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51.
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
52.
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
53.
54.
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
55.
The t(X;1)(p11.2;q21.2) translocation in papillary renal cell carcinoma fuses a novel gene PRCC to the TFE3 transcription factor gene 总被引:4,自引:2,他引:4
56.
This study explored the use of non-radioactive 2-deoxy glucose (2DG)-labeled magnetonanoparticles (MNP) and magnetic resonance imaging (MRI) to detect functional activity during rest, peripheral stimulation, and epileptic seizures, in animal models. Non-radioactive 2DG was covalently attached to magnetonanoparticles composed of iron oxide and dextran and intravenous (tail) injections were performed. 2DG-MNP was injected in resting and stimulated na?ve rodents and the subsequent MRI was compared to published (14)C-2DG autoradiography data. Reproducibility and statistical significance was established in one studied model. Negative contrast enhancement (NCE) in acute seizures and chronic models of epilepsy were investigated. MRI NCE due to 2DG-MNP particles was compared to that of plain (unconjugated) MNP in one animal. NCE due to 2DG-MNP particles at 3?T, which is approved for human use, was also investigated. Histology showed presence of MNP (following intravenous injection) in the brain tissues of resting na?ve animal. 2DG-MNP intraparenchymal uptake was visible on MRI and histology. The locations of NCE agreed with published results of 2DG autoradiography in resting and stimulated animals and epileptic rats. Localization of epileptogenicity was confirmed by subsequent depth-electrode EEG (iEEG). Non-radioactive 2DG-MNP can cross the blood-brain barrier (BBB) and may accurately localize areas of increased activity. Although, this proof-of-principle study involves only a limited number of animals, and much more research and quantification are necessary to demonstrate that 2DG-MNP, or MNPs conjugated with other ligands, could eventually be used to image localized cerebral function with MRI in humans, this MNP-MRI approach is potentially applicable to the use of many bioactive molecules as ligands for imaging normal and abnormal localized cerebral functions. 相似文献
57.
Omar Hayani Lyall AJ Higginson Baldwin Toye Ian G Burwash 《The Canadian journal of cardiology》2009,25(4):e130-e132
Infective endocarditis caused by zoonotic microorganisms is an uncommon clinical entity. A 55-year-old man was diagnosed with endocarditis due to Capnocytophaga canimorsus, a commensal bacterium contained in the saliva of dogs, that involved the aortic and tricuspid valves and was complicated by a para-aortic valve abscess and aorta-to-right atrial fistula. The patient was successfully treated with antibiotic therapy and surgical intervention. C canimorsus endocarditis should be considered in patients with culture-negative endocarditis, particularly in immunosuppressed, asplenic or alcoholic individuals who have recently suffered a dog bite or have had close contact with dogs. 相似文献
58.
59.
After the introduction of the colposcope for the examination of children suspected of being sexually abused in Leeds, a study was undertaken to describe the findings in detail. A total of 109 consecutive prepubertal girls, mean age 70.4 months were assessed including colposcopic genital and anal examination, and peer group review of reports and photographs. Fifty nine children had signs consistent with blunt force penetrating trauma (hymenal transection/major notch, scar, or hymenal attenuation). Transections were encountered most commonly at 6 o'clock (directly posterior). In 46 the hymenal orifice was gaping with thigh abduction only and in 47 the hymenal orifice transverse diameter was greater than 4 mm on labial separation. Overall, physical findings were commonly present and in only two cases were no signs recorded. Non-specific and frequent findings included patterns of labial and introital reddening. Supportive hymenal signs including swelling, rounding of edge, thickening, distortion, and loss of symmetry were common. Labial fusion was present in 20. Urethral dilatation with labial separation was noted in 14. Physical findings including normality are consistent with abuse and even minor anogenital signs as well as negative findings should be documented. Colposcopy and photography are valuable tools in peer review, teaching, and case management. 相似文献
60.
AJ Blethyn HR Jenkins R Roberts K Verrier Jones 《Archives of disease in childhood》1995,73(6):534-535
Little objective evidence has been published to support the claim that constipation is an important contributory factor in recurrent urinary tract infection (UTI) in childhood. Using a radiological scoring system, two observers assessed faecal loading from abdominal radiographs of children with proved UTIs. There was a significant increase in the degree of faecal loading in children with UTI when compared with controls (r = 0.237). This difference was mainly accounted for by girls with recurrent (greater than five) UTIs. This study confirms an association between recurrent UTI and faecal loading. Further studies are needed to establish if there is a causal relationship and benefits from treatment. 相似文献