Let <em>X</em>(<em>K</em>) &sub; <strong>P</strong>^<em>n</em> (<em>K</em>) be a projective algebraic variety over <em>K</em>, and let <em>D</em> be a subset of <strong>P</strong>^<em>n</em>_<em>OK</em> such that the codimension of <em>D</em> with respect to <em>X</em> &sub; <strong>P</strong>^<em>n</em>_<em>OK</em> is two. We are interested in points <em>P</em> on <em>X</em>(<em>K</em>) with the property that the intersection of the closure of <em>P</em> and <em>D</em> is empty in <strong>P</strong>^<em>n</em>_<em>OK</em>, we call such points <em>D</em>-integral points on <em>X</em>(<em>K</em>). First we prove that certain algebraic varieties have infinitely many <em>D</em>-integral points. Then we find an explicit description of the complete set of all <em>D</em>-integral points in projective n-space over Q for several types of <em>D</em>.

Let <em>X</em>(<em>K</em>) &sub; <strong>P</strong>^<em>n</em> (<em>K</em>) be a projective algebraic variety over <em>K</em>, and let <em>D</em> be a subset of <strong>P</strong>^<em>n</em>_<em>OK</em> such that the codimension of <em>D</em> with respect to <em>X</em> &sub; <strong>P</strong>^<em>n</em>_<em>OK</em> is two. We are interested in points <em>P</em> on <em>X</em>(<em>K</em>) with the property that the intersection of the closure of <em>P</em> and <em>D</em> is empty in <strong>P</strong>^<em>n</em>_<em>OK</em>, we call such points <em>D</em>-integral points on <em>X</em>(<em>K</em>). First we prove that certain algebraic varieties have infinitely many <em>D</em>-integral points. Then we find an explicit description of the complete set of all <em>D</em>-integral points in projective n-space over Q for several types of <em>D</em>.

E. Bombieri et J. Pila ont introduit une méthode qui donne les bornees sur le nombre de points entiers qui sont appartiennent d'un arc donné (sous les plusieurs hypothèses).Dans la partie algébrique nous généralisons la méthode de Bombieri Pila pour le cas des champs de fonction de genre $0$ avec une variable. Ensuite, nous appliquons le résultat pour calculer le nombre de courbes elliptiques qui sont dans la même classe d'isomorphisme avec leurs coefficients dans une petite boîte.Une fois que nous avons prouvé ça, la question naturelle est de savoir si nous pouvons l'améliorer dans certains cas particuliers. Nous allons étudier le cas des courbes elliptiques en utilisant la partie de conjecture par Birch Swinnerton-Dyer, les propriétés des fonctions de hauteur bien avec les empilements compacts.Après, dans une partie analytique nous donnons la version explicite du théorème de Bombieri Vinogradov. Ce théorème est un résultat important concerne le terme d'erreur dans le théorème de Dirichlet sur les progressions arithmétiques, pris en moyenne sur les modules $q$ variant jusqu'à $Q$. Notre but est d'améliorer les résultats existant de cette façon (voir cite{Akbary2015}), donc nous pouvons réduire la puissance du facteur logarithmique en utilisant l'inégalité de grand crible et l'identité de Vaughan. / E.Bombieri and J.Pila introduced a method to bound the number of integral points in a small given box (under some conditions). In algebraic part we generalise this method to the case of function fields of genus $0$ in ove variable. Then we apply the result to count the number of elliptic curves falling in the same isomorphic class with coefficients lying in a small box.Once we are done the natural question is how to improve this bound for some particular families of curves. We study the case of elliptic curves and use the fact that the necessary part of Birch Swinnerton-Dyer conjecture holds over function fields. We also use the properties of height functions and results about sphere packing.In analytic part we give an explicit version of Bombieri-Vinogradov theorem. This theorem is an important result that concerns the error term in Dirichlet's theorem in arithmetic progressions averaged over moduli $q$ up to $Q$. We improve the existent result of such type given in cite{Akbary2015}. We reduce the logarithmic power by using the large sieve inequality and Vaughan identity.