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121.
Immunoreactivity properties of serum dilutions andPlasmodium falciparum malaria antigens were measured and compared by ELISA technique using different ELISA plates to evaluate the role of antigens and serum dilutions for optimum binding. Also effort has been made to see the effect of reaction surface and material i.e. ELISA plates for binding capacity. Serological properties were estimated by ELISA methods for detection of malaria and determination of immunological characteristics. Three Pf antigens (PfAg) i.e. ring infected erythrocyte surface antigen: AR-1 (RESA), histidine-rich protein 2 antigen (HRP-2) and glycophospholipid antigen (grown and developed Pf antigen from PSJ-M strain): GPL1 have been used for serological testing of human blood samples by Enzyme Link Immunosorbant Assay (ELISA). 1∶100, 1∶1000 and 1∶10000 dilutions of Pf positive and negative serum (50 samples in each group) and 1∶1000 dilution of Pf antigens were used to measure immunoreactive properties by ELISA method. Result of PfAg-serum immunoreactivity study showed that GPL1 has the highest degree of immuno binding reactivity compared to other Pf antigens. HRP-2 and RESA antigens showed no significant difference to each other. Study also found that Costar and Fastec ELISA plates have a better Ag−Ab binding capability compared to immulon and Falcon plates at all dilutions of serum. Serum dilution of 1∶100 showed best binding and reactivity with Pf antigens followed by 1∶1000 and 1∶10000 showed lowest reactivity.  相似文献   
122.
Total cholesterol, total bilirubin, calcium, oxalate, inorganic phosphate, magnesium, iron, copper, sodium and potassium were analyzed quantitatively in gallstones, bile of gall bladder and sera of 200 patients of cholelithiasis (52 cholesterol, 76 mixed and 72 pigment stone patients) and their contents were correlated between calculi and bile and sera and bile in these three type of stone patients. A significant positive correlation was observed between total cholesterol, total bilirubin of calculi and bile, copper of bile and sera of cholesterol stone patients, copper of calculi and bile, total bilirubin, oxalate, magnesium, potassium of sera and bile of pigment stone patients and oxalate and iron of stone and bile, total bilirubin, oxalate, sodium of sera and bile of mixed stone patients. A significant negative correlation was found between magnesium of serum and bile of cholesterol stone patients, oxalate of calculi and bile of pigment stone patients and magnesium of serum and bile of mixed stone patients.  相似文献   
123.
Anupam Saxena 《Resonance》2011,16(3):220-237
Inspired by James Watt’s approximate straight line generator, kinematicians of the 19th century challenged themselves to design a mechanical device that could convert rotary motion into a perfect straight line and vice versa. Few inventions emerged in 1864 due to Peaucellier and Lipkin and in 1875 due to Hart. Just a year later, in 1876, Alfred B Kempe presented a generalized method for linkages that could exactly trace any algebraic curve of degree n and not just a straight line. This work of Kempe is of classical importance. Yet, many are not aware of it perhaps because the resulting linkages are quite complex. This article discusses Kempe’s method that highlights the way he treated the rotations analytically using only parallelograms and contra-parallelograms to get the final rigidbody linkage tracing a given algebraic curve. An elaborate example with geometric construction using only a ruler and compass is presented to help the readers understand the assembly of Kempe’s linkages.  相似文献   
124.
Effect of administration of 600 mg. vitamin E each day, for six days, was observed on activity of some of the anti-oxidant enzymes and levels of malondialdehyde (as an index of free radical mediated damage) in the platelets of patients reperfused after myocardial infarction. It has been found that vitamin E administration significantly lowers the level of malondialdehyde in the patients. Vitamin E administration increases the activities of anti oxidant enzymes (viz. superoxide dismutase, glutathione reductase and catalase) tested both in the patients and healthy controls. Vitamin E administration causes general stimulation of anti-oxidant enzyme activities both in healthy persons and the patients, however, lowering of lipid per-oxidation upon administration of vitamin E is specific for patients. These findings exhibit beneficial role of vitamin E administration in the management of the patients reperfused after myocardial infarction.  相似文献   
125.
An undergraduate student flow model: Australian higher education   总被引:3,自引:1,他引:2  
The probability of completing and the time to complete an undergraduate course are likely to vary by the age and sex of the student, and the field of study undertaken. In this paper a Markov chain is used to model the movement of undergraduates through the higher education system in Australia. Given the age of the student when they commence a course, this model provides estimates of the probability of them completing the course. It also provides estimates for the mean time a student takes to complete the course, and mean time they spend in the higher education system.  相似文献   
126.
