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  1. R

    What are these called?

    Electrically operated (either by battery or plug in), and uses vacuum to direct fluid transfer into and out of pipettes that you attach to it. I always thought they were automated pipettors but I can't find anything like what I use in the lab on the web. Any thoughts? I'm looking to purchase...
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    For those of you with the Alberts text

    For those of you with the Alberts text...... Page 999, top paragraph: "Once the pre-RC has been assembled in G1, the replication origin is ready to fire . The activation of S-Cdk in late G1 pulls the trigger and initiates DNA replcation. The initiation of replication also requires the...
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    Buffer preparation problem

    I don't know if I can effectively convey what I am doing here, but I am going to try because I need the help. I am trying to determine my ratio of acid to base and subsequently make a .5M Tris-HCl buffer utilizing Tris base, and concentrated HCl. By my calculations I get a 19.05 parts acid/1...
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    Horse hemoglobin

    I am looking for information regarding bovine or (preferrably) horse hemoglobin (human may even work). Specifically, I would like to know molecular weight, heat stability characteristics and behavior in any popular detergents (SDS would be nice). The link below was the only thing I turned up...
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    Hendersen Hasselbach

    I am starting to make the various buffers for my research, but I am a bit rusty with my chemistry. I want to know if hendersen hasselbach equation can be used if the desired pH is higher than the pKA. Specifically, I want to make 1.5 M Tris-HCl buffer (pH 8.8) utilizing Tris base and HCl. I...
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    Taxonomy question

    Is phylum=division? Thanks!
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    Enhancers and response elements

    What is the difference exactly? Thanks!
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    What does expressed at a basal level mean?

    "expressed at a basal level"; used in reference to expression of the the human metallothionein gene. Any thoughts would be most welcome. Thanks!
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    Looking for books

    Perhaps this will be of use to other people as well. I am looking for a book or books that basically consists of techniques used and currently in use in the field of biochemistry and molecular biology with an emphasis on theory and NOT protocol. I will start, as I do have one good one, but...
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    Cis and Trans Acting Elements/Sites

    I am a bit confused I guess about exactly what these are. If anyone could offer up an example of each, I would be very grateful. I did find this much: http://cancerweb.ncl.ac.uk/cgi-bin/omd?query=cis+acting [Broken]
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    More terminology

    Well Another God, it looks like you are gonna get your wish! What is a nucleosome positioning element?
  12. R

    Mobility shift assays

    I am looking for some good links on this particular methodology. Anybody have any?
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    Allergies and smoking

    I have a friend who has developed some really horrendous allergies lately, and it is my suspicion that it is because she is a heavy smoker (there is a correlation between when she started and the allergies). I can't find anything specific in my immuno textbook though. Can anyone refer me to...
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    Transcriptional start sites are called promoters

    I know that transcriptional start sites are called promoters. My professor made reference to a "core promoter" on a day that I missed class (looking at notes from that day). I am not familiar with this terminology, can anyone help me out here?
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    Neat website

    http://www.hgmp.mrc.ac.uk/GenomeWeb/ [Broken]
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    Genetics Terminology Question

    Sadly enough, I have never seen a delta symbol in front of a printed genotype. Does this mean anymore than the obvious (obvious being some given changed, unstated, to the genotype)?
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    PpGpp and cellular processes

    I am interested in knowing if ppGpp plays a role, direct or indirect, in inhibition of DNA replication and transcription in prokaryotic cells. I can't find anything direct, but it would be my guess that in times of amino acid starvation, the cell won't actively divide, or transcribe any RNA.
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    Polymyxin and LPS

    Does anyone know the exact mechanism by which polymyxin arrives at the outer cell membrane after binding to LPS? The best source I have states that "it first binds to the outer membrane of E. coli or Salmonella typhimurium, presumably by binding to LPS, and then goes through the outer membrane...
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    New classes of antibiotics

    I am being asked to discuss antibiotic resistance for a take-home exam and I was wondering if I am missing any classes of antibiotics. This is what I have: *Sulfonamides *Quinolones *Penicillins *Cephalosporins *Tetracyclines *Aminoglycosides *Macrolides *Chloramphenicol *The book...
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    Snell's law of refraction problem

    Hello everyone, I am reviewing for a test tomorrow, and I seem to have come across what would seem like an easy problem, but its answer has eluded me for the time being. I am hoping you guys can help. Horizontal rays of red light (660nm in a vacuum) and violet light (410nm in a vacuum)...
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    Converging and diverging lenses

    Hello, I am reading over the topic of converging and diverging lenses, and I had a question relating to phenomena of image formation as seen through these. Based on the ray diagrams that are typically used (freshman physics) how does one conclude whehter or not an image is inverted or...
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    Klenow Fragment

    I know what it is, but my question is: What are some (specifically) popular applications? I am guessing some sort of specialized PCR??? Any thoughts would be appreciated.
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    Ligate a gene fragment

    I will be attempting to ligate a gene fragment (~650bp's) into a Pbluescript plasmid here in the next day or so. The fragment and the vector have both already been digested and purified, so that's not an issue. However, I have been advised by a number of differnt people that the concentrations...
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    How soon does DNA settle?

    I ran a PCR last week but did not get around to running the AGE until this week, so the PCR product sat for a roughly a week at -4*C. What are the odds that all my DNA is at the bottom or stuck to the sides? A friend of mine just suggested this to me, or I would have vortexed it before running...
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    New to this forum have a question

    Hello everyone, As you can probably tell, I am new to this forum. I have been following some threads for quite some time and I have to say I am quite impressed!!! Anyway, I DID have a question amongst all this fluff. I am attempting to read a paper that was submitted and published back in...
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