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681.
In an increasingly globalizing and knowledge-based world economy, the declining importance of R&D activity in India is a matter of concern. This paper analyzes the determinants of R&D behaviour of Indian enterprises over the 1990s in the context of the reforms of 1991 and their impact on the R&D behaviour of MNE affiliates and local enterprises. The analysis suggests that although average levels of spending have fallen, increased competition due to liberalization seems to have pushed local firms to rationalize their R&D activity and make it more efficient. Also, R&D spending seems to rise more than proportionally with firm size after a certain threshold level has been reached. The analysis brings out differences in the nature of R&D activity of MNE affiliates and local firms. Local firms direct their R&D activity primarily towards the assimilation of imported technology, and to providing a backup to their outward expansion via exports and FDI. MNE affiliates, on the other hand, focus on exploiting the advantages of India as an R&D platform for their parents. The paper is concluded with some policy implications of the findings. 相似文献
682.
A. S. Bhatia Satish Kumar B. C. Harinath 《Indian journal of clinical biochemistry : IJCB》2003,18(2):1-5
Tuberculosis is still a major health problem in most developing countries and its incidence is rising in many developed countries.
This resurgence has been attributed to the HIV epidemic and TB has been declared as a global health emergency by WHO in 1993.
The diagnosis of tuberculosis mainly depends upon initial clinical suspicion and radiographic findings with subsequent bacteriological
confirmation by sputum smear examination and culture. Lack of sensitivity in smear examination, non specificity of radiological
findings, extended tum around time ofMycobacterium tuberculosis culture and difficulties in diagnosing paucibacillary, childhood and extrapulmonary tuberculosis has necessitated to explore
the utility of immunodiagnosis of tuberculosis as a convenient and cost effective test to supplement clinical information
for definite diagnosis. Many commercial tests are available in the market for diagnosis of TB. Most of these tests are based
on the detection of IgG, IgA and IgM antibodies to specific mycobacterial antigen or mixture of antigens. Indigenous immunoassay
systems have explored excretory-secretory ES-31 mycobacterial antigen for immunodiagnosis of TB. Many a time there is lack
of consistent elevation in all the three Ig classes in active infection thus making it more important to determine the ideal
antibody isotype assay for reliable diagnosis of tuberculosis and to save the costs of the patient for unnecessary investigations. 相似文献
683.
Swati Banerjee Sonika Gupta Niraj Shende Satish Kumar Bhaskar C. Harinath 《Indian journal of clinical biochemistry : IJCB》2003,18(2):48-53
Serodiagnosis by ELISA has been widely explored over the years, in the diagnosis of tuberculosis. Two ELISA systems were evaluated
for detection of mycobacterial antibodies in pulmonary and extra pulmonary tuberculosis. The two test assays explored were
ERBA LISA (TB IgG) test (Anda Biologicals) which uses A60 antigen complex found in the cytosol of typical and atypical mycobacteria,
and SEVA TB (IgG) ELISA, which uses a 31 kDa, glycoprotein antigen purified fromM. tb H37Ra culture filtrate. Sera from 98 proven tuberculosis [pulmonary TB (48), tuberculous lymphadenopathy (30), tuberculous meningitis
(15) & genitourinary TB (5)] were studied along with 32 healthy controls. The overall positivity obtained using ERBA LISA
(TB IgG) test and SEVA TB (IgG) ELISA test was 72.9% and 91.6% in pulmonary tuberculosis, 43.3% and 76.6% in tuberculous lymphadenopathy
respectively. The sensitivity of ERBA LISA test in tuberculous meningitis and genito-urinary TB was significantly low (26.6%
& 40% respectively) compared to sensitivity obtained using SEVA TB ELISA (86.6% & 60% respectively) with overall specificity
of 60% and 87.5%. Thus SEVA TB IgG ELISA test was found to be more sensitive than ERBA LISA in detecting IgG antibodies in
tuberculous sera, in particular in extra pulmonary tuberculosis cases. 相似文献
684.
Rahat Kumar Narinder Singh Kartar Singh Atul Kalhan K. K. Prasad 《Indian journal of clinical biochemistry : IJCB》2004,19(1):122-128
The normal coagulation process is initiated by disruption and exposure of the subendothelial components of blood vessels.
