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Biomedical subjects

S P Mishra

Publications and source records attributed to S P Mishra.

16 recordsLinked to original sources
PubMed2005

EPR investigations on radiation induced chemical transformations in Pd(ClO4)2/i-PrOH/HClO4 system from 77 to 300 K.

The EPR studies have been carried out on gamma irradiated samples of Pd(ClO4)2 in 9 M/4M HClO4 in the presence and absence of isopropanol [i-PrOH (5%, v/v)], in the temperature range of 77-300 K. The EPR studies revealed the formation of Pd+ complex, Pd3+ complex and several radicals such as H., OH., ClO3., ClO4. and O3- on radiolysis of these systems. Reduction of Pd2+ to Pd clusters could not be observed in the absence of i-PrOH and warming of the irradiated sample finally resulted in recovery of Pd2+ complex. However, in the presence of 5% i-PrOH, strongly oxidizing radicals like OH., ClO3. and ClO4. are suppressed and (CH3)2C.OH radical was produced along with reducing species like H.. EPR spectra in these strongly reducing conditions showed formation of Pd+ complex, which on heating above 230 K, disproportionated into Pd0 and Pd2+ complex and finally lead to formation of Pd metal aggregates. Simultaneously, pulse radiolysis technique has been employed as an alternative method to verify the EPR observations.

Electron Spin Resonance Spectroscopy↗
PubMed2004

Use of oxide minerals to abate fluoride from water.

The removal of fluoride from aqueous solutions has been investigated using various oxide ores such as refractory grade bauxite, feed bauxite, manganese ore, and hydrated oxides of manganese ores (WAD). The refractory grade bauxite showed promising results. The studies were carried out as functions of contact time, pH, concentration of adsorbents, concentration of adsorbate, and temperature. The adsorption was rapid during the initial 5 min but equilibrium was attained within 120 min. The adsorption followed first-order kinetics. The present system followed the Langmuir adsorption isotherm model. Various thermodynamic parameters such as free energy, enthalpy, entropy, and equilibrium constants were calculated. The isosteric heat calculations showed that the adsorption process followed a heterogeneous model.

Journal Article↗
PubMed1999

Ion exchangers in radioactive waste management. Part XI. Removal of barium and strontium ions from aqueous solutions by hydrous ferric oxide.

The uptake of Ba(II) and Sr(II) by hydrous ferric oxide (HFO) was studied as a function of contact time, concentration, temperature and pH of the respective adsorptive solutions employing the 'radiotracer technique'. The uptake of both the ions was found to increase with the increase in concentration, temperature and pH of the adsorptive solutions. Concentration dependence data fitted well to the Freundlich adsorption isotherm over the entire range of concentration (10(-2)-10(-7) M) and the uptake process followed first-order rate kinetics. The desorption experiments demonstrate the irreversible nature of the uptake process, however, in the presence of H+ ions, i.e. on acidification, an appreciable amount of metal ions were removed in the bulk solution. The radiation stability of hydrous ferric oxide towards the uptake of Ba(II) and Sr(II) was also examined by using samples of hydrous ferric oxide irradiated by neutrons and gamma-rays prior to be employing as sorbents. The presence of some mono- and divalent co-ions along with the studied ions suppressed their removal appreciably.

Adsorption↗
PubMed1997

The uptake behaviour of rice (Jaya) husk in the removal of Zn(II) ions--a radiotracer study.

Sequestering of Zn(II) ions at the surface of rice husk has been studied as a function of contact time, adsorptive concentration, temperature and pH, using the radiotracer technique employing a 65Zn radiotracer. A relatively slow uptake of metal ion increasing with bulk dilution (10(-2) to 10(-7) mol/dm3) was seen, which obeys the first-order rate law and agrees well with the classical Freundlich adsorption isotherm. The removal of metal ions from the bulk increases with the increase in pH (3.2-10.2) and temperature (293-323K) and evaluation of the thermodynamic data shows that the process involved is endothermic and apparently irreversible in nature, suggesting an ion exchange mechanism along with surface complexation. On the other hand Cd(II) was not adsorbed on the surface of the rice husk at pH 6.2.

Adsorption↗
PubMed1994

Necrotizing enteritis simulating Pig-Bel disease in northern India.

OBJECTIVE: A clinicopathological study of patients presenting with necrotizing enteritis, similar to the Pig-Bel disease of Papua New Guinea. METHODS: A clinicopathological study of 95 patients presenting in last ten years with acute abdominal pain with diarrhea and/or bleeding per rectum and vomiting and found to have lesions similar to Pig-Bel disease. RESULTS: 89% of the patients were young adult vegetarians from lower socio-economic strata. 94% of cases presented between May and August every year showing a marked seasonal variation. Jejunum was the most common site (95%) involved. Gross examination showed blackish brown 'skip' lesions with gangrene and perforations. Histology showed marked necrosis and congestion of all the layers with mucosal ulcerations. CONCLUSION: A disease simulating Pig-Bel disease occurs in India. It is more common in young adult vegetarians and may have a different etiology from that proposed in endemic regions.

Adolescent↗
PubMed1988

Bumetanide, spironolactone and a combination of the two, in the treatment of ascites due to liver disease. A prospective, controlled, randomized trial.

There are few studies available comparing the efficacy of loop and distal diuretics and a combination of the two groups, in the treatment of ascites due to liver disease. Thirty-seven nonazotemic cirrhotic patients with ascites were randomly allocated to receive for 2 weeks bumetanide (group A, n = 13), spironolactone (group B, n = 12) or a combination of the two drugs (group C, n = 12) after a 5-day stabilization period. The response to the treatment was 69, 42 and 83% in groups A, B and C, respectively; the difference was not significant. Hypokalemia was seen in 4 patients of group A and mild hyperkalemia in 2 patients of group B. Electrolyte disturbances were minimal in patients of group C. The response to diuretic treatment was prompt in groups A and C. It can be concluded that a combination of loop and distal diuretics is superior to a one-drug regimen in achieving a rapid and better diuretic response with fewer side effects.

