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111.
Although B cell leukemias and, recently, T cell leukemias can be identified both by surface marker and molecular analysis, there remains a population of acute undifferentiated leukemias (AUL) that cannot be allocated definitively to a single cell lineage. AUL was diagnosed in nine patients according to stringent criteria. We combined both immunologic and molecular approaches to analyze further the ambiguous origin of AUL cells. Southern blot analysis revealed rearranged Ig heavy-chain genes in seven patients and indicated a biclonal or oligoclonal leukemic cell population in three of them, including one case of AUL with translocation (4;11). Analysis of cell surface markers showed expression of at least one early B cell-associated antigen (BA- 1, BA-2, B4, UL-38) in six of these seven patients, with coexpression of a myeloid antigen (VIM-2) in three patients. Leukemic cells of two other patients neither exhibited Ig chain gene rearrangements nor expressed B cell-associated antigens. T cell receptor beta-chain genes showed germline configuration in all nine cases. Our results demonstrate heterogeneity among AUL patients based on molecular and surface marker analyses and suggest that most AUL blast cells are derived from a precursor cell that shares phenotypic and genotypic characteristics of early B cells with certain surface antigens of myeloid cells, in some cases of AUL more than one abnormal cell clone or subclone may exist, and the cellular origin, at least of some AULs exhibiting t(4;11), may be truly B cell lineage committed. 相似文献
112.
Anterior temporal lobes and hippocampal formations: normative volumetric measurements from MR images in young adults 总被引:25,自引:0,他引:25
Jack CR Jr; Twomey CK; Zinsmeister AR; Sharbrough FW; Petersen RC; Cascino GD 《Radiology》1989,172(2):549-554
Volumes of the right and left anterior temporal lobes and hippocampal formations were measured from magnetic resonance images in 52 healthy volunteers, aged 20-40 years. Subjects were selected by age, sex, and handedness to evaluate possible effect of these variables. Data were normalized for variation in total intracranial volume between individuals. Right-left asymmetry in the volumes of the anterior temporal lobes and hippocampal formations was a normal finding. The anterior temporal lobe of the non-dominant (right) hemisphere was larger than the left by a small (mean right-left difference, 2.3 cm3) but statistically significant amount (P less than .005) in right-handed subjects. No significant effect of age or sex was seen in normalized right or left anterior temporal lobe volume. The right hippocampal formation was larger than the left for all subjects by a small (mean right-left difference, 0.3 cm3) but statistically significant amount (P less than .001). No effect of age, sex, or handedness was seen in normalized hippocampal formation volumes. 相似文献
113.
114.
Anterior cruciate ligament tears: MR imaging compared with arthroscopy and clinical tests 总被引:10,自引:0,他引:10
Seventy-nine magnetic resonance (MR) studies of the knee were reviewed in an evaluation of the ability of MR imaging to demonstrate arthroscopically proved anterior cruciate ligament (ACL) tears. MR findings were also compared with the findings of two commonly applied clinical tests of ACL instability: the Lachman test and the anterior drawer test. The sensitivity of MR imaging was 94% (17 of 18), compared with 78% (14 of 18) for the anterior drawer test and 89% (16 of 18) for the Lachman test. The specificity was 100% for all three. Three MR criteria were applied: irregularity or a wavy contour of the anterior margin of the ligament, high-signal-intensity change within the substance of the ligament on T2-weighted images, and discontinuity of that substance. The sagittal T2-weighted image was especially helpful, producing an "arthrographic" effect, in which the anterior margin of the ACL is outlined by high-signal-intensity joint fluid. By demonstrating ACL and other extrameniscal lesions, MR imaging may help clarify the mechanisms of knee injury. 相似文献
115.
Isaac D Ward Fabíola CR Zucchi Jerrah C Robbins Erin A Falkenberg David M Olson Karen Benzies Gerlinde A Metz 《BMC pregnancy and childbirth》2013,13(Z1):S9
Peripartum events hold the potential to have dramatic effects in the programming of physiology and behaviour of offspring and possibly subsequent generations. Here we have characterized transgenerational changes in rat maternal behaviour as a function of gestational and prenatal stress. Pregnant dams of the parental generation were exposed to stress from days 12-18 (F0-S). Their daughters and grand-daughters were either stressed (F1-SS, F2-SSS) or non-stressed (F1-SN, F2-SNN). Maternal antepartum behaviours were analyzed at a time when pregnant dams usually show a high frequency of tail chasing behaviours. F1-SS, F2-SNN and F2-SSS groups showed a significant reduction in tail chasing behaviours when compared with controls. The effects of multigenerational stress (SSS) slightly exceeded those of transgenerational stress (SNN) and resulted in absence of tail chasing behaviour. These findings suggest that antepartum maternal behaviour in rats is programmed by transgenerational inheritance of stress responses. Thus, altered antepartum maternal behaviour may serve as an indicator of an activated stress response during gestation. 相似文献
116.
