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991.
Han C.G. Kemper E.A.L.M. Verhagen D. Milo G.B. Post F. Van Lenthe W van Mechelen J.W.R. Twisk W W de Vente 《American journal of human biology》2002,14(4):448-456
In the Amsterdam Growth and Health Longitudinal Study (AGAHLS), a group of apparently healthy males and females (n = 200) were interviewed about their physical activities on eight separate occasions over a period of 20 years between 13 and 33 years of age (multi‐measured group: MM). Information about their health was given based on their personally measured lifestyle (activity, diet, smoking) and biological risk characteristics for chronic diseases (medical check‐ups). A comparable group of boys and girls (n = 200) was only measured on two occasions (bi‐measured group: BM): at 13 and 33 years. Physical activity was estimated with a structured interview. Total physical activity and sports activity were estimated in three intensity levels (light, moderate, and heavy). It was hypothesized that the eight repeated medical check‐ups with health information in the MM group would result in a healthier lifestyle with respect to the determinants and levels of habitual physical activity compared to the BM group. Contrary to the hypothesis, males and females in the BM group showed a significantly higher increase or a lower decrease in physical activities compared to the MM group. This negative effect on the physical activity pattern at 33 years in the MM group may have been caused by more underreporting of physical activities than in the BM group. In conclusion, there does not appear to be a significant effect of long‐term (multi‐measured) health information with medical check‐ups during adolescence and young adulthood on level of physical activity in males and females at 33 years of age. Am. J. Hum. Biol. 14:448–456, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
992.
The acrosome index, radical buffer capacity and number of isolated progressively motile spermatozoa predict IVF results 总被引:2,自引:0,他引:2
Rhemrev JP Menkveld R Roseboom TJ van Overveld FW Teerlink T Lombard C Vermeiden JP 《Human reproduction (Oxford, England)》2001,16(9):1885-1892
BACKGROUND: The accuracy by which a number of newly described semen variables can predict either total fertilization failure (TFF) or pregnancy outcome in IVF, has not previously been investigated. The study aim was, therefore, to determine prospectively the predictive value of these variables. METHODS: The semen variables investigated were the post-wash total progressively motile sperm cell count (TPMC(post-wash)), the acrosome index (AI), 'cytoplasmic residues' and normal sperm morphology, evaluated according to the strict criteria ('strict criteria'), as well as the fast and slow total radical trapping antioxidant potential ('fast TRAP' and 'slow TRAP' respectively). RESULTS: The study group (n = 87) showed a mean (+/- SD) number of 10.2 +/- SD retrieved oocytes, 12.6% TFF, a mean fertilization rate of 59.7% and a pregnancy rate of 19.5% (17/87). TFF was significantly predicted by TPMC(post-wash), 'strict criteria', AI and 'cytoplasmic residues' (all P < 0.05). The outcome after embryo transfer was significantly predicted by AI and 'fast TRAP'. Semen samples with an AI <5% and a 'fast TRAP' <1.14 mmol/l in particular did not result in any pregnancies after IVF-embryo transfer. CONCLUSIONS: Of all the measured and calculated semen variables, TPMC(post-wash) was the best predictor of TFF, whilst AI and 'fast TRAP' were the best predictors of pregnancy after IVF. 相似文献
993.
Initial validation of the SLEEP-50 questionnaire 总被引:1,自引:0,他引:1
Initial psychometric properties of the SLEEP-50 questionnaire, designed to detect sleep disorders as listed in the Diagnostic and Statistical Manual of Mental Disorders (4th ed., Text Revision), were examined. The sample consisted of 377 college students, 246 sleep patients, 32 nightmare sufferers, and 44 healthy volunteers. The internal consistency was high (Cronbach's alpha = .85); test-retest correlations fell between .65 and .89. Principal component analysis with a direct oblimin rotation revealed a factor structure that closely matched the designed structure. Sensitivity and specificity scores were promising for all sleep disorders; the agreement between all clinical diagnoses and SLEEP-50-classifications was substantial (kappa = .77). These initial findings indicate that the SLEEP-50 seems able to detect a variety of sleep disorders. The SLEEP-50 can aid in screening for common sleep disorders in the general population. 相似文献
994.
