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排序方式: 共有852条查询结果,搜索用时 15 毫秒
91.
92.
CT-guided intraarterial chemotherapy in locally advanced tumors 总被引:1,自引:0,他引:1
Gorich J; Rilinger N; Sokiranski R; Vogel J; Wikstrom M; Kramer S; Merkle E; Rieber A; Brambs HJ 《Radiology》1996,199(2):567
93.
94.
Eum KD Li J Jhun HJ Park JT Tak SW Karasek R Cho SI 《International archives of occupational and environmental health》2007,80(6):497-504
Objectives To test the validity and reliability of selected scales, namely, decision latitude, psychological job demand, social support,
job insecurity, and macro-level decision latitude from the Korean version of the job content questionnaire (K-JCQ), as part
of a psychosocial epidemiological study among university hospital workers.
Methods K-JCQ was developed by translation and back translation complying with the JCQ usage policy, and its psychometric properties
were explored among 338 workers (290 females and 48 males) in a university hospital in Korea. Internal consistency was examined
using Cronbach’s alpha correlation coefficients. Factorial validity was tested using exploratory factor analysis. Pearson’s
correlation coefficients were used for test–retest reliability among a subset of 157 workers who responded to a repeat survey.
Criterion-related validity was assessed by investigating the effects of the scales on job satisfaction and self-identity through
work in multiple regression models.
Results Cronbach’s alpha for all selected scales was higher than 0.6, except for job insecurity (0.53) and macro-level decision authority
(0.52), indicating appropriate internal consistency. Correlation coefficients between test and retest scales of decision latitude,
psychological job demand, and social support were 0.60, 0.41, and 0.35, respectively. Exploratory factor analysis found three-
and four-factor models, i.e., with and without macro-level decision latitude, respectively, closely corresponding to the theoretical
constructs. High levels of decision latitude and social support, and low levels of psychological job demand and job insecurity
were significantly associated with high level of job satisfaction. Higher self-identity through work was positively related
to decision latitude and social support.
Conclusions These findings suggest that K-JCQ is valid and reliable for assessing psychosocial job stress among Korean workers. Macro-level
decision latitude showed a separate factorial structure and was strongly associated with task-level decision latitude. 相似文献
95.
96.
97.
Batard P; Sansilvestri P; Scheinecker C; Knapp W; Debili N; Vainchenker W; Buhring HJ; Monier MN; Kukk E; Partanen J; Matikainen MT; Alitalo R; Hatzfeld J; Alitalo K 《Blood》1996,87(6):2212-2220
Growth factor receptors in human hematopoietic progenitor cells have become the focus of intense interest, because they may provide tools for the monitoring, enrichment, and expansion of stem cells. We have shown earlier that the Tie receptor tyrosine kinase is expressed in erythroid and megakaryoblastic human leukemia cell lines, in the blood islands of the yolk sac, and in endothelial cells starting from day 8.0 of mouse development. Here, the expression of Tie was studied in human hematopoietic cells of various sources. Peripheral blood mononuclear cells were Tie-. However, a large fraction of CD34+ cells from umbilical cord blood (UCB) and bone marrow (BM) expressed tie protein and mRNA. On average, 64% of the fluorescence-activated cell sorting- gated UCB CD34+ cells including CD38- cells and a fraction of cells expressing low levels of c-Kit were Tie+. Also, 30% to 60% of BM CD34+ cells were Tie+, including most of the BM CD34+CD38-, CD34+Thy-1+, and CD34+HLA-DR- cells. Under culture conditions allowing myeloid, erythroid, and/or megakaryocytic differentiation, purified UCB CD34+ cells lost Tie mRNA and protein expression concomitantly with that of CD34; however, a significant fraction of cells expressed Tie during megakaryocytic differentiation. These data suggest that, in humans, the Tie receptor and presumably its ligand may function at an early stage of hematopoietic cell differentiation. 相似文献
98.
