Linq to xml 如何在LINQ to XML中指定顶行数？

在LINQ to SQL中，我可以说var……Take50； 现在我有了以下LINQ2XML代码：

                    XElement xml = new XElement("Materials",
                    from material in _db.MTIs
                    where material.MTName.ToString().Contains(comparer)
                    select new XElement("Material",
                              new XElement("MTID", material.MTID),
                              new XElement("MTName", material.MTName),
                              new XElement("ComputerNO", material.ComputerNO),
                              new XElement("ModelNO", material.ModelNO),
                              new XElement("Whole", material.Whole)));

我只想得到前50行匹配结果，我怎么能做这样的事情

谢谢

                XElement xml = new XElement("Materials",
                _db.MTIs.Where(material => material.MTName.ToString().Contains(comparer))
                .Take(50)
                .Select(material =>
                    new XElement("Material",
                          new XElement("MTID", material.MTID),
                          new XElement("MTName", material.MTName),
                          new XElement("ComputerNO", material.ComputerNO),
                          new XElement("ModelNO", material.ModelNO),
                          new XElement("Whole", material.Whole))));