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31.
A multiplex PCR was designed to amplify herpes simplex virus types 1 and 2, cytomegalovirus, and varicella-zoster virus DNA present in a diverse range of clinical material. The susceptibility of these viruses to in vivo inhibition by at least one antiviral drug was an important consideration in their inclusion in the multiplex detection system. An aliquot of equine herpesvirus was introduced into each specimen prior to extraction and served as an indicator of potential inhibitors of the PCR and a detector of suboptimal PCR conditions. Compared to virus isolation and immunofluorescence-based antigen detection, the multiplex assay yielded higher detection rates for all viruses represented in the assay. The turnaround time for performance of the assay was markedly reduced compared to those for the other techniques used to identify these viruses. More than 21,000 tests have been performed using the assay. Overall, the multiplex PCR enabled the detection of substantially increased numbers of herpesviruses, in some cases in specimens or anatomical sites where previously they were rarely if ever identified using traditional detection methods.  相似文献   
32.
Many Swedish infants carry Staphylococcus aureus in their intestinal microflora. The source of this colonization was investigated in 50 families. Infantile S. aureus strains were isolated from rectal swabs and stool samples at 3 days and at 1, 2, 4, and 8 weeks of age. The strains were identified by using the random amplified polymorphic DNA method and compared to strains from swab cultures of the mothers' hands, nipples, and nares and from the fathers' hands and nares. Maternal stool samples were also obtained at a later stage to compare infant and adult intestinal S. aureus colonization. Although 60% of 1-month-old children had S. aureus in the stools, this was true of only 24% of the mothers. The median population numbers in colonized individuals also differed: 10(6.8) CFU/g of feces among infants at 2 weeks of age versus 10(3.2) CFU/g of feces in the mothers. Of S. aureus strains in the stools of 3-day-old infants, 90% were identical to a parental skin strain. A total of 96% of infants whose parents were S. aureus skin carriers had S. aureus in their feces and 91% had the same strain as at least one of the parents. In comparison, only 37% of infants to S. aureus-negative parents had S. aureus in the stool samples. Thus, infantile intestinal S. aureus colonization was strongly associated with parental skin S. aureus carriage (P = 0.0001). These results suggest that S. aureus on parental skin establish readily in the infantile gut, perhaps due to poor competition from other gut bacteria.  相似文献   
33.
Major histocompatibility complex class I-restricted CD8(+) cytotoxic T lymphocytes (CTL) are implicated in protective Th1 immunity to Mycobacterium tuberculosis infection. We report the identification of three novel HLA-A*0201-restricted CTL epitopes within mycobacterial superoxide dismutase (SodA), L-alanine dehydrogenase (AlaDH), and L-glutamine synthetase (GlnS) proteins.  相似文献   
34.
35.
A retrospective study was undertaken to assess the value of three-dimensional computed tomography (3-D CT) in evaluating craniofacial abnormalities. Over a 2-year period, 145 children evaluated with routine two-dimensional (2-D) CT had 3-D CT reformatted images assessing a variety of anomalies including craniosynostosis, midface clefts, trauma, and craniofacial syndromes. There were 62 females and 83 males ranging in age from 1 month to 17 years (median: 5 months). Both soft-tissue and bone algorithms were used. In all 145 cases, the 3-D CT images confirmed or provided additional information of depth perception, contours, volumes, and extent of an abnormality. This was especially important and useful in the settings of complex anomalies and preoperative planning. We concluded that 3-D CT reconstructed images in conjunction with routine 2-D CT should be an integral part of the examination in evaluating craniofacial abnormalities.  相似文献   
36.
Human chorionic gonadotrophin (hCG) is present in high concentration in patients with trophoblastic disease. The hCG concentration parallels tumor activity. The first known case of an endogenous binder for hCG in the serum of a patient with trophoblastic disease is reported. The patient's hCG concentration was not detectable when analyzed by a radioimmunoassay using a double antibody method; however, it was positive by a radioimmunoassay using polyethylene glycol precipitation. A high serum blank was also observed in this patient. This led the authors to suspect the presence of an endogenous binder for hCG. Scatchard analysis of the patient's serum revealed a high affinity binder with Ka = 1 x 10(10) M(-1), concentration of binding site = 2 x 10(-11) M. This investigation strongly suggested a specific binder(s) for hCG in the serum of this patient.  相似文献   
37.
