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At least 829 records · Page 46Linked to original sources
PubMed1985

Physical, psychological, social, and lifestyle differences among adolescents classified according to cigarette smoking intention status.

This study was conducted to determine the extent to which multiple physical, psychological, social, and lifestyle measures differ among high school males classified according to cigarette smoking intention status including nonintenders, mild intenders, and strong intenders. The Physical Performance Test for California, to measure six traits of physical fitness and Cattell's 16PF Questionnaire to assess manifold dimensions of personality were administered to 386 high school males. Self-concept was measured by Rosenberg's Self-esteem Scale and body build was assessed using Tucker's Perceived Somatotype Scale and the Body Mass Index. Data relative to marital status of parents, exercise experience, church attendance, participation in athletics, alcohol drinking habits, television viewing behavior, intention to attend college, dating behavior, as well as general demographic information and intention to smoke cigarettes were assessed by a written questionnaire. Results indicated that nonintenders were significantly more self-confident, intelligent, emotionally stable, moralistic, conservative, group oriented, self-controlled, relaxed, and more likely to respond in a socially desirable manner than were strong intenders. Nonintenders reported less dating, less television viewing, less alcohol consumption, and perceived themselves as and were determined to be less obese than strong intenders. Nonintenders also reported greater intentions to attend college, greater varsity athletic participation, were more likely to be residing with their natural mothers, and were more physically fit than were strong intenders. Possible health education and youth smoking prevention strategies are discussed.

Adolescent↗
PubMed2001

[Clinical analysis of patients with community-acquired pneumonia requiring hospitalization classified by age group].

We classified 1017 patients with community-acquired pneumonia requiring hospitalization experienced in Kawasaki Medical School Kawasaki Hospital during the past 15 years into five age groups (< or = 54 years old, 55-64 years old, 65-74 years old, 75-84 years old, > or = 85 years old). With particular emphasis on the elderly patients, we then compared the clinical and microbiological findings in the five groups. The results were as follows; (1) Half of patients in the over 85 years old group were bed-ridden. (2) The proportion receiving antibiotics before hospitalization decreased with age. (3) There were striking atypical pneumonic symptoms, such as dyspnea and consciousness disturbance in the two age groups over 75 years old. (4) Hypotension (shock) increased with age. (5) Markers of nutritional conditions, such as serum protein, albumin, cholinesterase, and hypoxia remarkably increased in the two age groups over 75 years old. (6) There were no significant differences in the isolation rate of etiological microorganisms. (7) The number of polymicrobial agents in the < or = 54 years old group was lower than that in the other age groups. (8) Mycoplasma pneumoniae was most significantly higher in < or = 54 years old group, Haemophilus influenzae in patients 55-64 years old, and Streptococcus pneumoniae in both 65-74 and 75-84 years old groups. (9) The isolation rate of MSSA, gram-negative bacilli such as Klebsiella pneumoniae, Pseudomonas aeruginosa, respiratory viruses increased with age. (10) The amount of sepsis increased with age. (11) The prognosis was poor in the two groups over 75 years old because the mortality rate (over 10%) was higher that for the other age groups.

Age Distribution↗
PubMed2002

Development and evaluation of a case-based reasoning classifier for prediction of breast biopsy outcome with BI-RADS lexicon.

Approximately 70-85% of breast biopsies are performed on benign lesions. To reduce this high number of biopsies performed on benign lesions, a case-based reasoning (CBR) classifier was developed to predict biopsy results from BI-RADS findings. We used 1433 (931 benign) biopsy-proven mammographic cases. CBR similarity was defined using either the Hamming or Euclidean distance measure over case features. Ten features represented each case: calcification distribution, calcification morphology, calcification number, mass margin, mass shape, mass density, mass size, associated findings, special cases, and age. Performance was evaluated using Round Robin sampling, Receiver Operating Characteristic (ROC) analysis, and bootstrap. To determine the most influential features for the CBR, an exhaustive feature search was performed over all possible feature combinations (1022) and similarity thresholds. Influential features were defined as the most frequently occurring features in the feature subsets with the highest partial ROC areas (0.90AUC). For CBR with Hamming distance, the most influential features were found to be mass margin, calcification morphology, age, calcification distribution, calcification number, and mass shape, resulting in an 0.90AUC of 0.33. At 95% sensitivity, the Hamming CBR would spare from biopsy 34% of the benign lesions. At 98% sensitivity, the Hamming CBR would spare 27% benign lesions. For the CBR with Euclidean distance, the most influential feature subset consisted of mass margin, calcification morphology, age, mass density, and associated findings, resulting in 0.90AUC of 0.37. At 95% sensitivity, the Euclidean CBR would spare from biopsy 41% benign lesions. At 98% sensitivity, the Euclidean CBR would spare 27% benign lesions. The profile of cases spared by both distance measures at 98% sensitivity indicates that the CBR is a potentially useful diagnostic tool for the classification of mammographic lesions, by recommending short-term follow-up for likely benign lesions that is in agreement with final biopsy results and mammographer's intuition.

