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671.
Activation of platelets may be measured by using the monoclonal antibody S12 to detect alpha granule membrane protein 140 (GMP-140) antigen expressed only on activated platelets. S12 was used to measure activation of apheresis platelet concentrates by flow cytometry. Eleven platelet concentrates obtained by one method and nine obtained by another were analyzed 4 hours after collection. Means +/- 1SD of 25.3 +/- 14.8 percent and 28.9 +/- 11.6 percent, respectively, of platelets were found to be activated (range, 4.8-53.1%). Six of the platelet concentrates obtained by the second method were filtered. There was a drop of 17.8 percent (range, 10-25%) in the mean total number of platelets recovered after filtration, but there was no difference in the proportion of activated platelets measured immediately before and after filtration. The 1-hour posttransfusion platelet count increment was obtained after 12 of these apheresis platelet concentrates were transfused to eight patients who were not refractory from either a clinical or alloimmune standpoint. There was a significant inverse correlation between the platelet count increment and the proportion of activated platelets in the component (p less than 0.05, r = -.58). These data suggest that apheresis platelet concentrates with more activated platelets have a reduced 1-hour recovery. Filtration did not enhance activation or selectively remove activated platelets. Expression of GMP-140 may serve as a useful quality control measurement.  相似文献   
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Factors affecting a patient's ability to carry out partial weight bearing after operation for hip fracture were studied in 100 patients. Seventy-six were able to do so. Significant factors included the muscle power of the good limbs and the mental state, whereas age, body-weight and type of operation were not significant. Logistical regression analysis showed that it was possible to predict a patient's partial weight bearing potential by simply testing the left hand grip and the 'Set' test score.  相似文献   
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Using the benzoylated naphthoylated DEAE cellulose method (BND-method) we have designed a more efficient approach for the detection of human papillomavirus-DNA (HPV-DNA) via dot-blot and hybridization. Biopsy material from anogenital warts (40 patients), invasive carcinoma uteri (12 patients) and normal controls (20 patients) were studied for the presence of HPV-DNA. Phenol extracted DNA from representative lesions was loaded onto a pretreated nitrocellulose filter, was incubated under stringent conditions with 32-P-dCTP labelled HPV-DNA and exposed to a Kodak X-OMAT film. DNA of HPV types 11, 16, 18 were cloned into plasmid vectors. The common, time-consuming caesium-chloride density-gradient centrifugation used for purification of plasmid DNA (20-36 h), was substituted by the BND-method (15 min). Complete HPV genomes were excised using the restriction endonucleases Eco RI and Bam HI. The HPV-DNA fragments obtained were then electroeluted using the 'Bio-Trap' method and subsequently labelled with 32P-dCTP by nick translation. Without resorting to more complex and sensitive technology, such as the polymerase chain reaction, efficiency of specific analysis of large numbers of cervical samples and condylomata was achieved without loss of accuracy or increased costs. The time required for HPV identification from biopsy or sample receipt was shortened considerably (approximately 50%).  相似文献   
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