Ataxia telangiectasia (A-T) is one of a group of autosomal recessive cerebellar ataxias. Presentation is usually by the age of 2 years and ataxia of both upper and lower limbs develops, such that by early teenage most patients require a wheelchair for mobility. Speech and eye movement are also affected. Other important features are t(7;14) translocations, immunodeficiency, a high serum alpha fetoprotein concentration, growth retardation, telangiectasia-most noticeably on the bulbar conjunctiva-and a very high risk of developing a lymphoid tumour. Patients also show an increased sensitivity to ionising radiation. The classic form of A-T results from the presence of two truncating ATM mutations, leading to total loss of the ATM protein, a protein kinase. Importantly, A-T shows clinical heterogeneity, including milder forms where neurological progression may be slower or of later onset. In these cases there is a correlation between the preservation of neurological function, decreased radiosensitivity, and the degree of retained ATM protein kinase activity. Considerable scope remains for understanding the progress of the disorder in relation to the types of ATM mutation present.  相似文献   
38.
R C Howe  L E Byrd  J L Phillips 《Sleep》1979,1(4):445-449
A method was developed for sequential redistribution of short-duration sleep--waking states into the long-duration behavioral state(s) that surrounds these intervals. This methodological approach is useful in determination of general sleep--waking patterns such as state durations, interstate intervals, and sleep--waking cycles. The redistribution sequences had no effect on total amount of sleep or waking categories, but did decrease stage 1 with successive redistribution steps. Examination of the slope of the curve (number of occurrences or mean epoch duration divided by successive redistributions) can be used to determine the appropriate "smoothing" for electroencephalogram (EEG) state data via location of the breakpoint in the curve. The low-pass redistribution technique has been particularly useful for smoothing large volumes of EEG state data for subsequent analyses without significantly changing the various sleep-waking states.  相似文献   
39.
We report the use of electroconvulsive therapy (ECT) for treatment of a bipolar episode in a mildly retarded young man with cerebral palsy. Difficulties in the diagnosis and treatment of affective disorders in the retarded are discussed.  相似文献   
40.
The precise role of resident alveolar macrophages (AM) in the induction of immune responses to inhaled antigens is not known. In order to gain insight into the immune functions of AM in vivo, the present studies were performed to characterize several immune functional capacities of normal murine AM, to compare these with normal peritoneal macrophages (PM), and to determine the capacity of AM to serve as antigen-presenting cells for the induction of primary antibody-forming cell (AFC) responses to sheep erythrocytes (SRBC) in vitro. We compared the capacities of normal murine AM and of PM to: elaborate interleukin-1 (IL-1), express surface membrane Ia antigen, serve as accessory cells for mitogen-induced blastogenesis, and induce generation of primary AFC responses to SRBC in Mishell-Dutton cultures. We observed that: AM and PM elaborate equivalent IL-1 activity after stimulation with phorbal myristate acetate (PMA); AM "conditioned" with supernatants of concanavilin-A-stimulated spleen cells express surface Ia but do so proportionately less than similarly treated PM; normal AM can serve as accessory cells for mitogen-induced blastogenesis but do so significantly less effectively than do PM; AM substitute poorly for PM with respect to the induction of primary AFC responses to SRBC in standard Mishell-Dutton cultures; however, AM exert potent suppressive activity in these cultures, and this suppression can be reversed by the addition of indomethacin and catalase to cultures, suggesting that both prostaglandins and hydrogen peroxide play suppressive roles; after reversal of suppression in drug-modified Mishell-Dutton cultures, AM can induce primary AFC responses to SRBC but do so less effectively than do similarly treated PM.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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