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41.
Ishiguro A; Spirin KS; Shiohara M; Tobler A; Gombart AF; Israel MA; Norton JD; Koeffler HP 《Blood》1996,87(12):5225-5231
42.
Spread of X inactivation on chromosome 15 is associated with a more severe phenotype in a girl with an unbalanced t(X; 15) translocation 下载免费PDF全文
43.
Anthony H. Kashou Sarah LoCoco Trevon D. McGill Christopher M. Evenson Abhishek J. Deshmukh David O. Hodge Daniel H. Cooper Sandeep S. Sodhi Phillip S. Cuculich Samuel J. Asirvatham Peter A. Noseworthy Christopher V. DeSimone Adam M. May 《Annals of noninvasive electrocardiology》2022,27(1)
BackgroundAutomated wide complex tachycardia (WCT) differentiation into ventricular tachycardia (VT) and supraventricular wide complex tachycardia (SWCT) may be accomplished using novel calculations that quantify the extent of mean electrical vector changes between the WCT and baseline electrocardiogram (ECG). At present, it is unknown whether quantifying mean electrical vector changes within three orthogonal vectorcardiogram (VCG) leads (X, Y, and Z leads) can improve automated VT and SWCT classification.MethodsA derivation cohort of paired WCT and baseline ECGs was used to derive five logistic regression models: (i) one novel WCT differentiation model (i.e., VCG Model), (ii) three previously developed WCT differentiation models (i.e., WCT Formula, VT Prediction Model, and WCT Formula II), and (iii) one “all‐inclusive” model (i.e., Hybrid Model). A separate validation cohort of paired WCT and baseline ECGs was used to trial and compare each model''s performance.ResultsThe VCG Model, composed of WCT QRS duration, baseline QRS duration, absolute change in QRS duration, X‐lead QRS amplitude change, Y‐lead QRS amplitude change, and Z‐lead QRS amplitude change, demonstrated effective WCT differentiation (area under the curve [AUC] 0.94) for the derivation cohort. For the validation cohort, the diagnostic performance of the VCG Model (AUC 0.94) was similar to that achieved by the WCT Formula (AUC 0.95), VT Prediction Model (AUC 0.91), WCT Formula II (AUC 0.94), and Hybrid Model (AUC 0.95).ConclusionCustom calculations derived from mathematically synthesized VCG signals may be used to formulate an effective means to differentiate WCTs automatically. 相似文献
44.
Increased release of interleukin-1 from mouse peritoneal macrophages in vitro after cisplatin treatment 总被引:3,自引:0,他引:3
The supernatants collected from cis-platin (2 micrograms, 5 micrograms, 10 micrograms, treated macrophage monolayers enhance the proliferation of thymocytes by a submitogenic concentration of con A (1 microgram/ml). The supernatants collected from the untreated macrophage monolayers show a gradual ten fold increase in the interleukin-1 (IL-1) activity during 30 min to 48 h incubation at 37 degrees C. Supernatants collected from macrophage monolayers treated with 2 micrograms/ml of cis-platin show only a marginal increase in IL-1 activity as compared to untreated monolayers. However, compared to controls, 30 to 40 fold increases in IL-1 activity were measured in supernatants collected from the macrophage monolayers incubated with 5, 10 and 20 micrograms/ml cis-platin at 37 degrees C. The IL-1 activity in supernatants collected from macrophage monolayers treated with cis platin and LPS are also compared. 相似文献
45.
Shovlin CL Sodhi V McCarthy A Lasjaunias P Jackson JE Sheppard MN 《BJOG : an international journal of obstetrics and gynaecology》2008,115(9):1108-1115
Objectives Hereditary haemorrhagic telangiectasia (HHT) affects 1 in 5–8000 individuals. Pregnancy outcomes are rarely reported. The major reason is that most women do not have their HHT diagnosed prior to pregnancy. Using a large well-characterised series, we studied all pregnancies known to have occurred in HHT-affected women, whether or not their diagnosis was known at the time of pregnancy. Our aim was to estimate rates and types of major complications of HHT in pregnancy, to guide management decisions.
Design Cohort study, with prospective, retrospective and familial components.
Setting/Population Tertiary referral centre population.
Methods All 262 pregnancies in the 111 women with HHT and pulmonary arteriovenous malformations (PAVMs) reviewed between 1999 and 2005 were studied. Eighty-two women (74%) did not have a diagnosis of HHT/PAVM at the time of pregnancy. 222 pregnancies in their 86 HHT-affected relatives were also studied.
Main outcome measures PAVM bleed, stroke and maternal death.
