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81.
Duodenoscopy was undertaken in 143 patients with upper gastrointestinal tract symptoms. There were no complications of the procedure. The duodenum was successfully entered in 98% of attempts, and in 90% of patients the examination was judged to be technically successful. When compared with radiological assessment, the findings at duodenoscopy significantly altered diagnosis and management in 21% of patients. The endoscopic appearance of the non-ulcerated duodenal mucosa could not be consistently correlated with changes found in biopsy tissue obtained under direct vision. Duodenoscopy is a valuable adjunct in the clinical assessment of upper gastrointestinal tract symptoms suspected to be due to pathological changes in the duodenum. 相似文献
82.
Analysis of cytotoxic effector cell function in patients with leukemia or aplastic anemia before and after marrow transplantation 总被引:2,自引:0,他引:2
S Livnat M Seigneuret R Storb R L Prentice 《Journal of immunology (Baltimore, Md. : 1950)》1980,124(1):481-490
Cytotoxic effector cells mediating natural killing (NK), antibody-dependent cellular cytotoxicity (ADCC), and lectin-dependent cellular cytotoxicity (LDCC) were studied in patients with leukemia or aplastic anemia before and/or after marrow transplantation. Before transplantation, about one-third to one-half of the patients were deficient in cytotoxic activity. In patients with leukemia, this was most likely due to large numbers of circulating blast cells diluting or replacing the effector cells. In patients with aplastic anemia there was an apparent absence of the effector cells in a proportion of the patients. After marrow transplantation, cytotoxic activity in all three systems returned to normal rapidly, by 30 days, and remained so through 100 days. However, about 20% of patients studied beyond 1 year were deficient in these functions. There were no significant associations between cytotoxic activity and important clinical parameters including infections, graft-vs-host disease, and recurrence of leukemia. Our findings do not support an immunosurveillance role for NK against leukemia after marrow transplantation. Furthermore, they point out the need for new in vitro approaches for meaningful monitoring of marrow transplant patients. Finally, our results showed a significant discordance between NK, ADCC, and LDCC activities in these immunologically perturbed individuals, indicating that either different cell populations or different cellular mechanisms are involved in these cytotoxic functions. 相似文献
83.
G D Lowe M M Drummond A R Lorimer I Hutton C D Forbes C R Prentice J C Barbenel 《BMJ (Clinical research ed.)》1980,280(6215):673-674
Blood viscosity (shear rate 100/s) and its major determinants (packed cell volume, plasma fibrinogen concentration, and plasma viscosity) were measured before coronary angiography in 50 men aged 30-55 and related to the extent of coronary artery disease. Twenty-six men had extensive disease (stenosis of two or three major coronary vessels), and 24 had either stenosis of one vessel or no stenosis. The 26 men with extensive disease had significantly higher mean blood viscosity than those with mild or no disease and 25 healthy controls (p less than 0.001). The increased viscosity was due partly to a higher packed cell volume and partly to a higher fibrinogen concentration; plasma viscosity was not significantly increased. These differences could not be explained by smoking history. These results suggest an association between increased blood viscosity and extensive coronary artery disease in men, which merits further investigation. 相似文献
84.
Activities of barley peptide hydrolases A (acidic peptidase) and H (neutral peptidase) were examined in the growing embryo and in the embryoless tissues of Himalaya barley incubated for 70 hours. Tissues examined were roots, shoots, embryo residue (scutellum + seutellar node + coleorhiza) and the embryoless portion of the kernel. Activity of the hydrolase A increased mainly in the embryo residue during 0 to 30 hours but little thereafter. Activity of hydrolase B increased mainly in the embryo residue but did so linearly over the 70 hour period. A small linear increase occurrence in the embryoless portion during this lime. 相似文献
85.
R. M. Lindsay C. R. M. Prentice J. F. Davidson J. A. Burton G. P. McNicol 《BMJ (Clinical research ed.)》1972,4(5838):454-458
Platelet counts, coagulation factors, and the fibrinolytic system were studied in seven regular dialysis patients during the course of haemodialysis by parallel flow (Gambro-Alwall) and coil (Travenol Ultra-Flo 100) dialysers. Significant falls in the patients'' platelet counts and rises in their factor V levels were found with both dialysis systems. The changes were more pronounced over the course of a Gambro-Alwall dialysis, when significant falls in the partial thromboplastin clotting time and in the plasminogen levels were also noted. These haemostatic changes were associated with the retention of platelets on the dialysis membranes and, in the case of the Gambro-Alwall dialyser, with the formation of platelet-fibrin thrombus. This thrombus formation may take place in spite of efficient heparin anticoagulation and may cause excessive blood loss to the regular dialysis patient. 相似文献
86.
The Use of Density Gradient Centrifugation for the Separation of Germinated from Nongerminated Spores 总被引:1,自引:1,他引:0
S ummary : The density gradient centrifugation of a suspension of spores of B. subtilis 8057 on both sucrose and renografin gradients gave 2 distinct fractions. Germination evidence suggested that the heavier fraction consisted of dormant spores and the less dense fraction, germinated spores. It is concluded that density gradient centrifugation may provide a useful technique for the separation of germinated from nongerminated spores. 相似文献
87.
88.
New tests for trend in proportions, in the presence of historical control data, are proposed. One such test is a simple score statistic based on a binomial likelihood for the "current" study and beta-binomial likelihoods for each historical control series. A closely related trend statistic based on estimating equations is also proposed. Trend statistics that allow overdispersed proportions in the current study are also developed, including a version of Tarone's (1982, Biometrics 38, 215-220) test that acknowledges sampling variation in the beta distribution parameters, and a trend statistic based on estimating equations. Each such trend test is evaluated with respect to size and power under both binomial and beta-binomial sampling conditions for the current study, and illustrations are provided. 相似文献
89.
A medium for the detection of Lancefield Group D cocci in skimmed milk powder by measurement of conductivity changes 总被引:1,自引:0,他引:1
A selective medium for the detection of Lancefield Group D cocci in skimmed milk powder by conductivity measurements was developed and evaluated using the Bactometer M123 and Malthus 128H systems. This medium promoted large changes in conductance and capacitance. The calibration curve of detection times vs concentration of Lancefield Group D cocci showed a linear correlation coefficient of 0.93 and the method gave comparable results in both conductivity instruments. Naturally contaminated samples containing c. 10(3) cfu/g of Lancefield Group D cocci gave detection times within 16-18 h which was sufficiently rapid for the medium to be used for the routine screening of skimmed milk powder. 相似文献
90.