细胞信号传导理论的建立及其启示

细胞信号传导理论的提出 ,极大地深化了以往对细胞生物学的认识。该理论在形成和发展的过程中 ,移植嫁接了信息科学的新原理和新方法 ,促进了人类对复杂的生命系统的研究和了解 ,同时这种移植嫁接使生命现象及其规律的研究反过来为生物电子学及生物信息学的进一步发展奠定了良好的基础 ,加速了生物电子学和生物信息学时代的到来     

对JFET顶、背栅电位稳定技术分析

在JFET作输入管的低噪声高精度运放中，为了进一步减小输入偏流，增大输入阻抗，可使顶、背栅分离，且仅以顶栅接片内的控制电路。本文主要对JFET背栅电平进行动态稳定控制的电路进行分析。     

Risk Assessment of Nongenotoxic Carcinogens Based upon Cell Proliferation/Death Rates in Rodents

Increased cell proliferation increases the opportunity for transformations of normal cells to malignant cells via intermediate cells. Nongenotoxic cytotoxic carcinogens that increase cell proliferation rates to replace necrotic cells are likely to have a threshold dose for cytotoxicity below which necrosis and hence, carcinogenesis do not occur. Thus, low dose cancer risk estimates based upon nonthreshold, linear extrapolation are inappropriate for this situation. However, a threshold dose is questionable if a nongenotoxic carcinogen acts via a cell receptor. Also, a nongenotoxic carcinogen that increases the cell proliferation rate, via the cell division rate and/or cell removal rate by apoptosis, by augmenting an existing endogenous mechanism is not likely to have a threshold dose. Whether or not a threshold dose exists for nongenotoxic carcinogens, it is of interest to study the relationship between lifetime tumor incidence and the cell proliferation rate. The Moolgavkar–Venzon–Knudson biologically based stochastic two-stage clonal expansion model is used to describe a carcinogenic process. Because the variability in cell proliferation rates among animals often makes it impossible to detect changes of less than 20% in the rate, it is shown that small changes in the cell proliferation rate, that may be obscured by the background noise in rates, can produce large changes in the lifetime tumor incidence as calculated from the Moolgavkar–Venzon–Knudson model. That is, dose response curves for cell proliferation and tumor incidence do not necessarily mimic each other. This makes the use of no observed effect levels (NOELs) for cell proliferation rates often inadmissible for establishing acceptable daily intakes (ADIs) of nongenotoxic carcinogens. In those cases where low dose linearity is not likely, a potential alternative to a NOEL is a benchmark dose corresponding to a small increase in the cell proliferation rate, e. g., 1%, to which appropriate safety (uncertainty) factors can be applied to arrive at an ADI.     

植物原生质体培养及应用

综述了原生质体培养的研究进展,原生质体培养在理论上和品种改良中的应用。在理论研究中的应用有三个方面：1、细胞生理现象的研究;2、细胞核与细胞质相互关系的研究;3、病毒侵染与复制机理的研究。在品种改良中的应用采用的方法包括二个方面：1、遗传操作;2、突变体的筛选。     

贴体网格生成技术中正交性和空间疏密控制研究

在综合阐述网格生成技术对流场数值计算重要性的基础上,提出了一种非周期性叶栅流场网格的数值生成方法。该方法对任意曲线（面）边界生成正交性思想的网格具有普适性,且可以对整个区域网格的正交性进行有效的控制。此外,本文还对网格正交性和疏密分布之间的关系进行了探讨,给出了影响网格正交性的因素和改进方法。     

Carcinogenicity Studies on MTBE: Critical Review and Interpretation

Chronic inhalation of toxic concentrations of MTBE caused renal tubular cell neoplasms in male Fischer 344 rats and hepatocellular adenomas in female CD-1 mice. In Sprague-Dawley rats the oral administration of MTBE was associated with increased incidences of Leydig cell tumors and of lymphomas and leukemias (combined) in males and females, respectively. Neither lymphomas nor leukemias were individually increased in treated females. Leydig cell tumors are common in rats and do not predict human responses to drugs and chemicals. Neither MTBE nor its metabolite, t -butyl alcohol, possess mutagenic potential and a second metabolite, formaldehyde, is mutagenic in vitro but in vivo results are equivocal. MTBE-induced neoplasms are most likely produced through a nongenetic mechanism which requires chronic exposure to toxic doses. Because of the intense odor (and taste) of MTBE, humans will not tolerate either air or water concentrations sufficient to produce the cytotoxic precursors required to promote cellular proliferation.     

Pseudo-Youden designs balanced for intersection

If the row-column intersections of a row-column design A form a balanced incomplete block design, then A is said to be balanced for intersection. This property was originally defined for triple arrays by McSorley et al. (2005a), Section 8, where an example was presented and questions of existence were raised and discussed. We give sufficient conditions for the class of balanced grids in order to be balanced for intersection, and prove that a family of binary pseudo-Youden designs has this property.     

手机铃声下载的著作权问题

手机铃声下载作为一种新型网络服务方式引发了一系列相关的著作权问题。通过对一起典型案例的分析,指出未经许可使用音乐作品作为手机铃声供人下载侵犯了作者的信息网络传播权,但是应当由网络内容提供商而非网络服务商承当由此产生的赔偿责任。此外,应当以合理方式确定著作权集体管理组织的相关收费标准,以促进作者利益与社会公共利益之间的平衡。     

基于XML的企业ERP商务智能系统研究

扩展标记语言（Extensible Markup Language,XML）是一种简单的用来描述数据及数据存储的语言,由万维网协会创建,用来克服HTML语言的局限性,论文就XML在企业ERP系统商务智能实现过程中的应用进行了探究,并最终形成模型。     

Effects of testosterone replacement therapy on hypogonadal men with osteopenia or osteoporosis: a subanalysis of a prospective randomized controlled study in Japan (EARTH study)

Objective: We investigated the effects of testosterone replacement therapy (TRT) on bone mineral density (BMD) among hypogonadal men with osteopenia/osteoporosis.

Methods: From our previous EARTH study population, 74 patients with a clinical diagnosis of osteopenia or osteoporosis and hypogonadism were included in this study, as the TRT (n?=?35) and control (n?=?34) groups. The TRT group was administered 250?mg of testosterone enanthate injection every 4 weeks for 12 months. The BMD, waist circumference, body mass index, body fat percentage, and muscle volume were measured at baseline and at 12 months. Blood biochemical data, including total cholesterol, triglycerides, HDL-cholesterol, hemoglobin A1c, and adiponectin values were also evaluated.

Results: At the 12-month visit, BMD significantly increased in both groups. However, comparisons on changes of parameter values from baseline to the 12-month visit between the TRT and control groups were significantly different in BMD (5.0?±?5.0 vs. 3.0?±?3.2; p?=?.0434) and in adiponectin value (?0.90?±?3.33 vs. 0.10?±?2.04; p?=?.0192). There were no significant changes in other parameters.

Conclusions: TRT for 12 months could improve BMD with a decrease in adiponectin levels among hypogonadal men with osteopenia/osteoporosis.