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61.
We investigated interrelationships among stimulus classes established in matching-to-sample and sequence-production tasks. The analysis focused on the matching and sequencing of quantities, numerals, and arbitrary forms in two individuals with mental retardation. The basic protocol involved: (a) establishing both matching and sequencing performances with some stimuli, (b) training sequencing with a new set of stimuli and assessing whether new matching performances emerged, and (c) training matching with a new set of stimuli and assessing whether new sequencing emerged. The results showed that sequence training did not readily lead to new matching performances, unlike prior research with college students. In contrast, training in matching to sample yielded emergent sequence production; these data support prior studies involving children and adults without developmental disabilities. The results extend prior stimulus class research and suggest an important role for stimulus control processes in the production of generative numeric performances.  相似文献   
62.
Mutations in the hepatocyte nuclear factor-1alpha (HNF-1alpha) gene are the cause of maturity-onset diabetes of the young type 3 (MODY3), which is characterised by a severe impairment of insulin secretion and an early onset of the disease. Also at onset of diabetes some MODY patients show similar clinical symptoms and signs as patients with Type I (insulin-dependent) diabetes mellitus. The objective of this study was to estimate the prevalence of MODY3 patients misclassified as Type I diabetic patients. From a large population-based sample of unrelated Danish Caucasian Type I diabetic patients with an affected first degree relative, 39 patients (6.7%) who did not carry any high-risk HLA-haplotypes, i.e. DR3 or DR4 or both were examined by single-strand conformational polymorphism scanning and direct sequencing of the coding region and the minimal promoter of the HNF-1alpha gene. Four of the 39 Type I diabetic patients (10%) were identified as carrying mutations in the HNF-1alpha gene. One patient carried a missense mutation (Glu48Lys) in exon 1, two patients carried a missense mutation (Cys241Gly) in exon 4 and one patient carried a frameshift mutation (Pro291fsdelA) in exon 4. The mutations were all identified in heterozygous form, segregated with diabetes, and were not identified in 84 unrelated, healthy subjects. Furthermore, family history in three of the four families showed diabetes in four consecutive generations, suggestive of an autosomal dominant inheritance. In conclusion, about 10% of Danish diabetic patients without a high-risk HLA-haplotype, originally classified as having Type I diabetes could have diabetes caused by mutations in the HNF-1alpha gene. Clinical awareness of family history of diabetes and mode of inheritance might help to identify and reclassify these diabetic subjects as MODY3 patients.  相似文献   
63.
64.
GY Han  GQ Shi  LT Qu  JY Yuan  FE Chen  PY Wu 《Polymer International》2004,53(10):1554-1560
N‐Substituted pyrrole derivatives with chiral side groups have been synthesized and electrochemically polymerized in acetonitrile containing tetrabutylammonium perchlorate (TBAClO4) and (S)‐(+)‐camphor‐10‐sulfonic acid ((S)‐(+)‐CSA) or (R)‐(?)‐camphor‐10‐sulfonic acid ((R)‐(?)‐CSA). The resulting N‐substituted polypyrrole films were characterized by cyclic voltammetry, infrared, Raman and X‐ray photoelectron (XPS) spectroscopies. XPS results demonstrated that the as‐grown polymer films are preferably doped by CSA anions when the monomer and the CSA anion have the same optical rotation dispersion (ORD). Furthermore, the conductivities of the polymers synthesized in the media containing CSA with the same ORD of the corresponding monomers were measured to be about 2–10 times higher than those of polymers obtained from electrolytes without CSA. Copyright © 2004 Society of Chemical Industry  相似文献   
65.
A 33 year old man with recurrent respiratory tract infections was admitted to surgery ward. During esophagoscopy and bronchoscopy--esophago-tracheal fistula was found. Diagnosis was confirmed by radiologic examination of esophagus. Surgical treatment was performed with good result.  相似文献   
66.
