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991.
OBJECTIVE: To compare the predictive value of intrapartum fetal pulse oximetry to that of fetal scalp blood pH for an abnormal neonatal outcome in the case of thick meconium. STUDY DESIGN: A prospective multicenter observational study was performed from June 1994 to November 1995. Fetal oxygen saturation was monitored using a Nellcor N-400 fetal pulse oximeter in case of abnormal FHR. The last readings of fetal oxygen saturation and fetal scalp blood pH before birth were used to assess the ability of both techniques to predict an abnormal neonatal status. RESULTS: At a 30% cutoff, the negative predictive value of fetal oxygen saturation was not altered in case of meconium when compared to clear amniotic fluid (79 and 83%, respectively). Fetal scalp blood pH at a 7.20 threshold had a poor negative predictive value in case of meconium when compared to clear amniotic fluid (56% versus 88%, respectively). The receiver operator characteristic curve showed similar performance of fetal scalp blood pH and pulse oximetry in cases with clear amniotic fluid. In cases with meconium, the performance of fetal scalp blood pH was poor, whereas that of pulse oximetry remained unchanged. In three cases with meconium below the vocal cords, a drop in fetal oxygen saturation was observed during labor whereas fetal scalp blood pH remained within normal values. CONCLUSION: The predictive value of fetal scalp blood pH is poor in case of meconium, whereas the predictive value of pulse oximetry seems to be unchanged in this situation.  相似文献   
992.
993.
Chronic invasive fungal sinusitis: a report of two atypical cases   总被引:4,自引:0,他引:4  
The purpose of this article is to describe a chronic variant of invasive fungal sinusitis (IFS) and discuss its management. This is a retrospective review of two cases of IFS that were characterized by atypical clinical courses. Patient 1 was a 75-year-old man with noninsulin-dependent diabetes mellitus who came to us with a 5-month history of headache. Computed tomography detected an opacified left sphenoid sinus. After the man failed to respond to medical therapy, he underwent a left endoscopic sphenoidotomy. Pathologic examination revealed that septate, branching fungal hyphae had invaded the soft tissues. The patient was started on oral itraconazole, but later switched to intravenous amphotericin B in response to intracranial extension. The man's disease stabilized, but he died a little more than 1 year later of unrelated causes. Patient 2 was an otherwise healthy 41-year-old woman who came to us with nasal congestion and unilateral nasal polyps. She underwent endoscopic sinus surgery. Pathologic examination identified granulomatous sinusitis and septate, branching fungal hyphae that had invaded the soft tissue of the middle turbinate. The patient was not treated with systemic antifungal medications because of the localized nature of the fungal invasion and the lack of bone invasion or erosion. She has now been symptom-free for 5 years. These two cases demonstrate that IFS can appear in a chronic variant form that is characterized by an indolent course and histologic evidence of tissue invasion by fungal hyphae. The type of treatment is dependent on the extent of the disease on initial examination and the rapidity of its progression.  相似文献   
994.
The accompanying multivariate analysis of the binding profiles of antiparkinson agents revealed contrasting patterns of affinities at diverse classes of monoaminergic receptor. Herein, we characterized efficacies at human (h)D(2SHORT(S)), hD(2LONG(L)), hD(3), and hD(4.4) receptors and at halpha(2A)-, halpha(2B)-, halpha(2C)-, and halpha(1A)-adrenoceptors (ARs). As determined by guanosine 5'-O-(3-[(35)S]thio)triphosphate ([(35)S]GTPgammaS) binding, no ligand displayed "full" efficacy relative to dopamine (100%) at all "D(2)-like" sites. However, at hD(2S) receptors quinpirole, pramipexole, ropinirole, quinerolane, pergolide, and cabergoline were as efficacious as dopamine (E(max)100%); TL99, talipexole, and apomorphine were highly efficacious (79-92%); piribedil, lisuride, bromocriptine, and terguride showed intermediate efficacy (40-55%); and roxindole displayed low efficacy (11%). For all drugs, efficacies were lower at hD(2L) receptors, with terguride and roxindole acting as antagonists. At hD(3) receptors, efficacies ranged from 33% (roxindole) to 94% (TL99), whereas, for hD(4) receptors, highest efficacies (approximately 70%) were seen for quinerolane, quinpirole, and TL99, whereas piribedil and terguride behaved as antagonists and bromocriptine was inactive. Although efficacies at hD(2S) versus hD(2L) sites were highly correlated (r = 0.79), they correlated only modestly to hD(3)/hD(4) sites (r = 0.44-0.59). In [(35)S]GTPgammaS studies of halpha(2A)-ARs, TL99 (108%), pramipexole (52%), talipexole (51%), pergolide (31%), apomorphine (16%), and quinerolane (11%) were agonists and ropinirole and roxindole were inactive, whereas piribedil and other agents were antagonists. Similar findings were obtained at halpha(2B)- and halpha(2C)-ARs. Using [(3)H]phosphatidylinositol depletion, roxindole, bromocriptine, lisuride, and terguride displayed potent antagonist properties at halpha(1A)-ARs. In conclusion, antiparkinson agents display diverse agonist and antagonist properties at multiple subtypes of D(2)-like receptor and alpha(1)/alpha(2)-AR, actions, which likely contribute to their contrasting functional profiles.  相似文献   
995.
