998 resultados para SRS-2


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Introduction This study investigated the sensitivity of calculated stereotactic radiotherapy and radiosurgery doses to the accuracy of the beam data used by the treatment planning system. Methods Two sets of field output factors were acquired using fields smaller than approximately 1 cm2, for inclusion in beam data used by the iPlan treatment planning system (Brainlab, Feldkirchen, Germany). One set of output factors were measured using an Exradin A16 ion chamber (Standard Imaging, Middleton, USA). Although this chamber has a relatively small collecting volume (0.007 cm3), measurements made in small fields using this chamber are subject to the effects of volume averaging, electronic disequilibrium and chamber perturbations. The second, more accurate, set of measurements were obtained by applying perturbation correction factors, calculated using Monte Carlo simulations according to a method recommended by Cranmer-Sargison et al. [1] to measurements made using a 60017 unshielded electron diode (PTW, Freiburg, Germany). A series of 12 sample patient treatments were used to investigate the effects of beam data accuracy on resulting planned dose. These treatments, which involved 135 fields, were planned for delivery via static conformal arcs and 3DCRT techniques, to targets ranging from prostates (up to 8 cm across) to meningiomas (usually more than 2 cm across) to arterioveinous malformations, acoustic neuromas and brain metastases (often less than 2 cm across). Isocentre doses were calculated for all of these fields using iPlan, and the results of using the two different sets of beam data were evaluated. Results While the isocentre doses for many fields are identical (difference = 0.0 %), there is a general trend for the doses calculated using the data obtained from corrected diode measurements to exceed the doses calculated using the less-accurate Exradin ion chamber measurements (difference\0.0 %). There are several alarming outliers (circled in the Fig. 1) where doses differ by more than 3 %, in beams from sample treatments planned for volumes up to 2 cm across. Discussion and conclusions These results demonstrate that treatment planning dose calculations for SRT/SRS treatments can be substantially affected when beam data for fields smaller than approximately 1 cm2 are measured inaccurately, even when treatment volumes are up to 2 cm across.

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报道了利用重复频率为30HZ,波长为532nm的Nd:YAG倍频激光单次通过抽运硝酸钡(Ba(NO3)2)晶体(晶体由水溶液降温法生长,长度为48mm,横截面为10mm×10mm),获得高效率的一阶(563nm),二阶(599nm)和三阶(639nm)斯托克斯光的实验结果.硝酸钡晶体沿着[110]晶轴方向切割.观测到一、二、三阶斯托克斯光呈锥形环分布,一、二、三阶斯托克斯光的散射外边缘与抽运光轴线间的夹角大小分别为1.7°,3.5°,5.0°.同时也观测到Ba(NO3)2的SRS角度分布与抽运光强度无关.

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The authors conducted a study to define the long-term outcomes and risks of stereotactic radiosurgery (SRS) for pediatric arteriovenous malformations (AVMs).

