{"id":"https://openalex.org/W2037679686","doi":"https://doi.org/10.1016/0020-7292(90)90516-n","title":"The relationship between beta\u2010endorphin levels and uterine muscle contractions during labor","display_name":"The relationship between beta\u2010endorphin levels and uterine muscle contractions during labor","publication_year":1990,"publication_date":"1990-12-01","ids":{"openalex":"https://openalex.org/W2037679686","doi":"https://doi.org/10.1016/0020-7292(90)90516-n","mag":"2037679686","pmid":"https://pubmed.ncbi.nlm.nih.gov/1979284"},"language":"en","primary_location":{"id":"doi:10.1016/0020-7292(90)90516-n","doi":"https://doi.org/10.1016/0020-7292(90)90516-n","is_oa":false,"landing_page_url":"https://doi.org/10.1016/0020-7292(90)90516-n","pdf_url":null,"source":{"id":"https://openalex.org/S4210216427","display_name":"International Journal of Gynecology & Obstetrics","issn_l":"0020-6695","issn":["0020-6695","0020-7292","1879-3479"],"is_oa":false,"is_in_doaj":false,"is_core":true,"listed_in":["cwts-core","dongbi-c","doyens","jufo-1","ki-jl-1","medline","norway-1","poland-70","russia-white-list-1","vabb-shw"],"host_organization":"https://openalex.org/P4310320990","host_organization_name":"Elsevier BV","host_organization_lineage":["https://openalex.org/P4310320990"],"host_organization_lineage_names":["Elsevier BV"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"International Journal of Gynecology & Obstetrics","raw_type":"journal-article"},"volume":null,"type":"article","indexed_in":["crossref","pubmed"],"open_access":{"is_oa":false,"oa_status":"closed","oa_url":null,"any_repository_has_fulltext":false},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5060813627","display_name":"Nery Weissberg","orcid":null,"observed_orcids":[]},"institutions":[{"id":"https://openalex.org/I2801962034","display_name":"Shaare Zedek Medical Center","ror":"https://ror.org/04d0szq68","country_code":"IL","type":"healthcare","lineage":["https://openalex.org/I2801962034"]},{"id":"https://openalex.org/I2802879425","display_name":"Bikur Cholim Hospital","ror":"https://ror.org/03zpnb459","country_code":"IL","type":"healthcare","lineage":["https://openalex.org/I2802879425"]}],"countries":["IL"],"is_corresponding":false,"raw_author_name":"N. Weissberg","raw_affiliation_strings":["Department of Internal Medicine, Shaare Zedek Medical Center, Jerusalem, Israel"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Department of Internal Medicine, Shaare Zedek Medical Center, Jerusalem, Israel","institution_ids":["https://openalex.org/I2801962034","https://openalex.org/I2802879425"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5112192878","display_name":"N. Algur","orcid":null,"observed_orcids":[]},"institutions":[{"id":"https://openalex.org/I2801962034","display_name":"Shaare Zedek Medical Center","ror":"https://ror.org/04d0szq68","country_code":"IL","type":"healthcare","lineage":["https://openalex.org/I2801962034"]},{"id":"https://openalex.org/I2802879425","display_name":"Bikur Cholim Hospital","ror":"https://ror.org/03zpnb459","country_code":"IL","type":"healthcare","lineage":["https://openalex.org/I2802879425"]}],"countries":["IL"],"is_corresponding":false,"raw_author_name":"N. Algur","raw_affiliation_strings":["Department of Clinical Biochemistry, Shaare Zedek Medical Center, Jerusalem, Israel"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Department of Clinical Biochemistry, Shaare Zedek Medical Center, Jerusalem, Israel","institution_ids":["https://openalex.org/I2801962034","https://openalex.org/I2802879425"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5040617905","display_name":"G Schwartz","orcid":null,"observed_orcids":[]},"institutions":[{"id":"https://openalex.org/I2801962034","display_name":"Shaare Zedek Medical Center","ror":"https://ror.org/04d0szq68","country_code":"IL","type":"healthcare","lineage":["https://openalex.org/I2801962034"]},{"id":"https://openalex.org/I2802879425","display_name":"Bikur Cholim Hospital","ror":"https://ror.org/03zpnb459","country_code":"IL","type":"healthcare","lineage":["https://openalex.org/I2802879425"]}],"countries":["IL"],"is_corresponding":false,"raw_author_name":"G. Schwartz","raw_affiliation_strings":["Department