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排序方式: 共有93条查询结果,搜索用时 31 毫秒
71.
稳定分布可以更好地描述实际应用中所遇到的具有显著脉冲特性的随机信号和噪声。与其它统计模型不同,α稳定分布没有统一闭式的概率密度函数,其二阶及二阶以上统计量均不存在。针对系统中存在独立SαS噪声与高斯噪声,本文提出了一种稳定分布环境下的非线性自适应最小p范数迭代算法。计算机模拟和分析表明,这种算法是一种在SαSG分布背景噪声条件下具有良好韧性的滤波方法。 相似文献
72.
A serial follow up study of cardiac marker enzymes during the week after acute myocardial infarction
Laboratory infarction diagnostics are based on the detection of elevated serum activities of creatine kinase (CK) Creatine
kinase Isoenzyme MB (CKMB) and Transaminases. Determination of these cardiac marker enzymes permits the diagnosis of transmural
myocardial infarction. However in such patients the diagnosis of acute myocardial infarction can be confirmed by the clinical
symptoms and changes in the ECG, in addition to the enzyme assays. The 50 AMI patients selected in the present study were
those admitted to the ICCU of Shri Krishna Hospital, Karamsad. The blood samples were taken at Zero hours (i.e. at the time
of admission of the patient). Within 6 hrs of the starting of chest pain, 1.5 million units of streptokinase were mixed with
100 to 150ml of normal saline and administered by infusion over a period of one hour. The blood samples were further collected
at intervals of 6 hrs, 14hrs, 32hrs, 48hrs, 5th day and 7th day. The blood samples were analyzed for CK, CKMB, SGOT, α HBDH and Cardiac specific Troponin T. By 6hrs the CK and CKMB
values had started rising, the rise continuing at 14hrs with peak values at 32hrs. The CK showed a slight decrease by 48 hrs.
The cardiac Troponin T showed wide time window from 4 hrs to 7th day for detecting myocardial damage. The maximum cardiac Troponin T values were during the first 24hrs. Cardiac Troponin
T in serum appears to be a more sensitive and early indicator of myocardial cell injury in comparison to CKMB. 相似文献
73.
Objective To investigate the protective effect of nicorandil and amlodipine in isoproterenol induced myocardial necrosis in rats.
Methods The effect of nicorandil and amlodipine on bio-chemical parameters during isoproterenol induced myocardial necrosis in rats
was examined by determining the activity of creatine phosphokinase (CK), lactate dehydrogenase (LDH), and transaminases (AST,
ALT) in the serum of the animals.
Results Isoproterenol (150mg/kg/day) administered rats showed statistically significant rise in activities of LDH(1.02±0.19 to 1.85±0.05),
CK(4.3±0.19 to 7.37±.27), AST(0.38±.03 to 0.78±.05) and ALT(0.19±.017 to 0.346±.027) in the serum. Pre-co-treatment of rats
with nicorandil and amlodipine significantly lowered the raised levels of these enzymes and thereby restoring the enzyme activity
to near normal as was clear from the chart i.e. LDH was 1.10±0.04, CK was 4.37±0.19, AST and ALT were 0.39±0.028 and 0.199±0.04
respectively.
Conclusion It is demonstrated that pre-co-treatment with nicorandil and amlodipine either alone or in combination help in providing protective
effect on isoproterenol induced myocardial necrosis. 相似文献
74.
Glucose-6-phosphate dehydrogenase (G6PD), a cytoplasmic enzyme, plays a protective role during oxidative stress in eucaryotic
cells, since they provide coenzymes and substrates to the primary antioxidant enzymes. The redistribution of G6PD in the hippocampus
was studied post-ischemia (PI). There was a characteristic localisation of G6PD in pyramidal cell layers of the rat hippocampus.
In hippocampus CA1 cells were stained weakly whereas CA3 cells showed strong histochemical staining. Ischemia induced up-regulation
of G6PD in the hippocampus was in a specific manner. First, the activity increased in the whole hippocampus (at 4 hours PI)
which persisted 6 hrs PI in CA1 area. However G6PD activity decreased in the CA3 area & dentate gyrus. At 10 & 24 hrs PI,
activity decreased in CA1 area but normalised in CA3 area & dentate gyrus compared to controls. This suggests that the sensitive
CA1 neurons are transiently capable of generating an anti-oxidative arsenal to cope with the oxidative stress in the first
few hours PI. We can conclude that the brain contains inducible endogenous mechanisms that are capable of enhancing the ability
of neurons to withstand lethal ischemic challenge.
(Presently working in Vardhman Mahavir Medical College & Safdarjung Hospital, New Delhi) 相似文献
75.
郭英杰 《吉林体育学院学报》2008,24(4):83-85
丙酮酸脱氢酶(pyruvate dehydrogenase complex,PDHc)是机体有氧代谢过程中起主要调控作用的酶系之一。了解PDHc的组成和特性、运动对PDHc活性及主要调控因素的影响的最新研究情况,对解决运动医学和运动生物化学中的一些难点和热点问题具有十分重要的意义。 相似文献
76.
77.
研究了氟化铝法除去铝矾土中的SiO_2、TiO_2、Fe_2O_3等杂质以制得含量为97%的α—Al_2O_3产品.并确定了最佳的除杂工艺条件. 相似文献
78.
Singh TD Barbhuiya MA Gupta S Shrivastav BR Jalaj V Agarwal N Tiwari PK 《Indian journal of clinical biochemistry : IJCB》2011,26(2):146-153
We have studied the expression of lactate dehydrogenase and its isoforms in gall bladder cancer, cholelithiasis and chronic
cholecystitis. Quantitative and qualitative assays of lactate dehydrogenase and its various isoforms were carried out in the
blood sera of patients and healthy controls along with parallel estimation of various liver function test enzymes. Statistical
analysis was done using the software Graph Pad Prism. Significantly high expression of lactate dehydrogenase along with alkaline
phosphatase and total bilirubin (P ≤ 0.05) was observed in all the three clinical conditions as compared to controls. LDH showed an increasing trend from stage
I to stage IV of GBC indicating a significant positive association with the disease progression. The levels of LDH 3 and 4
isoforms appeared significantly more elevated in GBC than cholelithiasis or chronic cholecystitis. We suggest that a careful
estimation of total LDH and its isoforms 3 and 4 alone or along with alkaline phosphatase and total bilirubin during different
clinical stages, like chronic cholecystitis, cholelithiasis and GBC, may prove to be a potentially useful biomarker in the
prognostic management of gall bladder diseases, specifically GBC. 相似文献
79.
80.
Sandhya Mishra D. C. Sharma Praveen Sharma 《Indian journal of clinical biochemistry : IJCB》2004,19(1):71-75
The study includes 102 confirmed cases of carcinoma breast with and without metastasis and 25 healthy non-pregnant females.
They were evaluated for blood levels of Ferritin, GSH, LDH, ALP, GGT and Hb before and 21 days after mastectomy. A significant
increase (p<0.001) was observed in ferritin, LDH and GSH levels in cancer patients without metastasis in comparison to normal
control subjects. Patients with metastasis had further elevated (p<0.001) levels of Ferritin, ALP and GGT as compared to non-metastatic
patients. Mastectomy in both the cases i.e. with and without metastasis resulted in non-significant decrease in all the biochemical
parameters suggesting that longer follow up could confirm post surgery decrease in the biochemical parameters. The results
of the study suggest cost effective, usefulness of Ferritin, ALP, GGT and GSH/Hb ratio in differentiating breast cancer patients
with and without metastasis which can be assayed in smaller laboratories. 相似文献