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31.
The aim of this study was to compare 70 couples who had conceived by in- vitro fertilization (IVF) with 63 matched controls for the prevalence of anxiety and quality of attachment to the baby during pregnancy. Results for mothers showed no group differences using a global measure of anxiety, the Spielberger State-Trait Anxiety Inventory. However, pregnancy-specific measures revealed significantly higher levels of anxiety in IVF mothers about the survival and normality of their unborn babies, about damage to their babies during childbirth and about separating from their babies after birth. When IVF mothers were differentiated according to the number of treatment cycles, more differences in anxiety level were revealed, with most increases occurring in mothers who had experienced two or more treatment cycles. IVF fathers did not differ from controls on the global anxiety measure. No data on pregnancy-specific anxiety were available for fathers. Neither IVF mothers nor IVF fathers differed from controls on measures of attachment to the baby during pregnancy. Results are discussed in the context of the need for researchers to employ differentiated and issue-specific measures to identify concerns that may be unique to IVF couples. Clinical implications regarding the need for psychological support during pregnancy are also discussed.   相似文献   
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Surface-immobilized polyethylene oxide for bacterial repellence.   总被引:1,自引:0,他引:1  
Polyethylene terephthalate films were surface-modified with polyethylene oxide (18,500 g/mol) using a solution technique described previously. These films were investigated for their resistance to bacterial adhesion. Three bacterial strains most commonly associated with implant infections, Staphylococcus epidermidis, Staphylococcus aureus and Pseudomonas aeruginosa, were cultured in tryptic soya broth, human plasma and human serum on the polymeric substrates. Significant reductions (between 70 and 95%) in adherent bacteria were observed on the polyethylene oxide-modified substrates compared to the untreated control polyethylene terephthalate. Surface modification with polyethylene oxide may reduce the risk of implant-associated infections. Plasma fibrinogen was observed to play an important role in the adhesion of all three of these species on both the polyethylene oxide-modified and control polyethylene terephthalate materials.  相似文献   
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Increased antiphospholipid antibody prevalence has been demonstrated by a number of recent studies in in-vitro fertilization (IVF) patients but the potential effects of antiphospholipid antibodies on the different components of the reproductive process and the consideration of whether to test IVF patients for antiphospholipid antibodies are controversial. The present study was undertaken to investigate the possible association between the presence of circulating antiphospholipid antibodies (namely the lupus anticoagulant and anticardiolipin antibodies), among a series of 21 consecutive IVF patients having a clinical spontaneous abortion after their first embryo transfer. As a control group (n=42), the nearest IVF cycle resulting in an ongoing pregnancy before and after each miscarried IVF cycle (i.e. the closest cycles in temporal relationship to the index cycle) was used. One patient (4.8%) in the study group and two women (4.8%) among controls were seropositive for antiphospholipid antibodies. These low and similar seropositivity rates found in the two groups studied lead us to conclude that antiphospholipid antibodies testing in IVF patients should be considered only in those women having repeated failures of implantation/clinical abortion after embryo transfer but not in an infertile general population reaching an IVF programme.   相似文献   
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The objective was to demonstrate bioequivalence between s.c. and i.m. administration of Humegon (FSH/LH ratio 1:1) and Normegon (FSH/LH ratio 3:1). In two randomized, single-centre, cross-over studies, 18 healthy volunteers on each formulation were assigned to one of the two administration sequences. Subjects were given single doses of one of the above gonadotrophins after endogenous gonadotrophin production had first been suppressed using high-dose oral contraceptive. Subsequently, rate (Cmax, tmax) and extent (AUC) of absorption of follicle stimulating hormone (FSH) and luteinizing hormone (LH) were determined for 14 days. For Cmax and AUC, analysis of variance (ANOVA) was performed on log-transformed data and for tmax ANOVA was performed on ranks. Intramuscular and s.c. injections of Humegon were bioequivalent with respect to the main pharmacokinetic parameters, being AUC and Cmax of FSH absorption. Intramuscular and s.c. injections of Normegon were bioequivalent with respect to the AUC of FSH and not bioequivalent with respect to the Cmax of FSH. For tmax of FSH as well as for most LH variables of both preparations, bioequivalence could not be proven due to the high intra- and interindividual variability and/or concentrations being close to the detection limit. Thus, the main pharmacokinetic FSH variables after i.m. and s.c. administration of Humegon and Normegon were bioequivalent.   相似文献   
