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Background
AIDS-associated cryptococcal meningitis has a high mortality. Fluconazole was the only systemic antifungal therapy available in our centre. From 1999–2001 we used low-dose fluconazole (200 mg daily initially), and did not offer therapy to patients perceived to have poor prognoses. In 2001 donated fluconazole became available, allowing us to use standard doses (400 mg daily initially). Antiretroviral therapy was not available during the study period. 相似文献996.
Ana Paula Sena Lomba Vasconcelos Alessandra Lamas Granero Lucchetti Ana Paula Rodrigues Cavalcanti Simone Regina Souza da Silva Conde Lidia Maria Gonalves Filipe Rodrigues do Nascimento Ana Cludia Santos Chazan Rubens Lene Carvalho Tavares Oscarina da Silva Ezequiel Giancarlo Lucchetti 《Journal of general internal medicine》2020,35(12):3613
ObjectivesTo assess the attitudes, knowledge, and experiences of Brazilian resident physicians regarding religiosity/spirituality (R/S), factors associated with addressing this issue, and its influence on clinical practice.MethodsWe report results of the multicenter “Spirituality in Brazilian Medical Residents” (SBRAMER) study involving 7 Brazilian university centers. The Network for Research Spirituality and Health (NERSH) scale (collecting sociodemographic data, opinions about the R/S-health interface, and respondents’ R/S characteristics) and the Duke Religion Index were self-administered. Logistic regression models were constructed to determine those factors associated with residents’ opinions on spirituality in clinical practice.ResultsThe sample comprised 879 resident physicians (53.5% of total) from all years of residency with 71.6% from clinical specialties. In general, the residents considered themselves spiritual and religious, despite not regularly attending religious services. Most participants believed R/S had an important influence on patient health (75.2%) and that it was appropriate to discuss these beliefs in clinical encounters with patients (77.1%), although this was not done in routine clinical practice (14.4%). The main barriers to discussing R/S were maintaining professional neutrality (31.4%), concern about offending patients (29.1%), and insufficient time (26.2%). Factors including female gender, clinical specialty (e.g., internal medicine, family medicine, psychiatry) as opposed to surgical specialty (e.g., surgery, obstetrics/gynecology, orthopedics), having had formal training on R/S, and higher levels of R/S were associated with greater discussion of and more positive opinions about R/S.ConclusionBrazilian resident physicians held that religious and spiritual beliefs can influence health, and deemed it appropriate for physicians to discuss this issue. However, lack of training was one of the main obstacles to addressing R/S issues in clinical practice. Educators should draw on these data to conduct interventions and produce content on the subject in residency programs.Electronic supplementary materialThe online version of this article (10.1007/s11606-020-06145-x) contains supplementary material, which is available to authorized users.KEY WORDS: spirituality, religion and medicine, resident physicians, medical education, graduate students, medical residents 相似文献
997.
Characterization and localization of the Gova/b alloantigens to the glycosylphosphatidylinositol-anchored protein CDw109 on human platelets 总被引:1,自引:1,他引:1
The Gova/b alloantigens are expressed on a 175-kD protein (GP175) on human platelets. Anti-Gov alloantibodies have been implicated in posttransfusion purpura and alloimmune neonatal thrombocytopenia. In this report we characterize the immunochemistry of the alloantigens and identify the platelet protein that expresses the Gov epitopes. Approximately 50% of GP175 containing the Gov epitope was released from platelets treated with phosphatidylinositol-specific phospholipase C, indicating that at least some of this protein exists as a glycosylphosphatidylinositol (GPI)-linked isoform. Radioimmunoprecipitation and immunodepletion studies indicated that the Gova/b alloantigens are expressed on the GPI-anchored CDw109 protein. The Gova/b epitopes were expressed on an extracellular, 120-kD soluble fragment (p120) of CDw109 produced by calcium-dependent protease cleavage. Anti-Gov immunoprecipitates of chymotryptic digests of p120 contained 70- and 52-kD fragments of CDw109. Deglycosylation of native CDw109 had no effect on recognition by Gov alloantisera; however, the epitopes were destroyed after exposure to sodium dodecyl sulfate. Gova/b alloantigens were expressed on platelets and PHA-activated T- cells, cultured human umbilical vein endothelial cells, and by many different tumor cell lines, consistent with the tissue distribution of CDw109. 相似文献
998.
Related binding mechanisms for fibrinogen, fibronectin, von Willebrand factor, and thrombospondin on thrombin-stimulated human platelets 总被引:29,自引:2,他引:29
Fibrinogen, fibronectin, von Willebrand factor, and thrombospondin are four large glycoproteins that bind to thrombin-stimulated platelets and influence cellular adhesive functions. The effects of five monoclonal antibodies that react with platelet membrane glycoproteins (GP) IIb and/or IIIa on the binding of these four molecules to stimulated platelets were assessed. Tab and PMI-1, antibodies recognizing GPIIb, had no effect, whereas 10E5 and 2G12, antibodies that immunoprecipitate both GPIIb and IIIa in the presence of calcium, inhibited binding of all four ligands by greater than 85%. T10, an antibody specific for the GPIIb-IIIa complex, produced partial inhibition (60% to 80%) of the binding of each ligand. Inhibitory antibodies were effective in the same dose range for all four proteins and also inhibited binding of fibrinogen, fibronectin, and von Willebrand factor to receptors fixed in an induced state (thrombin-stimulated platelets fixed with paraformaldehyde). Thrombospondin did not bind to these fixed cell preparations. The results suggest that these four adhesive proteins have a related mechanism of binding to thrombin-stimulated platelets. This related mechanism may entail the sharing of some, but not necessarily all, binding sites for the four ligands or a proximal relationship between these binding sites. 相似文献
999.
