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991.
Na Liu Xiangjie Li Ning Liu Lijun Ye Jianping An Xin Nie Luchuan Liu Manjing Deng 《Clinical oral investigations》2013,17(3):999-1007
Objectives
This study aimed to investigate the root canal morphology of mandibular first premolar teeth in a population from southwestern China by micro-computed tomography (micro-CT).Materials and methods
Human mandibular first premolars (115) were selected and prepared for micro-CT analysis with a slice thickness of 30 μm. Details of root canal orifices, canals, accessory canals, apical foramina–apical delta intercanal communication, loops and isthmuses, and mesial invagination were analyzed from reconstructed three-dimensional (3D) images.Results
Canal patterns categorized according to the classification defined by Vertucci (Endod Top 10:3–29, 2005) as types I (65.2 %), III (2.6 %), V (22.6 %), and VII were identified (0.9 %). Accessory canals were present in 35.7 % of the samples and were predominantly located in the apical third of the root. A single apical foramen was observed in 50.4 % of the samples and two or three foramina in 28.7 % and 14.8 %, respectively. Apical delta was identified in 6.1 % of the samples and the prevalence of intercanal communication and loops was 3.5 % and 7 %, respectively. Mesial invagination of the root was identified in 27.8 % of the samples, the majority of which contained multiple canals.Conclusions
The data obtained in this study revealed complex root morphology with high prevalence of multiple canals, more than half of which exhibited type I canal patterns.Clinical relevance
Micro-CT was used as a noninvasive technique for 3D investigation of root canal morphology in the mandibular first premolars of a population from southwestern China. Furthermore, data obtained revealed complex anatomy of various types. 相似文献992.
目的总结与评价应用不同类型附着体的种植覆盖义齿的临床效果。方法对28例无牙颌患者分别采用种植体支持的磁附着体、杆卡式、套筒冠、球帽式覆盖义齿随访及效果进行对比评价。观察随访,定期拍摄X线片及口腔检查,观察种植体骨吸收和软组织状况,并对使用4种类型覆盖义齿的患者进行满意度调查和并发症分析。结果除1例磁附着体覆盖义齿患者发生3枚种植体脱落现象外,其余种植体均稳定。不同类型附着体种植覆盖义齿的骨吸收量、牙龈指数和满意度评价的差异均无统计学意义﹙P>0.05﹚;患者戴牙前后的义齿总体满意度、义齿固位及稳定情况、咀嚼效率、舒适度方面有明显的改善(P<0.05﹚。结论各类种植体支持的覆盖义齿稳定舒适,咀嚼功能增强,患者对满意度有较高的评价,提高了无牙颌患者的生存质量。 相似文献
993.
Yi Zhang Ben Zhou Bo Deng Fang Zhang Jingxia Wu Yuangao Wang Yingying Le Qiwei Zhai 《Diabetes》2013,62(4):1159-1166
Amyloid-β (Aβ), a natural product of cell metabolism, plays a key role in the pathogenesis of Alzheimer’s disease (AD). Epidemiological studies indicate patients with AD have an increased risk of developing type 2 diabetes mellitus (T2DM). Aβ can induce insulin resistance in cultured hepatocytes by activating the JAK2/STAT3/SOCS-1 signaling pathway. Amyloid precursor protein and presenilin 1 double-transgenic AD mouse models with increased circulating Aβ level show impaired glucose/insulin tolerance and hepatic insulin resistance. However, whether Aβ induces hepatic insulin resistance in vivo is still unclear. Here we show C57BL/6J mice intraperitoneally injected with Aβ42 exhibit increased fasting blood glucose level, impaired insulin tolerance, and hepatic insulin signaling. Moreover, the APPswe/PSEN1dE9 AD model mice intraperitoneally injected with anti-Aβ neutralizing antibodies show decreased fasting blood glucose level and improved insulin sensitivity. Injection of Aβ42 activates hepatic JAK2/STAT3/SOCS-1 signaling, and neutralization of Aβ in APPswe/PSEN1dE9 mice inhibits liver JAK2/STAT3/SOCS-1 signaling. Furthermore, knockdown of hepatic JAK2 by tail vein injection of adenovirus inhibits JAK2/STAT3/SOCS-1 signaling and improves glucose/insulin tolerance and hepatic insulin sensitivity in APPswe/PSEN1dE9 mice. Our results demonstrate that Aβ induces hepatic insulin resistance in vivo via JAK2, suggesting