Abstract：
OBJECTIVE:We previously demonstrated that chorion releases a factor that inhibits both spontaneous and oxytocin-stimulated myometrial contractility. Here, we investigate the mechanism of action of this unidentified substance. STUDY DESIGN:Myometrial strips from pregnant guinea pigs were mounted in an organ bath and contractility stimulated with oxytocin. RESULTS:Guinea pig chorion produced a time-dependent decrease in oxytocin-induced myometrial contractility. The ability of the chorion to reduce contractility was unaltered by inhibiting chorionic synthesis of either nitric oxide (N [omega]-nitro-L-arginine), carbon monoxide (tin-protoporphyrin), prostaglandins (indomethacin), or the myometrial cyclic guanosine monophosphate pathway (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalime-1-one and Rp-8Br-cGMP). In contrast, iberiotoxin, an inhibitor of large conductance Ca(2+)-activated K(+) channels reduced the quiescent effect of chorion by 40%; in contrast, inhibition of adenosine triphosphate-sensitive (glibenclamide) and voltage-gated K(+) channels (4amynopyridine) had no effect. CONCLUSION:Chorion-induced relaxation of oxytocin-stimulated myometrial contraction is, in great part, the product of a paracrine substance that opens myometrial large conductance Ca(2+)-activated K(+) channels.
journal_name
Am J Obstet Gynecoljournal_title
American journal of obstetrics and gynecologyauthors
Carvajal JA,Thompson LP,Weiner CPdoi
10.1067/mob.2003.102subject
Has Abstractpub_date
2003-01-01 00:00:00pages
84-91issue
1eissn
0002-9378issn
1097-6868pii
S0002937802714324journal_volume
188pub_type
杂志文章abstract：:We investigated the appearance of pulmonary lamellar bodies (LBs) in human amniotic fluid as a function of fetal age. We also studied their relationship to the lecithin/sphingomyelin (L/S) ratio and to the results of the rapid surfactant test (RST). LBs observed in amniotic fluid generally ranged in diameter from 1.5 ...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/0002-9378(80)90565-7
更新日期：1980-01-01 00:00:00
abstract：OBJECTIVE:Our purpose was to study the effects of isradipine, a dihydropyridine calcium channel blocker, on mother and fetus in the treatment of hypertensive disorders of pregnancy. STUDY DESIGN:The investigation was performed as a two-group, parallel, double-blind multicenter study of isradipine versus placebo. Fifty...
journal_title：American journal of obstetrics and gynecology
pub_type： 临床试验,杂志文章,随机对照试验
doi：10.1016/0002-9378(95)90357-7
更新日期：1995-09-01 00:00:00
abstract：OBJECTIVE:We report our experience with a technique for planning the final vaginal caliber and location of the vaginal apex in patients with severe vaginal prolapse. STUDY DESIGN:During the 2-year period ending April 1998, the technique was used in all 27 patients who were undergoing vaginal repair of prolapse perform...
journal_title：American journal of obstetrics and gynecology
pub_type： 临床试验,杂志文章
doi：10.1067/mob.2000.107658
更新日期：2000-08-01 00:00:00
abstract：OBJECTIVE:Our purpose was to investigate perfusion pressure changes ex vivo induced by angiotensin II on fetoplacental vasculature pretreated with low-dose acetylsalicylic acid. STUDY DESIGN:Two cotyledons from each of 12 placentas were perfused. The intervillous space of one cotyledon was infused with acetylsalicylic...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/s0002-9378(97)70021-8
更新日期：1997-11-01 00:00:00
abstract：:The mechanical properties of the chorioamniotic membranes have been studied by several investigators over the past 100 years. No relationship between membrane strength, as measured by rupture tension, and premature or non-premature rupture of the membranes has been demonstrable. In the present study, several measures ...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/0002-9378(76)90788-2
更新日期：1976-07-01 00:00:00
abstract：OBJECTIVE:Our purpose was to evaluate the outcome of infants who underwent successful resuscitation after initial Apgar scores of 0 at both 1 and 5 minutes. STUDY DESIGN:Eligible infants were identified through the perinatal database at the University of Tennessee, Memphis. Hospital records and long-term outcomes, whe...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1067/mob.2000.104951
更新日期：2000-05-01 00:00:00
abstract：OBJECTIVE:Gestational diabetes mellitus (GDM) is thought to modify the pattern of placental transcriptome. In a microarray study and a confirmatory quantitative real-time reverse transcription-polymerase chain reaction study, we investigated global placental gene expression in GDM. STUDY DESIGN:Ribonucleic acid was ex...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/j.ajog.2008.08.022
更新日期：2009-02-01 00:00:00