Adult↗
PubMed2001

Linear prediction coding analysis and self-organizing feature map as tools to classify stress calls of domestic pigs (Sus scrofa).

It is assumed that calls may give information about the inner (emotional) state of an animal. Hence, in the last years sound analysis has become an increasingly important tool for the interpretation of the behavior, the health condition, and the well-being of animals. A procedure was developed that allows the characterization, classification, and visualization of the cluster structures of stress calls of domestic pigs (Sus scrofa). Based on the acoustic model of the sound production the extraction of features from calls was performed with linear prediction coding (LPC). A vector-based self-organizing neuronal network was trained with the determined LPC coefficients, resulting in a feature map. The cluster structure of the calls was then visualized with a unified matrix and the neurons were labeled for their input origin. The basic applicability of the procedure was tested by using two examples which were of special interest for a possible evaluation of the normal farming practice. The procedure worked well both in discriminating individual piglets by their scream characteristics and in classifying pig stress calls vs other calls and noise occurring under normal farming conditions.

Acoustics↗
PubMed2006

Using an artificial neural network to classify black-capped chickadee (Poecile atricapillus) call note types.

The "chick-a-dee" call of the black-capped chickadee (Poecile atricapillus) contains four note types, A, B, C, and D that have important functional roles. This provides strong motivation for studying the classification of acoustic components of the call into different note types. In this paper, the spectrograms from a sample of A, B, and C notes (370 in total) were each described as a set of 9 summary features. An artificial neural network was trained to identify note type on the basis of these features, and was able to obtain better than 98% accuracy. An internal analysis of this network revealed a distributed code in which different hidden units generated high activities to different subsets of notes. By combining these different sensitivities, the network could discriminate all three types of notes. The performance of this network was compared to a discriminant analysis of the same data. This analysis also achieved a high level of performance (95%). A comparison between the two approaches revealed some striking similarities, but also some intriguing differences. These results are discussed in terms of two related issues: developing a research tool for note classification, and developing a theory of how birds themselves might classify notes.

Animals↗
PubMed2001

Detection of immunologically significant factors for chronic fatigue syndrome using neural-network classifiers.

Neural-network classifiers were used to detect immunological differences in groups of chronic fatigue syndrome (CFS) patients that heretofore had not shown significant differences from controls. In the past linear methods were unable to detect differences between CFS groups and non-CFS control groups in the nonveteran population. An examination of the cluster structure for 29 immunological factors revealed a complex, nonlinear decision surface. Multilayer neural networks showed an over 16% improvement in an n-fold resampling generalization test on unseen data. A sensitivity analysis of the network found differences between groups that are consistent with the hypothesis that CFS symptoms are a consequence of immune system dysregulation. Corresponding decreases in the CD19(+) B-cell compartment and the CD34(+) hematopoietic progenitor subpopulation were also detected by the neural network, consistent with the T-cell expansion. Of significant interest was the fact that, of all the cytokines evaluated, the only one to be in the final model was interleukin-4 (IL-4). Seeing an increase in IL-4 suggests a shift to a type 2 cytokine pattern. Such a shift has been hypothesized, but until now convincing evidence to support that hypothesis has been lacking.

B-Lymphocytes↗
PubMed1979

Relationship of hemagglutination to other biological properties of serologically classified isolates of Escherichia coli.

The ability of 170 serologically classified strains of Escherichia coli to agglutinate human erythrocytes was examined. Erythrocytes of blood group A were more sensitive indicators of this property than were those of groups B or O. The predominant receptor was shown to be mannose containing; however, an additional receptor was found in two of nine strains studied. Natural mannose-like inhibitors were not found in unconcentrated urine obtained from 12 humans. Isolates from the urine or blood of patients with infections agglutinated erythrocytes significantly more frequently than did isolates from feces. Urine isolates of 10 common serogroups and isolates of less common serogroups did not differ in their ability to agglutinate erythrocytes. Among isolates from the urine of patients with infections, the ability to agglutinate erythrocytes did not correlate with either the serogroup of the strain or the clinical syndrome of the patient. Of the several other biological properties that were examined, only the production of colicins showed a significant association with the ability to agglutinate human erythrocytes.

