基于模糊CMAC神经网络的医学舌苔图像检索

笔者提出了一种基于模糊CMAC神经网络的医学舌苔图像检索方法。该法利用CMAC网络,实现彩色图像直方图的模糊相关求和,并在此过程中自动调整加权算法中特征色的加权因子,使舌苔图像的检索能针对几大类标准进行,提高了检索效率。实验结果表明,与过去根据经验设定参数的方法相比,本法具有高效、准确,对阴影、反光现象不敏感等特点。     

中药骨碎补提取物质量标准研究

目的研究中药骨碎补提取物的质量控制方法。，方法通过薄层色谱（TLC）法和高效液相色谱（HPLC）法对骨碎补提取物进行质量控制。结果骨碎补提取物中柚皮苷线性范围为0．18～0、89μg（r=0、9999），平均加样回收率为98、13％，RSD为1．85％（n：6）。结论TLC和HPLC两法合用，可定性、定量控制骨碎补中柚皮苷的含量，准确度高，重现性好，操作便捷。     

化学性危害限量标准中危险性评估技术的应用

目的探讨危险性评估技术在化学性危害的危险性评估中的合理应用,为进一步制定有关限量标准提供科学依据。方法结合国内外危险性评估技术的应用,按照危险性评估的框架对不同种类的化学性危害的危险性评估技术进行分析。结果从危害的识别、危害特征的描述、暴露量评估、危险性特征的描述四个方面系统地论述了不同类别的化学性危害的危险性评估技术的选择与应用。结论危险性评估技术已经在世界范围内得到广泛认可,在实际工作中针对特定的化学危害采用适宜的评估技术是为食品安全决策提供科学依据的基础和保障。     

A Prospective Comparative Study of the Aetiology of Cerebral Palsy and Epilepsy in a One-Year Birth Cohort from Northern Finland

ABSTRACT. The one-year birth cohort from Northern Finland comprises 12058 children, representing 96% of all live births in 1966 in the two northernmost provinces of Finland, Oulu and Lapland. Only 14 children, 1.2 per thousand, were lost during the follow-up to 14 years of age, in which data were collected prospectively on development, mortality and morbidity using questionnaires and registers. When all 47 children with cerebral palsy fulfilling the criteria of the Little Club of London (1959) were included, a prenatal risk factor was detected in 13 infants (27.7%) and a perinatal one in 25 children (53.2%), whereas 9 children (19.1%) represented an untraceable form of this disorder. There were 208 children with epilepsy, among which 18 (8.7%) had a prenatal risk factor, 38 (18.2%) a perinatal one, 33 (15.9%) a postnatal one, and 119 (57.2%) no identifiable risk factor. Among the 11320 healthy children in the cohort alive at 14 years of age, there were 992 (8.8%) with risk factors for cerebral palsy and epilepsy. The relative risk attached to these aetiological factors was lower for epilepsy than for cerebral palsy.     

Electrocardiographic Standard for the Diagnosis of Right Ventricular Hypertrophy in Complete Right Bundle Branch Block

It is generally considered that in complete right bundle branch block, the electrocardiographic standard for the diagnosis of right ventricular hypertrophy is not applicable. According to Cohen's criteria, right ventricular overload exists if thallium-201 myocardial perfusion demonstrates the right ventricular wall, and in this light we attempted to reassess the validity of the electrocardiographic standard for right ventricular hypertrophy. Twenty-three children with complete right bundle branch block (abbreviated as CRBBB) were evaluated. The agreement and disagreement ratios of the electrocardiographic standard with Cohen's criteria was 20/23 and 3/23 respectively. Even in patients without intracardiac anomalies, right ventricular overload was suspected by Cohen's criteria. The electrocardiographic standard was in agreement with Cohen's criteria in most of these patients.     

