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91.
Accurate pregnancy dating is vital to obstetric management. However, first trimester fetal charts commonly used in Australia rely on data reported more than three decades ago. This study reports first trimester dating and growth charts for crown‐rump length between 5 and 14 weeks of gestation and biparietal diameter between 9 and 14 weeks of gestation on an Australia population using modern real‐time ultrasound equipment. All consenting eligible women attending a large Sydney clinic for first trimester ultrasound between March 2005 and December 2006 were recruited. Measurements were carried out to Australasian Society for Ultrasound in Medicine standard protocols. Statistical analyses were undertaken using polynomial regression models and thorough diagnostic checks made. Overall 396 eligible women consented to the study, with 268 between 9 and 14 weeks of gestation. The average participant age was 34 years (range 22–45 years), 371 and all yielded valid biometry measurements. Equations, means and 90% reference intervals for crown‐rump length measurements and biparietal diameter measurements were derived using polynomial regression models. Thorough residual and diagnostic checks were made. Once validated by others, we believe they will warrant consideration for use by Australasian Society for Ultrasound in Medicine. 相似文献
92.
Peripheral T-cell lymphomas (PTCLs) are a rare and heterogeneous group of disorders associated with a very poor prognosis.
Historically, treatment protocols have been largely based on regimens used to treat aggressive B-cell lymphomas; unfortunately,
the efficacy of these regimens has been suboptimal, with most patients experiencing relapse after initial therapy. An improved
understanding of the molecular biology, pathogenesis, and progression of these disorders has led to the development of a variety
of novel targeted agents that may improve outcomes in patients with PTCLs. The purpose of this review is to focus on these
novel agents and the various treatment approaches that are currently being evaluated in PTCLs. 相似文献
93.
AM Boot J Nauta AC Hokken-Koelega HA Pols MA de Ridder SM de Muinck Keizer-Schrama 《Archives of disease in childhood》1995,72(6):502-506
A cross sectional study assessed the bone mineral density (BMD) of 20 young adult patients who received a renal transplantation in childhood. The BMD of the lumbar spine, mainly trabecular bone, and of the total body, mainly cortical bone, were measured and expressed as an SD score. Fourteen patients (70%) had a BMD SD score of the lumbar spine below -1, of whom six patients were below -2. Fifteen patients (75%) had a BMD SD score of the total body below -1, of whom seven patients were below -2, Both trabecular and cortical bone appeared to be involved in the osteopenic process. The cumulative dose of prednisone was inversely correlated to both lumbar spine and total body BMD SD score. In a multiple regression analysis the cumulative dose of prednisone appeared to be the only factor with a significant effect on BMD SD score. Most young adult patients who had received a renal transplantation in childhood had moderate to severe osteopenia. Corticosteroid treatment played a major part in the development of osteopenia in these patients. 相似文献
94.
Outcome measurement in critical care is difficult because of the wide variety of patients treated and the diverse therapeutic options and pathways available. Individual outcome measures for critical care are available but are naturally limited to only a single aspect of performance. Most importantly, better performance in one aspect of care may compromise the standard of care in another. A global measure of performance would be helpful. For the year 1999-2000, the five hospitals in the East Anglian Critical Care Network provided data on capacity, workload and performance. The data was transformed and displayed graphically on a radar chart so that the area of the polygon within the radar chart was proportional to each unit's overall performance. The results from the five hospitals suggest that there is little overall difference in the units' global performance but the graphical representation highlighted some individual deficiencies. Graphical analysis of complex processes such as critical care delivery may facilitate performance assessment, providing that the measures chosen, weightings assigned and scales used are standardised with care. 相似文献
95.
O'Leary C Feighery C Feighery A Quane K Shanahan F Molloy M Cronin CC 《Irish journal of medical science》2002,171(3):145-147
Background
Osteoporosis frequently complicates coeliac disease but most studies focus on symptomatic patients at the time of diagnosis. Screening tests have revealed that many individuals with coeliac disease have mild, atypical, or absent symptoms. 相似文献96.
Fox NC Jenkins R Leary SM Stevenson VL Losseff NA Crum WR Harvey RJ Rossor MN Miller DH Thompson AJ 《Neurology》2000,54(4):807-812
OBJECTIVE: To assess the potential of registered volumetric MRI in measuring rates of atrophy in MS. BACKGROUND: Pathologic and imaging studies suggest that the development of permanent neurologic impairment in MS is associated with progressive brain and spinal cord atrophy. Atrophy has been suggested as a potential marker of disease progression. Conventional atrophy measurements requiring manual outlining are time-consuming and subject to reproducibility problems. Registration of serial MRI may offer a useful alternative in that cerebral losses may be measured directly from automated subtraction of brain volumes. METHODS: Twenty-six patients with MS and 26 age- and gender-matched controls had two volumetric brain MR studies 1 year apart. Baseline brain and ventricular volumes were measured using semiautomated techniques, and follow-up scans were registered to baseline. Rates of cerebral atrophy were calculated directly from the registered scans. RESULTS: Baseline brain volumes in the MS group were smaller (mean difference 78 mL [95% CI 13 to 143; p = 0.02]) and ventricular volumes greater (mean difference 12 mL [95% CI 6 to 18; p < 0.001]) than controls. The rate of cerebral atrophy in the MS group (0.8% per year) was over twice that of controls (0.3%), and the rate of ventricular enlargement was five times greater than the controls (1.6 versus 0.3 mL/year). CONCLUSION: Progressive cerebral atrophy is an important feature of MS. Registration-based measurements are sensitive and reproducible, allowing progressive atrophy to be detected within 1 year and may have potential as a marker of progression in monitoring therapeutic trials. 相似文献
97.
