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991.
目的:了解通用型F iltekTMZ350(Z350)和流动型F iltekTMZ350(F350)间的黏结强度。方法:将F350和Z350按照两两组合制备成10 mm×1 mm×1 mm的标准试件,每个试件只有一个位于中间的固化界面,分别为F350和Z350(A组),F350和F350(B组),Z350和Z350(C组)。所有试件在万能试验机上测量微拉伸强度并在体视显微镜下观察试件断裂方式。结果:A组的微拉伸强度明显小于B组和C组(P<0.05),断裂方式以界面断裂为主,而B组和C组之间差异无统计学意义(P>0.05)。结论:使用流动树脂会降低复合树脂固化后层间的结合强度。 相似文献
992.
Aggarwal V Jain A Kabi D 《Australian endodontic journal : the journal of the Australian Society of Endodontology Inc》2011,37(2):61-64
During endodontic therapy various irrigating solutions at different concentrations and duration are used. These chemical solutions may affect the setting reaction of mineral trioxide aggregate (MTA). The aim of this study was to evaluate the effect of sodium hypochlorite (NaOCl) (5.25%), chlorhexidine gluconate (CHX) (2%), ethylenediaminetetraacetic acid (EDTA) solution (17%) and BioPure MTAD on surface micro-hardness and flexural strength of white MTA. Twenty-five disk-shaped and 25 bar-shaped specimens were divided into five groups and were stored under distilled water, NaOCl (5.25%), chlorhexidine CHX (2%), EDTA solution (17%) and BioPure MTAD for 7 days. The micro-hardness of disk specimens was measured while the flexural strength was tested on bar specimens. EDTA and BioPure MTAD significantly reduced the hardness and flexural strength as compared with other groups. Under distilled water strength remained high; therefore, a final flush with distilled water before placement of MTA is advocated, especially if decalcifying agents are used during the clinical procedure. 相似文献
993.
Objectives: The purpose of this study was to histologically examine the responses of intramembraneous bone to calcium sulfate (CaS) and evaluate the resorption and replacement process. Material and methods: Fourteen rabbits were used in this study. Defect healing without any filling material was compared with CaS. Five millimetres wide and 4 mm deep defects were drilled with a trephine bur on both sides of the edentulous space between the incisors and the molars. Test vs. control sites were randomly selected and thereby compared in each animal. The animals were killed after 2, 4 and 8 weeks for histological examination. Results: After 2 weeks, the specimens showed a great extent of degradation of CaS. No signs of the material could be seen after 4 and 8 weeks. There were no statistically significant differences in bone regeneration between the test and control sites within the 8 weeks group in this study. However, there was tendency of more blood vessels in the test sites after 4 weeks of healing. Conclusion: The present study showed that CaS does not interfere with intramembraneous bone healing. In this animal model, the CaS exhibited resorption/degradation early in the healing process while seemingly stimulating angiogenesis. However, there was no significant increase in bone regeneration in the sites treated with CaS during an 8 week period of healing and observation time, as compared with a control defect. To cite this article: Dasmah A, Sennerby L, Rasmusson L, Hallman M. Intramembraneous bone tissue responses to calcium sulfate: an experimental study in the rabbit maxilla.Clin. Oral Impl. Res. xx , 2011; 000–000.doi: 10.1111/j.1600‐0501.2010.02129.x 相似文献
994.
目的探讨微量泵静脉注射与传统人工手推静脉注射胺碘酮的不良反应。方法选择在本院注射胺碘酮治疗的患者160例,随机分为微量泵注射组和传统静脉注射组各80例。两组注射时间均为8min,胺碘酮剂量100mg,推注后观察30min,并于24h观察记录其他不良反应。结果160例接受胺碘酮注射的患者共有34例(21.25%)出现不良反应,其中胺碘酮微量泵静脉注射组(观察组)12例(7.5%),传统静脉注射组(对照组)22例(13.75%)。出现的不良反应有静脉炎、胃肠道不良反应、窦性心动过缓、肝脏不良反应、低血压以及肺部不良反应。两组总不良反应例数有统计学意义(P〈0.05)。结论胺碘酮微量泵与传统静脉注射比较,可以明显减少不良反应的发生率。 相似文献
995.
