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991.
The purpose of the present study was to determine whether a hypotonic additive containing a low concentration of glycerol as a membrane permeable solute would improve the liquid storage of red blood cells (RBCs). Packed RBCs were stored either with 200 ml of an experimental additive solution, EAS 25, containing (m M ): glycerol 150, adenine 2, glucose 110, mannitol 55, and NaCl 50, or with 100 ml/unit of a conventional additive solution Adsol®. The results show that the adenosine triphosphate values, hemolysis, potassium leakage, and the morphology scores of RBCs were significantly better with EAS 25 than with Adsol up to 84 days of storage. The ATP values were significantly different only after the first 42 days of storage. The mean corpuscular volumes (MCVs) of the RBCs were significantly higher throughout in the experimental additive accompanied by decreased microvesiculation as compared to Adsol. The total microvesicle membrane protein shed by 100 ml of RBCs was 47.92±12.31 mg in Adsol and 18.96±5.49 mg in EAS 25 (p<0.001). The larger MCVs of the RBCs in EAS 25 may have a favorable effect on maintaining membrane integrity by decreasing the loss of membrane by microvesiculation.  相似文献   
992.
氟骨症性椎管狭窄症的手术治疗   总被引:2,自引:1,他引:1  
1987~1990年手术治疗氟骨症性椎管狭窄症100例。包括颈椎9例,胸椎8例,腰、骶椎83例。术后随访1~4年,复查结果:临床治愈93例(93%):显效3例(3%)、有效3例(3%)、无效1例(1%)。手术原则是彻底减压,因氟骨症具有椎骨及其骨周组织严重退变、异化和骨化的临床病理特点,故在胸、腰椎减压术后,一般不影响其稳定性,在颈椎施行双开式或单开式椎管扩大加植骨融合术,则可收减压、稳定及防止或减少椎板间隙瘢痕狭窄的效果。  相似文献   
993.
994.
30例肝硬化食管静脉曲张破裂大出血患者,用垂体后叶素0.2~0.4U/min连续静脉滴注和硝酸甘油含服联合治疗。结果表明,近期止血有效申达80%,死亡率10%;无一例出现严重心绞痛和心电图异常。  相似文献   
995.
O6-Alkylguanine--DNA alkyltransferase (AGT) is a protein which removes the promutagenic O6-alkylguanine lesion induced in DNA by alkylating agents. Our results demonstrate that freshly isolated organoids from reduction mammoplasty specimens contain significant levels of AGT activity. AGT activity in breast epithelial cells shows interindividual variation. Constitutive levels of AGT activity remain unchanged during short-term serum-free culture of breast epithelial cells inside three-dimensional rat-tail collagen gel matrix. In the present study, we optimized conditions for depleting AGT activity in human breast epithelial cells cultured in three-dimensional collagen gel matrix using O6-methylguanine and O6-benzylguanine which are substrates for AGT. AGT activity was efficiently inactivated by exposure of cells to O6-methylguanine or O6-benzylguanine. Inactivation with O6-benzylguanine was more rapid, of greater magnitude and consistency and occurred at lower concentrations than with O6-methylguanine. Near-complete inactivation (> 99.5%) of AGT activity was reproducibly achieved with 50 microM O6-benzylguanine. In contrast, 500 microM O6-methylguanine was needed to obtain a maximal effect and this reduced AGT activity by only 53-93% of control. Within 30 min of adding the free base, 50 microM O6-benzylguanine depleted 95% of the levels of AGT compared to 30% inhibition with 500 microM O6-methylguanine. The profile for restoration of AGT activity was different following a 24 h incubation and subsequent removal of each of the guanine derivatives. AGT activity levels remained undetectable for at least 2 days after removal of 50 microM O6-benzylguanine from the medium and recovered to only 53% of control values after an additional 3 days. AGT activity levels remained undetectable for at least 2 days after removal of 50 microM O6-benzylguanine from the medium and recovered to only 53% of control values after an additional 3 days. In contrast, following removal of 500 microM O6-methylguanine, the activity was restored from its nadir of 16% of control values reaching pretreatment levels after 5 days. These results suggest that treatment with O6-benzylguanine may be used to modulate the incidence of transforming mutations in cultured human breast epithelial cells treated with chemical carcinogens which give rise to O6-alkylguanine adducts.  相似文献   
996.
