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排序方式: 共有173条查询结果,搜索用时 15 毫秒
81.
Neutrophil surface markers in patients with acute leukemia   总被引:1,自引:0,他引:1  
Hofmeister  BG; Carrera  CJ; Barrett  SG 《Blood》1981,57(2):372-376
The presence of complement and Fc receptors on neutrophils from patients with acute leukemia was investigated at different stages of the leukemic process. Both Fc receptors (Fc-H and Fc-R) and one complement receptor (C3d) were normal when patients were studied at diagnosis, in relapse, and in remission. In contrast, the C3b receptor was significantly reduced on te neutrophils at the time of diagnosis, but returned to normal levels when patients entered remission. Variable amounts of C3b activity were observed in patients relapse, with approximately one-half of the patients showing decreased C3b activity. To determine whether the reduction inC3b receptors was specific for patients at diagnosis, three patients were studied at different times during their diseases. Normal receptor levels were detected in these patients during remission, but the C3b receptor was markedly reduced at diagnosis and at relapse.  相似文献   
82.
We have previously shown that the number of glucocorticoid receptors (GR) per cell in malignant lymphoblasts from children with newly diagnosed pre-B- and early pre-B-cell acute lymphoblastic leukemia (ALL) has a positive correlation with the probability of successful remission induction (Quddus et al, Cancer Res, 45:6482, 1985). We report now on the long-term outcome for these patients treated on a single protocol with 3 different treatment arms, all of which included glucocorticoid pulses during maintenance therapy. GR were quantitated in leukemic cells from 546 children with ALL at the time of diagnosis. Immunophenotyping studies were performed on all specimens. Prior studies showed that in pre-B- and early pre-B-cell ALL, successful remission induction was associated with a median GR number of 9,900 sites/cell, whereas induction failure was associated with a median receptor number of 4,800 sites/cell. Long-term follow-up of these patients shows an association between higher GR number and improved prognosis. The 5-year event-free survival of 61.0% (SE 2.8%) for patients whose leukemic cells had greater than 8,000 receptors/cell and 47.3% (SE 3.3%) for those with less than 8,000 receptors/cell is significantly different (P < .001). This difference remains significant when adjusted multivariately for blast immunophenotype and clinical risk factors (P < .001) or for treatment type (P < .001). We conclude that GR number greater than 8,000 sites/leukemic cell is a favorable prognostic marker for children with acute lymphocytic leukemia. This finding offers deeper insights into molecular mechanisms of anti- leukemia therapy and suggests that manipulation of steroid receptor number might augment the antitumor response, thus opening new avenues for basic and clinical research.  相似文献   
83.
Spectrin Tunis (Sp alpha I/78) is an alpha l domain variant that causes asymptomatic elliptocytosis in the heterozygote state. It is manifested by a reduction of spectrin dimer self-association and by the development of a major 78-Kd fragment at the expense of the alpha l 80- Kd fragment upon spectrin-limited digestion. Amino acid sequence analysis, following peptide transfer onto Immobilon membranes, showed that the 78-Kd fragment results from a sensitized cleavage after lysyl residue 10. Using a 13.5-kb genomic alpha-spectrin probe and the Xbal, Pvull, and Mspl polymorphic sites detected with this probe, we concluded that spectrin Tunis is associated with the + - + haplotype (in the above order). Twenty mer oligonucleotides, complementary to genomic segments from introns 2 and 3, respectively, were synthesized. We then performed DNA amplification and sequencing. In the two investigated carriers of spectrin Tunis, we found the C----T base substitution of the codon corresponding to position 35 of the alpha l domain (CGG----TGG; Arg----Trp). The mutation lies in the last part of an alpha helix that extends from residues 9 to 44 of partial repeat alpha 1' and is comparable with helix 3 of full repeats 1 to 5. The modified proteolytic site, located 25 amino acid residues upstream, occurs at the beginning of the helix.  相似文献   
84.
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86.
Leiomyomas in pregnancy: sonographic study   总被引:16,自引:0,他引:16  
With ultrasound monitoring, analysis of the behavior of uterine leiomyomas (fibroids) and their impact on the course of pregnancy was undertaken in a group of 113 patients. Fibroid size changes were analyzed on the basis of trimesters. In the second trimester, smaller fibroids increased in size, whereas larger fibroids decreased in size. In the third trimester, a decrease in size was documented regardless of initial size. The most common patterns of echotexture were hypoechoic, heterogeneous, and echogenic rim. The development of a heterogeneous pattern or anechoic/cystic spaces on a follow-up study was accompanied in seven of ten patients by severe abdominal pain, compared with 12 cases of abdominal pain in 103 patients without such echotexture changes. Although the number of patients was small, the development of these patterns apparently indicates significant degeneration of the fibroid. Fibroids located in the lower uterine segment were accompanied by a higher frequency of cesarean section and retained placenta. Fibroids located in the uterine corpus were more frequently associated with early abortions. Multiple fibroids were accompanied by a higher frequency of malpresentation and premature contractions compared with cases with one or two fibroids.  相似文献   
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88.
Purpose:?To develop a questionnaire based on the theory of planned behaviour (TPB) to predict prosthetic use.

