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91.
目的探讨血管内皮生长因子(VEGF)、微血管密度(MVD)及Ki-67在宫颈鳞状细胞癌中的表达及意义。方法采用免疫组织化学S-P法测定45例宫颈鳞癌组织和10例正常宫颈组织中VEGF、Ki-67和F8的表达。结果宫颈鳞癌中VEGF的表达阳性率为77.78%,Ki-67标记指数(Ki-67LI)和MVD分别为12.7±4.1和37±10,VEGF表达水平与肿瘤恶性程度、Ki-67 LI和MVD计数呈正相关。结论VEGF有促进肿瘤细胞增殖及血管生成的作用,联合检测VEGF、Ki-67和F8可作为病理诊断的补充,对患者预后判断和治疗方案的选择有重要的参考价值。  相似文献   
92.
In three-dimensional (3D) printing, one of the main parameters influencing the properties of 3D-printed materials is the infill density (ID). This paper presents the influence of ID on the microstructure, mechanical, and thermal properties of carbon fiber-reinforced composites, commercially available, manufactured by the Fused Filament Fabrication (FFF) process. The samples were manufactured using FFF by varying the infill density (25%, 50%, 75%, and 100%) and were subjected to tensile tests, three-point bending, and thermal analyses by Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). It was shown that the samples with 100% ID had the highest values of both tensile, 90.8 MPa, and flexural strengths, 114 MPa, while those with 25% ID had the lowest values of 56.4 MPa and 62.2 MPa, respectively. For samples with infill densities of 25% and 50%, the differences between the maximum tensile and flexural strengths were small; therefore, if the operating conditions of the components allow, a 25% infill density could be used instead of 50%. After DSC analysis, it was found that the variation in the ID percentage determined the change in the glass transition temperature from 49.6 °C, for the samples with 25% ID, to 32.9 °C, for those with 100% ID. TGA results showed that the samples with IDs of 75% and 100% recorded lower temperatures of onset degradation (approximately 344.75 °C) than those with infill densities of 25% and 50% (348.5 °C, and 349.6 °C, respectively).  相似文献   
93.
唐才环  薛芳  陈乙云  陈霞  黄惠敏 《安徽医药》2024,28(7):1425-1429
目的探讨干扰素调节因子 5(interferon regulatory factor 5,IRF5)、粒细胞 -巨噬细胞集落刺激因子( granulocyte-macrophage colony-stimulating factor,GM-CSF)在细菌性肺炎病儿血清中的表达变化及疾病预后价值。方法选取 2019年 4月至 2021年 5月中国人民解放军联勤保障部队第九二八医院收治的细菌感染性肺炎病儿 96例作为细菌组,同期非细菌感染性肺炎病儿 88例作为非细菌组,另外选取健康体检儿童 96例为对照组,收集检测三组病儿基本临床资料。检测血清中 IRF5、GM-CSF及其组间差异;采用 Pearson法分析细菌性肺炎病儿血清 IRF5、GM-CSF水平与病情指标的相关性;应用受试者操作特征曲线(ROC曲线)分析 IRF5、GM-CSF及二者联合预测细菌性肺炎预后的价值。结果细菌组血清 IRF5水平[(38.85±13.86)ng/L]显著高于非细菌组[( 11.15±4.37)ng/L]和对照组[( 10.76±1.55)ng/L],且重症组高于轻症组( P<0.05);细菌组血清 GM-CSF水平[(54.73±16.56)ng/L]显著低于非细菌组[(246.73±28.94)ng/L]和对照组[(250.64±55.67)ng/L],且重症组低于轻症组( P<0.05)。重症组气促、吐沫、三凹征、肺部明显湿啰音比例、 C反应蛋白( C-reactive protein,CRP)、白细胞水平显著高于轻症组、非细菌组(P<0.05)轻症组、非细菌组 CRP水平显著高于对照组( P<0.05),非细菌组 CRP水平显著高于对照组( P<0.05)。血清 IRF5水平与 CRP、,白细胞、临床肺部感染评分( clinical pulmonary infection score,CPIS)均呈正相关( r=0.34、0.36、0.41,P<0.05)血清 GM-CSF水平与 CRP、白细胞、 CPIS均呈负相关( r=-0.40、-0.32、-0.45,P<0.05)。预后不良组血清 IRF5水平高于预后良好,组,血清 GM-CSF水平低于预后良好组( P<0.05)。 ROC曲线显示, IRF5、GM-CSF对预后预测的 AUC分别为 0.90、0.87,二者联合对预后预测的 AUC为 0.96,明显高于二者单独诊断,(Z联合 vs.IRF5=2.86,P=0.004;Z联合 vs.GM-CSF =2.24,P=0.025),其灵敏度、特异度分别为 90.32%、90.77%。结论细菌性肺炎病儿血清 IRF5水平升高, GM-CSF水平降低,二者在评估病情进展及疾病预后预测方面具有较高的价值。  相似文献   
94.
