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81.
Hydrosalpinges adversely affect markers of endometrial receptivity 总被引:22,自引:10,他引:22
Meyer WR; Castelbaum AJ; Somkuti S; Sagoskin AW; Doyle M; Harris JE; Lessey BA 《Human reproduction (Oxford, England)》1997,12(7):1393-1398
While in-vitro fertilization (IVF) was initially developed in women with
tubal factor infertility, recent clinical studies have suggested that the
presence of hydrosalpinges lowers implantation and pregnancy rates. We
postulated that these hydrosalpinges cause impaired endometrial
receptivity. A total of 103 women with hydrosalpinges were prospectively
evaluated, and compared with 55 infertile and 44 fertile controls. All
women had endometrial biopsies during the window of implantation, analysed
by conventional histological criteria, and also stained for three integrin
markers of endometrial receptivity (alpha1beta1, alpha4beta1 and alpha
vbeta3). Women with hydrosalpinges (cases) expressed significantly less of
the alpha vbeta3 integrin compared with controls. There was no difference
in expression of alpha1beta1 or alpha4beta1 among groups. A significantly
greater number of cases had out of phase histology and missing alpha vbeta3
(type I defects) and absent integrin expression despite normal histological
maturation (type II) defects, compared with controls. Of 20 women with
impaired endometrial receptivity who were also biopsied after hydrosalpinx
surgery, 70% demonstrated increased alpha vbeta3 expression. Seventy-seven
percent of type I and 57% of type II defects were corrected
postoperatively. Using markers of endometrial receptivity, this study
demonstrates that inflammatory hydrosalpinges have an adverse effect on
endometrial receptivity, which in some cases may be overcome by surgical
treatment of the hydrosalpinx.
相似文献
82.
采用生物素结合的葡聚糖胺顺行示踪法研究了大鼠视皮质主要胼胝体投射区即17/18a交界区胼胝体轴突的生后发育和形态。在生后5天时,此交界区胼胝体轴突从白质向灰质Ⅰ层垂直生长,在灰质内仅有极少量的侧支抽芽。至生后13天时,皮质Ⅰ层最先出现致密的由胼胝体轴突终支组成的终末丛。到生后17天时,类似的终末丛也见于皮质Ⅱ/Ⅲ,Ⅴ和Ⅵ层,这种分布型式与成年大鼠者相似。以上结果表明,绝大部分胼胝体轴突首先生长到达Ⅰ层并先在Ⅰ层发出终支,然后再在其它皮质层发出侧支及终支,因而提示皮质Ⅰ层在胼胝体联系的生后发育中可能发挥重要作用。 相似文献
83.
Claire Mayers Gerard Leavey Christina Vallianatou Chris Barker 《Clinical psychology & psychotherapy》2007,14(4):317-327
This qualitative study explored the process of help‐seeking and therapy among clients with religious or spiritual beliefs. Ten clients who were currently in, or had recently finished, therapy were interviewed. Participants reported using their religious or spiritual beliefs to cope with their psychological problems before and during therapy. Prior to therapy, they were worried that secular‐based help might weaken their faith. However, the experience of having psychological distress and the process of receiving therapy were both perceived as strengthening to faith and ultimately part of a spiritual journey. Contrary to expectations, a match between the spirituality or religious affiliation of the therapist and client was not considered important. This implies that the ‘religiosity gap’ between secular therapists and clients with religious/spiritual beliefs is bridgeable. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
84.
