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排序方式: 共有136条查询结果,搜索用时 31 毫秒
101.
Kempen GI Meier AJ Bouwens SF van Deursen J Verhey FR 《Tijdschrift voor gerontologie en geriatrie》2007,38(1):38-45
The Telephone Interview Cognitive Status (TICS) is an instrument to screen for dementia in older persons by telephone. Although the psychometric properties of the TICS have been studied in various countries, the quality of the Dutch version of the TICS was yet unknown. This paper presents the Dutch version of the TICS and reports on its reliability and validity among 51 patients of Maastricht University Hospital, The Netherlands. The Pearson and intra-class correlations for test-retest reliability were 0.93 and 0.92, respectively. The Pearson and intra-class correlations for inter-rater reliability were 0.91 and 0.90, respectively. Sensitivity and specificity were studied in relation to the Mini Mental State Examination (MMSE, cut-off point 23/ 24) and the diagnosis of dementia as assessed according to DSM-IV criteria. When using the TICS cut-off point of 26/27, the coefficients for sensitivity and specificity were at least 0.80. The percentages ROC under the curve were 90% and 93% with the MMSE and the diagnosis dementia as criterion, respectively. We conclude that the Dutch version of the TICS is an acceptable instrument for screening for dementia in older persons, particularly when face-to-face contact is not possible. 相似文献
102.
Kempen GI Zijlstra GA van Haastregt JC 《Tijdschrift voor gerontologie en geriatrie》2007,38(4):204-212
Fear of falling is common in older persons. Different methods have been developed to assess fear of falling. The most well-know measure is the 10-item Falls Efficacy Scale (FES). However, the FES items (a) focus on low functioning older persons and particularly on in-home activities, (b) do not comprise social activities, and (c) were developed from a US perspective so that translation in European languages is hampered. To solve these issues, the 16-item Falls Efficacy Scale-International (FES-I) was recently developed within the Prevention of Falls Network Europe (ProFaNE). In this article, the Dutch version of the FES-I is presented and the psychometric properties in 213 Dutch persons aged 70 years of age and over are described. The FES-I showed to be unidimensional and internally consistent; the Cronbach alpha coefficient was 0.96. The 4 week test-retest intra-class correlation coefficient was 0.82. The associations of the FES-I sumscores with age, gender, falls history and overall fear of falling was as expected, indicating construct validity. In addition, the FES-I discriminated in the same extent as the original 10-item FES scale. We conclude that the FES-I showed acceptable reliability and construct validity and may be useful in cross-national research. Future studies should focus on the sensitivity to change of FES-I. 相似文献
103.
Koster A Penninx BW Newman AB Visser M van Gool CH Harris TB van Eijk JT Kempen GI Brach JS Simonsick EM Houston DK Tylavsky FA Rubin SM Kritchevsky SB 《Obesity (Silver Spring, Md.)》2007,15(12):3122-3132
Objective: This study examines the association between incident mobility limitation and 4 lifestyle factors: smoking, alcohol intake, physical activity, and diet in well‐functioning obese (n = 667) and non‐obese (n = 2027) older adults. Research Methods and Procedures: Data were from men and women, 70 to 79 years of age from Pittsburgh, PA and Memphis, TN, participating in the Health, Aging and Body Composition (Health ABC) study. In addition to individual lifestyle practices, a high‐risk lifestyle score (0 to 4) was calculated indicating the total number of unhealthy lifestyle practices per person. Mobility limitation was defined as reported difficulty walking 1/4 mile or climbing 10 steps during two consecutive semiannual assessments over 6.5 years. Results: In non‐obese older persons, significant risk factors for incident mobility limitation after adjustment for socio‐demographics and health‐related variables were current and former smoking [hazard ratio (HR) = 1.51; 95% confidence interval (CI), 1.20 to 1.89; HR = 1.40; 95% CI, 1.12 to 1.74), former alcohol intake (HR = 1.30; 95% CI, 1.05 to 1.60), low and medium physical activity (HR = 1.78; 95% CI, 1.45 to 2.18; HR = 1.29, 95% CI, 1.07 to 1.54), and eating an unhealthy diet (HR = 1.57; 95% CI, 1.17 to 2.10). In the obese, only low physical activity was associated with a significantly increased risk of mobility limitation (HR = 1.44; 95% CI, 1.08 to 1.92). Having two or more unhealthy lifestyle factors was a strong predictor of mobility limitation in the non‐obese only (HR = 1.98; 95% CI, 1.61 to 2.43). Overall, obese persons had a significantly higher risk of mobility limitation compared with non‐obese persons, independent of lifestyle factors (HR = 1.73; 95% CI, 1.52 to 1.96). Conclusions: These results underscore the importance of a healthy lifestyle for maintaining function among non‐obese older adults. However, a healthy lifestyle cannot overcome the effect of obesity in obese older adults; this stresses the importance of preventing obesity to protect against mobility loss in older persons. 相似文献
104.
