Radiotherapy alone in breast cancer. I. Analysis of tumor parameters, tumor dose and local control: the experience of the Gustave-Roussy Institute and the Princess Margaret Hospital

This retrospective study involved 463 breast cancer patients treated by radiotherapy alone at the Princess Margaret Hospital and at the Institut Gustave-Roussy. These patients either had operable tumors, but were unfit for general anesthesia, or had inoperable tumors due to local contraindications to surgery. Results were analyzed according to tumor response, local recurrence rate, tumor size, tumor fixation, nodal fixation and tumor dose. Conventional statistical analysis of local control showed two significant factors: tumor dose and tumor size. Multivariate analysis permitted to define an "individual risk" (IR) of local recurrence according to three independent factors: tumor size, tumor fixation, and nodal fixation. It was shown that the IR was a good prognostic factor for local control. Increase in tumor dose gave a similar effect in the local recurrence relative risk for all the IR groups. According to the slope of the dose-effect curve, it was deduced that a dose increase of 15 Gy can decrease the relative risk of local recurrence 2-fold. In fact, it was shown that tumor dose was the most significant independent factor on local control, able to produce up to a 10-fold increase compared to 2-fold decrease for tumor size. If the IR of local recurrence is known, a theoretical predictive value on local control, taking into account the tumor dose, can be determined according to the present data.     

Certain characteristics of myocardial contractility of isovolumic dog heart at randomly variable heart rhythm

Summary The relationship heart rate-left ventricular pressure was investigated in the isolated canine heart perfused with constant pressure at different preloads. Rhythmical stimulation was performed with constant stimulus interval duration and with stimulus intervals randomly changed near the average value (150–200 stimuli in series).Correlation and dispersion function analysis show that rhythm dispersion had a negative inotropic effect which was independent of the preload of the ventricle in the range of 120–180 beat/min, but this dependence occurred with low rates of stimulation.This method is proposed for the assessment of contractility under conditions of heart rate variations (physiological and pathological arrhythmias).     

Relationship between the ocular and systemic disposition of flurbiprofen: The effect of altered protein dynamics at steady state

The differences in flurbiprofen disposition in the aqueous humor and the plasma were examined after systemic doses. Steady state plasma concentrations of flurbiprofen (20–60 g/mL) were achieved via intravenous infusion to albino rabbits. Flurbiprofen demonstrated linear systemic kinetics throughout the dosing range, with constant body clearance and unbound fraction in plasma. At steady state, aqueous humor drug concentrations depended on the corresponding plasma drug concentration. Two clearance terms—CL_so, the systemic clearance to ocular tissues, and CL_os, the ocular clearance to systemic circulation—were used. After systemic doses, the drug concentration in the aqueous humor was related to that in the plasma as well as to the ratio of these two clearances. Flurbiprofen was extensively bound to plasma proteins and showed limited ocular distribution; its CL_so to CL_so tratio was very small. Thus, the concentration of flurbiprofen in the aqueous humor after systemic doses was lower than that obtained after ophthalmic doses. A plasmapheresis technique was utilized to lower the plasma protein concentrations to 60% of normal levels. As a consequence, flurbiprofen demonstrated reduced aqueous humor protein concentrations, increased unbound fractions in the plasma and the aqueous humor, elevated aqueous humor drug concentrations, and elevated total body clearance. The unbound body clearance stayed unchanged. Our study indicated that a drug should present a significant CL_so/CL_os ratio in order to achieve therapeutic concentrations in the eye via systemic doses. The drug-protein binding kinetics can be different between the plasma and the aqueous humor circulations. Because the ocular compariment is very small compared to the overall systemic distribution of flurbiprofen, it has little effect on the steady state systemic concentrations.     

