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101.
102.
Stefania Milione Isabella Mercurio Paola Melai Veronica Agostinelli Nicola Nante 《The Australian journal of forensic sciences》2017,49(6):679-686
Wastewater analysis is a direct and objective method used to measure human consumption of illicit drugs. In the last few years these have become a new class of environmental contaminants. The aim of our study was the identification of drugs in Tiber River waters. We collected 20 water samples from May to June 2012, at six points of the river: at the source, near Perugia, near Rome and at the mouth. Samples were analysed using gas chromatography with a mass detector. Basic analytes were extracted using the method of Varian Certify. For acidic analytes we proceed to direct extraction using organic solvents. The most detected drug was ecstasy. We also identified traces of methadone, morphine, heroine, methylamphetamine and tetrahydrocannabinol (THC). The highest concentration of cocaine was found near Perugia with a peak in the weekend (4744 ng/ml). Psychoactive substances had constant concentrations in the week. Ecstasy (MDMA) was the most detected drug. The most interesting finding was the increased concentration of cocaine and heroin in waters near Perugia showing the alarming phenomenon of weekend use of these substances. 相似文献
103.
Paola Cassoni Lorenzo Daniele Elena Maldi Luisella Righi Veronica Tavaglione Silvia Novello Marco Volante Giorgio Vittorio Scagliotti & Mauro Papotti 《Histopathology》2009,55(1):20-27
Aims: To study caveolin-1 (Cav-1) expression in metastatic lung carcinomas.
Methods and results: Cav-1 expression was investigated in a series of 121 lung carcinomas and it was shown that 18/121 tumours (14.9%) were Cav-1+. None of the pure bronchioloalveolar carcinomas proved to be positive, vs. 42.8% of the large cell carcinomas (neuroendocrine subtype excluded). Adenocarcinomas (8.5%), large cell neuroendocrine carcinomas (20%) and squamous cell carcinomas (29.6%) displayed an intermediate percentage of positive cases, suggesting a gradient of Cav-1 expression according to tumour histotype-related aggressiveness. Moreover, the percentage of Cav-1+ tumours with distant metastases was almost double that of non-metastatic tumours (17.8% vs. 8.1%), irrespective of the histotype. In 34 tumours metastatic to the brain, primary and secondary lesions were compared and 53% of brain metastases were Cav-1+ vs. 20.6% of primaries, indicating a de novo acquisition of Cav-1 expression. This pattern was exclusive to the brain, as it was not acquired in adrenal metastases. In our series, the presence of epidermal growth factor receptor amplification, determined by fluorescence in situ hybridization, was not related to Cav-1 reactivity.
Conclusions: Cav-1 immunoreactivity in lung carcinoma is histotype-dependent and acquired de novo in brain metastases, suggesting a site-specific phenotypic shift in secondary lesions. 相似文献
Methods and results: Cav-1 expression was investigated in a series of 121 lung carcinomas and it was shown that 18/121 tumours (14.9%) were Cav-1+. None of the pure bronchioloalveolar carcinomas proved to be positive, vs. 42.8% of the large cell carcinomas (neuroendocrine subtype excluded). Adenocarcinomas (8.5%), large cell neuroendocrine carcinomas (20%) and squamous cell carcinomas (29.6%) displayed an intermediate percentage of positive cases, suggesting a gradient of Cav-1 expression according to tumour histotype-related aggressiveness. Moreover, the percentage of Cav-1+ tumours with distant metastases was almost double that of non-metastatic tumours (17.8% vs. 8.1%), irrespective of the histotype. In 34 tumours metastatic to the brain, primary and secondary lesions were compared and 53% of brain metastases were Cav-1+ vs. 20.6% of primaries, indicating a de novo acquisition of Cav-1 expression. This pattern was exclusive to the brain, as it was not acquired in adrenal metastases. In our series, the presence of epidermal growth factor receptor amplification, determined by fluorescence in situ hybridization, was not related to Cav-1 reactivity.
Conclusions: Cav-1 immunoreactivity in lung carcinoma is histotype-dependent and acquired de novo in brain metastases, suggesting a site-specific phenotypic shift in secondary lesions. 相似文献
104.
