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101.
Objective  We investigated the application of high-resolution microarray-based comparative genomic hybridisation (array CGH) on a fetus showing increased nuchal translucency (NT).
Design  Case study.
Setting  Tertiary referral obstetrics unit.
Sample  Pregnant woman attended the antenatal clinic.
Methods  Conventional karyotyping and genetic test was carried out for the alpha-globin gene. High-resolution array CGH using the high-density 244K Agilent microarray was performed on fetal blood sample by cordocentesis to investigate the possibility of any genomic imbalance.
Main outcome measures  Detection of chromosomal abnormality.
Results  Karyotyping analysis showed 46,XY. Molecular genetic diagnosis confirms the fetus has Hb-H constant spring disease but cannot explain the increased NT to 3.2 mm. Array CGH analysis discovered a 1.32-Mb microdeletion on chromosome 16p13.11. Deletion at 16p13.11 has been implicated to predispose to autism and/or mental retardation. Baby was delivered at 40 weeks of gestation, and follow up was carried out at 3 months of age without sign of mental retardation/developmental delay.
Conclusions  This case study demonstrated that array CGH can accurately calibrate the size and identify de novo interstitial chromosome imbalances. However, the presence of chromosome copy variants with unknown clinical significance currently limits its wider scale application in prenatal diagnosis and needs further investigations.  相似文献   
102.
Effects of elbow positioning on grip strength and its between-day reliability of measurement were tested bilaterally in 30 healthy adults. Grip strength was measured twice with a Jamar dynamometer at 0°, 30°, 60°, 90° and 120° of elbow flexion one week apart. Intraclass correlation coefficient model(1,1) was > 0.987 for each test, and limits of agreement reveal narrow ranges of the 95% confidence intervals for each test, which reflect good between-day reliability for these measurements in both absolute and relative terms. Grip strength at 120° was significantly lower than all other positions on both sides (p < 0.001), whereas the grip strength at 90° was highest among all positions tested. The grip strengths at 0°, 30° and 60° were, in general, 0.5-3% lower than the measurements taken at 90° of elbow flexion, but the differences were not statistically significant. These findings suggest that between-day comparison of grip strength is valid and reproducible in the same testing position, and 120° of elbow flexion is not a desirable position for grip strengthening exercise. The differences in grip strength can be explained by the length-tension relationship and the clinical implications for these findings are discussed.  相似文献   
103.
104.
105.
A prospectively controlled pilot study of 100 patients undergoing an invasive radiological procedure was undertaken to test patients' acceptance of risk disclosure and whether this increases anxiety and rate of procedure cancellation. Two sheets with differing amounts of information on adverse outcome were randomly allocated and patients provided a graded response to statements following the procedure. Eighty-one completed questionnaires were received (brief sheet n= 40; long sheet n= 41). There were 19 non-compliers with main causes either due to lack of interest or problems such as language difficulties, visual impairment and dementia. There were no significant differences between the two groups with respect to subjective anxiety caused by the information or risk of procedure cancellation. This preliminary work has shown that information sheets are well accepted and provide a simple, standardized format for risk disclosure.  相似文献   
106.
It would appear that it has become almost common practice to regard arachidonic acid (AA) as the sole precursor of eicosanoids. The fact that both dihomogamma-linolenic acid (DGLA) and eicosapentaenoic acid (EPA) give rise to distinct families of eicosanoids is commonly almost completely ignored. Elevated tissue levels of AA eicosanoids have been found in and have been implicated in the etiology of a number of diseases. Drugs which selectively block AA mobilization or its eicosanoid metabolism have therefore been developed for therapeutic use in these conditions. The fact that such drugs will also simultaneously block the eicosanoid metabolism from DGLA as well as from EPA is also commonly ignored. It is suggested that the profoundly adverse side-effects displayed by some of these drugs, resulting in some instances in their withdrawal from use, could be the direct result of their concomitant action of interfering with the eicosanoid metabolism of DGLA and EPA. It is further suggested that, before the interactions between the eicosanoids derived from AA and those derived from DGLA and EPA are understood, the use of drugs for the manipulation of AA eicosanoid metabolism in isolation, could be hazardous. This implies that all such drugs currently in use are to be regarded as experimental and provisionally toxic in terms of their effects on the whole system of eicosanoid metabolism. Thus even drugs which have been passed by the FDA and similar Drug Control Councils require total re-evaluation especially in view of the fact that the non-steroidal anti-inflammatory drugs are often prescribed for chronic conditions which require therapy for several years.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
107.
108.
Primitive neuroectodermal tumours of the cerebrum   总被引:1,自引:1,他引:0  
Summary Eighteen cases of cerebral tumour composed partly or totally of primitive embryonal cells are reported. These lesions comprise 2.8% of all primary cerebral hemisphere tumours in the histopathology files of The Royal Marsden Hospital between 1971 and 1980 inclusive. Most exhibited some degree of differentiation towards neuronal or glial elements and, as more than one type of differentiation was often present in the same lesion, we agree with others that the term primitive neuroectodermal tumour (PNET) is more appropriate to describe these lesions than terms based on histogenesis. The extent of the primitive component varied, but usually accounted for more than 80% of the tumour. Although the tumours bear some similarities to posterior fossa medulloblastomas, they exhibit important differences in histology, immunohistology, natural history and response to treatment. Nearly all PNETs examined expressed some glial fibrillary acidic (GFAP) both in primitive areas and zones of astrocytic differentiation. GFAP staining may thus be of value in distinguishing PNETs from undifferentiated non-neurogenic tumours. Of 14 patients referred for radiotherapy, the survival rate at 3 years was 29% (\414) and 5 years 25% (\312). Patients with tumours in which at least 90% of the tissue was undifferentiated exhibited an extremely poor prognosis with none of 9 patients still alive at 3 years in contrast to 3 of 5 patients (60%) with tumours showing less than 90% undifferentiation. Radical tumour removal, where feasible, followed by irradiation of the whole cerebrospinal axis is recommended. Adjuvant chemotherapy with such agents as CCNU and Vincristine may be of value: the 3 long term survivors in the present series (7–11 years), including one who presented disseminated intracranial disease, received such adjuvant treatment.  相似文献   
109.
c-kit expression in human megakaryoblastic leukemia cell lines   总被引:1,自引:0,他引:1  
Hu  ZB; Ma  W; Uphoff  CC; Quentmeier  H; Drexler  HG 《Blood》1994,83(8):2133-2144
  相似文献   
110.
Meniscal flounce MR imaging   总被引:2,自引:0,他引:2  
Yu  JS; Cosgarea  AJ; Kaeding  CC; Wilson  D 《Radiology》1997,203(2):513
  相似文献   
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