MI YOON CHUNG MYONG GI CHUNG 《Botanical journal of the Linnean Society. Linnean Society of London》2007,155(2):161-169
Levels of allozyme variation, population genetic structure, and fine-scale genetic structure (FSGS) of the rare, both sexually and clonally reproducing terrestrial orchid Epipactis thunbergii were examined for eight ( N = 734) populations in a 20 × 20-km area in South Korea. Twenty-three putative allozyme loci resolved from 15 enzyme systems were used. Extremely low levels of allozyme variation were found within populations: the mean frequency of polymorphic loci was 3.8% [isocitrate dehydrogenase ( Idh-2 ) with two alleles was polymorphic across populations], the mean number of alleles per locus was 1.04, and the mean expected heterozygosity was 0.013. The overall fixation index was not significantly different from zero ( F IS = 0.069), although the species is self-compatible. However, a significantly high degree of population differentiation was found between populations at Idh-2 ( F ST = 0.388) in the studied area. Furthermore, spatial autocorrelation analyses revealed a significant FSGS (up to 3 m) within populations. These observations suggest that the main explanatory factors for the extremely low levels of genetic diversity and the shaping of the population genetic structure of E. thunbergii are genetic drift as a result of a small effective population size, a restricted gene flow, and the isolation of populations. Considering the current genetic structure of E. thunbergii , three guidelines are suggested for the development of conservation strategies for the species in South Korea: (1) protection of habitats of standing populations; (2) prohibition by law of any collection of E. thunbergii ; and (3) protection of nearby pollinator populations, given the fact that fruit set in natural habitats is very low. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 161–169. 相似文献
105.
1. The effects of secretin and pancreozymin-C-octapeptide and phosphodiesterase inhibitors on the concentration of adenosine 3',5'-cyclic monophosphate (cyclic AMP) and on the release of enzymes from rat pancreas have been studied. 2. In determininging cyclic AMP by means of the saturation assay of Brown et al. ((1971) Biochem. J. 121, 561-563) it is found essential to purify the pancreatic tissue extract by ion-exchange chromatography prior to the assay. 3. Injection of synthetic secretin or pancreozymin-C-octapeptide in anaesthetized rats in a secretory active dose (0.1 nmol) has no effect on the pancreatic cyclic AMP level. 4. Incubation for up to 10 min of pancreatic slices in Krebs-Ringer bicarbonate glucose medium containing 10(-2) M theophylline as phosphodiesterase inhibitor does not result in an increase of the cyclic AMP level. With 10(-2) M 1-methyl-3-isobutylxanthine as phosphodiesterase inhibitor the level is more than doubled after the first min of incubation and remains constant thereafter. 5. Addition of 3-10(-7) M secretin to slices incubated in the presence of 10(-2) M theophylline causes 84% increase of the cyclic AMP level above control, whereas the addition of 3-10(-7) M pancreozymin-C-octapeptide has no significant effect. In the presence of 10(-2) M 1-methyl-3-isobutylxanthine the latter hormone causes significant increases of up to 34% above control during 10 min of incubation. Secretin in this condition augments the cyclic AMP level by up to 296% above control during a 10 min incubation period. Addition of secretin and pancreozymin-C-octapeptide together has no greater effect than of secretin alone. 6. A broken cell fraction of rat pancreas contains adenylate cyclase activity which can be stimulated to 457 and 600% above the basal activity by 3-10(-7) M pancreozymin-C-octapeptide and secretin, respectively. Incubation of pancreatic slices with either hormone has no effect on the cyclic AMP phosphodiesterase activity in the homogenate of these slices. 7. Pancreozymin-C-octapeptide, dibutyryl cyclic AMP, 1-methyl-3-isobutylxanthine and carbamylcholine cause an elevated release of chymotrypsin from pancreatic slices incubated for 2 h in Krebs-Ringer bicarbonate medium, containing 10 mM glucose, while secretin, cyclic AMP and butyric acid have no significant effect. The release of the cytoplasmic enzyme lactate dehydrogenase is also elevated by dibutyryl cyclic AMP, 1-methyl-3-isobutylxanthine and carbamylcholine, but not significantly by pancreozymin-C-octapeptide. 8. The results support the role of cyclic AMP in the action of secretin, and do not exclude a mediating function of this nucleotide in the actions of pancreozymin in rat pancreas. 相似文献
106.
