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91.

BACKGROUND:

There is little literature regarding how a gastroenterology trainee affects a patient’s interpretation of care during outpatient clinic visits. Improving patient satisfaction is desirable and benefits may include enhanced patient compliance as well as providing trainees with areas for improvement.

OBJECTIVES:

To evaluate patient satisfaction in an outpatient gastroenterology clinic when seen by a trainee and attending physician versus an attending physician alone. The secondary objective was to evaluate physician characteristics that play a role in creating a positive clinical experience.

METHODS:

A randomized prospective survey study was conducted over an 11-month period (July 2012 to June 2013) at St Boniface Hospital (Winnipeg, Manitoba). Two gastroenterology fellows (postgraduate year 4 and 5) and nine internal medicine residents (postgraduate year 1 to 3) comprised the ‘trainee’ role, while three academic clinicians comprised the ‘attending’ role. Patients included individuals seen for an initial consultation and were >18 years of age.

RESULTS:

A total of 211 patients comprised the final study group, with 118 in the attending group and 93 in the trainee group. In univariate analysis, patients more often had a very good experience when seen by an attending physician alone versus a trainee and attending physician (73% versus 56%; P=0.016); however, on multivariate analysis, there was no significant difference in patient satisfaction (OR 0.89; P=0.931). Physician factors found to be associated with high patient satisfaction on multivariate analysis included: addressing all patient concerns (OR 27.56; P=0.021); giving the patient a preliminary diagnosis (OR 78.02; P=0.006); and feeling the physician was thorough (OR 72.53; P=0.029).

CONCLUSIONS:

