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911.
Ritu Sharma Mridula Mahajan Ravi Kant 《Indian journal of clinical biochemistry : IJCB》2004,19(1):10-13
Serum total lipids (cholesterol and triglyceride), lipoproteins (VLDL, LDL and HDL) and Apolipoprotein-B levels of normal
healthy individuals (n=25) and coronary artery disease patients (n=25) were estimated. The objective of the present study
was to ascertain the role of apo-B in causation and inheritance of coronary artery disease. It was observed that on an average
serum total cholesterol and triglyceride more than 200 mg/dl bring the individuals to a risk of coronary artery disease (CAD)
irrespective of the age. CAD patients achieved this value at an early age (35–45 years). Similarly VLDL and LDL levels were
found to be significantly raised in CAD patients when compared to that of age matched normal individuals, with patients achieving
risk values at an early age. HDL levels were found to be significantly lower in CAD patients as compared to normal individuals.
Serum apo-B levels were significantly raised in CAD patients as compared to age matched normal individuals. Patients with
positive family history of CAD had raised serum apo-B levels than those having negative family history. A positive coefficient
of correlation was observed between serum apo-B and LDL levels suggesting that more the number of Apo-B particles, more will
be the synthesis of atherogenic particle (LDL). Patients with negative family history had serum apo-B levels closer to those
of normal individuals and in these individuals HDL levels were found to be significantly lowered, suggesting that loss of
scavenger role of HDL could be the risk factor responsible for the causation of CAD in these patients, with negative family
history of coronary artery disease. 相似文献
912.
R. Kumar R. Kapoor B. Mittal A. Kumar R. D. Mittal 《Indian journal of clinical biochemistry : IJCB》2003,18(2):209-215
Metabolic abnormalities were investigated in 44 stone patients with first time (group 1) and 56 with 2 times stone formation
(group 2), and in 25 normal individuals. 24hr urine was analysed spectrophotometrically for oxalate, calcium, magnesium, citrate,
uric acid, phosphate and creatinine. Hypocitraturia and hyperoxaluria were the common abnormalities in the stone formers.
Stone patients had significantly higher urinary oxalate, calcium and uric acid and lower phosphate than normal individuals.
Citrate/calcium and magnesium/calcium ratio were significantly high in normal individuals than stone formers. Patients in
group 2 excreted significantly higher urinary calcium and lower citrate that patients in group 1. Citrate/calcium ratio was
higher in group 1 than group 2. Hypocitraturia, hyperoxaluria, hypercalciuria and increased citrate/calcium and magnesium/calcium
ratio seem to be an essential risk factor for stone formation. Patients with recurrent stone formation could be distinguished
from patients with first time stone formation on the basis of urinary calcium and citrate. 相似文献
913.
In this article we propose that medical practice evolves as a result of progress along three different pathways: improvement in the ability to develop effective medical technologies, learning in medical practice, and advances in biomedical scientific understanding of disease. The relative importance of these three pathways varies from case to case, and often they interact strongly. More specifically, we argue here that in cases of therapeutic innovation where a new medical technology is involved the advance in medical practice is driven largely by the ability to develop and use effective medical artifacts and the interactive sequence among these interdependent pathways often starts with what is learned in practice and not in science. While we state this argument in general, we develop it in detail in a longitudinal and contextual case study of the emergence and evolution of a treatment for advanced heart failure based on an implantable device, the Left Ventricular Assist Device (LVAD). Our findings show that an essential aspect of the evolution of the LVAD therapy is collective and cumulative learning that requires experience that only can be gained through the actual use of LVADs. We discuss the theoretical and policy implications that follow from our understanding of how medical practice evolves for research on the evolution of medical practices and new medical technologies, and policies about the evaluation of rapidly moving medical practices and clinical research involved in their advancement. 相似文献
914.
A simple experimental setup to study the impact and coalescence of deposited droplets is described. Droplet impact and coalescence have been investigated by high-speed particle image velocimetry. Velocity fields near the liquid-substrate interface have been observed for the impact and coalescence of 2.4 mm diameter droplets of glycerol∕water striking a flat transparent substrate in air. The experimental arrangement images the internal flow in the droplets from below the substrate with a high-speed camera and continuous laser illumination. Experimental results are in the form of digital images that are processed by particle image velocimetry and image processing algorithms to obtain velocity fields, droplet geometries, and contact line positions. Experimental results are compared with numerical simulations by the lattice Boltzmann method. 相似文献
915.
