非溶蚀型药物体系的释放动力学新模型──Fick第一扩散定律的修正及其应用

基于以下两点事实:Fick第一扩散定律中的扩散系数并非严格的常数,它随浓度变化;Fick第一扩散定律只适用于浓度梯度恒定的稳定扩散,而许多实验表明浓度梯度也是一个时间函数,本文对Fick第一扩散定律作出两点修正将原定律中浓度梯度和扩散系数分别修正为时间函数和浓度函数,从而导出关于非溶蚀型药物体系的释放动力学模型。该模型较其他常用释放模型有更好的拟合效果,其参数也有较为明确的物理意义。     

Interstitial hyperthermia in combination with brachytherapy

Flexible coaxial cables were modified to serve as microwave antennas operating at a frequency of 915 MHz. These antennas were inserted into nylon afterloading tubes that had been implanted in tumors using conventional interstitial implantation techniques for iridium-192 seed brachytherapy. The tumor volume was heated to 42-45 degrees C within 15 minutes and heating was continued for a total of 1 hour per treatment. Immediately following a conventional brachytherapy dose and removal of the iridium seeds the tumors were heated again in a second treatment. This interstitial technique for delivering local hyperthermia should be compatible with most brachytherapy methods. The technique has proved so far to be practical and without complications. Temperature distributions obtained in tissue phantoms and a patient are described.     

Value of plasma calcium, phosphate, and alkaline phosphatase measurements in the diagnosis of histological osteomalacia

Plasma calcium and phosphate concentrations and alkaline phosphatase activities were examined retrospectively in 50 patients with histologically proven osteomalacia and 50 age- and sex-matched control subjects with normal bone histology. An abnormal plasma alkaline phosphatase activity was more useful than an abnormal plasma calcium or phosphate concentration in distinguishing between normal and osteomalacic subjects, producing a false-negative rate of 14% and a false-positive rate of 8%. False-negative and false-positive rates of 10% and 8% respectively were obtained when the presence of an abnormality in any one of the three biochemical measurements was used as a predictor of histological osteomalacia. When discriminant analysis was applied to plasma calcium, phosphate and alkaline phosphatase together a false-negative rate of 12% and a false-positive rate of 0% was obtained.     

变价态唐松草新碱—PVC膜离子选择电极的研制及解离常数的测定

本文研制了以四苯硼—唐松草新碱缔合物为电活性物质的变价态唐松草新碱—PVC膜电极。电极膜按电活性物质:PVC:DBP为1:8:8组成。该电极在pH 5.0～6.0,Ⅰ=0.05的NaCl—HCl溶液中Nernst响应范围为1×10^-3～1×10^-5mol/L。电极斜率为58.2 mV/logc。检测限为2.5×10^-6mol/L。用直接电位法考察了TDH⁺,TDH₂CF⁺⁺共存时溶液pH和电极斜率S的关系。用S—pH关系,测定了25℃,Ⅰ=0.05时的Ka₁值为(2.5±0.2)×10^-4,用E—pH关系,测定了25℃,Ⅰ=0.05时的Ka₂值为(8.1±0.9)×10^-8。     

Utilizing Nottingham Prognostic Index in microarray gene expression profiling of breast carcinomas.

We report a novel approach to gene expression profiling using the Nottingham Prognostic Index (NPI) to stratify 26 patients with invasive breast carcinoma. As an aggregate index of parameters reflecting metastatic potential, growth rate, and genetic instability the NPI has distinct advantages over other clinicopathologic features used to segregate breast cancer patients. As a continuous variable it offers a responsive and sensitive means of modeling a continuum of clinical aggressiveness. Using RNA extracted from 26 tumors and cDNA microarrays with 23 343 unique genetic elements, 84 genes and expressed sequence tags were identified whose expression patterns correlated with NPI. Differential expression by immunohistochemistry (IHC) was also observed for two of three genes evaluated by this method. Correlation was determined by the Spearman rank correlation method with null distribution analysis. Among the 84 genetic elements were seven previously implicated in neoplastic progression (including the two demonstrating differential expression by IHC), 11 without specific cancer association but localized to chromosomal sites whose loss or gain has been identified in cytogenetic studies of breast carcinoma, and 73 not previously associated with breast carcinoma. Collectively, the expression patterns of these 84 elements have potential to distinguish high and low NPI patient samples. These data add support to the assertion that prognostic groups of breast carcinoma are reflected in distinguishable expression profiles of a limited set of genes.     

Physiology of sucking in the normal term infant using real-time US

Our study of 16 normal term, breast-fed infants documents real-time ultrasound as a technique for evaluating the oral portion of the sucking mechanism in infants. We also describe the mechanics of sucking used by the infants during breast-feeding.