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991.
Stereotactic radiosurgery (SRS) is commonly used to treat brain metastases, particularly in the oligometastatic setting. This study analyses our initial experience in treating oligometastatic brain disease using Volumetric Modulated Arc Therapy (VMAT) to deliver hypofractionated stereotactic radiotherapy (HFSRT). Sixty-one patients were treated with HFSRT with a median dose of 24 Gy (range 22–40 Gy) in a median of three fractions (range 2–10 fractions). With a median follow-up of 23 months, the local control rate was 74 % for the entire cohort. Local control was 87 % for patients who had surgery with no radiological evidence of residual disease followed by HFSRT compared with 69 % in patients treated with HFSRT alone. The overall median time post radiotherapy to local failure was 8.6 months and to extracranial failure was 7.9 months. The mean time to distant brain failure was 9.9 months. Twenty-two patients (36 %) died during the study with median time to death of 4.4 months. Median overall survival (OS) from treatment was 21 months and 12 month OS was 60 %. Our experience with HFSRT using VMAT for oligometastatic brain metastases in the post-operative setting demonstrates comparable local control and survival rates compared with international published data. In the intact brain metastasis setting, local control using the dose levels and delivery in this cohort may be inferior to radio-surgical series. Local control is independent of histology. Careful selection of patients remains critical.  相似文献   
992.

Background  

To describe and compare visual function measures of two groups of school age children (6-14 years of age) attending a specialist eyecare practice in Austria; one group referred to the practice from educational assessment centres diagnosed with reading and writing difficulties and the other, a clinical age-matched control group.  相似文献   
993.
994.

Purpose

Craniopharyngioma is a common pediatric brain tumor, with a high rate of recurrence after primary treatment. This retrospective study investigated the effect of various primary treatments on surgical strategies and outcomes for recurrent craniopharyngiomas.

Methods

The study population comprised 35 children (mean age 8.77 years, range 1–16 years) with recurrent craniopharyngioma re-operated from January 1990 to January 2009. The recurrent craniopharyngiomas were excised whenever possible. For analysis, the patients were divided into four groups according to the primary treatment: radical tumor resection (A), incomplete tumor resection (B), radiotherapy + incomplete tumor resection (C), and Ommaya reservoir placement + incomplete tumor resection (D).

Results

Group B had a significantly shorter recurrence-free interval than groups A, C, or D. Outcomes were significantly different among the four groups. The hypothalamic status scores of groups A (2.38 ± 0.27) and C (2.28 ± 0.42) were significantly higher than that of group B (1.64 ± 0.20). There were no statistical differences between any two other groups.