Platelets adhere to subendothelium-bound von Willebrand factor via glycoprotein (GP) Ib complex. This initial interaction
per se and the release of platelet agonists transduce signals that leads to the rise in intracellular Ca2+ which induces shape
change, prostaglandin synthesis, release of granular contents and conformational changes in platelet Gp IIb-IIIa. Gp IIb-IIIa
in activated platelets binds fibrinogen and other adhesive proteins and mediates platelet cohesion the primary haemostatic
plug. Furthermore, the activated platelets due to aggregation, result in the formation of fibrin (secondary hemostasis). Normally
the haemostatic process plays a delicate balance between keeping the blood in the fluid state to maintain flow and rapidly
forming an occluding plug following vessel injury. Thrombosis occurs because of alteration in this delicate balance. Arterial
thrombosis occurs in the setting of previous vessel wall injury mostly because of atherosclerosis, while venous thrombosis
occurs in areas of stasis. The recent advances in understanding of the haemostatic process have led to a better understanding
of the mechanism of action of many antithrombotic drugs and identification of new targets for drug development. The molecular
target of the ticlopidine has been identified. Large numbers of IIb-IIIa inhibitors have been developed. The mechanism of
action of heparin has been defined at the molecular level. As a result, a synthetic pentasaccharide, based on antithrombin-binding
domain of heparin, has been developed and tested successfully in clinical trials. New generation direct thrombin inhibitors
are being developed. Factor Xa has a critical position at the convergence of intrinsic and extrinsic pathway. The clinical
tolerability and the efficacy of low molecular weight heparins has established that inhibition of further thrombin generation,
by blocking factor Xa alone can be an effective way of preventing thrombus growth without inactivating thrombin. A large number
of specific factor Xa inhibitors are under development. Some of these are in preliminary clinical trials and appear to be
promising. Future clinical trials will determine whether these new drugs will provide better risk-benefit ratio in treatment
of thrombotic disorders. Similarly role of thrombolytics has been clearly established in many diseases including coronary
artery disease. 相似文献
685.
2008年11月,团购网站Groupon在美国成立——其命名由团体(group)和优惠券(coupon)合并而来——网上团购风马上席卷全美,而今更在全世界遍地开花。团购是继偷菜和微博之后又一个成为国人现实生活一部分的网络新生事物,在繁荣发展之余也产生了不少消费纠纷。3·15临近,小编提醒各位团友:团购有风险,点击要谨慎! 相似文献
686.
The authors investigated the use of student‐initiated e‐mail as a supplemental modality for supervision. Nineteen students e‐mailed their instructors weekly during their 15‐week practicum; these e‐mails were analyzed across 3 time periods using the categories of the discrimination model (J. M. Bernard, 1979, 1997) and an adaptation of W. Lanning's (1986) professional behavior category. Although patterns of e‐mails were similar across time, there was a significant decline in the number of e‐mails as the practicum progressed. Significance was found for message focus, with personalization messages and professional behavior/practicum class messages accounting for more than half of the messages across 3 time periods. 相似文献
687.
This paper examines stability and change during the elementary-to-middle school transition, focusing on adolescents’ experiences of home–school dissonance because of real or perceived differences between home/self and values within the school context. Relationships were hypothesized between exacerbation and amelioration of dissonance, middle school mastery and performance goal practices, and students’ perceptions thereof. The sample consisted of 274 African-American and 284 European-American (49% female) students. Middle school teachers (N = 236) provided data on school academic practices. Multilevel growth curve analysis indicated significant variance among the 10 middle schools regarding change in dissonance. Both mastery-focused middle school practices and students’ perception of middle school classrooms as more performance and less mastery focused than elementary classrooms were significant predictors of change in dissonance. Path-analyses evidence pointed to the mediational role of school belonging on the relationship between perception of classroom mastery goals and dissonance. Path analyses revealed direct and indirect effects of perception of classroom performance goals on dissonance and school belonging. This paper highlights the importance of creating inclusive learning environments that minimize social comparison saliency and validate students for who they are. 相似文献
688.
The semiconductor industry operates in a constant state of deflation. It is vital to our survival and progress in this knowledge era. The industry is extremely competitive and requires ongoing technological advances to improve performance while reducing costs to remain competitive. Gaining an understanding of important facets of this industry is essential. Besides knowing about semiconductor history, other aspects of interest include types of semiconductor products in the marketplace and their uses, typical semiconductor-chip making process, overall industry review and trends. One critical tool used by the industry to direct product and technology development is a technology roadmap. Review of the initial and current semiconductor technology roadmap would further enhance our understanding of semiconductor industry. 相似文献
689.
The chemical modifications that occur during vulcanization of rubber and methods for controlling the process are discussed. 相似文献
690.
Online learning from video modeling examples, in which a human model demonstrates and explains how to perform a learning task, is an effective instructional method that is increasingly used nowadays. However, model characteristics such as gender tend to differ across videos, and the model-observer similarity hypothesis suggests that such characteristics may affect learning. Therefore, this study investigated whether the effectiveness of learning how to solve a probability calculation problem from video modeling examples would vary as a function of the model’s and observer’s gender. In a 2 (Model: Female/Male) × 2 (Observer: Female/Male) between-subject design, 167 secondary education students learned how to solve probability calculation problems by observing video modeling examples. Results showed no effects of Model or Observer gender on learning and near transfer. Male students reported higher self-efficacy than female students. Compared to a female model, observing a male model enhanced perceived competence more from pretest to posttest, irrespective of observers’ gender. Furthermore, learning from a male model was less effortful and more enjoyable for male students than for female students. These results suggest that gender of both model and observer can matter in terms of affective variables experienced during learning, and that instructional designers may want to consider this when creating (online) learning environments with video modeling examples. 相似文献