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81.
82.
κ-卡拉胶-魔芋多糖复配胶包埋的啤酒酵母细胞,经冻融处理后用于合成胞嘧啶核苷二磷酸胆碱(CDP-胆碱)。结果表明:250mL摇瓶中加入50mL反应液(葡萄糖400mol/L,CMP10mmol/L,磷酸碍碱50mmol/L,K2HPO4-KH2PO4缓冲液100mmol/L,MgSO410mmol/L,pH=8.0),固定化细胞1200g/L,34℃、150r/min下,反应4h后补加400mmol/L葡萄糖,反应8h可使60%以上的CMP转化为CDP-胆碱。反应液经灭菌和添加辅酶I(NAD^ )后,固定化细胞可连续使用4次,CDP-胆碱转化率维持在40%以上。 相似文献
83.
Immature Megakaryocytes in the Mouse: Morphology and quantitation by acetylcholinesterase staining 总被引:10,自引:1,他引:9
Three types of immature megakaryocytes, detected by their morphological properties, have been characterized in bone marrow of normal C57BL/6 mice. Morphological classification of these cells was carried out by determining (1) presence and relative amount of acetylcholinesterase, (2) cell size, (3) nuclear/cytoplasm ratio, and (4) nuclear shape. The immature megakaryocytes were classified as: (A) cells distinguished by a round nucleus (10.6 +/- 1.1 mu diameter; mean +/- SEM), which had the highest nucleus / cytoplasm ratio and lowest content of acetylcholinesterase; (B) cells with an indented nucleus (13.0 +/- 1.9 mu diameter), which had increased acetylcholinesterase content and reduced nucleus/cytoplasm ratio compared to the round-nucleus cell type; and (C) lobed-nucleus cells (14.5 +/- 2.9 mu diameter), which showed further increase in acetylcholinesterase content and reduction in nucleus/cytoplasm ratio. Increased numbers of immature megakaryocytes were detected, indicating that a proportion of these cells are undetected using conventional staining techniques. Based on the observed alterations in size, acetylcholinesterase content, and nuclear complexity, it was concluded that these cells constitute part of a progressive maturation sequence intermediate between the progenitor cell (CFU-Mk) and mature easily recognizable megakaryocytes. 相似文献
84.
目的:探讨舌下含服米索前列醇预防剖宫产产后出血的效果。方法:将妊娠晚期单胎选择性剖宫产者200例随机分为两组,研究组110例,在第二产程末胎头娩出后舌下含服米索400μg,对照组90例,在胎儿娩出后静脉注射催产素20IU,观察产后2h出血量和用米索前后血压及用药后出现的副作用,结果:产后2h内的出血量,研究组与对照组分别为174.43ml和219.73ml,二组比较有显著性差异(P<0.01),用米索前后血压比较,二组无显著性差异(P>0.05),结论:舌下含服前列醇促进子宫收缩作用强于催产素,能减少产后出血,也适用于某些与血管变化有关的高危孕产妇,预防产后出血。 相似文献
85.
目的 探讨高频超声检测小儿腹股沟斜疝腹股沟管扩张程度对于选择手术方式的价值。 方法 回顾分析 4 88例施行单纯疝囊高位结扎手术的小儿腹股沟斜疝超声检测的腹股沟管扩张最大内径 ,分组追踪其术后斜疝复发率。 结果 腹股沟管扩张最大内径 >1.5 cm的一组病例术后复发率明显增高。 结论 高频超声检测腹股沟管扩张最大内径 >1.5 cm的小儿腹股沟斜疝有必要行斜疝修补术 ,减少复发率 ,为临床医师提供有价值的客观指标 相似文献
86.
持续压力超负荷对兔左心室细胞凋亡的影响 总被引:3,自引:1,他引:2
OBJECTIVE: To study the effect of chronic pressure overload on the apoptosis of the left ventricle myocytes in rabbits. METHODS: Rabbit models of chronic pressure overload-induced heart failure were prepared in which dynamic changes of apoptotic myocytes in the left ventricle were observed by way of terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. RESULTS: Only a few apoptotic cells was observed in the sham-operated group, while in the experimental group, the apoptotic left ventricle myocytes significantly increased after operation, presenting a peak level between day 3 and day 7. Seven days after the operation, the apoptotic myocytes began to decrease and till day 14, the apoptotic cell number had been smaller than that measured on day 1. When signs of heart failure set in, the apoptotic myocytes were again increased (P<0.001). CONCLUSION: During chronic pressure overload, myocyte apoptosis in the left ventricle is elevated at the early stages and undulates subsequently, with the peak occurring before hypertrophy is obvious. 相似文献
87.
益肾化浊注射液对慢性肾功能衰竭大鼠残余肾中细胞因子含量的影响 总被引:2,自引:0,他引:2
通过观察益肾化浊注射液对5/6肾切除大鼠残余肾中细胞因子含量的影响,益肾化浊注射液延缓慢性肾功能衰竭(CRF)模型大鼠肾功能减退的作用机理。结果显示:益肾化浊注射液可以降低5/6肾切在鼠血清肌,尿素氮(P<0.01),下调肾组织中白细胞介素-1(IL-1)(P<0.05),白细胞介素-8(IL-8)(P<0.05)及肿瘤坏死因子(TNF)(P<0.05)的总体水平,说明益肾化浊注射液可以通过下调5/6肾切除大鼠残余肾中相关细胞因子含量,抑制促炎细胞因子对肾脏的损害,从而延缓CRF的进展。 相似文献
88.
Two elderly patients, involved in separate motor vehicle accidents, sustained blunt chest injury resulting in rupture of their thoracic aortas. The initial chest radiographs showed the presence of a calcified ring fractured in two places with lateral displacement of a calcified fragment by haematoma. This ‘broken halo sign’ is a radiographic sign not previously well described in the literature. The presence of a disrupted aortic ring in the elderly patient, associated with the appropriate mechanism of injury, should alert the clinician to the potential diagnosis of traumatic rupture of the thoracic aorta (TRTA). 相似文献
89.
Linda Laatsch Thomas Jobe Jerry Sychra Qing Lin Michael Blend 《Brain injury : [BI]》1997,11(12):851-864
Three patients,with known brain injury and neuropsychological impairments, are followed through an individualized cognitive rehabilitation programme and post discharge from the treatment programme. Single Photon Emission Computed Tomography (SPECT) of the brain was employed to evaluate resting relative cerebral blood flow (rCBF) during the process of recovery from brain injury. All patients experienced significant improvements on measures of neuropsychological functioning and improvements in rCBF during this longitudinal study. The specific changes in rCBF appear to be related to the location of the patient s brain injury and strategies particular to cognitive rehabilitation therapy. Continued improvements in rCBF, functional abilities, and cognitive skills were documented in these three cases up to 45 months post brain injury. 相似文献
90.
九十年代中国人群的膳食与营养状况 总被引:84,自引:6,他引:78
九十年代中国人群的膳食与营养状况葛可佑,翟风英,闽怀成,程列,王青,贾凤梅(中国预防医学科学院营养与食品卫生研究所,北京100050)人群的膳食营养状况在一定程度上可以反映一个国家的经济发展和社会文明程度。世界上大多数发达国家及若干发展中国家都在有计... 相似文献