JOURNAL OF CLINICAL MICROBIOLOGY

Limit the abstract to 250 words or fewer and concisely summarize the basic content of the paper without presenting extensive experimental details. Avoid abbreviations and references, and do not include diagrams. When it is essential to include a reference, use the same format as shown for the References section but omit the article title. Conclude the abstract with a summary statement. Because the abstract will be published separately by abstracting services, it must be complete and understandable without reference to the text. Introduction. The introduction should supply sufficient background information to allow the reader to understand and evaluate the results of the present study without referring to previous publications on the topic. The introduction should also provide the hypothesis that was addressed or the rationale for the present study. Choose references carefully to provide the most salient background rather than an exhaustive review of the topic. Case Report. The Case Report section, placed after the introduction and before Materials and Methods, is optional and gives relevant clinical information about one or more patients while being incidental to the rest of the paper. (If the Case Report constitutes the entire article, the paper must be presented in Case Report format [see p. 12], which differs from that used for a full-length text or a Note.) Materials and Methods. The Materials and Methods section must include sufficient technical information to allow the experiments to be repeated. The sources of all media (i.e., name and location of manufacturer) or components of a new formulation must be provided. When centrifugation conditions are critical, give enough information to enable another investigator to repeat the procedure: make of centrifuge, model of rotor, temperature, time at maximum speed, and centrifugal force ( g rather than revolutions per minute). For commonly used materials and methods (e.g., media and protein concentration determinations), a simple reference or specifically recommended product or procedure is sufficient. If several alternative methods are commonly used, it is helpful to identify the method briefly as well as to cite the reference. For example, it is preferable to state ‘‘cells were broken by ultrasonic treatment as previously described (9)’’ rather than to state ‘‘cells were broken as previously described (9). ’’ This allows the reader to assess the method without constant reference to previous publications. Describe new methods completely, and give sources of unusual chemicals, reagents, equipment, or microbial strains. When large numbers of microbial strains or mutants are used in a study, include tables identifying the immediate sources (i.e., sources from whom the strains were obtained) and properties of the strains, mutants, bacteriophages, plasmids, etc. A method, strain, etc., used in only one of several experiments reported in the paper may be described in the Results section or very briefly (one or two sentences) in a table footnote or figure legend. It is expected that the sources from whom the strains were obtained will be identified. Results. In the Results section, include the rationale or design of the experiments as well as the results; reserve extensive interpretation of the results for the Discussion section. Present the results as concisely as possible in one of the following: text, table(s), or figure(s). Avoid extensive use of graphs to present data which might be more concisely presented in the text or tables. For example, except in unusual cases, doublereciprocal plots used to determine apparent Km values should not be presented as graphs; instead, the values should be stated in the text. Similarly, graphs illustrating other methods commonly used to derive kinetic or physical constants (e.g., reduced-viscosity plots and plots used to determine sedimentation velocity) need not be shown except in unusual circumstances. All tabular data must be accompanied by either standard deviation values or standard errors of the means. The number of replicate determinations (or animals) used for making such calculations must also be included. All statements concerning the significance of the differences observed should be accompanied by probability values given in parentheses. The statistical procedure used should be stated in Materials and Methods. Limit illustrations (particularly photomicrographs and electron micrographs) to those that are absolutely necessary to show the experimental findings. Number figures and tables in the order in which they are cited in the text, and be sure to cite all figures and tables. Discussion. The Discussion section should provide an interpretation of the results in relation to previously published work and to the experimental system at hand. It must not contain extensive repetition of the Results section or reiteration of the introduction. In short papers, the Results and Discussion sections may be combined. Acknowledgments. The source of any financial support received for the work being published must be indicated in the Acknowledgments section. (It will be assumed that the absence of such an acknowledgment is a statement by the authors that no support was received.) The usual format is as follows: ‘‘This work was supported by Public Health Service grant CA-01234 from the National Cancer Institute. ’’ VOL. 45, 2007 2007 JCM INSTRUCTIONS TO AUTHORS 9