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91.
The patient presented with the typical features of Down syndrome: hypotonia, brachycephaly, flattened occiput, bilateral prominent medical epican-thic folds, flat nasal bridge, protruding tongue, low-set dysplastic ears, short broad hands, bilateral clinodactyly and simian crease. The karyotype of this child was originally reported as normal. High-resolution chromosomes revealed extra material on the long arm of chromosome 18. The mother's karyotype showed a reciprocal translocation between the long arm of 18 and the long arm of 21 at band q23 and q22.1, respectively. FISH performed separately with two different 21q cosmid probes gave two signals on the mother's metaphases and three signals on the prob-and. These findings confirmed that the proband is trisomic for the long arm of chromosome 21 at loci D21S65 and D21S19.  相似文献   
92.
A pilot study is reported of HLA-A, B, and C antigens in 141 East African Blacks comprising patients with Burkitt's lymphoma or nasopharyngeal carcinoma, either with active disease or in long-term remission, together with comparable controls. This study forms part of a wider program investigating host factors in these diseases. A protocol was selected for optimal testing of cells processed and cryopreserved between 1972 and 1976, largely under field conditions, which employed a two-color fluorochromasia typing procedure. Antigen distribution and computed haplotype frequencies in the total unrelated population are given. New findings include an approximately equal frequency of Aw23 and Aw24, a high (18%) incidence of Bw21, and the gametic associations of Aw36 with Bw44, and Aw30 with Bw45. Of the major group of B15-related antigens reported earlier, SV is the most common, and there are strong linkages of SV with Cw2 and Bw with Cw3. The possible presence of further variants at the A- and B-loci is reported. The proportion of B-locus antigen “blanks” in this study is 5.9%. Relationships have been sought between the HLA antigens and diseases studied: the antigen A29, possibly in linkage with Bw42, shows a correlation with disease susceptibility, and associations are suggested between Bw44 (in possible combination with Aw36) and resistance to both BL and NPC, and between Bw45 and long-term remission in NPC.  相似文献   
93.
Neural origins of the P300   总被引:13,自引:0,他引:13  
A review of the literature investigating the neural origins of detection behavior in humans reveals two event-related potential components, P3a and P3b, each with a distinct neural organization and cognitive function.The P3a is involved in automatic novelty detection and characterized by a more anterior cortical distribution, whereas the P3b is concerned with volitional target detection and has a more posterior cortical distribution. Intracranial investigation, studies with patients with focal brain lesions, and functional neuroimaging (fMRI) studies converge with scalp-recorded event-related potential (ERP) data in suggesting that a widespread cortical network gives rise to both automatic and controlled detection behavior. The main regions consistently attributed to generating detection-related brain activation include the temporal-parietal junction, medial temporal complex, and the lateral prefrontal cortex. The extant human and animal literature addressing the neural networks, neuropharmacological underpinnings, and behavioral significance of the P300 potential will be reviewed.  相似文献   
94.
95.
Silent partners: the wives of sleep apneic patients   总被引:2,自引:1,他引:2  
R D Cartwright  S Knight 《Sleep》1987,10(3):244-248
The wives of 10 male patients being treated for sleep apnea, obstructive type, were interviewed and given the Social Adjustment Scale (SAS) and Marital Satisfaction Inventory (MSI). The patients also completed an SAS and a Minnesota Multiphasic Personality Inventory (MMPI). These data were compared with those from a sample of divorced patients from the same pool. The married patients were significantly more depressed and socially isolated than were those divorced. Both marital partners showed poor adjustment in the Marital and Social/Leisure areas, and patients also showed poor adjustment in their Parental Role. Marriages do not necessarily represent social support but appear to be an added burden for sleep apneic patients.  相似文献   
96.
The minimum inhibitory concentration (m.i.c.) of kitasamycin, tylosin and tiamulin for Mycoplasma gallisepticum (Mg) were compared with 10(6), 10(4), and 10(2) CFU/ml of the organisms with the drug incorporated in mycoplasma agar. The lowest m.i.c. was obtained with tiamulin and the highest with kitasamycin and, in general, the m.i.c.'s were directly influenced by the concentration of mycoplasmas. Chick embryos at 19 days of incubation were infected with Mg and the hatched infected chicks were used for comparing the protective effect of the three drugs. They were given in the drinking water when the chicks were 2, 3 and 4 days of age. Weight gains for the infected treated birds were similar for all three drugs; they were significantly lower than for those of uninfected chicks and significantly higher than for those of untreated infected chicks. However Mg could be isolated from a high proportion of chicks in the infected treated and untreated groups at 32 days of age.  相似文献   
97.
The injection of neonatal rabbits of genotype a1n8 1g7 4/a2n8 2f71g75with anti-n81 antiserum suppressess the expression of the paternal f73 and g74 IgA allotypes; the expression of the maternal 171 IgA allotype is enhanced but the expression of the g75 allotype is not significantly enhanced. The concentrations of these allotypes in serum correlated with the immunofluorescent analyses of cellular ratios in gut sections. Allotype suppression of IgA with an anti-IgM reagent supports the concept that the IgM bearing cells are the precursors of the IgA secreting cells.  相似文献   
98.
99.
Cytogenetic studies of patients with therapy-induced acute myeloid leukemia (t-AML) have demonstrated whole chromosome loss or q-arm deletion of chromosomes 5 and/or 7 in a majority of cases. We have established two cell lines, SAML-1 and SAML-2, from two patients who developed t-AML after radiation and chemotherapy for Hodgkin disease. In both cases, the leukemia cells contained 5q deletions. SAML-1 has 58 chromosomes and numerous abnormalities, including der(1)(1qter-->1p22::5q31-->5qter), der(5)(5pter-->5q22::1p22-->1pter), +8, der(13)i(13)(q10)del(13)(q11q14.1), and t(10;11). Fluorescence in situ hybridization (FISH) with unique sequence probes for the 5q31 region showed loss of IL4, IL5, IRF1, and IL3, and translocation of IL9, DS5S89, EGR1, and CSFIR to 1p. SAML-2 has 45 chromosomes, del(5)(q11.2q31) with a t(12;13)ins(12;5), leading to the proximity of IRF1 and RB1, and complex translocations of chromosomes 8 and 11, resulting in amplification of MYC and MLL. Comparative genomic hybridization and spectral karyotyping were consistent with the G-banding karyotype and FISH analyses. Because a potential tumor suppressor(s) in the 5q31 region has yet to be identified, these cell lines should prove useful in the study of the mechanisms leading to the development of t-AML.  相似文献   
100.
Ionic liquids (ILs) can be used for embalming and tissue preservation. ILs does not cause tissue damage and the tissue colour remains unaltered after treatment. Microscopical morphology of tissues fixed in ILs is of better quality than that of tissues fixed in formalin. Tissue preservation depends on the type of ILs. Best results were obtained with 1-methyl-3-octyloxymethylimidazolium tetrafluoroborate, the density of which resembles that of water. The salt is nonvaporous and when used as a formalin substitute, it eliminates health hazards in the pathological laboratory.  相似文献   
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