data, the experimental results demonstrate that the proposed method has produced better detection results and higher time efficiency compared with those using the traditional algorithms that only consider background information. 相似文献