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941.
目的通过流行病学调查及临床检查,探讨牙周炎与慢性阻塞性肺疾病(COPD)之间的相关性。方法收集中国医科大学附属第一医院、盛京医院、第四医院和沈阳市第八人民医院2008年10月至2009年4月确诊为COPD的患者266例,其中稳定期COPD患者160例,急性加重期COPD(AE—COPD)患者106例,检查并记录所有患者6颗指数牙(61 6、6 16)的简化1:7腔卫生指数(OHI—S)、龈沟出血指数(SBI)、牙周探诊深度(PD)、临床附着丧失(CAL),同时对所有患者进行肺功能指标的检查,并进行口腔问卷调查。结果(1)AE—COPD组的吸烟率为47.2%,明显高于稳定期COPD组(P〈0.01);(2)AE—COPD组的SBI、PD及CAL明显高于稳定期COPD组(P〈0.01);(3)AE—COPD组的OHI—S、SBI、PD及CAL均与FEVl%呈负相关(r分别为-0.309、-0.333、-0.395、-0.702,均P〈0.01),其中CAL与FEVI%的相关性最强;稳定期COPD组CAL与FEVI%呈负相关(r=-0.657,P〈0.01)。结论(1)吸烟作为牙周炎和COPD的共同危险因素,在牙周炎和COPD的发生和发展中发挥重要作用;(2)AE—COPD患者的牙周炎症程度均随着肺功能的减弱而加重,提示牙周炎与COPD之间存在一定相关性。 相似文献
942.
Role of Akt signaling pathway in delayed cerebral vasospasm after subarachnoid hemorrhage in rats 总被引:1,自引:0,他引:1
Jin-Ning Song Ji-Yang An Guang-Shan Hao Dan-Dong Li Peng Sun Yu Li Jun-Gang Xue 《Acta neurochirurgica》2013,155(11):2063-2070
Background
Akt plays an important role in cell survival, proliferation, apoptosis and other activities. It also has been involved in maintaining smooth muscle cell contraction phenotypes in vitro and in vivo. Recent studies have focused on the inhibition of Akt in acute vasospasm and neuronal apoptosis after subarachnoid hemorrhage (SAH). However, its role in delayed cerebral vasospasm (DCVS) has not been reported.Methods
In this study, using a “two-hemorrhage” rat model of SAH, we examined the expression of p-Akt and the formation of vasospasm in the basilar arteries. To investigate the possible role of Akt in phenotypic switching, we performed immunohistochemical staining to examine expressions of SMα-actin and proliferating cell nuclear antigen (PCNA), markers of smooth muscle phenotypic switching.Results
We found that the basilar arteries exhibited vasospasm after SAH and that vasospasm became most severe on day 7 after SAH. Elevated protein expression of p-Akt was detected 4 days after SAH induction, peaked on day 7, and recovered on day 21, which was in a parallel time course to the development of DCVS. Moreover, results of immunohistochemical staining revealed enhanced expression of PCNA but gradual reduction in expression of SMα-actin from day 1 to day 7 after SAH; then, the expressions of PCNA and SMα-actin gradually recovered until day 21.Conclusions
These results support a novel mechanism in which the Akt signaling pathway plays an important role in the proliferation of smooth muscle cells (SMCs) rather than inducing phenotype switching in basilar arteries, which promotes the development of DCVS after SAH. 相似文献943.
This paper is concerned with the problem of robust fault detection filter design for a class of neutral‐type neural networks with time‐varying discrete and unbounded distributed delays. A Luenberger‐type observer is designed for monitoring fault. By introducing an appropriate Lyapunov–Krasovskii functional and by using Jensen's inequality techniques to deal with its derivative, a new sufficient condition for the existence of robust fault detection filter is proposed in the form of LMIs with nonlinear constraints. To solve the nonlinear problem, a cone complementarity linearization algorithm is proposed. In addition, several numerical examples are provided to illustrate the applicability of the proposed approach. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
944.
