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991.
This paper describes an 8-year-old girl with Klippel-Feil syndrome (KFS) associated with frontonasal dysplasia, Sprengel deformity and postaxial polydactyly. These findings are tentatively explained on the basis of a single mutant gene for KFS with broad action in the morphogenesis of the skeletal system. 相似文献
992.
Dr. P. Zöpel 《Journal of basic microbiology》1982,22(9):661-670
Dipyridamole at a concentration of 50 μM/ml displays no activity on adsorption and penetration of pseudorabies virus in chicken embryonal cells. Furthermore, first stages of virus replication take place within the nucleus, whereas incomplete virus cores defective in DNA content are found within the nucleoplasm at times when the regular viral replication has been finished in controls. Defective pseudorabies virus particles lacking in DNA-content of the core, can be observed at the end of normal replication time. Consequently, the antiviral activity of dipyridamole may be due to blocking of the synthesis or of the incoporation of infectious viral DNA into the virus core. 相似文献
993.
Cells that mediate NK like cytotoxicity are present in the human delayed type hypersensitivity response. 下载免费PDF全文
D Tartof C W Yung J J Curran C Livingston Z Thalji 《Clinical and experimental immunology》1984,58(2):462-469
By inducing delayed type hypersensitivity (DTH) responses under previously formed skin blisters we determined that cells which mediate natural killer (NK) like cytotoxicity are present in the DTH response in man. Similar levels of killing were not present in cells obtained from skin blisters not associated with positive DTH responses. The DTH response associated killer cell was found to be a mononuclear cell that had presumably undergone stimulation since it not only killed NK sensitive K-562 cells, but also NK resistant Daudi target cells. 相似文献
994.
Identification of histiocytic reticulum cells by the immunohistochemical demonstration of factor XIII (F-XIIIa) in human lymph nodes 总被引:2,自引:0,他引:2
Morphologically and enzyme histochemically distinguishable tissue macrophages and stromal cells of human reactive lymph nodes were characterized by the cytoplasmic presence of the subunit A of factor XIII and by the expression of surface antigenic determinants reacting with monoclonal antibodies directed against monocyte/macrophage populations (Mo 1, Leu M3) and HLA-DR antigens. The distribution of F-XIIIa positive cells was studied on formaldehyde-fixed paraffin-embedded sections with immunoperoxidase techniques. established on cryostat section with double immunofluorescence. Alpha-Naphthyl acetate esterase (ANAE) reaction was The immunophenotype was established on cryostat sections with double immunofluorescence. Alpha-Naphthyl acetate esterase (ANAE) reaction was carried out on these cryostat sections to identify tissue macrophages. The antibody against F-XIIIa detected histiocytes in both intra- and extra-sinusoidal locations which were ANAE+, Mo 1+, Leu M3+ and HLA-DR-. F-XIIIa was also present in fibroblast-like mesenchymal cells with the following phenotypic characteristics: ANAE-, Mo 1+, Leu M3+ and HLA-DR+. The anti F-XIIIa antibody did not stain lymphoid cells, granulocytes, epithelial cells, endothelial cells and mast cells. The immunohistochemical detection of F-XIIIa works on formaldehyde-fixed paraffin-embedded sections. The most promising application seems to be the identification of histiocytes in lymphoid and histiocytic proliferations. 相似文献
995.
Enhanced vascular permeability and haemorrhage-inducing activity of rabbit C5ades arg: probable role of polymorphonuclear leucocyte lysosomes. 总被引:10,自引:2,他引:10 下载免费PDF全文
We previously reported that the injection into rabbit skin of rabbit zymosan-activated plasma (ZAP) induces marked polymorphonuclear leucocyte (PMN) infiltration, a transient increase in vascular permeability (1 hr) and prolonged red blood cells extravasation lasting at least 10 hr. Here we describe the fractionation of ZAP to identify the factor(s) responsible for these effects. On CM Sephadex G-25 chromatography, the majority of the leucocyte-attracting, permeability-enhancing and haemorrhage-inducing activities eluted in the high-salt fractions (0 . 6 M ammonium formate, 1 M NaCl pH 5 . 0), suggesting that this is a very basic molecule(s). Furthermore, the three activities eluted in the same fraction on Sephadex G-100, with an apparent molecular weight of 14,000--17,000 daltons. These observations, and the previously described requirement for C5 in the plasma, suggest that C5ades arg is the active factor. Experiments performed in neutropenic rabbits indicated that PMN are required for both the increase in permeability and red cell extravasation. Ultrastructural studies showed extensive degenerative changes in the infiltrating PMNs evident even in 1--2-hr lesions. These ranged from 'watery' cytoplasm, loss of glycogen and cell membrane to segregation and extensive extracellular release of lysosomes. It is postulated that C5ades arg-induced chemotaxis and metabolic perturbations contribute to this rapid degeneration of the PMNs, and that the release of lysosomes from these cells results in progressive vascular injury. 相似文献
996.
Clinical immunity in acute gastroenteritis caused by Norwalk agent. 总被引:31,自引:0,他引:31
T A Parrino D S Schreiber J S Trier A Z Kapikian N R Blacklow 《The New England journal of medicine》1977,297(2):86-89
To examine immunity in viral gastroenteritis, we challenged and then rechallenged 12 volunteers with Norwalk agent and evaluated symptoms, jejunal biopsies and serum antibody. With the first challenge, gastroenteritis developed in six volunteers but not in the others. When rechallenged 27 to 42 months later, the six who became ill initially again had gastroenteritis with jejunal lesions; in the six previously immune volunteers illness or jejunal lesions did not develop. Four of five ill volunteers had increases in serum antibody to Norwalk agent after both challenges. Serum antibody did not increase in three immune volunteers after either challenge. Four volunteers who had twice become ill underwent a third challenge four to eight weeks after their second illness. In one gastroenteritis developed; in three, it did not. These findings indicate two forms of immunity for viral gastroenteritis, one of short and the other of long duration. Factors other than serum antibody appear important in immunity to Norwalk gastroenteritis. 相似文献
997.
