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111.
BACKGROUND: Digital computer analysis of dermatoscopical images has been reported to facilitate the differential diagnosis of pigmented skin lesions in recent years. OBJECTIVE: The aim of our study was to perform digital computer analysis of a set of different melanocytic lesions and compare the objective results. METHODS: The set of 260 melanocytic lesions (150 excised difficult cases (46 melanomas, 47 atypical nevi, 57 common nevi and 110 unexcised common nevi) was automatically analysed by the digital dermatoscopical system microDERM. We searched for differences in asymmetry, size, compactness and colour distribution. Perimeter/area ratio was calculated. RESULTS: The perimeter/area ratio was detected as the most important criterion for differentiation between malignant and benign melanocytic lesions (sensitivity 91.3% and specificity 90.7% for malignant melanomas vs. all benign nevi; sensitivity 91.3% and specificity 80.8% for melanomas vs. clinically atypical nevi). Differences in size of the lesion, shape and asymmetry of colour were found and statistically verified. Using step-wise logistic regression the formula for calculation of probability of malignant nature of every analysed lesion was constructed. CONCLUSION: The perimeter/area ratio is a simple parameter for the differential diagnosis of melanocytic skin lesions.  相似文献   
112.
Analytical validation of a competitive direct SUNQuik ELISA with a reference High Performance Liquid Chromatography (HPLC) method and other methods including a minicolumn method and the VICAM Aflatest® system for aflatoxin in peanuts was conducted. Both the ELISA and the VICAM Aflatest® system, using the same peanut extracts were analytically comparable with the HPLC method (R=0.998, p<0.000). The minicolumn method was also found to be acceptable as a low cost rapid semi-quantitative test. Despite the large variation in sampling, the correlation between the SUNQuik ELISA and HPLC using the different peanut sub-samples was considered acceptable over the range of 0–1200 µg kg?1 (R=0.938). No false negatives were found using the SUNQuik ELISA and false positives were either nil or negligible in all the studies conducted. The repeatability of the SUNQuik ELISA run on the same day was good with only±10% deviation. The reproducibility of the SUNQuik ELISA between days was also acceptable, but with a higher deviation. Applying the SUNQuik ELISA for aflatoxin surveys of peanuts in Indonesia proved that the method can deliver high quality, cost- and time-effective analysis with very little establishment capital and maintenance.  相似文献   
113.
Methylation is an important pathway in the biotransformation of many drugs, neurotransmitters, and xenobiotic compounds. Histamine N-methyltransferase (HNMT) catalyzes the Nτ-methylation of histamine and structurally related compounds. Measurement of HNMT activity in the RBC makes it possible to access variation in the enzyme activity that may reflect differences in less accessible tissues such as brain. Previously reported high family correlations for RBC HNMT activity suggested that genetic inheritance plays a major role in the regulation of variation in this enzyme. In the present study we completed complex segregation analyses of RBC HNMT activity of 241 individuals in 51 nuclear families that were randomly ascertained through children in the Rochester, Minnesota public school system in order to characterize the mode of inheritance of this important enzyme. We found evidence for major gene influence on the regulation of RBC HNMT activity. Both transformed and untransformed data support the presence of Mendelian major gene segregation, but the gene frequency differences do not indicate a direct correspondence between genotypes inferred from the two sets of analyses. Analyses of the skewed untransformed data indicated the presence of a relatively rare (Q = 0.121) additive major gene for high activity, with the three overlapping genotype distributions representing 77, 21, and 2 % of individuals. Analyses of the normalized transformed data indicated the presence of a common (Q = 0.71) additive major gene for high activity, with the three overlapping genotype distributions accounting for 9, 41, and 50 % of individuals. The analyses of transformed data give the best fit as well as the most parsimonious Mendelian major gene model. However, we cannot rule out the possibility of multiple alleles, and analyses of untransformed data provide some support for a third allele. Molecular studies will be needed to validate and characterize the alleles that regulate RBC HNMT activity levels in humans. © 1993 Wiley-Liss. Inc.  相似文献   
114.
AIM To clone novel gastric cancer-associated genes and investigate their roles in gastric cancer occurrence.METHODS A method called differential display was used which allows the identification of differentially expressed genes by using PAGE to display PCR-amplified cDNA fragments between gastric cancer cells and normal gastric mucosa cells. These fragments were cloned into plasmid vector pUC18. Homology analysis was made after sequencing these fragments.RESULTS Two novel genes were identified compared with sequences from GenBank. One was registered with the AD number AF 051783. In situ hybridization showed that these two novel genes expressed specifically in gastric cancer tissues.CONCLUSION The two novel genes obtained by differential display were confirmed to be gastric cancer-associated genes using in situ hybridization.  相似文献   
115.