目的 探索第三代双源CT在心律不齐患者冠状动脉CT血管造影(CT angiography,CTA)扫描过程中的应用.方法 选择本院收治的心律不齐患者96例,随机分为对照组和观察组进行CTA扫描,各48例.对照组给予第一代双源CT上行常规CT技术进行检查,观察组给予第三代双源CT上行低管电压、低剂量碘造影剂的双低技术进行...  相似文献   
95.
The purpose of breast cancer screening is to find cancers early to reduce mortality and to allow successful treatment with less aggressive therapy. Mammography is the gold standard for breast cancer screening. Its efficacy in reducing mortality from breast cancer was proven in randomized controlled trials (RCTs) conducted from the early 1960s to the mid 1990s. Panels that recommend breast cancer screening guidelines have traditionally relied on the old RCTs, which did not include considerations of breast density, race/ethnicity, current hormone therapy, and other risk factors. Women do not all benefit equally from mammography. Mortality reduction is significantly lower in women with dense breasts because normal dense tissue can mask cancers on mammograms. Moreover, women with dense breasts are known to be at increased risk. To provide equity, breast cancer screening guidelines should be created with the goal of maximizing mortality reduction and allowing less aggressive therapy, which may include decreasing the interval between screening mammograms and recommending consideration of supplemental screening for women with dense breasts. This review will address the issue of dense breasts and the impact on the stage of breast cancer at the time of diagnosis, and discuss options for supplemental screening.  相似文献   
96.
目的 评价Atlas9000、Orbscan及Pentacam三种方法测量近视患者角膜非球面系数(Q值)的差异和一致性。方法 横断面比较性研究,随机选取在广西视光中心就诊的成年近视患者49例(98眼),分别应用Atlas9000、Orbscan及Pentacam测量患者的角膜Q值。采用随机区组设计资料的方差分析(Two-wayANOVA)比较不同仪器测量结果的差异,采用Pearson相关系数分析不同仪器测量结果的相关性,采用Bland-Altman分析评价不同方法测量结果的一致性。结果 Atlas9000、Orbscan及Pentacam测得的角膜Q值分别为-0.342±0.135、-0.302±0.182和-0.305±0.120,三种方法测得角膜Q值差异有统计学意义(F=5.465,P=0.005),两两比较表明Atlas9000与Orbscan、Pentacam的检测结果比较差异均有统计学意义(均为P<0.05),测得负值更大,但Orbscan与Pentacam检测结果间比较差异无统计学意义(P>0.05)。Pearson相关分析显示,Atlas9000、Orbscan与Pentacam测得的角膜Q值之间均有正相关性(均为P<0.001)。Bland-Altman一致性分析表明Atlas9000与Pentacam一致性好。结论 Atlas9000、Orbscan及Pentacam测量近视患者角膜Q值存在一定差异,但Atlas9000与Pentacam的一致性较好,两者可相互参考。  相似文献   
97.
Clinical research continues to provide an increasing number of studies that reveal an association between macular pigment optical density (MPOD) and both visual function and ocular health. As a result, there is a growing need for repeatable, accurate measures of MPOD that can describe peak optical density as well as spatial distribution. Measurement of MPOD in a research setting has an established history encompassing a number of both objective and subjective techniques. Transition of these techniques to a clinical setting has produced an array of commercial devices using three primary methods: heterochromatic flicker photometry, fundus autofluorescence and fundus reflectometry. The inherent differences among the techniques create difficulty in making direct comparisons between MPOD measurement devices. Understanding the limitations of each technique is critical in the clinical interpretation of MPOD results. Here, both the objective and subjective methods of MPOD measurement are reviewed with emphasis on the commercially available devices used in clinical settings.  相似文献   
98.
