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101.
In vitro preincubation with recombinant granulocyte colony-stimulating factor(rhG-CSF, 100 ng/ml) enhanced the cytotoxicity of 1-beta-D-arabinofuranosylcytosine(Ara-C) in leukemic cells resistant to Ara-C from a patient with biphenotypic leukemia. Treatment of the cells with rhG-CSF resulted in a 17-fold increase in DNA synthesis, 4.6-fold increase in percentage of S-phase, and a two-fold increase in Ara-CTP formation. Maximal effect was observed at 72 h of incubation. Combination chemotherapy with rhG-CSF and Ara-C to the patient showed remarkable cytoreduction. These results indicate that recruitment of resistant leukemic cells in cell kinetic quiescence is inducible by rhG-CSF and that it is possible enhancement of the cytotoxicity to cell cycle-specific drugs such as Ara-C.  相似文献   
102.
The effects of ageing on the oral (gastrointestinal) absorption of d -xylose were investigated by analysing the gastrointestinal disposition after oral administration to young (9 weeks) and old (53 weeks) rats. A linear model assuming first-order gastric emptying followed by first-order intestinal absorption was fitted to remaining fraction vs time profiles for the stomach and small intestine to estimate the gastric emptying rate constant (kg) and the intestinal absorption rate constant (ka). In young and old rats, kg values were 0·087 ± 0·008 and 0·070 ± 0·007 min?1, respectively, and ka values were 0·020 ± 0·002 and 0·018 ± 0·002 min?1 suggesting an insignificant effect on ageing on the rate of oral absorption. The average intestinal lumen volume (Vav) was unchanged with ageing, and so was the apparent intestinal membrane permeability clearance (CLapp) as the product of ka and Vav. However, the small intestinal transit time (Tsi) was suggested to be twice that in older rats (171 min) than in young rats (78 min) by the analysis of gastrointestinal disposition of inulin, a non-absorbable marker. It was also shown that our preceding finding of an increase in the fraction absorbed of D-xylose with ageing can be solely ascribable to the delay in intestinal transit. Thus, among various determinants of oral absorption, only Tsi was found to be altered with ageing. The CLa,app and ka of passively absorbed drugs such as D-xylose may be generally unchanged, and the fraction absorbed may increase with ageing by the delay in intestinal transit.  相似文献   
103.
以制备晶形、粒度、轴比等满足高性能磁粉要求的铁黄为目标,研究了碱法超细α-FeOOH合成的工艺配方和工艺条件对粒子性能的影响,包括碱比、气量、转速、Fe(OH)_2结晶条件、熟化时间等工艺参数的影响规律。重复稳定地制备出三类超微粒α-FeOOH粒子,其粒度分别为0.18、0.28、0.39μm,分布均匀,无枝叉。  相似文献   
104.
曹红  曹军  许燕云 《上海医学》2003,26(7):499-500
目的 研究p53、bcl—2和c—myc在皮肤鳞状细胞癌中的异常表达及其与癌分化程度的关系。方法 应用免疫组织化学S-P法检测58例皮肤鳞状细胞癌中p53、bcl—2和c—myc的表达水平。结果 58例皮肤鳞状细胞癌中p53、bcl-2和c—myc的阳性表达率分别为48.3%、67.2%和32.8%。结论 p53、bcl—2和c—myc异常表达在皮肤鳞状细胞癌的发生、发展中起重要作用,并与皮肤癌的恶性程度有关。  相似文献   
105.
李钧  张泺 《眼科研究》1990,8(3):156-158
应用神经组织化学技术观察了兔角膜NA能神经及AchE阳性神经在角膜损伤后的再生,证实术后1月,两种神经均有再生轴突进入植片;术后3月可见交界区和植床内神经密度明显增加;同时,对术后两种神经再生的功能意义进行了讨论。  相似文献   
106.
