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1.
Basal levels and ACTH-induced increments of serum 17 alpha-hydroxyprogesterone (170HP), cortisol, 4-androstene-3,17-dione (A-4), dehydroepiandrosterone (DHA), and dehydroepiandrosterone sulphate (DHAS) were related to the degree of obesity and to trabecular bone mineral density in 29 postmenopausal women. The ACTH-induced increment of 170HP (delta 170HP) was negatively correlated to basal DHA and delta DHA. Positive correlations were found between obesity, expressed as Broca's index, and delta DHA and the delta DHA/delta 170HP ratio. Bone mineral density was positively correlated to basal DHAS, delta DHA, delta DHAS and the delta DHA/delta 170HP ratio, and negatively correlated to delta 170HP. DHA and 170HP represent a crossroad in adrenocortical steroid biosynthesis, leading to delta 5-androgens and glucocorticoids as main products. Besides age, obesity may also influence the intra-adrenal distribution between these two main steroidogenic pathways. The results suggest that differences at a very early stage of the adrenal steroidogenesis may influence calcium homeostasis in the post-menopausal woman.  相似文献   
2.
Organization of the IGHV genes (n=108) on single human chromosomes has been determined by detecting these sequences in single sperm using multiplex PCR amplification followed by microarray detection. A total of 374 single sperm samples from five Caucasian males were studied. Three deletion/insertion polymorphisms (Del I-Del III) with deletion allele frequencies ranging from 0.1 to 0.3 were identified. Del I is a previously reported polymorphism affecting three IGHV genes (IGHV1-8, IGHV3-9, and IGHV2-10). Del II affects a region 2-18 kb containing two pseudogenes IGHV(II)-28.1 and IGHV3-29, and Del III spans approximately 21-53 kb involving genes IGHV4-39, IGHV7-40, IGHV(II)-40-1, and IGHV3-41. Deletion alleles of both Dels II and III were found in a heterozygous state, and therefore, could not be easily detected if haploid samples were not used in the study. Results of the present study indicate that deletions/insertions together with other possible chromosomal rearrangements may play an important role in forming the genetic structure of the IGHV region, and may significantly contribute to antibody diversity. Since these three polymorphisms are located within or next to the 3' half of the IGHV region, they may have an important role in the expressed IGHV gene repertoire during immune response.  相似文献   
3.
Symphysis fundus heights (SF) were measured approximately 15 times during pregnancy in a consecutive series of 2941 women with regular menstrual cycles and known last menstrual period. A reference SF chart from 17 to 40 weeks of pregnancy was derived from measurements in 1350 of these women who were healthy, and heights and pre-pregnancy weights within the 10th and 90th centiles and were delivered vaginally of healthy infants with a birthweight/length ratio within +/- 2 SD. The reference chart was used to predict fetal growth deviations in the unselected series of pregnancies. The effectiveness of SF measures to detect fetuses with an infant birthweight/length ratio below -2 SD or a birthweight below the 10th centile was low; the sensitivity was only 16.7 and 26.6% and the predictive value of positive screening result was 1.8 and 18.0%, respectively. Corresponding values for fetuses with an infant birthweight/length ratio above + 2 SD or a birthweight above the 90th centile were 31.8 and 37.5% and 3.3 and 24.5%, respectively. Symphysis fundus (SF) measurement has thus been found to be of limited value as a screening method to detect abnormal size at birth.  相似文献   
4.
The hormonal milieu at embryo implantation after in-vitro fertilization was investigated. Superstimulation was accomplished with clomiphene citrate and human menopausal gonadotrophin (HMG) injections followed by ovulation induction with human chorionic gonadotrophin (HCG). Venous blood samples were drawn on days 2 and 8, the day of oocyte recovery being day 0. Fifteen women with successful implantation, defined as an ultrasound-verified pregnancy, were compared to 42 women with unsuccessful implantation, using a three-way analysis of variance. Oestradiol, progesterone, testosterone and sex hormone binding globulin (SHBG) did not differ between the two groups. However, the ratios of oestradiol/progesterone and of testosterone/SHBG were significantly higher in the non-fertile cycles, both on day 2 and on day 8 (P less than 0.05). Furthermore, there was a highly significant decrease in oestradiol, progesterone and testosterone between days 2 and 8 in fertile as well as in non-fertile cycles (P less than 0.001) and a highly significant increase in SHBG from day 2 to day 8 in both groups (P less than 0.001). The higher testosterone/SHBG ratio in the non-pregnant women implies a relative hyperandrogenicity in this group that might have adversely affected the uterine receptivity.  相似文献   
5.
The uteroplacental blood flow was measured before and during epidural anaesthesia for caesarean section in 11 women. The blood flow was measured with dynamic placental scintigraphy. After an i.v. injection of indium-113m chloride, the gamma radiation over the placenta was recorded with a computer-linked scintillation camera. The uteroplacental blood flow could be calculated from the isotope accumulation curve. The anaesthesia was performed with bupivacaine plain 0.5%, 18-22 ml and a preload of a balanced electrolyte solution 10 ml/kg b.w. was given. The placental blood flow decreased in eight patients and increased in three with a median change of -21%, not being statistically significant. No correlation between maternal blood pressure and placental blood flow was found.  相似文献   
6.