Michael P. Lux Christian M. Bayer Christian R. Loehberg Peter A. Fasching Michael G. Schrauder Mayada R. Bani Lothar Häberle Anne Engel Katharina Heusinger Thorsten Tänzer Dragan Radosavac Anton Scharl Ingo Bauerfeind Judith Gesslein Hilde Schulte Brigitte Overbeck-Schulte Matthias W. Beckmann Alexander Hein 《Breast cancer research and treatment》2013,139(2):429-440
Treatment decisions in oncology are based on a balance between the efficacy of therapy and its side effects. Patients with metastases and patients with a limited prognosis are a particular challenge, since communication about the disease situation and the expected therapeutic benefit is difficult not only for patients, but also for physicians. The aim of this study was therefore to compare the benefits expected of therapy by patients and physicians. Questionnaires were sent to 9,000 breast cancer patients and to 6,938 physicians. The questionnaires described 10 cases of breast cancer in the metastatic setting. The patients and physicians were asked to state the treatment benefit they would require to decide for the therapy options chemotherapy, endocrine therapy, antibody therapy, radiotherapy, and bisphosphonates. Additionally, the participants provided data on patient and physician characteristics. Expected treatment benefits were compared between patients and physicians, and influencing factors that modified the expected benefit were identified. Patients expected much greater benefits from the therapies offered than the physicians. For all treatment modalities, about 50 % or more of patients expected more than a 12-month increase in overall survival from all therapies. Among the doctors, this proportion ranged from 7 to 30 %. Among patients, previous experience of side effects and having young children in the family were the strongest influencing factors. Among the doctors, age and level of education had a strong influence on the expected prognostic improvement to indicate a therapy option. As expectations of treatment differ greatly between patients and doctors, a structured approach to solving this conflict is required. There appear to be some indicators that might help address the problem, such as the physicians’ level of training and experience and the patients’ specific social circumstances. 相似文献
117.
118.
Cutaneous pseudolymphomas refer to a group of benign reactive T or B cell lymphoproliferative processes that simulate cutaneous lymphomas. T cell rich angiomatoid polypoid pseudo lymphoma (TRAPP) of the skin is a unique form of T cell rich cutaneous pseudolymphoma. A 13-year-girl presented with an asymptomatic skin colored papule on the right elbow, the biopsy of which revealed features consistent with TRAPP. The dermis showed an infiltrate of lymphocytes, plasma cells, and histiocytes along with prominent vascular channels lined by plump endothelium. An immunohistochemical study showed a predominance of T cells over B cells. The morphological and immunohistochemical features pointed towards the diagnosis of TRAPP. We report this rare entity, only 17 cases of which have been described so far in literature. The differential diagnoses have also been discussed. 相似文献
119.
Recently, using immunohistochemical methods, we surprisingly found that endoplasmic reticulum glucose-6-phosphatase is present in human embryonic and fetal red blood cells (RBCs) but not in adult RBCs. The fact that an endoplasmic reticulum enzyme, whose major site of expression in adults is the liver, is present in human embryonic and fetal RBCs, particularly nucleated cells, indicated that it would be sensible to determine whether these cells also contain other endoplasmic reticulum enzyme systems normally found in adult liver. Therefore, we have studied the expression of other endoplasmic reticulum proteins and found that human embryonic and fetal RBC precursors contain other protein components of the glucose-6- phosphatase system, ie, the phosphate and glucose transport proteins as well as other enzymes (eg, uridine diphosphate- glucuronosyltransferases, cytochrome P450 isozymes, nicotinamide adenine dinucleotide phosphate cytochrome P450 oxidoreductase, and prostaglandin H synthase). In addition, we also found the predominantly cytosolic markers 15-hydroxyprostaglandin dehydrogenase, prostaglandins PGE2 and 13,14-dihydro-15-keto-PGE2. The expression of key enzymes that control glucose production, detoxification of endobiotics and xenobiotics, and the regulation of prostaglandin levels in embryonic and early fetal RBCs means that these cells may have an important role in protecting the developing conceptus before it establishes an efficient circulation and before all tissues fully express their normal complement of these enzymes. 相似文献
120.