that inhibition of Aβ signaling is a new strategy toward resolving insulin resistance and T2DM.More than 250 million people worldwide were diagnosed with type 2 diabetes mellitus (T2DM) in 2011, and this number is expected to double within the next 20 years (1). Insulin resistance is a key element in the pathogenesis of T2DM, defined as a state of reduced responsiveness to normal circulating levels of insulin in insulin-target liver, skeletal muscle, and adipose tissues (2). Many states give rise to insulin resistance, and all are explained by numerous mechanisms in which insulin signaling is decreased (3). Interestingly, it has been reported that brains from Alzheimer’s disease (AD) patients display impaired insulin signaling (4,5), and some AD patients exhibit impaired glucose metabolism and hyperinsulinemia (6,7). Furthermore, an epidemiological study indicates patients with AD have an increased risk of developing T2DM (8), and experimental studies demonstrate AD model mice also exhibit diabetic phenotype (9,10). These studies together reveal a strong correlation between AD and insulin resistance/T2DM.Amyloid-β (Aβ) is a natural product during cell metabolism and originates from proteolysis of the amyloid precursor protein (APP) by the sequential enzymatic actions of β-site amyloid precursor protein–cleaving enzyme 1 (BACE-1) and γ-secretase (11). According to the amyloid cascade hypothesis, Aβ has an early and vital role in the pathogenesis of AD (11,12). In the central nervous system, Aβ has been reported to impair neuronal synaptic function in early AD by compromising insulin signaling (13–16). Interestingly, Aβ can be detected in the peripheral circulation and tissues (17–19).We have previously reported that Aβ induces insulin resistance in cultured hepatocytes mainly through the JAK2/STAT3/SOCS-1 signaling pathway (10), indicating that Aβ is an inducer of insulin resistance in vitro. On the other hand, animal studies demonstrate that the crossbred mice of APP23 transgenic AD model mice and ob/ob mice showed an accelerated diabetic phenotype (20). Moreover, APPswe/PS1(A246E) transgenic AD model mice with increased plasma Aβ42 level exhibit impaired glucose tolerance when fed a chow diet (9,21). Consistently, we have recently reported that APPswe/PSEN1dE9 (APP/PS1) transgenic AD model mice with increased plasma Aβ40/42 levels show impaired glucose/insulin tolerance and hepatic insulin signaling, hyperinsulinemia, and upregulation of SOCS-1 and phosphorylated JAK2 and STAT3 in the liver (10). However, it is still possible that the insulin resistance in AD model mice might be due to the overexpression of presenilin 1, APP, and/or APP cleavage products except Aβ. Thus, whether Aβ itself can induce insulin resistance in vivo is yet to be elucidated. In addition, we previously showed that Aβ induces insulin resistance by activating the JAK2/STAT3/SOCS-1 signaling pathway in cultured hepatocytes (10). Whether Aβ also induces hepatic insulin resistance in vivo by activating the JAK2/STAT3/SOCS-1 signaling pathway is still unclear.In this study, we investigated the effect of Aβ on insulin sensitivity in vivo by injection of Aβ42 into wild-type mice and injection of Aβ-neutralizing antibodies or adenovirus expressing JAK2 small interfering (si)RNA into APP/PS1 AD model mice. We found that injection of Aβ42 into C57BL/6J mice induces insulin resistance and activates hepatic JAK2/STAT3/SOCS-1 signaling. Moreover, APP/PS1 mice treated with anti–Aβ-neutralizing antibodies show improved insulin sensitivity and attenuated hepatic JAK2/STAT3/SOCS-1 signaling. Furthermore, knockdown of hepatic JAK2 by adenovirus inhibited JAK2/STAT3/SOCS-1 signaling and improved insulin sensitivity in APP/PS1 mice. 相似文献
994.
