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3,5-diBr-PADAP直接光度法测定血清锌   总被引:2,自引:0,他引:2  
目的 建立一种不去除血清蛋白、简便灵敏的直接光度法测定血清锌。方法 以新的有机试剂2 -(3 ,5 二溴 -2 -吡啶偶氮 ) -5 -二乙氨基酚 (3 ,5 diBr -PADAP)为显色剂 ,在有表面活性剂存在的Tris-HC1介质中 ,手工分析法和自动分析法测定血清锌。结果 该法线性范围 0~ 80 μmol/L ,手工分析法和自动分析法平均回收率为 99 9%和 10 0 2 % ,批内变异系数 (CV)和批间变异系数分别为 0 0 18、 0 0 17和 0 0 2 8、0 0 2 6,与原子吸收分光光度法比较具有良好的相关性 ,线性回归方程和相关系数分别为Y =1 0 0 4X -0 12 6,r=0 9912和Y =1 0 0 6X -0 195 ,r =0 0 992 8。 89例健康人血清锌含量分别为 8 96~ 2 2 5 2 μmol/L和 8 63~2 2 43 μmol/L (x± 2s)。结论 用 3 ,5 diBr-PADAP直接光度法测定血清锌方法简便、灵敏可靠 ,适合临床应用。  相似文献   
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A direct solution is proposed to an optimal control problem of linear econometric systems with a quadratic welfare loss function when there are linear equality constraints on the control variables. The direct solution proposed here eliminates the problem of non-uniqueness of the optimal solution, which is present when this optimal control problem is solved using the recursive algorithm proposed by Chow,1 Pindyck2 and Tan.3 If a unique solution to the optimal control problem exists, then the direct solution and the recursive solution coincide.  相似文献   
4.
Abstract A young male motorcyclist presented to the Pelvic Unit with an open-book fracture of his pelvis and an acute obstructed direct inguinal hernia. He was managed operatively and made an excellent recovery. Traumatic abdominal wall hernias are rare. This is a unique combination of injuries that the trauma surgeon should be aware of.  相似文献   
5.
课题研究提供了改良的人精子染色体直接制备,G显带核分析技术。在对80例对象的人精子染色体直接制备,G显带核型分析中,成功率为62.5%,较Templado方法的成功率(58.1%)进一步提高。通过对正常人,不育,流产对象的男性精子染色体研究,发现精子染色体数目和结构畸变率分别为:正常人2.3%和0%,不育14.0%和4.8%,流产组4.5%和2.4%,不育和流产组的畸变率较正常人增加。在对5例染色  相似文献   
6.
Combined direct injection venography (DIV) and equilibrium angiography (EA) were performed in 13 patients, by injecting in vitro labeled 99mTc autologous RBC, via pedal veins, and imaging the first pass and the equilibrium phase. This paired comparative study of DIV with EA shows that DIV has advantages over EA because it provides selective information on the deep venous system from the calves to the inferior vena cava. DIV provides information on the flow dynamics and the high contrast first pass images provide better definition of non filling venous segments as well as visualization of collaterals. When using 99mTc-MAA, lung perfusion can also be imaged. DIV is recommended as the procedure of choice for the diagnosis of DVT and EA should be employed only when pedal vein injection is not possible.  相似文献   
7.
Dendritic cells (DCs) are potent antigen presenting cells and possess a direct anti-tumor cytotoxic ability. Nevertheless, the mechanism of anti-tumor cytotoxicity by DCs and the methods for its evaluation are not fully elucidated. In order to clarify this mechanism of cytotoxicity, we examined the ability of DCs 1) to suppress [3H] thymidine (3H-TdR) uptake by tumor cells; 2) to induce cytolysis on 51Cr-labeled tumor cells; 3) and to induce DNA fragmentation on 3H-TdR labeled tumor cells (JAM test). Cytolysis and DNA fragmentation are markers of necrotic and apoptotic mechanisms of cytotoxicity in vitro, respectively. DCs inhibited approximately 38.6% to 54.8% of the growth of B4D6, NB4, U937, and Daudi cells as evaluated by the uptake of 3H-TdR. However no cytolysis was verified by 51Cr-release assay. On the other hand, cytotoxicity rates found using the JAM test ranged from 3 to 81% depending on the cell line and the effector to target cell ratio. The discrepancy of cytotoxicity between 51Cr-release assay and the JAM test may be due to the phagocytosis of apoptotic tumor cells or the absorption of released 51Cr by DCs surrounding the target cells. In conclusion, the JAM test was more sensitive than the 4-h and the 10-h 51Cr-release assay to investigate cytotoxicity mediated by DCs toward hematopoietic tumor cell lines in vitro.  相似文献   
8.
A Direct Comparison of the Skin Conductance and Skin Resistance Methods   总被引:1,自引:0,他引:1  
The purpose of the present study was a direct comparison between simultaneous recordings of skin conductance and skin resistance. Sixty male students received a series of 30 white noise stimuli, while measures were taken continuously from four sites on the palmar surfaces of the fingers. Evaluations were made for response amplitudes, recovery, and for an approximate area measure. Magnitude of reactions and reliabilities were compared using ANOVA procedures. Behavioral concordances were estimated as correlations with the subjects' ratings of stimulus intensities. Conductance and resistance measures do not differ in amplitude, in area, or in strength of their reliabilities and behavioral concordances. No differences in any respect are found between sites. Skin conductance yields significantly (p < .01) shorter recovery times than skin resistance, which is discussed in terms of membrane permeability change.  相似文献   
9.
In response to the spiraling anger and frustration voiced by the emergency room (ER) medical staff and the observed negative interactions between the alcohol-dependent patient and the ER staff, the author completed a 6-month retrospective review of all patients evaluated by the ER service with a complaint of alcohol abuse, chronic alcoholism, or requesting detoxification. As a result of that study, an ER-based comprehensive approach to the management of this population was proposed. Utilizing an existing Connecticut state statute, a specific approach to manage the skid-row alcoholic arriving repeatedly in the ER was developed. I report on this ER-based model and an approach to "capturing" the skid-row alcoholic.  相似文献   
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