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51.
Nijhuis-van der Sanden MW Smits-Engelsman BC Eling PA Nijhuis BJ Van Galen GP 《Developmental neuropsychology》2002,22(3):643-670
The article aims to discriminate between 2 features that in principle both may be characteristic of the frequently observed poor motor performance in girls with Turner's syndrome (TS). On the one hand, a reduced movement speed that is independent of variations in spatial accuracy demands and therefore suggests a problem in motor execution. On the other hand, a disproportional slowing down of movement speed under spatial-accuracy demands, indicating a more central problem in motor programming. To assess their motor performance problems, 15 girls with TS (age 9.6-13.0 years) and 14 female controls (age 9.1-13.0 years) were tested using the Movement Assessment Battery for Children (MABC). In additionally, an experimental procedure using a variant of Fitts' graphic aiming task was used to try and disentangle the role of spatial-accuracy demands in different motor task conditions. The results of the MABC reestablish that overall motor performance in girls with TS is poor. The data from the Fitts' task reveal that TS girls move with the same accuracy as their normal peers but show a significantly lower speed independent of task difficulty. We conclude that a problem in motor execution is the main factor determining performance differences between girls with TS and controls. 相似文献
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53.
Sixteen obese patients, aged 19–31, and 27 normal weight individuals, aged 18–22, tasted and smelled fresh, unseasoned blended foods while blindfolded. Then they rated the foods on 51 semantic differential adjective scales which related to stimulation of the gustatory, olfactory, and trigeminal systems. The stimuli included fruits, vegetables, meat, fish, nuts, dairy products, grains, and a set of four standards: sucrose (sweet), NaCl (salty), lemon (sour), and coffee (bitter) in a thin cornstarch base. Proximity measures among stimuli for each subject were developed from the ratings on the adjective scales. Two multidimensional scaling (MDS) procedures, SINDSCAL (a variation of INDSCAL) and ALSCAL, were applied to the proximity measures yielding two-dimensional food maps which were very similar. Both MDS procedures provided weights for each subject on the two dimensions of the space common for all subjects. The weights indicated that the obese subjects found the first dimension, which was related to the hedonic and flavorous aspects of the stimuli, relatively more important than normal weight individuals. Also, obese subjects were significantly better at identifying the blended foods when compared to normal weight subjects. 相似文献
54.
Rademakers R Melquist S Cruts M Theuns J Del-Favero J Poorkaj P Baker M Sleegers K Crook R De Pooter T Bel Kacem S Adamson J Van den Bossche D Van den Broeck M Gass J Corsmit E De Rijk P Thomas N Engelborghs S Heckman M Litvan I Crook J De Deyn PP Dickson D Schellenberg GD Van Broeckhoven C Hutton ML 《Human molecular genetics》2005,14(21):3281-3292
55.
Phosphoinositide deficiency due to inositol depletion is not a mechanism of lithium action in brain 总被引:3,自引:0,他引:3
The "inositol depletion hypothesis" has been widely held to be the explanation for both the effect of lithium on brain function, apropos of its use in mood disorders, and on the impairment of development and induction of embryonic malformations in diverse organisms. The essence of the hypothesis is that a deficiency in cellular myo-inositol (Ins), secondary to lithium inhibition of inositol monophosphatase and/or multiple inositol polyphosphate phosphatase activities with trapping of Ins as inositol phosphates, leads to a depression of phosphatidylinositol (PtdIns) and a secondary impairment in inositide signaling. However, the ability of relatively low micromolar levels of Ins to reduce mammalian PtdIns synthetase activity in vivo has never been adequately tested. We have generated a lethal murine brain Ins deficiency model and measured PtdIns content using a novel MALDI-TOF MS method. Our results show that in the most severe Ins deficiency ever recorded in a mammal, the brain PtdIns levels do not decrease. We conclude that PtdIns deficiency due to "inositol depletion" is not a mechanism of lithium action in brain, and that Ins plays another unidentified role in the mammalian brain. 相似文献
56.
Safety of cryopreservation straws for human gametes or embryos: a study with human immunodeficiency virus-1 under cryopreservation conditions 总被引:3,自引:0,他引:3
57.
58.
Jennifer Knight Barry A. Gusterson Gerard Cowley Paul Monaghan 《Ultrastructural pathology》1984,7(2):133-141
We would like to thank John Ellis for expert photographic assistance, Mervin Jones and Linda Lovell for expert animal husbandry, and Dr. Dorothy Easty for establishing the cell line LICR-LON-HN-5, without which this study would not have been possible.
