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991.
Crimmins EM Alley D Reynolds SL Johnston M Karlamangla A Seeman T 《The journals of gerontology. Series A, Biological sciences and medical sciences》2005,60(11):1409-1413
BACKGROUND: Many studies that show improved health in older adults have relied on subjective measures of health. This article assesses changes in the physiological status of older Americans during the 1990s using biological measures of high-risk for morbidity and mortality. METHODS: Changes in the prevalence of clinically-defined, high risk for 10 biological markers were assessed in respondents age 65 years and older from National Health and Nutrition Examination Surveys (NHANES) III (1988-1994) and IV (1999-2000). RESULTS: Some changes in prevalence of high-risk values of biological markers indicate improved health among older adults in the 1990s: a 6% reduction in the prevalence of high-risk total cholesterol (p <.001) and a 7% reduction in the prevalence of high-risk homocysteine (p <.001). Other changes indicate worsening health: a 9% increase in the prevalence of high-risk systolic blood pressure (p <.01), a 10% increase in obesity (p <.001), and an 8% increase in the prevalence of high-risk C-reactive protein (p <.001). These changes remained significant after adjusting for age, sex, and education. Results of logistic regressions indicate that changes in the frequency of medication usage, medication efficacy, prevalence of chronic disease, and diet explained some of these changes. CONCLUSIONS: Changes in the prevalence of high-risk values of biological markers in the 1990s are mixed. Greater use and effectiveness of lipid-lowering medication has contributed to the reduction in percentage of the population with high-risk lipid levels, and folate supplementation accounted for a decline in the percentage with high-risk homocysteine. However, increases in the percentage with high-risk systolic blood pressure occurred despite an increase in the use of antihypertensive medications, in part because of the limited ability of antihypertensive medications to bring blood pressure below high-risk levels. 相似文献
992.
Seeman TE Huang MH Bretsky P Crimmins E Launer L Guralnik JM 《The journals of gerontology. Series B, Psychological sciences and social sciences》2005,60(2):P74-P83
Longitudinal data from the MacArthur Study of Successful Aging were used to test for interactions between education and apolipoprotein E (APOE) genotype with respect to time trends in cognitive performance. Interactions between education, APOE-e4 status, and time were found for overall cognitive function, and for subscales measuring memory and naming: The presence of the e4 allele was associated with steeper declines in cognition for those with a greater than eighth-grade education. For those with an eighth-grade education or less, time trends did not differ by APOE genotype. A measure of cognitive impairment (i.e., scores of < or = 7 on the Short Portable Mental Status Questionnaire) yielded parallel though weaker evidence for a similar interaction with respect to risk of cognitive impairment. These findings suggest that the presence of at least one e4 allele appears to reduce the protective effects of education for those with at least a ninth-grade education or more, resulting in steeper cognitive declines with age. 相似文献
993.
V Almazán A Pulpón L de Teresa E Catalán L Burgui M Artaza Andrade 《Archivos del Instituto de Cardiología de México》1978,48(6):1224-1232
A case is presented of Subacute Bacterial Endocarditis on a biological Duramater Prosthesis. In the evolution curse, the patient presented an intraparenchimal cerebral haemorrhage, where--upon the angiographic studies demonstrated the existence of a mycotic aneurysm in the left median cerebral arterial territory. With specific antibiotic therapy and replacement of the prosthesis, the clinical evolution of the case, was positive, and later angiographies evidenced the disappearance of the aneurysm. The incidence of intracranial mycotic aneurysm complicating bacterial endocarditis is relatively high (up to 4% in post-mortem series). There have been very few cases communicated up to now with angiographic demonstration. Mortality is similar in patients under surgical or medical treatment. The aetipothogenic aspects are discussed, as well as the recommended therapeutic measures. 相似文献
994.
Following a procedure described by Jones [12,13] boys and girls, 3 and 4 yr of age, were required to identify the sex of male and female faces tachistoscopically presented to the right and left visual fields. The results were in close conformity to those obtained with adults [12,13]. Boys showed a strong and consistent right visual field advantage in accuracy. Girls showed no strong field advantage. It is argued that cerebral lateralization remains constant across development. Theoretical issues relating to sex differences in cerebral lateralization are discussed. 相似文献
995.
Neurons and processes in the stingray retina can be stained using PAP immunohistochemistry and an antibody to serotonin, without pharmacological pretreatment. Most of the cell bodies are in the inner nuclear layer while the processes ramify in the inner plexiform layer suggesting the presence of a population of serotonin containing amacrine cells in this species. Scattered immunopositive axons were observed in the optic nerve from the optic chiasm to the optic nerve head. 相似文献
996.
