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21.
Mutations in the tyrosine kinase domain of the epidermal growth factor receptor in non-small cell lung cancer. 总被引:4,自引:0,他引:4
Sei Hoon Yang Leah E Mechanic Ping Yang Maria Teresa Landi Elise D Bowman Jason Wampfler Daoud Meerzaman Kyeong Man Hong Felicia Mann Tatiana Dracheva Junya Fukuoka William Travis Neil E Caporaso Curtis C Harris Jin Jen 《Clinical cancer research》2005,11(6):2106-2110
We evaluated somatic genetic alterations in the kinase domain of the EGFR gene in the tumors of 219 non-small cell lung cancer patients of primarily Caucasian and African American origins. We identified 26 patients (12%) whose tumors had a mutation in the EGFR gene, and 11 (5%) patients carried novel genomic variations consistent with germ-line polymorphisms. All but one mutation were identified in Caucasian patients affected with adenocarcinoma. EGFR mutations were more frequent in women and in nonsmokers, but a significant portion of the affected patients were men (12 of 26) and current or past smokers accounted for half of the patients affected (13 of 26). Screening subjects with EGFR mutations may identify patients whose tumors could respond to targeted therapy using tyrosine kinase inhibitors. 相似文献
22.
Aleksandr Kolchin Dmitrii Shuleiko Mikhail Martyshov Aleksandra Efimova Leonid Golovan Denis Presnov Tatiana Kunkel Victoriia Glukhenkaya Petr Lazarenko Pavel Kashkarov Stanislav Zabotnov Sergey Kozyukhin 《Materials》2022,15(10)
Ge2Sb2Te5 (GST225) looks to be a promising material for rewritable memory devices due to its relatively easy processing and high optical and electrophysical contrast for the crystalline and amorphous phases. In the present work, we combined the possibilities of crystallization and anisotropic structures fabrication using femtosecond laser treatment at the 1250 nm wavelength of 200 nm thin amorphous GST225 films on silicon oxide/silicon substrates. A raster treatment mode and photoexcited surface plasmon polariton generation allowed us to produce mutually orthogonal periodic structures, such as scanline tracks (the period is 120 ± 10 μm) and laser-induced gratings (the period is 1100 ± 50 nm), respectively. Alternating crystalline and amorphous phases at the irradiated surfaces were revealed according to Raman spectroscopy and optical microscopy studies for both types of structures. Such periodic modulation leads to artificial optical and electrophysical anisotropy. Reflectance spectra in the near infrared range differ for various polarizations of probing light, and this mainly results from the presence of laser-induced periodic surface structures. On the other hand, the scanline tracks cause strong conductivity anisotropy for dc measurements in the temperature range of 200–400 K. The obtained results are promising for designing new GST225-based memory devices in which anisotropy may promote increasing the information recording density. 相似文献
23.
Sandra Lepak-Kuc Katarzyna Wasilewska Daniel Janczak Tatiana Nowicka Magorzata Jakubowska 《Materials》2022,15(10)
In this study, the extremely important and difficult topic of flexographic printing on a heat-shrinkable substrate was taken up. Six commercially available, electrically conductive inks based on silver, copper and graphite nanoparticles were selected and tested upon their applicability for printing on the temperature-sensitive PET material. As a printing substrate, the one-direction heat-shrinkable PET film, with a maximum shrinkage of 78%, was selected. All of the examined inks were subjected to the printing process throughout three different anilox line screens. The tested inks, along with the electric paths printed with them, were subjected to various tests. The main parameters were evaluated, such as printability combined with the rheology tests and ink adhesion to the examined PET substrate together with the electrical conductivity before and after the shrinkage. 相似文献
24.
