```xml
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ns4:query_definition xmlns:ns2="http://www.i2b2.org/xsd/cell/crc/psm/1.1/" xmlns:ns4="http://www.i2b2.org/xsd/cell/crc/psm/querydefinition/1.1/" xmlns:ns3="http://www.i2b2.org/xsd/cell/crc/psm/analysisdefinition/1.1/">
    <query_name>Essential (prim@15:01:19</query_name>
    <query_timing>ANY</query_timing>
    <specificity_scale>0</specificity_scale>
    <panel>
        <panel_number>1</panel_number>
        <panel_timing>ANY</panel_timing>
        <panel_accuracy_scale>100</panel_accuracy_scale>
        <invert>0</invert>
        <total_item_occurrences>1</total_item_occurrences>
        <item>
            <hlevel>3</hlevel>
            <item_name>Essential (primary) hypertension</item_name>
            <item_key>\\ICD10_ICD9\Diagnoses\(I00-I99) Dise~3w8h\(I10-I15) Hype~5igm\(I10) Essentia~sbwm\</item_key>
            <item_icon>FA</item_icon>
            <tooltip>Diagnoses \ Diseases of the circulatory system (i00-i99) \ Hypertensive diseases (i10-i15) \ Essential (primary) hypertension</tooltip>
            <class>ENC</class>
            <item_is_synonym>false</item_is_synonym>
        </item>
        <item>
            <hlevel>2</hlevel>
            <item_name>Ischemic heart diseases (i20-i25)</item_name>
            <item_key>\\ICD10_ICD9\Diagnoses\(I00-I99) Dise~3w8h\(I20-I25) Isch~798s\</item_key>
            <item_icon>FA</item_icon>
            <tooltip>Diagnoses \ Diseases of the circulatory system (i00-i99) \ Ischemic heart diseases (i20-i25)</tooltip>
            <class>ENC</class>
            <item_is_synonym>false</item_is_synonym>
        </item>
    </panel>
</ns4:query_definition>

```

I want to find patients with essential (primary) hypertension and ischemic heart diseases (i20-i25) diagnoses in the ICD10_ICD9 coding system within the Diseases of the circulatory system (i0-i9) category. The specificity scale is set to 0, indicating that any occurrence of these conditions is relevant, and the panel accuracy scale is set to 100, meaning the entire panel must be true for the patient to be included in the query results. The query timing is set to ANY, so there is no restriction on when the diagnosis was made. The panel number is 1, and the panel timing is also set to ANY, so there are no restrictions on when the conditions were diagnosed in relation to each other. The total number of items in the panel is 1, and the panel is not inverted. The class of the items is ENC (Encounter), and the items are not synonyms.