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41.
Deborah P Waber Lewis B Silverman Lori Catania William Mautz Montse Rue Richard D Gelber Donna E Levy Meredith A Goldwasser Heather Adams Annie Dufresne Victoria Metzger Ivonne Romero Nancy J Tarbell Virginia Kimball Dalton Stephen E Sallan 《Journal of clinical oncology》2004,22(13):2701-2707
PURPOSE: We evaluated 8-year survival and late neuropsychologic toxicity in children with acute lymphoblastic leukemia treated in a randomized clinical trial to test whether hyperfractionated (twice daily) cranial radiation therapy (CRT) can reduce incidence and severity of late toxicities associated with 18 Gy of CRT. PATIENTS AND METHODS: Between 1987 and 1995, 369 children treated on two consecutive Dana-Farber Cancer Institute Consortium protocols for high-risk acute lymphoblastic leukemia were randomly assigned to conventionally fractionated CRT (CFX) or hyperfractionated CRT (HFX) to a total dose of 18 Gy. Neuropsychologic testing was completed for 125 of 287 children in continuous complete remission. Event-free and overall survival, as well as neuropsychologic function, were compared for the two arms of the protocol. RESULTS: Eight-year event-free survival (+/- SE) was 80% +/- 3% for children randomly assigned to CFX and 72% +/- 3% for HFX (P =.06). Overall survival was 85% +/- 3% for CFX and 78% +/- 3% for HFX (P =.06). CNS relapses occurred in 2.8% of patients receiving CFX and 2.7% receiving HFX (P =.99). Cognitive function for both groups was solidly in the average range, with no group differences in intelligence, academic achievement, visuospatial reasoning, or verbal learning. Children on the HFX arm exhibited a modest advantage for visual memory (P <.05). CONCLUSION: HFX provides no benefit in terms of cognitive late effects and may compromise antileukemic efficacy. HFX should not be substituted for conventionally dosed CRT in children who require radiation therapy for treatment of acute lymphoblastic leukemia. 相似文献
42.
德国人口不到9000万,政府对医疗卫生管理实行分层次操作(见表1)。德国的医生分为住院医疗医生和诊所医生。联邦医生联合会负责医生的管理工作,该机构主要负责医生的继续医学教育、职称晋升、医疗纠纷的调解等。保险医生联合会则负责支付医生的各种费用。 相似文献
43.
“10年内,世界上最大的国际性医疗集团将产生在中国!”新加坡百汇康护集团私人有限公司副总裁佘伟彦如此预言。 相似文献
44.
Elaine A Merrill Rebecca A Clewell Peter J Robinson Annie M Jarabek Jeffery M Gearhart Teresa R Sterner Jeffrey W Fisher 《Toxicological sciences》2005,83(1):25-43
Detection of perchlorate (ClO4-) in several drinking water sources across the U.S. has lead to public concern over health effects from chronic low-level exposures. Perchlorate inhibits thyroid iodide (I-) uptake at the sodium (Na+)-iodide (I-) symporter (NIS), thereby disrupting the initial stage of thyroid hormone synthesis. A physiologically based pharmacokinetic (PBPK) model was developed to describe the kinetics and distribution of both radioactive I- and cold ClO4- in healthy adult humans and simulates the subsequent inhibition of thyroid uptake of radioactive I- by ClO4-. The model successfully predicts the measured levels of serum and urinary ClO4- from drinking water exposures, ranging from 0.007 to 12 mg ClO4-/kg/day, as well as the subsequent inhibition of thyroid 131I- uptake. Thyroid iodine, as well as total, free, and protein-bound radioactive I- in serum from various tracer studies, are also successfully simulated. This model's parameters, in conjunction with corresponding model parameters established for the male, gestational, and lactating rat, can be used to estimate parameters in a pregnant or lactating human, that have not been or cannot be easily measured to extrapolate dose metrics and correlate observed effects in perchlorate toxicity studies to other human life stages. For example, by applying the adult male rat:adult human ratios of model parameters to those parameters established for the gestational and lactating rat, we can derive a reasonable estimate of corresponding parameters for a gestating or lactating human female. Although thyroid hormones and their regulatory feedback are not incorporated in the model structure, the model's successful prediction of free and bound radioactive I- and perchlorate's interaction with free radioactive I- provide a basis for extending the structure to address the complex hypothalamic-pituitary-thyroid feedback system. In this paper, bound radioactive I- refers to I- incorporated into thyroid hormones or iodinated proteins, which may or may not be bound to plasma proteins. 相似文献
45.
46.
