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11.
We report microchromatographic measurement of fetal hemoglobin (HbF) proportions in a 36-year-old African-American multigravida woman. At 34 weeks she delivered a 630-g male infant who subsequently did well. Hemoglobin electrophoresis of the hemolysate revealed nearly 100% HbF without HbA, an extremely unusual naturally occurring sample. Family studies revealed a combination of hereditary persistence of fetal hemoglobin (HPFH) and beta zero-thalassemia minor. Southern blot technique confirmed heterozygous alpha 2 thalassemia and HPFH but failed to identify the beta thalassemic lesion. The absence of HbA and the very high amounts of HbF led us to measure HbF by several methods to confirm the accuracy of microchromatography of HbF at values approaching 100%. HPLC revealed a 14% F1 suggestive of microchromatographic underestimation due to glycated HbF. We conclude that cation-exchange microchromatography and the Betke method of alkali denaturation underestimate HbF values as they approach 100% and do not recommend these procedures in this rare situation. 相似文献
12.
13.
Maternal hypercoagulability in normal pregnancy results from significant increases in blood factors that promote thrombosis or decreases in factors that inhibit thrombosis, such as antithrombin III (AT-III) and proteins C and S. The precise role of these factors in puerperal hemostasis is not clear. In 10 normal, pregnant women at term undergoing scheduled repeat cesarean section, the percent activities of AT-III, proteins C and S, and C4b-binding protein were determined in peripheral venous blood preoperatively and in samples of uterine venous blood before the uterine incision was made and 5 and 15 minutes after placental delivery using the Laurell Rocket electroimmunodiffusion technique. The mean percent activities of AT-III (73%), protein S (81%) and C4b-binding protein (85%) were lower than those in nonpregnant controls, were similar in peripheral and uterine venous blood and were unchanged after placental delivery. These data suggest that such factors may not play an important role in acute uteroplacental hemostasis during normal pregnancy. 相似文献
14.
Hans-Holger Capelle Johannes C W?hrle Ralf Weigel Hansj?rg B?zner Eva Grips Joachim K Krauss 《Movement disorders》2004,19(10):1202-1208
It is well known that brain injury or central traumatic lesions may result in the subsequent appearance of movement disorders such as dystonia or tremor. The concept that peripheral lesions to neural structures may be involved in the pathogenesis of movement disorders has been discussed controversely but has gained more widespread acceptance only recently. Here, we report on 6 patients who developed movement disorders after spinal disc surgery. The movement disorders became manifest with a delay of 1 day to 12 months after surgery. Of the six patients, 4 underwent cervical disc surgery, and 2 patients were operated on for lumbar disc herniation; 2 patients presented with paroxysmal kinesigenic segmental dystonia, 1 patient with focal dystonia, 2 with unilateral tremor, and 1 with bilateral tremor. The appearance of the movement disorder was associated with persistent dermatomal or segmental pain. In all patients, the anatomic distribution of the movement disorder was related to the nerve root or spinal segment of the corresponding disc level and the manifestation was in close temporal relation to the surgery. We conclude that spinal disc surgery may be another, thus far neglected, cause for movement disorders. The postoperative pain syndrome in all patients should be considered as an important factor of pathogenesis. Overall, movement disorders associated with disc surgery appear to be rare, yet they may cause significant discomfort to the affected individual. 相似文献
16.
Two cases, carefully selected from a longitudinal, prospective investigation of the relationship between psychosocial variables and postsurgical adjustment to a penile prosthesis implantation, were studied intensively. In both cases, the patient and sexual partner were assessed, presurgically, on a number of psychological, marital, and sexual functioning variables; their subsequent satisfaction with the prosthesis, and their psychological, marital, and sexual adjustment were measured at 6 and 12 months postsurgery. Despite many similarities in medical aspects of the surgery, for one couple a successful outcome was evidenced, whereas the other couple demonstrated a therapeutic failure despite the technical success of the surgery. Psychosocial differences between the couples were identified as they may relate to the discordant outcomes observed. Clinical implications of these results are discussed, as are the strengths and weaknesses of our methodological approach. 相似文献
17.
