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2.
采用斑点酶标染色技术对临床疑似恙虫病患者196份血清进行了IgM抗体的检测并作了初步统计分析。总检出率为92.3%;病后3天内检出率为50%,抗体滴度几何平均值(GMT)为226;4-7天检出率为83%,GMT为320;第4周抗体滴度达峰值,GMT为1585,检出率为100%,同时在4周内棋 GMT与发病时间呈正相关。提示应用本法进行IgM抗体的检测对恙虫病的早期诊断和流行病学调查有着重要意义。 相似文献
3.
目的 观察慢性再生障碍性贫血 (CAA)患者骨髓CD3 4+ 细胞凋亡状况 ,探讨CAA可能的发病机制。方法 采用单克隆抗体 -免疫磁珠分离系统 (MACS)分离纯化 39例CAA患者的骨髓CD3 4+ 细胞 ,用DNA末端原位标 (TUNEL)技术分析骨髓CD3 4+ 细胞原位凋亡状况。结果 CAA患者骨髓细胞的凋亡率为 (39.2 4± 12 .70 ) % ,健康对照组为 (8.5 0± 2 .30 ) % ,组间比较差异有显著性 (P <0 .0 1)。凋亡细胞可见核染色质皱缩、凝聚 ,但未见到核碎裂现象及典型的凋亡小体。结论 CAA患者骨髓CD3 4+ 细胞的过度凋亡是其质或 /和量缺陷的原因之一 相似文献
4.
Early Postnatal Changes in the Somatodendritic Morphology of Ankle Flexor Motoneurons in the Rat 总被引:1,自引:0,他引:1
Joanna Dekkers David L. Becker Jeremy E. Cook Roberto Navarrete 《The European journal of neuroscience》1994,6(1):87-97
The development of locomotor function in the rat spans the first 3 postnatal weeks. We have studied morphological features of the soma and dendrites of motoneurons innervating the physiological flexor muscles of the ankle, tibialis anterior and extensor digitorum longus, by intracellular injection in vitro between the first and ninth postnatal days. We obtained serial optical sections of 96 adequately filled motoneurons in whole-mounted hemisected spinal cords by confocal microscopy, projected them onto a single plane and analysed them morphometrically. On the day after birth, the somatodendritic surfaces of most such motoneurons were covered in growth-associated spiny, thorny or hair-like appendages. These had disappeared from the soma by the fourth postnatal day and from most proximal dendrites by day 7, but were still common distally on day 9. During this period there was little or no net growth of either the soma (which was still much smaller than in the adult) or the dendritic tree. A dorsal dendritic bias was present and 'sprays' of long, loosely bundled dorsal dendrites were often seen. The mean number of primary dendrites remained constant at about eight, and their combined diameter was already significantly correlated with mean soma diameter, as in the adult cat. Thus, the critical neonatal period during which these ankle flexor motoneurons are known to change their electrophysiological properties and to be particularly sensitive to interference with neuromuscular interaction is characterized by major changes in the neuronal surface, presumably linked to synaptogenesis. 相似文献
5.
Prognostic factors in myeloma are not only important for allowing comparisons to be made between therapeutic protocols but they also provide us with an insight into the pathophysiology of the disease and important mechanisms which result in disease progression. Prognostic factors in myeloma relate to the inherent proliferative capacity of the malignant clone, tumor bulk, renal function and other factors which reflect tumor host and host tumor interactions. The highly significant effect of the labelling index (LI) suggests that the clonogenic cell is ontologically very close to the malignant plasma cell on which the labelling index is derived. The explanation for the important role of the β2-microglobulin (β2M) level over and above its reflection of renal function is as yet unclear. 相似文献
6.
M. Banyai G. Lupattelli S. R. Li S. Pongratz Q. Yang P. Böck P. Angelberger I. Virgolini 《European journal of nuclear medicine and molecular imaging》1994,21(7):634-639
The binding of radiolabelled lipoproteins, iodine-123-labelled low-density. lipoprotein (LDL) and indium-111-labelled LDL, to peripheral blood mononuclear cells (MNCs) was compared in normolipaemic subjects and in patients with heterozygous familial hypercholesterolaemia (FH). 123I-LDL and 111In-LDL binding to MNCs exhibited high-affinity, highly specific, time- and temperature-dependent binding reaching saturation at concentrations above 50 nM. The number of LDL binding sites (Bmax) was significantly (P<0.01) lower in FH patients (P<0.001; 123I-LDL: Bmax 279±44 ng protein/108MNCs; 111In-LDL: Bmax 309±43 ng protein/108MNCs) as compared with controls (123I-LDL: Bmax 2874±246 ng protein/108 MNCs; 111In-LDL: Bmax 3145±339 ng protein/108 MNCs). The corresponding dissociation constants (K
d) were 16±8 nM for 123I-LDL and 12±6 nM for 123In-LDL in healthy volunteers (123In-LDL vs 111In-LDL, P<0.05). In FH patients, the K
d values were 20±8 nM for 123I-LDL and 16±6 nM for 123In-LDL (P<0.05 vs controls for both 123I-LDL and 111In-LDL). 111In-LDL binding to MNCs was inhibited (IC50) by 30±8 nM in healthy controls and 38±12 nM in FH patients (P<0.05). 123In-LDL binding to MNCs was inhibited (IC50) by 34±8 nM in healthy controls and 46±10 nM in FH patients (P<0.05). Taken together, these results suggest a reduced number of LDL receptors expressed on MNCs from FH patients. We conclude that 111In-LDL and 123I-LDL are equally well suited as a probe of receptor-mediated binding and uptake of LDL. 相似文献
7.