目的 探讨椎-基底动脉标本设计与制作方法.方法 应用经甲醛溶液防腐处理的标本经颈总动脉插管行乳胶灌注并大体解剖.结果 通过标本灌注与头颈部前外侧解剖层次清晰,充分显示了颈部及颅内主要神经血管的走行和支配范围,逐层显示颈总动脉、颈内动脉、迷走神经、椎动脉全程及基底动脉与基底动脉分支.结论 该方法为临床应用解剖教学与科研提供较好的技术方法. 相似文献
996.
Kobayashi M Hosaka T Ikeda K Seko Y Kawamura Y Sezaki H Akuta N Suzuki F Suzuki Y Saitoh S Arase Y Kumada H 《Hepatology research》2011,41(11):1036-1045
Aim: The micro‐total analysis system (µTAS), a fully automated immunoassay system using microchip capillary electrophoresis, is highly sensitive and able to quickly assay the AFP‐L3%. The clinical usefulness of this system was studied. Methods: We retrospectively enrolled 250 patients who underwent curative treatment for primary hepatocellular carcinoma (HCC) (93 patients underwent hepatic resection and 157, radiofrequency ablation [RFA]). Results: The sensitivity for µTAS AFP‐L3% was 40.3% at the cutoff value of 5% in a range of AFP less than 20 ng/mL where the conventional method was unable to determine AFP‐L3%. The sensitivity for AFP‐L3% remained high even at stage I and at tumor size less than 2 cm (42.5% and 46.0%, respectively). Recurrence rate of patients with AFP‐L3% greater than 5% was significantly higher than that of patients with less than 5% (P = 0.001). Furthermore, in resected patients, the postoperative AFP‐L3% remained elevated with value greater than 5% was related to HCC recurrence (P = 0.001). Multivariate analysis revealed that multiple tumors (P = 0.004), preoperative AFP‐L3% greater than 5% (P = 0.003), albumin less than 3.5 g/dL (P = 0.008), and RFA (P = 0.003) were significant prognostic factors of recurrence. Conclusions: The µTAS was found to be a highly sensitive assay for AFP‐L3% in patients with curative treatment of HCC. A cutoff value of 5% was useful for predicting recurrence after the curative treatment and detecting small tumors and early stage HCC. Additionally, postoperative AFP‐L3% was found to be a prognostic factor of HCC recurrence. 相似文献
997.
Aaron Lechtig Reynaldo Martorell Hernan Delgado Charles Yarbrough Robert E. Klein 《Ecology of food and nutrition》2013,52(4):225-233
The high prevalence of low birth weight (≤ 2.5 Kg) babies is a major public health problem in many poor communities. Studies in humans suggest that malnutrition during pregnancy is an important factor in accounting for this problem, but almost no information is available about the effect of common maternal diseases during pregnancy. This paper reports the effects of maternal morbidity during pregnancy on birth weight in four rural villages of Guatemala. Maternal morbidity, assessed through fortnightly interviews during pregnancy, showed a consistent inverse association with birth weight (r = —0.149, n = 344, p<0.01). In each village, the proportion of low birth weight babies born to mothers who were ill more than 10 percent of their pregnancy was consistently higher than the proportion of babies born to mothers who were sick 10 percent (or less) of their pregnancy (p<0.01). The relationship between the proportion of time ill and birth weight was basically unchanged (r = —0.182, n = 334, p<0.01) after controlling for maternal height, head circumference, parity, gestational age, socioeconomic status, home energy intake, energy supplementation during pregnancy and number of days surveyed during pregnancy. Moreover, a similar association was found in consecutive pregnancies of the same mother (r = —0.197, n = 50, p = 0.16). It was concluded that maternal morbidity during pregnancy caused a decrease in birth weight. In addition, an inverse association was observed between the proportion of time ill during pregnancy and home energy intake (r = —0.254, n = 334, p<0.01). However, the amount of birth weight variance explained by morbidity during pregnancy did not decrease significantly after statistically controlling for home energy intake. Therefore, either the diet measurement is imprecise or the decrease in energy intake observed during illness was not an important mechanism. 相似文献
998.
