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The acrosome reaction is an important marker for human sperm function. Since different laboratory techniques may be used for the detection of this exocytotic process, the purpose of the present study was to compare three common markers [Pisum sativum agglutinin (PSA), concanavalin A (ConA), double staining] and transmission electron microscopy for identification of acrosomal changes. Preliminary findings had demonstrated that similar results were achieved with Trypan Blue and Hoechst 33258 staining. Therefore, supravital stainings were omitted. In various experiments, human spermatozoa were treated with two concentrations (10 and 3.3 microM) of calcium ionophore A23187 for 15, 30 and 60 min after capacitation for 3 and 6 h at 37 degrees C. The percentages of spermatozoa with acrosomal loss detected by fluorescein isothiocyanate (FITC)-ConA were consistently lower than those obtained by double staining or FITC-PSA, which showed comparable results. Following 6 h of capacitation and incubation with 10 microM ionophore for 1 h at 37 degrees C, 25.9 +/- 15.7% of all spermatozoa showed almost complete loss of the acrosomal content. Binding of FITC- ConA to the acrosomal region was observed in 27.0 +/- 13.2% of spermatozoa obtained from the same sample. FITC-ConA and double staining or FITC-PSA detect different stages of the acrosome reaction and may be helpful for a differentiated evaluation of this sperm function.   相似文献   
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The reliability and clinical applications of computerised image analysis measurement of bowel uptake of Tc-99m HMPAO labelled leucocytes has been examined as a measure of disease activity in Crohn's disease. In 54 studies carried out on 33 patients with established Crohn's disease, the mean 'scan score', a quantitative assessment of image intensity, was 82.1 SEM (13.6), in patients with clinically active disease compared to 24.7 (7.0) in those with quiescent disease, p < or = 0.0005. A significant correlation was found between the scan score and Crohn's Disease Activity Index (rs = 0.52, p < 0.0001), and Harvey and Bradshaw Simple Index (rs = 0.4, p < 0.004). A low scan score correctly identified seven patients whose raised Crohn's Disease Activity Index incorrectly indicated active disease because symptoms used in calculation of the index were not caused by active inflammation. Of the laboratory measurements, the scan score correlated with the haemoglobin (rs = 0.66, p < 0.0001), albumin level (rs = -0.6, p < 0.0001), C-reactive protein (rs = 0.7, p < 0.0001), alpha-acid glycoprotein (rs = 0.57, p < 0.001), and platelet count (rs = 0.47, p < or = 0.006), but not with the erythrocyte sedimentation rate (rs = 0.2, p < or = 0.25). The scan score was raised in all patients who had clinically active disease but normal laboratory tests. The results of this study indicate that the scan score provides an objective indicator of disease activity in Crohn's disease which may be superior to clinical indices, and also to laboratory tests which although objective are often normal in the presence of active disease.  相似文献   
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Practicing thoracic surgeons were randomly surveyed to evaluate how computed tomography (CT) has influenced the preoperative evaluation of bronchogenic carcinoma. Thirty-six percent of the 529 respondents routinely requested CT and 62% did so selectively. Approximately 40% indicated that CT provided useful information in most cases. Nearly all surgeons (98.7%) do not rely on the identification of enlarged lymph nodes with CT to spare the patient surgical staging; however, 77.5% are influenced by CT results in their staging procedures. Fifty-seven percent reported that a negative CT study eliminates surgical staging entirely unless the patient has a "coin lesion," in which case 75% are willing to proceed directly to thoracotomy. For surgeons who use CT selectively, an abnormal mediastinal contour on the radiograph was the most frequent radiologic abnormality to prompt CT (85%). Thirty-seven percent are influenced by tumor histology in their decision to request CT. There was little difference in the pattern of CT use between university and community hospital surgeons.  相似文献   