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A pilot study was designed to examine whether the outcome of embryo transfer in women with a hydrosalpinx might be improved by surgical drainage of the hydrosalpinx at the time of oocyte collection for in- vitro fertilization treatment. A comparative, controlled but retrospective analysis of the results was performed of all women with infective tubal damage aged <40 years old, who had ovulatory cycles, a normal uterus and a partner with normal spermatozoa. A standardized treatment regimen was used. A maximum of three embryos were transferred. Hydrosalpinx was defined by prior hysterosalpingography and/or laparoscopy with transcervical dye injection. A total of 237 embryo transfer cycles in women with hydrosalpinges (tubal distension not visible in 151, visible but not drained in 30 and drained in 56) were compared with 705 embryo transfer cycles in women with tubal disease but no hydrosalpinx. Results were analysed in the first three cycles but also separately in the first cycle to check for bias. Success rates were higher in the first cycle, but did not significantly influence overall differences. Implantation rates were significantly reduced overall in the hydrosalpinx group (8.0 versus 13.2% for controls; P < 0.001), being 8.3% (P < 0.01) in the subgroup without evident tubal distension and 7.5% (not significant) in the drained hydrosalpinx group. This study shows that tubal damage with distal occlusion is associated with a marked reduction in embryo implantation, even in the absence of obvious fluid distension. Surgical drainage of distended hydrosalpinges appears to offer no benefit.   相似文献   
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Osteoblasts exhibit a more differentiated morphology on surfaces with rough microtopographies. Surface effects are often mediated through integrins that bind the RGD motif in cell attachment proteins. Here, we tested the hypothesis that modulating access to RGD binding sites can modify the response of osteoblasts to surface microtopography. MG63 immature osteoblast-like cells were cultured on smooth (Ti sputter-coated Si wafers) and rough (grit blasted/acid etched) Ti surfaces that were modified with adsorbed monomolecular layers of a comb-like graft copolymer, poly-(L-lysine)-g-poly(ethylene glycol) (PLL-g-PEG), to limit nonspecific protein adsorption. PLL-g-PEG coatings were functionalized with varying amounts of an integrin-receptor-binding RGD peptide GCRGYGRGDSPG (PLL-g-PEG/PEG-RGD) or a nonbinding RDG control sequence GCRGYGRDGSPG (PLL-g-PEG/PEG-RDG). Response to PLL-g-PEG alone was compared with response to surfaces on which 2-18% of the polymer sidechains were functionalized with the RGD peptide or the RDG peptide. To examine RGD dose-response, peptide surface concentration was varied between 0 and 6.4 pmol/cm(2). In addition, cells were cultured on uncoated Ti or Ti coated with PLL-g-PEG or PLL-g-PEG/PEG-RGD at an RGD surface concentration of 0.7 pmol/cm(2), and free RGDS was added to the media to block integrin binding. Analyses were performed 24 h after cultures had achieved confluence on the tissue culture plastic surface. Cell number was reduced on smooth Ti compared to plastic or glass and further decreased on surfaces coated with PLL-g-PEG or PLL-g-PEG/PEG-RDG, but was restored to control levels when PLL-g-PEG/PEG-RGD was present. Alkaline phosphatase specific activity and osteocalcin levels were increased on PLL-g-PEG alone or PLL-g-PEG/PEG-RDG, but PLL-g-PEG/PEG-RGD reduced the parameters to control levels. On rough Ti surfaces, cell number was reduced to a greater extent than on smooth Ti. PLL-g-PEG coatings reduced alkaline phosphatase and increased osteocalcin in a manner that was synergistic with surface roughness. The RDG peptide did not alter the PLL-g-PEG effect but the RGD peptide restored these markers to their control levels. PLL-g-PEG coatings also increased TGF-beta1 and PGE(2) in conditioned media of cells cultured on smooth or rough Ti; there was a 20x increase on rough Ti coated with PLL-g-PEG. PLL-g-PEG effects were inhibited dose dependently by addition of the RGD peptide to the surface. Free RGDS did not decrease the effect elicited by PLL-g-PEG surfaces. These unexpected results suggest that PLL-g-PEG may have osteogenic properties, perhaps correlated with effects that alter cell attachment and spreading, and promote a more differentiated morphology.  相似文献   
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