Objective
This study aimed to use amniotic fluid stem cells of donors to induce immune tolerance of heterogenous rat kidney graft for investigating the formation mechanism of immune tolerance.Methods
With Wistar rats as donors and Sprague-Dawley (SD) rats as receptors, the heterogenous kidney graft animal model was established, and amniotic fluid stem cells of Wistar rats were isolated and cultured. Moreover, 40 SD rats were randomly divided into 4 groups. Creatinine (Cr), blood urea nitrogen (BUN), interleukin (IL) 2, interferon (IFN) γ, and oxidative stress levels in serum were detected, flow cytometry was used to detect changes of CD4 and CD8 cells, and quantitative changes of urinary protein and pathologic changes of transplanted kidney were observed.Results
BUN, Cr, IL-2, IFN-γ, and oxidative stress levels and urinary protein quantity in rat serum of the test group were significantly lower than those of the control group, creatinine clearance rate was significantly higher than that of the control group, and renal pathologic injury extent was significantly milder than that of the control group.Conclusions
Amniotic fluid stem cells can induce immune tolerance of rat kidney graft and inhibit oxidative stress level, improve kidney function, and alleviate kidney injury. 相似文献995.
Antithrombin is a plasma protein critical to the regulation of coagulation. It plays a pivotal anticoagulant role by preventing the activation of procoagulant proteinases. Inherited and (or) acquired deficiency of AT is an established risk factor for venous thromboembolism. Sequencing analysis of SERPINC1 gene of three families revealed that Family I had double novel missense mutations (c.134G > A&c.342T > G), Family II had a nonsense mutation (c.770G > A) while Family III had a frameshift mutation (c.800-803del). In addition, all of them had a large number of carriers in their families what was very rare in China. 相似文献
996.
997.
Mao YH Hu WC Tu J Chen FJ Wan RF Ning A Zhang B Chen Z Li M Zhang BY Zou JX Deng Q 《中国血吸虫病防治杂志》2012,24(2):203-4, 211
目的掌握新建县晚期血吸虫病患者治疗救助情况。方法收集2005-2009年新建县晚期血吸虫病患者治疗救助数据,采用《江西省晚期血吸虫病人治疗救助信息管理系统》录入并统计。结果 636例患者中,男女性别比1.19∶1,平均年龄61.52±11.2岁。患者以腹水型为主,占93.71%,其中切脾术后患者占32.38%,IHA阳性率31.6%,HBsAg阳性率24.37%,复治率44.50%,临床治愈率43.53%,好转率55.94%,病死率5.97%。结论晚期血吸虫病治疗救助取得了改善患者症状、缓解病情和提高生活质量的效果。 相似文献
998.
Diao TJ Chen X Deng LH Chen HX Liang Y Zhao XD Wang QH Yuan WS Gao BC Ye Y 《World journal of gastroenterology : WJG》2012,18(25):3310-3316
AIM: To evaluate immunological protection of nitric oxide (NO) in hepatopulmonary syndrome and probable mechanisms of ischemia-reperfusion (IR) injury in rat liver transplantation.METHODS: Sixty-six healthy male Wistar rats were randomly divided into three groups (11 donor/recipient pairs). In group II, organ preservation solution was lactated Ringer’s solution with heparin 10 000/μL at 4 °C. In groups I and III, the preservation solution added, respectively, L-arginine or NG-L-arginine methyl ester (L-NAME) (1 mmol/L) based on group II, and recipients were injected with L-arginine or L-NAME (50 mg/kg) in the anhepatic phase. Grafted livers in each group were stored for 6 h and