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101.
Serum alpha-1-antitrypsin assay was carried out in 21 smokers (mean age 44±8 yrs) and in 25 nonsmokers (mean age 44±7 yrs). The levels of serum alpha-1-antitrypsin expressed in umol/mt/ml were 2.97±0.85 for smokers and 3.08±0.37 for non-smokers and analysis of variance revealed no significant difference between these two groups. However in five smokers reduced levels (<80% of the lower limit of non-smokers) were seen and four of them were bus drivers. This study advises monitoring of serum alpha-1-antitrypsin levels in smokers with possible therapy to those with reduced levels.  相似文献   
102.
New necessary and sufficient conditions, which are also algorithmic in nature, are obtained for the decomposition of a multivariable reactance function or a multivariable positive real function into a sum of several single variable reactance functions or several single variable positive real functions, respectively.  相似文献   
103.
Calcium plays an important role in the pathophysiology of essential hypertension. Serum calcium levels were measured in 117 subjects with essential hypertension and 77 first-degree relatives. The results showed that serum calcium levels were significantly (p<0.01) decreased in both males and females with essential hypertension and their first-degree relatives when compared with the normotensive controls. This is the first study in Indian population.  相似文献   
104.
Policy reflects and shapes society's beliefs about schools, teachers, children, learning, and society, as well as the power structures embedded in our communities and decision-making processes. Although teachers may be central to the implementation of education policy, they are marginal to the design of policy agendas and text, especially around issues of teaching and learning. Their absence in the policymaking process creates a disconnect between the goals and design of education policy and the actual lived challenges of implementation. In examining the dynamics in this critical disconnect, we address the following research questions: How do institutional norms and routines affect teachers' agency in the policymaking process? Following this research question is our action question: How do we support conditions that support teachers as policy agents? We draw on qualitative data from two sites (West Virginia and Wisconsin) where K–12 teachers partnered with university researchers in a range of capacity-building efforts. Analysis illustrates how teachers interact with certain institutional norms that make it hard to engage in policy design. Based on our findings, we discuss how a teacher–university partnership can better support the conditions that facilitate greater teacher agency in thinking, talking, and acting on policy.  相似文献   
105.
V. U. Reddy 《Resonance》1998,3(10):79-88
Fast Fourier transform (FFT) is an efficient algorithm for computing the discrete Fourier transform. The discovery of the FFT algorithm paved the way for widespread use of digital methods of spectrum estimation which influenced the research in almost every field of engineering and science. In this article, we will first introduce the continuous-time Fourier transform (CFT), discretetime Fourier transform and discrete Fourier transform (DFT) and then present an example to illustrate the relation between CFT and DFT. In particular, we bring out the fact that the DFT is a tool to estimate the samples of the CFT at uniformly spaced frequencies. Next, we introduce the FFT algorithm giving certain key steps in its development.  相似文献   
106.
The primary role of the shoulder joint in tennis forehand drive is at the expense of the loadings undergone by this joint. Nevertheless, few studies investigated glenohumeral (GH) contact forces during forehand drives. The aim of this study was to investigate GH compressive and shearing forces during the flat and topspin forehand drives in advanced tennis players. 3D kinematics of flat and topspin forehand drives of 11 advanced tennis players were recorded. The Delft Shoulder and Elbow musculoskeletal model was implemented to assess the magnitude and orientation of GH contact forces during the forehand drives. The results showed no differences in magnitude and orientation of GH contact forces between the flat and topspin forehand drives. The estimated maximal GH contact force during the forward swing phase was 3573 ± 1383 N, which was on average 1.25 times greater than during the follow-through phase, and 5.8 times greater than during the backswing phase. Regardless the phase of the forehand drive, GH contact forces pointed towards the anterior-superior part of the glenoid therefore standing for shearing forces. Knowledge of GH contact forces during real sport tasks performed at high velocity may improve the understanding of various sport-specific adaptations and causative factors for shoulder problems.  相似文献   
107.
108.
WHO-Tropical Disease Research scheme highlighted the need for development of new anti-filarial drugs. Certain antibiotics have recently been found effective against Wolbachia, co-existing symbiotically with filarial parasites. Inflammatory response entails oxidative mechanism to educe direct anti-microbial effect. In the present study microfilariae were maintained in vitro in medium supplemented with varying concentrations of tetracycline, doxycycline (20–100 μg/ml) or ciprofloxacin (50–250 μg/ml) separately to find out any involvement of oxidative mechanism in the anti-filarial effect of these antibiotics. Loss of motility of the microfilariae was measured after 48 h and correlated with the levels of MDA, nitric oxide and protein-carbonylation. Significant loss of microfilarial motility was recorded with increasing concentration of tetracycline and doxycycline but with ciprofloxacin the effect was not marked. Agents with high antifilarial activity revealed significant association with oxidative parameters in a dose dependent manner. The result suggests that oxidative effect might be exploited to design novel antifilarial drug candidate.  相似文献   
109.
Plasma levels of lipids, lipoproteins and lipid peroxides and erythrocyte Na+−K+ ATPase, Mg2+ATPase and antioxidant enzymes were measured in type-2 diabetic patients. A significant decrease in Na+-K+-ATPase activity was observed in diabetic patients which was negatively correlated with blood glucose and lipid peroxides, while the Mg2+-ATPase activity was increased. In the diabetic subjects the plasma concentrations of Na+ and K+ were increased where as erythrocyte levels of Na+ were increased and K+ were decreased. Hyperlipidaemia and increased levels of lipid peroxides were observed in the diabetic subjects. There was a significant increase in erythrocyte catalase activity in diabetics which positively correlated with their lipid peroxides. There was no change in GPx activities between controls and diabetics.  相似文献   
110.
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