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991.
W.D. Reekie 《Research Policy》1973,2(3):246-264
In this paper the patenting activity of the international pharmaceutical industry in London between 1900 and 1966 is analysed. Although patent data as a measure of industrial activity is not without defects it can be used both as an adjunct to and as a surrogate for more conventional yardsticks such as concentration ratios, sales statistics and so on. The results indicate that patenting activity can be used as both an absolute and relative indicator of an industry's pace of technological change. They help pinpoint the international distribution of pharmaceutical research and development. If analysed by product or process they can aid in the understanding of why an industry's competitive behaviour is or is not primarily one of price rivalry. Finally, they illustrate the continuing role of the individual inventor. 相似文献
992.
While there is no universal logic of induction, the probabilitycalculus succeeds as a logic of induction in many contexts throughits use of several notions concerning inductive inference. Theyinclude Addition, through which low probabilities representdisbelief as opposed to ignorance; and Bayes property, whichcommits the calculus to a refute and rescale dynamicsfor incorporating new evidence. These notions are independentand it is urged that they be employed selectively accordingto needs of the problem at hand. It is shown that neither isadapted to inductive inference concerning some indeterministicsystems.
- 1 Introduction
- 2 Failure of demonstrations of universality
- 2.1 Working backwards
- 2.2 The surface logic
- 3 Framework
- 3.1 The properties
- 3.2 Boundaries
- 3.2.1 Universalcomparability
- 3.2.2 Transitivity
- 3.2.3 Monotonicity
- 3.2.2 Transitivity
- 3.2 Boundaries
- 4 Addition
- 4.1 The property: disbelief versus ignorance
- 4.2Boundaries
- 5 Bayes property
- 5.1 The property
- 5.2 Bayes' theorem
- 5.3Boundaries
- 5.3.1 Dogmatism of the priors
- 5.3.2 Impossibilityof prior ignorance
- 5.3.3 Accommodation of virtues
- 5.3.2 Impossibilityof prior ignorance
- 5.2 Bayes' theorem
- 6Real values
- 7 Sufficiency and independence
- 8 Illustrations
- 8.1 All properties retained
- 8.2 Bayes propertyonly retained
- 8.3 Induction without additivity and Bayes property
- 8.2 Bayes propertyonly retained
- 9Conclusion
- 2 Failure of demonstrations of universality
993.
Jeffrey K. Uhlmann 《Journal of The Franklin Institute》2004,341(7):569-593
This paper examines some of the combinatorial issues associated with the batch data association problem arising in tracking and correlation applications. A procedure is developed that addresses a large class of data association problems involving the calculation of permanents of submatrices of the original association matrix. This procedure yields what is termed the Joint Assignment Matrix (JAM), which can be used to optimally rank associations for hypothesis selection. Because the computational cost of the permanent scales exponentially with the size of the matrix, improved algorithms are developed both for calculating the exact JAM and for generating approximations to it. Empirical results suggest that at least one of the approximations is suitable for real-time hypothesis generation in large scale tracking and correlation applications. Novel theoretical results include an improved upper bound on the calculation of the JAM and new upper bound inequalities for the permanent of general nonnegative matrices. One of these inequalities is an improvement over the best previously known inequality. 相似文献
994.
R. Shukia S. B. Sharma D. Puri K. M. Prabhu P. S. Murthy 《Indian journal of clinical biochemistry : IJCB》2000,15(1):169-177
Many plants have been used for the treatment of diabetes mellitus in Indian system of medicine and in other ancient systems of the world. Out of these only a few have been evaluated as per modern system of medicine. From many such plants only extracts have been prepared and their usefulness evaluated in experimental diabetes in animals. In some plants likeAllium cepa, Allium sativum, Ficus bengalensis, Gymnema sylvestre, Pterocarpus marsupium etc. active hypoglycemic principles have been isolated and their mechanism of action studied. Most of them seem to act directly on pancreas (pancreatic effect) and stimulate insulin level in blood. Some have extra pancreatic effect also by acting directly on tissues like liver, muscle etc. and alter favourably the activities of the regulatory enzymes of glycolysis, gluconeogenesis and other pathways. Since the plant products have less side effects, they have the potential as good hypoglycemic drugs. They may also provide clues for the development of new and better oral drugs for diabetes. 相似文献
995.
