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31.
Michael R Zalutsky David A Reardon Gamal Akabani R Edward Coleman Allan H Friedman Henry S Friedman Roger E McLendon Terence Z Wong Darell D Bigner 《Journal of nuclear medicine》2008,49(1):30-38
alpha-Particle-emitting radionuclides, such as (211)At, with a 7.2-h half-life, may be optimally suited for the molecularly targeted radiotherapy of strategically sensitive tumor sites, such as those in the central nervous system. Because of the much shorter range and more potent cytotoxicity of alpha-particles than of beta-particles, (211)At-labeled agents may be ideal for the eradication of tumor cells remaining after surgical debulking of malignant brain tumors. The main goal of this study was to investigate the feasibility and safety of this approach in patients with recurrent malignant brain tumors. METHODS: Chimeric antitenascin monoclonal antibody 81C6 (ch81C6) (10 mg) was labeled with 71-347 MBq of (211)At by use of N-succinimidyl 3-[(211)At]astatobenzoate. Eighteen patients were treated with (211)At-labeled ch81C6 ((211)At-ch81C6) administered into a surgically created resection cavity (SCRC) and then with salvage chemotherapy. Serial gamma-camera imaging and blood sampling over 24 h were performed. RESULTS: A total of 96.7% +/- 3.6% (mean +/- SD) of (211)At decays occurred in the SCRC, and the mean blood-pool percentage injected dose was < or = 0.3. No patient experienced dose-limiting toxicity, and the maximum tolerated dose was not identified. Six patients experienced grade 2 neurotoxicity within 6 wk of (211)At-ch81C6 administration; this neurotoxicity resolved fully in all but 1 patient. No toxicities of grade 3 or higher were attributable to the treatment. No patient required repeat surgery for radionecrosis. The median survival times for all patients, those with glioblastoma multiforme, and those with anaplastic astrocytoma or oligodendroglioma were 54, 52, and 116 wk, respectively. CONCLUSION: This study provides proof of concept for regional targeted radiotherapy with (211)At-labeled molecules in oncology. Specifically, the regional administration of (211)At-ch81C6 is feasible, safe, and associated with a promising antitumor benefit in patients with malignant central nervous system tumors. 相似文献
32.
Thomas Schoeller Gottfried Wechselberger Judith Roger Heribert Hussl Georg M Huemer 《Journal of plastic, reconstructive & aesthetic surgery》2007,60(5):524-528
The deep inferior epigastric perforator (DIEP)-flap continues to be the standard treatment in microsurgical breast reconstruction. Reasons for the popularity of the DIEP-flap include the availability of a large amount of tissue for the reconstruction of large breasts, a reliable vascular anatomy and an aesthetically pleasing donor site scar. However, the DIEP-flap is not considered the optimal choice as the donor tissue in all patients. Previous abdominal surgeries with resulting scars may threaten the success of a free DIEP-flap due to compromised vascularity within the flap. We elaborated a technique to increase the safety of breast reconstruction with the DIEP-flap in the presence of an infraumbilical vertical scar. After raising the DIEP-flap in a traditional manner on one side with harvesting of a considerate length of the inferior epigastric vessels, a segment of the superior epigastric vessels is left attached to the main pedicle. This stump of the superior epigastric vessels is now anastomosed under the microscope to a paraumbilical perforator on the contralateral side of the flap for in-flap microvascular augmentation. The above-mentioned technique was applied in five patients who presented with an infraumbilical vertical scar and were reconstructed with a DIEP-flap because of breast cancer. In three of the five patients there was an additional risk factor present such as smoking or diabetes mellitus. In all five patients no major complication due to marginal perfusion of the contralateral side of the flap was encountered. In two patients there was minor breakdown of fatty tissue that was managed conservatively in both cases. In-flap microvascular augmentation of DIEP-flaps is a valuable tool for the plastic surgeon in microvascular breast reconstruction. It permits usage of the lower abdominal tissue even if perfusion is compromised due to midline scarring. We recommend this technique as a safe alternative in patients seeking autologous breast reconstruction in the presence of a midline abdominal scar. 相似文献
33.
