The journal that I have been reading from for my blog posts is Medical Anthropology Quarterly, which is published for the Society for Medical Anthropology by the American Anthropological Association. It addresses topics in human health and disease from an anthropological perspective. Now for the rhetorical analysis...
The structure of the material that I read in Medical Anthropology Quarterly was all scholarly journal articles that were divided into specific headings, like most other professional articles are divided. The abstract section at the beginning of each article gave a preview of what was going to be discussed in the article, but as Linton mentioned, there was never really a conclusion or explicit main idea listed in the abstract. The abstract just contained the reason that the research was being done, the main idea, and the researcher's hypothesis about the subject. The headings in the article can be somewhat confusing if you are not familiar with the layout of journal articles because they seem to list things somewhat out of order, but once you understand the flow of journal articles, they are almost easier to read and understand than regular papers.
The referencing done in the articles in Medical Anthropology Quarterly were just like those of most science type writing because the research done is all building on existing work. The journal articles were not meant to replace any previous research that was done on the subject, but to expand on the topics and note any major changes that have occurred since the last research was done. The formatting of the references are not in direct quotes like those of writing in the humanities. All of the references are integrated into the text, with only the most important parts of the information listed.
The language of the articles also has a very scientific tone. Many of the articles that I read were actually just building on previous research, and tying different areas of previous research together, not really disagreeing with previous researchers. However, the disagreement that is expressed in some of the articles is directed toward the methodologies used, not one person in particular. One convention that is used in the articles, that was mentioned by Linton is "hedging". The researchers carefully added in phrases such as "it is reasonable to conclude" and "the research suggests". These phrases convey a slight doubt or serve as a notice that their research is not a 100% fact, it is just that, research.
The epistemology of the articles has a very realist tone. The writing is not meant to be flowery or include any unnecessary details. The words are used to convey the research that was done, not be entertaining. In this way, the reader is supposed to "look through" the writing and understand the point that the writer is getting across, not analyze the way that it is written. This is why many scientific journal articles are written in the same format. People reading the article can skip to specific sections in order to read the part that they are interested and all of the information is very concise.
I think that the audience for Medical Anthropology Quarterly is mainly the medical population that is interested in anthropological research. The articles are heavy in medical jargon, and many of them reference previous studies in a way that makes it seem like you are expected to have previous knowledge of these research studies. Someone with less of a medical background would be capable of reading the journal, but it would just take longer to figure out what the article was actually trying to convey.