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991.
J Oral Pathol Med (2013) 42 : 148–153 Background: Oral erythroplakia (OE) is a notoriously aggressive oral pre‐malignant lesion with a high tendency to oral cancer development, but its biological behavior is largely unknown. The objective of this study was to determine the expression of cancer stem cell markers ALDH1 and Bmi1 in OE and their correlation with malignant transformation of OE. Methods: In a retrospective case–control study, expression patterns of ALDH1 and Bmi1 were determined using immunohistochemistry in samples from 34 patients with OE, including patients with untransformed lesions (n = 17) and patients with malignant transformed lesions (n = 17). Results: ALDH1 and Bmi1 expression was observed in 19 (55.9%) and 20 (58.8%) of 34 patients with OE, respectively. Multivariate analysis revealed that ALDH1 expression was significantly associated with increased risk of transformation (P < 0.05), but Bmi1 expression was not a significant marker (P > 0.05). Notably, the coexpression of both ALDH1 and Bmi1 was a strong indicator associated with 8.56‐fold (95% confidence interval [CI], 1.74–42.17; P < 0.01) for malignant transformation. Point prevalence analysis revealed that 78.6% (95% CI, 54.0–100) of the patient with coexpression of both ALDH1 and Bmi1 developed oral cancer. Conclusion: Our data indicated that the expression patterns of ALDH1 and Bmi1 in OE were associated with malignant transformation, suggesting that they may be valuable predictors for evaluating the risk of oral cancer.  相似文献   
992.
目的:探究翁连解毒汤治疗浊毒内蕴型溃疡性结肠炎(Ulcerative Colitis,UC)临床疗效及可能的作用机制。方法:选取2016年2月至2018年12月在攀枝花学院附属医院收治的浊毒内蕴型UC患者130例作为研究对象,按照入院先后顺序分为对照组和观察组,每组65例。对照组常规西医治疗,观察组加用翁连解毒汤,观察2组治疗前、完成治疗后T细胞、NK细胞、炎性反应因子、凝血功能、生命质量变化,完成治疗后总结疗效。结果:观察组患者在NK细胞、T淋巴细胞组成、CR、TNF-α、IL-1 β、ESR、内毒素、IL-10、FIB、PLT、APTT改善方面的效果较对照组更优,组间差异有统计学意义(P<0.05)。观察组患者完成治疗后的生命质量量表各维度评分及总评分改善效果优于对照组患者(P<0.05),且临床总有效率和组织病理学疗效率均高于对照组患者(P<0.05)。结论:翁连解毒汤能抑制浊毒内蕴型UC炎性反应,改善高凝状态,提高机体免疫功能,从而提高疗效和生命质量。  相似文献   
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995.
The purpose of this study was to compare cyclic fatigue (CF) resistance of reciprocating instruments at body temperature and relate the findings to their martensitic transformation temperatures. Contemporary nickel‐titanium (NiTi) reciprocating instruments WaveOne Primary, WaveOne Gold Primary and EdgeFile X1 (n = 20 each and #25 tip diameter) were tested for CF resistance at body temperature (37 ± 1°C). Instruments were actioned according to manufacturer guidelines until fracture occurred in a simulated canal (angle of curvature = 60°, radius of curvature = 3 mm and centre of curvature = 5 mm from the tip). Time to fracture was recorded, and data analysed using Weibull analysis. Two instruments of each were tested using differential scanning calorimetry (DSC) to assess phase transformation temperatures. Reciprocating instruments manufactured with new alloys seem to be safer to CF than those manufactured with traditional M‐Wire at body temperature. Martensitic transformation temperatures seem not to relate with fatigue behaviour for reciprocating motions.  相似文献   
996.
目的测定冻干血小板长期保存预冻程序和所依据的制品相变点温度并摸索相应屏蔽相变点的最佳冷冻曲线。方法研制出小分子糖负载血小板+冻干保护剂混合悬液,使用速率程序降温仪分析测定该混合悬液样品的相变点温度;根据测得的相变点温度,设计屏蔽相变点的预冻程序,根据温度变化曲线,判断相变点屏蔽结果。结论该混合悬液样品的相变点温度为(-13.56±2.05)℃;据此相变点温度所设计的3种相应的屏蔽相变点的预冻程序中,程序3为最佳冷冻曲线。结果获得了小分子糖负载血小板+冻干保护剂混合悬液的相变点温度及相应的屏蔽相变点的最佳预冻程序。  相似文献   
997.