implanted into recipients. Five rats were used for observation of postoperative survival in each group. The other six rats in each group were used to obtain tissue samples, and executed at 3 h and 24 h after transplantation. The levels of alanine aminotransferase (ALT), tumor necrosis factor (TNF)-α and NO metabolites (NOx) were detected, and expression of NO synthase, TNF-α and intercellular adhesion molecule 1 (ICAM-1) was examined by triphosphopyridine nucleotide diaphorase histochemical and immunohistochemical staining.RESULTS: By supplementing L-arginine to strengthen the NO pathway, a high survival rate was achieved and hepatic function was improved. One-week survival rate of grafted liver recipients in group I was significantly increased (28.8 ± 36.6 d vs 4 ± 1.7 d, P < 0.01) as compared with groups II and III. Serum levels of ALT in group I were 2-7 times less than those in groups II and III (P < 0.01). The cyclic guanosine monophosphate (cGMP) levels in liver tissue and NOx in group I were 3-4 times higher than those of group II after 3 h and 24 h reperfusion, while in group III, they were significantly reduced as compared with those in group II (P < 0.01). The levels of TNF-α in group I were significantly lower than in group II after 3 h and 24 h reperfusion (P < 0.01), while being significantly higher in group III than group II (P < 0.01). Histopathology revealed more severe tissue damage in graft liver and lung tissues, and a more severe inflammatory response of the recipient after using NO synthase inhibitor, while the pathological damage to grafted liver and the recipient’s lung tissues was significantly reduced in group I after 3 h and 24 h reperfusion. A small amount of constitutive NO synthase (cNOS) was expressed in liver endothelial cells after 6 h cold storage, but there was no expression of inducible NO synthase (iNOS). Expression of cNOS was particularly significant in vascular endothelial cells and liver cells at 3 h and 24 h after reperfusion in group II, but expression of iNOS and ICAM-1 was low in group I. There was diffuse strong expression of ICAM-1 and TNF-α in group III at 3 h after reperfusion.CONCLUSION: The NO/cGMP pathway may be critical in successful organ transplantation, especially in treating hepatopulmonary syndrome during cold IR injury in rat orthotopic liver transplantation. 相似文献
999.
背景:粪便钙卫蛋白(FC)对鉴别诊断肠道炎症性疾病有较高的临床价值,但其在全消化系统疾病中的意义尚不完全清楚。目的:探讨FC在全消化系统疾病鉴别诊断中的意义。方法:纳入2011年6~8月南京军区南京总医院溃疡性结肠炎、克罗恩病、结肠息肉、肠易激综合征、食管炎、食管息肉、慢性胃炎、胃、十二指肠溃疡、急性胰腺炎、胃淋巴瘤患者共47例,以12名健康人作为对照,采用ELISA方法测定FC水平。以受试者工作特征(ROC)曲线分析FC检测的诊断效能。结果:在下消化道疾病中,溃疡性结肠炎和克罗恩病患者的FC水平显著高于结肠息肉和肠易激综合征患者(P〈0.01).FC检测鉴别这两组疾病的ROC曲线下面积为0.952。食管炎、食管息肉、胃淋巴瘤患者的FC水平显著高于慢性胃炎、胃、十二指肠溃疡、急性胰腺炎患者(P〈0.01)。结论:FC作为一种非侵入性检测方法,对消化系统疾病的鉴别诊断具有一定临床价值。 相似文献
1000.
目的 总结IgG4相关性疾病临床特征及预后,提高认识,做到早期诊断及合理治疗.方法 对在我院住院明确诊断的20例IgG4相关性疾病患者资料进行回顾性分析.结果 20例患者中男性14例,女性6例,平均年龄58岁,胰腺和胆管为最常见受累器官,17例患者(85%)有≥2个器官受累.所有患者血清IgG4均明显升高(>1350 mg/L).12例患者行组织病理学检查,主要表现为组织弥漫性纤维化,伴有大量淋巴细胞、浆细胞浸润,免疫组织化学可见CD38阳性浆细胞浸润,IgG4阳性浆细胞浸润,IgG4阳性浆细胞占IgG阳性浆细胞比例均>40%.20例患者中,除1例患者死于急性化脓性胆管炎及1例未治疗,其余患者病情均明显缓解.结论 IgG4相关性疾病临床症状无特异性,血清IgG4可作为疑似病例的首选检查方法,及时应用糖皮质激素可迅速缓解病情. 相似文献