In the long empty query
box, enter one or more terms
(e.g., benzene) which
describe your search needs topic.�
These may be any combination of words, chemical names, and numbers,
including Chemical Abstracts Services (CAS) Registry Numbers (RN).� Common �stop words� such as �a,� �an,�
�for,� �the,� and �it,� although you may enter them, will not be searched.
Examples of search terms:
-
acetone
-
vinyl chloride
-
67-64-1
-
75-01-4
-
brain
-
dna adducts
-
skin tumors in mice
-
biomarkers
-
aflatoxin b1
The term(s) entered will be
searched for in all GENE-TOX fields.
The search will be initiated
when you click the �Search� button.� To erase your search term(s) and start over with a blank query box again, click on
the �Clear�
button.
If your query consists of
chemicals, TOXNET will, by default (i.e., the radio button �Yes� is marked selected), expand your search by adding synonyms and
CAS Registry Numbers.� Thus, if you
enter �perchloroethylene,� the system will add the CAS RN 127-18-4 and synonyms such as �tetrachloroethylene� and �tetrachloroethene.�� You have the option to turn off this feature
by marking selecting the button �No.�� This will result in a search only for the
exact word(s) you entered.� In the
example above, the system would then look only for the word
�perchloroethylene.��
For typical queries, it is
suggested that you leave the synonym searching feature on (leave �Yes� button markedselected) in order to maximize
retrieval.� On the other hand, if you were searching
specifically for a brand name product, say �tylenol,� and were interested only in records that
mentioned the chemical with that name, you might want to turn off synonym
searching (mark �No� button selected).
Clicking on the Browse the Index button willThis feature displays
a segment of the GENE-TOX index, beginning with the term you enter (e.g., hexachlorobenzene), and lets
you scan the index alphabetically (or numerically) above or below the original
display by clicking on the �UP�Up or �DOWN�Down button.� For each index term, the system displays Tthe number of GENE-TOX
records containing each of thethat terms is displayed.� By checking the �Check to Select� box(es) nextcorresponding to the index term(s) of interest and clicking on the �Check to Select�
button, you can search on these selected term(s).�
You may browse the index to all words, CAS Registry Numbers, or chemical
names.
Databases (The
Left Column of the Screen)
Clicking on any of the cells
in this column will take you directly to the search screen for the database listedselected.� �Multi-databases� offers simultaneous
searching of HSDB, CCRIS, IRIS, and GENE-TOX.�
The information icon (�i�) next to each database provides a brief
description of it, with links to a more detailed Fact Sheet and a sample
record.�
Other
NLM Resources, Support Pages (The
Right Column of the Screen)
You may also visit
additional NLM Web-Based Resources:
����������� DIRLINE � Directory andof health and scientific
organizations.
����������� Tox Web Links � Links to additonaladditional toxicology wWeb sites.
����������� MEDLINEplus Tox/Env
Health � Consumer health information on toxicology and environmental
����������� Hhealth topics.
����������� PubMed � Access to the MEDLINE database of biomedical
literature.
����������� NLM Gateway � Searches across multiple NLM databases.
����������� Locatorplus � NLM�s
online catalog of books, audiovisuals, and journals.
Or Support Pages:
����������� Help � Page specific dDetailed documentation, such as what you are now reading now, about searching
TOXNET.
����������� Fact Sheet � ForProvides an expanded description of GENE-TOX.
����������� Sample Record � A look at a sample GENE-TOX record.
�����������
Your initial retrieval is
displayed as a list of chemical names, highlighted in blue and underlined, and
their CAS Registry Numbers.� If your
search was for a chemical (e.g., benzene) and there is a match for it in the database, the
record for this chemical, referred to as the primary chemical record, will
display first, followed by a list of other chemical records which also contain
some mention of the chemical you entered.�
This latter list of chemicals is displayed according to a Relevancy
Ranking algorithm.� Clicking directly on any of
the items will provide a display of the Selected Record Screen, containing all
the data, for that item.
If your query consists of
words that are not chemical terms, this same Relevancy Ranking algorithm
determines the order of display of all your search results.
By checking one or more of
the numbered boxes to the left of eachthe list of records, you can perform later operations, such as downloading, on these selections at a later time.
You can alter your search,
if you choose, directly in the query box which reappears on this page with your
search terms.� Alternately, you can use
the Modify Search
button, described below.