Summary T cell activation and proliferation via CD3-TCR complex were investigated by lymphocyte DNA synthesis in vitro. Several interfering factors were also discussed. The result indicated that lymphocyte activation and proliferation are calciumdependent. A rise of cytoplasmic free Ca2+ quickly following activation with CD3 McAb is mainly due to intracellular mobilization of Ca2+, while lymphocyte proliferation needs both intracellular mobilization of Ca2+ as well as influx of extracellular Ca2+. It was confirmed that CTX sensitive G protein plays a role in regulating T cell proliferation by pretreatment with CTX suppressing lymphocyte3H-TdR incorporation obviously. PLC and PKC inhibitor neomycin and P. S. S could also decrease T cell proliferation.  相似文献   
997.
用遗传流行病学调查对245例先天性耳前瘘管进行了系谱分析。揭示了该病的遗传特征为“常染色体显性遗传伴外显不全”,本调查还发现该病的另一特征,即患病体侧的家族一致性。  相似文献   
998.
From July 1989, to June 1996, 160 patients with congenital bile duct dilatation (CBD) were treated at our institution. The incidence of CBD at our institution has increased annually. In approximately 90% of patients with CBD there was associated anomalous arrangement of the pancreaticobiliary ductal system, and we concluded that this was one of the main causes of CBD. Pediatric endoscopic retrograde cholangiopancreatography was first introduced to China in 1989, and has been successfully performed in 90.2% of 92 patients at our institution. We found that age at diagnosis was closely related to the subtype, complications, and mortality of CBD. The subtype also correlated with the presenting symptoms. One hundred and forty-seven of the 160 patients underwent surgery. Of these 147 patients, 136 (92.5%) were cured with normal liver function and 9 (6.1%) improved with liver impairment. Two patients died, one of postoperative pneumonia and one of liver failure. We conclude that early radical surgery and careful postoperative follow-up are essential in the prevention of CBD complications such as cholangitis, pancreatitis, biliary stones, and development of carcinoma. This article is based on a special lecture delivered before the 19th meeting of the Japanese Society of Pancreatico-biliary Maljunction, on September 14, 1996, in Tokyo  相似文献   
999.
本文用中草药红背丝绸醇提物、乙酸乙脂提取物和单体CA-1201 三种不同成分对ET-1 在动物整体及离体水平生物学效应的拮抗作用进行了研究。结果发现:这三种成分对ET-1 致小鼠进行死亡有保护作用,使得小鼠的死亡率及死亡数下降;并可拮抗ET-1 致胸主动脉的缩血管效应,醇提物和乙酸乙脂提取物(10- 7母液)拮抗ET 缩血管效应分别为57.27% 和58.61% ;CA-1201 10- 8和10- 9 M 亦能拮抗ET-1 的缩血管效应;醇提物和乙酸乙脂提取物口服及CA-1201 静脉注射后能拮抗ET-1 的升压作用,拮抗ET-1 作用均呈现明显的剂量依赖性。提示中草药红背丝绸不同成分可拮抗ET-1 的生物学效应。  相似文献   
1000.
Background: We examined alternative methods of delivering cytokines as an adjunct for priming lymph node (LN) cells draining sites of vaccine inoculation for the purpose of generating immune cells for adoptive immunotherapy. Methods: Using syngeneic murine tumors we examined the ability of IL-2, IL-4, or GM-CSF delivered locally to a site of tumor inoculum to induce antitumor reactive draining LN cells. Mice were inoculated subcutaneously with tumor cells transduced to secrete cytokine; tumor cells admixed with fibroblasts transduced to secrete cytokine; or intralesional inoculation of cytokine in established tumor to induce sensitized LN cells capable of mediating tumor regression in adoptive transfer. Results: Both IL-4 and GM-CSF cytokines were effective in enhancing the antitumor reactivity of vaccine-primed LN cells compared to IL-2, which was ineffective. The local delivery of GM-CSF by autocrine or paracrine secretion of genetically engineered cells, as well as direct intratumoral delivery was capable of upregulating LN sensitization compared to systemic administration, which did not. Conclusions: The local delivery of GM-CSF as an adjuvant for tumor vaccination can be accomplished by various methods, including direct injection, which avoids the need for gene transfer.  相似文献   
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