abstract：:Ultrasonography can accurately determine phenotypic sex differences from those of the genetic sex. Two cases were identified; they were the result of a translocation of the SRY gene from the Y chromosome to the X chromosome during meiosis. An ultrasonographic difference may represent an otherwise unsuspected genetic a...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/s0002-9378(99)70673-3
更新日期：1999-04-01 00:00:00
abstract：OBJECTIVES:This study aimed to determine whether administration of lamivudine to pregnant women with chronic hepatitis B in the third trimester is a cost-effective strategy in preventing perinatal transmission. STUDY DESIGN:We developed a decision analysis model to compare the cost-effectiveness of 2 management strate...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/j.ajog.2012.06.001
更新日期：2012-09-01 00:00:00
abstract：:Significant public health disparities exist surrounding teen and unplanned pregnancy in the United States. Women of color and those with lower education and socioeconomic status are at much greater risk of unplanned pregnancy and the resulting adverse outcomes. Unplanned pregnancies reduce educational and career oppor...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章,评审
doi：10.1016/j.ajog.2016.02.017
更新日期：2016-06-01 00:00:00
abstract：:This study was designed to test the hypothesis that maternal marijuana smoking impairs placental oxygen transfer in late ovine pregnancy by disrupting perfusion balance between the maternal and fetal placental circulations. Placental hemodynamics were assessed in nine chronically prepared ewes 1 hour after exposure to...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/0002-9378(88)90569-8
更新日期：1988-12-01 00:00:00
abstract：:Data are presented to define a unique group of preeclamptic/eclamptic patients with the finding of hemolysis (H), elevated liver enzymes (EL), and a low platelet count (LP). This entity has been termed the HELLP syndrome and may occur when the usual clinical findings to diagnose severe preeclampsia are absent. Often t...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/s0002-9378(16)32330-4
更新日期：1982-01-15 00:00:00
abstract：:Spontaneous preterm birth is a heterogeneous phenotype. A multitude of pathophysiologic pathways culminate in the final common denominator of cervical softening, shortening, and dilation that leads to preterm birth. A precise description of specific microstructural changes to the cervix is imperative if we are to iden...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章,评审
doi：10.1016/j.ajog.2012.05.015
更新日期：2012-11-01 00:00:00
abstract：OBJECTIVE:This study was undertaken to measure fetal renal volume by means of three-dimensional ultrasonography and to use those data to establish the accurate constant and formula for fetal renal volume assessment with two-dimensional ultrasonography. STUDY DESIGN:Singleton fetuses between 15 and 40 weeks' gestation ...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/s0002-9378(00)70227-4
更新日期：2000-02-01 00:00:00
abstract：:Rates of short-interval pregnancies that result in unintended pregnancies remain high in the United States and contribute to adverse reproductive health outcomes. Long-acting reversible contraception methods have annual failure rates of <1%, compared with 9% for oral contraceptive pills, and are an effective strategy ...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/j.ajog.2018.03.007
更新日期：2018-06-01 00:00:00
abstract：OBJECTIVE:Fetuses with solid, highly vascularized sacrococcygeal teratomas can die as a result of the vascular steal syndrome. This is the first report in which a percutaneous technique, radiofrequency ablation, was used to interrupt blood flow to a sacrococcygeal teratoma in 4 human fetuses. STUDY DESIGN:A radiofrequ...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1067/mob.2001.110446
更新日期：2001-02-01 00:00:00
abstract：OBJECTIVE:The objective of the study was to evaluate the risk for bacterial vaginosis (BV) in a douching cessation trial. STUDY DESIGN:Thirty-nine reproductive-age women who reported use of douche products were enrolled into a 20-week study consisting of a 4 week douching observation (phase I) followed by 12-weeks of ...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/j.ajog.2007.11.043
更新日期：2008-06-01 00:00:00
abstract：:A case is described in which a leiomyoma of the ovary was accompanied by hydrothorax. There was no reaccumulation of fluid after oophorectomy. ...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/0002-9378(89)90260-3
更新日期：1989-07-01 00:00:00
abstract：:The therapeutic effect of magnesium sulfate remains unknown. Its role as an anticonvulsant is controversial. The effect of pretreatment with parenteral magnesium sulfate on the ability to initiate penicillin-induced seizure foci in anesthetized cats was studied. All animals in the experimental group achieved serum mag...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/0002-9378(89)90482-1
