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41.
Mistakes are inevitable in medicine. To learn how medical mistakes relate to subsequent changes in practice, we surveyed 254 internal medicine house officers. One hundred and fourteen house officers (45%) completed an anonymous questionnaire describing their most significant mistake and their response to it. Mistakes included errors in diagnosis (33%), prescribing (29%), evaluation (21%), and communication (5%) and procedural complications (11%). Patients had serious adverse outcomes in 90% of the cases, including death in 31% of cases. Only 54% of house officers discussed the mistake with their attending physicians, and only 24% told the patients or families. House officers who accepted responsibility for the mistake and discussed it were more likely to report constructive changes in practice. Residents were less likely to make constructive changes if they attributed the mistake to job overload. They were more likely to report defensive changes if they felt the institution was judgmental. Decreasing the work load and closer supervision may help prevent mistakes. To promote learning, faculty should encourage house officers to accept responsibility and to discuss their mistakes. 相似文献
42.
Liver transplantation for chronic hepatitis B with lamivudine-resistant YMDD mutant using add-on adefovir dipivoxil plus lamivudine. 总被引:5,自引:0,他引:5
Chung Mau Lo Chi Leung Liu George K Lau See Ching Chan Irene O Ng Sheung Tat Fan 《Liver transplantation》2005,11(7):807-813
Lamivudine treatment in patients with chronic hepatitis B virus (HBV) infection may improve clinical state and suppress viral replication before liver transplantation. Emergence of lamivudine-resistant YMDD mutant is common. We report the results of liver transplantation in 16 patients with pretransplantation YMDD mutants after receiving lamivudine treatment for a median of 738 days (range, 400-1799 days). Adefovir dipivoxil (10 mg daily) was added on to lamivudine for a median of 20 days (range, 8-271 days) before (n = 11) or at (n = 5) liver transplantation, and the combination was continued indefinitely thereafter. Eight patients received additional intravenous hepatitis B immune globulin (HBIG) for a median of 24 months. Fifteen patients with known pre-adefovir HBV DNA levels had a median titer of 14,200 x 10(3) copies/mL (2 x 10(3) to 4,690,000 x 10(3) copies/mL), and 14 had HBV DNA >10(5) copies/mL. All but 1 patient remained positive for HBV DNA (by quantitative polymerase chain reaction [qPCR]) at the time of liver transplantation, and the titer was greater than10(5) copies/mL in 8 patients. The median follow-up after liver transplantation was 21.1 (range, 4.4-68.9) months. One patient (6%) died of an unrelated cause 12.2 months after transplantation, and 15 patients (94%) were alive with the original graft. All patients cleared HBV DNA and had no detectable HBV DNA by qPCR at the latest follow-up. Fourteen patients had cleared hepatitis B surface antigen (HBsAg), but 2 patients who received only adefovir dipivoxil and lamivudine without HBIG remained HBsAg positive after 7.7 and 9.5 months. Serum HBV DNA, however, was negative, and there was no biochemical or histological evidence of recurrence. Adefovir dipivoxil was well tolerated with no significant renal toxicity. In conclusion, a combination of add-on adefovir dipivoxil plus lamivudine therapy provides effective prophylaxis in patients with pretransplantation YMDD mutant that may be actively replicating. The cost effectiveness of additional passive immunoprophylaxis remains to be defined. 相似文献
43.
44.
Effects of captopril on hemodynamics and blood gases in chronic obstructive lung disease with pulmonary hypertension 总被引:2,自引:0,他引:2
L Bertoli S Lo Cicero I Busnardo G Rizzato G Montanari 《Respiration; international review of thoracic diseases》1986,49(4):251-256
The effects of Captopril, an angiotensin-converting enzyme inhibitor, on pulmonary hemodynamics and blood gases were studied in 9 patients with chronic obstructive lung disease (COLD) and pulmonary hypertension (PA-P greater than 20 mm Hg). Hemodynamic data were recorded prior to Captopril administration (50 mg per os) and for the next 60 min. Following Captopril administration, significant reductions in mean pulmonary artery pressure (PA-P) (p less than 0.05), in mean pulmonary wedge pressure (PW-P) (p less than 0.05), and in total pulmonary resistance (TPR) were noted; significant reductions in mean brachial artery pressure (BA-P) and systemic vascular resistance (SVR) were also recorded, while cardiac output, heart rate and blood gas tensions showed no significant changes. Furthermore, the higher the hypoxemia, the greater was the reduction in BA-P (p less than 0.05). We therefore feel that Captopril, when administered to COLD patients with pulmonary hypertension, may protect the pulmonary circulation from hypoxic pulmonary vasoconstriction. 相似文献
45.
