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A cell line, designated RS4;11, was established from the bone marrow of a patient in relapse with an acute leukemia that was characterized by the t(4;11) chromosomal abnormality. The cell line and the patient's fresh leukemic cells both had the t(4;11)(q21;q23) and an isochromosome for the long arm of No. 7. Morphologically, all cells were lymphoid in appearance. Ultrastructurally and cytochemically, approximately 30% of the cells possessed myeloid features. The cells were strongly positive for terminal deoxynucleotidyl transferase. They were HLA-DR positive and expressed surface antigens characteristic for B lineage cells, including those detected by anti-B4, BA-1, BA-2, and PI153/3. Immunoglobulin gene analysis revealed rearrangements of the heavy chain and kappa chain genes. The cells lacked the common acute lymphoblastic leukemia antigen and antigenic markers characteristic of T lineage cells. The cells reacted with the myeloid antibody 1G10 but not with other myeloid monoclonal antibodies. Treatment with 12-O-tetradecanoyl- phorbol-13-acetate induced a monocyte-like phenotype demonstrated by cytochemical, functional, immunologic, and electron microscopic studies. The expression of markers of both early lymphoid and early myeloid cells represents an unusual phenotype and suggests that RS4;11 represents a cell with dual lineage capabilities. To our knowledge, RS4;11 is the first cell line established from t(4;11)-associated acute leukemia.  相似文献   
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Immunologic heterogeneity of diffuse large cell lymphoma   总被引:2,自引:0,他引:2  
The cellular lineage of 57 diffuse large-cell lymphomas (DLCLs) was determined using a panel of monoclonal antibodies directed against lineage-restricted and -associated T, B, and monocyte antigens. The majority (82%) were of B cell lineage as determined by the expression of sig and/or B1, with the remaining 16% being of T cell lineage and 2%, of monocyte-myeloid lineage. By the expression of other B cell- restricted and -associated antigens, two major and two minor subgroups could be identified. These subgroups expressed the following phenotypes: (1) B1+B4+sIG+B2- (51%); (2) B1+B4+sIg+B2+ (29%); (3) B1+B4+sIg-B2+ (10%); and (4) B1+B4-sIg+B2- (10)%. The morphology of transformed lymphocytes, the weak to absent expression of the early B cell antigens B2 and sIgD, and the absence of the late B cell differentiation antigens PCA-1 and PC-1 suggested that these tumors were the neoplastic counterparts of normal B cells at the mid-stages of differentiation. Further support for the notion that B-DLCLs correspond to transformed B lymphocytes was concluded from the observation that B cells could be identified in normal spleen that expressed the cell surface phenotype and morphological appearance of the majority of B- DLCLs.  相似文献   
35.
The class I genes of the major histocompatibility complex of the mouse can be divided into two categories: those encoding the transplantation antigens and those encoding the Qa and Tla antigens. The inbred BALB/c mouse has 28 potential Qa/Tla genes. The sites of tissue expression, developmental regulation, and functions of these genes are virtually unknown. We have used the technique of exon shuffling to construct hybrid genes between each of three Qa region genes (Q5, Q7, and Q8) and two other class I genes (H-2Ld and Q6). The hybrid genes have been transfected into mouse L cells, in which intact transplantation antigen genes generally are expressed and in which intact Qa genes generally are not expressed. Analysis of expression of the hybrid gene constructs indicates that the 5' half of two of the Qa genes (Q5 and Q8) can readily be expressed in the context of a hybrid molecule, whereas the 3' half prevents cell-surface expression. The exon shuffling approach described here will be useful in characterizing Qa/Tla genes and in identifying or producing new reagents to study the Qa/Tla gene products, their tissue distribution, their developmental stages of expression, and, ultimately, their functions.  相似文献   
36.
Background contextLow back pain (LBP) is associated with high health-care utilization and lost productivity. Numerous interventions are routinely used, although few are supported by strong evidence. Cost utility analyses (CUAs) may be helpful to inform decision makers.PurposeTo conduct a systematic review of CUAs of interventions for LBP.Study designSystematic review.MethodsA search strategy combining medical subject headings and free text related to LBP and health economic evaluations was executed in MEDLINE. Cost utility analyses combined with randomized controlled trials for LBP were included. Studies that were published before 1998, non-English, decision analyses, and duplicate reports were excluded. Search results were evaluated by two reviewers, who extracted data independently related to clinical study design, economic study design, direct cost components, utility results, cost results, and CUA results.ResultsThe search produced 319 citations, and of these 15 met eligibility criteria. Most were from the United Kingdom (n=8), published in the past 3 years (n=12), studied chronic LBP or radiculopathy (n=13), and had a follow-up >12 months (n=13). Combined, there were 33 study groups who received a mean 2.1 interventions, most commonly education (n=17), exercise therapy (n=13), spinal manipulation therapy (n=7), surgery (n=7), and usual care from a general practitioner (n=7). Mean baseline utility was 0.57, improving to 0.67 at follow-up; the mean difference in utility improvement between study groups was 0.04. Based on available data and converted to US dollars, the cost per quality-adjusted life year ranged from $304 to $579,527, with a median of $13,015.ConclusionsFew CUAs were identified for LBP, and there was heterogeneity in the interventions compared, direct cost components measured, indirect costs, other methods, and results. Reporting quality was mixed. Currently published CUAs do not provide sufficient information to assist decision makers. Future CUAs should attempt to measure all known direct cost components relevant to LBP, estimate indirect costs such as lost productivity, have a follow-up period sufficient to capture meaningful changes, and clearly report methods and results to facilitate interpretation and comparison.  相似文献   
37.