Loss of EpCAM expression in breast cancer derived serum exosomes: role of proteolytic cleavage 总被引:1,自引:0,他引:1
Rupp AK Rupp C Keller S Brase JC Ehehalt R Fogel M Moldenhauer G Marmé F Sültmann H Altevogt P 《Gynecologic oncology》2011,122(2):437-446
Objective
Cancer cells in the body release soluble and membranous factors that manipulate the tumor environment to facilitate growth and survival. Recent years have provided evidence that small microvesicles that are termed exosomes may play a pivotal role in this process. Exosomes are membrane vesicles with a size of 40-100 nm that are released by both tumor and normal cells and can be found in various body fluids. Tumor-derived exosomes carry functional proteins, mRNAs, and miRNAs and could serve as novel platform for tumor diagnosis and prognosis. However, marker proteins that allow enrichment of tumor-derived exosomes over normal exosomes are less well defined.Methods
We used Western blot analysis and antibody coupled magnetic beads to characterize CD24 and EpCAM as markers for exosomes. We investigated ovarian carcinoma ascites, pleural effusions and serum of breast carcinoma patients. As non-tumor derived control we used exosomes from ascites of liver cirrhosis patients.Results
Exosomes could be isolated from all body fluids and contained marker proteins as well as miRNAs. We observed that CD24 and EpCAM were selectively present on ascites exosomes of tumor patients and copurified together on anti-EpCAM or anti-CD24 magnetic beads. In breast cancer patients CD24 was present but EpCAM was absent from serum exosomes. Instead, the intact EpCAM ectodomain was recovered in a soluble form. We provide evidence that EpCAM can be cleaved from exosomes via serum metalloproteinase(s).Conclusion
Loss of EpCAM on serum exosomes may hamper enrichment by immune-affinity isolation. We suggest that CD24 could be an additional marker for the enrichment of tumor-derived exosomes from blood. 相似文献999.
目的:观察不孕女性阴道微生态和阴道菌群状况,探讨不孕症女性进行阴道微生态和菌群评价的临床价值。方法:收集本院收治不孕症女性150例,同期100例育龄期体检健康妇女作为对照组;比较两组阴道分泌物的微生态状况和Nugent评分;采取细菌培养法检测两组阴道分泌物菌群分布。结果:对照组和不孕组在阴道分泌物的多样性、密集度、优势菌、p H值以及清洁度方面,比较差异均无统计学意义(P〉0.05)。对照组和不孕组的阴道分泌物Nugent评分在≥7分、4~6分和0~3分三个层次比较,差异均无统计学意义(P〉0.05)。对照组和不孕组在培养菌群金黄色葡萄球菌、大肠艾希氏菌、肠杆菌、酵母样菌和表皮葡萄球菌的检出率比较,差异均无统计学意义(P〉0.05)。两组清洁度异常者革兰阳性球菌、革兰阴性杆菌、革兰阴性球菌、革兰阴性双球菌、霉菌、滴虫、加德纳菌检出率比较差异均无统计学意义(P〉0.05)。结论:不孕症女性和育龄期健康女性的阴道微生态状况、BV患病率以及阴道菌群分布方面比较无显著性差异。 相似文献
1000.
微RNAs是由19-23个核苷酸组成的RNA分子。它们能够中止mRNAs的翻译或降解mRNA,从而成为蛋白质表达的调控者。微RNAs能有力推进细胞的分化和发育。这种调节的异常相关β细胞生物学、胰岛素抵抗和糖尿病及其并发症。微RNA-375直接参与胰岛素分泌的调控。本研究证明,微RNAS密切相关于疾病的表现。近年新鉴定出一大批与疾病致病有关的微RNAs。本文所提供31种微RNAs的应用,仅作为研究案例如糖尿病肾病发病的趣谈,旨在引起《中国糖尿病杂志》读者和作者研究微RNAs的浓厚兴趣。 相似文献