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91.
PURPOSE: We investigate the patterns of failure in the treatment of glioblastoma(GBM) based on clinical target volume(CTV) margin size,dose delivered to the site of initial failure,and the use of temozolomide and intensity-modulated radiotherapy(IMRT).METHODS: Between August 2000 and May 2010,161 patients with GBM were treated with radiotherapy with or without concurrent temozolomide.Patients were treated with CTV expansions that ranged from 5 to 20 mm using a shrinking field technique.Patterns of failure and time to progression and overall survival were compared based on CTV margin,use of temozolomide,and use of IMRT.Kaplan Meier analysis was used to estimate survival times,and χ test was used for comparison of cohorts.RESULTS: For patients treated with 5-,10-,and 15-to 20-mm CTV,79%,77%,and 86% experienced failures in the 60 Gy volume,respectively.Forty-eight percent,55%,and 66% of patients with 5-,10-,and 15-to 20-mm CTV experienced failures in the 46 Gy volume,respectively.There was no statistical difference between patients treated with 5-,10-,15-to 20-mm margins with regard to 60 Gy failure(P=0.76),46 Gy failure(P=0.51),or marginal failure(P=0.73).Eighty percent of patients receiving temozolomide experienced failures in the 60 Gy volume.There was no increased likelihood of marginal failures in patients receiving IMRT(P =0.97).CONCLUSIONS: Modern treatment techniques including use of concurrent temozolmide,limited CTV margin size,and IMRT have not greatly changed the patterns of failure of GBM.  相似文献   
92.
OBJECTIVES: An International Workshop addressed the prevalence and classification of HIV/AIDS associated oral lesions.
DESIGN: Five questions provided the framework for discussion and literature review. What is the prevalence of oral lesions in children and adults? Should the accepted classification of HIV-related oral lesions be modified in the light of recent findings? Why is there a gender difference in the prevalence of oral lesions in developed and developing countries? Are there unusual lesions present in developing countries? Is there any association between modes of transmission and the prevalence of oral lesions?
RESULTS: Workshop discussion emphasized the urgent need for assistance in the development of expertise to obtain accurate global prevalence data for HIV-associated oral lesions. Oral candidiasis has been consistently reported as the most prevalent HIV-associated oral lesion in all ages. Penicilliosis marneffei, a newly described fungal infection, has emerged in South-east Asia. Oral hairy leukoplakia and Kaposi's sarcoma appear to be associated with male gender and male-to-male HIV transmission risk behaviours. These lesions occur only rarely in children.
CONCLUSIONS: Additional prevalence data are needed from developing countries prior to substantially altering the 1993 ECC/WHO Classification of oral lesions associated with adult HIV infection. The workshop confirmed current oral disease diagnostic criteria.  相似文献   
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94.
目的比较5French(5F)及6French(6F)导引导管在经桡动脉冠状动脉介入治疗(TRI)患者中的安全性及有效性。方法共纳入2009年2月至2010年3月患者,收集相关资料录入数据库,包括患者基线临床资料、导引导管的尺寸、靶血管、靶病变的特点、手术的成功率、手术失败原因、经桡动脉冠状动脉介入治疗手术的成功率及失败原因、患者住院期间主要不良心血管事件率及术后桡动脉闭塞率。结果连续纳入患者共185例,接受195次经桡动脉冠状动脉介入治疗术,平均年龄(57±11)岁(33~81岁);其中54例患者纳入6F导引导管组,共进行56次手术,治疗89处病变;138例患者纳入5F导引导管组,共行146次手术,治疗231处病变。AHA B2/C型病变比例在两组间差异无统计学意义(5F组43.7%/29.0%比6F组46.1%/34.6%,P>0.05),但慢性闭塞性病变、分叉病变、钙化病变5F组显著少于6F组(5.6%比14.6%,P=0.005;23.4%比37.1%,P=0.012;9.5%比47.2%,P<0.001);组间的手术时间[(45±21)min比(46±19)min)]、手术X线曝光时间[(15±12)min比(16±13)min]、使用造影剂量[(140±45)ml比(156±56)ml]差异均无显著统计学意义(P>0.05),但是5F组造影剂用量有减少的趋势(P=0.066);组间住院时间[(1.40±1.26)d比(1.29±0.69)d]和手术成功率(95.2%比94.6%)也差异无统计学意义(P>0.05);5F组1例患者术后桡动脉闭塞,6F组无患者术后桡动脉闭塞(P=1.0),5F组1例发生卒中。结论经桡动脉冠状动脉介入治疗,即使是复杂及高危冠脉病变,5F导引导管有效、安全,手术成功率不低于常规使用的6F导引导管;换用5F导引导管进行冠状动脉介入治疗是一种有吸引力的选择。  相似文献   
95.