Free amino acid concentrations were determined in maternal plasma and amniotic fluid (AF) under standardized and unstressed conditions in four groups of women comprising 6 gestational and 13 type I diabetics, 10 women with small-for-gestational-age (SGA) infants, and 18 healthy control women between 36 and 39 weeks of gestation. Plasma values for branched chain amino acids (the sum of leucine, isoleucine and valine) did not differ significantly between the four groups. The corresponding values in AF were significantly higher (P less than 0.05) in the type I diabetic group and significantly lower (P less than 0.05) in the gestational diabetic group as compared to the control group. The mean AF C-peptide concentration was elevated but not significantly so in gestational (0.69 nmol/l) or type I diabetic (0.54 nmol/l) pregnancies and significantly lower (P less than 0.05) in women with SGA infants (0.28 nmol/l) as compared to the control group (0.38 nmol/l). There was a significant correlation between C-peptide in AF and branched chain amino acids in maternal plasma (r = 0.63; P less than 0.05) as well as to maternal blood glucose (r = 0.79; P less than 0.01) in the type I diabetic group, which merely suggests a greater beta cell reactivity to insulin secretagogues in offspring of diabetic mothers. The correlation between AF C-peptide and branched chain amino acids in maternal plasma was significantly inverse in women with SGA infants (r = -0.75; P less than 0.05). Both individual, branched chain, or total amino acid concentration in AF were unrelated to AF C-peptide.  相似文献   
7.
The effect on uteroplacental blood flow of an epidural anaesthesia containing adrenaline for caesarean section was investigated in ten healthy women using dynamic placental scintigraphy with indium-113m and a computer-linked gamma camera. The epidural anaesthesia was performed with 18-22 ml bupivacaine 5 mg/ml with adrenaline 2.5 micrograms/ml followed by an i.v. balanced electrolyte infusion of 10 ml/kg b.w. A significant median decrease in the total maternal placental blood flow of 34% was found (P less than 0.01). There was also a significant decrease in maternal mean blood pressure of 3 mmHg (0.4 kPa) (P less than 0.05) and a significant negative correlation between the change in maternal blood pressure and the change in uteroplacental blood flow (r = -0.69, P less than 0.05).  相似文献   
8.
Summary Enprofylline 1 mg/kg, a new potent antiasthmatic xanthine derivative, which is mainly eliminated by renal excretion, was given intravenously to 6 normal subjects with and without oral pretreatment with 1 g probenecid. The latter caused a drop in the average total body clearance of enprofylline from 21 to 9.8 l/h, and in the average renal clearance from 17 to 8.0 l/h. The average half-life increased from 1.8 to 3.0 h. The volumes of distribution, Vz and Vss, both fell by about 25%, indicating that probenecid had restricted the distribution of enprofylline in the body. The plasma protein binding of enprofylline was not altered by probenecid. The results confirm the opinion that active tubular secretion accounts for a large proportion of the total elimination of enprofylline.  相似文献   
9.
The orphan receptor GPR55 is a novel cannabinoid receptor   总被引:11,自引:0,他引:11  
BACKGROUND: The endocannabinoid system functions through two well characterized receptor systems, the CB1 and CB2 receptors. Work by a number of groups in recent years has provided evidence that the system is more complicated and additional receptor types should exist to explain ligand activity in a number of physiological processes. EXPERIMENTAL APPROACH: Cells transfected with the human cDNA for GPR55 were tested for their ability to bind and to mediate GTPgammaS binding by cannabinoid ligands. Using an antibody and peptide blocking approach, the nature of the G-protein coupling was determined and further demonstrated by measuring activity of downstream signalling pathways. KEY RESULTS: We demonstrate that GPR55 binds to and is activated by the cannabinoid ligand CP55940. In addition endocannabinoids including anandamide and virodhamine activate GTPgammaS binding via GPR55 with nM potencies. Ligands such as cannabidiol and abnormal cannabidiol which exhibit no CB1 or CB2 activity and are believed to function at a novel cannabinoid receptor, also showed activity at GPR55. GPR55 couples to Galpha13 and can mediate activation of rhoA, cdc42 and rac1. CONCLUSIONS: These data suggest that GPR55 is a novel cannabinoid receptor, and its ligand profile with respect to CB1 and CB2 described here will permit delineation of its physiological function(s).  相似文献   
10.
Serum concentrations of sex hormone-binding globulin (SHBG), oestradiol-17 beta progesterone and testosterone were measured in 23 gonadotrophin-stimulated menstrual cycles and in the implantation period [days 11-19 after human chorionic gonadotrophin (HCG) injection] following in-vitro fertilization and embryo transfer. Nine cycles resulted in successful pregnancies, one pregnancy ended in spontaneous abortion (week 14) and 13 cycles were without conception. SHBG levels were significantly elevated above pretreatment values from day 3 after HCG injection onwards. A significant positive correlation was found between increments in SHBG (delta SHBG) during the luteal phase and oestradiol/testosterone ratios during the follicular and luteal phases. In the pregnant cycles a significant positive correlation was also found between delta SHBG during the implantation period and oestradiol/testosterone ratios during the luteal phase and the implantation period. Significant negative correlations were found between delta SHBG and testosterone during the luteal phase in pregnant and non-pregnant women as well as between delta SHBG during the period corresponding to implantation and testosterone during the luteal phase in non-pregnant cycles. The results may reflect a modulating action of the oestrogen/androgen balance upon SHBG levels in subjects with supraphysiological oestradiol levels, such as in stimulated cycles and in very early pregnancy.  相似文献   
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