The present study did not reveal a difference in patient satisfaction if a patient sees an attending physician alone or with a trainee. Moreover, to improve patient satisfaction in a gastroenterology clinic, physicians should address all patient concerns, provide a preliminary diagnosis and appear to be thorough in their assessment. Further work to increase patient awareness on the role of residents in teaching hospitals is warranted to further promote careers in gastroenterology.  相似文献   
92.
93.
Expression and structure of CD22 in acute leukemia   总被引:1,自引:0,他引:1  
Boue  DR; LeBien  TW 《Blood》1988,71(5):1480-1486
The purpose of this study was to examine the expression and structure of CD22 in B cell precursor acute lymphoblastic leukemia (BCP-ALL), acute myeloid leukemia (AML), and T cell acute lymphoblastic leukemia (T-ALL). By using immunofluorescence microscopy and flow cytometry we observed that CD22 is expressed not only in the cytoplasm (as previously reported) but also on the cell surface of virtually all (15/16) BCP-ALL examined. CD22 that was biosynthetically labeled with 35S-cysteine and immunoprecipitated from the uncommon cytoplasmic CD22- positive/surface CD22-negative BCP-ALL cells was analyzed by single- dimension sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Our results indicated that the cytoplasmic form of CD22 comigrated with 125I/lactoperoxidase-labeled surface CD22. Therefore, cytoplasmic CD22 is probably a pool of fully processed glycoprotein. We also observed unusual cases of AML (approximately 20%) that expressed cytoplasmic CD22 based on immunofluorescent staining; however, biosynthetic labeling and immunoprecipitation revealed an apparently cross-reactive protein(s) of approximately 250 to 300 kd in AML cells. No T-ALL cell lines examined expressed either cytoplasmic or surface CD22. Thus, cytoplasmic and surface expression of bona fide CD22 appears restricted to B cells, which suggests that this molecule subserves a function unique to B cells.  相似文献   
94.
Minactivin expression in human monocyte and macrophage populations   总被引:4,自引:0,他引:4  
Adherent monolayer cultures of human blood monocytes, peritoneal macrophages, bone marrow macrophages, and colonic mucosa macrophages were examined for their ability to produce and secrete minactivin, a specific inactivator of urokinase-type plasminogen activator. All except colonic mucosa macrophages produced and secreted appreciable amounts of minactivin, but only blood monocytes were stimulated by muramyl dipeptide (adjuvant peptide) to increase production. The minactivin from each of these populations could be shown to preferentially inhibit urokinase-type plasminogen activator and not trypsin, plasmin, or "tissue"-type plasminogen activator (HPA66). A plasminogen-activating enzyme present in monocyte cultures appeared unaffected by the presence of minactivin and could be shown to be regulated independently by dexamethasone.  相似文献   
95.
Interaction of platelet plasma membranes with thrombin-activated platelets   总被引:1,自引:0,他引:1  
Prasanna  HR; Edwards  HH; Phillips  DR 《Blood》1981,57(2):305-312
This study described the binding of platelet plasma membranes to either control or thrombin-activated platelets. Glycoproteins in plasma membranes isolated from human platelets were labeled by oxidation with periodate followed by reduction with [3H]NaBH4. Labeled membranes were incubated with either control or thrombin-activated platelets. The amount of membranes bound was measured by separating platelets with bound membranes from solution by rapid centrifugation through 27% sucrose and determining the amount of radioactivity associated with platelets. Five- to sevenfold more membranes bound to thrombin- activated platelets than to control platelets. This enhanced binding of labeled membranes was completely inhibited by an excess of unlabeled platelet membranes. Human erythrocyte membranes had little affinity for either washed or thrombin-activated platelets and therefore did not compete for platelet-membrane binding. Binding of platelet membranes to thrombin-treated platelets was inhibited by prior incubation of the platelets with PGI2 suggesting that the enhanced binding of membranes was to activated platelets. This study demonstrates that the purified platelet membranes have functional sites that can mediate membrane binding to platelets and that quantitation of membrane binding appears to reflect the increased aggregation capability of activated platelets.  相似文献   
96.
Clark  LJ; Chan  LS; Powars  DR; Baker  RF 《Blood》1981,57(4):675-678
Negative charges on the external surface of red cells were visualized by colloidal iron hydroxide labelling of 50% of the membrane area after osmotic hemolysis and glutaraldehyde fixation. Counts were made over randomly selected areas on electron micrographs at 350,000 x magnification. Statistical analyses showed that at the 95% level of confidence there was no significant difference between oxygenated normal (AA) and sickle (SS) cells in either the distribution or the density of negative charges.  相似文献   
97.