The presence of a receptor for the Fc of IgM (muFcR) was demonstrated on the pathological B cells of all of sixteen patients with hairy-cell leukaemia and most, but not all, of twenty-four cases of chronic lymphocytic leukaemia, by a rosette method employing ox erythrocytes sensitized with purified IgM (EAm). This muFcR was also demonstrated on a small population of normal human mononuclear cells from peripheral blood. Pathological B cells with this receptor (Bm) simultaneously expressed a different and distinct receptor for the Fc of IgG, and were detectable without preincubation in medium containing foetal calf serum (FCS). The muFcR on B cells was blocked by Fc5mu and IgM, but not by F(ab')2mu fragments, or by IgG, whether monomeric or aggregated. Monomeric IgM and IgM bound to its antigen blocked much more effectively than pentameric IgM. B cells also possessed surface immunoglobulin and the Ia-like P29, 34 antigen, and an antiserum to this antigen blocked the muFcR. The muFcR on B cells differs in a number of ways from the muFcR reported on T cells, and these differential characteristics are discussed in some detail. The muFcR was rapidly shed and resynthesized when washed Bm cells were maintained in medium not containing FCS and the general importance of this phenomenon in any study of muFcR is considered. It is suggested that Bm cells are memory cells and that the muFcR plays a part in the immune response. 相似文献
85.
Cellular adhesion molecules play a central role in leucocyte migration through peripheral blood and tissues. A crucial stage in these events in selectin-mediated adhesion involving E-selectin expressed on activated endothelium interacting with a range of carbohydrate ligands expressed by specific subpopulations of leucocytes. As such mechanisms may be relevant to bone marrow-derived dendritic epidermal Langerhans' cell (LC) migration, expression of these carbohydrate ligands was assessed immunocytochemically in whole skin biopsies and in epidermal cell suspensions obtained from adult humans. Double-labelling experiments revealed that sialyl Lewis x, recognized by the monoclonal antibody CSLEX1, was expressed on epidermal LC (n = 9). Furthermore, expression was enhanced at 24 hr following epicutaneous application of antigen and in the inflammatory disorder psoriasis (n = 10). E-selectin was concomitantly strongly expressed on dermal endothelium in psoriasis and allergic contact dermatitis. Intradermal injection of the T-cell-derived cytokine interferon-gamma (IFN-gamma) led to increased LC expression of sialyl Lewis x. In epidermal cell suspensions, in contrast to keratinocytes, CD1a+ cells expressed sialyl Lewis x, intensity of which was enhanced after 4 days in culture. CSLEX1 staining could be abolished and CD15 (non-sialated Lewis x) expression induced by saponification and treatment with neuraminidase. Expression of other selectin ligands was also examined. While the cutaneous lymphocyte antigen defined by the monoclonal antibody HECA-452 reacted with a small minority of LC, sialyl Lewis a and sulphatide were not expressed under any experimental conditions. These studies indicate that E-selectin-sialyl Lewis x interactions are potentially important in LC migration, both into and out of skin. 相似文献
86.
87.
H.F.L Mark M.E Rausch W.M Taylor A Huth S Mark K Santoro K Zolnierz K Ferreira B.E Barker 《Cancer Genetics and Cytogenetics》1998,100(2):93-133
Both flow cytometry and fluorescence in situ hybridization (FISH) are useful techniques in the analysis of cancer tissues. When the two are used in the study of the same specimens, they are usually performed in parallel, separately. This is problematic where there is a scarcity of material, making completion of both studies impossible. Fluorescence in situ hybridization procedures that will utilize excess material discarded from flow cytometry would be advantageous. The present report describes an optimized protocol for performing sequential flow cytometry and FISH using formalin-fixed paraffin-embedded archival material. Although breast cancer tissues were used in this initial study, the protocol is applicable to other cancer tissues as well. 相似文献
88.
Schover LR; Thomas AJ; Falcone T; Attaran M; Goldberg J 《Human reproduction (Oxford, England)》1998,13(4):862-866
Many couples undergoing in-vitro fertilization (IVF) are at a higher risk
of having a child with a genetic abnormality. In a sample of 55 consecutive
couples starting IVF, only 33% had no genetic risk factor. The most common
genetic risks were advanced maternal age and possible abnormalities
associated with severe male infertility. Despite education on these risks,
71% of couples had no interest in receiving formal genetic counselling.