Alexandre de Matos Soeiro Bruno Biselli Tatiana C.A.T. Leal Aline Siqueira Bossa Maria Cristina Csar Srgio Jallad Priscila Gherardi Goldstein Patrícia Oliveira Guimares Carlos Vicente Serrano Jr Cesar Higa Nomura Dbora Nakamura Carlos Eduardo Rochitte Paulo Rogrio Soares Múcio Tavares de Oliveira Jr. 《Arquivos brasileiros de cardiologia》2022,118(5):894
BackgroundCoronary tomography angiography (CTA) has been mainly used for chest pain evaluation in low-risk patients, and few data exist regarding patients at intermediate risk.ObjectiveTo evaluate the performance of serial measures of sensitive troponin and CTA in intermediate-risk patients.MethodsA total of 100 patients with chest pain, TIMI risk scores of 3 or 4, and negative troponin were prospectively included. All patients underwent CTA and those with coronary stenosis ≥ 50% were referred to invasive coronary angiography. Patients with coronary lesions <50% were discharged and contacted 30 days later by a telephone call to assess clinical outcomes. Outcomes were hospitalization, death, and myocardial infarction at 30 days. The comparison between methods was performed by Kappa agreement test. The performance of troponin measures and CTA for detecting significant coronary lesions and clinical outcomes was calculated. Results were considered statistically significant when p < 0.05.ResultsCoronary stenosis ≥ 50% on CTA was found in 38% of patients and significant coronary lesions on coronary angiography were found in 31 patients. Two clinical events were observed. Kappa agreement analysis showed low agreement between troponin measures and CTA in the detection of significant coronary lesions (kappa = 0.022, p = 0.78). The performance of CTA for detecting significant coronary lesions on coronary angiography or for predicting clinical events at 30 days was better than sensitive troponin measures (accuracy of 91% versus 60%).ConclusionCTA performed better than sensitive troponin measures in the detection of significant coronary disease in patients with chest pain and intermediate risk for cardiovascular events. 相似文献
25.
Tsyvian PB Markova TV Mikhailova SV Hop WC Wladimiroff JW 《European journal of obstetrics, gynecology, and reproductive biology》2008,140(1):33-37
OBJECTIVE: To determine left ventricular isovolumic relaxation time (LV IRT) in normally developing and growth restricted fetuses (FGR) as an indicator of fetal cardiac afterload and neonatal systolic blood pressure. STUDY DESIGN: A prospective longitudinal study in 124 normally developing and 47 growth restricted fetuses (FGR). LV IRT, fetal heart rate (FHR) and umbilical artery pulsatility index (PI) were determined at 2-3 week intervals starting at 22-26 weeks of gestation until delivery. Renin and angiotensin I levels were measured by radioimmunoassay in umbilical venous blood after delivery. Systolic blood pressure was measured at day 1 and day 5 of postnatal life. To evaluate the association between LV IRT, gestational age and FHR, bivariate regression analyses were performed. RESULTS: Mean LV IRT (62+/-8ms) was 29 percent longer in FGR as compared to the normal subset (47+/-6ms) at all gestational ages (p<0.001). Mean postnatal active plasma renin level (7.78+/-S.D. 1.03ng/ml) and postnatal angiotensin I level (4.21+/-0.70ng/ml) in the FGR subset were significantly higher (p<0.001) than in the normal subset (4.81+/-1.04ng/ml, renin and 2.69+/-0.44ng/ml, angiotensin I). There was a significant difference (p<0.01) in systolic blood pressure between the two subsets on postnatal day 1 (FGR 52+/-6mmHg vs. normal 46+/-4mmHg) and day 5 (FGR 76+/-5mmHg vs. normal 60+/-6mmHg). CONCLUSION: Left ventricular isovolumic relaxation time may act as a sensitive index of increased arterial afterload in the growth retarded fetus and may herald raised systolic blood pressure in the early neonatal period. 相似文献
26.
Jain S Zharikova OL Ravindran S Nanovskya TN Mattison DR Hankins GD Ahmed MS 《American journal of perinatology》2008,25(3):169-174
The aim of this investigation was to determine the metabolism of glyburide (GL) by microsomes prepared from placentas obtained from uncomplicated pregnancies (UP), women with gestational diabetics (GD) on a diabetic diet, and those on a diet and GL. Term placentas were obtained from UP and GD. Crude microsomal fractions were prepared by differential centrifugation and stored at -80 degrees C. The activity of the microsomes in metabolizing glyburide to the trans-4-hydroxycyclohexyl glyburide (THCGL) and cis-3-hydroxycyclohexyl glyburide (CHCGL) was determined and quantified using high-performance liquid chromatography-mass spectrometer (HPLC-MS). The activity of the placental microsomes varied widely between individual placentas in each group. The median values (pmol.mg (-1) P.min (-1)) for the rates of THCGL formation were 0.34, 0.3, and 0.23 for placentas of UP, GD on diet, and GD on GL and a diet, respectively. The median values for CHCGL formation were 0.13 for UP, 0.11 for GD on a diet, and 0.10 (pmol.mg (-1) P.min (-1)) for GD on GL and a diet. A pool of individual microsomal fractions from each group was prepared and its activity revealed the following: greater formation of THCGL in the UP (0.36 +/- 0.10) than GD (0.22 +/- 0.03) ( P = 0.058 for GD on a diet, 0.04 for GD on GL). There was greater formation of CHCGL in UP (0.26 +/- 0.04) than GD (0.12 +/- 0.003) ( P < 0.006). There was no difference in GD on a diet and GD on GL plus diet. We concluded that the apparent differences in the formation of metabolites may be statistically significant, but it is unlikely to be of physiological importance, given the sample size and other experimental factors. Therefore, a more comprehensive investigation is underway. 相似文献
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29.