Summary 15 normal volunteers were treated over three weeks with haloperidol (HAL) and in the third week additionally with biperidene (BIP). The order of the EEG spectra at different topographical locations and in different frequency bands during a movement task was analyzed using uncertainty analysis (UA), a multivariate analysis technique based on informationtheoretical methods. Different patterns of drug-induced changes were found. HAL decreases the theta and alpha band order at the fronto-central lateral areas but increases it at the fronto-central midline in the theta band and at the parietal areas in the alpha band. With the exception of the fronto-central midline locations, BIP more or less counterbalances the effect of HAL. Volunteers felt unwell and had motor disturbances during HAL and felt well again during HAL + BIP. Reaction time values were increased during HAL and normalized during HAL + BIP.  相似文献   
116.
Summary. During the course of sterility treatment semenograms of 271 IVF and 316 insemination patients were carried out by two automated semen analysers. The parameters of these analyses were correlated to pregnancies resulting from the treatment. Semen samples were analysed in the ejaculate and after swim-up preparation. In addition, the swim-up suspension of IVF patients was measured again 18 h after sperm preparation. Patients were divided into three groups: (1) couples who achieved a pregnancy, (2) couples who did not achieve a pregnancy, and (3) IVF patients with no fertilization of the oocytes. Because of large standard deviations in the quality of ejaculates, the results in the IVF group show no significant differences in the semen parameters of husbands of pregnant and non-pregnant women. In contrast husbands of women with no fertilization have a significantly lower sperm motility. After swim-up preparation these differences no longer occur. A further measurement, taken 18 h later, reveals that there are no differences in the sperm parameters between the pregnant and non-pregnant group. However, the semen quality in the group with no fertilization is significantly reduced. The results of the insemination patients are similar to those of the IVF group. Thus, the results from automated sperm analysers cannot replace either the microscopic or biochemical analysis of an ejaculate and, moreover, cannot be used as prognosis for the fertilization capacity of sperms or a following pregnancy.  相似文献   
117.
This study is a predictor analysis of the screening procedure followed by a psychiatric service for a period of 1 year preceding and a period of 1 year following the introduction of community psychiatry. Throughout this period, the psychiatric service consisted of a local service within the catchment area and a central service at a psychiatric hospital outside the area. At the time of the reorganization, the responsibility for the psychiatric service was transferred from the public health authorities to the social services. Before the reorganization, screenings were conducted on the basis of referral papers or simply as a result of telephone communication. After the reorganization, the screening procedure was intensified by means of a pre-examination. One aim of the reorganization was to ensure that the severely mentally ill take priority over patients characterized predominantly by social strain. Patients with manic-depressive psychosis and other psychoses showed a significantly increased probability of being accepted for treatment, whereas those with schizophrenia showed no significant increase, irrespective of the service reorganization. Similarly, manic-depressive psychosis and other psychoses (not schizophrenia) were significant predictors of hospitalization at the mental hospital outside the catchment area as well as hospitalization in the local facilities, irrespective of the service reorganization. Indicators of social strain were not given higher priority following the service reorganization.  相似文献   
118.
通过对200例老年人心律失常的病因分析,明确了老年人心律失常的发生有其形态学基础,再加上疾病综合作用所致。其中缺血性心脏病占首位,再依次为高血压病、肺心病、脑血管病、糖尿病、颈椎病。同时患有两种以上疾病的心律失常发生率明显增高。另外还对心功能及烟酒对心律失常的影响进行了初步探讨,结果显示心功能异常及吸烟与心律失常的发生呈正相关,饮酒与心律失常的发生呈负相关。  相似文献   
119.
Prognosis of acute renal failure in children: a multivariate analysis   总被引:5,自引:5,他引:0  
Various factors were analyzed in 80 consecutive children under 16 years who had acute renal failure (ARF), for various prognostic factors. Overall mortality was 42.5%, with significantly higher levels seen in hemolytic uremic syndrome (68%, P <0.05) and associated with cardiac surgery (90.9%, P <0.01). Anuria (67.6% vs. 43.5%, P <0.05), need for dialysis (85.3% vs. 56.5%, P <0.05), neurological complications (50% vs. 6.3%, P <0.01), and respiratory complications (35.2% vs. 2.1%, P <0.01) were significantly higher in nonsurvivors than survivors. Multiple regression analysis showed the presence of neurological and respiratory complications to be poor prognostic factors. Received May 2, 1995; received in revised form August 28, 1996; accepted September 13, 1996  相似文献   
120.
癌变的早期诊断对提高疗效具有特殊意义,为了寻求简捷,高效,超前,可靠的诊断方法,实验以DMBA(二甲基苯并蒽)诱导的金地鼠颊囊致癌模型为对象,以PCNA(增殖细胞核抗原)BrdV(溴脱氧尿嘧啶)等免疫组化技术为手段;以光镜观察诊断为对照,对三种观察结果进行相关分析,发现三者间有高度显著的相关性,证实了免疫组化方法在癌变诊断中有一定的参考价值,实验还发现PCNA和BrdU检测结果比较每天敏感,简捷,  相似文献   
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