Patients with diabetes mellitus (DM) often have alterations of the autonomic nervous system (ANS), even early in their disease course. Previous research has not evaluated whether these changes may have consequences on adaptation mechanisms in DM, e.g. to mental stress. We therefore evaluated whether patients with DM who already had early alterations of the ANS reacted with an abnormal regulatory pattern to mental stress. We used the spectral analysis technique, known to be valuable and reliable in the investigation of disturbances of the ANS. We investigated 34 patients with DM without clinical evidence of ANS dysfunction (e.g. orthostatic hypotension) and 44 normal control subjects (NC group). No patients on medication known to alter ANS responses were accepted. The investigation consisted of a resting state evaluation and a mental stress task (BonnDet). In basal values, only the 21 patients with type 2 DM were different in respect to body mass index and systolic blood pressure. In the study parameters we found significantly lower values in resting and mental stress spectral power of mid-frequency band (known to represent predominantly sympathetic influences) and of high-frequency and respiration bands (known to represent parasympathetic influences) in patients with DM (types 1 and 2) compared with NC group (5·3 ± 1·2 ms2 vs. 6·1 ± 1·3 ms2, and 5·5 ± 1·6 ms2 vs. 6·2 ± 1·5 ms2, and 4·6 ± 1·7 ms2 vs. 6·2 ± 1·5 ms2, for resting values respectively; 4·7 ± 1·4 ms2 vs. 5·9 ± 1·2 ms2, and 4·6 ± 1·9 ms2 vs. 5·6 ± 1·7 ms2, and 3·7 ± 2·1 ms2 vs. 5·6 ± 1·7 ms2, for stress values respectively; M/F ratio 6/26 vs. 30/14). These differences remained significant even when controlled for age, sex, and body weight. However, patients with DM type 2 (and significantly higher body weight) showed only significant values in mental stress modulus values. There were no specific group effects in the patients with DM in adaptation mechanisms to mental stress compared with the NC group. These findings demonstrate that power spectral examinations at rest are sufficiently reliable to diagnose early alterations in ANS in patients with DM. The spectral analysis technique is sensitive and reliable in investigation of ANS in patients with DM without clinically symptomatic autonomic dysfunction.  相似文献   
998.
This study evaluated acquired-immune functions representing the three major branches of the immune system in male rats fed a commercially available echinacea product. An additional comparison of effects on antibody formation in male and female rats was done using the commercial echinacea product and two echinacea tinctures marketed by local herbalists. In initial testing, we found no evidence of altered natural killer cell activity, T cell-mediated delayed-type hypersensitivity, or specific antibody formation in male rats given either a 225 mg/kg or 50 mg/kg of the commercial echinacea for 6 weeks. Antibody formation was significantly suppressed in female but not male rats given 250 mg/kg for 2 weeks of the commercial echinacea. The local products tested had no effect on antibody formation. We concluded that our study provided no supporting evidence for immunostimulatory activity by the echinacea preparations we examined and, in fact, may be immunosuppressive under some conditions.  相似文献   
999.
目的系统评价激光联合玻璃体腔注射雷珠单抗与单独玻璃体腔注射雷珠单抗治疗视网膜分支静脉阻塞(BRVO)继发黄斑水肿的疗效及安全性。方法通过检索PubMed、CNKI、万方等数据库收集有关治疗BRVO继发黄斑水肿的随机对照试验研究(RCT)。检索时间为建库至2019年5月。采用RevMan 5.3软件对纳入文献进行meta分析。结果共纳入12篇文献,包括1081例患者。meta分析结果显示:与单纯注药组相比,联合治疗组黄斑中心凹厚度(CMT)在随访1、3、6个月时均降低,差异有统计学意义[95%CI(-135.44^-15.54),P<0.001];但对于最佳矫正视力(BCVA)的提高,2组间无统计学差异[95%CI(-1.75~0.80),P>0.05];2组不良反应的发生率无统计学差异[OR=1.50,95%CI(0.97~2.30),P=0.07]。结论激光联合玻璃体腔注射雷珠单抗能够显著降低BRVO继发黄斑水肿患者的CMT,早期疗效优于单纯注药组。但两种方式对于治疗后BCVA的影响及不良反应的发生尚需要大样本的随机对照双盲研究加以验证。  相似文献   
1000.
目的 探讨脑膜瘤术后复发并恶变的靶向治疗效果。方法 回顾性分析1例鞍区脑膜瘤的临床资料,并结合相关文献进行分析。结果 52岁男性,因鞍区脑膜瘤切除术后13年伴视力进行性下降3年于2020年5月12日入院;2007年首次手术近全切除鞍区肿瘤,术后病理示脑膜瘤(WHO分级Ⅰ级);2009年复查MRI显示肿瘤明显增大,2009~2018年共行6次伽玛刀治疗;2019年复查MRI显示肿瘤无增大;2020年复查MRI显示肿瘤再次明显增大,再次手术全切除肿瘤,术后病理示不典型脑膜瘤(WHO分级Ⅱ级),6个月后肿瘤再次复发,根据基因检测和类器官培养的药敏结果,选择舒尼替尼进行靶向治疗(37.5 mg,1次/d,持续4周,停药2周);靶向治疗6个月复查MRI显示肿瘤缩小,但9个月时复查MRI显示肿瘤增大,病人拒绝继续靶向治疗,神志清楚,双目失明,能搀扶行走。结论 脑膜瘤术后复发并恶变时,靶向治疗短期内可缩小肿瘤体积,长期效果有待继续研究。  相似文献   
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