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91.
92.
Recent studies show that thiazolinediones (TZDs), agonists of the peroxisome proliferator-activated receptor gamma (PPARgamma), induce apoptosis in glioma and glioblastoma cells. Here we compared the effects of troglitazone (Trog), a TZD with low affinity for binding to PPARgamma but with potent metabolic effects, on survival and metabolism in GL261 glioma cells versus primary astrocytes. Trog dose-dependently induced cell death in GL261 cells (with over 90% death at 30 microM) but did not cause any toxicity in astrocytes at the same doses. Measurements of glucose and lactate levels after incubation with Trog (30 microM) indicated an overall increase of glucose consumption and lactate production in both cell types. In astrocytes the ratio of lactate produced to glucose utilized was not significantly altered by Trog, while in glioma cells this ratio was decreased by about 40%. Trog dose-dependently reduced mitochondrial membrane potential (DeltaPsi(m)) in both cell types; and the loss of DeltaPsi(m) was greater in the tumor cells (90% loss at 20 microM) than in astrocytes (70% loss at 20 microM). These results suggest that differences in metabolic responses could contribute to the selective resistance of astrocytes to cytotoxic effects of Trog. TZDs such as Trog should therefore be considered for testing in treatment of gliomas.  相似文献   
93.
BACKGROUND: The authors assessed the utilization of oral health care professionals (OHCPs) as a resource for identifying patients who were unaware of their increased risk of developing cardiovascular disease (CVD). METHODS: OHCPs administered a CVD risk-screening questionnaire, measured blood pressure and tested cholesterol levels, high-density lipoprotein levels and hemoglobin A1c (HgA1c) levels using "finger-stick" blood testing in 100 patients treated in a dental school clinic who were unaware of their CVD risk status. The authors determined the prevalence of specific risk factors (that is, smoking and abnormal levels of systolic blood pressure, lipids, body mass index and HgA1c) and calculated Framingham 10-year coronary heart disease (CHD) risk scores. RESULTS: Seventeen percent of the 100 patients (35 percent of men, 5 percent of women) had an increased global risk of experiencing a CHD event within 10 years (Framingham risk score>10 percent). Seventy-three percent of participants had one or more risk factors and 31 percent had two or more risk factors present. More men than women had low levels of high-density lipoprotein (45 percent [18/40] of men versus 3.3 percent [2/60] of women; P<.0001). The mean Framingham CHD risk score increased with increasing risk factor burden. CONCLUSIONS: OHCPs identified patients with an increased CHD risk who could benefit from primary prevention activities. A substantial proportion of study patients who were unaware of their risk status were at an increased risk of experiencing a CHD event within 10 years. OHCPs could contribute to public health CHD control efforts.  相似文献   
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95.
背景 透射电子显微镜(TEM)是检测病毒的重要手段,传统TEM检测常依靠专家手工观察,操作步骤繁琐,且已有机器学习方法易受到背景、噪声的影响,导致病毒检测方法准确率差、效率低且耗时长。 目的 探讨增强图卷积神经网络(EGCN)对TEM图像中的病毒形态自动识别问题,以提高TEM病毒检测的效率。 方法 EGCN模型利用卷积神经网络(CNN)提取像素间的局部特征信息,并结合样本特征之间的最近邻关系利用图卷积网络(GCN)进行图特征学习。在模型优化中联合优化群体超分类损失和分类交叉熵损失以提高EGCN模型对病毒类别信息特征的提取能力,较CNN对TEM病毒图像特征具备更强的特征提取能力。 结果 通过不同方法在15类TEM病毒图像数据集上开展实验,EGCN达到3.40%的top-1错误率、1.88%的top-2错误率、96.65%的精确度和96.60%的召回率,并通过一系列对比实验表明EGCN模型可以有效避免TEM图像中背景、噪声等的影响,提高对病毒识别的准确率。 结论 EGCN可以有效解决病毒形态识别任务,为病毒的诊断提供重要的参考价值。  相似文献   
96.
目的:评价我院骨科髋关节置换术预防性应用抗菌药物整治活动的效果,以期逐步扩大抗菌药物专项整治成效,建立长效管理机制。方法:随机抽取我院骨科行髋关节置换术患者182例,其中2010年4月-2011年4月(整治活动前组)90例,2011年11月-2012年11月(整治活动后组)92例。对患者的自然情况、抗菌药物使用品种、使用时机、使用疗程等进行汇总及评价,并将结果应用SPSS 18.0软件进行统计分析,比较两组患者预防性应用抗菌药物的合理性。结果:开展抗菌药物专项整治后,抗菌药物预防性应用主要药物由第3代头孢菌素(31.11%)变为第1代头孢菌素(54.35%),其他各类药物的使用率均有显著下降(P<0.01);预防用药时机由大于术前2 h(58.89%)变为切皮前0.52 h(88.04%);用药疗程由平均(11.91±3.87)d变为(4.07±2.32)d;抗菌药物平均总费用下降71.06%。经过整治活动后药物选择不合理、术前用药不合理、更换药物不合理以及联合用药不合理的情况均有显著下降(P<0.01)。结论:抗菌药物专项整治活动后,我院骨科髋关节置换术预防性应用抗菌药物合理性得到明显改善,抗菌药物合理应用的长效管理机制已逐步建立。  相似文献   
97.
Cai  SP; Chang  CA; Zhang  JZ; Saiki  RK; Erlich  HA; Kan  YW 《Blood》1989,73(2):372-374
We used in vitro DNA amplification by the polymerase chain reaction and nonradioactive probes for prenatal diagnosis of beta thalassemia in Chinese from the Guangdong province. Exact molecular diagnoses were made in all 20 fetuses studied over a 6-month period. We conclude that this method of prenatal diagnosis for beta thalassemia is a viable approach in many parts of the world where this disease is common.  相似文献   
98.

