An evaluation of transverse axial emission tomography of the brain in the clinical situation

The Aberdeen section scanner provides, in addition to conventional views, a display of the distribution of radioactivity in a tomographic section of the brain. This paper examined the value of this additional information. Scans of lesions confirmed pathologically or radiologically, along with normal and doubtful cases, were examined after a careful randomization procedure. During the course of the study each set of conventional views was examined twice, once without and once with a tomographic section view. In two out of 29 cases (7%) the lesion was diagnosed only with the aid of the tomographic section scan. Improved accuracy of diagnosis with the tomographic section view was significant at the 1% level or better.     

MR imaging in pretruncal nonaneurysmal subarachnoid hemorrhage: is it worthwhile?

BACKGROUND and PURPOSE: The cause of pretruncal (perimesencephalic) nonaneurysmal subarachnoid hemorrhage is not known. MRI of the brain or spine is often performed to exclude any other vascular abnormalities. Its diagnostic value is not known. METHODS: We used MR imaging of the brain with routine sequences, gadolinium enhancement, and additional thin T1-weighted axial sections following a triple dose of contrast. RESULTS: We performed MR imaging of the brain in 18 patients with a pretruncal nonaneurysmal subarachnoid hemorrhage. The focal nature of the subarachnoid hemorrhage exclusively in front of the brain stem was confirmed in 14 patients studied within 7 days of the ictus. No vascular abnormalities were found in 17 cases, including 14 patients with gadolinium enhancement. An incidental capillary telangiectasia was found in 1 patient. Fluid-attenuated inverse recovery MR additionally documented blood in the sulci due to cerebrospinal fluid recirculation of blood. Five patients underwent MR imaging of the spine, and no arteriovenous malformations were found. CONCLUSIONS: MR imaging did not reveal a source of pretruncal subarachnoid hemorrhage. The cost of MR imaging probably outweighs the benefit in the evaluation of this variant of subarachnoid hemorrhage.     

Induction of cytotoxic T lymphocytes by recombinant canarypox (ALVAC) and attenuated vaccinia (NYVAC) viruses expressing the HIV-1 envelope glycoprotein

Successful immunization against many viruses, including retroviruses such as HIV-1, is thought to depend upon the roles of both antibody and cytotoxic T-lymphocyte responses. With safety a major concern, we developed two poxvirus recombinants expressing the envelope glycoprotein of HIV-1 IIIB. Canarypox (ALVaC), which is not known to replicate in mammalian cells, and a highly attenuated vaccinia (NYVAC) virus deleted of 18 open reading frames associated with virulence and host range were used as vectors. Upon inoculation into BALB/c mice, both the ALVAC and NYVAC recombinants were capable of inducing antibody responses to HIV gp120 and provoking remarkable levels of primary and memory Thy1.2+, CD4-, CD8+ cytotoxic T-lymphocyte responses to the hypervariable V3 loop of the HIV-1 envelope glycoprotein.     

Comprehensive analysis of results of surgical treatment of oral tongue carcinoma in Hong Kong

OBJECTIVE: To evaluate the results of primary surgical treatment of carcinoma of oral tongue in Hong Kong. METHODS: Patients who had undergone primary surgical treatment of oral tongue carcinoma in Queen Mary Hospital were reviewed. RESULTS: There were 112 patients in this study. The first sites of tumor recurrence were 10 (9%) local, 25 (22%) nodal, 3 (3%) locoregional, 5 (5%) distant, 1 (1%) local and distant, 3 (3%) nodal and distant, and 1 (1%) neck extranodal site. Of the 63 T1-2 N0 M0 patients, the regional recurrence rate was 9% for elective neck dissection compared with 47% for "watchful waiting" (Chi-square test, P = 0.0008). The regional recurrence related mortality was 3% for elective neck dissection compared with 23% for "watchful waiting" (Fisher's test, P = 0.02). The 5-year actuarial survival rate was 86% for elective neck dissection compared with 55% for "watchful waiting" (Wilcoxon, P = 0.01). CONCLUSIONS: Local and regional recurrences were the main sites of treatment failure. Elective neck dissection has significant benefits in the reduction of regional failure and improvement of survival. Elective selective I-III neck dissection have to be considered in patients with stage I and stage II oral tongue carcinoma.     