The sidebar vertical series of buttons on
the left side of the Search
Results page offers a variety of options:
Save
Checked Items � This is used to create a subset of your search
results.� First check the records you
want to save, .� Tthen
click on �Save
Checked Items.��
The system confirms the number of items you saved and lets you display
just these references by clicking on a new button � Display
Saved Items � which is added to the series of buttons�.�
Sort �
Sort all or some of the records alphabetically (in ascending or descending order) by chemicalsubstance name.
Details � Summarizes the strategy used by TOXNET to perform
your search.� This will include your
query terms plus any synonyms or CAS rRegistry nNumbers added by the
system.
History �
Reviews your search session by itemizing your search statements, numbering them
sequentially, and listing the number of records retrieved.� Clicking on �History�
allows you to view earlier search result sets or combine these sets provided
they are within the same database.
Download �
You can download all or some of the records in �brief� or �full� formats and
select particular categories of information (custom formats).
Modify
Search � Return to the Basic Search Sscreen with your search
strategy retained.� You can make changes
or perform a new search at this point.
Basic
Search � Return to the Basic Search Sscreen with the searchquery box cleared.� �that yYou can now enter a new search.
Browse
Index � This
feature displays a segment of the GENE-TOX index, beginning with the term you enter, and lets you scan the
index alphabetically (or numerically) above or below the original display by
clicking on the �UP�Up or �DOWN�Down button.� For each index term, the system displays Tthe number of GENE-TOX
records containing each of thethat terms is displayed.� By checking the �Check to Select� box(es) nextcorresponding to the index term(s) of interest and clicking on the �Check to Select�
button, you can search on these selected term(s).�
You may browse the index to all words, CAS Registry Numbers, or chemical
names.
TOXNET
Home � Return to the TOXNET Home Page.
The top and bottom of each
Search Results page always displays the total number of items retrieved and the
range of items displayed on the current page, and, depending on the number of
search results, the current page number and the total number of pages. You can
navigate through multi-page search results either by specifying a page number
and pushingclicking on the �Go�
button or by using the small blue arrows to go
to the following or preceding page(s).
About
the Selected Record Screen
This screen displays the
record for whichever item you selected on the Search Results screen.� If you search for a chemical (e.g., benzene) and then click
on the �Primary Record� of the Search Results screen, you will see the entire
record, along with a Table of Contents frame on the left.� If you click on a different chemical record,
the sections of the record best matching your query terms will be displayed
(see Best Sections), again, with an accompanying Table of Contents frame.� From the Table of Contents, you can then
select to view portions of the record by expanding and contracting categories
and selecting specific categories and/or fields of the record.
If your original search was
for a term other than a chemical, any chemical record you click on from the
Search Results screen will result in a �Best Sections� display.
The search term(s) you
entered, as well as synonyms (if you selected to search for them), will all be highlighted
in red wherever they appear in the text of the selected chemical record.
Across the top of the screen
is a header
series of
buttons with more options:
Next
Item � Move
forward for a display of the next item (if there is one) in your search
retrieval or saved items set.
Previous
Item � Move
backward for a display of the previous item (if there is one) in your search
retrieval or saved items set.
Search
Results �
Return to the Search Results display.
Basic
Search �
Return to the Basic Search screen with the searchquery box cleared so that
you can enter a new search.
Details �
Displays a summary of the strategy you specified for your search and synonyms
added by the system.
Other
Files � Link
directly to records in other TOXNET data or bibliographic files (e.g., HSDB,
IRIS, TOXLINE) containing information on your selected chemical.�
Modify
Search �
Return to the Basic Search screen with your search strategy retained.� You can make changes or perform a new search
at this point.
Download �
You can download the selected record in �full� format and select a particular
category of information (custom format).
Browse
Index � This
feature allows you to display a segment of the GENE-TOX index, beginning with the term
you enter, and lets
you scan the index alphabetically (or numerically) above or below the original
display by clicking on the �UP�Up or �DOWN�Down button.� For each index term, the system displays Tthe number of GENE-TOX
records containing each of thethat terms is displayed.� By checking the �Check to Select� box(es) nextcorresponding to the index term(s) of interest and clicking on the �Check to Select�
button, you can search on these selected term(s).�
You may browse the index to all words, CAS Registry Numbers, or chemical
names.
TOXNET
Home �
Return to the TOXNET Home Page.
TOXNET searches for your
terms, in singular and plural form, throughout allthe records unless you specify
particular fields.� The system will
automatically look for synonyms and CAS Registry Numbers of chemicals unless
you choose to disable this feature.