OBJECTIVE: Clinical studies examining stress-related gastrointestinal bleeding in critically ill patients vary in their clinical definitions and assessment of clinical significance. Although there is evidence that routine prophylaxis decreases stress-related gastrointestinal bleeding, recent studies indicate a decreasing incidence, independent of the use of prophylactic medications. The purpose of this study was to determine the incidence of and risk factors for clinically significant, endoscopically proven gastrointestinal bleeding in critically ill patients. METHODS: A database (prospectively collected data) of 8338 patients admitted to the surgical and medical intensive care units at major tertiary care center from July 1988 to April 1995 was examined. All patients with significant upper gastrointestinal bleeding as defined by a drop in hemoglobin of >20 g/L and endoscopic evidence of an upper GI tract source were identified. Risk factors for GI bleeding from stress ulceration were compared in bleeding and nonbleeding patients. A case-control study analyzing risk factors for bleeding in the abdominal aortic aneurysm subgroup was performed. RESULTS: After exclusion criteria, 12/7231 (0.17%) patients had clinically significant, endoscopically proven bleeding. Significant risk factors included age, septic shock, abdominal aortic aneurysm repair, and nutritional support. Intensive care unit stay was prolonged in patients with stress-related bleeding. There was no difference in incidence of hypotension, clamp time, APACHE score, or operating room time in patients with abdominal aortic aneurysm repair as compared with controls. CONCLUSIONS: In an intensive care unit where stress prophylaxis is widely used, clinically important gastrointestinal bleeding is uncommon. Further study is needed to define the optimal prophylaxis regimen and the role for its selective use in high-risk patients.  相似文献   
98.
Wolf  DL; Lin  PH; Hollenbach  S; Wong  A; Phillips  DR; Sinha  U 《Blood》1995,86(11):4153-4157
The plasma clotting factors used to treat hemophiliacs who have developed inhibitory antibodies have a shared history of limited clinical safety and utility. To improve on existing bypass factors, we have developed a reversibly acylated form of human plasma factor Xa capable of providing a time-dependent release of procoagulant activity. Factor Xa was treated with p-amidinophenyl p'-anisate to generate anisoyl Xa. The chemical modification of the protein involves acylation of the active site serine residue of factor Xa. Anisoyl Xa deacylated in a time, pH, and temperature-dependent manner. Active factor Xa generated on deacylation of anisoyl Xa exhibited amidolytic and prothrombinase complex activities in in vitro assays, the level being comparable to those of untreated factor Xa. When Anisoyl Xa was infused into rabbits, active factor Xa was generated on deacylation of the acylated enzyme, which shortened the activated partial thromboplastin time (APTT) in a dose-dependent manner. The duration of effect on rabbit APTT could be directly correlated to the level of human plasma factor Xa. Because anisoyl Xa bypasses the "tenase" complex that is compromised in hemophilia A and B and is unaffected by inhibitory antibodies, it has the potential to be used as an effective bypass therapy.  相似文献   
99.
In an attempt to decrease the relapse rate after bone marrow transplantation (BMT) for advanced acute leukemia, we initiated studies using 131I-labeled anti-CD45 antibody (BC8) to deliver radiation specifically to hematopoietic tissues, followed by a standard transplant preparative regimen. Biodistribution studies were performed in 23 patients using 0.5 mg/kg trace 131I-labeled BC8 antibody. The BC8 antibody was cleared rapidly from plasma with an initial disappearance half-time of 1.5 +/- 0.2 hours, presumably reflecting rapid antigen- specific binding. The mean radiation absorbed doses (cGy/mCi131I administered) were as follows: marrow, 7.1 +/- 0.8; spleen, 10.8 +/- 1.4; liver, 2.7 +/- 0.2; lungs, 2.1 +/- 0.1; kidneys, 0.7 +/- 0.1; and total body, 0.4 +/- 0.03. Patients with acute myelogenous leukemia (AML) in relapse had a higher marrow dose (11.4 cGy/mCi) than those in remission (5.2 cGy/mCi; P = .001) because of higher uptake and longer retention of radionuclide in marrow. Twenty patients were treated with a dose of 131I estimated to deliver 3.5 Gy (level 1) to 7 Gy (level 3) to liver, with marrow doses of 4 to 30 Gy and spleen doses of 7 to 60 Gy, followed by 120 mg/kg cyclophosphamide (CY) and 12 Gy total body irradiation (TBI). Nine of 13 patients with AML or refractory anemia with excess blasts (RAEB) and two of seven with acute lymphocytic leukemia (ALL) are alive disease-free at 8 to 41 months (median, 17 months) after BMT. Toxicity has not been measurably greater than that of CY/TBI alone, and the maximum tolerated dose has not been reached. This study demonstrates that with the use of 131I-BC8 substantially greater doses of radiation can be delivered to hematopoietic tissues as compared with liver, lung, or kidney, which may improve the efficacy of marrow transplantation.  相似文献   
100.
Sharpe  JA; Summerhill  RJ; Vyas  P; Gourdon  G; Higgs  DR; Wood  WG 《Blood》1993,82(5):1666-1671
Erythroid-specific DNase 1 hypersensitive sites have been identified at the promoters of the human alpha-like genes and within the region from 4 to 40 kb upstream of the gene cluster. One of these sites, HS-40, has been shown previously to be the major regulator of tissue-specific alpha-globin gene expression. We have now examined the function of other hypersensitive sites by studying the expression in mouse erythroleukemia (MEL) cells of various fragments containing these sites attached to HS-40 and an alpha-globin gene. High level expression of the alpha gene was observed in all cases. When clones of MEL cells bearing a single copy of the alpha-globin gene fragments were examined, expression levels were similar to those of the endogenous mouse alpha genes and similar to MEL cells bearing beta gene constructs under the control of the beta-globin locus control region. However, there was no evidence that the additional hypersensitive sites increased the level of expression or conferred copy number dependence on the expression of a linked alpha gene in MEL cells.  相似文献   
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