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51.
Several genetic factors have been found to be associated with recurrent pregnancy loss (RPL). However, not many attempts have been made to associate the mitochondrial DNA (mtDNA) variations with RPL. Therefore, we have analyzed the complete mtDNA of 100 women with RPL and 12 aborted fetal tissues. Our analysis revealed a total of 681 variations, most of which were in NADH Dehydrogenase (ND) genes that encode mitochondrial enzyme Complex I. Presence of T4216C variation (ND1 gene) in 9% of the RPL women and several pathogenic, and novel mutations suggest the role of mtDNA variations in RPL.  相似文献   
52.

Background:

International guidelines for the management of nonvariceal upper gastrointestinal bleeding have not been widely adopted in clinical practice. We sought to determine whether a national, multifaceted intervention could improve adherence to guidelines, especially for patients at high risk of nonvariceal upper gastrointestinal bleeding.

Methods:

In this randomized trial, we stratified hospitals by region and size and allocated sites to either the control or experimental group. Health care workers in the experimental group were given published guidelines, generic algorithms, stratification scoring systems and written reminders and attended multidisciplinary guideline education groups and case-based workshops. These interventions were implemented over a 12-month period after randomization, with performance feedback and benchmarking. The primary outcome of adherence rates to key guidelines in endoscopic and pharmacologic management, determined by chart review, was adjusted according to site characteristics and possible within-site dependencies. We also report the rates of adherence to other recommendations.

Results:

Forty-three sites were randomized to the experimental (n = 21) or control (n = 22) groups. In our primary analysis, we compared patients before (experimental group: n = 402 patients; control group: n = 424 patients) and after (experimental group: n = 361 patients; control group: n = 389 patients) intervention. Patient-level analysis revealed no significant difference in adherence rates to the guidelines after the intervention (experimental group: 9.8%; control group: 4.8%; p = 0.99) after adjustment for the rate of adherence before the intervention (experimental group: 13.2%; control group: 7.1%). The adherence rates to other guidelines were similar and decreased over time, varying between 5% and 93%.

Interpretation:

This national knowledge translation–based trial suggests poor adherence to guidelines on nonvariceal upper gastrointestinal bleeding. Adherence was not improved by an educational intervention, which highlights both the complexity and poor predictability of attempting to alter the behaviour of health care providers (Trial registration: ClinicalTrials.gov, no. MCT-88113).The care of patients with nonvariceal upper gastrointestinal bleeding has evolved dramatically over the past 10 years, with international consensus recommendations being issued in 2003.1 National benchmarking initiatives2,3 suggest that widespread variations in practice persist,4,5 with poor adherence to published recommendations.6 In this randomized knowledge-translation trial, we aimed to assess the effectiveness of a nation-wide active strategy to improve adoption of evidence-based consensus recommendations on nonvariceal upper gastrointestinal bleeding.  相似文献   
53.
In this study, silk fibroin nanofibrous scaffolds were developed to investigate the attachment and proliferation of primary human meniscal cells. Silk fibroin (SF)–polyvinyl alcohol (PVA) blended electrospun nanofibrous scaffolds with different blend ratios (2:1, 3:1, and 4:1) were prepared. Morphology of the scaffolds was characterized using atomic force microscopy (AFM). The hybrid nanofibrous mats were crosslinked using 25 % (v/v) glutaraldehyde vapor. In degradation study, the crosslinked nanofiber showed slow degradation of 20 % on weight after 35 days of incubation in simulated body fluid (SBF). The scaffolds were characterized with suitable techniques for its functional groups, porosity, and swelling ratio. Among the nanofibers, 3:1 SF:PVA blend showed uniform morphology and fiber diameter. The blended scaffolds had fluid uptake and swelling ratio of 80 % and 458 ± 21 %, respectively. Primary meniscal cells isolated from surgical debris after meniscectomy were subcultured and seeded onto these hybrid nanofibrous scaffolds. Meniscal cell attachment studies confirmed that 3:1 SF:PVA nanofibrous scaffolds supported better cell attachment and growth. The DNA and collagen content increased significantly with 3:1 SF:PVA. These results clearly indicate that a blend of SF:PVA at 3:1 ratio is suitable for meniscus cell proliferation when compared to pure SF-PVA nanofibers.  相似文献   
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BACKGROUND: Alveolar soft part sarcoma (ASPS) is a rare soft tissue tumor. It has characteristic histomorphology, with typical ultrastructural features demonstrating unique crystalloids. It occurs predominantly in adolescents and young adults, in whom the most common location is within the fascial planes of skeletal muscle of the lower extremity. CASE: We present fine needle aspiration biopsy (FNAB) findings along with histopathologic features and ultrastructural appearance of a large gluteal mass in a 29-year-old female. FNAB cytology smears showed single and small groups of polyhedral malignant cells with granular cytoplasm, anisokaryosis and prominent nucleoli. The delicate cytoplasm had a tendency to rupture, with the presence of many bare nuclei. The characteristic crystals were observed in Papanicolaou-stained smears within the cytoplasm and in the background near the tumor cells. This consolidated the radiologic suspicion of ASPS and facilitated the application of relevant ancillary tests. Biopsy of the mass showed the characteristic histologic pattern. Electron microscopy confirmed the diagnosis with demonstration of membrane-bound, rhomboid crystalloids with a latticelike ultrastructure. CONCLUSION: Detection of characteristic crystalloids in Papanicolaou-stained FNAB smears facilitated a proper evaluation and correct diagnosis of ASPS.  相似文献   
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Mucor rouxii CFR-G15, a locally isolated phycomycetous fungus, on cultivation at room temperature produced more than 30% (w/w) lipid in their dry cell weight, in which 14.2% accounted to be GLA content of the total fatty acids. It was observed that when incubation temperature lowered at 14°C, GLA content of the mycelium increased significantly (P<0.05) from 14.2% to 21.97%. In order to optimize the cultural conditions for high biomass and lipid production with high GLA content, the fungus was grown in association of two different temperatures and supply of additional glucose in culture medium. Maximum lipid and GLA were obtained 23.56 and 19.5% respectively, when the culture was grown at 28°C for four days and followed by addition of glucose (5%), and lowered the incubation temperature to 14°C for another four days. The presence of GLA in the oil obtained from M. rouxii CFR-G15 was confirmed by the gas chromatography-mass spectrometry. Gamma linolenic acid (GLA, n-6) is gaining importance in pharmaceutical and nutraceutical industries because of clinical evidence demonstrated that it has various beneficial effects in human health. In this paper temperature played a major role in enhancing the GLA content which has been described.  相似文献   
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Although the incidence of cancer rises with age, tumor growth is often slowed in older hosts. The B16/F10 melanoma cell line is commonly used in murine models of age-related tumor growth suppression. We wished to determine if the growth pattern and gene expression of B16/10 tumors grown in aged mice could be simulated in 3D collagen matrices derived from aged mice. Outcome measures were tumor size in vitro and gene expression of the key growth regulatory molecules: growth hormone receptor (GHR), IL-10Rβ, IL-4Rα, and IL-6. B16/F10 tumors were grown in 20–25-mo-old C57/BL6 male mice. Tumor sizes ranged from 30 to 4,910 mg in vivo. Tumors from a subset of mice were removed after euthanasia, and equivalent amounts of each tumor were placed in aged 3D collagen and grown for 5 d. Tumor sizes in aged 3D collagen correlated highly with their original tumor size in vivo. Gene expression changes noted in vivo were also maintained during tumor growth in aged 3D collagen in vitro. The relative expression of GHR was increased, IL-10Rβ was unchanged, and IL-4Rα and IL-6 were decreased in the larger tumors relative to the smaller tumors in vitro, in a pattern similar to that noted in vivo. We propose that 3D matrices from aged mice provide an in vitro model of tumor growth that correlates highly with tumor size and expression of key regulatory molecules in vivo.  相似文献   
60.
Dandy–Walker malformation (DWM) is a rare intracranial congenital abnormality that affects the cerebellum and some of its components; particularly cerebellar vermis, fourth ventricle and is characterized by an enlarged posterior fossa. Although there is an extensive list of signs attributed to DWM, final diagnosis is solely dependent on imaging techniques as there are no signs that are characteristic of DWM. This article reports a case with DWM who was diagnosed by magnetic resonance imaging.  相似文献   
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