UMLS CONCORDANCE FOR PATHOLOGY TEXT.

John H. Sinard, MD, PhD [1].
Gladys L. G. Alonsozana, MD [2,3]
Grover M. Hutchins, MD [4].
G. William Moore, MD, PhD [2,3,4].

From: Departments of Pathology, Yale University School of Medicine, New Haven, CT [1];
Baltimore VA Medical Center, Baltimore, MD [2],
University of Maryland School of Medicine, Baltimore, MD [3],
and The Johns Hopkins Medical Institutions, Baltimore, MD [4].

U. S. Government Work, published in:
the Johns Hopkins Autopsy Resource,
www.netautopsy.org



TABLE OF CONTENTS.


1. INTRODUCTION.
2. DESIGN.
3. UNIFIED MEDICAL LANGUAGE SYSTEM.
4. REDUNDANT INDEXING OF SUBCONCEPTS.
5. BARRIER WORD METHOD.
6. BARRIER WORD METHOD: PATHOLOGY TEXT.
7. BARRIER WORD METHOD: EMBRYOLOGY TEXT.
8. AMBIGUITIES IN UMLS.
9. GENERAL PATHOLOGY RESULTS.
10. EMBRYOLOGY RESULTS.
11. DISCUSSION.
12. FUTURE DIRECTIONS: SYNONYMS FOR UMLS.
13. REFERENCES.
14. ZIPF DISTRIBUTION OF PATHOLOGY CUIS.
15. ZIPF DISTRIBUTION OF UNMATCHED PATHOLOGY WORDS.
16. ZIPF DISTRIBUTION OF PATHOLOGY COLLOCATIONS.
14. ZIPF DISTRIBUTION OF EMBRYOLOGY CUIS.
15. ZIPF DISTRIBUTION OF UNMATCHED EMBRYOLOGY WORDS.
19. ZIPF DISTRIBUTION OF EMBRYOLOGY COLLOCATIONS.


1. INTRODUCTION.


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  • UNIFIED MEDICAL LANGUAGE SYSTEM METATHESAURUS (UMLS-M) OF THE U. S. NATIONAL LIBRARY OF MEDICINE (USNLM).

  • MOST COMPREHENSIVE, PUBLICLY-AVAILABLE LIST OF STANDARDIZED MEDICAL TERMINOLOGY IN THE WORLD.

  • WHAT IS THE CONCORDANCE RATE FOR GENERAL PATHOLOGY AND EMBRYOLOGY TEXT?



  • 2. DESIGN.


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  • SINARD'S OUTLINES IN PATHOLOGY. 25 CHAPTERS, POPULAR REVIEW TEXT FOR PATHOLOGY BOARDS.

  • STREETER'S DEVELOPMENTAL HORIZONS IN HUMAN EMBRYOS AND RELATED REFERENCES.

  • ALL MAJOR AREAS OF ANATOMIC PATHOLOGY ARE COVERED.

  • COMPUTER-ENCODED INTO UMLS, WITH ENRICHED SYNONYM LIST.

  • CONCORDANCE: MEDICALLY-SIGNIFICANT TERM, PRESENT IN THE TEXTBOOK, AND ALSO CAPTURED BY ENCODING PROGRAM.

  • FALSE NEGATIVE: UMLS CONCEPT NOT PRESENT.

  • AMBIGUOUS TERMS AND COMPOUND TERMS CONTAINING SUBCONCEPTS INDEXED REDUNDANTLY.



  • 3. UNIFIED MEDICAL LANGUAGE SYSTEM (UMLS).


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  • UNIFIED MEDICAL LANGUAGE SYSTEM (UMLS) : DEVELOPED BY U.S. NATIONAL LIBRARY OF MEDICINE (USNLM) IN 1986.

  • PURPOSE: AID DEVELOPMENT OF SYSTEMS TO RETRIEVE ELECTRONIC BIOMEDICAL INFORMATION.

  • http://www.nlm.nih.gov/research/umls/

  • LAST UPDATED: January 1, 2000.

  • METATHESAURUS SIZE: 113,699,627 BYTES.