We report a light microscopic and ultrastructural analysis of the comparative degrees of differentiation seen in keratinocytes derived from the tongue and epidermis with those of a well-differentiated human squamous carcinoma cell line (LICR-LON-HN5). When growing on plastic substrates, all cultures had a similar morphology, with multilayering and the production of cornified envelopes. When cultured on collagen gels the structure was more organized, with keratohyalin granules and keratin whorl formation in both the normal and the malignant cultures. Normal keratinocytes injected into athymic mice produced epidermal cysts, while cells from the cell line produced well-differentiated squamous cell carcinomas, which were partially solid and partially cystic. The tumor was well organized, with identifiable basal cells, spin-ous cells, keratohyalin granules, and a prominent basal lamina at the stromal/epithelial interface. This model is to be developed for comparative studies between normal and malignant cells, with particular reference to basement membrane production and to investigations of the relative importance of extrinsic and intrinsic factors in the control of squamous differentiation. 相似文献
We report a light microscopic and ultrastructural analysis of the comparative degrees of differentiation seen in keratinocytes derived from the tongue and epidermis with those of a well-differentiated human squamous carcinoma cell line (LICR-LON-HN5). When growing on plastic substrates, all cultures had a similar morphology, with multilayering and the production of cornified envelopes. When cultured on collagen gels the structure was more organized, with keratohyalin granules and keratin whorl formation in both the normal and the malignant cultures. Normal keratinocytes injected into athymic mice produced epidermal cysts, while cells from the cell line produced well-differentiated squamous cell carcinomas, which were partially solid and partially cystic. The tumor was well organized, with identifiable basal cells, spin-ous cells, keratohyalin granules, and a prominent basal lamina at the stromal/epithelial interface. This model is to be developed for comparative studies between normal and malignant cells, with particular reference to basement membrane production and to investigations of the relative importance of extrinsic and intrinsic factors in the control of squamous differentiation. 相似文献
59.
A novel BRCA2 mutation in an Indonesian family found with a new, rapid, and sensitive mutation detection method based on pooled denaturing gradient gel electrophoresis and targeted sequencing 下载免费PDF全文
Purnomosari D Paramita DK Aryandono T Pals G van Diest PJ 《Journal of clinical pathology》2005,58(5):493-499
BACKGROUND: Breast cancer is increasing in Indonesia and other developing countries. Germline mutations in the BRCA1/2 genes are most strongly associated with a high risk for breast cancer development. There have been no reports on BRCA1/2 gene mutations in the Indonesian population. Genetic research yielding insight into mutations affecting the Indonesian population can help in risk assessment of individual patients. AIMS: To screen the BRCA1/2 genes for mutations in early onset Indonesian breast cancer patients and their families with a new, simple, and sensitive BRCA1/2 mutation screening strategy based on denaturing gradient gel electrophoresis (DGGE) and targeted sequencing. METHODS: DNA was isolated from the blood of four Indonesian breast cancer patients from high risk families and seven family members, and the polymerase chain reaction was performed with specially designed primers throughout the BRCA1/2 coding sequences to produce fragments suitable for pooled DGGE analysis. The aberrantly migrating samples were reamplified and sequenced. RESULTS: Two mutations were found in exons 13 and 16 of BRCA1 and two mutations in exons 2 and 14 of BRCA2, which turned out to be established polymorphisms according to the Breast Cancer Information Core. In addition, a novel 6 bp deletion in exon 11, leading to a premature stop, was found in BRCA2. CONCLUSION: Pooled DGGE and targeted sequencing revealed four BRCA1/2 polymorphisms and one novel BRCA2 mutation in a group of Indonesian patients at high risk of hereditary breast cancer. This illustrates that the proposed method is sensitive and particularly suited for screening unknown populations. 相似文献
60.
Gerard T. Williams FRCS Christopher J. Underwood B Sc David Charlesworth FRCS 《Annals of vascular surgery》1986,1(2):208-213
We report the early results of a series of 86 femoropopliteal bypass operations in which a 5 mm diameter thin wall polytetrafluoroethylene (Gore-Tex) prosthesis was used. Sixty-five bypasses were implanted in men and 21 in women. Thirty bypasses were done in conjunction with an aortic bifurcation graft and 18 patients had a bilateral procedure. The indication for operation was severe claudication in 74 cases and critical ischaemia in 12 cases. The angiographic run-off was good (three patent vessels) in 22 limbs and poor (one or two patent vessels) in 64 limbs. The cumulative patency rate for the whole group was 62% after 18 months. Angiographic run-off and the indication for operation were both found to influence cumulative patency rate significantly (p=0.035 and p=0.055, respectively). We also compared the results obtained when run-off was poor with equivalent data from our own previously published series in which a standard 6 mm diameter Gore-Tex prosthesis was used. This shows a difference in patency rate, for example 57% against 37% after 18 months, in favour of the smaller bore thin wall graft. 相似文献