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991.
Luis A. Pérez Romasanta María José García Velloso Antonio López Medina 《Reports of Practical Oncology and Radiotherapy》2013,18(6):376-382
Functional imaging and its application to radiotherapy (RT) is a rapidly expanding field with new modalities and techniques constantly developing and evolving. As technologies improve, it will be important to pay attention to their implementation. This review describes the main achievements in the field of head and neck cancer (HNC) with particular remarks on the unsolved problems. 相似文献
992.
Adela Poitevin-Chacón José Hinojosa-Gómez 《Reports of Practical Oncology and Radiotherapy》2013,18(2):57-60
Aim
This survey is performed to learn about the structure of radiotherapy in México.Background
Radiation oncology practice is increasing because of the higher incidence of cancer. There is no published data about radiotherapy in México.Materials and methods
A questionnaire was sent to the 83 registered centers in the database of the Mexican regulatory agency. One out of the 32 states has no radiotherapy. 27 centers from 14 states provided their answers.Results
829 patients are treated annually with any radiotherapy modality in each center. Two centers have one cobalt machine, 7 have a cobalt and a linac and 10 have more than one linac. Five centers use 2D planning systems, 22 use 3D; 9, conventional simulators; 22, CT based simulation, and 1 center has no simulation. Most of the centers verify beams with films, electronic portal image devices and cone beam CTs are also used. Intensity modulated and image guided radiotherapy are performed in 5 states. Breast, prostate, cervix, lung, rectum and head and neck cancer are the six most common locations. There are 45 public and 38 private centers, 2 dedicated to children. Two gamma knife units, 5 Novalis systems, 1 tomotherapy and 2 cyberknife machines are working. All centers have at least one radiation oncologist, one physicist and one radiotherapist.Conclusions
Definitive conclusions cannot be drawn from this limited feedback due to a low participation of centers. This survey about radiotherapy in Mexico shows the heterogeneity of equipment as well as medical and technical staff in the whole country. 相似文献993.
P. Madejón L. Ciadamidaro T. Marañón J. M. Murillo 《International journal of phytoremediation》2013,15(6):602-614
Phytostabilization aims to immobilize soil contaminants using higher plants. The accumulation of trace elements in Populus alba leaves was monitored for 12 years after a mine spill. Concentrations of As and Pb significantly decreased, while concentrations of Cd and Zn did not significantly over time. Soil concentrations extracted by CaCl2 were measured by ICP-OES and results of As and Pb were below the detection limit. Long-term biomonitoring of soil contamination using poplar leaves was proven to be better suited for the study of trace elements. Plants suitable for phytostabilization must also be able to survive and reproduce in contaminated soils. Concentrations of trace elements were also measured in P. alba fruiting catkins to determine the effect on its reproduction potential. Cadmium and Zn were found to accumulate in fruiting catkins, with the transfer coefficient for Cd significantly greater than Zn. It is possible for trace elements to translocate to seed, which presents a concern for seed germination, establishment and colonization. We conclude that white poplar is a suitable tree for long-term monitoring of soil contaminated with Cd and Zn, and for phytostabilization in riparian habitats, although some caution should be taken with the possible effects on the food web.
Supplemental materials are available for this article. Go to the publisher's online edition of International Journal of Phytoremediation to view the supplemental file. 相似文献
994.
José Fiandor María Teresa García-López Federico G. De las Heras Paloma P. Méndez-Castrillón Carmen Gil-Fernández Sara Pérez 《Nucleosides, nucleotides & nucleic acids》2013,32(2):257-271
Abstract A series of 5′-O-[[[[(alkyl)oxy]carbonyl] amino] sulfonyl] uridines have been synthesized by reaction of cyclohexanol, palmityl alcohol, 1,2-di-O-benzoylpropanetriol and 2,3,4,6-tetra-O-benzoyl-L-glucopyranose with chlorosulfonyl isocyanate and 2,3′-O-isopropylidene-uridine. Another series of 5′-O-(N-ethyl and N-isopropylsulfamoyl) uridines have been prepared by reaction of 2′,3′-O-isopropylidene and 2′,3′-di-O-acetyluridine with N-ethylsulfamoyl and N-isopropylsulfamoyl chlorides. All compounds were tested against HSV-2, VV, SV and ASFV viruses. 2′,3′-Di-O-acetyl-5′-O-(N-ethyl and N-isopropylsulfamoyl) uridine showed significant activities against HSV-2. 5′-O-[[[[(2,3,4,6-Tetra-O-benzoyl-β-L-glucopyranosyl)oxy]carbonyl]amino] sulfonyl]-2′,3′-O-isopropylideneuridine was very active against ASFV. 相似文献
995.