  • CONCEPT UNIQUE IDENTIFIERS (CUIs): 729,248, MAX=C0813178, RETIRED=83,930.

  • SYNONYMS: 1,598,176

  • OVER 50 SOURCE-VOCABULARIES.

  • OVER 20 PARTIAL TRANSLATIONS INTO FOREIGN LANGUAGES.



  • 4. REDUNDANT INDEXING OF SUBCONCEPTS.


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    CELLULAR BLUE NEVUS REDUNDANTLY INDEXED AS:


  • CELLULAR BLUE NEVUS (C0334448).

  • BLUE NEVUS (C0206736).

  • CELL (C0007634).

  • BLUE (C0332584).

  • NEVUS (C0027960).



  • 5. BARRIER WORD METHOD.


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  • NATURAL-LANGUAGE MEDICAL TEXT: SEQUENCE OF MEDICAL CONCEPTS SEPARATED BY GRAMMATICAL OBJECTS.

  • THE GRAMMATICAL OBJECTS, OR BARRIER WORDS: NUMERALS, PUNCTUATION, SINGLE LETTERS, ARTICLES, PREPOSITIONS, AND COMMON VERBS AND MODIFIERS.

  • MEDICAL CONCEPTS, OR KEYWORDS: ARE ONE-WORD OR MULTIPLE-WORD TERMS CONSISTING OF MEDICALLY SIGNIFICANT WORDS.



  • 6. BARRIER WORD METHOD: SAMPLE PATHOLOGY TEXT.


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    LICHEN SIMPLEX CHRONICUS . CHRONIC FORM of any of above with IRRITATION and TRAUMA . EPIDERMIS undergoes a PSORIASIFORM THICKENING but with an increased THICKNESS of the GRANULAR LAYER . SCARRING and BROADENING of DERMAL PAPILLAE .


  • barrier words in lower case.

  • KEYWORDS IN UPPER CASE.


  •                   TEXT NAME            UMLS CUI
       LICHEN SIMPLEX CHRONICUS            C0149922
                   CHRONIC FORM   C0205179 C0376315
                             of            C0456627
                            any            C0205392*
                             of            C0456627
                          above            C0205103
                           with            C0332287
                     IRRITATION            C0441718
                            and            C0332287*
                         TRAUMA            C0548346
                      EPIDERMIS            C0014518
                      undergoes
                              a            C0205447*
        PSORIASIFORM THICKENING  C0033860* C0332527
                            but            C0332287*
                           with            C0332287
                             an            C0205447*
                      increased            C0205216
                      thickness            C2005400
                             of            C0456627
                            the            C0205435*
                 GRANULAR LAYER   C0205247 C0205274*
                       SCARRING            C0036287
                            and            C0332287*
                     broadening            C0332464*
                             of            C0456627
                DERMAL PAPILLAE   C0221927 C0205312*
    





    7. BARRIER WORD METHOD: SAMPLE EMBRYOLOGY TEXT.


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    GUT TRACT and its DERIVATIVES . at this same time the PHARYNGEAL POUCHES , which heretofore have been relatively simple LATERAL EXPANSIONS of GUT EPITHELIUM intervening between the AORTIC ARCHES , are taking the form of SPECIALIZED STRUCTURES . one can RECOGNIZE the beginning TRANSFORMATION into an AUDITORY TUBE and TYMPANUM , also the PRIMORDIA of the THYMUS , LATERAL THYROID , and SUPERIOR and INFERIOR PARATHYROID GLANDS.


  • barrier words in lower case.

  • KEYWORDS IN UPPER CASE.