Zusammenfassung Die Abhandlung ist der experimentellen Untersuchung des rhythmischen Oktaven-Klavieranschlags, die von den Autoren in den Jahren 1927/28 mittels der kymozyklographischen Methode an hervorragenden Pianistenvirtuosen durchgeführt wurde, gewidmet. Der Untersuchung wurden monotone Aufeinanderfolgerungen der Oktaven unterworfen: 1. in cresc.-dimin. und 2. in acceler.-rallent.Nach den erhaltenen Photoaufzeichnungen wurden studiert: 1. die Bewegungen der rechten Armteile (Ober-, Unterarm, Hand), 2. Änderungen der Gelenkwinkel, 3. die Momente der Resultanten der Muskelspannungen im Schulter-, dem Ellenbogen- und Handgelenk. Die Untersuchung hat die Möglichkeit gegeben, eine typische Form des Verlaufs des rhythmischen Oktavenanschlags festzustellen und seine genaue Beschreibung zu geben.Die Versuche der Änderung der Anschlagskraft haben gezeigt, daß die Bewegungsdynamik sich in Abhängigkeit von der Anschlagskraft nur quantitativ, bei konstanter Konstruktion, verändert.Die Versuche der Tempoänderung haben gezeigt, daß die Anschlagskonstruktion abhängig vom Tempo sich wesentlich verändert. Bei langsamen Tempos besteht die Bewegung aus isolierten Impulsen, bei mittleren entspricht sie den Schwingungen des zusammengesetzten Pendels, bei den schnellsten Tempos geht sie in erzwungene elastische Schwingungen vom Typus des einfachen Pendels bei elastisch-passivem Handgelenk über.Die Versuche haben festgestellt, daß bei allen Bewegungen der studierten Art in den Tempos über 3 Anschläge in der Sekunde das Fallen der Hand infolge ihres Gewichtes (Gewichtsanschlag) nicht stattfindet und aus rein mechanischen Gründen nicht stattfinden kann. In den langsamsten Tempos kommt es manchmal vor, jedoch bedeutend seltener, als man es theoretisch erwarten könnte.Die Abhandlung stellt eine erste Arbeit von der Serie, die von der Klaviersektion des St. Inst. f. Musikwissenschaft durchgeführt wird, vor, und die dem Studium des Klavieranschlags: 1. bei komplizierten Rhythmen, 2. bei Anfängern und fortgeschrittenen Lehrlingen und 3. hinsichtlich des Vergleichs der Klavierspieler verschiedener Schulen und Individualitäten gewidmet ist. 相似文献
30.
Influence of a high-fat diet on gut microbiota, intestinal permeability and metabolic endotoxaemia 总被引:2,自引:0,他引:2
Moreira AP Texeira TF Ferreira AB do Carmo Gouveia Peluzio M de Cássia Gonçalves Alfenas R 《The British journal of nutrition》2012,108(5):801-809
Lipopolysaccharide (LPS) may play an important role in chronic diseases through the activation of inflammatory responses. The type of diet consumed is of major concern for the prevention and treatment of these diseases. Evidence from animal and human studies has shown that LPS can diffuse from the gut to the circulatory system in response to the intake of high amounts of fat. The method by which LPS move into the circulatory system is either through direct diffusion due to intestinal paracellular permeability or through absorption by enterocytes during chylomicron secretion. Considering the impact of metabolic diseases on public health and the association between these diseases and the levels of LPS in the circulatory system, this review will mainly discuss the current knowledge about high-fat diets and subclinical inflammation. It will also describe the new evidence that correlates gut microbiota, intestinal permeability and alkaline phosphatase activity with increased blood LPS levels and the biological effects of this increase, such as insulin resistance. Although the majority of the studies published so far have assessed the effects of dietary fat, additional studies are necessary to deepen the understanding of how the amount, the quality and the structure of the fat may affect endotoxaemia. The potential of food combinations to reduce the negative effects of fat intake should also be considered in future studies. In these studies, the effects of flavonoids, prebiotics and probiotics on endotoxaemia should be investigated. Thus, it is essential to identify dietetic strategies capable of minimising endotoxaemia and its postprandial inflammatory effects. 相似文献