Reassortment and interspecies transmission of North American H6N2 influenza viruses 总被引:21,自引:0,他引:21
To identify the protein encoded by a 687-bp open reading frame (ORF) of a salI genomic DNA fragment of shrimp white spot syndrome virus (WSSV), we expressed the ORF in a baculovirus/insect cell expression system. The apparent molecular mass of the recombinant protein on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was 35 kDa in insect cells. Antibody raised against bacterially synthesized protein of the ORF identified a nucleocapsid protein (VP35) in the extracts of both the purified WSSV virions and the nucleocapsids which comigrated with the 35-kDa baculovirus-expressed recombinant protein on SDS-PAGE. We also show by transient expression in insect cells (Sf9) that VP35 targets the nucleus. Two potential nuclear localization signals (NLSs) were characterized, but only one of them was important for targeting VP35 to the nuclei of transfected insect cells. Replacement of a cluster of four positively charged residues ((24)KRKR(27)) at the N terminus of the protein with AAAA resulted in mutant proteins that were distributed only in the cytoplasm, thus confirming that this sequence is a critical part of the functionally active NLS of VP35. 相似文献
18.
A current topic in neurobiology is the study of the role of various brain structures in processing of spatial information. The present study was aimed at elucidating the role of the rat posterior parietal cortex in performing a place avoidance task. Two variants of the task were used: an arena frame task, in which animals were trained to avoid a sector defined by local cues bound to the surface of a rotating arena, and the room frame task, in which the shock sector was defined with respect to distal room landmarks. The results showed that both control and lesioned rats were able to efficiently solve both tasks, while locomotion was not altered. These results suggest that the posterior parietal cortex is not crucial for the processing of either proximal or distal cues in place avoidance. 相似文献
19.
J S Krauss D A Hahn D Harper S Shell C R Baisden 《Annals of clinical and laboratory science》1987,17(5):331-338
The glycated hemoglobin (GHb) is lowered by hemolytic anemia. The cation-exchange HbA1 has been shown to be lowered by hereditary spherocytosis (HS). The HbA1, however, can be increased by elevations of fetal hemoglobin (HbF). The affinity GHb, a parameter related to, but not identical with, the HbA1, and unaffected by HbF, has been shown to be low in hemoglobinopathies but not, to our knowledge, in HS and other non-hemoglobinopathic hemolytic anemias. Therefore, the affinity GHb and HbF was determined in four members of an HS family and in nine other cases of non-hemoglobinopathic hemolytic anemia, including three autoimmune hemolytic anemias, four red cell fragmentation syndromes (two "Waring blender" syndromes, one thrombotic thrombocytopenic purpura in association with tumor, and one case of disseminated intravascular coagulation), and two red cell membrane defects: paroxysmal nocturnal hemoglobinuria and another case of hereditary spherocytosis. The GHb for these nine cases was 3.6 +/- 1.7 percent (normal 6.0 +/- 2.0 percent; p less than 0.001). The reticulocyte count, available in four cases, was 0.23 +/- 0.14 and correlated negatively with the GHb. The average GHb in the HS family was 3.9 +/- 0.8 percent, which was significantly less than the normal of 6.0 +/- 2.0 percent (p less than 0.001); the HbF was less than 1.0 percent. It is concluded that the GHb is diminished in hemolytic anemias not associated with hemoglobinopathies and that this lowering reflects the shortened red cell life span in these processes. To our knowledge, this is the first report of low GHb in hemolytic anemia not associated with hemoglobinopathy, by the affinity chromatographic technique, as opposed to the cation-exchange chromatographic technique. 相似文献
20.
Various salient histological features were rated from + to +++ in a semiquantitative evaluation of a series of 155 cases of fibrous histiocytoma. Relations between individual histological features, as well as between histological findings, localisation and size of lesions, and age or sex of the patient were tested statistically. Most impressive was an inverse proportional relationship between cellular and fibrillar densities: highly cellular fibrous histiocytomas chiefly showed little fiber formation. Accordingly, cases with marked fiber formation were distinguished by low cellularity. Based on this statistically significant relation, 3 subtypes could be classified on a scale of increasing fiber formation and decreasing cellular density. The majority of cases showed medium cellularity and fibrillar density, with distinct storiform (spokewheel or "whirlygig") pattern which is compatible with typical storiform histocytoma, including clincally progressive, recurrant FH and/or "dermatofibrosarcoma protuberans". The typical patient was more frequently female than male, 40 years of age with a 0.5 to 1.0 cm size tumor node in the lower extremities located in the corium, often with beginning infiltration of the subcutaneous fat tissue. 相似文献