Test of internal-conversion theory with precise gamma- and X-ray spectroscopy.

Precise measurements of K-shell internal conversion coefficients (ICCs) are being used to determine the best method for calculating these coefficients. A recent result for the M4 transition from 193Irm has been refined, demonstrating conclusively that the atomic vacancy created by the ejected electron must be properly accounted for in the calculation of ICCs. Measurements of additional cases are discussed.     

K/LM+ internal-conversion ratios for pure E2 transitions in the decays of 152Eu and 192Ir

Measurements have been made with a magnetic β-ray spectrometer in order to determine the internal-conversion ratio R = K/LM+ for pure E2 transitions of 244.7 and 344.3 keV in the decay of ¹⁵²Eu and of 205.8 and 316.5 keV in the decay of ¹⁹²Ir. The results from several experimental runs for each transition are respectively, R = 2.92 ± 0.05, 3.43 ± 0.05, 1.05 ± 0.04 and 1.71 ± 0.05. A comparison has been made with previously published results as well as with theoretical values deduced for pure E2 multipolarity from the most recent tabulations of internal-conversion coefficients.     

大肝癌的精确化疗栓塞

目的 探讨大肝癌肝动脉精确化疗栓塞的临床价值.方法 对80例大肝癌患者运用微导管对肿瘤的滋养动脉进行段性或亚段性精确化疗栓塞.评价病灶的碘油沉积情况、介入术后肝功能的恢复、生活质量及生存时间.结果 80例大肝癌患者经过精确化疗栓塞后,全部病例碘油沉积良好、肿块缩小,肝功能及生活质量得到改善,10例患者取得了手术机会.20例Child-Pugh B级经过末次治疗后16例肝功能恢复为Child-Pugh A级,50例Child-Pugh A级治疗后肝功能仍保持无明显变化.1年生存率86.67%,2年生存率63.33%,3年生存率33.33%,4年生存率6.67%,5年生存率3.30%.结论 基于微导管技术的大肝癌精确化疗栓塞,在改善患者的肝功能、提高生活质量、延长生存期及提高根治率方面具有重要的意义.     

Precise biopsy localization by computer tomography.

The ultimate accuracy of percutaneous needle aspiration and core biopsies is directly related to localization of pathology and of the needle tip. Localization methods currently in use include fluoroscopy, ultrasound, and angiography. The authors believe that localization by computed tomography is the single most accurate method for performing biopsies.     

A Precise Approach to Anterior Knee Pain

I brief Accurate diagnosis and specific treatment will lead to a good outcome for most patients who have anterior knee pain. The most common etiologies are patellar tracking disorders and instability; chondral and osteochondral disorders; tendinitis, bursitis, and synovitis; and traction apophysitis. Most of these can be treated conservatively with nonsteroidal anti-inflammatory medications, flexibility and strengthening exercises, moist heat before exercise and ice afterward, and various types of knee sleeves.     

Precise emission probabilities of gamma-rays of 159Gd.

Measurement of emission probabilities for principal gamma-rays of 159Gd with 4pibeta(ppc)-gamma(HPGe) coincidence apparatus has given precise values as indicated by uncertainties of about 1%. Improved certainties are seen when comparing the present results with emission probabilities evaluated in Nuclear Data Sheets (Helmer, 1994, p. 72) for which the uncertainties are about 24%. The improvement resulted in precise decay scheme parameters of the nuclide.     

Precise placement of sphenoidal electrodes via fluoroscopic guidance.

Fluoroscopically guided placement of sphenoidal electrodes for the assessment of epileptiform activity in the mesial-basal-temporal lobes offers distinct advantages over standard techniques, such as more precision in placement, reduced likelihood of facial pain, and fewer complications (vessel perforation or nerve injury). We describe our instrumentation, technique, and results in over 40 patients.