医疗器械行业的重要国际标准《ISO/DIS 13485质量体系--医疗器械--用于法规的体系要求》

介绍了《ISO13485:1996质量体系-医疗器械-ISO 9001:1994应用的专门要求》修订版的国际标准草案（DIS）对其主要修改内容、基本用途、主要指导思想以及和ISO9001:2000的关系,作了初步的说明和分析。虽然正式标准将于明年发布,但由于它已进入批准阶段,其基本框架和主要要求已经确定,因此及时跟踪标准的动向是十分重要的。     

Estimating risk and rate levels,ratios and differences in case-control studies

Classic (or 'cumulative') case-control sampling designs do not admit inferences about quantities of interest other than risk ratios, and then only by making the rare events assumption. Probabilities, risk differences and other quantities cannot be computed without knowledge of the population incidence fraction. Similarly, density (or 'risk set') case-control sampling designs do not allow inferences about quantities other than the rate ratio. Rates, rate differences, cumulative rates, risks, and other quantities cannot be estimated unless auxiliary information about the underlying cohort such as the number of controls in each full risk set is available. Most scholars who have considered the issue recommend reporting more than just risk and rate ratios, but auxiliary population information needed to do this is not usually available. We address this problem by developing methods that allow valid inferences about all relevant quantities of interest from either type of case-control study when completely ignorant of or only partially knowledgeable about relevant auxiliary population information.     

Cigarette smoking and subsequent risk of lung cancer by histologic type in middle-aged Japanese men and women: the JPHC study

In order to update the findings of relative risk associated with cigarette smoking for lung cancer by histologic type in Japan, the data from a population-based cohort study of 91,738 men and women were analyzed. During 1990-1999, 422 lung cancer incident cases were identified. The relative risk for all incident cases associated with current smokers versus non-smokers was 4.5 [95% confidence interval (CI): 3.0-6.8] and 4.2 (95% CI: 2.4-7.2), for men and women, respectively. When divided by histologic type, relative risk for squamous cell carcinoma and small cell carcinoma was 12.7 (95% CI: 4.7-34.7) and 17.5 (95% CI: 4.9-62.1), while for adenocarcinoma it was 2.8 (95% CI: 1.6-4.9) and 2.0 (95% CI: 0.8-5.0) for men and women, respectively. We confirmed that the lung cancer risk in men rose with increasing cigarette smoking, especially the duration of smoking among current smokers and decreased after the cessation of smoking among former smokers. Unlike the US or European countries, the relative risk did not increase in this updated study, compared with previous studies in 1960s to 1990s in Japan either for all incident cases or for specific histologic types and the magnitude of relative risks was substantially lower than that observed in the US or European countries, especially for adenocarcinoma.     

Up-front randomization and common standard arm: a proposal for comparing AML treatment strategies between different studies

Most multicenter randomized AML studies use randomizations of patients early or later in complete remission which necessarily occur with exclusions and positive selection of patients included. Since the exclusion criterias are regimen related and do not follow common standards, incomparabilities between treatment results across different studies are produced by these late randomizations. In order to overcome this problem, we here propose a cooperation of studies on the basis of a general up-front randomization with attribution of 10% patients from each study to a common standard arm. A validation of complete treatment strategies according to intent-to-treat against the standard arm and thus also across the studies is provided by this inter-group model which may contribute to accelerate the therapeutic progress in AML.     

Structure-activity relationships for selected fragrance allergens

Fragrance substances represent a very diverse group of chemicals, a proportion of them providing not only desirable aroma characteristics, but also being associated with adverse effects, notably the ability to cause allergic reactions in the skin. However, efforts to find substitute materials are hampered by the need to undertake animal testing to evaluate both the presence and the degree of skin sensitization hazard. One potential route to avoid such testing is to understand the relationships between chemical structure and skin sensitization. In the present work we have evaluated two groups of fragrance chemicals, saturated aldehydes (aryl substituted and aliphatic aldehydes) and alpha,beta-unsaturated aldehydes. Data on their skin sensitization potency defined using the local lymph node assay has been evaluated in relation to their physicochemical properties. The initial outcome has been consistent with the concept that alpha,beta-unsaturated aldehydes react largely via Michael addition, whilst the group of saturated aldehydes form Schiff bases with proteins. Simple models of chemical reactivity based on these mechanisms suggest that it may be possible to predict allergenic potency. Accordingly, the evaluation of an additional group of similar aldehydes is now underway to assess the robustness of these models, with some emphasis being based on ensuring a wider spread of chemical reactivity.