of Internal Medicine, Shaare Zedek Medical Center, Jerusalem, Israel"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Department of Internal Medicine, Shaare Zedek Medical Center, Jerusalem, Israel","institution_ids":["https://openalex.org/I2801962034","https://openalex.org/I2802879425"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5113558606","display_name":"Ovadia Shemesh","orcid":null,"observed_orcids":[]},"institutions":[{"id":"https://openalex.org/I2801962034","display_name":"Shaare Zedek Medical Center","ror":"https://ror.org/04d0szq68","country_code":"IL","type":"healthcare","lineage":["https://openalex.org/I2801962034"]},{"id":"https://openalex.org/I2802879425","display_name":"Bikur Cholim Hospital","ror":"https://ror.org/03zpnb459","country_code":"IL","type":"healthcare","lineage":["https://openalex.org/I2802879425"]}],"countries":["IL"],"is_corresponding":false,"raw_author_name":"O. Shemesh","raw_affiliation_strings":["Department of Internal Medicine, Shaare Zedek Medical Center, Jerusalem, Israel"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Department of Internal Medicine, Shaare Zedek Medical Center, Jerusalem, Israel","institution_ids":["https://openalex.org/I2801962034","https://openalex.org/I2802879425"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5066962947","display_name":"Uri Eylath","orcid":null,"observed_orcids":[]},"institutions":[{"id":"https://openalex.org/I2801962034","display_name":"Shaare Zedek Medical Center","ror":"https://ror.org/04d0szq68","country_code":"IL","type":"healthcare","lineage":["https://openalex.org/I2801962034"]},{"id":"https://openalex.org/I2802879425","display_name":"Bikur Cholim Hospital","ror":"https://ror.org/03zpnb459","country_code":"IL","type":"healthcare","lineage":["https://openalex.org/I2802879425"]}],"countries":["IL"],"is_corresponding":false,"raw_author_name":"U. Eylath","raw_affiliation_strings":["Department of Clinical Biochemistry, Shaare Zedek Medical Center, Jerusalem, Israel"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Department of Clinical Biochemistry, Shaare Zedek Medical Center, Jerusalem, Israel","institution_ids":["https://openalex.org/I2801962034","https://openalex.org/I2802879425"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5110500838","display_name":"A. S. Abraham","orcid":null,"observed_orcids":[]},"institutions":[{"id":"https://openalex.org/I2801962034","display_name":"Shaare Zedek Medical Center","ror":"https://ror.org/04d0szq68","country_code":"IL","type":"healthcare","lineage":["https://openalex.org/I2801962034"]},{"id":"https://openalex.org/I2802879425","display_name":"Bikur Cholim Hospital","ror":"https://ror.org/03zpnb459","country_code":"IL","type":"healthcare","lineage":["https://openalex.org/I2802879425"]}],"countries":["IL"],"is_corresponding":true,"raw_author_name":"A.S. Abraham","raw_affiliation_strings":["Department of Internal Medicine, Shaare Zedek Medical Center, Jerusalem, Israel"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Department of Internal Medicine, Shaare Zedek Medical Center, Jerusalem, Israel","institution_ids":["https://openalex.org/I2801962034","https://openalex.org/I2802879425"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":2,"corresponding_author_ids":["https://openalex.org/A5110500838"],"corresponding_institution_ids":["https://openalex.org/I2801962034","https://openalex.org/I2802879425"],"apc_list":{"value":4480,"currency":"USD","value_usd":4480},"apc_paid":null,"fwci":0.0,"has_fulltext":false,"cited_by_count":5,"citation_normalized_percentile":{"value":0.09332464,"is_in_top_1_percent":false,"is_in_top_10_percent":false},"cited_by_percentile_year":{"min":89,"max":95},"biblio":{"volume":"33","issue":"4","first_page":"313","last_page":"316"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T10814","display_name":"Neuropeptides and Animal Physiology","score":0.5009999871253967,"subfield":{"id":"https://openalex.org/subfields/2804","display_name":"Cellular and Molecular