Administration, Oral↗
PubMed1988

Construct validity of neuropsychological instrumentation with a learning disabled population.

The construct validity of the Reitan-Indiana Neuropsychological Test Battery (R-INB)for Children with a learning disabled population was examined. Forty-two subjects classified as learning disabled also were administered the Wechsler Intelligence Scale for Children-Revised (WISC-R) and Wide Range Achievement Test (WRAT) subtests. Factor analysis of the data revealed four factors: verbal intelligence, psychomotor speed, achievement, and memory. Evidence from this study indicates that the overall construct paradigm as conceptualized by the author of the R-INB does not exist. Implications of these findings are discussed.

Journal Article↗
PubMed1988

Ethanolamine oleate versus absolute alcohol as a variceal sclerosant: a prospective, randomized, controlled trial.

Forty-seven patients with esophageal variceal bleeding were randomly allocated to undergo sclerotherapy on a 3 weekly schedule with either 5% ethanolamine oleate (23 patients) or absolute alcohol (24 patients), in an attempt to compare the efficacy and safety of the two sclerosants. Sclerotherapy with absolute alcohol eradicated esophageal varices significantly earlier compared with ethanolamine oleate (12.9 +/- 5.2 vs 22.3 +/- 8.2 wk, respectively, p less than 0.001). The mean number of injection courses and the mean amount of sclerosant required for variceal obliteration was also significantly (p less than 0.001) less in the alcohol-injected group. Although the total number of rebleeding episodes were significantly (p less than 0.05) less in the alcohol-injected group, the frequency of rebleeding was not significantly different between the two groups (20.8% vs 30.4%, respectively, p greater than 0.05). Two (8.1%) patients died due to rebleeding in the ethanolamine-injected group, whereas in the alcohol group, none died. There was no significant difference in the frequency of complications with the two sclerosants. Besides the relative ease of rapid injection due to its aqueous nature, alcohol is readily available and relatively economical (total cost of sclerosant per patient; alcohol US $0.50, ethanolamine US $60). In conclusion, absolute alcohol appears to be a useful alternative to 5% ethanolamine oleate as a variceal sclerosant.

Adult↗
PubMed1984

Recategorized WISC-R scores of learning-disabled children from Mexican-American culture.

Examined the generalizability of the Bannatyne WISC-R profile of learning-disabled children to a sample of children from Mexican-American culture. A sample of 64 Mexican-Americans diagnosed as learning disabled were used in the study. Recategorized scores were subjected to 1 X 3 repeated measures ANOVAs and the differences between mean categorized scores were analyzed by Newman-Keuls tests for simple effects. Analysis of the obtained data suggested that learning-disabled Mexican-American children were not characterized by Spatial greater than Conceptual greater than Sequential patterns as predicted by Bannatyne. The WISC-R performance of these children was found to be similar on Sequential and Conceptual categories. In spite of the lack of generalizability of the Bannatyne profile to the Mexican-American group, some interesting similarities and differences in performance patterns of the two groups of Ss were observed.

Child↗
PubMed1984

WISC-R performance patterns of learning-disabled children from Papago culture.

Examined the WISC-R profiles of learning-disabled children from the Papago culture. A sample of 46 Papagos diagnosed as learning disabled were used in the study. Recategorized scores were subjected to 1 X 3 repeated measures ANOVA, and the differences between mean categorized scores were analyzed by Newman-Keuls tests for simple effects. Analysis of the obtained data suggested that learning-disabled Papago children were not characterized by Spatial greater than Conceptual greater than Sequential pattern because WISC-R performance of these children was found to be similar on Sequential and Spatial categories. Caution in the use of WISC-R profile for differential diagnosis was recommended.

Arizona↗
PubMed1983

The comparability of WAIS and WAIS-R IQs and subtest scores.

Examined the comparability of the WAIS and WAIS-R by administering the two scales to a sample of 88 adults in a counterbalanced order. The obtained data were analyzed by correlational and repeated measure three-way analysis of variance procedure. The indices of obtained correlation coefficients suggested a high degree of similarity between the two scales. The findings from ANOVA indicated statistically significant differences in the subtest performance (except in the performance of the Picture Arrangement), and three IQs on the WAIS and WAIS-R. Performance of Ss was found to be higher on the WAIS as compared to their performance on corresponding subtests and IQs on the WAIS-R. These results were found to be consistent with the data reported by earlier studies that compared revisions of the Wechsler and Stanford-Binet scales with older tests.

Adult↗
PubMed1982

Intelligence test performance as affected by anxiety and test administration procedures.

Compared the scores obtained by high and low anxious Ss, when the Wechsler Adult Intelligence Scale was administered by a trained examiner, with those obtained when the test was administered mechanically. A sample of 40 Ss were classified into high and low anxious groups in terms of their scores on the Taylor Manifest Anxiety Scale. Each S was given half the items of the WAIS verbal scale by a trained examiner and half by machine. Analysis of the scores under these two modes of test presentation, using a 2 X 2 X 2 factional analysis of variance, showed no significant differences in performance of high and low anxious Ss under two testing situations. Similarly, there were no differences in the performance of male and female Ss. However, the Ss showed a significant tendency to score higher when the test was given by an examiner than when the test was administered mechanically. Such differences, however, were not observed when the scores on each subtest were compared under two testing conditions except in the case of the Information and Arithmetic subtests.

Adult↗