The UK Diabetes Research Network--an opportunity and a challenge.

The Department of Health has funded a national diabetes network to support clinical research. The network will facilitate recruitment into clinical trials and has been widely welcomed by clinicians. However, if the network is to reach its full potential, all those involved will need to advocate a change in attitude towards clinical trials and research, encouraging participation and contribution of data. Clinicians need to be willing to take a proactive view about research studies, and to encourage patients to adopt a positive and altruistic attitude towards trial participation. The future of trials and other important clinical research in the UK may depend on it.     

安氏Ⅲ类错畸形病因的logistic分析

目的研究引起安氏Ⅲ类错牙合畸形的病因。方法对50例安氏Ⅲ类错牙合患者和50例正常牙合人作病因问卷调查,将结果用logistic法分析,提取有效病因。结果共有慢性扁桃体炎、遗传因素、咬上唇3项病因进入方程。结论按贡献大小,长期慢性扁桃体炎、经常咬上唇和遗传因素是导致安氏Ⅲ类错牙合畸形的危险因素。     

Evaluating risk factors associated with severe hypoglycaemia in epidemiology studies—what method should we use?

AIMS: To determine the most appropriate regression models to use when assessing risk factors for severe hypoglycaemia and to investigate the impact of model misspecification and its clinical implications. METHODS: A total of 1229 children with Type 1 diabetes (mean age 11.7 years sd 4.1), of which 605 (49.2%) were males, were studied. Prospective assessment of severe hypoglycaemia (an event leading to loss of consciousness or seizure) was made over the 9-year period, 1992-2001. Patients were seen every 3 months and episodes of hypoglycaemia along with clinical data were recorded. Over 70% of children never experienced a severe hypoglycaemic event. Data were analysed using the Poisson regression, negative binomial, zero-inflated Poisson (ZIP) and zero-inflated negative binomial (ZINB) models. The over-dispersion and likelihood ratio statistics were calculated and the analytical methods compared. RESULTS: The Poisson regression model did not fit the data well. The negative binomial and the zero inflated Poisson and negative binomial models fitted the data better than Poisson. CONCLUSIONS: The commonly used Poisson regression models to analyse hypoglycaemia epidemiology may lead to biased parameter estimates and incorrect determination of risk factors for hypoglycaemia. We recommend the use of the negative binomial or zero inflated models to examine any risk factors associated with severe hypoglycaemia. Careful consideration must be given to the interpretation of hypoglycaemia surveys and their analysis.     

Neuropathology of schizophrenia: A mini review

The neuropathology of schizophrenia remains obscure despite the fact that many neuropathologists have investigated this area for over 100 years. While remarkable progress has been made in the neuropathological study of neurodegenerative diseases including Alzheimer's disease, progress in studying the neuropathological entity of schizophrenia has not kept pace; the phrase “schizophrenia is the graveyard of neuropathologists” has been stated in the field. Since the 1980s, the morphological or functional abnormalities in the brains of schizophrenia patients have been reported by means of CT or MRI and with advanced functional brain image technology such as positron emission tomography or single photon emission computed tomography. Results from such imaging studies have led to neuropathological examination of the post mortem brains of schizophrenia patients being undertaken again. These neuroimaging studies have influenced the neuropathological investigation of the schizophrenic brain. Not only the classical microscopic observation of neuropathology, but also measurement and statistical analysis using computer imaging software or using immunohistological techniques has been performed. Based on the neuropathological studies of schizophrenia over the last 20 years, it is clear that schizophrenia is not a pure functional disease without organic factors. Reports of neuropathological abnormalities in the post mortem schizophrenic brain indicated they were found in almost all areas of the brain, but there are more reports describing the temporal lobe and frontal lobe compared to those describing other areas of the brain. These observed neuropathological abnormalities are explained rationally by the hypothesis of a neurodevelopmental disorder in this disease. In recent molecular biology studies, several putative candidate genes were reported, and some of these genes might have the function of neurodevelopment or making neuronal networks. It is important to consider together these findings with morphometric studies in neuropathological observation, neuroimaging studies and genome studies to pursue the etiology of schizophrenia from various perspectives.     

一种新的正交参数选优法及其在非线性回归分析中的应用

非线性回归分析是工程中经常采用的一种用来估计数学模型参数的方法，该方法能否顺利运用与参数初始值的选择有极大关系。本研究提出一种新的正交参数选优法——阻尼正交表法，它不仅可以保证非线性回归分析算法的顺利收敛，而且能够显著提高后者的收敛速度，进而极大改善非线性回归分析算法的应用性能。本研究的数值试验及心肌造影超声心动图定量分析应用实例表明，作为对传统正交参数选优法的一种改进，阻尼正交表法在科学与工程计算或信号与信息处理领域有着很好的应用前景。     

基于无线网络及条形码技术的图书排架、定位系统

利用无线网络与条形码技术,建立起图书排架、定位系统,可实现图书排架和图书的准确定位.该系统可有效地解决传统管理方法易产生的乱架和死书问题,提高图书借阅效率并降低管理人员的工作强度.     

药物的定量构效关系的方法学研究——改进的逐步回归算法

在定量的构效关系研究中,多重回归分析选人的参数,多是用穷举所有方程实现的。本文提出一种改进的逐步回归算法,计算实例表明,是个行之有效的方法。     

Organization and physiology of thesubstantia nigra

Summary A comprehensive review of the literature on the anatomy, electrophysiology and pharmacology of thesubstantia nigra is presented. A diagram is developed taking into account the interneuronal interactions of neurotransmitters and receptors that control firing rates and neurotransmitter releases. The central features of the diagram are a positive dopaminergic feedforward process and a positive feedback mechanism mediated by extrasynaptic substance P diffusing from striatal terminals to dopaminergic dendrites of thezona compacta neurons. This loop can enhance the transmission of information from thestriatum through thepars reticulata output neurons. The loop is controlled at the level of zona compacta neurons by a negative feedback supported by the dendritic release of dopamine and boosted by pedunculopontine activation mediated by muscarinic receptors. The output of the loop is controlled by two negative feedforward processes, both involving GABAergic striatonigral afferents. Application of the model to pharmacological studies of diverse behaviors including seizures, turning, and conditioned behaviors reveals unforseen relationships and may offer insights into, and directions for, further analysis of the mechanisms and functions involved.     

BP神经网络及其在药学研究中的应用

BP神经网络是目前应用最广泛的人工神经网络模型，本文详细阐述了BP神经网络的原理和特点，并论述了其在药学研究中的应用。