Neuroscience"},"field":{"id":"https://openalex.org/fields/28","display_name":"Neuroscience"},"domain":{"id":"https://openalex.org/domains/1","display_name":"Life Sciences"}},"topics":[{"id":"https://openalex.org/T10814","display_name":"Neuropeptides and Animal Physiology","score":0.5009999871253967,"subfield":{"id":"https://openalex.org/subfields/2804","display_name":"Cellular and Molecular Neuroscience"},"field":{"id":"https://openalex.org/fields/28","display_name":"Neuroscience"},"domain":{"id":"https://openalex.org/domains/1","display_name":"Life Sciences"}},{"id":"https://openalex.org/T10453","display_name":"Maternal and Perinatal Health Interventions","score":0.3662000000476837,"subfield":{"id":"https://openalex.org/subfields/2729","display_name":"Obstetrics and Gynecology"},"field":{"id":"https://openalex.org/fields/27","display_name":"Medicine"},"domain":{"id":"https://openalex.org/domains/4","display_name":"Health Sciences"}},{"id":"https://openalex.org/T12715","display_name":"Pregnancy-related medical research","score":0.03629999980330467,"subfield":{"id":"https://openalex.org/subfields/2739","display_name":"Public Health, Environmental and Occupational Health"},"field":{"id":"https://openalex.org/fields/27","display_name":"Medicine"},"domain":{"id":"https://openalex.org/domains/4","display_name":"Health Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/beta-endorphin","display_name":"beta-endorphin","score":1.0},{"id":"https://openalex.org/keywords/uterine-contraction","display_name":"uterine contraction","score":0.8109999895095825},{"id":"https://openalex.org/keywords/labor","display_name":"labor","score":0.9940000176429749},{"id":"https://openalex.org/keywords/plasma-endorphin-levels","display_name":"plasma endorphin levels","score":0.8799999952316284},{"id":"https://openalex.org/keywords/cervical-effacement","display_name":"cervical effacement","score":0.9139999747276306},{"id":"https://openalex.org/keywords/third-trimester","display_name":"third trimester","score":0.9309999942779541},{"id":"https://openalex.org/keywords/postpartum-recovery","display_name":"postpartum recovery","score":0.7070000171661377},{"id":"https://openalex.org/keywords/endogenous-opioids","display_name":"endogenous opioids","score":0.7409999966621399}],"concepts":[{"id":"https://openalex.org/C71924100","wikidata":"https://www.wikidata.org/wiki/Q11190","display_name":"Medicine","level":0,"score":0.8953009843826294},{"id":"https://openalex.org/C126322002","wikidata":"https://www.wikidata.org/wiki/Q11180","display_name":"Internal medicine","level":1,"score":0.7627564668655396},{"id":"https://openalex.org/C134018914","wikidata":"https://www.wikidata.org/wiki/Q162606","display_name":"Endocrinology","level":1,"score":0.7129161953926086},{"id":"https://openalex.org/C2776766599","wikidata":"https://www.wikidata.org/wiki/Q1751296","display_name":"Uterine contraction","level":3,"score":0.5850099325180054},{"id":"https://openalex.org/C2777557602","wikidata":"https://www.wikidata.org/wiki/Q2993328","display_name":"beta-Endorphin","level":2,"score":0.48430052399635315},{"id":"https://openalex.org/C163415756","wikidata":"https://www.wikidata.org/wiki/Q126473","display_name":"Contraction (grammar)","level":2,"score":0.4813447892665863},{"id":"https://openalex.org/C2779066055","wikidata":"https://www.wikidata.org/wiki/Q9612","display_name":"Uterus","level":2,"score":0.28714215755462646}],"mesh":[{"descriptor_ui":"D000328","descriptor_name":"Adult","qualifier_ui":null,"qualifier_name":null,"is_major_topic":false},{"descriptor_ui":"D001615","descriptor_name":"beta-Endorphin","qualifier_ui":"Q000097","qualifier_name":"blood","is_major_topic":true},{"descriptor_ui":"D005260","descriptor_name":"Female","qualifier_ui":null,"qualifier_name":null,"is_major_topic":false},{"descriptor_ui":"D006801","descriptor_name":"Humans","qualifier_ui":null,"qualifier_name":null,"is_major_topic":false},{"descriptor_ui":"D007743","descriptor_name":"Labor, Obstetric","qualifier_ui":"Q000097","qualifier_name":"blood","is_major_topic":true},{"descriptor_ui":"D011247","descriptor_name":"Pregnancy","qualifier_ui":null,"qualifier_name":null,"is_major_topic":false},{"descriptor_ui":"D011263","descriptor_name":"Pregnancy