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1.
目的:描述胚胎种植前遗传诊断在1例携带Ⅰ型白细胞黏附缺陷病(LAD-1)携带者并完成健康妊娠夫妇中的应用。设计:病例报道。机构:大学医院生殖中心。患者:1例男女双方都是LAD-1携带者的夫妇,女方CD18基因的外显子4携带有G400A置换,男方的外显子5携带有C562T置换。干预:标准体外受精(IVF)后第3天行卵裂期活检和分裂球遗传分析以检测2处突变以及21号染色体标记物。主要观察指标:1个未罹患LAD-1婴儿的出生。结果:得到15个卵母细胞,其中10个受精。8个胚胎适宜胚胎活组织检查。  相似文献   
2.
Poly(DL-lactic acid) [DL-PLA] microcapsules containing phenobarbitone (PB) were prepared using a w/o emulsion-evaporation method. DL-PLA of three different molecular weights, 20,200, 13,300 and 5,200 were used to prepare microcapsules of nominal core: polymer (C:P) ratios of 1 : 2, 1 : 2.5, 1 : 3 and 1 : 4. The release of PB was investigated in aqueous buffer of pH 2, pH 7 and pH 9 at 37 degrees C and found to follow a square root of time dependent release mechanism. The first order and zero order release mechanisms were disproved by the lower correlation coefficient of the release data as compared to that of the t1/2 mechanism. These microcapsules showed an initial burst phase release followed by a lag phase, during which time little PB was released. This lag time was affected by the polymer molecular weight and pH of the buffer. The polymer matrix was hydrated during the lag phase and a steady state release occurred. The steady state release rate per unit specific surface area (Kh2/SSA) was found to increase exponentially with the increase in core loading of the microcapsules. However the extent of normalized release rate reduced linearly with the increase in polymer molecular weight at any particular core loading (e.g. 20 per cent or 30 per cent). Increases in the normalized steady state release rate with an increase in buffer pH could be correlated to PB solubility in the dissolution medium. PB release from these microcapsules was diffusion controlled. However, swelling and erosion also contributed to the release process.  相似文献   
3.
Poly (DL-lactic acid) [DL-PLA] microcapsules containing phenobarbitone were prepared using a W/O emulsion method. Microcapsules of nominal C : P ratio, 1 : 2 and 1 : 3 using three different molecular weight polymers, 20,500, 13,300 and 5,200 were investigated to study the effect of storage conditions on the microcapsule properties. All microcapsules were stored under desiccated condition at temperatures of 4 degrees, 20 degrees and 37 degrees C for six months. Storage temperatures of 4 degrees and 20 degrees C did not cause appreciable changes in the release rate after storage. Microcapsules stored at 37 degrees C showed an annealing effect, causing shrinkage of microcapsules, and lowering of the release rate after storage for six months. The microcapsules prepared from low molecular weight DL-PLA fused completely whilst stored at 37 degrees C and the other two high molecular DL-PLA also showed some aggregation. There were insignificant variations in the mean microcapsule diameter during storage. The phenobarbitone content of the microcapsules was also unchanged.  相似文献   
4.
Data on the effects of laser radiation on primary teeth are scarce. This study investigates the effects of exposing sound enamel, photo-initiated sound enamel, sound dentine and carious dentine of extracted primary teeth to a pulsed neodymium-yttrium aluminium garnet laser (Nd-YAG, wavelength 1.06 μm, pulse length 15μs). Each type of tissue was exposed to three fiuences. Qualitative and quantitative assessments of the irradiated areas revealed that the most marked changes were produced in carious dentine, followed in ranking order by sound dentine, photo-initiated enamel and sound enamel. Evidence of thermal damage to the hard tissues peripheral to the fibre-optic tip, and considerable inter-sample variation were found. The experimental evidence obtained in this in vitro study does not support the clinical use of pulsed laser at 1.06 μm wavelength for cutting primary enamel and dentine.  相似文献   
5.
The aim of this study was to investigate the number of emerged primary teeth at various ages from 6 to 24 months in 1347 longitudinally followed Pakistan infants sampled from four socio-economically different areas in Lahore, Pakistan; from a very poor periurban slum to a privileged upper middle class group. The emergence of the primary teeth was found to be little, or not all related to sex or to the area of living. However, in comparison with studies conducted in other continents, the Indo-Pak subcontinent population lags behind in primary teeth emergence, especially in early life. This genetic difference makes it necessary to create specific standards of primary teeth emergence for this population.  相似文献   
6.
