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991.
The cell-surface antigen CD45 is a complex family of high-molecular-weight glycoproteins expressed on all lymphohematopoietic cells, but not in the same molecular isoform. This antigen complex is known to exhibit protein tyrosine phosphatase (PTPase) activity and appears to have a role in regulation of cell differentiation. In that CD45 expression parallels stages of differentiation in normal bone marrow B cells, it was of interest to evaluate this process in malignant B cells. Monoclonal antibodies (MoAbs) were used to investigate the quantitative expression of CD45 and CD45RA on the B cells of lymphoid leukemias. Employing standardized flow cytometric methods, it was found that the fluorescence intensity (FI) of immunostained malignant B cells, as a reflection of the antigen content, demonstrated correlations with the putative stage of cell differentiation for malignancies at the earlier stages, but at the later stages, a progressive loss of CD45 was observed. Since this antigen family has been found to display PTPase activity, further investigation of CD45 alterations in malignancies may provide insight into potential regulatory disturbances. 相似文献
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Magnetic resonance (MR) imaging studies of the head and neck (excluding the brain) were obtained in 49 children believed to have lesions of the head and neck. Seven children had normal images; in the remaining 42, lesions were divided into four categories: midline lesions, lesions of symmetric paired structures, facial lesions, and nasopharyngeal and oropharyngeal lesions. All entities were well delineated by MR imaging. The imaging planes and sequences chosen depended on the suspected abnormality. Midline lesions were best imaged in the sagittal plane, lesions of paired structures and the face in the axial or coronal planes, and nasopharyngeal and oropharyngeal lesions in the axial or sagittal planes. Intracranial extension of head and neck neoplasms was best evaluated in the coronal plane. Surface coils provided better resolution and were thus more useful in evaluating small superficial lesions; head or body coils were more useful in defining the extent of large lesions. T2-weighted images provided better differentiation between normal and tumor tissue in patients with head and neck neoplasms. 相似文献
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997.
Protective monoclonal antibodies to Chlamydia trachomatis serovar- and serogroup-specific major outer membrane protein determinants. 总被引:30,自引:25,他引:5
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Monoclonal antibodies exhibiting Chlamydia trachomatis serovar specificity (serovar A, B-Ba, or C) and serogroup specificity (B, intermediate, or C serogroup) were produced and characterized. These antibodies reacted with the major outer membrane protein, recognized epitopes located at the chlamydial cell surface, and passively neutralized chlamydial toxicity for mice. The antibodies should be useful reagents for defining the molecular structure of these protective epitopes, a necessary step toward the development of a subunit or recombinant C. trachomatis vaccine. 相似文献
998.
This paper outlines the way in which a focus group approach was used to involve service users in the possible reconfiguration of follow-up services for breast cancer patients at a North London hospital. The focus group was used to identify the priority issues for users and the development of an objective questionnaire, to survey all current service users. Within the National Health Service (NHS) the concept of user involvement has been embodied in contemporary health policy, and has become an important constituent of current policy direction. This study was the first stage of a larger stakeholder project that aimed to involve service users and clinicians in developing a new model of breast cancer follow-up service. From the focus group emerged five key themes around breast cancer follow up. They were: The need for reassurance after the diagnosis of cancer. Continuity of care. Privacy and dignity and other elements of the examination technique. Information and the detection of new symptoms. The opportunity to discuss feelings and worries. In this paper, the nature of breast cancer follow-up services is outlined, and the difficulties associated with such services are discussed. The background to user involvement within the United Kingdom is explored, and the strategies that have previously been used are considered. The practical issues involved in using the focus group approach are examined, and the experience of using such an approach is outlined in this study. The involvement of service users as a key stakeholder in the process of planning change, through a participatory research strategy, ensured that their voices were heard alongside those of both hospital and primary care staff. 相似文献
999.
The induction of hepatic ornithine decarboxylase (ODC) activity in rat livers by the potato glycoalkaloids alpha-solanine, alpha-chaconine, and their aglycone solanidine, has been studied. Ip administration of alpha-solanine at 7.5, 15 and 30 mg/kg body weight produced markedly elevated enzyme activity at 4 hr after treatment, with a linear dose response. The increase was four-fold at the lowest dose administered to 12-fold at the highest. ODC activity was measured at 1, 2, 3, 4, 5, 6, 8, and 24hr after alpha-solanine was given. A statistically significant increase in enzyme activity was evident at 3 hr after treatment; maximal activity occurred at 5 hr and was approximately 12 times greater than the dimethylsulphoxide (DMSO) control level. Elevated activities persisted for several hours, decreasing to about one-third of the maximal level at 8 hr. The relative effects of alpha-solanine, alpha-chaconine and solanidine on ODC activities were studied at 4 hr using an equimolar dose of 17 mM/kg body weight. ODC activity induced by alpha-chaconine was higher than that induced by alpha-solanine; the latter activity was two-thirds that of the former. The aglycone solanidine did not induce any increase in activity compared with the DMSO control. ODC activity with dexamethasone, a glucocorticoid, at 4 mg/kg body weight, followed a pattern similar to that of alpha-solanine. However, maximal activity occurred slightly earlier at 4 hr after treatment. The results show that the extent of induced ODC activity depends on the structure of the potato alkaloid. 相似文献
1000.
Marie Diener-West Sandra M Reynolds Donna J Agugliaro Robert Caldwell Kristi Cumming John D Earle Donna L Green Barbara S Hawkins James Hayman Ishmael Jaiyesimi John M Kirkwood Wui-Jin Koh Dennis M Robertson John M Shaw Jonni Thoma 《Journal of clinical oncology》2004,22(12):2438-2444
PURPOSE: To describe the predictive value of liver function tests (LFTs), chest x-ray, and diagnostic imaging for detecting melanoma metastasis during routine follow-up after treatment for choroidal melanoma. MATERIALS AND METHODS: Prospective longitudinal follow-up of patients enrolled onto two randomized trials was conducted by the Collaborative Ocular Melanoma Study (COMS) Group. Baseline and annual or semiannual systemic and laboratory evaluations were performed according to a standard protocol for 2320 patients enrolled on the COMS. RESULTS: COMS patients were screened annually for metastasis and new cancers using LFTs (alkaline phosphatase, AST, ALT, or bilirubin). Elevated findings (1.5 to 2 times upper limit of normal) on LFT prompted a diagnostic or imaging test to confirm or rule out cancer recurrence. Of 714 patients with clinical reports of metastasis, 675 patients died. Of these 675 patients, all but four had either histopathologically confirmed or clinically suspected metastatic melanoma present at the time of death. Among all patients, the 5-year cumulative diagnosis rate of metastatic melanoma was 24% (95% CI, 22% to 27%). Based on all patients with reported metastasis, the sensitivity, specificity, positive predictive value and negative predictive value associated with at least one abnormal LFT before first diagnosis of metastasis at any site was 14.7%, 92.3%, 45.7% and 71.0%, respectively. CONCLUSION: Use of LFTs results followed by diagnostic tests has high specificity and predictive values but low sensitivity. Better tests are needed to identify earlier metastatic disease associated with choroidal melanoma. 相似文献