This paper deals with the problem of adaptive output feedback neural network controller design for a SISO non-affine nonlinear system. Since in practice all system states are not available in output measurement, an observer is designed to estimate these states. In comparison with the existing approaches, the current method does not require any information about the sign of control gain. In order to handle the unknown sign of the control direction, the Nussbaum-type function is utilized. In order to approximate the unknown nonlinear function, neural network is firstly exploited, and then to compensate the approximation error and external disturbance a robustifying term is employed. The proposed controller is designed based on strict-positive-real (SPR) Lyapunov stability theory to ensure the asymptotic stability of the closed-loop system. Finally, two simulation studies are presented to demonstrate the effectiveness of the developed scheme. 相似文献
916.
Miriam Delgado-Verde Javier Amores-Salvadó Gregorio Martín-de Castro José Emilio Navas-López 《知识管理研究与实践》2014,12(3):261-275
Although the importance of intellectual capital has already been highlighted in the management literature, few articles have focused on the importance of its green counterpart, green intellectual capital. Nowadays, when environmental concerns cannot be ignored by firms, it is therefore time to explore the role of green intellectual capital in environmental improvement. For that reason, our research aims to explore the relationships between green intellectual capital components and the environmental performance of the firms. In particular, we try to show the importance of green organizational and social capital in the development of environmental product innovations, which are vital to the development and implementation of environmental strategies since, as scholars have pointed out, they generate some of the greatest environmental impacts. The empirical results show that green organizational capital has an indirect impact on environmental product innovation through green social capital, meaning that the latter is a significant mediator of that relationship, and at the same time emphasizing that informal relationships play a key role in the improvement of the environmental performance of the firm and, more specifically, in the development of environmental product innovations. 相似文献
917.
Real options analysis was often recommended as an emerging valuation technique for high-risk investment projects. Former inter-sectoral surveys have drawn an ambivalent picture of real options usage in general. In addition, there is a lack of sector-specific investigations. In the following article the results of an in-depth analysis of collected empirical data regarding the application of this new tool in the pharmaceutical sector is presented by capturing the internal view from the pharmaceutical companies themselves and the external view from the health care departments of financial service firms. R&D stage specific modi of application, reasons for reluctance in the employment of real options and their assumed future prospects are elucidated. 相似文献
918.
David Nicholas Paul Huntington Hamid R. Jamali Anthony Watkinson 《Information processing & management》2006
The article employs deep log analysis (DLA) techniques, a more sophisticated form of transaction log analysis, to demonstrate what usage data can disclose about information seeking behaviour of virtual scholars – academics, and researchers. DLA works with the raw server log data, not the processed, pre-defined and selective data provided by journal publishers. It can generate types of analysis that are not generally available via proprietary web logging software because the software filters out relevant data and makes unhelpful assumptions about the meaning of the data. DLA also enables usage data to be associated with search/navigational and/or user demographic data, hence the name ‘deep’. In this connection the usage of two digital journal libraries, those of EmeraldInsight, and Blackwell Synergy are investigated. The information seeking behaviour of nearly three million users is analyzed in respect to the extent to which they penetrate the site, the number of visits made, as well as the type of items and content they view. The users are broken down by occupation, place of work, type of subscriber (“Big Deal”, non-subscriber, etc.), geographical location, type of university (old and new), referrer link used, and number of items viewed in a session. 相似文献
919.
920.
Anders Albrechtslund 《Ethics and Information Technology》2007,9(1):63-72
This article offers a discussion of the connection between technology and values and, specifically, I take a closer look at
ethically sound design. In order to bring the discussion into a concrete context, the theory of Value Sensitive Design (VSD)
will be the focus point. To illustrate my argument concerning design ethics, the discussion involves a case study of an augmented
window, designed by the VSD Research Lab, which has turned out to be a potentially surveillance-enabling technology. I call
attention to a “positivist problem” that has to do with the connection between the design context and the use context, which
VSD seems to presuppose, and I argue that it is necessary to clearly distinguish between the two, since the designers’ intentions
do not always correspond with the users’ practice; in fact, the relation between design and use is very complex and principally
unpredictable. Thus, a design theory must accept that foresight is limited to anticipation rather than prediction. To overcome
the positivist problem, I suggest a phenomenological approach to technology inspired by Don Ihde’s concept of multistability.
This argument, which is general in nature and thus applies to any theory of design ethics, is intended as a constructive criticism,
which can hopefully contribute to the further development of design ethics. 相似文献