Improved prediction of bone mineral content and density

To establish improved predictive values for normal bone mineral content (BMC) and density (BMD) in adolescent girls a community based study of schoolgirl volunteers was carried out by dual energy x ray absorptimetry. Measurements were performed on 216 subjects aged 11.0 to 17.9 years; measurements were repeated one year later on 84 of the girls, providing a total of 300 studies. For total body BMC the standard error of the prediction was improved from 290.9 g to 134.1 g when weight, height, and shoulder width were added to the normal variable of age. For spine BMD the standard error of the prediction was improved from 0.105 g/cm2 to 0.066 g/cm2 when height, weight, and shoulder width were added to the normal variable of age. Significant improvements were also obtained for total BMD and spine BMC. Despite the normal practice of predicting bone density from age alone this was not selected as the first variable in a multiple stepwise regression for either total body or spine. The prediction of BMC and BMD can be significantly improved by the inclusion of simple body habitus parameters in the prediction equations. As the mean (SE) z score derived from the manufacturer's normal data was - 0.36 (0.02) these American data are probably not appropriate for use in adolescents in the UK.     

Staghorn calculi: endourologic management in 120 patients

Symptomatic staghorn renal calculi were removed from 106 of 124 kidneys (85%) with percutaneous ultrasonic lithotripsy. All remaining fragments were less than 5 mm in greatest diameter, small enough to pass spontaneously. Use of two or more access routes was necessary in 91 kidneys (73%), and 29 patients (24%) required multistage nephrolithotripsy for complete stone removal. The total operative time averaged 162 minutes per patient. The average hospitalization period was 12.5 days, and the average convalescence time after discharge was 15 days. The most common adverse effect was bleeding necessitating transfusion (57%). Infection occurred in 27% of patients and may be intrinsic to removal of these infected stones. There was one death in the study group: a patient with multiple medical problems died of myocardial infarction. Successful stone extraction requires a clear understanding of renal anatomic features, properly placed access routes, and radiologic-urologic expertise. It is concluded that staghorn calculi can be safely and effectively treated with the use of percutaneous techniques.     

胆红素IXα在碱溶液中的荧光性质和异构化作用

研究了朋红素IX_α的荧光性质,发现胆红素IX_α在碱溶液中有较强的特征荧光,考察了影响胆红素碱溶液荧光性质及其稳定性的因素,时间扫描的荧光动力学研究表明胆红素IX_α碱溶液在30min内有足够稳定的强荧光信号,这对建立胆红素的荧光分析方法有重要意义。从胆红素IX_α的碱溶液中分离出荧光活性物,结构分析认为是胆红素IX_α的某一异构体。讨论了胆红素IX_α的异构化作用与胆红素IX_α碱溶液荧光性质的变化规律。     

Renal calculi: sensitivity for detection with US

The sensitivity of sonography in the detection of renal calculi was tested in a three-phase study in 100 patients. In phase 1, ultrasonographic (US) scanning was performed after review of abdominal radiographs and renal tomograms in 30 patients who had undergone extracorporeal shock wave lithotripsy (ESWL). In this group the sensitivity of US for detecting stones was 98%. In phase 2, scanning was performed in 30 post-ESWL patients without prior review of radiographs or tomograms. The sensitivity of US for stone detection in this group was 95%. In phase 3, sonography was performed in a blinded fashion on a random mix of post-ESWL patients and patients who had undergone urography for reasons unrelated to nephrolithiasis. The sensitivity of US for stone detection in this group of 40 patients was 91%. The overall sensitivity in all three groups was 96%, which was superior to the performance of abdominal radiography and slightly inferior to the combination of abdominal radiography and renal tomography. The ability to detect kidney stones with US depended on stone size but was independent of stone location or patient size. The study findings suggest that US is an effective means for detecting kidney stones in patients with suspected nephrolithiasis.