Michelle K Nurzenski N Kathryn Briffa Roger I Price Benjamin C C Khoo Amanda Devine Thomas J Beck Richard L Prince 《Journal of bone and mineral research》2007,22(3):416-424
A population-based study on 1008 postmenopausal women identified that the 24% of women achieving high levels of PA and CI had 3.4-4.4% higher femoral bone strength in axial compression and 1.7-5.2% in bending than those achieving low levels, indicating that lifestyle factors influence bone strength in the proximal femur. INTRODUCTION: Extensive research has shown that increased physical activity (PA) and calcium intake (CI) decrease the rate of bone loss; however, there is little research on how these lifestyle variables affect bone geometry. This study was designed to investigate the effects of modifiable lifestyle variables, habitual PA and dietary CI, on femoral geometry in older women. MATERIALS AND METHODS: Femoral geometry, habitual PA, and dietary CI were measured in a population-based sample of 1008 women (median age+/-interquartile range, 75+/-4years) enrolled in a randomized controlled trial (RCT) of calcium supplementation. Baseline PA and CI were assessed by validated questionnaires, and 1-year DXA scans (Hologic 4500A) were analyzed using the hip structural analysis technique. Section modulus (Z), an index of bending strength, cross-sectional area (CSA), an index of axial compression strength, subperiosteal width (SPW), and centroid position, the position of the center of mass, were measured at the femoral neck (NN), intertrochanter (IT), and femoral shaft (FS) sites. These data were divided into tertiles of PA and CI, and the results were compared using analysis of covariance (ANCOVA), with corrections for age, height, weight, and treatment (calcium/placebo). RESULTS AND CONCLUSIONS: PA showed a significant dose-response effect on CSA all hip sites (p<0.03) and Z at the narrow neck and intertrochanter sites (p<0.02). For CI, there was a dose-response effect for centroid position at the intertrochanter (p=0.03). These effects were additive, such that the women (n=240) with PA in excess of 65.5 kcal/day and CI in excess of 1039 mg/day had significantly greater CSA (NN, 4.4%; IT, 4.3%; FS, 3.4%) and Z (NN, 3.9%; IT, 5.2%). These data show a favorable association between PA and aspects of bone structural geometry consistent with better bone strength. Association between CI and bone structure was only evident in 1 of 15 variables tested. However, there was evidence that there may be additive effects, whereby women with high levels of PA and CI in excess of 1039 mg/day had significantly greater CSA (NN, 0.4%; FS, 2.1%) and Z (IT, 3.0%) than women with high PA but low CI. These data show that current public health guidelines for PA and dietary CI are not inappropriate where bone structure is the health component of interest. 相似文献
34.
35.
Christophe Doddoli Adrian Aragon Fabrice Barlesi Bruno Chetaille Stéphane Robitail Roger Giudicelli Pierre Fuentes Pascal Thomas 《European journal of cardio-thoracic surgery》2005,27(4):680-685
OBJECTIVE: To assess the therapeutic effect of the extent of lymph node dissection performed in patients with a stage pI non-small-cell lung cancer (NSCLC). METHODS: We analysed data on 465 patients with stage I NSCLC who were treated with surgical resection and some form of lymph node sampling. The median number of lymph node sampled was 10 and the median number of ipsilateral mediastinal lymph node stations sampled was two. We chose to define a procedure that harvested 10 or more lymph nodes and sampled two or more ipsilateral mediastinal stations as a lymphadenectomy, by contrast with sampling when one or both criteria were not satisfied. The effect of the surgical techniques: lymph node sampling (LS; n=207) vs. lymphadenectomy (LA; n=258) on 30-day mortality and overall survival were investigated. RESULTS: A total of 6244 lymph nodes was examined, including 4306 mediastinal lymph nodes. The mean (+/-SD) numbers of removed lymph nodes were 7+/-6.1 per patient following LS vs.18.6+/-9.3 following LA (P=0.001). An average mean of 1+/-0.90 mediastinal lymph node station per patient was sampled following LS vs. 2.7+/-0.8 following LA (P<10(-6)). Overall 30-day mortality rates were 2.4 and 3.1%, respectively. LA was disclosed as a favourable prognosticator at multivariate analysis (Hazard Risk: 1.43; 95% Confidence Interval: 1.00-2.04; P=0.048), together with younger patient age, absence of blood vessels invasion, and smaller tumour size. CONCLUSIONS: Importance of lymph node dissection affects patients outcome, while it does not enhance the operative mortality. A minimum of 10 lymph nodes assessed, and two mediastinal stations sampled are suggested as possible pragmatic markers of the quality of lymphadenectomy. 相似文献
36.