T. Spasokoukotskaja Z. Csapó S. Virga M. Sasvári-Székely M. Staub G. Keszler 《Nucleosides, nucleotides & nucleic acids》2013,32(9-11):1181-1184
Previously, we have found that activation of deoxycytidine kinase elicited by various DNA-damaging chemical agents could be prevented by BAPTA-AM, a cell-permeable calcium chelator or by pifithrin-α, a pharmacological inhibitor of p53. Here, we show that stimulation of deoxycytidine kinase by UV-light also is calcium-dependent and pifithrin-α-sensitive in tonsillar lymphocytes, while thymidine kinase 1 activity is stabilised in the presence of BAPTA-AM. Importantly, both UV-irradiation and calcium chelation decreased the incorporation of labelled deoxycytidine and thymidine into DNA. Pifithrin-alpha dramatically reduced the labelling of both the nucleotide and DNA fractions, possibly due to inhibition of transmembrane nucleoside transport. 相似文献
996.
Lászió Puskás József Czombos Sándor Bottka 《Nucleosides, nucleotides & nucleic acids》2013,32(3-5):967-968
Abstract Phosphoramidite derivative of 1,4-diamino antraquinone was synthesized, characterized, and incorporated into oligonucleotides. Intercalative interaction between the dye and the nucleic acid was confirmed by CD spectroscopy. 相似文献
997.
S. Velázquez V. Tuñón M. L. Jimeno M. J. Pérez-Pérez A. San-Félix C. Chamorro 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):1029-1030
Abstract Novel series of [ddN]-(CH2)n-[TSAO-T] heterodimers have been prepared and tested for their anti-HIV-1 and HIV-2 activity. The most active compound of this series was the [d4T]-(CH2)3-[TSAO-T] heterodimer (EC50 = 0.018 ± 0.03 μM). 相似文献
998.
J. G. Puig E. de Miguel M. C. Castillo A. López Rocha M. A. Martínez R. J. Torres 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):592-595
Thirty-five patients (23 males) with asymptomatic hyperuricemia for at least two years underwent two-dimensioal ultrasonography of knees and ankles. Urate deposits (tophi) in tendons, synovium, and other soft tissues were detected in 12 patients (34%). Increased vascularity (inflammation) was evident in 8 of these patients (23%). Tophi were more frequently found in knees than in ankles and were especially prevalent in the distal patellar tendon. The presence of tophi was unrelated to the known duration of hyperuricemia (mean, 5 years). Ultrasonography allows detection of tophi and inflammation in a third and in a fourth, respectively, of asymptomatic hyperuricemic patients. 相似文献
999.
G. Negrón B. Quiclet-Sire Y. Diaz R. Gaviño R. Cruz 《Nucleosides, nucleotides & nucleic acids》2013,32(7):1539-1543
Abstract The preparation of 3-alkyl D4T derivatives has been carried out starting from the corresponding 5′-O-t-butyldimethylsilyl-3′-O-methanesulfonylthymidine 2 by way of deprotection-elimination and succesive alkylation reactions. 相似文献
1000.
Anna Maria Aviñó Adrian Mayordomo Ruth Espuny Montse Bach Ramon Eritja 《Nucleosides, nucleotides & nucleic acids》2013,32(7):1613-1617
Abstract The preparation of N2, N2-dimethylguanosine is described. The use of the 2-(p-nitrophenyl)ethyl group instead of the benzyl protecting group for the O6 position of the guanine ring resulted in better yields and shorter protocols. 相似文献