Oxidative stress is the root cause of diabetic macro- and microvascular complications. Biochemical and epidemiological studies indicate that current treatments for diabetes do not reduce risks of developing complications, suggesting their inability to alleviate the levels of oxidative stress. This study in streptozotocin (STZ)-induced diabetic rats was carried out to investigate the effect of combining the antidiabetic drug, metformin, with an ethanolic extract of Scutellaria baicalensis, a plant whose root is known for its radical scavenging activity. Three groups of STZ-induced diabetic rats were given the following treatments for 30 days: (1) metformin 500 mg/kg, (2) S. baicalensis 400 mg/kg, (3) metformin 500 mg/kg + S. baicalensis extract 400 mg/kg. In addition, vehicle-treated diabetic and nondiabetic controls were used in the experiment. The rats treated with S. baicalensis and metformin + S. baicalensis had elevated hepatic activities of the antioxidant enzymes--superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) compared to the vehicle- and metformin-treated diabetic groups (p < 0.05). Plasma and hepatic lipid peroxide concentrations in the herb-treated and herb + metformin-treated groups were also significantly reduced (p < 0.05). In addition, the combined treatment caused significant elevations of plasma and pancreatic insulin levels and reductions of plasma and hepatic triglycerides (TG) and cholesterol levels. The study thus showed that S. baicalensis enhanced the antidiabetic effect of metformin in STZ-induced diabetic rats by improving the antioxidant status. It also increased pancreatic insulin content as well as improved the lipid profile in these rats. 相似文献
47.
Since 1994 the Institute of Forensic Medicine, Aarhus University, has performed colposcopic examinations of children suspected of sexual abuse or assault. The institute serves an area with approximately 2.5 million inhabitants and performs 50-75 colposcopic examinations per year. When indicated the children are tested for Chlamydia trachomatis. Vaginal samples are observed for growth in culture and DNA-amplification tests are performed. So far we have found only one positive culture. This was a now 11-yr-old girl who allegedly was assaulted once at the age of eight. The colposcopic examination showed normal ano-genital findings. The fact that the girl had tested positive for Chlamydia trachomatis is a strong indicator of abuse, and in the case of normal ano-genital findings, serves as an important evidence factor in court. In the future it may be possible to trace the infection to the alleged perpetrator by specific sub typing of Chlamydia Trachomatis. 相似文献
48.
Véronique Bissonnette-Maheux Audrée-Anne Dumas Véronique Provencher Annie Lapointe Marilyn Dugrenier Sharon Straus Marie-Pierre Gagnon Sophie Desroches 《Journal of the Academy of Nutrition and Dietetics》2018,118(7):1220-1227.e3
Background
Healthy eating blogs are knowledge translation tools used by nutrition and dietetics practitioners for helping people improve their health behaviors and food choices.Objective
Our aim was to explore women’s perceptions of the usefulness and ease of use of healthy eating blog (HEB) characteristics that might increase potential users’ intention to use them as tools to improve their dietary habits.Design
We conducted qualitative research using semi-structured individual interviews.Participants
Thirty-three women (mean age of 44 years; range=27 to 61 years) living in the Quebec City, Canada, metropolitan area were studied.Intervention
Four existing HEBs, written by French-Canadian registered dietitians (RDs) whose main objective was the promotion of a healthy diet, were explored by women during individual interviews. A standardized open-ended interview questionnaire based on the Technology Acceptance Model was used to identify women's perceptions about characteristics of type of blog content delivery, RD blogger's delivery of information, blog layout, and blog design.Main outcome measures
Women's perceptions toward the contribution of HEB characteristics to the usefulness and ease of use of those tools to improve their dietary habits were measured.Analyses performed
Interviews were audiorecorded, transcribed verbatim, coded, and analyzed through an inductive content analysis using NVivo software.Results
The most useful characteristics of type of blog content delivery identified by women were recipes, hyperlinks, and references. Among characteristics of RD blogger's delivery of information, most women reported that interaction between blog readers and the RD blogger created a sense of proximity and of connection that was helpful for improving their dietary behaviors. Women's perceptions toward various characteristics of blog layout and design were also discussed.Conclusions
Incorporating specific characteristics when designing HEBs should be considered by RDs and future research to promote the use of those tools to support dietary behavior change efforts of internet users. 相似文献49.
50.
BACKGROUND: Total thyroidectomy is increasingly being adopted for patients requiring surgical treatment for Graves' disease based on a comparable surgical risk and the lack of recurrence, as well as the questionable ability of subtotal thyroidectomy to maintain euthyroidism. The purpose of the present paper was to evaluate its safety and efficiency. METHODS: Total thyroidectomy was adopted as part of the routine surgical treatment for Graves' disease from 2000. Patients who underwent subtotal thyroidectomy (STT) from 1995 to 1999 (n = 119) were compared with those who underwent total thyroidectomy (TT) from 2000 to 2003 (n = 98) with respect to immediate postoperative morbidity and long-term outcome. RESULTS: Fourteen (11.8%) and 22 patients (22.4%) required calcium supplement on discharge in the STT and TT groups, respectively (P < 0.05). One (0.8%) and three patients (3.1%) developed permanent hypocalcaemia, respectively. Transient recurrent laryngeal nerve palsy occurred in 9.2% (n = 11) and 5.1% (n = 5) of patients or 5.0% and 2.6% of nerves at risk after STT and TT, respectively. None of the patients had permanent nerve palsy. The estimated blood loss was less and hospital stay shorter after TT. During a mean follow up of 64 months, 86 patients (72.3%) in the STT group required thyroxine replacement and seven patients (5.9%) developed relapse. CONCLUSION: Subtotal thyroidectomy was associated with relapse as well as hypothyroidism in a significant proportion of patients during long-term follow up. Total thyroidectomy can be performed as safely as STT and should be recommended as the procedure of choice for patients requiring surgical treatment for Graves' disease. 相似文献