To clarify the mechanism of postischaemic delayed cornu Ammonis (CA)-1 neuronal death, we studied correlations among calpain activation and its subcellular localization, the immunoreactivity of phosphatidylinositol 4,5-bisphosphate (PIP2) and Ca2+ mobilization in the monkey hippocampus by two independent experimental approaches: in vivo transient brain ischaemia and in vitro hypoxia-hypoglycaemia of hippocampal acute slices. The CA-1 sector undergoing 20 min of ischaemia in vivo showed microscopically a small number of neuronal deaths on day 1 and almost global neuronal loss on day 5 after ischaemia. Immediately after ischaemia, CA-1 neurons ultrastructurally showed vacuolation and/or disruption of the lysosomes. Western blotting using antibodies against inactivated or activated μ-calpain demonstrated μ-calpain activation specifically in the CA-1 sector immediately after ischaemia. This finding was confirmed in the perikarya of CA-1 neurons by immunohistochemistry. CA-1 neurons on day 1 showed sustained activation of μ-calpain, and increased immunostaining for inactivated and activated forms of μ- and m-calpains and for PIP2. Activated μ-calpain and PIP2 were found to be localized at the vacuolated lysosomal membrane or endoplasmic reticulum and mitochondrial membrane respectively, by immunoelectron microscopy. Calcium imaging data using hippocampal acute slices showed that hypoxia-hypoglycaemia in vitro provoked intense Ca2+ mobilization with increased PIP2 immunostaining specifically in CA-1 neurons. These data suggest that transient brain ischaemia increases intracellular Ca2+ and PIP2 breakdown, which will activate calpain proteolytic activity. Therefore, we suggest that activated calpain at the lysosomal membrane, with the possible release of biodegrading enzyme, will cause postischaemic CA-1 neuronal death.  相似文献   
107.
To evaluate the correlation between the histological grade and the prognosis, we reviewed 100 cases of prostatic cancer according to the Japanese General Rules of Prostatic Cancer (JGRPC) and Gleason grading system. The study led to the following results: (1) There was a close relation between the JGRPC grade and Gleason score (GS). (2) The JGRPC grade and Gleason score were equally concerned with the clinical stage. (3) There were significant differences in survival rate between well and moderately, well and poorly differentiated groups by the JGRPC grading system, and between GS 2-4 and GS 5-7, GS 2-4 and GS 8-10 groups by Gleason score. (4) In proportion to the JGRPC grade, the cancer death rate increased linearly in each stage. (5) When the patients were grouped according to their JGRPC grades of main lesion and accompanied lesion, the cancer death rate increased in the cases with lower differentiated elements. We conclude that the JGRPC grading system is easily comprehensible, and equal with the Gleason grading system to predict the prognosis of prostatic cancer.  相似文献   
108.
Background :
The aim of this study was to investigate the influence of osteoarthritis of lumbar vertebrae on serum bone formation and resorption marker levels of patients with benign prostatic hypertrophy (BPH).
Methods :
Serum levels of carboxyterminal propeptide of type I procollagen (PICP), alkaline phosphatase (ALP), carboxyterminaltelopeptide of type I collagen (ICTP), and prostate-specific antigen (PSA) were examined in 40 patients with BPH, and the presence of osteoarthritis at the lumbar vertebrae of the patients was evaluated by plain x-ray-p.
Results :
Findings of osteoarthritis were observed in 23 of the 40 patients (58%), and 10 of the patients had severe osteoarthritis (involving at least 2 lumbar vertebral bodies). The serum levels of PICP, ALP, ICTP, and PSA of the patients without osteoarthritis findings were not different from those of the patients with osteoarthritis or severe osteoarthritis.
Conclusion :
The influence of osteoarthritis on serum bone formation and resorption marker levels of patients with BPH appears to be rather slight, if there is any influence at all.  相似文献   
109.
The vasodilator effects of C-type natriuretic peptide (CNP) were investigated in isolated rat cerebral arterioles. CNP caused dose-dependent vasodilation, maximally by 10.0±2.2% at 10−6 M. The median effective concentration (EC50) was 5.2×10−10 M. In contrast, atrial natriuretic peptide and B-type natriuretic peptide, other members of the natriuretic peptide family, produced little or no vasodilation. Pretreatment with methylene blue (10−4 M) abolished CNP-induced vasodilation, whereas pretreatment with NG-monomethyl--arginine or indomethacin did not inhibit vasodilation. Thus, CNP is suggested to cause significant vasodilation in cerebral arterioles via a cyclic guanosine monophosphate-dependent mechanism. © 1997 Elsevier Science B.V. All rights reserved.  相似文献   
110.
烧伤血清刺激对大鼠肠上皮细胞结构和粘弹性的影响   总被引:1,自引:0,他引:1  
目的 动态观察烧伤血清对体外肠上皮细胞 (IEC)骨架和细胞生物力学 (粘弹性 )的影响。 方法 培养大鼠肠上皮细胞株IEC 6 ,用烧伤血清刺激后 ,通过细胞骨架免疫组化、细胞ELISA法定量分析以及粘弹性测定技术 ,动态观察IEC致伤前后的变化。 结果 IEC在烧伤血清作用早期 ,骨架蛋白的表达即明显降低 ,微丝、微管蛋白阳性信号减弱 ,细胞粘弹性下降。 结论 细胞骨架的损伤可引起细胞脆性增加、粘弹性下降 ,导致细胞生物力学特性的改变。这种变化 ,可能直接参与烧伤后肠上皮细胞损伤的发生。  相似文献   
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