ABO Blood-Group System↗
PubMed1968

Production of and sensitivity to colicins among serologically classified strains of Escherichia coli.

A significant proportion of 242 serologically classified strains of Escherichia coli of human origin produced colicins (33%) or were inhibited by one or more of six standard colicins (57%). The most common colicins identified were E1, I, and B; colicins B and V had greatest range of activity. Generally, neither the production of, nor sensitivity to, individual colicins was restricted to strains of a single serogroup. The coexistence of strains of one serogroup that were sensitive to the action of a colicin produced by strains of another serogroup was encountered among 2 of 21 fecal specimens containing strains of multiple serogroups. The production of colicins was not a major determinant in the acquistion of, or subsequent changes in, strains of E. coli in the feces of 10 newborn infants.

Bacteriological Techniques↗
PubMed2006

Classifying spa types in complexes improves interpretation of typing results for methicillin-resistant Staphylococcus aureus.

A total of 382 isolates of methicillin-resistant Staphylococcus aureus originating from three Austrian regions and one adjacent Italian region (Vienna, Lower Austria, North Tyrol, and South Tyrol) were typed by DNA sequence analysis of the variable repeat region of the protein A gene (spa typing). The strain collection consisted of arbitrarily chosen isolates originating from clinical specimens taken in the years 2003 to 2005 at 17 hospitals. The most common spa types found were t001 (28.8% of all isolates), t190 (27.0%), t008 (14.1%), and t041 (11.3%). The 42 remaining spa types accounted for <or=2.4% each. The dominating spa types varied between the different regions. As short sequence DNA repeat units are unstable entities, the 46 spa types were classified into seven spa complexes with respect to short sequence repeat unit composition and organization. Such classification into complexes can provide additional information for the hospital epidemiologist, empowering one to differentiate the introduction of a new strain from mere variation of endemic spa types.

Austria↗
PubMed1997

Use of heteroduplex analysis to classify legionellae on the basis of 5S rRNA gene sequences.

Seventeen different species of Legionella, 12 serogroups of Legionella pneumophila, and 2 Legionella-like amoebal pathogens (LLAP1 and Sarcobium lyticum) were examined by heteroduplex analysis of PCR products of the 5S rRNA gene. Eight different banding patterns were identified, indicating that heteroduplex analysis of this gene can be used to classify these bacteria according to base substitutions between species. This classification may have future applications in clinical and epidemiological studies.

Bacterial Typing Techniques↗
PubMed2026

VISTA: a classifier for metagenomic subspecies and community state typing of the vaginal microbiome.

Metagenomic community state types (mgCSTs) capture within-species genetic and functional diversity and community structure of the vaginal microbiome, enabling precise links between microbiome composition, function, and health-related risk. VISTA, the Vaginal Inference of Subspecies and Typing Algorithm, is a two-step classifier that assigns mgCSTs to vaginal metagenomes, providing standardized, scalable classifications.

bioinformatics↗
PubMed1982

Two-year study of the causes of postperinatal deaths classified in terms of preventability.

A detailed pathological and psychosocial study was made of all postperinatal (8 days-2 years) deaths in Sheffield during a 2-year period. The cause of death was classified from the point of view of possible prevention. Of the total of 65 deaths, 35 were unpreventable after the perinatal period, but 9 might have been preventable before birth. Of the 30 other deaths, 20 had evidence of possible treatable disease, and for the majority of these adverse social factors could be identified. Proved non-accidental injury occurred in 2 children and in 3 others there was a high degree of suspicion of 'gentle battering'. Only in 4 children was death unexplained and this apparently represents the local true unexplained cot death rate of 0.16/1000 births.

Child Health Services↗
PubMed2005

Comparison of different definitions to classify remission and sustained remission: 1 year TEMPO results.

OBJECTIVE: To assess methods to calculate achieving and sustaining remission in a double blind randomised trial in patients with RA who received etanercept, methotrexate, or an etanercept/methotrexate combination. METHODS: Remission was defined as DAS <1.6, DAS28 <2.6, and ACR70 response. Sustaining remission was analysed in three ways: (a) analysis of sustained DAS remission, DAS28 remission, or ACR70 response continuously for 6 months; (b) analysis of sustained remission appraised through a continuity rewarded scoring system, which is the weighted sum of all intervals in the study in which patients are in DAS or DAS28 remission; or (c) longitudinal modelling of remission odds using generalised estimating equations. RESULTS: Significantly more patients treated with the etanercept/methotrexate combination reached DAS remission (37%) than those treated with either methotrexate (14%) or etanercept (18%) alone (p<0.01). Results for DAS28 and for the ACR70 response were similar. Agreement between DAS remission and DAS28 remission was good, but agreement between either of these and the ACR70 response was less. Patients in DAS or DAS28 remission had a lower level of disease activity (fewer active joints, lower ESR) than those achieving ACR70 response; the converse was seen using pain VAS. The three methods were comparable for sustainability of remission and showed significant advantage for combination therapy, which increased the number and durability of remission periods. CONCLUSIONS: DAS and DAS28 remission results were similar for assessing achieving and sustaining remission in RA, frequently differing from patients classified as ACR70 responders. The three methods of examining duration of remission produced comparable results.