Citrin is a mitochondrial aspartate glutamate carrier primarily expressed in the liver, heart, and kidney. We found that adult-onset type II citrullinemia is caused by mutations in the SLC25A13 gene that encodes for citrin. In this report, we describe the frequency of SLC25A13 mutations, the roles of citrin as a member of the urea cycle and as a member of the malate-aspartate shuttle, the relationship between its functions and symptoms of citrin deficiency, and therapeutic issues.  相似文献   
7.
Kidney transplantation reduces mortality in patients with end stage renal disease (ESRD). Decisions about performing kidney transplantation in the setting of a prior cancer are challenging, as cancer recurrence in the setting of immunosuppression can result in poor outcomes. For cancer of the breast, rapid advances in molecular characterization have allowed improved prognostication, which is not reflected in current guidelines. We developed a 19-question survey to determine transplant surgeons’ knowledge, practice, and attitudes regarding guidelines for kidney transplantation in women with breast cancer. Of the 129 respondents from 32 states and 14 countries, 74.8% felt that current guidelines are inadequate. Surgeons outside the United States (US) were more likely to consider transplantation in a breast cancer patient without a waiting period (p = .017). Within the US, 29.2% of surgeons in the Western region would consider transplantation without a waiting period, versus 3.6% of surgeons in the East (p = .004). Encouragingly, 90.4% of providers surveyed would consider eliminating wait-times for women with a low risk of cancer recurrence based on the accurate prediction of molecular assays. These findings support the need for new guidelines incorporating individualized recurrence risk to improve care of ESRD patients with breast cancer.  相似文献   
8.
Strategies to optimize the management of obesity-related metabolic complications after liver transplantation (LT) are needed. We examined the effect of pre-LT sleeve gastrectomy (SG), as compared to medical weight loss (MWL), on post-LT outcomes. This is a cohort study of adults (≥18 years) with medically complicated obesity who were eligible for pre-LT SG and underwent LT from January 1, 2006 to June 1, 2016. Logistic regression models evaluated the association of SG on post-LT diabetes and hypertension, defined as new-onset or progressive disease post-LT. Cox regression models evaluated the association of SG on recurrent and de novo nonalcoholic fatty liver disease (NAFLD). Among 70 LT recipients who were eligible for pre-LT SG, 14 (20%) underwent SG and 56 (80%) underwent MWL only. Mean follow-up was 5.2 years post-LT. The SG cohort sustained higher % total body weight loss at 3 years post-LT (28.9% vs. 5.4%, p < .001). In multivariable analyses, SG was associated with significantly lower risk of post-LT diabetes (OR 0.04, 95% CI 0.00–0.41, p = .01), hypertension (OR 0.15, 95% CI 0.04–0.67, p = .01), and recurrent and de novo NAFLD (HR 0.19, 95% CI 0.04–0.91, p = .04). When compared to MWL, SG resulted in sustained weight loss and significantly lower risk of diabetes, hypertension, and recurrent and de novo NAFLD post-LT.  相似文献   
9.
10.
BackgroundMeningiomas are the most common primary intracranial tumor in adults. Clinical care is currently guided by the World Health Organization (WHO) grade assigned to meningiomas, a 3-tiered grading system based on histopathology features, as well as extent of surgical resection. Clinical behavior, however, often fails to conform to the WHO grade. Additional prognostic information is needed to optimize patient management.MethodsWe evaluated whether chromosomal copy-number data improved prediction of time-to-recurrence for patients with meningioma who were treated with surgery, relative to the WHO schema. The models were developed using Cox proportional hazards, random survival forest, and gradient boosting in a discovery cohort of 527 meningioma patients and validated in 2 independent cohorts of 172 meningioma patients characterized by orthogonal genomic platforms.ResultsWe developed a 3-tiered grading scheme (Integrated Grades 1-3), which incorporated mitotic count and loss of chromosome 1p, 3p, 4, 6, 10, 14q, 18, 19, or CDKN2A. 32% of meningiomas reclassified to either a lower-risk or higher-risk Integrated Grade compared to their assigned WHO grade. The Integrated Grade more accurately identified meningioma patients at risk for recurrence, relative to the WHO grade, as determined by time-dependent area under the curve, average precision, and the Brier score.ConclusionWe propose a molecularly integrated grading scheme for meningiomas that significantly improves upon the current WHO grading system in prediction of progression-free survival. This framework can be broadly adopted by clinicians with relative ease using widely available genomic technologies and presents an advance in the care of meningioma patients.  相似文献   
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