Purpose: The aim of our study was to investigate the biomechanical properties of the cornea in primary congenital glaucoma (PCG) and to identify the potential ocular determinants, which affect the corneal biomechanical metrics. Methods: Corneal hysteresis (CH), corneal resistance factor (CRF) and central corneal thickness (CCT) were measured in 26 patients with PCG (40 eyes) with the aid of ocular response analyser. In vivo laser‐scanning confocal microscopy was used for the estimation of stromal keratocyte density (KD) and the evaluation of corneal endothelium. Twenty normal subjects (40 eyes) served as controls. Student’s t‐test and Pearson’s correlation coefficients were used for statistical analysis. p Values <0.05 were considered statistically significant. Results: Corneal hysteresis, CRF and CCT were significantly reduced in patients with PCG (all p < 0.05). Corneal hysteresis and CRF negatively correlated with the corneal diameter in both groups (r1 = ?0.53, r2 = ?0.66, p < 0.001 for CH and r1 = ?0.61, r2 = ?0.69, p < 0.001 for CRF). Moreover, we identified a significant correlation between CH and CRF with CCT in both groups (r1 = 0.51, r2 = 0.48, p < 0.001 for CH and r1 = 0.45, r2 = 0.44, p < 0.001 for CRF). Mean KD was significantly reduced both in the anterior and posterior corneal stroma in patients with PCG (764 ± 162 and 362 ± 112 cells/mm2, respectively) compared with controls (979 ± 208 and 581 ± 131 cells/mm2, respectively) (p < 0.001). There was no significant correlation between the keratocyte density in anterior and/or posterior stroma and CH or CRF in any group (r1 = 0.29, r2 = 0.31, p < 0.06). Mean endothelial cell density was also significantly reduced in PCG group (2920 ± 443 cells/mm2) compared with control group (3421 ± 360 cells/mm2) (p < 0.001). Pleomorphism and polymegalism were significantly increased in corneal endothelium of patients with PCG. Conclusions: Our results showed a significant reduction in CH and CRF in PCG. Both CH and CRF were negatively correlated with corneal diameter. A significant correlation of CH and CRF with CCT was identified in both groups. Keratocyte density was decreased in PCG, but did not have a significant impact on CH and CRF. Mean endothelial density was also decreased in PCG. Our results suggest that reduced CCT and increased corneal diameter are major ocular determinants for the modified corneal biomechanical profile in PCG, while cellular alterations in corneal stroma and endothelium have no significant biomechanical impact.  相似文献   
99.
四种补肾中药对去卵巢大鼠骨质疏松骨形态的作用   总被引:35,自引:0,他引:35  
目的 比较骨碎补、锁阳、淫羊藿和狗脊4种补肾中药对去卵巢(OVX)大鼠骨质疏松的作用。方法 将54只3月龄雌性Wistar大鼠随机分成模型组和中药治疗组。模型组包括非手术组、假手术组和去卵巢组,每组10只;中药组包括骨碎补组、锁阳组、淫羊藿组和狗脊组,每组6只。去卵巢手术后1周,中药组分别用上述4种中药喂养,8周后放血外死全部小鼠,用骨形态主坦学方法比较4种中药对OVX大鼠骨质疏松的防治作用。结果  相似文献   
100.
In the course of 280 consecutive gamete intrafallopian transfer (GIFT) attempts, supernumerary oocytes in excess of those transferred were inseminated in vitro. Pregnancy resulted in 31.1% of patients following the GIFT treatment. The overall in vitro fertilization (IVF) rate of supernumerary oocytes was significantly higher in those who became pregnant (41.2%) than in patients who did not (34.9%). However, the failure to fertilize any supernumerary oocytes was not significantly different between those becoming pregnant (27.6%) and those in whom the treatment failed (37.3%). Failure to fertilize any supernumerary oocytes in vitro was of a higher rate if suboptimal sperm preparation was used or if only one oocyte was left over for in vitro insemination following the GIFT treatment. We concluded that the in vitro fertilization rate was higher in the pregnant group, but the total failure to fertilize or the fertilization of any supernumerary oocytes does not predict the outcome of GIFT. Embryos resulting following fertilization of excess oocytes may be cryopreserved for subsequent use.  相似文献   
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