Jiahua Pan Qi Chen Wei Xue Yonghui Chen Lei Xia Haige Chen Yiran Huang 《Urological research》2013,41(1):73-78
The aim of the study was to compare the clinical outcome and the cost-effectiveness between retrograde intra renal surgery (RIRS) and mini-percutaneous nephrolithotripsy (mPCNL) for the management of single renal stone of 2–3 cm in Chinese medical setting. From May 2005 to February 2011, 115 patients with solitary renal calculi were treated either by RIRS or mPCNL. 56 patients were in RIRS group while 59 were in mPCNL group. Patients’ demographics between the two groups, in terms of gender, age, BMI, history of ESWL as well as stone side, stone location and stone size were comparable. Peri-operative course, clinical outcome, complication rates and medical cost were compared. The effective quotient (EQ) of two groups was calculated. Data were analyzed using Fisher’s exact test, Chi-square test and Student’s t test. EQ for RIRS and mPCNL were 0.52 and 0.90. The initial stone-free rate (SFR) of RIRS group and mPCNL group was 71.4 and 96.6 %, respectively (P = 0.000). The mean procedure number was 1.18 in RIRS group and 1.03 in mPCNL group, respectively (P = 0.035). The operative time for RIRS was longer (P = 0.000) while the mean hospital stay was shorter (P = 0.000). There was no statistical difference in peri-operative complications between the groups. The initial hospitalization cost, laboratory and radiology test cost of RIRS group were lower (P = 0.000). However, counting the retreatment cost in the two groups, the total medical expenditure including the overall hospitalization cost, overall laboratory and radiology test cost and post-operative out-patient department (OPD) visit cost was similar between two groups. In conclusion, with similar total medical cost, mPCNL achieved faster stone clearance and lower retreatment rate without major complications, which implied higher cost-effectiveness for the treatment of single renal stone of 2–3 cm in Chinese medical setting. RIRS is also a safe and reliable choice for patients having contraindications or preference against mPCNL. 相似文献
945.
Rajpathak SN Xue X Wassertheil-Smoller S Van Horn L Snetselaar L Martin LW Rohan TE 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2012,22(4):337-339
Low-fat diet may play a role in prevention of cardiovascular disease (CVD) by altering the levels of hemostatic factors. There are yet limited data on the effects of low-fat diet on the circulating levels of these factors and existing studies are limited by small sample size and short duration of follow-up. We conducted an analysis in a subset of women (active arm = 723; control arm = 1036) within the Women's Health Initiative Dietary Modification Trial to investigate the long term effect of a low-fat diet on circulating levels of fibrinogen, factor VII concentration and factor VII activity among postmenopausal women aged 50-79 years. Using linear mixed effects model with random intercept and data from three follow-up visits (years 1, 3 and 6) we evaluated the change in each factor over time. Overall, the changes in these factors were small (less than 5%) in both the arms of the trials at the end of intervention and there was no significant difference in mean change between the two arms. Our results indicate that the low-fat dietary intervention was not associated with significant changes in hemostatic factors among postmenopausal women. 相似文献
946.
947.
Zhao H Bai X Nie XH Wang JT Wang XX Pang NN Li YJ Ma XM Wen H Ding JB 《中国寄生虫学与寄生虫病杂志》2012,30(1):32-35
目的观察泡球蚴感染小鼠肝脏中白细胞介素-10(IL-10)和转化生长因子-β(TGF-β1)的动态变化。方法将60只雌性BALB/c小鼠随机均分为实验组和对照组,实验组腹腔注射活原头节悬液0.2ml(约含400个原头节),对照组腹腔注射等量生理盐水,分别于接种后2、8、30、90、180和360d各处死5只小鼠,取肝组织进行病理学检查,并用免疫组织化学法检测肝组织中IL-10和TGF-β1的表达情况。结果实验组小鼠,腹腔和肝小叶出现多处直径不等的小囊泡,随感染时间的延长逐渐增多增大,与周围肝组织分界不明显。HE染色显示,实验组小鼠肝脏出现炎症细胞浸润,泡球蚴纤维囊壁与肝细胞和囊壁之间炎症反应带的形成等不同程度的病理改变;对照组小鼠肝小叶结构完整,偶见少量炎症细胞浸润,肝细胞胞浆疏松化和脂肪变性。实验组小鼠肝组织表达水平随着泡球蚴感染时间的延长而逐渐上升,感染后90d,实验组小鼠肝组织中IL-10和TCF-β1的表达水平均达高峰,细胞阳性率分别为(16.39±1.73)%和(23.69±2.29)%,与对照组比较[(1.09±0.10)%和(0.98±0.09)%]差异均有统计学意义(P<0.01),而且之后均维持在较高水平。结论小鼠泡球蚴感染中晚期,IL-10和TGF-β1表达水平均提高,其免疫抑制作用不利于清除和控制肝脏中泡球蚴。 相似文献
948.
949.