Objectives

Diabetes mellitus (DM) and heart disease, among the most prevalent chronic conditions worldwide, are increasing among younger adults who are unaware of their risk status. Previous studies in the United States have shown the efficacy of screening for risk of heart disease and diabetes in a dental setting. A screening strategy was applied to facilitate early identification of individuals at increased disease risk in a single Indian dental institute.

Methods

158 patients >30 years old, with no reported heart disease or diabetes, and unaware of any increased disease risk were enrolled. Blood pressure, total cholesterol, high-density lipoprotein levels and body mass index were collected. The Framingham Risk Score (FRS) was calculated as an indication of global risk of developing a coronary heart disease (CHD) event within 10 years; hemoglobin A1c level was used to determine DM risk.

Results

Eleven percent had increased risk of heart disease (FRS >10 %) and 32 % had abnormal A1c levels (>5.7 %). At least one risk factor was present in 61 and 39 % presented with two or more risk factors. Hypertension and obesity were the most common risk factors.

Conclusions

The use of a dental setting in a developing country could serve as a resource for early identification of patients at increased risk of developing CHD and DM, yet unaware of their increased risk. The dental setting can also serve as an entry point into the medical care system by identifying asymptomatic patients at increased risk of disease and referring these individuals to a primary care provider.  相似文献   
99.

Purpose

The Children's Oncology Group (COG) renal tumor study (AREN03B2) requires real-time central review of radiology, pathology, and the surgical procedure to determine appropriate risk-based therapy. The purpose of this study was to determine the inter-rater reliability of the surgical reviews.

Methods

Of the first 3200 enrolled AREN03B2 patients, a sample of 100 enriched for blood vessel involvement, spill, rupture, and lymph node involvement was selected for analysis. The surgical assessment was then performed independently by two blinded surgical reviewers and compared to the original assessment, which had been completed by another of the committee surgeons. Variables assessed included surgeon-determined local tumor stage, overall disease stage, type of renal procedure performed, presence of tumor rupture, occurrence of intraoperative tumor spill, blood vessel involvement, presence of peritoneal implants, and interpretation of residual disease. Inter-rater reliability was measured using the Fleiss' Kappa statistic two-sided hypothesis tests (Kappa, p-value).

Results

Local tumor stage correlated in all 3 reviews except in one case (Kappa = 0.9775, p < 0.001). Similarly, overall disease stage had excellent correlation (0.9422, p < 0.001). There was strong correlation for type of renal procedure (0.8357, p < 0.001), presence of tumor rupture (0.6858, p < 0.001), intraoperative tumor spill (0.6493, p < 0.001), and blood vessel involvement (0.6470, p < 0.001). Variables that had lower correlation were determination of the presence of peritoneal implants (0.2753, p < 0.001) and interpretation of residual disease status (0.5310, p < 0.001).

Conclusion

The inter-rater reliability of the surgical review is high based on the great consistency in the 3 independent review results. This analysis provides validation and establishes precedent for real-time central surgical review to determine treatment assignment in a risk-based stratagem for multimodal cancer therapy.  相似文献   
100.
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