对医院办公室工作的思考

面对医疗卫生事业改革的新形势、新任务,医院办公室应该更新观念,树立改革创新意识、大局意识、法制意识、市场竞争意识和以病人为中心的意识;积极参与医院改革、成本核算、组建医疗集团、建立医院信息系统、开拓医疗服务市场、参与市场竞争等医院重点工作;建立和协调好对内对外的关系,在医院改革与发展中发挥积极作用。     

广山楂HPLC指纹图谱建立及其活血化瘀作用谱效关系研究

目的 建立广山楂Malus doumeri指纹图谱,测定各批次广山楂的“活血化瘀”药效学指标,探讨广山楂化学成分与活血化瘀功效的谱效关系。方法 采用HPLC法建立18批广山楂的指纹图谱。利用大鼠高脂模型,测定不同批次广山楂的“活血化瘀”药效学指标,包括高密度脂蛋白胆固醇（high density lipoprotein cholesterol,HDL-C）、低密度脂蛋白胆固醇（low density lipoprotein cholesterin,LDL-C）、总胆固醇（total cholesterol,TC）、三酰甘油（triglyceride,TG）含量及血液流变学指标等。运用偏最小二乘回归法（partial least-square method regression,PLSR）、灰色关联度分析法,分析广山楂化学成分与活血化瘀药效指标间的谱效关系。结果 构建了广山楂的HPLC图谱,确定了6个共有峰,并指认了其中的2个共有峰（绿原酸、根皮苷）。活血化瘀实验表明,不同批次广山楂活血药效指标间具有明显差异,在标定的广山楂6个特征峰中,峰2～6与HDL-C呈正相关,峰1、5、6与LDL...     

槲皮素的结构修饰及生物活性研究进展

槲皮素是蔬菜、水果、中药中常见的黄酮类化合物,是天然的抗氧化剂,具有抗癌、抗糖尿病、抗菌、抗炎、抗病毒等生物活性。由于槲皮素生物利用度低,限制了其在临床上的应用。通过各种方法设计和合成新的槲皮素衍生物,以改善其缺点,进而发挥预防和治疗疾病的作用。通过对槲皮素衍生物的合成及其抗癌、抗糖尿病、抗炎、抗菌和抗病毒活性进行综述,并对其构效关系进行分析,为天然化合物的开发和利用奠定基础。     

新型三唑苄胺类化合物体外抗真菌活性及构效关系

目的：研究23个1－[2－（N－甲基－N－取代苄基）氨基－2（2,4－二氟苯基）乙基]－1H－1,2,4－三唑类化合物的体外抗真菌活性,并初步探讨其构效关系。方法：选择8种临床致病真菌为试验菌,观察本类化合物对它们的体外抑菌作用,并与布替萘芬和益康唑作比较。结果和结论：所有目标化合物对8种试验真菌均有不同程度的抑制作用,大部分化合物对白念珠菌和近平滑念珠菌的活性明显高于布替萘芬;化合物2、13对新型隐球菌的活性是益康唑的64－128倍,化合物2、3、13、16对多数真菌显示较强活性。构效关系研究表明,苄胺类和氮唑类化合物的特征结构组合在一起,对某些真菌的抑菌活性起到了取长补短的作用;但苄基为萘苄时,对多数深部真菌活性较差。     

迷宫学习模型实验的时反应量-效关系

目的　分析学习记忆动物行为模型实验的时反应量 效关系指标。方法　应用Y型迷宫刺激器对大鼠进行空间学习记忆的行为模型实验。结果　测得大龄组 (约 12月 )和小龄组 (<4月 )大鼠达到学会标准前所需的刺激次数分别为 (32 .6 2± 2 0 .5 9)次 (n =2 1)和 (2 0 .6 2± 14.2 5 )次 (n =2 1,P <0 .0 5 ) ,学会时 9次正确反应的潜伏期分别为 (7.44± 2 .89)s和 (6 .93± 1.49)s(P >0 .0 5 ) ,并观察到刺激次数与逃避到安全区的潜伏期呈类双曲线型时反应量 效关系、刺激次数与移动正确率呈非线性正变关系。结论　迷宫学习模型实验存在特殊类型的时反应量 效关系。     

医学伦理学教学模式探讨

医学伦理学是医学科学和伦理学科学交叉的边缘科学 ,是医学道德的科学 ,是一般伦理学原理在医学实践中的具体运用。培养合格医学生 ,不仅要注重医学知识的教育 ,而且要重视医学伦理道德的引导和培养。本文从教育的目的、原则、内容及教学方法等方面探讨医学伦理学的教学模式 ,旨在从理论到实践提高医学生的医德修养