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21.
AIM: Falling is a serious medical problem for elderly persons. This study was done to look at prevalence and risk factors for falls in community dwelling elderly in Singapore. METHOD: A random sample of 3,000 persons aged 60 years and above was chosen from a database based on the 1990 population census. Letters were sent out to 2,582 subjects who had local and complete addresses. In the letter, they were informed about the purpose of the survey, and invited to participate in a questionnaire and clinical health screening at an appointed date at a polyclinic. Participants were reminded the day before their appointment by telephone, and a new appointment could be given at the subject's convenience. RESULTS: We found a prevalence rate of falls of 17.2%. Two-thirds of these had single falls, while one-third had recurrent falls, defined as having more than one fall within the previous one year. The following factors were found to be significantly associated with increase falling in the elderly: age > or = 75 years (O.R. = 1.82, 95% C.I. 0.95-3.50), female sex (O.R. = 2.5, 95% C.I. 1.40-4.48), Malay race (O.R. = 2.66, 95% C.I. 1.21-5.86), poor vision (O.R. = 1.7, 95% C.I. 0.99-2.90), Barthel's score of less than 20 (O.R. = 1.76, 95% C.I. 0.94-3.28), those taking 2 or more drugs daily (O.R. = 2.1, 95% C.I. 1.22-3.72) and the presence of hypertension (O.R. = 1.78, 95% C.I. 1.06-3.01). Fall rate is also twice as high in women as in men. At the same time, we found that women in the group we studied also tend to exercise less than the men. Fallers also had significantly more mobility and activities of daily living (ADL) disabilities (reflected by a lower Barthel's score) and this is consistent with other results. The only factor that reduced the risk of falling was regular exercise (O.R. = 1.64, 95% C.I. 0.93-2.93). CONCLUSION: In our study, we found differences between the group with single and recurrent falls. In the group with single falls, the fall tend to occur outdoors (O.R. = 2.97, 95% C.I. 1.03-8.60) and during the day (O.R. = 3.47, 95% C.I. 1.20-10.0), tend to be accidental (O.R. = 3.16, 95% C.I. 1.05-9.50) and tend to seek medical attention (O.R. = 3.68, 95% C.I. 1.23-11.0). Overall, 32 persons (46.4%) seek medical treatment after their falls, and of these, 65.6% were women. Risk factors for falls should be screened for all elderly.  相似文献   
22.
Thirty-one right-hemisphere lesioned (RHL) patients, 11 left-hemisphere lesioned patients (LHL) and 10 normal controls (NC) bisected lines in three spatial location and four directional cuing conditions. The error direction and error size were analyzed as separate and combined variables. Seventy-seven percent of RHL patients and 45% of LHL patients made abnormally large errors in line bisection. Right-hemisphere lesioned patients were more sensitive to spatial location and directional cuing than NC subjects. In contrast, LHL patients were less sensitive to either condition than NCs. The error direction and error size emerged as dissociable components of line bisection. Right-hemisphere lesioned patients and NC subjects bisected lines consistently to one side of the true center. Left-hemisphere lesioned patients bisected lines equally often on both sides of the true center. Both RHL and LHL patients made larger absolute bisection errors than NC subjects, but the RHL patient's errors were larger than those of the LHL patients. We propose that the greater sensitivity of RHL patients to spatial location and directional cues and the directional consistency of their bisection errors represent contributions of the intact left cerebral hemisphere to line bisection. In contrast, the LHL patient's unrestrained ability to orient to both ends of the line reflects a contribution of the intact right cerebral hemisphere to line bisection. The failure of both groups to accurately bisect lines reflects a common visuospatial processing deficit that is more pronounced following RHLs than LHLs.  相似文献   
23.
Cytokines and insulin-like growth factors (IGFs) are involved in the induction and/or perpetuation of inflammatory bowel disease. The effect of fasting on inflammatory bowel disease was studied in a mouse experimental model of acute colitis caused by adding dextran sulfate sodium (DSS) to drinking water. Animals were either fed ad libitum or fasted (water only) for 2 days before death. Inflammation and tissue damage, measured as a colitis activity score, were markedly reduced in fasted (2.4 +/- 0.1) compared to fed (5.3 +/- 0.1) DSS animals (P < 0.0001). Colon interleukin-1 beta (IL-1 beta), IGF-I, and tumor necrosis factor-alpha messenger RNAs (mRNAs) were quantified by Northern blot hybridization and expressed as a percentage of mRNA abundance in fed controls. In DSS mice, IL-1 beta mRNA was elevated in the fed group (954 +/- 155%; P < 0.001), but was suppressed in fasted animals (71.1 +/- 11%). IGF-I mRNA also was elevated in fed DSS mice (421 +/- 71%; P < 0.01). This increase was attenuated in fasted DSS mice (202 +/- 17%; P < 0.01 compared to fed DSS mice). Tumor necrosis factor-alpha mRNA was increased in fed DSS mice (162 +/- 15%; P < 0.01), but was not significantly lower in fasted animals. By in situ hybridization, IL-1 beta mRNA was localized to the lamina propria of colonic mucosa in fed DSS animals, but was not detectable in other groups. We conclude that fasting has a protective effect on the progression of acute DSS, induced colitis. This is associated with decreased expression of IL-1 beta and IGF-I mRNAs in the colon.  相似文献   
24.