A prospective study of blood donations in healthy elderly persons   总被引:1,自引:0,他引:1  
Iron stores were observed in 57 healthy elderly volunteers, between 63 and 77 years of age, who donated 5 units of blood over approximately 1 year. An equal number of nondonors who contributed approximately 7 mL of blood at each visit for iron status measurements only were seen at the same frequency as the donor population. At entrance to the study, iron stores in women and men averaged 724 and 875 mg, respectively. After five donations, mean iron stores dropped to 67 mg in women (n = 27) and 362 mg in men (n = 30); four women (15%) became iron deficient, while two (7%) developed iron deficiency anemia. Three men (10%) developed iron deficiency, but none were found to be anemic. Mean intakes of iron were 23.3 and 22.5 mg per day, respectively, for women and men. Iron intakes were adequate to meet iron requirements of nondonors, but they were not sufficient to halt the steady decrease in iron stores among the donor population, in whom iron absorption increased from approximately 5 percent at entrance to 14 percent at the time of the fifth donation. In summary, healthy elderly persons may contribute to the national blood resource; however, donations should probably be limited to less than five per year or donors should regularly take an iron supplement to preserve reasonable amounts of iron reserves.  相似文献   
96.
97.
The effect of feeding hypolipidemic peroxisome proliferators on the induction of altered hepatic foci (AHF) in Fischer rats was studied in order to determine whether such agents can induce or promote the development of AHF. In the first study, rats were fed ciprofibrate (10 mg/kg/day) for 1 yr. AHF, neoplastic nodules, and hepatocellular carcinomas were induced. The presence of putative gamma-glutamyltranspeptidase (GGT) activity was numerically the most common marker, although it was absent in larger foci and nodules. A deficiency in canalicular ATPase and glucose-6-phosphatase provided the best markers for the larger foci and nodules. In the second study, rats were subjected to partial hepatectomy, and half of the animals were then intubated with diethylnitrosamine (10 mg/kg). One wk later, rats were fed Wy-14,643 at concentrations of 0, 0.05, and 0.1% in the diet for 6 mo. At 6 mo, the number and volume of foci were increased by the feeding of Wy-14,643 after partial hepatectomy alone and were greatly increased when Wy-14,643 was fed after partial hepatectomy/diethylnitrosamine administration. Canalicular adenosine triphosphatase and glucose-6-phosphatase deficiencies were the most common markers of AHF, and AHF of these phenotypes occupied practically all of the focal volume. The larger AHF did not express GGT, and those foci exhibiting GGT were much less common and occupied very little volume. The absence of the GGT protein itself, as opposed to an inhibition of GGT activity, was verified by immunohistochemical staining using an antibody to GGT. These studies show that hypolipidemic peroxisome proliferators can stimulate an increase in AHF following a single dose of diethylnitrosamine and a mitotic stimulus, and they thus can act as promoters in two-stage liver carcinogenesis. GGT is a poor marker for identifying AHF induced by peroxisome proliferators during the early, premalignant phase of hepatocarcinogenesis.  相似文献   
98.
Models of hepatocarcinogenesis in the rat--contrasts and comparisons   总被引:4,自引:0,他引:4  
A variety of approaches for the induction of altered hepatic foci, hyperplastic nodules, and hepatocellular carcinomas in rat liver have been developed. These protocols, aided by the appearance of preneoplastic lesions during the carcinogenic process, have proven to be very useful for examining many of the characteristics of events involved in rat hepatocarcinogenesis. A number of models have demonstrated distinct steps or stages in the progression of the carcinogenic process. These protocols are currently employed in the classification and distinction of agents effecting hepatocarcinogenesis at one or more of its stages. This review presents an overview of the present-day multistage hepatocarcinogenesis model systems in the rat, with contrasts and comparisons of these systems. The potential uses of the model systems in the identification of complete carcinogens, initiating agents, and promoting agents devoid of initiating action are discussed.  相似文献   
99.
Introduction:  Temporary GES (tempGES) can improve both gastric emptying and symptoms in post-surgical gastroparesis (PS-GP). (SSAT 2004). Long-term effects on GI symptoms and gastric emptying are unknown. Since many PS-GP patients have non-delayed emptying, the long-term effect on baseline normal or rapid emptying is also unknown.
Patients:  36 pts (6 M, 30 F, mean age 42 years) with post-surgical: Bilroth I ( n  = 11), Bilroth II ( n  = 4), other gastric surgery ( n  = 21) disordered gastric emptying were evaluated.
Methods:  GI symptoms (vomiting = V, Total = TSS), and solid meal gastric emptying (GET) at 1 and 4 h, were compared at baseline (Base), after temporary (tempGES) and permanent (permGES) gastric electrical stimulation as previously described (NGM, 2004; 16: 635.) Long-term follow-up for permanent GES ranged from 6 month to 10 years. Results were compared by t-tests, and are reported as means ± SEM.
Results:  29 of the 36 patients were able to tolerate food for baseline quantitative gastric emptying testing. 20 patients had delayed and 9 patients had non-delayed gastric emptying, with 7/9 being rapid. With both tempGES and permGES, GI symptoms improved (p < 0.05). Both tempGES and permGES showed accelerated GET for delayed patients and generally slowed GET for non-delayed (p < 0.05 for 1 h values). See tables below.
Conclusions:  In a large group of post-surgical GP patients, temporary and permanent gastrointestinal electrical stimulation improved GI symptoms independent of gastric emptying and for a prolonged time. GES improves symptoms independent of baseline gastric emptying, and improves GET dependent on the baseline gastric emptying.
 
  相似文献   
100.
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