  •                TEXT NAME             UMLS CUI
                   GUT TRACT    C0699818 C0332208*
                         and             C0332287*
                         its             C0027344*
                 DERIVATIVES             C0243070
                          at             C0332285*
                        this             C0205435*
                        same             C0445243
                        time             C0040213
                         the             C0205435*
          PHARYNGEAL POUCHES             C0231067*
                       which             C0043237*
                  heretofore             C0332152*
                        have             C0605770*
                        been             C0392148*
                  relatively             C0205345*
                      simple             C0205347
          LATERAL EXPANSIONS    C0205091 C0205229*
                          of             C0456627
              GUT EPITHELIUM    C0699818 C0014603
                 intervening             C0205102
                     between             C0205102
                         the             C0205435*
               AORTIC ARCHES             C0442005
                         are             C0392148*
                      taking      
                         the             C0205435*
                        form             C0376315
                          of             C0456627
      SPECIALIZED STRUCTURES    C0205548 C0678594*
                         one             C0205429
                         can             C0808716
                   RECOGNIZE             C0524637*
                         the             C0205435*
                   beginning             C0439657
              TRANSFORMATION             C0040682
                        into             C0332285
                          an             C0205447*
               AUDITORY TUBE    C0439822 C0175730
                         and             C0332287*
                    TYMPANUM             C0242251
                        also             C0332287*
                         the             C0205435*
                   PRIMORDIA             C0678727*
                          of             C0456627
                         the             C0205435*
                      THYMUS             C0496916
             LATERAL THYROID    C0205091 C0795756
                         and             C0332287*
                    SUPERIOR             C0205103
                         and             C0332287*
     INFERIOR PARATHYROID GLANDS C0678975 C0030518 C0225352
    






    8. AMBIGUITIES IN UMLS.


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  • ADNEXA WITHOUT NEARBY DISAMBIGUATING WORD:


  • SKIN ADNEXA (C0221943)

  • UTERINE ADNEXA (C0001575)

  • OCULAR ADNEXA (C0229243)



  • 9. GENERAL PATHOLOGY RESULTS.


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  • PATHOLOGY INPUT TEXT: 951 KB, 25 CHAPTERS.

  • 120,677 WORDS, 11,240 DISTINCT WORDS,

  • AVERAGE: 10.7 = 120,677/11,240 OCCURRENCES PER WORD.

  • 77,498 (64.2%) EXACT MATCHES TO A UMLS SYNONYM,

  • 33,348 (27.6%) ADDITIONAL, APPROXIMATE MATCHES TO UMLS CUIS,

  • 8.1% UNMATCHED CONCEPTS.



  • 10. EMBRYOLOGY RESULTS.


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  • INPUT TEXT: 1.26 MB.

  • 110,314 WORDS, 9,087 DISTINCT WORDS.

  • 5,323 (4.8%) MISSPELLINGS (OPTICAL MISTRANSLATIONS).

  • AVERAGE: 12.1 = 110,314/9,087 OCCURRENCES PER WORD.

  • AMONG CORRECTLY SPELLED WORDS: 48,758 (46.4%) EXACT MATCHES TO A UMLS SYNONYM;

  • 46,250 (44.0%) ADDITIONAL, APPROXIMATE MATCHES TO UMLS CUIS.

  • 9.5% UNMATCHED CONCEPTS.



  • 11. DISCUSSION.


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  • CONCORDANCE RATE: 90.9%.

  • UNMATCHED CONCEPTS TENDED TO BE DESCRIPTIVE TERMS IN PATHOLOGY THAT CHARACTERIZE MICROSCOPIC FINDINGS.

  • UMLS IS A HIGHLY INCLUSIVE CONCEPT SYSTEM FOR PATHOLOGY.

  • HOWEVER, UMLS IS SYNONYM-POOR.

  • MANY SYNONYMS MUST BE ADDED MANUALLY.

  • UMLS: NEARLY-COMPREHENSIVE METATHESAURUS FOR PATHOLOGY TEXT.



  • 12. FUTURE DIRECTIONS:
    SOURCES FOR SYNONYMS.


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  • LEXICAL VARIANTS: NUCLEI ==> CELL NUCLEUS.

  • OBVIOUS SYNONYMS: CLUSTER ==> AGGREGATE.

  • OBVIOUS MISSPELLINGS: WILM'S ==> WILMS'.
    BRONCHITS ==> BRONCHITIS.

  • OBVIOUS CONTRACTIONS: ADDISON ==> ADDISON'S DISEASE.
    CUSHING ==> CUSHING'S DISEASE.
    SQUAMOUS ==> SQUAMOUS CELL.

