海湾战争后电子战发展新动向

本文首先报导了海湾战争后美国电子战装备发展计划、采办策略及情报机构的调整情况,尔后从正在研制的综合电子战系统升空平台电子战装备、平台外电子战设备、导弹迫近告警系统等方面分析了国外电子战发展的新趋势,最后论及了电子战的重新定义。     

Prediction of nasal obstruction based on clinical examination and acoustic rhinometry

Mandibulofacial dysostosis is readily recognized on the basis of a characteristic facial appearance caused by hard and soft tissue abnormalities of the face, including malformations of the ear. Generally, the abnormality is symmetrical. The psychological and social stigma associated with severe facial deformity makes this syndrome one of the most challenging reconstructive problems presented to the craniomaxillofacial surgeon.     

High levels of interleukin-6 are associated with low tumor burden and low growth fraction in multiple myeloma

Interleukin-6 (IL-6) is a multifunctional cytokine postulated to play a central role as a growth factor for multiple myeloma (MM). We evaluated the spontaneous secretion of IL-6 in supernatants of Ficoll-Hypaque--enriched bone marrow (BM) cultures from 35 patients with MM. The levels of IL-6 were correlated with biological and clinical characteristics of the disease. High levels of IL-6 production defined a subgroup of patients with low tumor burden as determined by lower serum beta 2-microglobulin (B2M) (P = .02) and lower percentage of myeloma cells infiltrating the bone marrow (P = .003), higher synthetic rates of monoclonal protein (P = .006), and low proliferative compartments as measured by the percentage of Ki-67--positive myeloma cells. Patients with high proliferative fractions (Ki-67--positive myeloma cells > 20%) had significantly lower levels of IL-6 when compared with patients with low proliferative fractions (P = .005). Our findings do not support IL-6 as a major growth factor for MM, but demonstrate an association of high levels of IL-6 secretion with low tumor cell burden and low proliferative fraction.     

Parameters of estrogen expression in patients with endometrial tumors as prognostic signs of the effectiveness of neoadjuvant antitumor hormone therapy

Comparison was made of changes in such morphological characteristics of tumor as cell differentiation and mitotic activity in 142 patients with endometrial carcinoma in the course of treatment, using tamoxifen or oxyprogesterone capronate or both, and those of estrogen background (karyopicnotic, eosinophilic and maturity indices, numerical index of maturity and blood-estradiol level). Three levels of estrogen background-low, medium and high-were identified by assay of the colpocytological indices in postmenopausal patients with endometrial carcinoma. Levels of the colpocytological indices observed at high indices of estrogen background proved a reliable numerical criterion for evaluating the sensitivity of the patients to neoadjuvant hormone therapy. A significant correlation was established between high estrogen background, pathogenetic variant I and high differentiation of tumor cells. The high incidence of hormonal pathology in tumor tissue was registered when the colpocytological indices dropped by half after oxyprogesterone capronate treatment, and by third-after combined therapy (tamoxifen + oxyprogesterone capronate). In cases free from pronounced pathomorphism, said indices dropped by not more than 20%.     

Wave speed during maximal expiratory flow and phase velocity from forced oscillations

We review currently known results concerning the estimation of an 'immune' or 'cured' proportion, and testing for the presence of immunes, in censored survival data, suggesting that a firm theoretical foundation now exists for analysis. Two types of estimators, parametric and non-parametric, are discussed and compared with respect to their theoretical properties, and, by simulation, with respect to their small sample behaviour. Both estimators have advantages and drawbacks, but together provide powerful tools for the perceptive analysis of survival data with, or even without, immune individuals.     

使用无线电集群通信系统应扬长避短

本文先对集群通信系统的概念作一些阐述,包括其含义、特点和一些主要功能。对集群方式的三种形式——消息集群、传输集群和准传输集群作了简要介绍。对集群系统的两种控制方式——专用控制信道方式和非专用控制信道方式也作了简单分析。在此基础上,对集群通信系统的正确使用提出了看法,对蜂窝和集群两个系统作了简要比较。