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81.
82.
Disorders of conduction occurring simultaneously in both normal and accessory pathways of patients with Wolff-Parkinson-White (WPW) syndrome have only rarely been observed. To our knowledge this is the first report of impaired conduction in both pathways in WPW syndrome due to mitral annulus calcification (MAC). This case of WPW syndrome type A presented the following conduction abnormalities: (1) right bundle-branch block; (2) transient second-degree AV block with prolonged PR interval of the conducted beats; (3) during electrophysiological study, induction of tachycardia, dependent (phase 3) second-degree AV block, and occasionally conduction of two consecutive beats, the second showing an increased H-V interval (from 25 to 60 ms) and left bundle-branch block (LBBB) pattern, due to (4) infrahisian conduction abnormality.  相似文献   
83.
Audiotape recordings of family interaction samples from 30 nondistressed and 32 multiproblem families were coded for communication deviance (CD). Maternal CD was found to be higher in families high on measures of "preschizophrenic" child behavior, externalizing or "acting out" offspring behavior, overall family distress, and maladaptive marital and family alliance structures. Paternal CD was found to be higher in families in which offspring were rated high on externalizing behaviors.  相似文献   
84.
Summary The costs of the public health and social security system supporting adults 40–50 years old with Down's syndrome during one year (1984) have been investigated in the county of Aarhus, representing about 10% of the Danish population. 77% of the probands live in institutions, the rest in private homes or sheltered residences. The average yearly price of an institutionalized adult is DKr. 237,900 =US$ 21,128 = £ 18,174. If the person lives in a private home, the same figures are DKr. 107,239 =US$ 9,524= 8,393. Average for all probands: DKr. 207,587 = US$18,436 = £ 15,858, which is 127% of a skilled worker's salary.  相似文献   
85.
We investigated the segregation pattern of breast cancer in families with bilateral breast cancer, classifying families with respect to menopausal status (premenopausal versus postmenopausal) and the interval between diagnosis of the two primary tumors in the probands. Probands were "synchronous" if both primaries were diagnosed within 1 year; "asynchronous" if the interval was at least 2 years. Results for four complex segregation analyses are here presented; the findings support heterogeneity in the transmission of breast cancer. In the asynchronous premenopausal-cases-only analysis, a dominant Mendelian gene can explain the breast cancer pattern. A recessive gene is sufficient to describe the breast cancer distribution in the synchronous premenopausal-cases-only analysis. The synchronous all-cases and the asynchronous all-cases analyses add postmenopausal cases of breast cancer to the premenopausal ones, considering any case to be affected. In the asynchronous all-cases analysis, neither the single-locus model nor the mixed model (that is, a major locus plus other factors, genetic and/or cultural) without generation differences in heritability can be rejected by the unrestricted mixed model with generation differences in heritability. For the synchronous all-cases analysis, a mixed model with generation differences in heritability is necessary to explain the breast cancer transmission. Potential sources of error and possible interpretations are discussed.  相似文献   
86.
Cognitive mapping after unilateral temporal lobectomy   总被引:2,自引:0,他引:2  
An investigation of the extension of O'KEEFE and NADEL's [The Hippocampus as a Cognitive Map. Oxford University Press, Oxford 1978] theory of hippocampal functioning is described in patients who have undergone unilateral temporal lobectomy for the relief of epilepsy. A new spatial task, incorporating a recall-for-designs test but based on studies of spatial memory and cognitive mapping in animals was devised. Results supported the prediction of temporal lobe structure involvement in the mediation of non-egocentric but not egocentric space, and of the role of right temporal lobe structures in conditions designed to encourage "place" but not "cue" learning strategies. The role of verbal mediation in task performance is also discussed.  相似文献   
87.
MVP, a Methanococcus jannaschii voltage-gated potassium channel, was cloned and shown to operate in eukaryotic and prokaryotic cells. Like pacemaker channels, MVP opens on hyperpolarization using S4 voltage sensors like those in classical channels activated by depolarization. The MVP S4 span resembles classical sensors in sequence, charge, topology and movement, traveling inward on hyperpolarization and outward on depolarization (via canaliculi in the protein that bring the extracellular and internal solutions into proximity across a short barrier). Thus, MVP opens with sensors inward indicating a reversal of S4 position and pore state compared to classical channels. Homologous channels in mammals and plants are expected to function similarly.  相似文献   
88.
89.
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to within an 8 cM interval on chromosome 17p12-p13. The retinal- specific guanylate cyclase gene (RETGC-1), which maps to within this genetic interval and previously was implicated in Leber's congenital amaurosis, was screened for mutations within this family and in a panel of small families and individuals with various cone and cone- rod dystrophy phenotypes. A missense mutation (E837D) was identified in affected members of the CORD6 family, as well as a second missense mutation (R838C) in three other families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene to be implicated in cone-rod dystrophy and this is the first report of dominant mutations in this gene.   相似文献   
90.
The mere exposure effect was examined in patients with mild to moderate Alzheimer's disease (AD). Twenty patients and 20 elderly controls judged the physical characteristics of faces. Implicit memory was tested later by presenting pairs of faces (old and new) and asking participants which faces they liked better. Patients and controls exhibited above chance preference for previously exposed faces. Experiment 2 evaluated whether the preserved implicit memory of patients was mediated by explicit memory. Patients and controls again judged faces but then later chose which faces they had seen before. Patients exhibited impaired recognition memory compared to controls. These findings suggest that a mere exposure effect for unfamiliar faces is present in mild to moderate AD. The results are discussed in terms of perceptual and conceptual priming and relatively spared occipital lobe functioning in early AD.  相似文献   
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