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21.
Use of stereotactic PET images in dosimetry planning of radiosurgery for brain tumors: clinical experience and proposed classification. 总被引:13,自引:0,他引:13
Marc Levivier Nicolas Massager David Wikler José Lorenzoni Salvador Ruiz Daniel Devriendt Philippe David Fran?oise Desmedt Stéphane Simon Paul Van Houtte Jacques Brotchi Serge Goldman 《Journal of nuclear medicine》2004,45(7):1146-1154
We developed a technique that allows the routine integration of PET in stereotactic neurosurgery, including radiosurgery. We report our clinical experience with the combined use of metabolic (i.e., PET) and anatomic (i.e., MRI and CT) images for the radiosurgical treatment of brain tumors. We propose a classification describing the relative role of the information provided by PET in this multimodality image-guided approach. METHODS: Between December 1999 and March 2003, 57 patients had stereotactic PET as part of their image acquisition for the planning of gamma knife radiosurgery. Together with stereotactic MRI and CT, stereotactic PET images were acquired on the same day using either (18)F-FDG or (11)C-methionine. PET images were imported in the planning software for the radiosurgery dosimetry, and the target volume was defined using the combined information of PET and MRI or CT. To analyze the specific contribution of the PET findings, we propose a classification that reflects the strategy used to define the target volume. RESULTS: The patients were offered radiosurgery with PET guidance when their tumor was ill-defined and we anticipated some limitation of target definition on MRI alone. This represents 10% of the radiosurgery procedures performed in our center during the same period of time. There were 40 primary brain lesions, 7 metastases, and 10 pituitary adenomas. Abnormal PET uptake was found in 62 of 72 targets (86%), and this information altered significantly the MRI-defined tumor in 43 targets (69%). CONCLUSION: The integration of PET in radiosurgery provides additional information that opens new perspectives for the optimization of the treatment of brain tumors. 相似文献
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PURPOSE: To assess the dose-dependent effect of low concentrations of isoflurane on respiratory mechanics in normal subjects. METHODS: We studied 12 non-premedicated ASA I patients scheduled for lower abdominal or extremity surgery. After thiopental 5-7 mg*kg(-1) iv and succinylcholine 1 mg x kg(-1) iv, the trachea was intubated and an esophageal balloon was placed optimally by the occlusion test. After introduction of N(2)O and muscle paralysis with vecuronium, we studied 0, 0.6, 0.9 and 1.2% isoflurane. We recorded flow (F), airway opening and esophageal pressures. Signals were amplified, filtered, sampled at 100 Hz, and then fed in a 12-bit analogue-digital converter in a personal computer. Data were collected and analyzed using LABDAT and ANADAT software. Signals were acquired for 60-90 sec during mechanical ventilation (10 mL x kg(-1), 10 breaths x min(-1), I:E ratio 1:2). We estimated respiratory system (RS), lung (L) and chest wall (W) dynamic elastance (E) and resistance (R) by P(t) = EV(T)(t) + RF(t) + K, where t is time, V(T) tidal volume from integration of F, and K an estimation of end-expiratory pressure. ANOVA was used for comparing the basal state with the three concentrations. RESULTS: E and R were statistically lower at 0.6, 0.9 and 1.2% compared to basal values for RS, L and W. Concentrations equal to or higher than 0.6% did not further change respiratory mechanics, except for E(L1.2) compared to E(L0.6,) 12.37 +/- 5.72 and 13.52 +/- 5.64 cm H(2)O.L(-1), respectively. CONCLUSION: Isoflurane concentrations between 0.6-1.2% are not associated to a dose-dependent effect on respiratory mechanics. 相似文献
25.