Only 14% of couples at risk would consider using a gamete donor to avoid
transmitting a genetic disorder to a child. The triple test to screen for
fetal abnormalities was acceptable to 82% of couples, but only 47% planned
to have amniocentesis or chorionic villi sampling. Couples were
significantly more likely to opt for prenatal testing if they would
consider terminating a pregnancy should the fetus have a severe genetic
abnormality (P < 0.01). Roman Catholic couples tended to have more
conservative attitudes about pregnancy termination. Socio-economic status
and whether the infertility factor was male or female were not predictors
of a couple's attitudes.
相似文献
89.
Optimization of a method for deactivation of platelet-activating factor:acetylhydrolase in serum for use in in-vitro fertilization culture media 总被引:1,自引:0,他引:1
Embryos produced by in-vitro fertilization (IVF) may produce less
platelet-activating factor (PAF) than is optimal for development. It was
previously shown that supplementation of culture media with PAF results in
a significant increase in pregnancy rate. Human embryos are often cultured
in media supplemented with serum containing the enzyme PAF:acetylhydrolase
(PAF:AH; EC 3.1.1.47), which hydrolyses PAF to its inactive form, lyso-PAF.
Thus, effective supplementation of media with PAF requires inactivation of
this enzyme. In this study we examine the efficacy of the methods of PAF:AH
deactivation used for PAF supplementation of IVF culture medium. When the
effectiveness of a commonly used acid treatment protocol (pH 3.0 at room
temperature for 5 min) was examined, it was found that it was not
completely effective for the majority of sera. When synthetic PAF was added
to 18 serum samples which had been acid treated, five had 90-100% of the
original PAF remaining after 24 h (showing that the acid treatment was
effective), eight had from 10-90% of the original PAF remaining after 24 h,
and five samples had 0-10%. The extent to which PAF:AH was susceptible to
deactivation was not associated with the activity in the serum prior to
treatment, the serum oestradiol concentration, or the cause of infertility.
The period of acidification and the incubation temperature were assessed to
develop a new acid-treatment protocol (20 min acid treatment at 37 degrees
C) which was able to deactivate PAF:AH effectively in all sera (53/53)
examined. A trial was performed to assess the effect of acid treatment of
serum for 5 min at room temperature compared with the new protocol (20 min
at 37 degrees C) on IVF outcome, following PAF supplementation of IVF
culture medium. Oocyte recovery, fertilization and embryo development rates
were equivalent for both groups and approximately equal numbers of embryos
were transferred or cryopreserved. Pregnancy rates were not significantly
different (14.6 versus 20.0%) for the two treatments, with a trend towards
a higher pregnancy rate with the new acid- treatment protocol. The results
show that this new procedure for acid treatment of serum in combination
with PAF supplementation does not have detrimental effects on embryos and
their pregnancy outcome and is therefore suitable for use in IVF.
相似文献
90.
Positional cloning of the gene for X-linked retinitis pigmentosa 3: homology with the guanine-nucleotide-exchange factor RCC1 总被引:6,自引:7,他引:6
Roepman R; van Duijnhoven G; Rosenberg T; Pinckers AJ; Bleeker-Wagemakers LM; Bergen AA; Post J; Beck A; Reinhardt R; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(7):1035-1041
The gene for retinitis pigmentosa 3 (RP3), the most frequent form of X-
linked RP (XLRP), has been mapped previously to a chromosome interval of
less than 1000 kbp between the DXS1110 marker and the OTC locus at
Xp21.1-p11.4. Employing a novel technique, YAC Representation Hybridization
(YRH)', we have recently identified a small XLRP associated microdeletion
in this interval, as well as several putative exons including the 3' end of
a gene that was truncated by the deletion. cDNA library screening and
sequencing of a cosmid centromeric to the deletion has now enabled us to
identify numerous additional exons and to detect several point mutations in
patients with XLRP. The predicted gene product shows homology to RCC1, the
guanine-nucleotide- exchange factor (GEF) of the Ras-like GTPase Ran. Our
findings suggest that we have cloned the long-sought RP3 gene, and that it
may encode the GEF of a retina-specific GTP-binding protein.
相似文献