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Cricketers suffer from higher rates of depression than both the general public and other sportsmen, as evidenced by the high suicide rates amongst retired test cricketers compared with age-matched controls. This is likely due to a complex array of psychosocial factors including the nature of sportsmen that play cricket, the unique nature of the sport, the duration of matches and hence the time away from support networks and the social situation of cricketers in the pre-professional era.  相似文献   
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BACKGROUND: The purposes of this study were to determine the overall incidence of platelet refractoriness and alloimmunization among multiply transfused children on a medical oncology and bone marrow transplant service and to evaluate the effect of routine white cell reduction in blood components on that incidence. STUDY DESIGN AND METHODS : The platelet transfusion records of 128 consecutive children admitted to the hospital and requiring blood component support for the treatment of disease were evaluated retrospectively. Mean corrected count increments (CCIs) for each patient were calculated for all random- donor platelet transfusions given within 7 days of the routine weekly testings of the patient's serum for lymphocytotoxic antibodies (LCTAbs). Mean CCIs for HLA-matched platelet transfusions were calculated separately for the patients receiving them. RESULTS : Thirty- one patients (24%) had or developed persistently positive LCTAbs (patient's serum reacted with > or = 3/10 panel lymphocytes); 22 (71%) of these patients had a mean CCI < 7.5 to random-donor platelet transfusions. In contrast, of the 97 patients with negative or transiently positive LCTAbs, only 25 (26%) had a mean CCI < 7.5. The overall incidence of platelet refractoriness (CCI < 7.5) was 37 percent. Patients with acute myelogenous leukemia had a significantly (p < 0.01) reduced incidence (17%) of low CCIs, with or without positive LCTAbs, as compared to patients with other malignant or nonmalignant disorders (41%). No difference in the incidence of LCTAbs or low CCIs was seen in patients undergoing allogeneic or autologous bone marrow transplant or receiving drug therapy only. Among the 24 patients who received HLA-matched platelets, only those with positive LCTAbs showed a significant improvement in CCIs over that achieved with random-donor platelet transfusions. Routine white cell reduction in red cell and platelet components with third-generation white cell filters was performed prior to transfusion in 73 of the patients. There was no significant difference between the incidence of LCTAbs and/or low CCIs in this group and that in the 55 children receiving unfiltered transfusions. CONCLUSION : Alloimmunization and platelet refractoriness occur in pediatric oncology and bone marrow transplant patients, but the incidence-particularly in children with acute myelogenous leukemia- -appears to be low. The detection of LCTAbs predicts a poor response to random-donor platelet transfusion, but most such patients show improved CCIs with HLA-matched platelets. Routine use of white cell-reduction filters has thus far failed to eliminate alloimmunization in children requiring prolonged blood component support.  相似文献   
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Human herpesvirus 6 activity (HHV-6) was studied in 15 allogeneic and 11 autologous marrow transplantation patients. After transplantation, HHV-6 was isolated from the peripheral blood mononuclear cells of 12 of 26 patients (6 allogeneic and 6 autologous). All isolates were variant B. Eleven of 26 and 12 of 19 patients showed salivary shedding of HHV-6 DNA before and after transplantation, respectively. The antibody titer increased in 7 of 26 patients. Thus, 23 of 26 patients showed evidence of active HHV-6 infection either by virus isolation, salivary shedding, or increases in antibody titers. The fraction of saliva specimens positive in 19 patients was negatively associated with their antibody titers (P= .005). The proportion of cultures positive increased after transplantation (P = .007). Sinusitis was associated with HHV-6 isolation in autologous recipients (P= .002). In allogeneic patients, active human cytomegalovirus infection was associated with HHV-6 isolation (P = .04). No association was observed between HHV-6 infection and GVHD, pneumonia, delay in engraftment, or marrow suppression. Of the 120 clinical events analyzed in 26 patients, HHV-6 was defined as a probable cause of 16 events in 9 patients based on the propinquity of HHV-6 activity and the clinical event plus the absence of other identified causes of the event.  相似文献   
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