  • COMPOUNDS: WITHOUT ==> NEGATIVE-WITH.



  • 13. REFERENCES.


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  • 1. UMLS Knowledge Sources. 11th edition. 2000. Documentation. National Institutes of Health. National Library of Medicine. Bethesda, Maryland 20854.

  • 2. College of American Pathologists. Systematized Nomenclature of Human and Veterinary Medicine (SNOMED International). College of American Pathologists, Northfield, IL, 1993.

  • 3. Moore GW, Berman JJ, Hanzlick RL, Buchino JJ, Hutchins GM.
    A prototype Internet autopsy database. 1625 consecutive fetal and neonatal autopsy facesheets spanning 20 years.
    Arch Pathol Lab Med. 1996 Aug;120(8):782-785.

  • 4. Moore GW, Miller RE, Hutchins GM. Indexing by MeSH titles of natural language pathology phrases identified on first encounter using the barrier word method.
    In: Scherrer JR, Côté RA, Mandil SH, eds. Computerized Natural Medical Language Processing for Knowledge Representation. Amsterdam: North-Holland; pp 29-39, 1989.

  • 5. Sinard JH.
    Outlines in Pathology.
    Philadelphia: WB Saunders. 1996.

  • 6. Streeter GL
    Developmental Horizons in Human Embryology.


  • 7. O'Rahilly R.
    Human Embryos, Stages 1-8.


  • 8. Corner GW, Heuser C.
    Human Embryos, Stages 9.





    14. ZIPF DISTRIBUTION OF PATHOLOGY CUIS.


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       RANK  FREQUENCY                WORD       UMLS CUI 
          1      3,950                  of       C0456627
          2      2,591                  in       C0439203
          3      2,387                 and       C0332287*
          4      1,873                with       C0332287
          5      1,779                  to       C0332285*
          6      1,562                 the       C0205435*
          7      1,297                  or       C0332270*
          8      1,256               cells       C0007625
          9        904             usually       C0332183*
         10        899                cell       C0007634
         11        847                 may       C0806904
         12        711                  be       C0014121
         13        682                  by       C0336807
         14        681                most       C0205381
         15        604                 are       C0392148*
         16        537              common       C0205213
         17        521                  is       C0441912
         18        469               often       C0332181
         19        446                 can       C0808716
         20        439               tumor       C0027651
         21        435                 for       C0521117
         22        433               small       C0700320
         23        418                from       C0332285*
         24        406             disease       C0012633
         25        384                 but       C0332287*
         26        383           carcinoma       C0007095
         27        369                 not       C0205160*
         28        364                more       C0205171
         29        358                seen       C0205395
         30        344              tumors       C0027651
         31        334               large       C0549176
         32        333                type       C0332307
         33        322                 aka       C0332287*
         34        321                have       C0605770*
         35        307                  at       C0332285*
         36        298                  on       C0332285* 
         37        294                  as       C0003818
         38        269               which       C0043237*
         39        267                  no       C0205160*
         40        263              tissue       C0040300
         41        254            patients       C0030704
         42        248           malignant       C0205282
         43        245             present       C0392743
         44        242          associated       C0004083*
         45        240                also       C0332287*
         46        236             chronic       C0205179
         47        234                 all       C0444867
         48        232             lesions       C0221198
         49        226           prognosis       C0220901
         50        222                 age       C0001774
    