Mosesson MW; DiOrio JP; Muller MF; Shainoff JR; Siebenlist KR; Amrani DL; Homandberg GA; Soria J; Soria C; Samama M 《Blood》1987,69(4):1073-1081
Release of fibrinopeptide B from fibrinogen by copperhead venom procoagulant enzyme results in a form of fibrin (beta-fibrin) with weaker self-aggregation characteristics than the normal product (alpha beta-fibrin) produced by release of fibrinopeptides A (FPA) and B (FPB) by thrombin. We investigated the ultrastructure of these two types of fibrin as well as that of beta-fibrin prepared from fibrinogen Metz (A alpha 16 Arg----Cys), a homozygous dysfibrinogenemic mutant that does not release FPA. At 14 degrees C and physiologic solvent conditions (0.15 mol/L of NaCl, 0.015 mol/L of Tris buffer pH 7.4), the turbidity (350 nm) of rapidly polymerizing alpha beta-fibrin (thrombin 1 to 2 U/mL) plateaued in less than 6 min and formed a "coarse" matrix consisting of anastomosing fiber bundles (mean diameter 92 nm). More slowly polymerizing alpha beta-fibrin (thrombin 0.01 and 0.001 U/mL) surpassed this turbidity after greater than or equal to 60 minutes and concomitantly developed a network of thicker fiber bundles (mean diameters 118 and 186 nm, respectively). Such matrices also contained networks of highly branched, twisting, "fine" fibrils (fiber diameters 7 to 30 nm) that are usually characteristic of matrices formed at high ionic strength and pH. Slowly polymerizing beta-fibrin, like slowly polymerizing alpha beta-fibrin, displayed considerable quantities of fine matrix in addition to an underlying thick cable network (mean fiber diameter 135 nm), whereas rapidly polymerizing beta-fibrin monomer was comprised almost exclusively of wide, poorly anastomosed, striated cables (mean diameter 212 nm). Metz beta-fibrin clots were more fragile than those of normal beta-fibrin and were comprised almost entirely of a fine network. Metz fibrin could be induced, however, to form thick fiber bundles (mean diameter 76 nm) in the presence of albumin at a concentration (500 mumol/L) in the physiologic range and resembled a Metz plasma fibrin clot in that regard. The diminished capacity of Metz beta-fibrin to form thick fiber bundles may be due to impaired use or occupancy of a polymerization site exposed by FPB release. Our results indicate that twisting fibrils are an inherent structural feature of all forms of assembling fibrin, and suggest that mature beta-fibrin or alpha beta-fibrin clots develop from networks of thin fibrils that have the ability to coalesce to form thicker fiber bundles. 相似文献
1000.
Vinod Jorapur MD Terje K. Steigen MD PhD Christopher E. Buller MD Vladimír Dẑavík MD FRCPC John G. Webb MD Bradley H. Strauss MD PhD Eunice E.S. Yeoh BSc Peter Kurray MD Leszek Sokalski MD Mauricio C. Machado MD Shari S. Kronsberg MS Gervasio A. Lamas MD Judith S. Hochman MD G.B. John Mancini MD 《Catheterization and cardiovascular interventions》2008,72(6):783-789
Objective: To evaluate the distribution and determinants of myocardial perfusion grade (MPG) following late recanalization of persistently occluded infarct‐related arteries (IRA). Background: MPG reflects microvascular integrity. It is an independent prognostic factor following myocardial infarction, but has been studied mainly in the setting of early reperfusion. The occluded artery trial (OAT) enrolled stable patients with persistently occluded IRAs beyond 24 hr and up to 28 days post‐MI. Methods: Myocardial blush was assessed using TIMI MPG grading in 261 patients with TIMI 3 epicardial flow following IRA PCI. Patients demonstrating impaired (0–1) versus preserved (2–3) MPG were compared with regard to baseline clinical and pre‐PCI angiographic characteristics. Results: Impaired MPG was observed in 60 of 261 patients (23%). By univariate analysis, impaired MPG was associated with failed fibrinolytic therapy, higher heart rate, lower systolic blood pressure, lower ejection fraction, LAD occlusion, absence of collaterals (P < 0.01) and ST elevation MI, lower diastolic blood pressure, and higher systolic sphericity index (P < 0.05). By multivariable analysis, higher heart rate, LAD occlusion, absence of collaterals and higher systolic sphericity index (P < 0.01), and lower systolic blood pressure (P < 0.05) were independently associated with impaired MPG. Conclusion: Preserved microvascular integrity was present in a high proportion of patients following late recanalization of occluded IRAs post‐MI. Presence of collaterals was independently associated with preserved MPG and likely accounted for the high frequency of preserved myocardial perfusion in this clinical setting. Impaired MPG was associated with baseline clinical and angiographic features consistent with larger infarct size. © 2008 Wiley‐Liss, Inc. 相似文献