This article attempts to showcase how one particularly financially endowed organization is seeking to modify its instructional and organizational practice to better serve its Iñupiat (Eskimo) target/client population. This is an extreme and instructive situation of socio‐cultural tension that provides interesting contrasts with the issues of performance in culturally diverse corporations, governmental and non‐governmental organizations. Considering the thematic argument made in this issue that multiple levels of analysis are sometimes required in developing human performance interventions in complex socio‐cultural contexts, this author observed that running a school system conceived almost entirely along Western lines while serving a predominantly non‐Western population leads to some problems at the macro, meso, and micro levels. This strongly suggests that, in today's cross‐ and multi‐cultural organizational contexts, human performance technology (HPT) analyses and interventions must unearth the rich complexity of issues embedded in our increasingly complex world or suffer the consequences of doing more harm than good.  相似文献   
127.
In this communication, we show the modulatory potential of papaverine, an opium alkaloid and a well known vasodilator agent on the ethanol-induced hepatic oxidative stress in male Wistar rats. Ethanol treatment (50% v/v) enhanced lipid peroxidation significantly accompanied by a decline in the activities of glutathione peroxidase (G-Px), glutathione reductase (GR) and depletion in levels of hepatic glutathione (GSH). Ethanol administration increased hepatic glutathione-s-transferases (GST). Enhanced lipid peroxidation induced by ethanol was significantly reduced when papverine was coadministered (P<0.05). In addition, the depleted levels of glutathione and inhibited activities of G-Px and GR recovered significantly (P<0.05) levelling off to control values on co-exposure. Papaverine (200 mg/kg bw) effectively antagonised the ethanol-induced lipid peroxidation and impaired glutathione levels and glutathione dependent enzyme systems. Our results suggest that papaverine is an effective chemopreventive agent in the liver and may suppress the ethanol-induced hepatotoxicity.  相似文献   
128.
A. K. Shukla  T. Prem Kumar 《Resonance》2010,15(12):1068-1073
Debye won the 1936 Nobel Prize in Chemistry for his contributions to molecular structure, dipole moment relationship and for diffraction of X-rays and electrons. Electrochemists, however, remember him for the Debye-Hückel limiting law that describes the behavior of strong electrolytes. In explaining the non-ideal behavior of strong electrolytes, his mathematical treatment assumes that each ion is surrounded by an ionic cloud of oppositely charged ions, which retards the movement of ions in the medium. The theory not only provides a method for calculation of activity coefficients, but has also helped, among other things, in our understanding of diffusion in ionic media, change in the rate of ionic reactions upon addition of salts, and biochemical reactions.  相似文献   
129.
Multiple myeloma is a disseminated malignancy of monoclonal plasma cells that accounts for 15 % of all hematological cancers. The present study was conducted to evaluate the role of inflammation and oxidant-antioxidant dynamics in the etiology of this disease. The study population comprised of 20 cases of multiple myeloma and 20 healthy controls. The parameters evaluated were serum malondialdehyde (MDA), superoxide dismutase (SOD) and ferritin levels. The serum MDA levels were 1.9 ± 0.96 nmol/ml in cases as compared to 0.98 ± 0.55 nmol/ml in the controls. Similarly, a statistically significant difference was noted in the SOD and ferritin levels between the cases and controls (93.2 ± 23.8 vs. 210.1 ± 190.5 U/ml and 285.8 ± 216.4 vs. 131.8 ± 30.1 ng/ml respectively). Our study highlights the imbalance in the oxidant-anti oxidant mechanism and the role of smoldering inflammation in the etiology of multiple myeloma.  相似文献   
130.
Quality in laboratory has huge impact on diagnosis and patient management as 80–90% of all diagnosis is made on the basis of laboratory tests. Monitoring of quality indicators covering the critical areas of pre-analytical, analytical and post-analytical phases like sample misidentification, sample rejection, random and systemic errors, critical value reporting and TATs have a significant impact on performance of laboratory. This study was conducted in diagnostic laboratories receiving approximately 42,562 samples for clinical chemistry, hematology and serology. The list of quality indicators was developed for the steps of total testing process for which errors are frequent and improvements are possible. The trend was observed for all the QI before and after sensitisation of the staff over the period of 12 months. Incomplete test requisition form received in the lab was the most poor quality indicator observed (7.89%), followed by sample rejection rate (4.91%). Most significant improvement was found in pre- and post-analytical phase after sensitisation of staff but did not have much impact on analytical phase. Use of quality indicators to assess and monitor the quality system of the clinical laboratory services is extremely valuable tool in keeping the total testing process under control in a systematic and transparent way.  相似文献   
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