Given a finite set F of functions and a learning sample, the aim of an aggregation procedure is to have a risk as close as possible to risk of the best function in F . Up to now, optimal aggregation procedures are convex combinations of every elements of F . In this paper, we prove that optimal aggregation procedures combining only two functions in F exist. Such algorithms are of particular int...

To examine the temporal effects of plasmin generated in vivo on platelet function, we infused tissue-type plasminogen activator (t-PA) in rabbits over 3 hours and measured ex vivo platelet aggregation. We noted an initial increase in the aggregation response to ADP occurring 30 minutes after the start of infusion. This enhanced response was short-lived and by 180 minutes was reduced, compared w...

Platelet aggregation inhibitory effect and anticoagulant properties of fractions separated from the venoms of Cerastes persicus fieldi and Echis carinatus were investigated. The partial fractionation was performed on a Sephadex G-100 column. Two fractions separated from Cerastes persicus fieldi showed anti platelet aggregation activity on ADP (200 µM)-induced platelet aggregation (ca 80% inhibi...

To examine the temporal effects of plasmin generated in vivo on platelet function, we infused tissue-type plasminogen activator (t-PA) in rabbits over 3 hours and measured ex vivo platelet aggregation. We noted an initial increase in the aggregation response to ADP occurring 30 minutes after the start of infusion. This enhanced response was short-lived and by 180 minutes was reduced, compared w...

platelet aggregation inhibitory effect and anticoagulant properties of fractions separated from the venoms of cerastes persicus fieldi and echis carinatus were investigated. the partial fractionation was performed on a sephadex g-100 column. two fractions separated from cerastes persicus fieldi showed anti platelet aggregation activity on adp (200 µm)-induced platelet aggregation (ca 80% inhibi...

Background: Targeting of CD20 antigen with monoclonal antibodies has become the mainstay in the treatment of non-Hodgkin's lymphomas and immunotherapeutic depletion of malignant B cells. Accessibility of antigen is one of the crucial factors in development of monoclonal antibodies against this antigen. One major problem in expression of full length CD20 is aggregation and misfolding. Therefore,...

Epidemiologic studies show that the cardiovascular diseases are associated with multiple factors such as raised serum total cholesterol, increased LDL, increased platelet aggregation, hypertension and smoking. In-vitro studies have confirmed the ability of some plants of Allium species to reduce these parameters. Therefore, we evaluated anti-platelet aggregation effect of some Allium species (A...

A series of novel 2-aminopyrimidine and 2-Substituted-4,6-diaminopyrimidine derivatives have been synthesized and their anti platelet aggregation activities were assessed against ADP and arachidonic acid- induced platelet aggregation in human plasma using light transmission aggregometry. None of the compounds showed satisfactory activity against the aggregation induced by ADP. However, satisfac...

The aggregation of alpha synuclein (α-syn) is a neuropathological feature that defines a spectrum of disorders collectively termed synucleinopathies, and of these, Parkinson's disease (PD) is arguably the best characterized. Aggregated α-syn is the primary component of Lewy bodies, the defining pathological feature of PD, while mutations or multiplications in the α-syn gene result in familial P...

We investigated rheological adaptation of leukocytes and platelets for their adhesive functions in inflammation and hemostasis, respectively. Adhesion and margination of leukocytes or platelets were quantified for blood perfused through capillaries coated with P-selectin or collagen, when flow rate, suspending phase viscosity, red cell aggregation, or rigidity was modified. Independent variatio...