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21.
BACKGROUND: Arterial mechanical parameters are modified in women with polycystic ovary syndrome (PCOS), before and during pregnancy. This study tested the hypothesis that aortic mechanics and endothelial function are modified in the mifepristone-treated rat model of PCOS. METHODS: Female rats injected daily with mifepristone or vehicle for 7-9 days were assessed by ultrasound to allow estimation of aortic stiffness index and compliance. The influence of acetylcholine (ACh) and sodium nitroprusside (SNP) on dissected phenylephrine-contracted aortic rings was assessed. RESULTS: Aortic compliance was reduced by 67% in mifepristone-treated rats versus controls (P<0.05), while stiffness index was increased 2.3-fold (P<0.02). ACh-induced dilation was less in aortic rings from mifepristone-treated rats (P=0.022) and was less sensitive to the nitric oxide (NO) synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) (P<0.001), while SNP-induced dilation was greater (P=0.001). CONCLUSIONS: Aortic mechanics in vivo and endothelial function in vitro were consistently perturbed in mifepristone-treated rats. Aortic ring behaviour suggested that NO release was depressed or degradation elevated, with a compensatory increase in NO sensitivity and/or activation of a non-NO-mediated relaxation mechanism. The mifepristone-treated rat is a valid model for investigation of the vascular deficits seen in PCOS.  相似文献   
22.
Objective: The aim of the study was to assess whether vaginal administration of misoprostol before copper intrauterine device (IUD) insertion increased the success of the procedure among parous women with previous insertion failure.

Methods: A single-centre, parallel-group, double-blind, placebo-controlled, randomised clinical trial was conducted at Ain Shams University Maternity Hospital, Cairo, Egypt, between October 2015 and August 2016. The study comprised 90 parous women undergoing TCu380A IUD insertion after a failed attempt. A computer-generated list of random numbers was used to assign participants to receive either misoprostol 200?μg or a placebo tablet, applied vaginally 10?h and 4?h prior to the second attempted IUD insertion, without ultrasound guidance. The primary outcome was the success of IUD insertion. Secondary outcomes were to establish the effect on insertion success of cervical dilation, cervical softening and previous mode of delivery.

Results: Forty-two women (93.3%) in the misoprostol group and 24 women (53.3%) in the placebo group had a successful IUD insertion (p?<?.001). Cervical dilation was required in 24 women in the misoprostol group and 44 women in the placebo group. Misoprostol application significantly increased insertion success in women with previous caesarean delivery (p?<?.001) but did not affect insertion success in women with previous vaginal delivery (p?=?.481).

Conclusion: Vaginal misoprostol before IUD insertion in parous women with previous insertion failure increased the rate of successful insertion, particularly in women with previous caesarean delivery.  相似文献   