Trimester, Third","qualifier_ui":"Q000097","qualifier_name":"blood","is_major_topic":false},{"descriptor_ui":"D011863","descriptor_name":"Radioimmunoassay","qualifier_ui":null,"qualifier_name":null,"is_major_topic":false},{"descriptor_ui":"D014590","descriptor_name":"Uterine Contraction","qualifier_ui":"Q000502","qualifier_name":"physiology","is_major_topic":true}],"locations_count":2,"locations":[{"id":"doi:10.1016/0020-7292(90)90516-n","doi":"https://doi.org/10.1016/0020-7292(90)90516-n","is_oa":false,"landing_page_url":"https://doi.org/10.1016/0020-7292(90)90516-n","pdf_url":null,"source":{"id":"https://openalex.org/S4210216427","display_name":"International Journal of Gynecology & Obstetrics","issn_l":"0020-6695","issn":["0020-6695","0020-7292","1879-3479"],"is_oa":false,"is_in_doaj":false,"is_core":true,"listed_in":["cwts-core","dongbi-c","doyens","jufo-1","ki-jl-1","medline","norway-1","poland-70","russia-white-list-1","vabb-shw"],"host_organization":"https://openalex.org/P4310320990","host_organization_name":"Elsevier BV","host_organization_lineage":["https://openalex.org/P4310320990"],"host_organization_lineage_names":["Elsevier BV"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"International Journal of Gynecology & Obstetrics","raw_type":"journal-article"},{"id":"pmid:1979284","doi":null,"is_oa":false,"landing_page_url":"https://pubmed.ncbi.nlm.nih.gov/1979284","pdf_url":null,"source":{"id":"https://openalex.org/S4306525036","display_name":"PubMed","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"listed_in":[],"host_organization":"https://openalex.org/I1299303238","host_organization_name":"National Institutes of Health","host_organization_lineage":["https://openalex.org/I1299303238"],"host_organization_lineage_names":[],"type":"repository"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics","raw_type":"Comparative Study"}],"best_oa_location":null,"sustainable_development_goals":[{"score":0.9537000060081482,"display_name":"Good health and well-being","id":"https://metadata.un.org/sdg/3"}],"study_designs":[{"display_name":"Observational Study","id":"https://openalex.org/study-designs/observational-study"}],"awards":[],"funders":[],"has_content":{"pdf":false,"grobid_xml":false},"content_urls":null,"referenced_works_count":9,"referenced_works":["https://openalex.org/W1605320041","https://openalex.org/W1975336490","https://openalex.org/W1977454888","https://openalex.org/W2060334160","https://openalex.org/W2067599322","https://openalex.org/W2098231350","https://openalex.org/W2110627788","https://openalex.org/W2120033189","https://openalex.org/W2147119249"],"related_works":["https://openalex.org/W7061008209","https://openalex.org/W2520499576","https://openalex.org/W2401309873","https://openalex.org/W2065831924","https://openalex.org/W2110627788","https://openalex.org/W1969366888","https://openalex.org/W2085569298","https://openalex.org/W1971862233","https://openalex.org/W2067599322","https://openalex.org/W2132536062"],"abstract_inverted_index":{"Plasma":[0],"beta-endorphin":[1],"(BE)":[2],"levels":[3,57],"(8.6":[4],"+/-":[5,9,22,34,49],"0.8":[6],"pmol/l)":[7,24],"(mean":[8],"SE)":[10],"were":[11,58],"lower":[12],"in":[13,18],"the":[14],"third":[15],"trimester":[16],"than":[17,27,39,54,72,83],"non-pregnant":[19],"controls":[20],"(14.8":[21],"1.1":[23],"(P":[25,37,52],"less":[26,38,53,71,82],"0.001),":[28],"increased":[29],"during":[30,85],"labor,":[31],"to":[32,47,60],"29.3":[33],"4.4":[35],"pmol/l":[36,51],"0.005)":[40],"and":[41,74],"decreased,":[42],"72":[43],"h":[44],"after":[45],"delivery,":[46],"3.5":[48],"0.4":[50],"0.001).":[55],"BE":[56],"found":[59],"correlate":[61],"significantly":[62],"with":[63,75],"uterine":[64],"muscle":[65],"contraction":[66],"(r":[67,78],"=":[68,79],"0.966,":[69],"P":[70,81],"0.05)":[73,84],"cervical":[76],"effacement":[77],"0.974,":[80],"labor.":[86]},"counts_by_year":[{"year":2026,"cited_by_count":1},{"year":2024,"cited_by_count":1}],"updated_date":"2026-11-04T10:54:05.112534","created_date":"2016-06-24T00:00:00"}