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391.
Subcutaneous administration of monosodium glutamate (MSG), to normal adult male mice, for six consecutive days at dose levels
of 4 and 8 mg/g body weight, significantly increased the level of free radical initiating enzyme, xanthine oxidase, whereas
the activity of free radical scavenging enzymes, like catalase and superoxide dismutase was significantly decreased in hepatic
tissue. These observations suggested that ingestion of MSG at dose level of 4 mg/g body weight and above, induced oxidative
stress in the hepatic tissue of adult male mice. 相似文献
392.
Singh JA 《Endeavour》2008,32(1):5-9
It is a decade since the exposure of Project Coast, apartheid South Africa's covert chemical and biological warfare program. In that time, attention has been focused on several aspects of the program, particularly the production of narcotics and poisons for use against anti-apartheid activists and the proliferation of both chemical and biological weapons. The eugenic dimension of Project Coast has, by contrast, received scant attention. It is time to revisit the testimony that brought the suggestion of eugenic motives to light, reflect on some of the Truth and Reconciliation Commission's findings and search for lessons that can be taken from this troubled chapter in South Africa's history. 相似文献
393.
394.
We have studied the effect of flap parameters on fluid rectification in a microfluidic diode. We use Navier-Stokes equations and arbitrary Lagrangian-Eulerian formulation to obtain dynamics of fluid flow and motion of the flap. The flap opens during forward flow and seals against a stopper during reverse flow. This allows flow in the forward direction and prevents it in the reverse direction. The rectifier is fluidic analog to a semiconductor diode in function because it rectifies fluid flow. Velocity-pressure (V-P) curves analog to the current-voltage (I-V) curves of the electronic diode has been obtained. The effect of the flap parameters, such as length, thickness, and Young's modulus has been found out. The transient response of the flap and fluid flow under oscillating pressure driven flow has also been obtained. 相似文献
395.
Goswami B Singh B Chawla R Gupta VK Mallika V 《Indian journal of clinical biochemistry : IJCB》2010,25(4):376-379
Laboratory analytical turnaround time is a reliable indicator of laboratory effectiveness. Our study aimed to evaluate laboratory
analytical turnaround time in our laboratory and appraise the contribution of the different phases of analysis towards the
same. The turn around time (TAT) for all the samples (both routine and emergency) for the outpatient and hospitalized patients
were evaluated for one year. TAT was calculated from sample reception to report dispatch. The average TAT for the clinical
biochemistry samples was 5.5 h for routine inpatient samples while the TAT for the outpatient samples was 24 h. The turnaround
time for stat samples was 1 h. Pre- and Post-analytical phases were found to contribute approximately 75% to the total TAT.
The TAT demonstrates the need for improvement in the pre- and post-analytical periods. We need to tread the middle path to
perform optimally according to clinician expectations. 相似文献
396.
Parmjit Singh 《Educational Studies in Mathematics》2000,43(3):271-292
The purpose of this study was to construct an understanding of two grade six students' proportional reasoning schemes. The
data from the clinical interviews gives insight as to the importance of multiplicative thinking in proportional reasoning.
Two mental operations, unitizing and iterating play an important role in student's use of multiplicative thinking in proportion
tasks. Unitizing a composite unit and iterating it to its referent point enables one to preserve the invariance of a ratio.
Proportions involved the coordination of two number sequences, keeping the ratio unit invariant under the iteration. In the
iteration process, one needed to explicitly conceptualize the iteration action of the composite ratio unit to make sense of
ratio problems and to have sufficient understanding of the meaning of multiplication and division and its relevance in the
iteration process. One needed to have constructed multiplicative structures and iteration schemes in order to reason proportionally.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
397.
Health benefits of Kung Fu: a systematic review 总被引:1,自引:1,他引:0
The Chinese martial arts (Kung Fu) have existed for centuries and are generally accepted as being beneficial for health without much empirical data. The aim of this systematic review was to assess the health effects of "hard" Kung Fu styles by performing electronic and manual searches of the literature. The aspects of health and the Kung Fu style examined varied between most studies; in some cases, the martial art group consisted of practitioners of other martial art styles also. Of 2103 references identified, only nine papers were eligible and reviewed. All were observational studies, observing a range of health aspects possibly related to Kung Fu training or performance. Our findings suggest that there is no evidence that Kung Fu practice is associated with the prevention or treatment of any health condition. However, as a moderate- to high-intensity form of aerobic exercise, it may confer benefits similar to those attributed to other aerobic training modalities. However, this hypothesis remains to be tested in clinical trials. Physiological benefits (e.g., aerobic capacity and bone density) may be associated with long-term Kung Fu practice. Future research in this area should adopt experimental designs, clearly identifying eligibility criteria, testing and training protocols, and include health-related outcomes and documentation of adverse events, to advance knowledge in this field. 相似文献
398.
399.
400.
B. K. Jain Daljit Singh Harmesh Singh A. P. S. Narang Praveen C. Sobti Ajay Gupta 《Indian journal of clinical biochemistry : IJCB》2000,15(1):36-39
Serum total and ionised calcium levels were measured at birth and at 48 hours in 25 term neonates with birth asphyxia (one
minute APGAR score of 6 or less) and in 25 normal term neonates (one minute APGAR score of 7 or more). Infants were categorised
into two groups TAGA (term appropriate for gestational age) and TSGA (term small for gestational age). Asphyxiated infants
had significantly lower serum total and ionised calcium values at birth as well as at 48 hours. Abnormal clinical features
were observed in 48% of asphyxiated infants. Low ionised calcium was detected in symptomatic babies, who had otherwise normal
total calcium values. Due to hyocalcemia especially ionised calcium in asphyxiated infants and high frequency of functional
derangement associated with this hypocalcemioa, serial monitoring of serum isonised calcium levels is necessary. 相似文献