Adult↗
PubMed1975

Attempt to classify patients with arthritis of the hip suitable for prosthetic replacement, and their femoral heads.

Using clinical, radiological, and morbid anatomical data about patients with arthritis of the hip and their femoral heads resected during total hip replacement, an attempt has been made first, to classify patients and femoral heads by a cluster analysis technique, and secondly and more realistically, to use existing clinical and radiological classification as a basis for seeking discriminating features in the data from the femoral head. Both types of analysis failed to give results, and led to a conclusion that arthritis of the hip is a spectrum of disease. This may not pose problems to the clinician, but it does to the investigator studying the pathogenesis of osteoarthrosis. This problem is briefly discussed.

Arthritis↗
PubMed2006

Classifying undetermined poisoning deaths.

OBJECTIVE: To classify poisoning deaths of undetermined intent as either suicide or unintentional and to estimate the extent of underreported poisoning suicides. METHODS: Based on 2002 statewide death certificate and medical examiner data in Utah, the authors randomly selected one half of undetermined and unintentional poisoning deaths for data abstraction and included all suicides. Bivariate analyses assessed differences in demographics, death characteristics, forensic toxicology results, mental health history, and other potentially contributing factors. Classification and regression tree (CART) analysis used information from unintentional and suicide poisoning deaths to create a classification tree that was applied to undetermined poisoning deaths. RESULTS: The authors analyzed 41 unintentional, 87 suicide, and 84 undetermined poisonings. Undetermined and unintentional decedents were similar in the presence of opiates, physical health problems, and drug abuse. Although none of the undetermined decedents left a suicide note, previous attempt or intent to commit suicide was reported for 11 (13%) of these cases. CART analysis identified suicidal behavior, drug abuse, physical health problems, depressed mood, and age as discriminating between suicide and unintentional poisoning. It is estimated that suicide rates related to poisoning are underreported by approximately 30% and overall suicide rates by 10%. Unintentional poisoning death rates were underreported by 61%. CONCLUSIONS: This study suggests that manner of death determination relies on circumstance dependent variables that may not be consistently captured by medical examiners. Underreporting of suicide rates has important implications in policy development, research funding, and evaluation of prevention programs.

Adult↗
PubMed1993

Nucleolar organiser regions and survival in patients with non-Hodgkin's lymphomas classified by the working formulation.

AIMS: To correlate the numbers of silver staining nuclear organiser regions (AgNORs) in non-Hodgkin's lymphoma classified by the working formulation with survival, the first complete remission, and the length of remission. METHODS: Sixty one patients were included in the study. Paraffin wax sections were stained using silver solution to visualise nucleolar organiser regions. The AgNORs were counted in 150 nuclei of each specimen. Data were examined using the Kruskal-Wallis test, multivariate discriminant analysis, and Cox's regression test. Curves were calculated by the method of Kaplan and Meier. RESULTS: Most patients who were alive had low grade lymphoma (p < 0.01). The first complete remission was obtained more frequently in the low and intermediate grade groups (p < 0.05). The longest survival was found in the low grade group (p < 0.001). The mean number of AgNORs differed significantly in all three groups (p < 0.001). This was also true for area of nuclei (p < 0.001) and length of remission (p < 0.05). In a multivariate analysis the numbers of AgNORs were highly predictive for survival, remission, and the length of remission. CONCLUSIONS: The numbers of AgNORs correlated with survival, remission, and the length of remission in patients with non-Hodgkin's lymphoma.

Adolescent↗
PubMed1988

Are malignant melanoma time trends explained by changes in histopathological criteria for classifying pigmented skin lesions?

The incidence of malignant melanoma in developed countries has been rising rapidly in recent years. Its causes and the reasons for this trend are uncertain. Changes in histopathological criteria for classifying pigmented skin lesions could explain the rising incidence rates. With support from the International Agency for Research on Cancer, this hypothesis is explored but not substantiated for time trends in the South Western Region, United Kingdom.

England↗