46.
A Ioli D Forino L Lo Giudice A Staiti R Dollenz M Allegra G Magaraci P Bramanti 《Acta neurologica》1992,14(3):215-219
The AA. refer on the first Italian case of amoebae "Limax" primitive myelitis in a 25-year-old man. Microscopical observation showed amoebae free-living, but their cultivation and identification were not possible. The patient recovered because of the propriety of diagnosis and therapy with amphotericin B. 相似文献
47.
A simple and rapid method for the simultaneous determination of 11 metals (As, Be, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, and Zn) in urine by inductively coupled argon plasma-atomic emission spectrometry is presented. Acidification of the urine was the only sample preparation required. Background correction was applied to ensure accuracy. Analytical calibration was based on matrix matching using a "simulated urine" solution. Detection limits in the low mg/L range and linearity over three orders of magnitude were obtained for all 11 metals. In the Occupational Health Laboratory, this procedure has been applied for routine screening of workers for occupational exposure to toxic metals. 相似文献
48.
Demonstration of an antigen common to several varieties of neoplasia 总被引:21,自引:0,他引:21
49.
Dr. David Lo Christina R. Reilly Linda C. Burkly Jenefer DeKoning Terri M. Laufer Laurie H. Glimcher 《Immunologic research》1997,16(1):3-14
Ten years ago, we proposed a model for thymus function in which thymic epithelial cells are primarily responsible for imprinting
major histocompatibility complex (MHC)-restricted specificity, and bone marrow-derived macrophages or dendritic cells are
responsible for the induction of self-tolerance. Since then, transgenic and knockout models have allowed for a dissection
of thymic stromal components in vivo, leading to a new understanding of their specialized functions. We have determined that
with regard to class II-restricted CD4 T-cell development, two distinct subsets of thymic epithelium help shape the repertoire:
Cortical epithelium appears solely responsible for positive selection, whereas a fucose-bearing subset of medullary epithelium
is specialized for negative selection. This absolute separation of positive and negative selection into two distinct spatial
and temporal compartments leads to a much simpler view of the process of repertoire selection. Finally, a novel view of the
function of the thymic medulla is discussed. 相似文献
50.
Summary. Nested polymerase chain reaction (PCR) amplifying the morphological transforming region II (mtrII) of cytomegalovirus (CMV)
has been shown to be useful in the detection of CMV DNA in bone marrow transplant (BMT) recipients. However, there has never
been any report on mutation hot spots and subtypes of this open reading frame. Using primers derived from sequences upstream
and downstream of mtrII (ORF 79), CMV DNA from peripheral blood leukocytes (PBL) and conventional CMV culture of 16 BMT recipients
were amplified by PCR, cloned into pUC118, and sequenced. The amino acid sequences were predicted using the standard triplet
code. The DNA sequences obtained from direct amplification of CMV in PBL obtained from the 16 patients were 100% identical
to the corresponding ones obtained by amplification of CMV DNA extracted from conventional CMV culture. Within mtrII (ORF
79), hot spot single base mutations were observed at positions +40 (G→A), +123 (A→G), +213 (T→C), and +219 (T→C). However,
because of third base degeneracy, only amino acid 14 was changed from valine to isoleucine in the predicted protein of 13
patients. This corresponded to the hot spot mutation at position +40 (GTC→ATC), while the rest were silent mutations. An insertion
of 3 bases (ACG) was observed in the CMV DNA of 10 patients at positions +91 to +93, leading to a threonine insertion at amino
acid 31 in these patients. For patient no. 147 there was a 65 bp deletion in the CMV DNA amplified later in the course of
BMT as compared with that early in the course. This gave rise to a frame shift mutation and a change of more than 70% in the
predicted amino acid sequence of the protein.
Accepted October 14, 1998 Received May 20, 1998 相似文献