996.
Centrocytes in germinal centers on selection differentiate into plasma cells and/or memory B cells. Cells that have acquired autoreactivity by somatic mutation generally fail to undergo positive selection and die by apoptosis. Presence of isotype-switched high-affinity autoantibodies in serum of autoimmune patients suggests that autoreactive plasma cells eventually emerge from a germinal center reaction. Currently, it is still unclear to which extent the same is true for autoreactive memory B cells. To address this question, we have analyzed whether IgG-bearing memory B cells with specificity for thyroid peroxidase (TPO) can be found in blood of patients with autoimmune thyroid disease and in normal blood donors. Autoreactive TPO-specific IgG+ memory B cells were identified using a previously described assay combining two-step immunomagnetic enrichment with flow cytometric detection. Autoreactive IgG+ memory B cells were found in 65% of the patients with autoimmune thyroid disease and in 17% of normal blood donors; 40% of the latter had no detectable TPO-specific IgG in the serum. The specificity of enriched TPO-specific IgG+ memory B cells was confirmed by in vitro proliferation and differentiation into antibody-secreting cells at limiting dilution and analysis of the supernatants for the presence of TPO-specific IgG. Detection of TPO-specific IgG+ memory B cells in most patients with clinically manifested autoimmune thyroid disease and few normal blood donors may argue for a role of circulating memory B cells in onset of disease.  相似文献   
997.
Generation and use of alternative multimers of peptide/MHC complexes   总被引:3,自引:0,他引:3  
For many years, the detection of antigen-specific T cells has relied on indirect in vitro assays such as cytokine secretion, proliferation or chromium release assays. Things have dramatically changed during the past few years, thanks to the imagination of several investigators who have developed very elegant strategies to produce multivalent peptide/MHC complexes. One of these strategies has been to produce peptide-loaded monomeric biotinylated MHC molecules, which could be obtained as tetramers upon incubation with tetravalent streptavidin. Although this latter approach has been by far the most popular, this review focuses on other strategies which have also been successful.  相似文献   
998.
The distributions of the antibiotic resistance patterns in a population of Staphylococcus aureus isolates from a teaching hospital were studied over a 9-year period. The results indicate the existence of successive major epidemic methicillin-resistant strains and the emergence of a methicillin-susceptible strain with an unusual resistance pattern. Our findings suggest that this methicillin-susceptible S. aureus strain could be derived from the dominant gentamicin-susceptible methicillin-resistant S. aureus strain with the loss of a 40-kb DNA fragment.  相似文献   
999.
Kaposi's sarcoma herpesvirus (KSHV) is linked causally to Kaposi's sarcoma. Epidemiological studies have shown that KSHV transmission can occur during sex among homosexual men, but heterosexual transmission seems to be very rare in KSHV low prevalence countries. A seroepidemiological study was conducted to determine whether KSHV is transmitted sexually between heterosexuals in an endemic country. Sera from 282 subjects of African origin living in Djibouti were tested for antibodies to KSHV and HIV-1. Among the 282 individuals, 43 were female prostitutes working in the streets (group 1), 123 were female prostitutes working in luxury bars (group 2), 41 were non-prostitute females (group 3), and 75 were non-prostitute males (group 4). KSHV seroprevalence was 26, 20, 17, and 36% in groups 1, 2, 3, and 4, respectively. The seroprevalence of KSHV is not different between street or bar prostitutes and non-prostitute females (OR = 1.67; P = 0.34 and OR = 1.18; P = 0.73). These results suggest that in this endemic country commercial sex work does not seem to be a risk factor for KSHV infection and provides evidence against heterosexual transmission of KSHV in the female population studied.  相似文献   
1000.
The signaling network of the high-affinity receptor for IgE in mast cells involves tyrosine phosphorylation of a number of proteins. Here we report evidence that phospholipid scramblase, a protein involved in the distribution of phospholipids between the two leaflets of the plasma membrane, is a target for tyrosine kinases in this signal. The implication of this observation is briefly discussed.  相似文献   
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