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Human C4b-binding protein (C4BP) functions as a cofactor to factor I in the degradation of C4b and accelerates the decay rate of the C4b2a complex. In this study we describe a monoclonal antibody directed against the alpha-chain of C4BP that inhibits the binding of C4b to C4BP. In order to identify the structural domain of the alpha-chain of C4BP that interacts with C4b, tryptic fragments of C4BP were generated. Amino acid sequence analysis of the fragments revealed that the residues Ser333-Arg356 of the alpha-chain of C4BP contain the epitope of this antibody, and as a consequence, that this part of the alpha-chain of C4BP is likely to be involved in the interaction with C4b.  相似文献   
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Forests are the chief resource for the collection and exploration of biological materials. The past few decades have witnessed a large scale deforestation in India due to substantial pressures generated by population growth, leading to demand for more land for agriculture, urbanization and industrial activities, in addition to increased demand for fuel wood and timber. This has resulted in the loss of soil cover, habitat destruction, environmental degradation and ecological imbalance. This scenario has created a progressive awareness for the conservation and restoration of habitats and, thus, the declaration of many forest areas into protected zones, such as national parks, biosphere reserves, etc., including the protection of some marine areas, by both the National and State Governments. Normally, permission for biological collecting is not granted in these protected areas. In India, forests are a State subject and grant for collection permission is vested with the State Forest Departments. In the absence of any rules, regulations and guidelines, either from National or State Governments, forest authorities impose their terms and conditions, which are arbitrary and even contradictory at times, in the process of granting collecting permits. A set of new rules to be applied throughout the country is needed.  相似文献   
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A physiological role for paraoxonase (PON1) is still uncertain, but it catalyzes the hydrolysis of toxic organophosphates. Evidence that the human genome contains two PON1-like genes, designated PON2 and PON3, is presented here. Human PON1 and PON2 each have nine exons, and the exon/intron junctions occur at equivalent positions. PON1 and PON2 genes are both on chromosome 7 in human and on chromosome 6 in the mouse. Turkey and chicken, like most birds, lack paraoxonase activity and are very susceptible to organophosphates. However, they have a PON-like gene with approximately 70% identity with human PON1, PON2, and PON3. Another unexpected finding is that the deduced amino acid sequences of PON2 in human, mouse, dog, turkey, and chicken and of human PON3 are all missing the amino acid residue 105, which is lysine in human PON1. The expanded number of PON genes will have important implications for future experiments designed to discover the individual functions, catalytic properties, and physiological roles of the paraoxonases.  相似文献   
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A methodology for the analysis and design of fall sequences of robots that minimize joint/articulation injuries, and the damage of valuable body parts is proposed. These fall sequences can be activated/triggered by the robot in case of a detected unintentional fall or an intentional fall, which are common events in humanoid soccer environments. The methodology is human-based and requires the use of a realistic simulator as development tool. The obtained results show that fall sequences designed using the proposed method produce less damage than standard, uncontrolled falls.  相似文献   
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Forty patients with temporal epilepsy were operated on with a stereotaxic technique. Eleven patients had a unilateral localization of the epileptic focus, and in 29 bitemporal foci were diagnosed. In evaluating the results of the treatment the dynamics of the epileptic fits, the peculiarities of changes in the mental status, and the degree of social adaptation were taken into consideration. A postoperative improvement was achieved in 73% of the patients with monotemporal lesions, while in those with bitemporal epilepsy and distinct persistent mental disorders the state was improved in 44% of the cases. Indications for the choice of the zone of destruction depending on the clinical peculiarities of the lesion are presented.  相似文献   
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