Identification of a cellular polypeptide that distinguishes between acute lymphoblastic leukemia in infants and in older children 总被引:1,自引:0,他引:1
Hanash SM; Kuick R; Strahler J; Richardson B; Reaman G; Stoolman L; Hanson C; Nichols D; Tueche HJ 《Blood》1989,73(2):527-532
We analyzed the polypeptide pattern of leukemic cells of infants and older children with acute lymphoblastic leukemia (ALL), using two- dimensional polyacrylamide gel electrophoresis (PAGE). Patterns were analyzed for the occurrence of a previously detected cytosolic polypeptide, designated L3. Quantitative analysis of L3 in 12 infants and 91 older children with non-T ALL indicated lack of expression of polypeptide L3 in leukemic cells of infants which, in most cases, expressed HLA-DR and CD19 and lacked CD10. Quantitative analysis of L3 in relation to cell surface marker expression revealed that L3 was limited in its occurrence to non-T ALL and was not coordinately expressed with any of the surface markers included in the study. Among patients in the HLA-DR-positive, CD19-positive, and CD10-negative group, different levels of polypeptide L3 were observed between infants and older children. These results indicate differences in leukemic cell constituents between infants and older children with ALL and an otherwise similar cell surface marker phenotype. 相似文献
99.
Hooijkaas H; Hahlen K; Adriaansen HJ; Dekker I; van Zanen GE; van Dongen JJ 《Blood》1989,74(1):416-422
We investigated whether an indirect nuclear terminal deoxynucleotidyl transferase (TdT) immunofluorescence (IF) assay on single cells present in the cerebrospinal fluid (CSF) is more effective than conventional cytomorphology for early detection or exclusion of (minimal) meningeal leukemic infiltration in patients with a TdT+ malignancy. During a 5- year follow-up study, 1,661 consecutive CSF samples from 113 children with a TdT+ acute lymphoblastic leukemia (ALL) (n = 100), a TdT+ acute nonlymphoblastic leukemia (ANLL) (n = 8), or a TdT+ non-Hodgkin's lymphoma (NHL) (n = 5) were analyzed. In 1,511 (91.9%) of 1,643 evaluable CSF samples, the positive and negative findings of both cytomorphology and the TdT-IF assay were concordant. In 47 (2.9%) samples from 28 patients, the cytomorphology was suspect while the TdT- IF assay was negative; follow-up as long as 58 months revealed no CNS leukemia in any patient. In 85 (5.2%) samples, cytomorphology was negative (n = 70) or suspect (n = 15) but TdT+ cells were detected. RBC contamination seriously hampered evaluation in 31 of these 85 samples. From the remaining 54 TdT+ samples from 29 patients, 40 samples preceded overt CNS leukemia in 20 patients. Two consecutive findings of TdT+ cells in the CSF were always followed by overt CNS leukemia. At initial diagnosis, 11 children had TdT+ cells in their RBC-free CSF. In one of these children, morphology was suspect; a repeated lumbar puncture was positive on both assays. Thus, initial CNS leukemia was diagnosed. In the other ten children, morphology was negative. In six of them, CNS leukemia was diagnosed 2 to 20 months later. In 32 other children examined at initial diagnosis, neither TdT+ cells nor blasts were observed in the CSF. In none of these patients was a CNS leukemia diagnosed after a follow-up of 2.5 to 57 months (median 24 months). In 207 control CSF samples from 58 children with TdT- oncologic, hematologic, or infectious diseases, no TdT+ cells could be detected. The TdT-IF assay is easy to perform and is a more reliable diagnostic tool for detection of CNS leukemia at an early stage than is cytomorphology. At initial diagnosis, the finding of Tdt+ cells in a RBC-free CSF sample with a negative cytomorphology is highly predictive for development of overt CNS leukemia. 相似文献
100.
A patient with plasma cell myeloma producing only Bence Jones lambda protein was found to have pale intranuclear inclusions in the majority of the bone marrow plasma cells. These inclusions, previously undescribed in myeloma patients producing only Bence Jones protein, contained Bence Jones lambda protein, were non-electron dense, bound by a single membrane, and contained no cytoplasmic structures. Intracytoplasmic inclusions were not present, and the perinuclear cistern was not dilated. Thus, the inclusions may represent intranuclear protein synthesis with anomalous release in the abnormal cells. 相似文献