Monoclonal antibodies derived from the actin multigene family are routinely used as an adjunct to morphologic diagnoses of smooth muscle tumors. Northern blot analysis was performed on 60 surgical resections utilizing isoactin-specific cDNAs. A comparison of this analysis to immunohistochemical studies demonstrated that actin-specific monoclonal antibodies represent reliable markers of the smooth muscle lineage. Smooth muscle neoplasms showed a unique pattern of gamma-smooth muscle isoactin gene expression, providing a potentially valuable molecular adjunct to the morphologic diagnosis of uterine smooth muscle tumors.  相似文献   
25.
The sea urchin egg receptor for sperm is thought to be involved in species-specific sperm-egg interactions at the egg surface. Recent revisions in the deduced amino acid sequence of the cloned cDNAs indicate that the protein encoded does not possess the common structural hallmarks of a membrane protein. Thus, investigation of the localization and association of the protein with the egg surface is crucial. We describe and characterize a new monoclonal antibody raised against recombinant sperm receptor protein. This antibody, in conjunction with several polyclonal antibodies, was used to study the receptor protein in eggs. Immunoprecipitation studies indicated that the antibodies recognize the high Mr (ca. 350 K) sperm receptor protein which copurified with egg plasma membrane-vitelline layer complexes. The sperm receptor protein was solubilized only by detergents and not by treatments designed to solubilize peripherally associated or lipid-anchored membrane proteins, suggesting a tight association with the membrane fraction. Confocal immunofluorescence microscopy of live eggs indicated surface staining. Finally, lysylendoproteinase C treatment of live eggs resulted in a loss of the high Mr receptor protein epitopes, and the concomitant release of a 70-kDa proteolytic fragment, which correlated with a reduced ability of the eggs to be fertilized. Taken together, these data indicate that at least some fraction of the sperm receptor protein is present on the egg surface, a requisite locale for a sperm binding protein.  相似文献   
26.
Chronic butylated hydroxytoluene (BHT) treatment after a single administration of a carcinogen increases lung tumor multiplicity in some inbred strains of mice. We report that BALB/cOla and BALB/cByJ mice given a low dose (10 microg/g of body weight) of 3-methylcholanthrene (MCA) develop no lung tumors unless this is followed by chronic BHT exposure. Slightly higher MCA doses (15 and 25 microg/g) induce low lung tumor multiplicities (0.6 and 1.9 tumors/mouse, respectively) that are increased 12-26-fold by chronic BHT administration. This low-dose MCA/BHT model in BALB mice will facilitate the identification of genes regulating susceptibility to lung tumor promotion and pulmonary chemopreventative agents that act at a postinitiation site.  相似文献   
27.
Investigation of the versatile models for autoimmunity of the ovary and other selected organs has contributed to our understanding of the following aspects of autoimmunity: the mechanism of T cell molecular mimicry; T-->B epitope spreading, as a basis for autoantibody diversification, and as a link between organ-specific and systemic autoimmunity; the localization of genetic loci potentially influencing multiple autoimmune diseases; and the elucidation of regulatory T cells as a component of physiological self tolerance.  相似文献   
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29.
We developed an akathisia rating scale for use with persons who have mental retardation and screened for the occurrence of akathisia in three samples: 66 adults receiving maintenance neuroleptic treatment, 20 adults not receiving neuroleptics, and 8 adults undergoing neuroleptic dose reduction. The scale had an acceptable level of interrater reliability and validly measured group differences related to neuroleptic treatment status. Using an empirically derived cut-off-score, we estimated the prevalence rate for akathisia to be 5% in neuroleptic-free subjects, 17% in neuroleptic-maintenance subjects, and 25% in neuroleptic-reduction subjects. Akathisia, dyskinesia, and stereotypy manifested as qualitatively different movement topograhies. The occurrence of dyskinesia stereotyped movement disorder was associated significantly with an increased occurrence of akathisia.  相似文献   
30.
Children are not just small adults. Perioperative nurses working with pediatric patients plan nursing interventions based on established principles of perioperative practice as well as incorporating concepts of growth and development relating to the child. A thorough assessment of the pediatric patient prior to surgery enables the perioperative nurse to plan for the surgical procedure, modifying as need be for the individual patient's specific needs. With adequate preparation, communication, and emotional support, the pediatric surgical experience can be positive for the child, parents, and perioperative team.  相似文献   
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