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Contient : 1 « Advis sur l'histoire genealogique de la maison de France des Srs de Saincte Marthe, envoiez le 4 mars, l'an 1635 » ; 2 « Memoires des chanceliers de France » ; 3 « Annotations sur les Memoires de M. Jean Du Tillet » ; 4 « Observatio de Conradi Salicis, imperatoris, et Giselae, ejus uxoris cognatione » et « de Henrico IV, imperatore » ; 5 « Chronologie des règnes des rois de France des deux premières lignées » ; 6 « Collection de plusieurs extraicts d'histoires, chroniques et tiltres touchant le mariage du roi Philippe Ier avec Bertrade de Montfort, son divorce, et l'excommunication qu'il encourut pour ce faict » ; 7 « Philippe Auguste. Sur la dissolution du mariage du roy Philippes Auguste avec Ingeburge de Dannemark » ; 8 « Memoires pour le Bearn », savoir : a. « Memoires de la souveraineté de Bearn » (fol. 127 à 138); b. « Bearn, ou traicté du Bearn et des seigneurs qui en ont tenu le tiltre » (fol. 139 à 153); c. Les feuillets 144 et 145, 146 à 148, 152 et 153 contiennent trois brouillons de lettres sur le même sujet, et le second est daté du « 1er novembre 1620 »; d. « Memoire des vicomtes de Bearn » (fol. 154-159); e. « Memoire des vicomtes de Bearn » (fol. 160-5) ; f. « Force braves seigneurs » (fol. 166-9); g. « Memoires du Bearn » (fol. 170-8) ; 9 Foix ; 10 Suite des Mémoires concernant le Bearn, savoir : h. « Fors et costumas de Bearn » (fol. 180); i. « Extraict d'un gros inventaire du tresor des cartes de Bearn » (fol. 181); j. Vicomtes de Bearn (fol. 183-4) ; 11 Comtes de Toulouse, chronique en provençal : « Aiso es comtes que ag d'Azam entro al diluvi... Anno Domini MCC LXXV, iij die introitus mensis junii obiit nobilis vir dominus Sicardus Alamanni, cujus anima requiescat in pace » ; 12 Lettre signée : « Gaudineau » et adressée de « Luçon, le 24 may 1620... à M. l'advocat du roy et mayre, à Fontenay » ; 13 Factum contre « defuncte Jeh. de S. Martin, qui par son testament avait violé la coutume de Poitou » ; 14 Vicomtes de Bearn ; 15 « Project de l'origine de Hugues, roy d'Italie » ; 16 Poitou, Guyenne, Toulouse, ou histoire des comtes de Toulouse ; 17 Au feuillet 254 brouillon de lettre; au feuillet 255 dessins de sceaux : a. « S. Raimundi, Dei gra comitis Tolose, march. Provincie »; b. Autre figure, même légende. Dans a, le comte de Toulouse est représenté assis; dans b., il est représenté à cheval. Au feuillet 257 dessins de sceaux : a. « S. Alfonsus, fili. reg. Franc., comes Pict. et Tolose »; b. « S. R. Dalfini, comitis clr. ». Au feuillet 259 dessins de sceaux : a. Sigillum Ademari »; b. contresceau : « comitis Valemtinensis ». Au feuillet 261 dessins de sceaux : a. « S. comitis Provincie »; b. « Sigillum Raimundi Berengeri ». Au feuillet 262 dessins de sceaux : a. « S. comisse, uxoris Bereng., comitis et march. Provincie et comitis Forcalhari »; b. « Arma comitis a Sabaudie et marchis Italie » ; 18 « Mathildis comitissa » ; 19 Hugues, roi d'Italie, et Mathilde, la comtesse ; 20 Les mariages consanguins ; 21 Anthemius, etc., note adressée à l'év. de Poitiers, mise au net « le 16 fevrier 1640 » ; 22 « Regnante Christo », note sur cette formule ; 23 « Memoires pour Mr Du Chasteler-Barlot, contre les quatre tiltres qu'on luy oppose touchant la capitainerie de l'isle de Bouyn » ; 24 Lettre concernant les comtes d'Auvergne ; 25 Lettre ; 26 Lettre sur Chastelaillon et La Rochelle. Date : « A Fontenay le Comte, le 19 mars 1628 » ; 27 Lettre concernant Hugues Capet. Date : « A Paris, ce 7 mars 1633 ». Signé : « Besly » ; 28 « Galliae distributio » ; 29 Note sur la ville de « Vivonne » ; 30 Note sur Thouars et ses vicomtes ; 31 « De Melusine, dame de Lezignan » ; 32 « De S. Hilario Trevirensi » ; 33 Mémoire sur les comtes de Toulouse

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A method of preparation of strontium sulphide phosphors doped with europium is given. Nitrogen laser excited fluorescence emission spectra of these phosphors in the visible region are recorded. A band with line structure in the region 350-430 nm and a new broad band at 460 nm are observed. The splitting pattern for the 6p levels of Eu 2+ are given.

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Excitation and emission spectra of SrS : Mn : Ce phosphors have been studied in detail at various Mn and Ce concentrations. In order to study the effect of external pressure on phosphors, the samples were pretreated under various pressures. Four bands around 470 nm, 530 nm, 310 nm and 620 nm were observed, when the samples were excited with 265 nm radiation. The effect of pressure is to reduce the fluorescence ability of the phosphors, and the luminescence vanishes above O· 1 ton m-2 pressure. The fluorescence ability, however, can be regained on retiring the sample. The emission mechanism has been attributed to two luminescentcenters in the forbidden gap. An appreciable amount of photocurrent has also been observed for the sample.

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Study Design. Prospective clinical case series. Objective. To evaluate the clinical outcome of anterior endoscopic instrumention for scoliosis using the SRS-24 questionnaire and to examine how these scores change over a 2-year follow-up period. Summary of Background Data. Anterior endoscopic instrumentation correction has several advantages compared with open procedures. However, the clinical results of this technique using a validated outcome measure have rarely been reported in the literature. Methods. A total of 83 consecutive patients underwent endoscopic anterior instrumentation performed at a single unit. Patients completed the SRS-24 questionnaire before surgery and at 3, 6, 12, and 24 months after surgery. The SRS-24 scores were compared between each of the follow-up intervals. Results. The pain, general self-image, and function from back condition domains improved after surgery (P < 0.05). Activity level significantly improved between 3 and 6 months, and both function domains improved between 6 and 12 months (P < 0.05). None of the domains increased significantly after 1 year. Conclusions. Endoscopic anterior instrumentation for scoliosis significantly improved pain, self-image, and function. The greatest improvement in function occurred between 6 and 12 months after surgery. The SRS-24 scores at 1 year from surgery may provide a good indicator of patient outcome in the long-term.

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This material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DBI-0620409 and #DEB-9910514. This image is made available for non-commercial or educational use only.

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Anais da Câmara dos Srs. Deputados do Império do Brasil.