Michel A. Ghossain Jean-Noël Buy Alain Ruiz Denis Jacob Catherine Sciot Danile Hugol Dominique Vadrot 《Journal of magnetic resonance imaging : JMRI》1998,8(6):1203-1206
A case of hyperreactio luteinalis in an otherwise normal pregnancy is reported. Ascites was present, but no peritoneal implants or adenopathy were seen. Findings that would have suggested the correct diagnosis are the symmetrical and bilateral pattern of the mass, as well as the rather uniform size of the loculi, which were 1 to 3 cm in diameter. 相似文献
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The role of Serratia marcescens porins in antibiotic resistance 总被引:1,自引:0,他引:1
Ruiz N Montero T Hernandez-Borrell J Viñas M 《Microbial drug resistance (Larchmont, N.Y.)》2003,9(3):257-264
The outer membrane permeability of Serratia marcescens was studied by comparing porin-deficient mutants with their parental strains. Omp1-deficient strains were selected by moxalactam resistance, whereas mutants lacking the Omp2 porin were obtained by experimental infection with the SMP2 phage, whose primary receptor is the Omp2 porin. The role of porins was demonstrated in quinolone accumulation assays, where semiquantitative differences in accumulation were observed. Permeability coefficients to cephaloridine of Omp1 mutants were determined and compared with those of the parental strain. The clinical isolates S. marcescens HCPR1 and 866 showed 30- to 200-fold reduced permeability coefficients when Omp1 porin was absent. 相似文献
28.
Tortoriello DV; McGovern PG; Colon JM; Loughlin J; Santoro N 《Human reproduction (Oxford, England)》1998,13(11):3005-3008
We report an instance of critical ovarian hyperstimulation syndrome in a
highly responsive in-vitro fertilization patient despite the preventive
measure of a 4 day 'coast' interval during which no gonadotrophins were
administered while gonadotrophin-releasing hormone agonist therapy
continued until serum oestradiol concentrations fell below 3000 pg/ml.
相似文献
29.
Differences in virulence factors among clinical isolates of Escherichia coli causing cystitis and pyelonephritis in women and prostatitis in men 下载免费PDF全文
Ruiz J Simon K Horcajada JP Velasco M Barranco M Roig G Moreno-Martínez A Martínez JA Jiménez de Anta T Mensa J Vila J 《Journal of clinical microbiology》2002,40(12):4445-4449
Differences in the presence of nine urovirulence factors among clinical isolates of Escherichia coli causing cystitis and pyelonephritis in women and prostatitis in men have been studied. Hemolysin and necrotizing factor type 1 occur significantly more frequently among isolates causing prostatitis than among those causing cystitis (P < 0.0001) or pyelonephritis (P < 0.005). Moreover, the papGIII gene occurred more frequently in E. coli isolates associated with prostatitis (27%) than in those associated with pyelonephritis (9%) (P < 0.05). Genes encoding aerobactin and PapC occurred significantly less frequently in isolates causing cystitis than in those causing prostatitis (P < 0.01 and P < 0.0001, respectively) and pyelonephritis (P < 0.01 and P < 0.0001, respectively). No differences in the presence of Sat or type 1 fimbriae were found. Finally, AAFII and Bfp fimbriae are no longer considered uropathogenic virulence factors since they were not found in any of the strains analyzed. Overall, the results showed that clinical isolates producing prostatitis need greater virulence than isolates producing pyelonephritis in women or, in particular, cystitis in women (P < 0.05). Overall, the results suggest that clinical isolates producing prostatitis are more virulent that those producing pyelonephritis or cystitis in women. 相似文献
30.
Siddharth K. Prakash Soniely Lugo‐Ruiz Michelle Rivera‐Dávila Nunilo Rubio Jr. Avni N. Shah Rebecca C. Knickmeyer Cindy Scurlock Melissa Crenshaw Shanlee M. Davis Gary A. Lorigan Aaron T. Dorfman Karen Rubin Cheryl Maslen Vaneeta Bamba Paul Kruszka Michael Silberbach Scientific Advisory Board of the TSRR 《American journal of medical genetics. Part C, Seminars in medical genetics》2019,181(1):7-12
To address knowledge gaps about Turner syndrome (TS) associated disease mechanisms, the Turner Syndrome Society of the United States created the Turner Syndrome Research Registry (TSRR), a patient‐powered registry for girls and women with TS. More than 600 participants, parents or guardians completed a 33‐item foundational survey that included questions about demographics, medical conditions, psychological conditions, sexuality, hormonal therapy, patient and provider knowledge about TS, and patient satisfaction. The TSRR platform is engineered to allow individuals living with rare conditions and investigators to work side‐by‐side. The purpose of this article is to introduce the concept, architecture, and currently available content of the TSRR, in anticipation of inviting proposals to utilize registry resources. 相似文献