Method:?In part one, 31 amputees over 50 years of age with peripheral arterial disease completed attitude items containing 27 bipolar adjectives and open-ended questions on behavioural, normative and control beliefs relating to using the prosthesis. Academic, clinical and patient experts (n?=?12) identified bipolar adjectives with best face validity. In part two, 15 amputees completed three behavioural format questions relating to prosthetic use and were asked to indicate the easiest to answer.

Results:?Following the completion of the attitude items by the amputees and the expert panel review, 5 items remained (Cronbach's alpha?=?0.87) with corrected item-total correlations ranging from 0.43 to 0.83. Modal behavioural beliefs concerned mobility (46.5%), independence (25.6%) and participation restrictions (16.3%), normative beliefs concerned family (33.3%), NHS staff (31.7%), friends (19.1%) and other patients (15.9%) and control beliefs concerned stairs (21.1%), slippery/rough surfaces (28.9%), disabled facilities (54.8%) and people helping (22.6%). In relation to part 2, an exact numerical report of hours and days of prosthetic use was found easiest to answer (73%).

Conclusions:?Based on this qualitative and quantitative development work, the questionnaire contains five attitude items, six behavioural, eight normative, eight control belief items and two self-report questions of the behaviour.  相似文献   
89.

Objectives

The aims of the study were to compare subjective image quality of clinical images obtained with a storage phosphor plate (SPP)-based digital and conventional film-based panoramic system for the visualization of various anatomical structures and to evaluate the effect of various processing algorithms on image interpretation.

Methods

Panoramic radiographs were taken in 42 patients both with film and with a SPP system. SPP images were treated with shadow, sharpen, negative, greyscale sigma and greyscale exponential filters. Four observers subjectively evaluated films and unfiltered and filtered SPP images for the visibility of anatomical structures with various radiodensities as well as for overall image quality on a three-point rating scale. The statistical methods used were Kruskal–Wallis, odds ratio analysis and Cohen''s kappa.

Results

No statistically significant difference was found between film and unfiltered digital images except for low-contrast structures (P > 0.05). Film images were preferred for the visibility of low-contrast structures (P < 0.05). Best overall image quality was obtained with sharpened images (P < 0.05) followed by films and unfiltered digital images. Among all filtered images, sharpened ones received the highest ratings for the visibility of all anatomical structures (P < 0.05). The intra- and interobserver agreement ranged between moderate and substantial and between fair and moderate, respectively.

Conclusions

Film and unfiltered SPP-based panoramic images performed equally well in terms of overall quality; however, films were best for the perception of low-contrast structures. The sharpening filter may be recommended for enhancing SPP panoramic images to improve the visual perception of most of the anatomical structures as well as overall quality.  相似文献   
90.
Marfan syndrome is a clinically and allelic heterogeneous, heritable connective tissue disorder with infrequently reported neuromuscular features. This study is the first to delineate these symptoms in a non-selected population. Neuromuscular involvement was evaluated in 10 Marfan patients through a standardized questionnaire, physical examination, nerve conduction study (NCS), needle electromyography (EMG), muscle ultrasound, laboratory investigation, and muscle biopsy. Existing neuroimages were screened for dural ectasia and spinal meningeal cysts. Twenty healthy controls with similar age distribution completed the questionnaire.
The results showed that various neuromuscular symptoms occur more frequently in the patients. Four older patients reported muscle weakness, five patients had a mild-to-moderate reduction in vibration sense, and all older patients mentioned mild functional impairments. NCS showed axonal polyneuropathy in four and EMG myopathic and neurogenic changes in all patients. Increased echo intensity and atrophy on muscle ultrasound was found in more than half of the patients. Muscle biopsies obtained in two patients showed myopathic changes in the older, female patient.
In conclusion, the majority of Marfan patients exhibited neuromuscular symptoms characterized as myopathy or polyneuropathy or both, and signs of lumbosacral radiculopathy, with symptoms being most pronounced in the older patients. Although meriting corroboration, these findings indicate a need to further the awareness of neuromuscular involvement in this population.  相似文献   
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