Differences in assembly or stability of complex I and other mitochondrial OXPHOS complexes in inherited complex I deficiency 总被引:9,自引:0,他引:9
Ugalde C Janssen RJ van den Heuvel LP Smeitink JA Nijtmans LG 《Human molecular genetics》2004,13(6):659-667
NADH-ubiquinone oxidoreductase (complex I) deficiency is amongst the most encountered defects of the mitochondrial oxidative phosphorylation (OXPHOS) system and is associated with a wide variety of clinical signs and symptoms. Mutations in complex I nuclear structural genes are the most common cause of isolated complex I enzyme deficiencies. The cell biological consequences of such mutations are poorly understood. In this paper we have used blue native electrophoresis in order to study how different nuclear mutations affect the integrity of mitochondrial OXPHOS complexes in fibroblasts from 15 complex I-deficient patients. Our results show an important decrease in the levels of intact complex I in patients harboring mutations in nuclear-encoded complex I subunits, indicating that complex I assembly and/or stability is compromised. Different patterns of low molecular weight subcomplexes are present in these patients, suggesting that the formation of the peripheral arm is affected at an early assembly stage. Mutations in complex I genes can also affect the stability of other mitochondrial complexes, with a specific decrease of fully-assembled complex III in patients with mutations in NDUFS2 and NDUFS4. We have extended this analysis to patients with an isolated complex I deficiency in which no mutations in structural subunits have been found. In this group, we can discriminate between complex I assembly and catalytic defects attending to the fact whether there is a correlation between assembly/activity levels or not. This will help us to point more selectively to candidate genes for pathogenic mutations that could lead to an isolated complex I defect. 相似文献
995.
Evidence for the involvement of a Bemisia tabaci GroEL homologue in the transmission of tomato yellow leaf curl geminivirus (TYLCV) is presented. A approximately 63-kDa protein was identified in B. tabaci whole-body extracts using an antiserum raised against aphid Buchnera GroEL. The GroEL homologue was immunolocalized to a coccoid-shaped whitefly endosymbiont. The 30 N-terminal amino acids of the whitefly GroEL homologue showed 80% homology with that from different aphid species and GroEL from Escherichia coli. Purified GroEL from B. tabaci exhibited ultrastructural similarities to that of the endosymbiont from aphids and E. coli. In vitro ligand assays showed that tomato yellow leaf curl virus (TYLCV) particles displayed a specific affinity for the B. tabaci 63-kDa GroEL homologue. Feeding whiteflies anti-Buchnera GroEL antiserum before the acquisition of virions reduced TYLCV transmission to tomato test plants by >80%. In the haemolymph of these whiteflies, TYLCV DNA was reduced to amounts below the threshold of detection by Southern blot hybridization. Active antibodies were recovered from the insect haemolymph suggesting that by complexing the GoEL homologue, the antibody disturbed interaction with TYLCV, leading to degradation of the virus. We propose that GroEL of B. tabaci protects the virus from destruction during its passage through the haemolymph. 相似文献
996.
A Smits D Smeets B Hamel J Dreesen B van Oost 《American journal of medical genetics》1992,43(1-2):345-352
The overall prevalence of the fragile X [fra(X)] mutation, as determined by population studies, is approximately 1 in 850 [Gustavson et al., 1986; Webb et al., 1986]. This prevalence suggests a very high mutation rate which, in turn, suggests that many patients have to represent sporadic cases. In order to obtain an accurate estimate of the proportion of sporadic cases, we performed genealogic, cytogenetic and DNA linkage studies as well as direct analysis of the CGG repeat in relatives of 84 fra(X) probands. We did not find any evidence for the presence of sporadic cases. In 11 probands consanguinity could be proven by the detection of common ancestors, in 5 related families up to 9 generations ago. In the other 6 related families the mutation could be traced back 4-6 generations. In 3 or more generation families we were able to demonstrate that half of the probands carried the grandpaternal fra(X) gene. These results imply that rather than a high mutation rate, both Normal Transmitting Males (NTM's) and mentally normal female carriers contribute considerably to the high prevalence of the fra(X) syndrome. 相似文献
997.
