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101.
A monoclonal antibody (designated K:1-6F) generated by hybridization of mouse myeloma cells with spleen cells from mice immunized with the erythroleukemic cell line K562 was found by fluorescence-activated cell sorter analysis, dot-blot assay and electroimmunoblotting to bind to a majority of cells in the K562 and HEL erythroleukemic cell lines, to a subset of cells of the erythroid lineage from normal bone marrow, to a subset of cells in all analysed cases (total 10) of erythroleukemia, and weakly to cells from patients with myeloid leukemia. The antibody did not bind to normal erythrocytes, monocytes, T- and B lymphocytes or granulocytes, as well as a panel of human malignant cell lines of hemopoietic origin (HL60, U937, Daudi, Molt-3, RH-L4 and U266). Biochemical characterization of the antigen defined by the antibody suggests that eht epitope is defined by a carbohydrate structure alone or in combination with proteins. Four molecules with Mr 100 kD, 65 kD, 45 kD and 18 kD respectively were immunoprecipitated from Triton X-100 extract of K562 erythroleukemia cells. Neuraminidase did not affect the binding of the antibody, whereas tunicamycin reduced the K:1-6F expression. The K:1-6F Mab was in normal bone marrow found to be specific for erythroid precursor cells and may therefore be useful in examination of normal and leukemic erythropoiesis. 相似文献
102.
The immunomodulating 2-cyanaziridine derivatives BM 12.531 (azimexone) and BM 41.332 have no effects on the total amount of T-lymphocytes in the spleen of mice but ingrease dose-dependently the percentage of Ly1--, 2+, 3+ T-lymphocytes (killer/suppressor) and decrease the percentage of Ly1+, 2--, (helper) cells. These investigations were carried out by means of specific monoclonal antibodies and fluoreqcence-activated cell sorting. The increase in Ly2+-cells is mainly due to increased suppressor activity. 相似文献
103.
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105.
Ann Goetting 《The journal of primary prevention》1994,14(3):169-186
This paper examines delinquency as it relates to family influences. 相似文献
106.
Methyl sulphone metabolites of PCB and DDE were isolated from different tissues of a Baltic grey seal (Halichoerus grypus). Main components in the seal blubber were identified as 3-MeSO2-2,2',4',5,5'-pentaCB, 4-MeSO2-2,2',4',5,5'-pentaCB, 3-MeSO2-p,p'-DDE, 4-MeSO2-2,2',3',4',5-pentaCB and 4-MeSO2-2,2',3,4',5',6-hexaCB. Liver and lung in the seal contained different MeSO2-PCB pattern compared to all other tissues. These levels in the both tissues were estimated to be 28 and 15 ppm (lipid basis) which corresponded to the same level as the PCB. Concentrations of MeSO2-PCB in any tissues of a Yusho patient were low compared to those in the seal. 相似文献
107.
Abstract A previous study of the sensitivity and accuracy of a standardized radiographic technique for the disclosure of root cavities in a cadaver material indicated that it was not possible to perceive small artificial “resorption” cavities. Using the same material, the aim of the present study was to evaluate whether the use of subtraction radiography would improve the detection of root cavities. In an autopsy material of five mandibular blocks each containing two premolars, small, medium, and large cavities were drilled in the cervical, middle, and apical thirds of the proximal and oral root surfaces. Each jaw block was radiographed before (B) and after (A) cavity preparation with three different exposure times resulting in light, medium, and dark film densities. The radiographs were digitized. Digital subtraction was performed between the A- and B images of varying densities by a computer program developed for dental subtraction radiography. Conventional and reverse contrast modes of the subtraction image were assessed independently by four observers. The results showed small inter- and intraobserver differences in diagnostic accuracy for assessment of total number of root cavities. Original film density did not influence the diagnostic performance in the resulting subtraction image. Contrast mode in the subtraction image influenced diagnostic performance as the majority of observers did best with the reverse contrast mode (p<0.05). Some of the small root cavities were disclosed by the subtraction technique, but overall accuracy was not increased compared to conventional radiography. 相似文献
108.
Michael P Hill Erwan Bezard Steven G McGuire Alan R Crossman Jonathan M Brotchie Ann Michel Renee Grimée Henrik Klitgaard 《Movement disorders》2003,18(11):1301-1305
Long-term dopamine replacement therapy of Parkinson's disease leads to the occurrence of dyskinesias. Altered firing patterns of neurons of the internal globus pallidus, involving a pathological synchronization/desynchronization process, may contribute significantly to the genesis of dyskinesia. Levetiracetam, an antiepileptic drug that counteracts neuronal (hyper)synchronization in animal models of epilepsy, was assessed in the MPTP-lesioned marmoset model of Parkinson's disease, after coadministration with (1) levodopa (L-dopa) or (2) ropinirole/L-dopa combination. Oral administration of levetiracetam (13-60 mg/kg) in combination with either L-dopa (12 mg/kg) alone or L-dopa (8 mg/kg)/ropinirole (1.25 mg/kg) treatments was associated with significantly less dyskinesia, in comparison to L-dopa monotherapy during the first hour after administration. Thus, new nondopaminergic treatment strategies targeting normalization of abnormal firing patterns in basal ganglia structures may prove useful as an adjunct to reduce dyskinesia induced by dopamine replacement therapy without affecting its antiparkinsonian action. 相似文献
109.
The study was designed to investigate if modern low dosage combined oral contraceptives were associated with changes in plasma prolactin levels in healthy nulliparous women aged 19–25. Plasma prolactin was not significantly correlated to oral contraceptive use, nor to smoking habits. Plasma prolactin was, however, significantly negatively correlated to time since awakening. A significant two-way interaction on prolactin was also seen between smoking and present oral contraceptive use. In our material the mean values of plasma prolactin were higher in the follicular phase than in the luteal phase, although not significantly. 相似文献
110.
Susan A. Murphy Gillian R. Bentley Mary Ann O'Hanesian 《Statistics in medicine》1995,14(17):1843-1857
This paper concerns the analysis of menstrual data; in particular, methodology to identify variables that contribute to the variability of menstrual cycles both within and between women. The basis for the proposed methodology is a parameterization of the mean length of a menstrual cycle conditional upon the past cycles and covariates. This approach accommodates the length-bias and censoring commonly found in menstrual data. Data from a longitudinal study of menstrual patterns and other variables among Lese women of the Ituri Forest, Zaire, illustrate the methodology. A small simulation illustrates the bias caused by incorrectly deleting the censored cycles. 相似文献