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1.
目的 探讨肿瘤微血管密度(MVD)与肝细胞性肝癌临床病理及预后的关系。方法对30例肝细胞性肝癌根治性切除病理组织切片进行苏木精伊红染色.并用CD34单克隆抗体进行免疫组化染色,计数被CD34抗体染色的肿瘤血管内皮细胞数,以测定MVD。对MVD与临床病理因素及术后生存率关系进行分析。结果 单因素分析结果表明.MVD水平与肿瘤大小、TNM分期都是影响肝细胞性肝癌预后的因素;多因素分析结果表明.肝癌大小及肿瘤分期是肝细胞性肝癌独立预后因素。结论 MVD是肝细胞性肝癌一种预后因素。  相似文献   
2.
Rn-222 is the most important source of natural radiation and is responsible for approximately half of the received dose from all sources. Most of this dose is from inhalation of the Rn-222 progeny, especially in closed atmospheres. A Lucas cell technique, using a portable device, “PRASSI” (SILENA mod. 5S), for Rn-222 measurements inside the Centre for Radiation Protection and Radioecology (ZSR), Hannover University was used. The portable radon monitor PRASSI is suitable for radon gas continuous or grab sampling measurements with the scintillation cell technique. In recognition of the wide periodic variations in concentration, measurements were made daily for extended periods. At the same time, meteorological variables, such as temperature and humidity were observed so that their influence on radon levels could be evaluated. The radon average concentration during the year was about 55.9 Bq/m3 which gives rise to an annual effective dose 2.2 mSv y−1. The radon concentration is within the limits prescribed by the International Commission for Radiation Protection. A detailed analysis of radon distribution with seasonal variation is presented.  相似文献   
3.
目的了解典型办公场所内氡浓度水平随时间变化规律,为开展办公室内氡浓度水平调查或评价提供有效方案。方法选取典型办公室1间,用脉冲电离室测氡仪AlphaGUARD~开展9个月的连续测量,通过对测量数据的统计,分析办公室内氡浓度水平的变化规律。结果在9个月内,办公室内氡浓度的最大日均值、周均值、月均值以及季度均值与相应的最小值比分别为6.27、2.63、1.41和1.09;周末与工作日平均氡浓度的比值为1.17,工作日中上、下班时间段的平均氡浓度比值为0.86。结论办公场所内氡浓度水平虽然随时间变化,但3个月的连续测量均值基本可反映办公室内氡浓度的年度均值。  相似文献   
4.
The sequence is presented of RNA-5 of Echinochloa hoja blanca tenuivirus, a second tenuivirus associated with rice cultivation in Latin America (after rice hoja blanca virus). The RNA is 1334 nucleotides long and contains in the complementary sense RNA a single long open reading frame. The deduced amino acid sequence of this open reading frame shows that it encodes a highly basic and hydrophilic 44 kD protein (pc5) with about 50% similarity to the pc5 protein of maize stripe virus (MStV). This and other features of the RNA are discussed.The GenBank accession number of the sequence reported in this paper is L47430.  相似文献   
5.
The effect of different degrees of avitaminosis B6 in mice on the cytolytic activity of T lymphocytes, measured as the quantity of Na2Cr51O4 released from lysed target cells, was studied on a model of the primary immune response in a mixed lymphocyte culture in vitro. Keeping animals for 3 weeks on a diet without pyridoxine did not affect the ability of the lymphocytes to proliferate in vitro or their cytolytic activity. In animals receiving a diet without pyridoxine for 45 days the content of pyridoxal-5-phosphate in the spleen was 55% lower than in the control. Lymphocytes taken from these animals, when cultured in vitro, showed sharply weakened ability to incorporate [3H]thymidine into DNA in response to the alloantigen. The cytolytic activity of these lymphocytes also was reduced. The ability of different forms of pyridoxine to restore the functions of T lymphocytes, when disturbed by avitaminosis B6, was studied.Laboratory of Systemic Blood Diseases, Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Kraevskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 8, pp. 185–188, August, 1977.  相似文献   
6.
A reduction mammoplasty must produce a reduction in volume, a natural lasting shape, and minimal residual scarring. Many attempts to achieve this goal have been developed in recent years. The author described, in 1970, a vertical technique achieving an important reduction and a good shape but with the appearance of the end of the vertical scar below the brassiere line. In 1977, the author [3] modified the technique by the adjunction of a small horizontal scar to eliminate the inconvenience of the visible part of the vertical scar. In this article the author describes his technique which appears to be suitable for most types of breast deformities.  相似文献   
7.
传统卫生管理体制承袭了计划经济的所有特征,价格扭曲的宏观政策环境、资源的集中计划配置体制与公立医院在微观上的缺乏经营自主权三者并存.这种制度安排越来越不适应市场经济条件下卫生改革和发展的需要,而卫生经济体制改革始自微观经营机制,核心是两权分离和放权让利,这是自然的,同时也是正确的改革方向.  相似文献   
8.
Micro vascular free tissue transfer scores over the traditional myocutaneous flaps by providing better cosmesis and function. However, the increased operating tine and costs and the necessity for two operating teams sometimes, negate these advantages and even where this facility is freely available, myoentancous flaps continue to be widely used. To determine the ideal choice of reconstruction in patients after oral resection, we compared our experience with these two methods of reconstruction. Since 1997, when we first started micro vascular reconstruction, 17 patients have undergone this procedure for oral reconstruction. During this same period, 40 patients had pectoralis major myocutaneous flap reconstruction of the oral cavity. These two groups are compared with regard to cosmetic and functional results (as measured by patient’s level of satisfaction) operating time, duration of hospitalization, cost and complications. Results: Eightv seven percent of the patients in the micro vascular group and 75% in the myocutaneous group were satisfied with the cosmetic and functional results. In the microvascular group, average operating time was increased by 4 hours; hospitalization by 3 days and average cost of treatment was doubled. Flap failures and re-explorations were significantly higher in the micro vascular group. Based on these results, we would like to suggest the ideal method of reconstruction of the oral cavity in specific subgroups of patients in a corporate hospital setting.  相似文献   
9.
通过调节亲水性溶剂乙醇使用量,考察乙醇浓度的变化对乙醚-石油醚提取微胶囊中DHA的影响,并对提取条件进行优化,使乙醚有效地提取脂肪,提高了微胶囊中DHA提取率。本提取方法与国标法的酸水解法(GB5009.6-85)和哥特里-罗紫法(GB/T5009.46-1996)比较,DHA的提取率提高了10%以上,本提取方法的回收率为97.0%-98.3%,且具有操作简便、不易出现乳化等优点。  相似文献   
10.
超高压超临界微射流技术提取中药有效成分新方法   总被引:1,自引:0,他引:1  
阐述了超高压超临界微射流技术提取中药有效成分的方法及基本原理,对工艺流程进行了研究,优化了装置的结构,提高了提取效率。传统的方法不能有效提取中药有效成分,并且破坏了其中大部分热敏性物质,利用效率极低,应用超高压超临界微射流技术以中药牛蒡为例对其中的有效成分进行提取效果十分明显,具有常温提取有效成分,无因受热而产生的有效成分变性,提取得率高、提取液中的杂质少、提取时间短、节能等一系列优点,在纯度与提取率相同的条件下,提取时间由原来的至少1 h缩短为10 min。  相似文献   
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