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61.
In some sense, bioethics was built on conflicts. Abortion, physician-assisted suicide, patients’ demand for autonomy all are staple and contentious issues. And the controversies continue to proliferate. What forum best serves such debates? A look at political theories of democracy can help answer that question. The most promising for bioethics debates are theories that ask citizens and officials to justify any demands for collective action by giving reasons that can be accepted by those who are bound by the action. This conception has come to be known as deliberative democracy. 相似文献
62.
nm23基因在前列腺癌中的表达与癌转移的关系 总被引:4,自引:0,他引:4
应用LSAB免疫组织化学染色方法,研究转移抑制基因nm23表达产物二磷酸核苷激酶(NDPK)在前列腺癌中的表达及其意义。结果表明,NDPK/nm23在前列腺癌中有较高的表达,阳性率为500%(20/40)。无前列腺癌转移者其阳性率为667%(12/18),有前列腺癌转移者其阳性率为364%(8/22),两者比较差异有显著性(P<005),并与前列腺癌分化程度和临床分期有显著相关。因此,nm23基因可能在前列腺癌形成及转移过程中起不同的调节作用,其表达程度与前列腺癌转移呈负相关,有可能成为评价前列腺癌病人预后的一项新指标。 相似文献
63.
采用SD大鼠慢性肾血管性高血压模型,气-液色谱法测定高血压组(n=8)、对照组(n=9)脑细胞膜游离脂肪酸(Free Fatty Acid,FFA)单组分水平。结果显示高血压组脑细胞膜FFA组份中C20:4、C22:6水平显著高于对照组(PO.05)。提示继发性高血压大鼠存在脑细胞膜FFA代谢障碍。 相似文献
64.
分次使用国产ELISA药盒测定血清(浆)Lp(α)浓度过程中,进行质控、标本贮存等实验,并建立Lp(α)浓度水平的正常参考值。结果:①血清Lp(α)测值平均组内变异5.18%、组间9.86%,实验室间标准质控变异率0.18%;②标本存放于—25℃310天或者冻融3次后Lp(α)测值均无明显改变;③Lp(α)的血清与血浆值之间高度相关(r=0.974,P<0.001,n=60);④血清Lp(α)浓度在本室的正常参考值为204.3±126.4mg/L,并且呈正偏态分布,经对数或平方根变量交换均可使其正态化。 相似文献
65.
David L. Mattson Shanhong Lu Allen W Cowley Jr 《Clinical and experimental pharmacology & physiology》1997,24(8):587-590
1. Nitric oxide (NO) has been implicated as an important controller in the short- and long-term regulation of arterial pressure. Studies performed in our laboratory have demonstrated that chronic intravenous administration of the NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) selectively decreases renal medullary blood flow, causes sodium and water retention and leads to hypertension. 2. To determine the importance of the renal medullary effects in this model of hypertension, further studies were conducted to examine the influence of selective stimulation or inhibition of renal medullary NO on whole kidney function and cardiovascular homeostasis. With the use of a unique catheter to directly infuse into the renal medullary interstitial space, stimulation (bradykinin or acetylcholine) or inhibition (L-NAME) of renal medullary NO selectively increased or decreased renal medullary blood flow. 3. The changes in medullary flow in these experiments were associated with parallel changes in sodium and water excretion independent of alterations in renal cortical blood flow or glomerular filtration rate. 4. Studies were then undertaken to examine the long-term effects of selective NO inhibition in the renal medulla on cardiovascular homeostasis. Chronic infusion of L-NAME directly into the renal medullary interstitial space of uninephrectomized Sprague-Dawley rats led to a selective decrease in renal medullary blood flow that was sustained throughout the 5 day L-NAME infusion period. The decrease in medullary blood flow was associated with retention of sodium and the development of hypertension and the effects were reversible. 5. The data reviewed indicate that NO in the renal medulla has a powerful influence on fluid and electrolyte homeostasis and the control of blood pressure. 相似文献
66.
CT造影剂碘海醇注射液的制备及动物实验 总被引:3,自引:0,他引:3
本文报道了非离子型X-CT造影剂碘海醇注射液的制备及动物实验结果。磺海醇的最大吸收波长λ_(max)为244nm。讨论了温度、浓度对磺海醇溶液粘度的影响:粘度随温度的升高而下降,呈负线型相关;粘度随浓度(C)升高而激剧升高,与浓度的四次方呈线性相关:V_(37℃)=472.589[C] ̄4+1.121(r=0.9977)V_(30℃)=663.813[C] ̄4+1.152(r=0.9996)V_(20℃)=1082.953[C] ̄4+1.433(r=0.9982)使用该注射液进行狗的造影实验,获得了清晰的造影图像。 相似文献
67.
68.
系统地介绍了军队卫生系统计算机应用的概况,总结了军队卫生系统自动化建设的主要经验,并提出了加强军队卫生系统计算机应用的设想。 相似文献
69.
本文对14岁以下健康小儿171名,成人30名及初生儿脐带血30份进行了血清叶酸和维生素B_(12)含量测定,171名小儿于采血前均经补足叶酸和维生素B_(12)。结果:血清叶酸(nmol/L)的正常值低限,<4岁者为6.1,4~14岁为8.4,成人为5.0;血清维生素B_(12)(pmol/L)的正常值低限,<1岁为459,1岁~成人为107。 相似文献
70.
Amy J Bastian Valerie E Kelly Fredy J Revilla Joel S Perlmutter Jonathan W Mink 《Movement disorders》2003,18(9):1000-1007
The purpose of this study was to determine the effects of unilateral versus bilateral subthalamic nucleus (STN) stimulation on quantitative measures of walking and reaching in Parkinson's disease (PD). We used kinematic measures and the Unified Parkinson's Disease Rating Scale (UPDRS) motor subscale (subscale III) to evaluate the movement of 6 people with PD who had bilateral STN stimulators implanted for at least 6 months and withheld their anti-parkinson medication for at least 8 hours. Subjects were studied with both stimulators off, one on, and both on. Kinematic data were collected as subjects walked, reached to a target, and were rated using the UPDRS motor subscale. STN stimulation improved walking speed and stride length, with the greatest benefit from bilateral stimulation. Reaching speed was improved by unilateral STN stimulation alone, with no additive effect of bilateral stimulation. UPDRS motor subscale ratings paralleled the kinematic findings. STN stimulation did not restore PD subjects' movements to the level of age-matched controls. Overall, these results provide further evidence that the basal ganglia pathways involved in control of walking and reaching may be distinct. We speculate that basal ganglia may influence walking through bilateral pedunculopontine projections and reaching through ipsilateral thalamocortical projections. Our findings also suggest that maximal improvement of walking requires bilateral rather than unilateral STN stimulation. 相似文献