关于实施《农药剂型名称及代码》国家标准应注意的几个问题

《农药剂型名称及代码》(GB/T 19378-2003)国家标准已于2004年4月1日实施。本标准参照了国际上的《农药标准》(FAO，1999)、《卫生用农药标准》(WHO，1997)、《家用杀虫剂产品的标准指南》(WHO，1998)和《农药剂型代码及国际代码系统》(GCPF，1989)等资料，并以FAO的农药分类法为蓝本。标准的内容涵盖了国内卫生用药和植物保护用药方面所有120种农药剂型，并说明了制定剂型代码的基本原则。对某些对于剂型和代码认识欠妥的案例举例做出了说明。某些不恰当的剂型名称将根据本代码系统加以改正，附表中列出了新旧名称对照。     

Formation polarity dependent improved resistive switching memory characteristics using nanoscale (1.3 nm) core-shell IrOx nano-dots

ABSTRACT: Improved resistive switching memory characteristics by controlling the formation polarity in an IrOx/Al2O3/IrOx-ND/Al2O3/WOx/W structure have been investigated. High density of 1 × 1013/cm2 and small size of 1.3 nm in diameter of the IrOx nano-dots (NDs) have been observed by high-resolution transmission electron microscopy. The IrOx-NDs, Al2O3, and WOx layers are confirmed by X-ray photo-electron spectroscopy. Capacitance-voltage hysteresis characteristics show higher charge-trapping density in the IrOx-ND memory as compared to the pure Al2O3 devices. This suggests that the IrOx-ND device has more defect sites than that of the pure Al2O3 devices. Stable resistive switching characteristics under positive formation polarity on the IrOx electrode are observed, and the conducting filament is controlled by oxygen ion migration toward the Al2O3/IrOx top electrode interface. The switching mechanism is explained schematically based on our resistive switching parameters. The resistive switching random access memory (ReRAM) devices under positive formation polarity have an applicable resistance ratio of > 10 after extrapolation of 10 years data retention at 85°C and a long read endurance of 105 cycles. A large memory size of > 60 Tbit/sq in. can be realized in future for ReRAM device application. This study is not only important for improving the resistive switching memory performance but also help design other nanoscale high-density nonvolatile memory in future.     

智能家居情境感知服务的运行时建模与执行方法

随着智能家居基础设施的不断发展,智能家居逐渐进入以智能服务为特征的新时期.大量复杂、异构的智能设备相互协同,构成海量、智能、集成的智能家居应用.其中,情境感知服务根据服务对象所处情境的变化为其提供准确的服务,是智能家居应用的典型代表.目前,情境感知服务往往面向场景进行构建,其设备多样性和服务随需性给应用开发带来极大的挑战.开发者需要熟悉设备管理接口、进行接口调用和交互,同时,理解服务功能和质量需求,进行管理逻辑的编写.为了快速定制和开发情境感知服务,将知识图谱引入开发过程,提出一种智能家居情境感知服务的运行时建模与执行方法：首先,提出智能家居情境感知服务知识图谱概念模型,定义其情境中各种概念和关系;其次,提出智能家居情境感知服务知识图谱实例模型的构造与维护机制,通过运行时概念、关系实例表示情境知识;最后,提出基于知识推理的智能家居情境感知服务执行方法,通过知识推理自动执行设备功能.面向实际场景,构建智能家居原型系统.实验结果显示,该方法能够实现情境感知服务运行时建模与执行,其代码减少量超过90%.     

基于纳米金/铜有机骨架的酶传感器检测蔬菜中敌敌畏

目的 制备氨基化纳米金/铜有机骨架(aminated gold nanoparticles/copper-origin frameworks,AuNPs-NH₂/Cu-MOF)纳米复合材料,并构建新型乙酰胆碱酯酶(acetylcholinesterase,AChE)传感器对蔬菜中敌敌畏进行定量分析。方法 采用羧甲基壳聚糖(carboxymethyl chitosan,CMCS)为交联剂,AuNPs-NH₂/Cu-MOF为修饰材料,玻碳电极(glassy carbon electrode,GCE)为工作电极,构建AChE/AuNPs-NH₂/Cu-MOF/GCE传感器。通过对交联剂、酶固载量、抑制时间的优化,确定传感器的最佳工作条件,对蔬菜中敌敌畏进行检测分析。结果 AuNPs-NH₂/Cu-MOF不仅具有良好的导电性和生物相容性,还可以为酶和底物提供更多的接触位点,有效地提高传感器的灵敏度。在最佳工作条件下,在1.0×10^-10～1.0×10^-5 g/L之...