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91.
The present work was undertaken to study the changes in osmotic resistance of stored blood, used for blood transfusion. Blood samples of 50 cases from Orissa Red Cross Blood Bank, Cuttack, were studied. The blood was collected in acid citrate dextrose solution and stored at 4 degrees C. Storage was done under usual condition followed in blood banks. Osmotic fragility was determined at 3 days interval up to 15 days. In each case ESR was determined and in 20 cases plasma fibrinogen level was determined. In this study there was gradual increase in fragility which was maximum on 9th day and then slowly declined, which was statistically significant. ESR decreased markedly after 6th day, which was also statistically significant. 相似文献
92.
Chaman L. Nanda John H. Ternouth Alex C. Kondos 《Journal of the science of food and agriculture》1977,28(1):20-22
A method was tested for measuring in vitro papain proteolysis of extracted plant protein to products soluble in trichloroacetic acid. The effects of incubation time, temperature and enzyme concentration were examined. Maximum proteolysis (82.9%) was obtained at 70°C for 24 h and a ratio of papain/protein substrate of approximately 1:10. 相似文献
93.
This paper presents algorithms for designing assembly lines with overlapping work stations where technological limitations may restrict simultaneous performance of certain work elements on the same copy of a product. Computational procedures for the handling of these physical constraints are developed, utilizing techniques from disjunctive graph theory and illustrated with sample problems. 相似文献
94.
95.
P. J. Boon 《河流研究与利用》1988,2(3):389-409
The impact of river regulation on invertebrates has received comparatively little attention in the U.K., with most studies concentrating on the effects of impoundment. During dam construction invertebrate diversity and abundance decreases. Longer term alterations in community structure (which usually extend for a relatively short distance downstream) reflect changes in flow, substrate, temperature, and water quality. In particular adverse effects on invertebrates have been attributed to a reduction in substrate heterogeneity together with an accumulation of sediment. Responses to impoundment within and between taxonomic groups are highly variable. In general Ephemeroptera and Coleoptera are reduced. Of the Plecoptera the Perlodidae and Chloroperlidae are more likely to be adversely affected than the Nemouridae or Leuctridae. The impact of impoundment on net-spinning Trichoptera varies with reductions in some populations and enhancement in others. Simuliids are usually restricted, probably because of a lack of suitable oviposition or attachment sites. Freshets released from reservoirs increase the level of invertebrate drift. However, the full consequences of impoundment on drift, recolonization, and upstream migration have yet to be assessed. There is some evidence that modified temperature regimes cause extended egg hatching periods and alter larval growth rates but further studies are needed. Little is known of the effects of inter-river transfers on invertebrates, but it has been suggested that changes in flow velocity, water chemistry, suspended solids, and temperature together with translocation of organisms are all likely to be important. The limited information available for groundwater schemes indicates that they are not detrimental to invertebrates. Their impact, however, is dependent upon factors such as the extent and timing of flow augmentation. It is suggested that there is scope for positive management of invertebrate communities through river regulation, although at present attitudes and practices do not encourage this. Many gaps in our knowledge still remain and these are discussed in relation to future research needs. 相似文献
96.
DE Newby NE Goodfield AD Flapan NA Boon KA Fox DJ Webb 《Canadian Metallurgical Quarterly》1998,80(2):134-140
This study evaluated the effects of stimulus repetition rate, phase, and frequency on the auditory brainstem response (ABR) in normal-hearing neonates and adults. In both neonates and adults, the results clearly showed large ABR wave V latency differences between condensation and rarefaction for low-frequency stimuli. Phase dependent latency effects are believed to be a result of the phase-sensitive low-frequency neurons. Increasing stimulus repetition rate produced greater wave V latency shift in neonates than in adults. The consequences of rate changes were independent of stimulus phase and frequency. 相似文献
97.
98.
99.
The paper deals with the study of test generation mechanisms for faults on the intermediate lines using Boolean matrices. The proposed technique is a novel approach to the problem and also aims at deriving the results heuristically, thus saving computational effort. The technique has been illustrated by suitable examples. 相似文献
100.
The melting temperature of polyethylene was determined at pressures up to 30 kbar. Using these results and the calculated values of the volume change on melting in the Clausius–Clapeyron equation, the enthalpy and entropy of fusion as a function of pressure were also determined. 相似文献