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21.
目的:动态监测急性有机磷中毒动物在急性有机磷中毒及解救过程中血浆的乙酰胆碱酯酶活性和血糖值变化,依据此两项指标与中毒程度的相关性,为临床救治提供新的方法以及实验依据。方法:通过耳缘静脉注射5%敌百虫溶液(2mL/kg)先后对12只家兔建立急性有机磷中毒模型,分别在模型动物处于正常、轻、中、重度中毒和救治的时段采血,动态监测血浆乙酰胆碱酯酶活力和血糖两项指标变化。结果:在急性有机磷中毒过程中,血糖值升高与乙酰胆碱酯酶活力降低相比较,血糖浓度动态变化与中毒轻重程度相关性较好,并能体现机体对中毒的应激程度。结论:血糖浓度能较好地反映有机磷中毒深度以及机体应激程度,可作为临床评估危重程度的动态性快速诊断指标。  相似文献   
22.
目的探讨养血清脑颗粒对慢性脑供血不足患者血管内皮功能障碍和血栓前状态的干预效果。方法90例慢性脑供血不足患者按就时间顺序分为A组(对照组)、B组(养血清脑颗粒组)、C组(联合用药组)各30例,分别观察3组患者用药前和用药3个月后一氧化氮(NO)、血管内皮素-1(ET-1)、纤维蛋白原(FIB)、组织型纤溶酶原激活物抑制物(PAI-1)和组织型纤溶酶原激活物(t-PA)的变化,及内皮依赖性血管舒张功能(EDD)、非内皮依赖性血管舒张功能(NEDD)的变化,并进行对比分析。结果B组、C组经过治疗后,NO水平升高,ET-1水平和FIB减低,t-PA活性增强,PAI-1活性降低,EDD显著改善,两治疗组间相比差异无统计学意义;两治疗组治疗后分别与对照组相比差异具有统计学意义。结论服用养血清脑颗粒能够有效改善慢性脑供血不足患者的血管内皮依赖性舒张功能及血栓前状态,可以作为脑血栓形成的一级预防治疗。  相似文献   
23.
The receiver operating characteristic (ROC) method is a useful and popular tool for testing the efficiency of various diagnostic tests applicable to functional MRI (fMRI) data. Typically, the diagnostic tests are applied on simulated and pseudo-human fMRI data, and the area under the ROC curve is used as a measure of the efficiency of the diagnostic test. The effectiveness of such a method depends on how well the simulated data approximate the real data. For multivariate statistical methods, however, this technique is usually inadequate, as the spatial dependence among voxels is ignored for simulated data. In this work a modified ROC method using real fMRI data with a broader scope is proposed. This method can be applied to most fMRI postprocessing techniques, including multivariate analyses such as canonical correlation analysis (CCA). Also, the relationship of the modified ROC method with the conventional ROC method is discussed in detail.  相似文献   
24.
香菇多糖对肿瘤患者免疫状态的影响   总被引:6,自引:0,他引:6  
周振英  潘良喜 《江苏医药》1995,21(9):580-582
对78例恶性肿瘤患者的免疫状态及其对化疗和化疗加香菇多糖治疗反应进行了检测。结果表明恶性肿瘤患者免疫状态显著低于正常对照组。单纯化疗时,患者自然杀伤细胞(NK)和大颗粒淋巴细胞(LGL)比率明显下降;而化疗加香菇多糖治疗时,则能促进免疫功能活性细胞增加。  相似文献   
25.
Sry监测体外扩增造血细胞植入效果的实验研究   总被引:2,自引:0,他引:2  
目的:探讨Y染色体性别决定基因(Sry)作为评价和追踪造血细胞移植后植入状态检测指标的可行性。方法:根据Sry DNA序列设计引物及制备探针,然后进行PCR检测、斑点杂交和原位杂交.动态追踪经不同条件下体外扩增的纯系雄性小鼠BMMNC回输至雌性小鼠后的植入状态。结果:PCR结果显示在各移植组小鼠的骨髓有核细胞、脾细胞及外周血白细胞中均有Y染色体特异性序列的存在;斑点杂交结果显示在各回输组间并无明显差别,但用脾脏组织作原位杂交的结果则发现基质细胞支持扩增回输组的阳性颗粒数目与输注新鲜细胞组相似,但略少于雄性小鼠;而输注细胞因子扩增细胞实验组小鼠则明显少于雄性动物的阳性对照标本和基质细胞支持扩增回输组。结论:(1)经重复检测表明上述方法的重复性好,结果可信.可作为检测性别不同时造血干细胞移植效果的一种检测手段;(2)证实基质细胞支持下的体外扩增的造血细胞具有较好的植入能力。  相似文献   
26.