����������� Multiple Terms
If
you search on multiple query terms, and each record retrieved
contains all the terms you entered, the system will first display those records
in which all the terms appear in the same section of the record.� This These records will be followed by records where in which the terms appear
anywhere in
different sections of the record.� If a multiple-term search fails to retrieve
any records containing all the terms entered, the system will display the
following message: �No records were found which contain all of the search
words.� The following records contain at
least one of the words.�
����������� Relevancy Ranking
Relevancy
ranking attempts to determine which documents are most pertinent to the search,
and to place the most relevant documents first in the list of returned
documents.� The ranking is based upon
the number of individual search terms occurring in a document, the number of
times each search term occurs in a document, its rarity within the database,
and the nearness of search terms to each other.� Documents containing combinations of search words tend to be ranked higher
than documents having isolated occurrences of the words.
����������� Best Sections
In
searching for a particular chemical, say �benzene,� your retrieval may include chemical records
in addition of to the initial matching chemical record,
called the �primary� record.� These other additional records might appear
if they otherwise
contain the word �benzene.��
This might occur, for example, if the chemical is a metabolite of
benzene, interacts with benzene, or has been tested along with benzene in a
toxicity study.�
Clicking
on any of these non-primary chemicals on the Search Results screen will display
the Best Sections, those where the chemical search term appears with greatest
frequency.� The term searched appears
highlighted in red.
Another
situation where in which Best Sections would occur is in
searching for a subject, say �DNA.�� In
this case, clicking on any of the chemicals in the Search Results screen will
display the Best Sections, i.e., the sections of the records where the word
�DNA� appears with the greatest frequency.�
GENE-TOX is created by the
U.S.Environmental Protection Agency (EPA) and contains genetic toxicology
(mutagenicity) test data, resulting from expert peer review of the open
scientific
literature, on over 3000
chemicals. The GENE-TOX program was established to select assay systems for
evaluation, review data in the scientific literature, and recommend proper
testing protocols and evaluation procedures for these systems.
Users seeking a finer degree
of precision in retrieval than available through TOXNET�s standard Basic Search
screen may want to consider formulating searches through the use of field
qualifiers and/or Boolean logic.
Users seeking a finer degree
of precision in retrieval than available through TOXNET�s standard relevancy
ranking methodology may want to consider formulating searches through the use
of field qualifiers and/or bBoolean logic.
Field
Qualifying is a
method whereby you can specify the particular field in which you want your term
searched.� Thus, if you are looking for
chemical records that specifically address the Ames test in the GENE-TOX
Evaluation B (post-1980) field, you might want to limit (or qualify) your
search by specifying that only that field (genb) be searched for the word
�ames.�� The format for field qualifying
consists of the search term followed by the field mnemonic in brackets.� Thus, continuing with this example, to look
for records where �ames� appears in the �genb� field, you would enter �ames
[genb].�� The field mnemonic for
chemical name is �na.�� A search for the
exact chemical name �chlorine�
in the GENE-TOX file, for example, would be formulated as �chlorine [na].�� Be advised that when you qualify a search by
data field mnemonic, you are instructing the TOXNET system to search for
precisely the field you have specified.�
If the search term does not appear in the qualified field, an error
message stating that �No records were found for the search� will be
generated.� A list of database fields
and corresponding mnemonics for GENE-TOX may be found at GENE-TOX Content
and Field Mnemonics.
Boolean Searching utilizes the logical operators OR, AND, NOT.� It is a means of limiting your search of two
or more terms to criteria you specify, and is often used in conjunction with
field qualifying, described above.�
Logical operators must appear in upper case.� Searches containing combinations of these operators are processed
with ANDs taking precedence, followed by NOTs, and then followed by ORs.� This default precedence may be overridden
with the use of parentheses, which may also be nested (i.e., parentheses within
parentheses).�
Truncation � The asterisk (*) may
be freely used as a truncation symbol standing for any number of
characters.� Searching in GENE-TOX for
mutagen* will retrieve records with words such as mutagen, mutagens, and
mutagenesis.� Truncation may be used
with or without Ffield Qqualifying/Boolean Ssearching.
Phrase Searching � In
phrase searching, Qquotations marks (���)
are included as part of
the search strategy and are used to search for two or more terms exactly
the way you
enter themthey
are entered.� A search for
�drosophila melanogaster� in the GENE-TOX Evaluation B (post-1980) field would
be phrased as follows: �drosophila melanogaster� [genb]phrased .� Phrase Ssearching may be used
with or without Ffield Qqualifying/Boolean Ssearching.
TOXNET is best viewed with
Internet Explorer 4.0 or Netscape 4.0 or higher versions, for either PC or Mac.