BACKGROUND: Breast cancer is a major cause of morbidity and mortality in the United States (U.S.) and Missouri. In 1992, 3,915 new breast cancer cases were diagnosed and in 1995, 1,006 deaths from breast cancer were reported in Missouri. Although breast cancer incidence has increased in Missouri in the past 20 years, there are indications that early detection has also increased during the same period. Knowledge about which segments of the population have experienced the greatest increase in mammography screening rates helps in planning and implementation of breast cancer control programs at the state level. OBJECTIVES: Examine the prevalence and trends of lifetime mammography and 2-year mammography compliance in Missouri by age, race, and education from 1987 to 1995 and make predictions for the years 2000 and 2010. METHODS: We used data from the Missouri Behavioral Risk Factor Surveillance System (BRFSS), 1987 to 1995, to estimate the prevalence of ever having had a mammogram and compliance with mammography screening guidelines within two years by race, age, and education status among Missouri women over age 18. Using linear models, we regressed breast cancer screening prevalence estimates on time to obtain trends and predictions. RESULTS: Overall, African-American women were more likely to have had a lifetime mammogram than white women. However, we found a steady increase in the prevalence of ever having had a mammogram for all groups of women defined by age and education status, except among African Americans. Increase in the prevalence of ever having had a mammogram was much higher in women age 50 and older and slightly higher among women with a high school education or less. The average prevalence of 2-year mammography screening compliance was about 60% for all groups, a rate which did not significantly change between 1987 and 1995. By the year 2000, white women will have mammography rates equal to or higher than African-American women, and the majority of all women age 50 and older (98.3% to 100%) will have had a lifetime mammogram. CONCLUSION: Missouri target populations are predicted to attain Year 2000 National Health Objectives concerning lifetime mammography. Current efforts should be continued in order to maintain levels of mammography, particularly among African-American women.  相似文献   
67.
Transgenic insect technology will provide opportunities to explore the basic biology of a broad range of insect species in ways that will prove insightful and important. It is also a technology that will provide opportunities to manipulate the genotypes of insects of practical significance to the health and welfare of humans. The Hermes transposable element from the housefly, Musca domestica, is a short inverted repeat-type element related to hobo from Drosophila melanogaster, Ac from Zea mays, and Tam3 from Antirrhinum majus. It has potential to become a versatile and efficient broad host-range insect transformation vector. The ability of Hermes to transpose when introduced into five species of diptera from four divergent families was tested using an in vivo, interplasmid transpositional recombination assay. Hermes was capable of transposing in all species tested, demonstrating that Hermes has a broad host-range. In addition, the rates of transposition were sufficiently high in all species tested to suggest that Hermes will be an efficient gene transfer vector in a wide range of insect species. The Hermes element also revealed a pattern of integration into the target substrate that permitted factors determining integration site selection to be identified. Primary nucleotide sequence of the integration site played a role as did proximity to preferred integration sites and the nucleosomal organization of the target.  相似文献   
68.
Some smokers are more sensitive than others to the subjective effects of cigarettes, especially the first cigarette of the day. This report explored self-reported subjective effects to the first cigarette of the day and examined the extent to which heaviness of smoking and years smoking are associated with subjective effects. In 3 independent samples (ns?=?254, 116, 86), self-reports of light-headedness from the first cigarette of the day decreased with increasing heaviness of smoking and increasing number of years smoking, suggesting that differences in responses were due to differences in chronic tolerance. Because measures of the subjective effects of drugs are useful in the study of drug response variability, this self-report item on light-headedness should be included in further research on individual differences in the subjective effects of cigarette smoking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
69.
One hundred eleven (58%) of 191 adolescent inpatients previously admitted to the emergency wards at the Child and Adolescent Psychiatric Clinics in the cities of Uppsala and G?teborg participated in a 2-4 year follow-up evaluation. The prevalence, incidence, and stability of depressive symptoms, suicidal ideation, and suicide attempts among the adolescents, and predictors of follow-up functioning were examined. Although a majority of the patients substantially reduced their depressive symptoms over the 2-4 year period, a smaller group (13%), mainly girls (94%), continued reporting high symptom levels at follow-up, and one out of five adolescents had moderate-severe levels of suicidal ideation. The accumulated frequency of suicide attempts among the patients shortly prior to hospitalization and during the follow-up was 59% including two patients who committed suicide. Significant predictors of depressive symptom severity at follow-up were depressive symptom scores and V-diagnoses at inpatient assessment. Previous suicide attempts before hospitalization, high levels of self-reported depressive symptoms and nonintact family status at inpatient assessment predicted suicide attempts during the follow-up period. The high prevalence of attempted and completed suicide in this clinical group underscores the importance of developing effective treatments for suicidal adolescents.  相似文献   
70.
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