Reading a scientific paper is not like reading a novel. Important aspects include reading for understanding and reading to critically evaluate the science. There are different approaches to reading a scientific paper--try different ones to see what works for you. Here are several internet resources describing different approaches to reading a scientific paper:
A reference book in the library on how to write a thesis: "How to write a successful science thesis: The concise guide for students" William E. Russey, Hans F. Ebel, Claus Bliefert. Call #LB2369 .R87 2006
Places you might search to find scientific articles:
Web of Science: A compilation of journal articles that provides broad coverage of many journals. Can be searched by author, keywords, and other features. For most searches, you may want to limit your search to Science Citation Index.
PubMed: A compilation developed by the National Institutes of Health allows you to search by keywords, authors, or other items. Most journals indexed in PubMed are biologically related. Many physics-only journals are not referenced in this database.