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This module is an introduction to performing searches of the NCBI databases using Entrez, the NCBI web-based search and retrieval tool for integrated search results from multiple databases.

Entrez (1) is a search and retrieval tool developed by NCBI that is capable of searching multiple NCBI databases with just one query. Entrez returns search results that can include a combination of many types of data on the query, such as nucleotide sequences, protein sequences, macromolecular structures, and related articles in the literature. Prior to the creation of Entrez, an individual might have to place one query to a nucleotide database to find a nucleotide sequence, submit another query to a structural database to find the published structure of the gene product, and submit a final query to a literature database to find citations for journal articles on the query topic. NCBI recognized the time and effort that could be saved by a tool that could cross-link these databases and integrate all information related to a given query subject into one report.View the Entrez Database page . This module contains a few problem questions, for use in a computer lab setting. The lab instructor may require that yousupply answers to these questions as an indication that you have completed the module.

The Entrez Nucleotides database includes sequences from GenBank, RefSeq, and PDB. GenBank is the National Institutes of Health (NIH) genetic sequencedatabase. GenBank, the DNA DataBank of Japan (DDBJ) and the European Molecular Biology Laboratory (EMBL) comprise the International Nucleotide SequenceDatabase Collaboration. These three organizations exchange data on a daily basis. The number of bases in the Entrez Nucleotides database currently growsat an exponential rate. Click on the Nucleotide link listed under the heading "Nucleotide Databases".

What is the number of bases stored in the Entrez nucleotide database, as of the last report?

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Use the back arrow of the browser to return to the Entrez Database web page. Locate the MMDB (Molecular Modeling DataBase), one of NCBI's structure databases and clickon the link to read about it. MMDB is a subset of three-dimensional structures obtained from the ProteinData Bank (PDB), excluding theoretical models. While the protein databases contain protein sequences, the structural database contains coordinate files (PDB files) of biological molecules with solved (known) structures.Click on the arrow next to the search box at the top of the web page and view the list of databases for selection.The literature database is accessed through PubMed, which encompasses the National Library of Medicine'sjournals database, MEDLINE, as well as providing some additional online services. MEDLINE is a collection of medical and life science journalcitations that includes articles dating back to the mid-1960's.Entrez allows access to information such as nucleotide and protein sequencesorganized by species in the NCBI taxonomy database, also found on the selection list. The connectivity of the databases available on the selection list are indicated by the diagram on the Entrez Database web page . Click on the diagram to access a Flash model of Entrez database connectivity. As long as the browser has a Flash plug-in, placing the mouse over one of the nodes representing a database will highlight its connectivity.Try this on the node labeled "Protein". Actually clicking on the node will forward the user to the database home page.

Questions & Answers

find the 15th term of the geometric sequince whose first is 18 and last term of 387
Jerwin Reply
The given of f(x=x-2. then what is the value of this f(3) 5f(x+1)
virgelyn Reply
hmm well what is the answer
how do they get the third part x = (32)5/4
kinnecy Reply
can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
okay, so you have 6 raised to the power of 2. what is that part of your answer
I don't understand what the A with approx sign and the boxed x mean
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
I'm not sure why it wrote it the other way
I got X =-6
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
oops. ignore that.
so you not have an equal sign anywhere in the original equation?
is it a question of log
Commplementary angles
Idrissa Reply
im all ears I need to learn
right! what he said ⤴⤴⤴
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Bios 533 bioinformatics. OpenStax CNX. Sep 24, 2008 Download for free at http://cnx.org/content/col10152/1.16
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