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1.
目的初探牙周状况、龈下螺旋体和早产低体重儿(PLWB)发生之间的关系。方法从住院病例库中按严格标准选出PLWB组(49例)和Control组(20例),电话召回填写调查问卷、单盲检查口腔牙周情况(PLI、BI、PD)并计数指数牙(16、21、24、36、41、44)的CAL和龈下螺旋体比例,用统计学软件处理最终数据。结果PLWB组83.7?L>0,Control组55.0%,P<0.05;两组所有指数牙的PD、CAL和龈下螺旋体比例均为PLWB组大于Control组,P<0.05都是下颌牙位。结论PLWB组牙周破坏倾向于比Control组更重;龈下螺旋体或许可以充当一个粗略的PLWB预示指标。  相似文献   
2.
Rely X ARC粘接系统粘接Ⅱ类洞嵌体一年的临床评价   总被引:3,自引:0,他引:3  
目的通过临床研究评价Rely X ARC粘接系统对Ⅱ类洞嵌体的粘接效果。方法30个后牙Ⅱ类洞使用同种金合金嵌体及Rely X ARC粘接系统修复后,通过改良的USPHS标准评估嵌体粘接后2周、6个月、1年的临床指标。结果所有嵌体6个月和1年的各项指标得分均在临床可接受的范围内。结论Rely X粘接系统对于金合金嵌体修复后牙Ⅱ类洞有比较可靠的短期效果,长期效果有待继续验证。  相似文献   
3.
4.
Wu L  Li Z  Zhang Y  Zhang P  Zhu X  Huang J  Ma T  Lu T  Song Q  Li Q  Guo Y  Tang J  Ma D  Chen KH  Qiu X 《Molecular cancer therapeutics》2008,7(1):222-232
Hyperplasia suppressor gene (HSG), also called human mitofusin 2, is a novel gene that markedly suppresses the cell proliferation of hyperproliferative vascular smooth muscle cells from spontaneously hypertensive rat arteries. This gene encodes a mitochondrial membrane protein that participates in mitochondrial fusion and contributes to the maintenance and operation of the mitochondrial network. In this report, we showed that an adenovirus vector encoding human HSG (Ad5-hHSG) had an antitumor activity in a wide range of cancer cell lines. We further focused on the lung cancer cell line A549 and the colon cancer cell line HT-29 and then observed that Ad5-hHSG induced apoptosis both in vitro and in vivo. Confocal laser scanning microscopy and electron microscopy revealed that cells infected with Ad5-hHSG formed dose-dependent perinuclear clusters of fused mitochondria. Adenovirus-mediated hHSG overexpression induced apoptosis, cell cycle arrest, mitochondrial membrane potential (DeltaPsim) reduction and release of cytochrome c, caspase-3 activation, and cleavage of PARP in vitro. Overexpression of hHSG also significantly suppressed the growth of subcutaneous tumors in nude mice both ex vivo and in vivo. In addition, Ad5-hHSG increased the sensitivity of these cell lines to two chemotherapeutic agents, VP16 and CHX, and radiation. These results suggest that Ad5-hHSG may serve as an effective therapeutic drug against tumors.  相似文献   
5.
6.
Osteogenesis imperfecta (OI) is a congenital disorder caused most often by dominant mutations in the COL1A1 or COL1A2 genes that encode the alpha chains of type I collagen. Severe forms of OI are associated with skeletal deformities and frequent fractures. Skeletal pain can occur acutely after fracture, but also arises chronically without preceding fractures. In this study we assessed OI-associated pain in the Col1a1Jrt/+ mouse, a recently developed model of severe dominant OI. Similar to severe OI in humans, this mouse has significant skeletal abnormalities and develops spontaneous fractures, joint dislocations and vertebral deformities. In this model, we investigated behavioral measures of pain and functional impairment. Significant hypersensitivity to mechanical, heat and cold stimuli, assessed by von Frey filaments, radiant heat paw withdrawal and the acetone tests, respectively, were observed in OI compared to control wildtype littermates. OI mice also displayed reduced motor activity in the running wheel and open field assays. Immunocytochemical analysis revealed no changes between OI and WT mice in innervation of the glabrous skin of the hindpaw or in expression of the pain-related neuropeptide calcitonin gene-related protein in sensory neurons. In contrast, increased sensitivity to mechanical and cold stimulation strongly correlated with the extent of skeletal deformities in OI mice. Thus, we demonstrated that the Col1a1Jrt/+ mouse model of severe OI has hypersensitivity to mechanical and thermal stimuli, consistent with a state of chronic pain.  相似文献   
7.
Background

Acute myeloid leukemia (AML) is a heterogeneous blood disease with poor treatment effect and high recurrence rate. With the deepening of non-coding RNA research, more and more miRNAs have been found to participate in various physiological processes of tumors. In this study, we tried to find the miRNA related to the prognosis of AML.

Methods

Collect gene expression data and clinical information of AML patients in the Cancer Genome Atlas database for statistical analysis. The expression level of miR-195 of each patient was standardized by logCPM and then produced as a box plot according to subtype classification. TargetScan was used to predict the target genes of miR-195, and these genes were subjected to GO pathway enrichment analysis by Metascape. Differential miRNAs were screened through the DESeq2 package in the R language. Survival rates were estimated using the Kaplan–Meier method and the log-rank test. The multivariate Cox proportional hazard models of EFS and OS were established.