更新日期：1989-02-01 00:00:00
abstract：OBJECTIVE:The objective of the study was to assess the prevalence of levator ani denervation and reinnervation 6 months after the first delivery. STUDY DESIGN:Ninety-six primigravida women underwent quantitative electromyography of the levator ani during the third trimester and twice postpartum. A 95% confidence inter...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/j.ajog.2008.12.044
更新日期：2009-05-01 00:00:00
abstract：:The progesterone antagonist onapristone was used in guinea pigs during late pregnancy (43 +/- 2 days after coitus) and before term (day 61 after coitus) to investigate the role of progesterone on uterine reactivity to exogenous oxytocin, concentration of oxytocin receptors, and gap junctions in the myometrium. Onapris...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/0002-9378(91)90030-u
更新日期：1991-12-01 00:00:00
abstract：OBJECTIVE:Our aim was to determine the chorionic and amniotic types in multifetal pregnancies with transvaginal ultrasonography at > or = 14 weeks' gestation. STUDY DESIGN:Two hundred twelve multifetal pregnancies were scanned transvaginally at or before 14 weeks' gestation. The number of fetuses and the chorionic and...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/s0002-9378(94)70291-8
更新日期：1994-03-01 00:00:00
abstract：OBJECTIVE:The purpose of this study was to determine the contribution of randomization to nicotine replacement therapy (NRT), sociodemographic and psychosocial factors, and pregnancy and medical history to serious perinatal adverse events among pregnant smokers. STUDY DESIGN:We performed a retrospective review of all ...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章,随机对照试验
doi：10.1016/j.ajog.2009.06.006
更新日期：2009-10-01 00:00:00
abstract：OBJECTIVE:The objective of this study was to assess the reliability and validity of an objective structured assessment of technical skills (OSATS) for repair of fourth-degree obstetric lacerations on a surgical model. STUDY DESIGN:Three blinded judges reviewed recordings of 20 junior and 20 senior obstetrics-gynecolog...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/j.ajog.2008.07.054
更新日期：2008-12-01 00:00:00
abstract：:Epidermal inclusion cysts are a late complication of female genital circumcision, which is a practice that affects 125 million women primarily from Africa and the Middle East. A 30-year-old woman, gravida 4, para 1, presented to our clinic with an 8-year history of a slowly enlarging periclitoral mass. The patient had...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/j.ajog.2016.03.026
更新日期：2016-06-01 00:00:00
abstract：OBJECTIVES:Our purpose was to (1) determine the value of amniotic fluid interleukin-6 determination in the detection of microbial invasion of the amniotic cavity and (2) compare interleukin-6 to other rapid tests in the evaluation of preterm labor. STUDY DESIGN:Amniotic fluid interleukin-6 was determined quantitativel...
journal_title：American journal of obstetrics and gynecology
pub_type： 临床试验,杂志文章
doi：10.1016/s0002-9378(94)70057-5
更新日期：1994-10-01 00:00:00
abstract：OBJECTIVE:To quantify expression of progesterone receptor (PR) messenger RNA (mRNA) isoforms in fetal membranes, and to determine whether these levels change in culture. STUDY DESIGN:Placentas from women undergoing term cesarean delivery before labor were collected. Layers of amnion, chorion, and decidua were separate...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/j.ajog.2006.06.040
更新日期：2006-10-01 00:00:00
abstract：:In many developing countries, services to prevent the mother-to-child transmission (PMTCT) of human immunodeficiency virus (HIV) operate with limited contact with HIV care and treatment programs, despite significant advances in the accessibility of both services. There is a need to deliver more complex multidrug PMTCT...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章,评审
doi：10.1016/j.ajog.2007.03.068
更新日期：2007-09-01 00:00:00
abstract：OBJECTIVE:The purpose of this study was to test the hypothesis that interleukin-10 can prevent white matter injury in neonatal rats that are born to infected dams. STUDY DESIGN:Timed pregnant rats (day 17) were assigned to the following treatment groups: (1) saline control (n = 5 rats), (2) Escherichia coli- infected ...
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/j.ajog.2004.06.093
更新日期：2004-10-01 00:00:00
abstract：:We first performed a vaginosonic scan and then determined the serum human chorionic gonadotropin (beta-hCG) concentration (Second International Standard) in 52 women at an early gestational age to establish criteria for the earliest possible identification of an intrauterine pregnancy by this new ultrasound technique....
journal_title：American journal of obstetrics and gynecology
pub_type： 杂志文章
doi：10.1016/0002-9378(88)90039-7
更新日期：1988-03-01 00:00:00