Results Thirteen women experienced life-threatening events during pregnancy: 1.0% (95% CI 0.1–1.9) of pregnancies resulted in a major PAVM bleed; 1.2% (0.3–2.2%) in stroke (not all were HHT related); and 1.0% (0.13–1.9%) in maternal death. All deaths occurred in women previously considered well. In women experiencing a life-threatening event, prior awareness of HHT or PAVM diagnosis was associated with improved survival ( P = 0.041, Fisher's exact test).
Conclusions Most HHT pregnancies proceed normally. Rare major complications, and improved survival outcome following prior recognition, means that pregnancy in a woman with HHT should be considered high risk. Recommendations for pregnancy management are provided. 相似文献
Design Cohort study, with prospective, retrospective and familial components.
Setting/Population Tertiary referral centre population.
Methods All 262 pregnancies in the 111 women with HHT and pulmonary arteriovenous malformations (PAVMs) reviewed between 1999 and 2005 were studied. Eighty-two women (74%) did not have a diagnosis of HHT/PAVM at the time of pregnancy. 222 pregnancies in their 86 HHT-affected relatives were also studied.
Main outcome measures PAVM bleed, stroke and maternal death.
Results Thirteen women experienced life-threatening events during pregnancy: 1.0% (95% CI 0.1–1.9) of pregnancies resulted in a major PAVM bleed; 1.2% (0.3–2.2%) in stroke (not all were HHT related); and 1.0% (0.13–1.9%) in maternal death. All deaths occurred in women previously considered well. In women experiencing a life-threatening event, prior awareness of HHT or PAVM diagnosis was associated with improved survival ( P = 0.041, Fisher's exact test).
Conclusions Most HHT pregnancies proceed normally. Rare major complications, and improved survival outcome following prior recognition, means that pregnancy in a woman with HHT should be considered high risk. Recommendations for pregnancy management are provided. 相似文献
46.
47.
腺病毒载体介导的PML生长抑制因子对前列腺癌细胞生长和致瘤能力的抑制效果 总被引:1,自引:0,他引:1
为探讨用腺病毒载体携带PML(PromyelocyticLeukemia)基因作为前列腺癌基因治疗的可能性,应用重组人携带PML基因腺病毒(AdPML)感染培养的前列腺癌细胞,观察表达PML蛋白的癌细胞与对照组癌细胞的体外生长和裸鼠体内致瘤能力变化,对荷瘤裸鼠瘤体周围注射AdPML,观察治疗组和对照组肿瘤生长的变化。结果显示,感染AdPML的前列腺癌细胞体外生长和裸鼠体内致瘤能力明显下降,荷瘤裸鼠瘤体周围注射AdPML后肿瘤生长速度明显减慢。证实了PML是一种生长抑制因子,提示其可能被应用于前列腺癌的基因治疗研究 相似文献
48.
49.
Background
Despite extensive research, the five-year survival rate of oral squamous cell carcinoma (OSCC) patients has not improved. Effective treatment of OSCC requires the identification of molecular targets and signaling pathways to design appropriate therapeutic strategies. Several genes from the mTOR signaling pathway are known to be dysregulated in a wide spectrum of cancers. However, not much is known about the involvement of this pathway in tumorigenesis of OSCC. We therefore investigated the role of the tumor suppressor genes, TSC1 and TSC2, and other members of this pathway in tumorigenesis of OSCC. 相似文献50.
Effects of positive and negative pressure ventilation on cerebral blood volume of newborn infants 总被引:3,自引:0,他引:3
KS Palmer SA Spencer YABD Wickramasinghe T Wright DP Southall P Rolfe 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(2):132-139
The effects of intermittent positive airway and continuous negative extrathoracic pressure ventilation on cerebral blood volume in preterm infants were studied using near infrared spectroscopy. In 12 infants continuous negative extrathoracic pressure caused a median decrease in cerebral blood volume of 0.14ml/100ml brain (95% confidence intervals (CI) 0.035–0.280) compared with no respiratory support. Oxygenated and deoxygenated haemoglobin also decreased, implying increased venous drainage as the main effect. In 17 infants intermittent positive pressure ventilation also caused a median reduction in cerebral blood volume of 0.06 ml/100 ml brain (95% CI 0.010–0.115) compared with endotracheal positive airway pressure. Deoxygenated haemoglobin increased by 0.07 ml/100 ml brain (95% CI 0.010–0.100) while oxygenated haemoglobin decreased by O.lOml/lOOml brain (95% CI 0.005–0.175). The increase in deoxygenated haemoglobin implies decreased venous drainage and the decrease in oxygenated haemoglobin implies that other factors may also be significant. Heart rate, blood pressure and oxygen saturation were monitored continuously and remained stable. 相似文献