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38.
E Roberto Orellana Joseph F Picciano Roger A Roffman Fred Swanson Seth C Kalichman 《AIDS education and prevention》2006,18(4):348-361
Providing HIV prevention services to high-risk individuals remains challenging. We assessed factors associated with nonparticipation among high-risk, sexually active MSM found eligible to participate in a brief, telephone-delivered HIV prevention trial designed to evaluate the efficacy of motivational enhancement therapy (the Sex Check). Two levels of nonparticipation are evaluated: eligible participants who did versus those who did not complete their baseline/enrollment interview, and enrolled participants who did versus those who did not attend any of their counseling sessions. Nonenrollers were younger, less educated, more closeted, and were more likely to report sex with an injection drug using partner. Enrolled participants who did not engage in their counseling session(s) were less educated, reported greater use of alcohol and drugs during sex and use of injection drugs. Innovative methods to reduce barriers to engaging high-risk, sexually active MSM in risk reduction counseling are needed. 相似文献
39.
Suryanarayanan Nagasubramanian Robert H. Stewart Roger A. Hitchings 《International ophthalmology》1994,18(1):5-8
Corneal thickness measurements and endothelial cell counts were carried out in 34 patients undergoing treatment for glaucoma with 4% pilocarpine gel between 18 to 78 months after initiation of therapy. The corneal thickness and endothelial cell population were found to be within normal limits in all cases except two, one patient with increased corneal thickness who had recently undergone cataract and glaucoma filtering surgery and another patient with decreased cell count who had an old endothelial scar sustained prior to pilocarpine gel therapy. There was a very close correlation for both of these parameters noticed in patients treated with pilocarpine gel and in age-matched control group of patients with glaucoma. The present study has shown that there are no adverse corneal effects with pilocarpine gel therapy. 相似文献
40.
Objective. To provide national estimates of the effect of out-of-pocket premiums and benefits on Medicare beneficiaries' choice among managed care health plans.
Data Sources/Study Setting. The data represent the population of all Medicare+Choice (M+C) plans offered to Medicare beneficiaries in the United States in 1999.
Study Design. The dependent variable is the log of the ratio of the market share of the j th health plan to the lowest cost plan in the beneficiary's county of residence. The explanatory variables are measures of premiums and benefits in the j th health plan relative to the premiums and benefits in the lowest cost plan.
Data Collection Methods. The data are from the 1999 Medicare Compare database, and M+C enrollment data from the Centers for Medicare and Medicaid Services (CMS).
Principal Findings. A $10 increase in an M+C plan's out-of-pocket premium, relative to its competitors, is associated with a decrease of four percentage points in the j th plan's market share (i.e., from 25 to 21 percent), holding the premiums of competing plans constant.
Conclusions. Although our price elasticity estimates are low, the market share losses associated with small changes in a health plan's premium, relative to its competitors, may be sufficient to discipline premiums in a competitive market. Bidding behavior by plans in the Medicare Competitive Pricing Demonstration supports this conclusion. 相似文献
Data Sources/Study Setting. The data represent the population of all Medicare+Choice (M+C) plans offered to Medicare beneficiaries in the United States in 1999.
Study Design. The dependent variable is the log of the ratio of the market share of the j th health plan to the lowest cost plan in the beneficiary's county of residence. The explanatory variables are measures of premiums and benefits in the j th health plan relative to the premiums and benefits in the lowest cost plan.
Data Collection Methods. The data are from the 1999 Medicare Compare database, and M+C enrollment data from the Centers for Medicare and Medicaid Services (CMS).
Principal Findings. A $10 increase in an M+C plan's out-of-pocket premium, relative to its competitors, is associated with a decrease of four percentage points in the j th plan's market share (i.e., from 25 to 21 percent), holding the premiums of competing plans constant.
Conclusions. Although our price elasticity estimates are low, the market share losses associated with small changes in a health plan's premium, relative to its competitors, may be sufficient to discipline premiums in a competitive market. Bidding behavior by plans in the Medicare Competitive Pricing Demonstration supports this conclusion. 相似文献