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991.
992.
F. M. RAAPHORST R. LANGLOIS VAN DEN BERGH J. L. M. WAAIJER J. M. VOSSEN & M. J. D. VAN TOL 《Scandinavian journal of immunology》1997,46(3):292-297
Fetal B lymphocytes in mice and humans use a limited number of the available VH gene segments. Mouse fetal B cells primarily utilize 3' VH elements, suggesting that the localization of these elements determines their rearrangement frequency. The previously reported non-random usage of human VH genes has been more difficult to explain. In this study the authors analysed the expression of the most proximal 3' human VH element (VH 6) using a monoclonal antibody (JE-6). VH 6 expression was assessed in various B cell differentiation stages from fetal liver, bone marrow and spleen at 12–20 weeks of gestation. The authors demonstrate that the level of VH 6 expression does not exceed a stochastic usage frequency. This suggests that the localization of VH 6 does not significantly promote its expression during human fetal life, and that other factors must affect the usage of VH genes during human fetal development. 相似文献
993.
Spleen sizing by ultrasound in polycythaemia and thrombocythaemia: comparison with SPECT 总被引:3,自引:1,他引:2
M. Messinezy L. M. MacDonald T. O. Nunan N. B. Westwood S. Chinn & T. C. Pearson 《British journal of haematology》1997,98(1):103-107
Detection of non-palpable early splenic enlargement may aid diagnosis of primary polycythaemia (PP) and primary thrombocythaemia (PT). In this study linear spleen sizing by ultrasound has been compared with spleen volume estimation by single photon emission computerized tomography (SPECT) in 26 patients. Spleen length by ultrasound correlated well with SPECT volume estimation.
Ultrasound spleen length was also measured in 60 normal control subjects where the upper limit of the 95% reference range was 11.6 cm. Changes in spleen length with both age and body weight were substantial and overshadowed the imperfect reproducibility of this method. Therefore, interpretation of an individual's measured spleen length should be in relation to that predicted for adults of the same age and weight, particularly at the extremes of the younger, heavier patients and also the older, lighter patients.
Ultrasound spleen lengths of different patient groups (21 PP, 26 PT, 17 idiopathic erythrocytosis, 12 secondary polycythaemia, nine apparent polycythaemia) were compared both using the measured overall reference range and the differences from the values predicted for their age and weight. The comparison showed that almost all patients with PP whose spleens were not palpable had spleen lengths greater than the upper limit for the normal control group, but separation from the other patient groups was incomplete.
Detection of non-palpable splenomegaly by ultrasound length should remain a 'minor' criterion amongst the 'proposed modified diagnostic criteria' of PP. 相似文献
Ultrasound spleen length was also measured in 60 normal control subjects where the upper limit of the 95% reference range was 11.6 cm. Changes in spleen length with both age and body weight were substantial and overshadowed the imperfect reproducibility of this method. Therefore, interpretation of an individual's measured spleen length should be in relation to that predicted for adults of the same age and weight, particularly at the extremes of the younger, heavier patients and also the older, lighter patients.
Ultrasound spleen lengths of different patient groups (21 PP, 26 PT, 17 idiopathic erythrocytosis, 12 secondary polycythaemia, nine apparent polycythaemia) were compared both using the measured overall reference range and the differences from the values predicted for their age and weight. The comparison showed that almost all patients with PP whose spleens were not palpable had spleen lengths greater than the upper limit for the normal control group, but separation from the other patient groups was incomplete.
Detection of non-palpable splenomegaly by ultrasound length should remain a 'minor' criterion amongst the 'proposed modified diagnostic criteria' of PP. 相似文献
994.
995.
G. V. Petrova V. A. Adarichev A. A. Krivenko G. S. Dymshits A. L. Markel' G. S. Yakobson 《Bulletin of experimental biology and medicine》1997,124(2):773-775
Sensitivity of normotensive Wistar rats and NISAG rats (with hereditary arterial hypertension) to heat stress is compared
at the organism and cell levels. High temperature sensitivity of NISAG rats correlates with a low content of the main heat
shock protein HSP70. This relationship can serve as a biochemical marker of predisposition to arterial hypertension.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 8, pp. 171–173, August, 1997 相似文献
996.
997.
目的 检测亚硒酸钠是否能够削弱或解除顺铂对植物血球凝激素(PHA)刺激的人体外周血淋巴细胞的增殖抑制。方法 用顺铂和亚硒酸钠单独或联合处理PHA刺激的人体外周血淋巴细胞,顺铂(0.05,0.20,0.50mg/L)在细胞培养24h时加入,亚硒酸钠(0.05mg/L)在不同处理中分别在细胞培养开始时加入或与顺铂同时加入;培养72h后检测转化淋巴细胞的有丝分裂指数。结果0.05mg/L亚硒酸钠在培养开始时加入,PHA刺激转化的淋巴细胞有丝分裂指数较对照增长42.8%(P<0.05),与顺铂同时加入,有丝分裂指数增长13.7%(P>0.05)。0.05与0.20mg/L顺铂处理细胞,有丝分裂指数未发生显性改变,当顺铂剂量为0.50mg/L时,细胞有丝分裂指数较对照降低54.5%(P<0.001)。亚硒酸钠预处理细胞可以解除0.50mg/L顺铂所致的细胞增殖抑制,使有丝分裂指数恢复正常,但亚硒酸钠与顺铂同时加入时,被顺铂抑制的有丝分裂指数只能部分提高。结论0.05mg/L亚硒酸钠单独作用于淋巴细胞可直接促进细胞增殖,与顺铂联合处理细胞时,可降低顺铂毒性,拮抗顺铂的抗增殖作用。亚硒酸钠在细胞培养开始时加入培养体系效果更佳。 相似文献
998.
A case-control study of squamous cell carcinoma of the upper aerodigestive tract conducted in Heidelberg and Giessen (FRG) provided information on occupational factors in 200 patients and 800 controls (adjusted to sex, age and area of living; 4:1 matched design). The number of subjects exposed to wood dusts, organic chemicals, coal products or to cement was significantly elevated in the tumour group. An increased risk for head and neck cancer was observed after exposition to wood dust (RR = 2,2), organic compounds (RR = 2,4), coal products (RR = 2,7) and especially to cement (RR = 4,4). The cancer risk due to cement exposition showed a positive correlation to the duration of exposition and remained significantly elevated after adjustment for alcohol and tobacco consumption. 相似文献
999.
J H Kranzler 《Journal of clinical psychology》1991,47(5):691-697
Results of an hierarchical factor analysis with university students (N = 101) do not support the construct validity of the Multidimensional Aptitude Battery (MAB). Although the MAB Full Scale IQ seems to be a valid measure of general mental ability, the construct validity of the Verbal and Performance scale IQs is not supported. Therefore, the Verbal and Performance IQs should be interpreted with caution, if at all. In addition, re-analysis of previous investigations of the MAB underscores the importance of ascertaining the reading level of subjects prior to the administration of the MAB. Marginal reading proficiency, especially on a timed paper-and-pencil test such as the MAB, will confound results. 相似文献
1000.