The laryngeal mask airway (LMA) is being used with increasing frequency since its introduction into the United States in 1991. Currently, the LMA is being used in the United States in approximately one third of all operations or greater than 100 million surgeries. In Britain, where it was first introduced for use in 1988, the LMA is estimated to be used in up to 50% of cases. Not only has its use in elective cases increased, but the scope of indications for the LMA has also grown. Its use in emergent and difficult airway management has increased, and new LMA products have been introduced to address the limitations of the classic model. As the LMA has increased in popularity, however, so has the incidence of LMA-related complications. Cases of mucosal trauma, hematoma, tongue cyanosis, arytenoid dislocation, and lingual, hypoglossal, and recurrent laryngeal nerve paralyses have been documented in various anesthesia journals. Reports of these injuries are sparse in the otolaryngology literature. As otolaryngologists who will manage the sequelae of LMA-related injuries, we must remain cognizant of potential problems and their underlying mechanisms. We report a case of unilateral vocal cord paralysis, which required operative repair after the use of an LMA. We review the existing case reports, propose mechanisms of injury, and discuss practical applications of our findings. 相似文献
997.
Widen JE Johnson JL White KR Gravel JS Vohr BR James M Kennalley T Maxon AB Spivak L Sullivan-Mahoney M Weirather Y Meyer S 《American journal of audiology》2005,14(2):S200-S216
PURPOSE: This 3rd of 4 articles on a study of the efficacy of the 2-stage otoacoustic emission/automated auditory brainstem response (OAE/A-ABR) newborn hearing screening protocol describes (a) the behavioral audiometric protocol used to validate hearing status at 8-12 months of age, (b) the hearing status of the sample, and (c) the success of the visual reinforcement audiometry (VRA) protocol across 7 sites. METHOD: A total of 973 infants who failed OAE but passed A-ABR, in one or both ears, during newborn screening were tested with a VRA protocol, supplemented by tympanometry and OAE screening at age 8-12 months. RESULTS: VRA audiograms (1.0, 2.0, and 4.0 kHz) were obtained for 1,184 (82.7%) of the 1,432 study ears. Hearing loss was ruled out in another 100 ears by VRA in combination with OAE, for a total of 88.7% of the study sample. Permanent hearing loss was identified in 30 ears of 21 infants. Sites differed in their success with the VRA protocol. CONCLUSIONS: Continued monitoring of hearing beyond the newborn period is an important component of early detection of hearing loss. Using a structured protocol, VRA is an appropriate test method for most, but not all, infants. A battery of test procedures is often needed to adequately delineate hearing loss in infants. Examiner experience appears to be a factor in successful VRA. 相似文献
998.
Binaural redundancy and inter-aural time difference cues for patients wearing a cochlear implant and a hearing aid in opposite ears 总被引:1,自引:0,他引:1
We investigated speech perception advantages arising from the use of inter-aural time difference cues, and from the provision of redundant information by the use of a hearing aid contralateral to a cochlear implant (bimodal hearing devices). Thirty-eight subjects (14 normally hearing and 23 hearing-impaired) participated in this study. The effect of binaural redundancy was assessed by comparing the signal-to-noise ratio (SNR) required for 50% correct identification of sentences in noise when listening monaurally to that when listening binaurally. The use of inter-aural time difference cues was determined by comparing the binaural SNRs obtained with or without a noise delay of 700 micros between ears. Results indicated adults who used bimodal hearing devices benefited from binaural redundancy, but children did not. Whereas normally hearing subjects used inter-aural time difference cues to improve speech perception in noise, neither adults nor children who used bimodal hearing devices were able to do so. 相似文献
999.
Shi J Shibayama A Liu Q Nguyen VQ Feng J Santos M Temudo T Maciel P Sommer SS 《Human mutation》2005,25(5):505
Fifty to eighty percent of Rett syndrome (RTT) cases have point mutations in the gene encoding methyl-CpG-binding protein-2 (MECP2). A fraction of MECP2 negative classical RTT patients has large heterozygous deletions. Robust Dosage PCR (RD-PCR) assays were developed as a rapid, convenient and accurate method to detect large heterozygous deletions and duplications. A blinded analysis was performed for 65 RTT cases from Portugal by RD-PCR in the coding exons 2-4 of the MECP2 gene. Neither the patients with point mutations nor the non-classical RTT patients without point mutation had a deletion or duplication. One of remaining eight female patients with classical RTT without point mutation had a heterozygous deletion. This is the first report of a deletion spanning the entire MECP2 gene. The deletion was confirmed by Southern blotting analysis and the deletion junction was localized 37 kb upstream from exon 1 and 18 kb downstream from exon 4. No duplications were detected. Our results suggest that RD-PCR is an accurate and convenient molecular diagnostic method. 相似文献
1000.
The dissociation between intact priming and reduced explicit memory in aging has been called into question on the basis of limited information that suggests that priming measures are less reliable than explicit memory measures. No aging study to date, however, has offered a comprehensive examination of the reliability of these measures. Age-related performance and test-retest stability coefficients for multiple priming and explicit memory tasks were compared. Age effects were found on some tasks but not others, and stability was not related to task performance. Stability was similar for implicit versus explicit task instructions, younger versus older persons, and studied versus unstudied items. Results indicate that dissociations between priming and explicit memory performances cannot be accounted for by differential reliability of the measures. 相似文献