Results

We found that the expression of miR-195 was the lowest in cytogenetically normal (CN-) AML, and high expression of miR-195 only promoted the prognosis of chemotherapy-only CN-AML patients (EFS: P?=?0.016; OS: P?=?0.035). Multivariate analysis showed that miR-195high was a favorable and independent factor for CN-AML (both P?<?0.05). Further analysis showed that miR-195 may affect signal transduction through ANHAK2 in AML.

Conclusion

We found that high expression of miR-195 can increase prognosis time of chemotherapy-only CN-AML patients, providing a new possibility for treatment.

  相似文献   
8.
目的通过超声生物显微镜(UBM)观察原发性虹膜睫状体囊肿的形态学特征,分析囊肿与邻近房角的关系,以及多发性囊肿对全周房角的影响范围和程度。方法除外原发性房角狭窄或关闭,有眼科手术及眼外伤史的个体,从我院眼科门诊随机选取50例13~40岁患者为青少年组,60例41~70岁患者为中老年组。用UBM对患者每只眼全周进行扫查,分析青少年组与中老年组间原发性虹膜睫状体囊肿形态学差异。比较囊肿形态与邻近房角狭窄或关闭的关系。当多发性囊肿导致房角≥2个窄角及闭角时,估测囊肿导致全部窄角和闭角的范围占此眼周长的比例。结果本组UBM检查对原发性虹膜睫状体囊肿检出率为31.8%,其中多发者占62.9%。对于局部房角,体积越大的囊肿引起房角狭窄或关闭的可能性越大(P<0.05);位于睫状冠前表面、虹膜根部后表面及临近睫状沟的囊肿对房角的影响亦较大(P=0.05)。青少年组与中老年组囊肿发生率分别为40.0%和25.0%(P<0.05);平均最大径分别为(0.51±0.54)mm和(0.31±0.17)mm(P<0.05);多发性囊肿在组内比例分别为75.0%和46.6%(P<0.05);多发性囊肿引起单眼多发性房角狭窄及关闭的病例均发生于青少年组,占该组发生囊肿眼的12.5%。结论青少年组较中老年组发生囊肿的数量多、体积大、易多发,更易导致多点房角狭窄及关闭。原发性虹膜睫状体囊肿可能是引起青少年继发性房角狭窄和关闭的主要原因之一。  相似文献   
9.
目的:采用淋巴细胞转化率为指标研究漂浮疗法对个体免疫功能的影响。方法:以淋巴细胞转化率作为免疫功能变化指标。被试为43名大学生(男22名,女21名),年龄18~24岁。被试随机分为4组,其中前3组均采用漂浮疗法,但具体过程略有不同。第1组:漂浮,播放漂浮治疗专用音乐;第2组:漂浮,通过内部通讯系统进行放松指导;第3组:漂浮,无任何听觉刺激;第4组为对照组。每人完成4次治疗。结果:各组被试治疗前的淋巴细胞转化率没有显著性差异(F=0.733P=0.539)。采用漂浮治疗的各组中,只有第3组淋巴细胞转化率在治疗前后有显著性差异犤(91.7±4.2)%vs(84.8±7.2)%犦,而对照组治疗前后该项检查的结果也有显著性差异犤(93.0±2.8)%vs(89.3±4.2)%犦。第3组被试治疗前后淋巴细胞转化率变化显著大于第2组被试(t=2.168,P=0.043)。男女被试的淋巴细胞转化率在治疗前分别为87.68%和86.95%,两者没有显著性差异(t=0.314,P=0.755)。男女被试的淋巴细胞转化率在治疗前后的变化没有显著性差异(t=0.503P=0.620)。结论:漂浮疗法的确可以提高被试的细胞免疫功能,但是漂浮治疗中使用额外的听觉刺激可能会影响到改善免疫力的作用。性别对于淋巴细胞转化率变化没有显著影响。该研究的结果在应用于临床前,尚需要进一步研究。  相似文献   
10.
Two compatible conversion factors for converting diameter measurements taken at different breast heights were derived for Pinus radiata using taper data from more than 3000 trees. The two breast heights used for conversion were 1.3 and 1.4 m above ground, as defined in Australia and New Zealand, two major radiata-growing countries in the world. The conversion factors were estimated through three alternative statistical methods including simple least squares regression, seemingly unrelated regression and errors-in-variables models. The three sets of estimates were almost identical and had similar conversion accuracy, although the second method was slightly better. The conversion factors were more accurate than overbark taper equations used for the same purpose. The factor was 0.9916 for converting diameter measured at 1.3 to that at 1.4 m above ground, and the inverse of this value, 1.0084, was for the vice versa. When calculating tree and stand volume and biomass using equations with diameter at a different breast height as a predictor to that of the input data, the bias, either over or under estimation, could be between 1.67% and 2.00% without conversion. These conversion factors will facilitate the sharing of data among radiata growing countries with different definitions of breast height, but more importantly it will help correct the bias in stand volume and biomass estimation caused by the seemingly negligible difference in breast height when software for forest resource management and decision support developed in one country is applied in another. Such bias when accumulated over a large management area may not be financially insignificant for an astute forest management agency.  相似文献   
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