目的探讨导管消融治疗房性早搏(PACs)的临床疗效。方法 10例PACs病人,Holter提示24 h PACs17 957.2±4 532个,4例伴有短阵房性心动过速,根据心内激动顺序,初步确定感兴趣区域,应用激动标测法进行标测,在相对最提前部位消融,采用标准为提前≥30 ms。结果手术时间1.6±0.6 h,X线曝光时间21.6±5.4min。每例病人消融2.8±0.8(2~5)次。术后第3日Holter检查,5例病人PACs完全消失,3例病人PACs在2~12个之间,2例病人PACs分别为307及204个,此2例术前均为双源性PACs,残余均为另外一种形态的PACs。随访9.3±4.2个月,无1例复发。结论导管消融治疗PACs是安全和有效的。 相似文献
950.
Hua-Rong Tang Xian-Qin Luo Gang Xu Yan Wang Zhi-Jun Feng Hui Xu Ya-Wei Shi Qin Zhang Li-Guang Wu Chun-Quan Xue Cheng-Wei Wang Chao-Yang Wu 《World journal of gastroenterology : WJG》2012,18(48):7319-7326
AIM:To elucidate high mobility group-box 3(HMGB3) protein expression in gastric adenocarcinoma,its potential prognostic relevance,and possible mechanism of action.METHODS:Ninety-two patients with gastric adenocarcinomas surgically removed entered the study.HMGB3 expression was determined by immunohistochemistry through a tissue microarray procedure.The clinicopathologic characteristics of all patients were recorded,and regular follow-up was made for all patients.The inter-relationship of HMGB3 expression with histological and clinical factors was analyzed using nonparametric tests.Survival analysis was carried out by Kaplan-Meier(log-rank) and multivariate Cox(Forward LR) analyses between the group with overexpression of HMGB3 and the group with low or no HMGB3 ex-pression to determine the prognosis value of HMGB3 expression on overall survival.Further,HMGB3 expression was knocked down by small hairpin RNAs(shRNAs) in the human gastric cancer cell line BGC823 to observe its influence on cell biological characteristics.The MTT method was utilized to detect gastric cancer cell proliferation changes,and cell cycle distribution was analyzed by flow cytometry.RESULTS:Among 92 patients with gastric adenocarcinomas surgically removed in this study,high HMGB3 protein expression was detected in the gastric adenocarcinoma tissues vs peritumoral tissues(P 0.001).Further correlation analysis with patients' clinical and histology variables revealed that HMGB3 overexpression was obviously associated with extensive wall penetration(P = 0.005),a positive nodal status(P = 0.004),and advanced tumor-node-metastasis(TNM) stage(P = 0.001).But there was no correlation between HMGB3 overexpression and the age and gender of the patient,tumor localization or histologic grade.Statistical Kaplan-Meier survival analysis disclosed significant differences in overall survival between the HMGB3 overexpression group and the HMGB3 no or low expression group(P = 0.006).The expected overall survival time was 31.00 ± 3.773 mo(95%CI = 23.605-38.395) for patients with HMGB3 overexpression and 49.074 ± 3.648 mo(95%CI = 41.925-57.311) for patients with HMGB3 no and low-level expression.Additionally,older age(P = 0.040),extensive wall penetration(P = 0.008),positive lymph node metastasis(P = 0.005),and advanced TNM tumor stage(P = 0.007) showed negative correlation with overall survival.Multivariate Cox regression analysis indicated that HMGB3 overexpression was an independent variable with respect to age,gender,histologic grade,extent of wall penetration,lymph nodal metastasis,and TNM stage for patients with resectable gastric adenocarcinomas with poor prognosis(hazard ratio = 2.791,95%CI = 1.233-6.319,P = 0.019).In the gene function study,after HMGB3 was knocked down in the gastric cell line BGC823 by shRNA,the cell proliferation rate was reduced at 24 h,48 h and 72 h.Compared to BGC823 shRNA-negative control(NC) cells,the cell proliferation rate in cells that had HMGB3 shRNA transfected was significantly decreased(P 0.01).Finally,cell cycle analysis by FACS showed that BGC823 cells that had HMGB3 knocked down were blocked in G1/G0 phase.The percentage of cells in G1/G0 phase in BGC823 cells with shRNA-NC and with shRNA-HMGB3 was 46.84% ± 1.7%,and 73.03% ± 3.51% respectively(P = 0.001),whereas G2/M cells percentage decreased from 26.51% ± 0.83% to 17.8% ± 2.26%.CONCLUSION:HMGB3 is likely to be a useful prognostic marker involved in gastric cancer disease onset and progression by regulating the cell cycle. 相似文献