Globalization has contributed to the dismantling of national boundaries, which have enabled firms to compete and conduct business on a wider scale [Held, D., McGrew, A., Goldblatt, D., & Perraton, J. (1999). Global transformations. Politics, economics and culture. Cambridge: Polity Press]. Firms can move freely between different markets using Internet-based technology. While access to such markets can provide firms with greater choice of suppliers and cost efficiencies, they need to be aware of challenges that can influence their business performance. With this in mind, we examine how these factors influenced Alcoa Alumina's drive to a global procurement platform through a global marketplace. The staged adoption process experienced at Alcoa Alumina offers a learning opportunity for other firms considering the transition to global marketplace. 相似文献
996.
Rinchen D Bhutia Bhumika Upadhyay M Maneesh 《Indian journal of clinical biochemistry : IJCB》2006,21(2):39-41
The present study was designed to determine the association between extent of hepatocellular injury and plasma level of thiobarbituric
acid reactive substances (TBARS) in pre term infants with cholestasis. Preterm infants (<35 weeks gestation) admitted to the
neonatal intensive care unit were enrolled (with their parents informed consent) in either the ‘cholestasis’ group (if their
direct bilirubin was >2 mg/dl) (n=25) or in the control group (n=16). Blood samples for measurement of TBARS, direct bilirubin
and transaminases were obtained with-in 24 hours of enrollment. The cholestasis and control groups were comparable with respect
to gestational age, birth weight and Apgar score. Serum direct bilirubin, SGOT (EC 2.6.1.1) and SGPT (EC 2.6.1.2) levels were
significantly high in the cholestasis group. Plasma levels of TBARS in cholestasis group were correlated with SGOT (F=276.92;
P<0.0001) and SGPT (F=355.17; P<0.0001) and differed significantly between cholestatic and control infants. Our findings suggest
that oxidative stress in preterm infants with cholestasis is associated with hepatocellular injury. 相似文献
997.
B. Venkata Raman D. N. Rao T. M. Radhakrishnan 《Indian journal of clinical biochemistry : IJCB》2004,19(1):105-109
Enteromorpha compressa a marine green algal species grows extensively in North coastal Andhra Pradesh. Besides its nutritional importance it has
also been identified as source of anti-anaphylactic compound(s).E. compressa extracts alleviated the IgE levels raised against ovalbumin and other allergens in mice. Further,Enteromorpha extract also significantly down regulated the serum IgE levels in different murine models irrespective of their genetic background.
The results obtained in this study suggest thatE. compressa extract has compound(s), which inhibit IgE immune response and may have potential in curing various types of allergies. 相似文献
998.
Bhawana Nigam S. P. Joshi Seema Nagar Rajesh Chavan D. Pendharkar 《Indian journal of clinical biochemistry : IJCB》1996,11(2):124-128
The analysis of biochemical parameters in 162 patients with various neoplastic disorders along with 50 normal subjects showed significant rise in serum alkaline phosphatase and lactate dehydrogenase as compared to normal subjects. 21 patients with other monoclonal gammopathies which include infection and immunological diseases were also studied. Parameters such as serum calcium, uric acid, total protein, albumin and globulin were also analyzed in 42 (26%) cases of multiple myeloma, 27 (17%) cases of gastro-intestinal malignancies, 22 (14%) cases of urogenital malignancies, 11 (6%) cases of carcinoma breast, 4 (2%) cases of bone tumors, 21 (12%) cases of other monoclonal gammopathies, including 7 (4%) cases of infection and 14 (8%) cases of immunological diseases. The results indicate use of enzymes alkaline phosphatase and lactate dehydrogenase in neoplastic disorders. 相似文献
999.
1000.
A theory is developed to describe the propagation of characteristics waves through an infinite slab of irregularities in a magneto-ionic medium. The theory makes use of the asymptotic Green's dyadic. The results show that mode conversion is possible through scattering from irregularities in an anisotropic background. Some special cases are discussed and an example is given. 相似文献