K.-W. Jauch 《Der Chirurg》1997,68(6):551-558
Summary. Trauma, operative interventions, infection and other disturbances of homeostasis lead to a uniform reaction of the body, namely release and activation of hormones and cytokines. Profound alterations of substrate flow result, with mobilization of energy stores and degradation of structural and functional proteins of vital organs like the gut mucosa. Due to these reactions the energy demands of the organs are met and energy-consuming synthesis of substrates is indicated. Clinically, hypermetabolism, hyperglycemia, lipolysis and increased urea production with negative nitrogen balance can be observed. The metabolic reactivity is reached by an increased substrate cycling. To avoid negative consequences such as organ dysfunction, a rational situation-adapted substrate supply is warranted as well as reduction of catabolic stimuli and stimulation of anabolic factors. The metabolic care of the surgical patient is still a basic and important task.   相似文献   
27.
采用静态蒸汽总压法实验装置,在29.94℃、39.92℃和49.93℃下,测定了1,1,1,2-四氟乙烷-1,1-二氟乙烷二元系汽液相平衡时的物料,总量、系统组成、蒸汽总压和汽相体积。结合物料衡算和T、P、x推算y的曲面样条函数法,计算出对应的平衡汽液相组成。用改进的PR状态方程和一个与温度无关的可调相互作用参数关联了实验数据。  相似文献   
28.
The purpose of this study was to evaluate whether the baseline stress-shortening data reflect the contractile state adequately and give results comparable to the evaluation of the end-systolic stress-shortening relationships using pharmacological manipulation of afterload. Five groups were studied (total 152 patients): a control group of 30 healthy volunteers, 32 patients after surgical correction of infantile tetralogy of Fallot, 50 patients treated for childhood malignancies with doxorubicin, 17 patients with left ventricular hypertrophy due to systemic hypertension, and 23 patients with congestive cardiomyopathy. In all patients except those with congestive cardiomyopathy, afterload was altered pharmacologically to evaluate the individual stress-shortening relationship. In all patients the baseline stress-shortening data were evaluated, as well as their relative positions to two predefined normal ranges for the relationship between end-systolic stress and shortening. Additionally, a slope value was calculated from the baseline data of the five groups studied and compared with the data obtained by pharmacological afterload increment. Our data show that the comparison of individual baseline data of end-systolic wall stress and fractional shortening with predefined normal ranges for the relationship between end-systolic stress and shortening is inadequate. The appropriate normal range to compare with is the 95% confidence interval of baseline stress-shortening data in normal subjects. Also the calculation of a slope value from the baseline stress-shortening data of a group of patients seems to be inappropriate. Such a slope value does not necessarily reflect the contractile state, as the specific conditions leading to variations of end-systolic wall stress are undefined and not standardized, and the correlation between baseline stress-shortening data depends largely on the influence of the end-systolic dimension on both parameters.  相似文献   
29.
Zinc(II) phthalocyanine is the active component of the liposomal formulation CGP 55847 which showed a high activity in photodynamic therapy in a variety of animal tumours. The photophysical properties of zinc(II) phthalocyanine have been studied in detail and compared to those of Photofrin, the only sensitizing agent approved so far for phase III/IV clinical trials. Since the efficacy of photodynamic therapy intrinsically depends on the spectroscopic features of the sensitizer, quantum chemical methods have proven to be an efficient means for optimizing chemical structures. As will be shown, a simple modification of the time-honoured INDO model of Pople allows a prediction of the singlet and triplet state properties of molecules of the size of zinc(II) phthalocyanine with an rms error of ≤ 1000 cm−1.  相似文献   
30.
The aim of the project was to survey the hospital prevalence of apallic syndrome in a federal state in Austria at an exact point in time. To achieve this, a point prevalence study was carried out on 28 November 2001 in the Vienna region. The central element was a questionnaire, which provided an exact recording of the patients' condition. An additional preliminary task was to check all the discharge diagnoses in the hospitals of the Vienna Hospital Association (Wiener Krankenanstalten Verbund) between 1996 and 2000 according to the ICD-9 diagnoses for apallic syndrome. These data should serve to cross-check the recorded results. All hospitals (n = 48) and nursing facilities (n = 44) in Vienna were included in this investigation. As the aim of the study was to record the prevalence of apallic syndrome in the population of Vienna, four patients of the group with full-stage apallic syndrome (n = 36) were excluded as they were from other federal states. In total, 32 hospital patients who met the clinical criteria for apallic syndrome (full-stage) were recorded. The point prevalence of apallic syndrome was 1.9/100,000 inhabitants. As a result of this study, the exact survey of hospital prevalence of apallic syndrome could be found. As a consequence, the Viennese government has developed a rehabilitation concept for patients with apallic syndrome in Vienna.  相似文献   
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