BACKGROUND: Merkel cell carcinoma is a rare malignant neuroendocrine neoplasm characteristically arising from the dermis of sunlight-exposed skin. It rarely arises outside the skin. OBJECTIVE: We present a patient with primary Merkel cell carcinoma arising from subcutaneous fat, with no involvement of the overlying skin. We describe the clinical manifestations and magnetic resonance imaging (MRI) findings. METHODS: We report a 63-year-old woman with a primary lesion of Merkel cell carcinoma that arose from the subcutaneous fat layer of the left arm. The lesion presented as a subcutaneous nodule with intact overlying skin. MRI showed that the nodular lesion was located entirely in the subcutaneous fat layer, with no involvement of the dermis. Peritumoral infiltration around the lesion and enlarged lymph nodes deep to the lesion were noted. The patient received wide excision of the lesion with dissection of the regional lymph nodes and adjuvant radiotherapy and chemotherapy. RESULTS: Histopathologic examination confirmed the diagnosis of Merkel cell carcinoma with local lymphatic metastasis, and the lesion was completely located in the subcutaneous fat, with no involvement of the dermis. These findings were well correlated with MRI findings. CONCLUSION: Primary Merkel cell carcinoma may arise from the subcutaneous fat and present as an entirely subcutaneous lesion with intact skin. MRI is helpful to evaluate the local extension of the lesion and regional lymphatic metastasis.  相似文献   
38.
ObjectiveThe Recruitment Innovation Center (RIC), partnering with the Trial Innovation Network and institutions in the National Institutes of Health-sponsored Clinical and Translational Science Awards (CTSA) Program, aimed to develop a service line to retrieve study population estimates from electronic health record (EHR) systems for use in selecting enrollment sites for multicenter clinical trials. Our goal was to create and field-test a low burden, low tech, and high-yield method.Materials and MethodsIn building this service line, the RIC strove to complement, rather than replace, CTSA hubs’ existing cohort assessment tools. For each new EHR cohort request, we work with the investigator to develop a computable phenotype algorithm that targets the desired population. CTSA hubs run the phenotype query and return results using a standardized survey. We provide a comprehensive report to the investigator to assist in study site selection.ResultsFrom 2017 to 2020, the RIC developed and socialized 36 phenotype-dependent cohort requests on behalf of investigators. The average response rate to these requests was 73%.DiscussionAchieving enrollment goals in a multicenter clinical trial requires that researchers identify study sites that will provide sufficient enrollment. The fast and flexible method the RIC has developed, with CTSA feedback, allows hubs to query their EHR using a generalizable, vetted phenotype algorithm to produce reliable counts of potentially eligible study participants.ConclusionThe RIC’s EHR cohort assessment process for evaluating sites for multicenter trials has been shown to be efficient and helpful. The model may be replicated for use by other programs.  相似文献   
39.
0 引言 腹泻标本中同时检出类志贺邻单胞菌和豚鼠气单胞菌 ,在国内尚未见报道 .现报告如下 .1 临床资料 患者 ,女 ,45岁 .主诉于 12 h前因食不洁冷冻鱼类食品后 ,出现腹痛伴腹泻 ,为黄色稀水便转为血水样便 ,9次 / d,每次量约 2 0 0 m L.伴轻度乏力、恶心、里急后重 .腹痛以上腹部及左下腹部为著 ,呈持续隐痛伴有阵发性加重 .于2 0 0 0 - 0 3- 2 7就诊 .体检 :T37.2℃ ,P78次 / min,R16次 /min,BP13/ 8KPa.实验室检查 :WBC10 .8× 10 9· L- 1 ,N0 .84,L 0 .16 .大便常规 :RBC +++/ HP,WBC 3- 9/ HP,便隐血阳性 .取粪便送检做…  相似文献   
40.
Hardy  DC; Murphy  WA; Siegel  BA; Reid  IR; Whyte  MP 《Radiology》1989,171(2):403-414
The radiologic studies of 38 essentially untreated adults with X-linked hypophosphatemia (XLH) were reviewed to determine the prevalence of radiologic features, to compare the findings in men and in women, and to elucidate the natural history of the disease by comparing the findings in young, intermediate-age, and older patients. Bone-reinforcement lines were common, but no characteristic mineral mass alteration was established. Looser zones were more prevalent in older subjects. Osteoarthritis was common, occurring in the ankles, knees, feet, sacroiliac joints, and wrists. Enthesopathy was infrequent in the younger group but was present in every member of the intermediate and older groups and was often accompanied by extra ossicles. Curvatures of the lower-extremity long bones were common in all age groups. Three new skeletal alterations in XLH were found to be common: flaring of the iliac wings, trapezoidal distal femoral condyles, and alterations in talar morphology, including shortening of the talar neck and flattening of the talar dome. Technetium-99m methylene diphosphonate scintigrams of 17 subjects were often abnormal, depicting bowing deformity and focal tracer accumulation in diaphyseal cortices and in periarticular and extraarticular regions. The mean metabolic index was moderately elevated (4.0). Both radiographic and scintigraphic findings were more severe in men, consistent with hemizygosity. The natural history of untreated XLH in both sexes is characterized by the development of a variety of age-related skeletal abnormalities during adulthood.  相似文献   
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