Conclusions

In children, the primary treatments for craniopharyngioma should be considered when choosing the surgical strategy for recurrence. Radiotherapy before repeated surgery can result in a worse functional outcome and hypothalamic-pituitary function.
  相似文献   
995.
Purpose All-trans retinoic acid (ATRA) polymeric micelles were developed for parenteral administration. The distribution characteristics and antitumor activities of ATRA polymeric micelles were evaluated after intravenous administration to mice bearing CT26 solid tumors. Methods ATRA incorporated in poly(ethylene glycol)-poly(benzyl aspartate) block copolymer was prepared by the evaporation method. The levels of [3H]ATRA in blood and tissue including tumor were determined by measuring the radioactivity after injection into mice. The tumor volume and the survival of the mice were determined to assess the anticancer activity. Results The delivery of ATRA by polymeric micelles prolonged the blood circulation and enhanced the accumulation of ATRA in the tumor tissue compared with the administration of free ATRA. Tumor growth was significantly delayed and the survival time of mice was prolonged following the treatment by ATRA polymeric micelles demonstrating the improved anticancer activity of ATRA. Conclusion Polymeric micelles are a promising and effective carrier of ATRA in order to enhance tumor delivery and they have a promising potential application in the treatment of solid tumors.  相似文献   
996.
Hypertension and dementia   总被引:2,自引:0,他引:2  
Hypertension is one of the principal risk factors for cerebrovascular diseases. Several epidemiologic studies have also indicated a positive correlation between cognitive decline or dementia and blood pressure level. Indeed, the results of most longitudinal studies show that cognitive functioning is often inversely proportional to blood pressure values measured 15 or 20 years previously. Cerebral infarcts, lacunae, and white matter changes are implicated in the pathogenesis of vascular dementia, but may also favor the development of Alzheimer’s disease. Microcirculation disorders and endothelial dysfunctions are also advanced to explain the deterioration in cognitive functions in hypertensive subjects. Data from recent therapeutic trials open the way to the prevention of dementia (vascular or Alzheimer’s type) by antihypertensive treatments and must be confirmed by other studies.  相似文献   
997.
Lee MW  Lee JM  Lee JY  Kim SH  Park EA  Han JK  Choi JY  Kim YJ  Suh KS  Choi BI 《European radiology》2007,17(4):1074-1080
The purpose of this study was to determine whether MR angiography utilizing the time resolved echo-shared angiographic technique (TREAT) can provide an effective assessment of the hepatic artery (HA) and portal vein (PV) in living donor candidates. MR angiography (MRA)was performed in 27 patients (23 men and 4 women; mean age, 31 years) by using TREAT. Two blinded radiologists evaluated HA anatomy, origin of segment IV feeding artery and PV anatomy in consensus. Qualitative evaluations of MRA images were performed using the following criteria: (a) overall image quality, (b) presence of artifacts, and (c) degree of venous contamination of the arterial phase. Using intraoperative findings as a standard of reference, the accuracy for the HA anatomy, origin of segment IV feeding artery and PV anatomy on TREAT-MRA were 93% (25/27), 85% (23/27), and 96% (26/27), respectively. Overall image qualities were as follows: excellent (n=22, 81%), good (n=4, 15%), and fair (n=1, 4%). Significant artifacts or venous contamination of the arterial phase images was not noted in any patient. TREAT-MRA can provide a complete evaluation of HA and PV anatomy during preoperative evaluation of living liver donors. Furthermore, it provides a more detailed anatomy of the HA without venous contamination.  相似文献   
998.
Pediatric migraine is a disabling condition, which can cause a significant impact on quality of life. Currently, no drugs have been approved by the FDA for its preventive treatment. Our aim was to review the medical literature concerning the efficacy and tolerability of topiramate in the prophylactic treatment of migraine in children and adolescents. A total of five papers were reviewed: two randomized controlled trials (RCTs), a post-hoc subset analysis of adolescents who had been included in three RCTs carried out on adults and two open studies. Topiramate has been proven to reduce headache frequency and the accompanying disability. The frequency of side effects varied considerably among studies, the most frequent being weight loss, anorexia, abdominal pain, difficulties in concentrating, sedation and paresthesia. Since these adverse events, although often transitory, may be distressing for the child, we strongly recommend to assess the disability caused by the migraine episodes before deciding to initiate a prophylactic treatment. Nevertheless, dropout rates due to side effects in the studies were very low.  相似文献   
999.
Since the early 1990s, laparoscopic techniques have been applied to a growing number of pancreatic surgeries. Laparoscopic pancreatic resections have been performed in patients with a variety of diseases including chronic pancreatitis, pancreatic trauma, congenital hyperinsulinism, and neoplasms of the pancreas; e.g., insulinoma, mucinous cystic neoplasm, intraductal papillary mucinous neoplasm, etc. Laparoscopic pancreatic resections with an en bloc lymph node dissection have also been performed for invasive carcinomas. The long-term results after laparoscopic resections for invasive pancreatic cancer, however, are still not well defined. Laparoscopic distal pancreatectomies with or without spleen preservation may benefit patients with reduced postoperative pain, shorter hospital stay, a quicker recovery to normal activity, and better cosmetic appearances based on retrospective analyses of collective series and case reports. Prospective randomized controlled trials are needed to validate these benefits. In contrast, laparoscopic proximal pancreatectomies with or without duodenum preservation remain controversial. Although a laparoscopic pancreaticoduodenectomy and laparoscopic duodenum-preserving pancreatic head resection are technically feasible, laparoscopic reconstruction after proximal pancreatectomies is not yet generally practicable but limited to personal experiences by highly skilled endoscopic surgeons. To justify the performance of laparoscopic proximal pancreatectomies, it is mandatory to demonstrate the potential clinical benefits and safety of these complicated procedures.  相似文献   
1000.
The authors examined the influence of cochlear implants on joint attention and social competence in severe to profoundly congenitally deaf toddlers. Twenty-seven hearing mothers and hearing toddlers (HH dyads), and 26 hearing mothers and deaf toddlers, 9 with cochlear implantation (HD-cochlear dyads), and 17 with no cochlear implantation (HD-no cochlear dyads) were observed engaging in joint attention. Mothers provided ratings of children’s social competence. HH and HD-cochlear dyads displayed more joint attention than HD-no cochlear dyads. Children who were in dyads who engaged in more joint attention were rated by their mothers as higher on expressive and compliance behaviors and lower on disruptive behaviors compared to children who were in dyads who engaged in lower levels of joint attention. Findings suggest that cochlear implants may aid in the early socio-emotional development of some deaf children.  相似文献   
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