De la Fuente M Baeza I Guayerbas N Puerto M Castillo C Salazar V Ariznavarreta C F-Tresguerres JA 《Biogerontology》2004,5(6):389-400
The impairment of the immune system with aging, or immunosenescence, appears to contribute to the increased morbidity and mortality of aged subjects. T cell functions and Natural Killer activity seem to be the immune responses most affected by ageing. Since the immune system works more efficiently in females than in males, we have studied the changes of several immune functions with age in rats of both sexes. In addition, we have investigated if ovariectomy, a model of menopause in rats, produces a loss of this gender-related advantage. In the present work, the changes with age (2, 6, 12, 14, 18, 22 and 24 months old) in lymphocyte chemotaxis, T lymphoproliferative response to the mitogen ConA, IL-2 release and Natural Killer activity of cells from axillary nodes and spleen of male and female rats as well as of females ovariectomized at 12 months of age have been studied. An age-related decrease was found in all investigated functions, with a slightly different evolution depending on the immune organ and gender considered. In general, the data obtained show that a certain degree of immunosenescence takes place with age in rats, with males being less immunocompetent than intact age-matched females, but showing an immune response similar to that of ovariectomized animals. 相似文献
105.
Thomas J van Brakel Gil Bolotin L Wiley Nifong André L A J Dekker Maurits A Allessie W Randolph Chitwood Jos G Maessen 《European heart journal》2005,26(13):1321-1326
AIMS: To study the feasibility and electrophysiological efficacy of minimally invasive beating heart ablation of the pulmonary veins (PVs) via a robot-assisted single-sided approach. BACKGROUND: PV isolation by minimally invasive epicardial ablation may offer a new treatment for patients with lone atrial fibrillation (AF). However, complete PV isolation has been shown to be difficult to obtain. METHODS AND RESULTS: In 14 mongrel dogs, robot-assisted epicardial microwave ablation was performed on the beating heart by a single-sided right chest approach. Isolation of all PVs was performed in two steps to study the effect of an incomplete and a complete isolation on AF. AF was studied by random and burst pacing. Incremental pacing was performed to study conduction characteristics across the lesions. Opening of the pericardial reflections, introduction of the catheter and ablation were robotically feasible by a single-sided approach in 11 dogs. The AF duration decreased from 6.6+/-4.1 to 1.3+/-0.8 s (P=0.03) and 1.6+/-1.6 s (P=0.04 compared with control) after incomplete and completed isolation of the PVs. The AF cycle length increased from 134+/-5 to 141+/-5 and 145+/-8 ms (P=0.03) after incomplete and complete isolation, respectively. Several incomplete lesions showed 2:1 exit and/or entrance block during incremental pacing. After complete isolation, AF was no longer inducible from the PVs. CONCLUSION: Epicardial PV isolation can be successfully performed by a single-sided robot-assisted approach. The effect of PV ablation on AF is not an all or none phenomenon. Incomplete isolation already decreases AF duration and lengthens the AF cycle length. However, complete isolation is necessary to prevent AF induction by triggering from the isolated area. 相似文献
106.
107.
Domenico G. Della Rocca MD Michele Magnocavallo MD Veronica N. Natale MPH Carola Gianni MD PhD Sanghamitra Mohanty MD Chintan Trivedi MD MPH Carlo Lavalle MD Giovanni B. Forleo MD PhD Nicola Tarantino MD Jorge Romero MD Xiadong Zhang MD Mohamed Bassiouny MD Amin Al-Ahmad MD David J. Burkhardt MD Joseph G. Gallinghouse MD Javier E. Sanchez MD Rodney P. Horton MD Luigi Di Biase MD PhD Andrea Natale MD 《Journal of cardiovascular electrophysiology》2021,32(9):2441-2450
108.
109.
Brian D. Wright Michael C. Deblock Patrick O. Wagers Ernest Duah Nikki K. Robishaw Kerri L. Shelton Marie R. Southerland Michael A. DeBord Kortney M. Kersten Lucas J. McDonald Jason A. Stiel Matthew J. Panzner Claire A. Tessier Sailaja Paruchuri Wiley J. Youngs 《Medicinal chemistry research》2015,24(7):2838-2861