998.
Wim H. J. P. Linssen Martin J. Van den Bent Han G. Brunner Petra J. E. Poels 《American journal of medical genetics. Part A》1994,51(1):81-82
We report on 3 sibs (2 males and one female) with sensorineural deafness. The presence of ovarian dysgenesis in the girl suggested a diagnosis of Perrault syndrome. In addition our patients have a sensory polyneuropathy and amelogenesis imperfecta. Two of the patients have mild mental retardation, fine choreatic movements, and dyspraxia. It is discussed whether these findings are part of a separate clinical entity or should be included within the spectrum of the Perrault syndrome. © 1994 Wiley-Liss, Inc. 相似文献
999.
Determination of serum bactericidal activity against Escherichia coli by an automated photometric method 下载免费PDF全文
F Crokaert M J Lismont M P van der Linden E Yourassowsky 《Journal of clinical microbiology》1988,26(10):2069-2076
The resistance of gram-negative bacteria to complement-mediated serum activity is supposedly an important virulence factor. However, the lack of standardization in the methods used to determine serum activity and the many definitions applied make the comparisons between studies very difficult. We developed a rapid photometric method that we compared with a classical killing one. Escherichia coli in the exponential phase of growth in brain heart infusion broth (final inoculum, 10(7) CFU/ml) at 35 degrees C was added to 50% human serum in Veronal buffer. Viable counts and automatic recording of the variations in the optical densities were obtained for 40 E. coli strains isolated from the stools of healthy adults. With the viable count method, 17 (42.5%) were susceptible (at least a 1 log CFU/ml decrease), 17 (42.5%) were resistant (a 0.6 log CFU/ml increase), 4 (10%) were intermediate (poorly growing inoculum or a decrease of less than 1 log CFU/ml), and 2 could not be classified (nonreproducible results). Agreement between both methods was observed for 87.5% of the stool strains. Eight reference strains of known susceptibilities were classified identically by both methods, leading to a final concordance rate of 89.6%. A total of 129 blood isolates were tested by the photometric method: 64 (49.6%) were resistant, 50 (38.8%) were susceptible 5 (3.9%) showed early regrowth, and 10 (7.7%) were not perfectly reproducible. Of these 129 blood isolates, 5 were also tested by the killing method: 37 (49%) were resistant, 32 (43%) were susceptible, and 6 (8%) were intermediate. The concordance rate between both assays was 89% for the blood isolates; when the minor discordances were ruled out, it was 97%. This automated method could be a useful screening tool for detecting resistance to serum in clinical trials and for studying the in vitro variations of this property. 相似文献
1000.
Immunomodulation with liposomes: the immune response elicited by liposomes with entrapped dichloromethylene-diphosphonate and surface-associated antigen or hapten 总被引:2,自引:0,他引:2 下载免费PDF全文
Macrophages in the murine spleen were eliminated by the intravenous administration of dichloromethylene-diphosphonate (DMDP) encapsulated in liposomes. The immune response against an antigen (bovine serum albumin, BSA) or hapten (dinitrophenyl, DNP) associated with the surface of the DMDP liposomes was studied. Significant effects of macrophage elimination on the primary (IgM), but not on the secondary (IgG), anti-BSA response were found. Dramatic effects on the response against liposome-associated DNP were observed in macrophage-depleted mice. The number of anti-DNP antibody-forming cells in the spleen decreased from 300 to 28 per section, and anti-DNP serum titres dropped to 12% of their normal values. Since a similar phenomenon was observed for TNP-Ficoll, a thymus-independent type-2 antigen (and not for thymus-dependent or thymus-independent type-1 antigens), we suggest that this response should be classified as thymus-independent type-2 on grounds of its in vivo behaviour. We conclude that adjuvant activity (and memory formation) of liposomes with antigen exposed on their surface occurs irrespective of the presence or absence of splenic macrophages, and that DMDP liposomes could be useful in drug targeting with antigenic liposomes. 相似文献