    15. ZIPF DISTRIBUTION
    OF UNMATCHED PATHOLOGY WORDS.


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       RANK  FREQUENCY                WORD
          1         48                cord      
          2         33               still      
          3         30          eventually      
          4         30                need      
          5         28               cords      
          6         27          palisading      
          7         27        particularly      
          8         26                must      
          9         25               plump      
         10         24           polygonal      
         11         24           represent      
         12         24             sharply      
         13         23         counterpart      
         14         23                germ      
         15         23                host      
         16         22       immunoblastic      
         17         22              remain      
         18         22              should      
         19         22             undergo      
         20         21              mantle      
         21         21          parenchyma      
         22         19                just      
         23         19               prone      
         24         19             unclear      
         25         18               villi      
         26         17      subendothelial      
         27         16               amino      
         28         16            arranged      
         29         16          background      
         30         16           excellent      
         31         16        intrahepatic      
         32         16         odontogenic      
         33         15              excess      
         34         15               glans      
         35         15              goblet      
         36         15                half      
         37         15           untreated      
         38         15             villous      
         39         14         independent      
         40         14               laden      
         41         14             outflow      
         42         14            subtypes      
         43         13             bundles      
         44         13              entity      
         45         13        extrahepatic      
         46         13      granulomatosis      
         47         13    intracytoplasmic      
         48         13          invariably      
         49         13           oncocytic      
         50         13          perineural      
    




    16. ZIPF DISTRIBUTION OF PATHOLOGY COLLOCATIONS.


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       RANK  FREQUENCY                   TERM     UMLS CUI 
          1        479                 of the     C0332285*
          2        244                 in the     C0332285*
          3        196        associated with     C0332281
          4        101                 due to     C0678226
          5         86            giant cells     C0017526
          6         82           plasma cells     C0032112
          7         78          smooth muscle     C0026843
          8         54            tumor cells     C0431085
          9         50                 type i     C0441729
         10         49     autosomal dominant     C0443147
         11         49             clear cell     C0229473
         12         49    well differentiated     C0205615
         13         44               into the     C0332285*
         14         44                type ii     C0441730
         15         41            soft tissue     C0225317
         16         39               gi tract     C0017189
         17         38       germinal centers     C0282491
         18         38              low grade     C0205080
         19         37             absence of     C0332197
         20         37    autosomal recessive     C0441748
         21         35      connective tissue     C0009780
         22         35    squamous metaplasia     C0025570
         23         34           spindle cell     C0682540
         24         34          squamous cell     C0221910
         25         33             bile ducts     C0005400
         26         33             within the     C0332285*
         27         32   chronic inflammation     C0021376
         28         32               from the     C0332285*
         29         31                foci of     C0205234
         30         31         poor prognosis     C0278252
         31         31            rather than     C0489693*
         32         31           well defined     C0442825
         33         30 differential diagnosis     C0220820
         34         30             giant cell     C0017526
         35         28      basement membrane     C0004799
         36         28         good prognosis     C0278250
         37         28             high grade     C0205082
         38         28          renal failure     C0035078
         39         27            bone marrow     C0005953
         40         27                in situ     C0444498
         41         26              bile duct     C0005400
         42         26            lymph nodes     C0154054
         43         26squamous cell carcinoma     C0007137
         44         25   rheumatoid arthritis     C0003873
         45         24              cell type     C0449475
         46         24           soft tissues     C0225317
         47         23               but also     C0332287*
         48         22          blood vessels     C0005847
         49         22     inflammatory cells     C0440752
         50         22               of these     C0332285*
    






    17. ZIPF DISTRIBUTION OF EMBRYOLOGY CUIS.


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       RANK  FREQUENCY                WORD        UMLS CUI 
          1     10,394                 the        C0205435*
          2      5,441                  of        C0456627
          3      3,574                  in        C0439203
          4      3,123                 and        C0332287*
          5      1,982                  to        C0332285*
          6      1,947                  is        C0441912
          7      1,042                that        C0205435*
          8        959                 are        C0392148*
          9        947                  by        C0336807
         10        919                  as        C0003818
         11        919                  be        C0014121
         12        903                  it        C0027361*
         13        756                this        C0205435*
         14        695                from        C0332285*
         15        602               which        C0043237*
         16        597                  mm        C0439266
         17        560                with        C0332287
         18        545                  at        C0332285*
         19        541             embryos        C0013935
         20        534               cells        C0007625
         21        533                  no        C0205160*
         22        515                 age        C0001774
         23        505              embryo        C0013932
         24        438               group        C0441832
         25        422               stage        C0684248
         26        417                 one        C0205429
         27        404                  an        C0205447*
         28        403                 for        C0521117
         29        389                 its        C0027344*
         30        388                  or        C0332270*
         31        372                 has        C0605674
         32        348                  on        C0332285*
         33        339                 not        C0205160*
         34        330                been        C0392148*
         35        302               these        C0205392*
         36        296                form        C0376315
         37        295                more        C0205171
         38        294                 can        C0808716
         39        294                 fig        C0349932
         40        288               human        C0020102
         41        287                have        C0605770*
         42        269           embryonic        C0521444
         43        269               plate        C0005971
         44        268           specimens        C0370003*
         45        247              figure        C0441469*
         46        240                into        C0332285
         47        238               their        C0027361*
         48        234                 was        C0392148*
         49        233           primitive        C0033153*
         50        230               shown        C0332265*
    