G. Endert U. Franke P. Kleinert 《European journal of nuclear medicine and molecular imaging》1989,15(5):262-264
The lipophilic 99mTc-DPO complex, developed as a myocardial imaging radiopharmaceutical, was used to label leucocytes. After an incubation of 0.1 ml 99mTc-DPO (8 g DMPE*2HCl) with mixed leucocytes in plasma, the labelling efficiency was over 70%. During incubation in 5 ml plasma, a loss of activity was found between 20% (1 h) and 35% (3 h) caused by elution. Disturbances of cell viability could not be found with the help of the chemiluminescence test. The in vivo recovery was determined in three dogs and was 45%–50% (0.5 h), 30%–36% (1 h), and 18%–24% (3 h). Autologous 99mTc-DPO-leucocytes were used on seven patients with suspected osteomyelitis, there were four true negative and three true positive results. The target/nontarget ratio determined by ROI in the positive cases was 1.8 to 2.5 at 3 h after injection. 相似文献
8.
Richard O. Shillaker Graham M. Bell John T. Hodgson Michael D. J. Padgham 《Archives of toxicology》1989,63(4):283-288
Current European Community (Annex V) guidelines recommend the use of 20 test animals in the guinea pig maximisation test for skin sensitisation. The suitability, for classification and labelling purposes, of reducing the number of test animals has been examined by analysing the results of 40 studies submitted to the Health and Safety Executive, and by the use of a mathematical model. Our results suggest that in most cases an experiment with ten test animals can be used to determine satisfactorily whether a substance should be labelled with the risk phrase may cause sensitisation by skin contact. However, serious consideration should be given to the need for additional investigation if two or three of the ten test animals show a sensitisation response. The highest nonirritant concentration of a substance should be used at challenge. Clearer guidance in Annex V on evaluating challenge responses would be beneficial. 相似文献
9.
H Van Dekken E W Schervish J G Pizzolo W R Fair M R Melamed 《The Journal of pathology》1991,164(1):17-22
We have used fluorescent in situ hybridization and simultaneous in vivo bromodeoxyuridine labelling of a solid bladder cancer to examine tumour cell subsets for possible proliferative growth differences. In this dual-labelled preparation, most tumour cell nuclei exhibited monosomy 9, consistent with reported karyotypes of bladder cancer. Incorporated bromodeoxyuridine was visualized with a fluoresceinated antibody in 5-6 per cent of the tumour cells, concordant with S-phase estimates by cell cycle analysis of the flow cytometric DNA histogram. A majority of the bromodeoxyuridine-positive cells also carried the monosomy 9 chromosome abnormality. This is the first report to demonstrate the feasibility of combined in situ hybridization and detection of bromodeoxyuridine incorporated in vivo in human tumour cells in order to provide information on the growth rate of specific subsets of tumour cells identified by chromosomal constitution. 相似文献
10.
F. VanderWerf Majid Aramideh Jan A. Otto Bram W. Ongerboer de Visser 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,121(4):433-441
Functionally and anatomically, the orbicularis oculi (OO) muscle can be subdivided in a pretarsal, a preseptal, and an orbital
portion. In the rhesus monkey, fluorescent and neuronal retrograde tracing experiments were performed in the pretarsal or
the orbital portion of the OO muscle, or both, using fast blue, diamidino yellow, and wheat germ agglutinin-horseradish peroxidase
as tracers. The preseptal portion was not investigated because of close anatomical relationships to the other portions. It
was found that motoneurons innervating the OO muscle are located exclusively within the intermediate subnucleus of the motor
facial nucleus. The upper pretarsal motoneurons show a specific distribution in the dorso-rostral border area of the intermediate
subnucleus, representing a dome-like organization, while lower pretarsal motoneurons are situated more ventrally in the adjacent
area. The pretarsal motoneurons are all located dorsally in the rostral half and the upper part of the caudal half of the
intermediate subnucleus. The upper pretarsal portion is subserved by about one third of the total intermediate motoneuron
population. The size of the upper pretarsal motoneurons is similar to that of the motoneurons of the lower pretarsal portion
of the OO muscle and falls, for the vast majority, into the large motoneuronal range. Motoneurons belonging to the upper and
lower orbital portions are located ventrally and are more randomly distributed in the rostral half of the intermediate subnucleus.
The size of orbital motoneurons varies from small to large. The large fraction of pretarsal motoneurons may reflect the specific
function of the upper pretarsal portion during rapid and highly coordinated movements of the eyelids in different types of
blinking.
Received: 18 September 1997 / Accepted: 13 March 1998 相似文献