Adaptive changes in early and late blind: a FMRI study of verb generation to heard nouns 总被引:10,自引:0,他引:10
Literacy for blind people requires learning Braille. Along with others, we have shown that reading Braille activates visual cortex. This includes striate cortex (V1), i.e., banks of calcarine sulcus, and several higher visual areas in lingual, fusiform, cuneus, lateral occipital, inferior temporal, and middle temporal gyri. The spatial extent and magnitude of magnetic resonance (MR) signals in visual cortex is greatest for those who became blind early in life. Individuals who lost sight as adults, and subsequently learned Braille, still exhibited activity in some of the same visual cortex regions, especially V1. These findings suggest these visual cortex regions become adapted to processing tactile information and that this cross-modal neural change might support Braille literacy. Here we tested the alternative hypothesis that these regions directly respond to linguistic aspects of a task. Accordingly, language task performance by blind persons should activate the same visual cortex regions regardless of input modality. Specifically, visual cortex activity in blind people ought to arise during a language task involving heard words. Eight early blind, six late blind, and eight sighted subjects were studied using functional magnetic resonance imaging (fMRI) during covert generation of verbs to heard nouns. The control task was passive listening to indecipherable sounds (reverse words) matched to the nouns in sound intensity, duration, and spectral content. Functional responses were analyzed at the level of individual subjects using methods based on the general linear model and at the group level, using voxel based ANOVA and t-test analyses. Blind and sighted subjects showed comparable activation of language areas in left inferior frontal, dorsolateral prefrontal, and left posterior superior temporal gyri. The main distinction was bilateral, left dominant activation of the same visual cortex regions previously noted with Braille reading in all blind subjects. The spatial extent and magnitude of responses was greatest on the left in early blind individuals. Responses in the late blind group mostly were confined to V1 and nearby portions of the lingual and fusiform gyri. These results confirm the presence of adaptations in visual cortex of blind people but argue against the notion that this activity during Braille reading represents somatosensory (haptic) processing. Rather, we suggest that these responses can be most parsimoniously explained in terms of linguistic operations. It remains possible that these responses represent adaptations which initially are for processing either sound or touch, but which are later generalized to the other modality during acquisition of Braille reading skills. 相似文献
998.
TT-virus (TTV, patient initials: T.T.), a novel DNA virus, was first isolated in Japan in 1997 from serum of a patient with post-transfusion hepatitis of unknown aetiology. To date, the contribution of TTV to liver disease remains doubtful. The potential for transmission via blood and blood products makes it essential to establish the prevalence of TTV viraemia in the blood donor population. 413 blood donor serum samples were chosen randomly, the DNA was extracted and TTV-specific DNA amplified by nested polymerase chain reaction (PCR). TTV infection was present in 13 out of 413 (3.15%) blood donors in the Auckland region of New Zealand using a set of primers targeting open reading frame (ORF) 1. These 13 amplification products (264 bp) were sequenced and TTV genotypes determined. Alignment with published TTV sequences showed that seven (53.8%) of the thirteen positive serum samples belonged to genotype 1, five (38.5%) belonged to genotype 2 and one (7.7%) could not be classified as either genotype 1 or 2. One hundred twenty-seven blood donor serum samples were retested with a second set of primers targeting the 5' region of the TTV genome in a single round PCR. Forty-three samples were positive for TTV DNA with these primers resulting in a prevalence of 37%. The data demonstrate that TTV is present among New Zealand blood donors and support the need for further investigation into the natural history of TTV infection. 相似文献
999.
1000.
GABA- and glutamate-mediated synaptic potentials in rat dorsal raphe neurons in vitro 总被引:1,自引:0,他引:1
1. Synaptic potentials were recorded with intracellular electrodes from rat dorsal raphe neurons in a slice preparation. 2. Synaptic potentials were evoked by applying electrical pulses to bipolar stimulating electrodes positioned immediately dorsal to the raphe nucleus; these arose after a latency of 0.5-5 ms and had a duration of 20-200 ms. 3. The synaptic potential was biphasic (at the resting potential) when the recording electrodes contained potassium citrate; a depolarization was followed by a hyperpolarization. The hyperpolarization reversed in polarity at -70 mV and was blocked by bicuculline. 4. The depolarizing synaptic potential was reduced to 50-90% of control by kynurenate (1-2 mM) or 6-cyano-2,3-dihydroxy-7-nitro-quinoxaline (CNQX) (10 microM) and increased in amplitude and duration by magnesium-free solution. 5. In magnesium-free solutions (with CNQX), the depolarizing synaptic potential was blocked by DL-2-amino-5-phosphonovaleric acid (APV, 50 microM). APV also blocked depolarization caused by adding N-methyl-D-aspartate (NMDA) to the superfusion solution. 6. The results indicate that raphe neurons display two synaptic potentials having a duration of 150-200 ms: one that is mediated by GABA and a second that is due to an excitatory amino acid. The component mediated by an excitatory amino acid involves, in part, a receptor of the NMDA type. 相似文献