    18. ZIPF DISTRIBUTION OF UNMATCHED EMBRYOLOGY WORDS.


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       RANK  FREQUENCY                WORD
          1        101               stalk      
          2         52                 way      
          3         48                anat      
          4         48                germ      
          5         46                 pit      
          6         44                wash      
          7         43          prechordal      
          8         43               until      
          9         42               could      
         10         42               pairs      
         11         39               order      
         12         37            presumed      
         13         36                ones      
         14         36               taken      
         15         35                bars      
         16         34                cord      
         17         33             profile      
         18         32                come      
         19         32               shell      
         20         31                free      
         21         30             chordal      
         22         30             example      
         23         29             details      
         24         29             passage      
         25         29               polar      
         26         28           neuropore      
         27         28             sharply      
         28         27            consists      
         29         27                 how      
         30         27       intercellular      
         31         27             lacunae      
         32         27               takes      
         33         27               tubal      
         34         26            epiblast      
         35         26             instead      
         36         25              detail      
         37         25               folds      
         38         25                just      
         39         25                meso      
         40         25              partly      
         41         24          gelatinous      
         42         24              manner      
         43         24               owing      
         44         23               cited      
         45         23         conspicuous      
         46         23               quite      
         47         22               field      
         48         22          particular      
         49         22        particularly      
         50         22              proper      
    




    19. ZIPF DISTRIBUTION OF EMBRYOLOGY COLLOCATIONS.


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       RANK  FREQUENCY                   TERM       UMLS CUI 
          1      2,613                 of the       C0332285*
          2      1,037                 in the       C0332285*
          3        346               from the       C0332285*
          4        267              age group       C0596048
          5        147               has been       C0392148*
          6        141                of this       C0332285*
          7        127                for the       C0521125*
          8        123               yolk sac       C0042893
          9        110         embryonic disc       C0231003
         10        100       primitive streak       C0033153
         11         93               into the       C0332285*
         12         78              have been       C0392148*
         13         78               there is       C0332287*
         14         69            through the       C0332273*
         15         59       chorionic cavity       C0230966
         16         58            between the       C0205103*
         17         55               of these       C0332285*
         18         49              there are       C0332287*
         19         47             age groups       C0027362
         20         38         nervous system       C0027763
         21         36            neural tube       C0231024
         22         33          sinus venosus       C0231084
         23         32              the other       C0205394*
         24         30 central nervous system       C0007679
         25         29        chorionic villi       C0008508
         26         29             within the       C0332285*
         27         28          blood vessels       C0005847
         28         27                stage 5       C0441777
         29         27         zona pellucida       C0043519
         30         26            referred to       C0205543
         31         24            in addition       C0332287*
         32         24               over the       C0205136*
         33         22       cloacal membrane       C0231056
         34         22        vascular system       C0489903
         35         20              along the       C0205428*
         36         19                 due to       C0678226
         37         19         in addition to       C0332287
         38         18                site of       C0449643
         39         18                stage 2       C0441767
         40         18                stage 3       C0441771
         41         17              about the       C0475806*
         42         17              under the       C0542339*
         43         16        amniotic cavity       C0230976
         44         16             as well as       C0332287*
         45         16            rather than       C0489693*
         46         15            blood cells       C0005773
         47         14           chick embryo       C0008046
         48         14             germ cells       C0017471
         49         14               in vitro       C0021135
         50         14                of that       C0332285*
    


    Last Revised: 10/22/2000 by G. William Moore.