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Myhre syndrome is a very rare condition described thirty years ago and related to mutations in the SMAD4 gene. It has been reported in 19 patients, including 13 males and 6 females before the recent finding of heterozygous mutations in the SMAD4 gene in 19 patients. It is characterized by mental retardation, short stature, muscle hypertrophy, limitation of joints movements, deafness, skeletal anomalies, and facial dysmorphism. Ophthalmological involvement includes hypermetropia and congenital cataract. We report here the new finding of retinal involvement including retinitis pigmentosa and maculopathy in two unrelated patients with Myhre syndrome. The patient with retinitis pigmentosa carried the p.I500T mutation in SMAD4, but no mutation was found in the patient with the maculopathy.  相似文献   
25.
Submicroscopic duplications of the genomic interval deleted in Miller-Dieker syndrome (MDS) were recently identified by array-based comparative genomic hybridization (a-CGH) studies, describing new genomic disorders in the MDS locus. These rearrangements of varying size, from 59-88 kb to 4 Mb, were non-recurrent, and appear to result from diverse molecular mechanisms. Only five patients had overlapping 17p13.3 duplications including the entire MDS critical region. We describe here a 13-year-old girl with a novel microduplication of the MDS critical region, involving the PAFAH1B1 and YWHAE genes. She presented with moderate psychomotor retardation, speech delay, behavioral problems, and bilateral cleft lip and palate, a previously unreported manifestation. Initially diagnosed as having an apparently simple terminal Xq26 deletion on standard cytogenetic analysis, she was found to have an associated terminal 4.2 Mb 17p13.3 submicroscopic duplication, identified by subtelomere FISH analysis, further characterized by high-resolution array CGH, resulting from an unbalanced X;17 translocation. Phenotypic comparison with the 5 other patients previously described, revealed common phenotypic features, such as hypotonia, mild to moderate developmental delay/mental retardation, speech abnormalities, behavioral problems, recurrent infections, relatively increase of body weight, discrete facial dysmorphism including downslanting palpebral fissures, broad midface, pointed chin, contributing to further delineate this new 17p13.3 microduplication syndrome.  相似文献   
26.
Content-based retrieval in picture archiving and communication systems   总被引:1,自引:0,他引:1  
A COntent-Based Retrieval Architecture (COBRA) for picture archiving and communication systems (PACS) is introduced. COBRA improves the diagnosis, research, and training capabilities of PACS systems by adding retrieval by content features to those systems. COBRA is an open architecture based on widely used health care and technology standards. In addition to regular PACS components, COBRA includes additional components to handle representation, storage, and content-based similarity retrieval. Within COBRA, an anatomy classification algorithm is introduced to automatically classify PACS studies based on their anatomy. Such a classification allows the use of different segmentation and image-processing algorithms for different anatomies. COBRA uses primitive retrieval criteria such as color, texture, shape, and more complex criteria including object-based spatial relations and regions of interest. A prototype content-based retrieval system for MR brain images was developed to illustrate the concepts introduced in COBRA.  相似文献   
27.
Citrus limonoids, nomilin and limonin, were used for larvicidal assay against Aedes albopictus utilizing WHO methodology. LC50s were 305.83, 176.08, and 136.07 μM for nomilin and 850.09, 600.72, and 407.09 μM for limonin after 24, 48, and 72 h, respectively. LT50 assays exhibited that Savage citrange oil was the best at all concentrations (400, 500, 600, and 700 ppm) while Fairchild and Cassa grande were the weakest oils at 400 ppm, but at 500, 600, and 700 ppm, Carrizo citrange remained at the bottom with highest LT50 values. Results exhibited that nomilin was more toxic than limonin and therefore provided a clear indication that limonoids in sample oils influenced the potential of respective oil. Out of the 10 tested citrus seed oils, Savage citrange (Citrus sinensis) comprised the maximum amount of limonin (2823.59 μg/ml) followed by grapefruit, Sacaton citrumelo, and Jaffa. When this oil (Savage citrange) was evaluated for bioassay against larvae of Ae. albopictus, it reflected complete dominance (LC50 and LT50) as compared to rest of the oils. Although Jaffa (Citrus paradisi) was found to contain nomilin and limonin, it was found less effective as compared to Savage citrange. The oils from Minneola and Chinese lime did not contain limonin and nomilin, and were therefore weak in terms of LC50 values. Presence of limonin and nomilin in plant products is therefore a significant indicator of the pest control that needs to be exploited in other plants as well.  相似文献   
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29.
Purpose : The dense nonretentive surface of zirconia implants was modified into a nanoporous surface using selective infiltration etching surface treatment. The aim of this study was to investigate the influence of such a nanoporous modified zirconia surface on the attachment of human osteoblasts. Materials and Methods : Human osteoblasts were cultured for 21 days on (i) selective infiltration etched zirconia (nanoporous surface), (ii) polished zirconia, (iii) polished titanium, or (iv) airborne particle abraded acid etched (SLA) titanium disks. After the culture period the following parameters were assessed: number of cells, the morphology of the cells, the attachment of the cells, alkaline phosphatase activity, and the level of total protein (α= 0.05). Results : Statistical analysis revealed a significantly higher cell count on the third (F = 17.4, p < 0.001) and eighth day (F = 163, p < 0.001) for nanoporous zirconia and SLA titanium surfaces compared to polished specimens. The number of cells (nanoporous zirconia 160 ± 20/mm2, SLA titanium 133 ± 15/mm2) and cell size (nanoporous zirconia 50.7 ± 3 μm, SLA titanium 42.5 ± 4 μm) were significantly higher than polished specimens. Nanoporous zirconia specimens demonstrated comparable alkaline phosphatase activity (0.0036 ± 0.0035 ng/μl) and intracellular protein content (72.7 ± 0.9 ng/μl) compared to other tested groups. Scanning electron microscopy revealed that cells attached on the polished surface using finger‐like processes, whereas on the nanoporous surface, finger‐like processes were not observed, as the cell membrane appeared to be in close proximity to the underlying surface. Conclusion : The findings of this study suggest that a nanoporous zirconia surface favors cell growth and attachment compared to a polished surface. It was proposed that a nanoporous zirconia surface may improve clinical performance of zirconia implants.  相似文献   
30.
We present a case of solitary eosinophilic granuloma in the skull of a 6-year-old Saudi boy. This osteolytic lesion has fluid-fluid level on CT and MRI. We are presenting a rare radiological finding of eosinophilic granuloma.  相似文献   
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