Some properties of rat brain phenol sulphotransferase were investigated in in vitro at pH7.4. The enzyme was purified 10-fold by chromatography on DEAE-Sephadex -50. It can be assayed with 4-hydroxy-3-methoxyphenylethylene glycol or 4-methylumbelliferone as the sulphate acceptor. The partially purified enzyme is stable for at least 1 week when stored at 4 degrees C. It is, however, additionally activated (10--20%) and stabilized by 1 mM-dithiothreitol. The activity of the enzyme does not depend on the addition of exogenous Mg2+. The pH optima for the sulphation of 4-hydroxy-3-methoxyphenylethylene glycol and 4-methylumbelliferone are 7.8 and 7.4 respectively. Substrate inhibition by the sulphate acceptor is apparent at concentrations over 0.05mM. Initial-velocity studies in the absence and presence of product and dead-end inhibitors suggested that the mechanism of the rat brain sulphotransferase reaction is sequential ordered Bi Bi with a dead-end complex of enzyme with adenosine 3',5'-biphosphate and sulphate acceptor. The sulphate donor adenosine 3'-phosphate 5'-sulphatophosphate is the first substrate that adds to the enzyme, and the sulphate acceptor is the second substrate. The dissociation constant for the complex of enzyme with sulphate donor is 21 micron. The sulphated substrate is the first product and adenosine 3',5'-biphosphate is the second product that leaves the enzyme. 相似文献
107.
A new assay of catechol O-methyltransferase (EC 2.1.1.6) is described by determination of the m- and p-O-methylated products of 3,4-dihydroxybenzoic acid. The method involves DEAE-Sephadex A-25 chromatography and reversed-phase high-performance liquid chromatography on a LiChrosorb 5 RP 18 column. The liquid chromatographic solvent system consisted of 0.05 m acetic acid in methanol:water (1:4, ), pH 3,2. meta/para ratios of O-methylation are easily obtained by this method. Dimethylation has not been observed with a partially purified enzyme preparation from rat liver. 相似文献
108.
J Kwekkeboom H J Kempen E M van Voorthuizen M Griffioen L H Cohen 《Biochimica et biophysica acta》1990,1042(1):146-149
Activities of 3-hydroxy-3-methylglutaryl-CoA reductase, squalene synthetase and cholesterol 7 alpha-hydroxylase, measured in liver microsomal preparations from domestic swine between birth and adolescence, correlated strongly in individual animals. A synchronous increase was observed between 4 and 6 weeks after birth, i.e., immediately after weaning. Rise in activity was highest for HMG-CoA reductase (30-fold), and smallest for squalene synthetase (5-fold). In pubertal pigs (16 to 30 weeks old), activities of these enzymes had the same low values as in suckling piglets. The increase of both HMG-CoA reductase and squalene synthetase activities may be caused by the shift from high-cholesterol milk intake to a chow diet with low-cholesterol content. The rise in cholesterol 7 alpha-hydroxylase activity might be due to other dietary or hormonal factors. 相似文献
109.
Cholesterol 7 alpha-hydroxylase activity and bile acid synthesis in hepatocytes of unweaned and weaned pigs in monolayer culture 总被引:1,自引:0,他引:1
J Kwekkeboom H M Princen E M van Voorthuizen H J Kempen 《Biochimica et biophysica acta》1990,1042(3):386-394
Activity of cholesterol 7 alpha-hydroxylase (EC 1.14.13.17) in freshly isolated hepatocytes from unweaned piglets (2 to 3 weeks old) was 16-times lower as compared to hepatocytes from weaned piglets (7 to 8 weeks old). The monolayer culture activity of the enzyme remained low in unweaned piglet hepatocytes. In contrast, in cultured hepatocytes from weaned piglets, cholesterol 7 alpha-hydroxylase activity declined during the first day of culture, but was restored during the next 2 culture days, provided that fetal bovine serum (10%) was added to the culture medium. Addition of dexamethasone (50 nM) and insulin (135 nM) to the medium, further enhanced cholesterol 7 alpha-hydroxylase activity to values similar to those in freshly isolated hepatocytes and retarded the decline of enzyme activity after the 3rd culture day. Cultured hepatocytes from weaned and unweaned piglets synthesized similar types of bile acids from [14C]cholesterol, among which hyocholic acid (the most prominent), hyodeoxycholic acid, chenodeoxycholic acid, murocholic acid and lithocholic acid could be identified. 95% of radiolabelled bile acids synthesized was conjugated, mainly with glycine, but also with taurine, sulfate and glucuronic acid. The rate of mass production of bile acids by cultured hepatocytes of weaned piglets (as measured by gas-chromatography) parallelled cholesterol 7 alpha-hydroxylase activity, and was low in the absence of serum, but increased in medium containing fetal bovine serum, dexamethasone and insulin to a rate lying in the range of 75% of the in vivo bile acid production during the 3rd culture day. Bile acid production by unweaned piglet hepatocytes was 3-times lower under these conditions. It is concluded that hepatocytes from young weaned pigs cultured in medium containing 10% fetal bovine serum, offer a suitable in vitro model for the study of bile acid synthesis, in view of the high cholesterol 7 alpha-hydroxylase activities and bile acid production rates. 相似文献
110.
Elisah Antonia van Kempen Eirini Spiliotopoulou Goran Stojanovski Sander de Leeuw 《The International Journal of Life Cycle Assessment》2017,22(11):1718-1730