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51.
One hundred and twenty eight Brazilian children with lymphoblastic leukaemia were intensively treated with a Berlin-Frankfurt-Munich based protocol. More children had a white cell count above 50 x 10(9)/l (31%) then observed in developed countries. After a median follow up of 31 months (11-58 months), the estimated probability of relapse free survival was 41% (7%) for the whole group. After adjustment in the Cox's multivariate model, malnutrition was the most significant adverse factor affecting duration of complete remission. Age above 8 years and high peripheral white cell count were also significant adverse factors. Among the nutritional indices, the height for age and weight for age z scores were both significant, whether the cut off points of z-2 or z = -1.28 were chosen to define malnutrition. A strong statistical association between the two indices was found; the contribution of height for age z score to the prediction of relapse free survival was more significant. Children with height for age z score < -2 had a relapse risk of 8.2 (95% confidence interval 3.1 to 21.9) relative to children with z score > -2. The results of this study suggest that socioeconomic and nutritional factors should be considered in the prognostic evaluation of children with leukaemia in developing countries.  相似文献   
52.
HPLC测定益肤霜中红霉素和地塞米松的含量   总被引:5,自引:0,他引:5  
采用HPLC测定益肤霜中红霉素和地塞米松的含量,控制制剂的质量。色谱条件:固定相为Kromasil C18柱;流动相为乙腈-0.2mol/L醋酸铵-水,流速0.8ml/min;检测波长215nm。以c对峰面积A作直线回归,红霉素在1.5-24g/L地塞米松在20-300mg/L的范围内,其浓度与峰面积呈直线关系。红霉素回收率为99.69%;地塞米松的回收率为100.28%。本法操作简便,结果准确,  相似文献   
53.
54.
Hemodynamic effects of isoproterenol, dopamine, and epinephrine were studied before and after acute beta-adrenergic blockade in 16 open-chest, anesthetized mongrel dogs. Beta blockade was induced with 1 mg. per kilogram of intravenous propranolol. Cardiac output measurements were obtained by thermal dilution, and pressure recordings were obtained in the right ventricle, pulmonary artery, left atrium, left ventricle, and aorta. Derived parameters included stroke volume, pulmonary and systemic vascular resistances, and peak left ventricular dP/dt. In the presence of propranolol, epinephrine became a lethal drug in large doses and did not increase cardiac output in standard doses. Dopamine, in 25 to 50 mcg. per kilogram per minute doses, increased arterial pressure and systemic resistance; cardiac output was diminished compared with dopamine, 10 mcg. per kilogram per minute, prior to propranolol, as a result of increased resistance and decreased LV contractility. Isoproterenol, 0.6 to 0.9 mcg. per kilogram per minute, 15 to 20 times standard dosages, had moderately positive inotropic effects and increased cardiac output. Left ventricular systolic pressure with isoproterenol after propranolol was reduced when compared with effects of smaller doses prior to propranolol. These observations suggest that none of the catecholamines studied would be optimal for circulatory support in heart failure in the presence of propranolol. The present results define a pharmacologic basis for design of appropriate drug combinations for circulatory support in beta-blocked animals.  相似文献   
55.

Background  

The purpose of this study was to evaluate the long-term results of partial liver resection for benign liver lesions.  相似文献   
56.
No absorbable cyanoacrylate tissue adhesive for safe internal surgical use is available. This prospective multicenter preliminary study was designed to evaluate the safety and effectiveness of an investigational absorbable cyanoacrylate (IAC) as an adjunct to hemostasis in arteriovenous shunt (AVS) procedures for dialysis access. Consenting adults (10) underwent placement of expanded polytetrafluoroethylene (ePTFE) upper extremity vascular grafts for AVS access using continuous 5-0 or 6-0 polypropylene after heparinization (> or =3000 units i.v.). Arterial anastomoses were evaluated after sealing with IAC followed by 120 seconds of polymerization time. After vascular clamp removal, the mean time to hemostasis was 9.1 +/- 28.8 seconds. Additionally, 90 per cent (9/10) and 100 per cent (10/10) achieved hemostasis by 1 and 5 minutes, respectively. No patients required further adjunctive hemostatic measures. Adverse event safety data analysis through 12 weeks revealed occlusion of graft or vessel in four patients and graft thrombosis in one patient, all thought unrelated to sealant use. Other unrelated adverse events (bleeding, death, deep venous thrombosis, edema, erythema, hematoma, infection, and rash) occurred in single patients. Thus, IAC could be a useful sealant for vascular procedures with a potentially satisfactory safety profile. Larger, randomized, multicenter, prospective trials to further evaluate the use of this material are indicated and appropriate.  相似文献   
57.

Background  

This article discusses the design of a study on the prevalence of health problems (both physical and mental) and the utilisation of health care services among asylum seekers and refugees in the Netherlands, including factors that may be related to their health and their utilisation of these services.  相似文献   
58.
59.
杜晓川  贾红梅  莫显斌 《医学争鸣》1999,20(9):S046-S046
1 病例报告 男,7岁.因双下肢不等长,右膝及右踝关节骨性肿大就诊.无明显外伤史,亦无红、肿、热、痛病史.查体:发育正常,营养良好.双下肢不等长,左60cm,右64cm,有跛行.右膝及右踝内侧肿大,肤色正常,关节活动无异常.X线:右侧半身诸关节(肩、肘、腕、髋、膝、踝)骨骺及干骺发育均较左侧增大,肢体较长,骨骺出现亦较对侧提早.如右尺骨茎突骨骺较左侧提早出现(图1).右肘关节肱骨小头骨骺较左侧增大(图2).右髋臼发育浅平,边缘毛糙,右股骨头骨骺较左侧明显增大,其距泪滴之距离较左侧大1.0cm,呈…  相似文献   
60.
目的:分析跟骨定量超声骨质测量中各参数与骨密度及形态计量学指标的相关性。方法:选择2004-01/2005-12广州市第六人民医院和中山大学三院骨科小腿以上截肢患者38例,将其跟骨定量超声测定的超声振幅衰减平均值与健康青年人骨峰值进行比较,>-2.5 SD者为骨量正常组(12例),<-2.5 SD者为骨质疏松组(26例)。分别进行跟骨定量超声、双能X线骨密度测量仪及骨形态计量学测量,应用直线相关分析法分析跟骨定量超声测定中各参数与骨密度及骨组织形态计量学各指标的相关性。结果:38例全部进入结果分析。①骨质疏松组跟骨超声振幅衰减平均值和骨硬度指数值均小于骨量正常组(P<0.01)。②骨量正常组跟骨骨密度值显著高于骨质疏松组[(352±16),(233±14)mg/cm2,P<0.01]。③骨量正常组跟骨平均骨小梁间距或弥散度低于骨质疏松组而松质骨体积高于骨质疏松组(P<0.05)。④超声振幅衰减平均值和骨硬度指数与骨密度呈直线正相关(r=0.814,0.326,P<0.01,0.05)。⑤超声传播速度与骨小梁游离末端、平均骨小梁间距呈直线负相关(r=-0.688,-0.712,P<0.01),与小梁间连点数、松质骨体积呈直线正相关(r=0.672,0.794,P<0.01);骨硬度指数与平均骨小梁间距呈直线负相关(r=-0.358,P<0.05),与松质骨体积呈直线正相关(r=0.513,P<0.01)。结论:跟骨定量超声测量中,超声振幅衰减平均值能较好地反映骨的密度,超声传播速度能较好地反映骨的质量,而骨硬度指数能较综合地反映骨强度的改变。  相似文献   
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