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P J Thompson A Greenough H R Gamsu K H Nicolaides J Philpott-Howard 《Journal of medical microbiology》1992,36(2):117-120
The results of body fluid and surface cultures from 148 preterm infants less than 33 weeks gestational age obtained routinely on admission to a neonatal intensive care unit were reviewed. The aim was to determine the occurrence of congenital bacterial sepsis in this population and to examine whether surface cultures yielded information helpful in management. Gastric aspirate and umbilical, nasal and ear swabs were cultured and the results were compared to those of blood cultures. Nine infants (5.4%) had congenital bacterial sepsis diagnosed by positive blood cultures. Only the results of microscopy of gastric aspirate were available within hours of birth and before the results of blood culture. Microscopy of gastric aspirate, demonstrating pus cells, alone had a sensitivity of 0.86 in predicting congenital sepsis but a specificity of 0.49; the specificity, however, rose to 0.80 if both organisms and pus cells were observed on microscopy. Thus, only this combination was a useful pre-indicator of congenital sepsis. In infants who did not develop septicaemia, treatment was modified only if Streptococcus agalactiae was cultured from surface sites; in all such cases, the organism was grown from the ear swab. Our results demonstrate that congenital bacterial sepsis is common amongst very preterm infants admitted for neonatal intensive care but routine screening of surface cultures should be restricted to an ear swab only. 相似文献
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Normal and diseased isolated lungs: high-resolution CT 总被引:8,自引:0,他引:8
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Promoting clinically effective practice: general practitioners' awareness of sources of research evidence 总被引:3,自引:1,他引:2
Prescott K; Lloyd M; Douglas HR; Haines A; Humphrey C; Rosenthal J; Watt I 《Family practice》1997,14(4):320-323
BACKGROUND: Practitioners are being encouraged to base their clinical
practice on research evidence. In order to do this, they must be aware of
and use the sources of evidence. METHODS: A questionnaire survey was
undertaken to establish GPs' awareness of research evidence in their
clinical practice and, in fundholding practices, its influence on
purchasing plans. Questionnaires were sent to 360 lead fundholders in North
Thames Region and 440 of a random sample of the remaining general
practitioners in the region for comparison. RESULTS: Questionnaires were
returned by 62% of lead fundholders and 63% of GPs in the random sample.
There was limited use of the electronic sources of clinical effectiveness.
There was greater reported awareness of published sources of research
evidence and fundholding GPs were significantly more likely to have
referred to publications summarizing research evidence. CONCLUSIONS: GPs
seem to make more use of published clinical effectiveness sources than the
electronic databases. Consequently, they need educational and technical
support if they are to make full use of the available sources of research
evidence available in other media.
相似文献
6.
Magnetic resonance imaging of the thorax 总被引:2,自引:0,他引:2
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In 260 asbestos-exposed individuals evaluated by means of computed tomography (CT), 43 unsuspected pulmonary masses were found in 27 individuals. The masses included fissural pleural plaques (n = 10), dense fibrotic bands (n = 3), round atelectasis (n = 11), carcinomas (n = 3), and other presumed benign masses (n = 16). The most helpful features in the diagnosis of rounded atelectasis with CT were (a) contiguity to areas of diffuse pleural thickening, (b) a lentiform or wedge-shaped outline, (c) evidence of volume loss in the adjacent lung, and (d) a characteristic "comet tail" of vessels and bronchi sweeping into the margins of the mass. Less advanced areas of focal atelectasis had fewer classic features. Intrafissural pleural plaques were readily identified with high-resolution CT. In asbestos-related masses, the demonstration of stability over time is necessary. Careful interpretation of CT and high-resolution CT features and close surveillance can obviate the need for biopsy in the majority of instances. 相似文献
9.
Liver-infiltrating T helper cells in autoimmune chronic active hepatitis stimulate the production of autoantibodies against the human asialoglycoprotein receptor in vitro. 总被引:2,自引:0,他引:2
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H. L
HR U. TREICHEL T. PORALLA M. MANNS K. H. MEYER ZUM BÜSCHENFELDE B. FLEISCHER 《Clinical and experimental immunology》1992,88(1):45-49
Autoantibodies against the human asialoglycoprotein receptor (ASGPR) occur in the sera of patients with autoimmune liver disorders. Liver-infiltrating T cell clones that specifically recognize the ASGPR have been described in patients with autoimmune chronic active hepatitis (AI-CAH) and primary biliary cirrhosis (PBC). Recently, we have shown that peripheral blood mononuclear cells (PBMC) from patients with AI-CAH or PBC but not chronic viral hepatitis secreted anti-ASGPR antibodies in vitro. In this study we characterized the influence of liver-infiltrating T cells on the secretion of ASGPR-specific autoantibodies by autologous B cells in cell culture supernatants. T cell clones from liver biopsies of three patients with chronic autoimmune liver disorders (one with AI-CAH, two with PBC) were isolated and investigated for their proliferative response to soluble ASGPR and their helper function provided to autoantibody-secreting B lymphocytes. PBMC from these patients secreted autoantibodies spontaneously in their cell culture supernatants and showed a proliferative response to ASGPR. T cell-depleted PBMC, however, lacked spontaneous antibody secretion. Four CD4+CD8- liver-infiltrating T cell clones showed a proliferative response to ASGPR and also induced spontaneous anti-ASGPR antibody production in cell culture supernatants when added to autologous T cell depleted PBMC. Activated supernatants of these T cell clones failed to induce antibody production. None of seven CD4+CD8- and two CD4-CD8+ T cell clones non-responding to ASGPR provided this help for antibody secretion. Anti-ASGPR secretion in vitro could not be inhibited by the addition of MoAbs raised against monomorphic determinants on HLA class II molecules. The addition of purified ASGPR or polyclonal-activating pokeweed mitogen showed no influence on the production of autoantibodies in these cultures. These data show that B lymphocytes require T cell help for the production of ASGPR-specific antibodies. This help can be provided by ASGPR-responsive T helper cells via cellular interactions. 相似文献
10.