Obesity in children may cause overt clinical disease in childhood. The complex endocrine and metabolic changes of obesity and insulin resistance in adolescents result in hyperinsulinemia, dyslipidemia, hypertension, steatohepatitis, glucose intolerance, type 2 diabetes, acanthosis nigricans and ovarian hyperandrogenemia, commonly known as polycystic ovarian syndrome (PCOS). Type 2 diabetes and PCOS in adolescents are new endocrine diseases in this age group that require unique approaches to diagnosis and treatment. The direct correlation between duration of disease and control of the disease, and subsequent long term complications of these two diseases, predict serious morbidity in young adult life for the affected adolescents. Pediatricians have an important role in the prevention, diagnosis and treatment of obesity, insulin resistance syndrome, type 2 diabetes and PCOS. 相似文献
98.
Gene therapy-mediated expression by tumor cells of the angiogenesis inhibitor flk-1 results in inhibition of neuroblastoma growth in vivo 总被引:3,自引:0,他引:3
BACKGROUND/PURPOSE: Preventing tumors from forming new blood vessels appears to be an effective new anticancer approach. Antiangiogenic therapy usually is cytostatic, however, and, therefore, long-term angiogenesis inhibition is likely to be required. The objective of this study was to determine if sustained gene therapy-mediated expression of these agents from tumor cells could restrict tumor growth in vivo. METHODS: Two replication-defective retroviral vectors were made, one encoding both the soluble, truncated vascular endothelial growth factor receptor (VEGF-R2), flk-1, together with green fluorescent protein (GFP), and the other encoding GFP alone. These vectors were then used to transduce murine neuroblastoma cells (NXS2). Stable, high expression of the flk-1 transgene was confirmed in the former population of cells by Western analysis. Flk-1 protein was isolated from cell culture supernatants and tested in human umbilical vein endothelial cell (HUVEC) proliferation and migration assays to confirm that functional protein was being made. Finally, in vivo activity was assessed by injecting 10(6) tumor cells subcutaneously into SCID mice and monitoring subsequent tumor growth. RESULTS: Purified flk-1 (0.1 micromol/L) was able to inhibit basic fibroblast growth factor (bFGF) stimulated HUVEC proliferation by 44% and VEGF-stimulated migration by 30%. In vitro growth rates for the transduced cell lines were similar to the unmodified cell line. In vivo, however, after 23 days, tumors from flk-1 expressing neuroblastoma cells were less than 33% the average volume of tumors from cells expressing only the GFP transgene (mean volume, 1.9 cm(3) v 5.8 cm(3), P<.001). GFP expression alone had no effect on tumor growth when compared with unmodified tumor cells. CONCLUSIONS: Engineered expression of flk-1, a competitive inhibitor of VEGF, by tumor cells results in the production of an inhibitor of endothelial cell proliferation and migration that greatly restricts the growth of the tumor cells in vivo. Gene therapy-mediated delivery of angiogenesis inhibitors may provide an alternative approach to treating refractory tumors such as neuroblastoma. 相似文献
99.
Investigation of loss of heterozygosity at specific loci on chromosomes 3p, 6q, 11p, 17p and 17q in ovarian cancer 总被引:1,自引:0,他引:1
J.A. Leary C.P. Doris E.M. Boltz C.R.S. Houghton R.F. Kefford & M.L. Friedlander 《International journal of gynecological cancer》1993,3(5):293-298
In an attempt to further define the genetic events in the pathogenesis and progression of human ovarian cancer, an analysis of constitutional and ovarian carcinoma DNA samples revealed loss of heterozygosity (LOH) at specific loci on chromosomes 3p (38%), 6q (23%), 11p (33%), 17p (82%) and 17q (62%). In contrast, LOH was not observed in benign or borderline tumors. No significant association could be demonstrated between LOH at the loci studied and tumor stage, histologic subtype, grade or patient outcome. Further analyses of large tumor panels are now required to determine the relationship between LOH at these loci and the clinicopathological behavior of ovarian tumors. 相似文献
100.
M Cole L Parker AW Craft S Bell G Dale AC McGill JA Seviour J Smith 《Archives of disease in childhood》1993,68(3):376-378
The relationship between homovanillic acid (HVA), vanillylmandelic acid (VMA), and creatinine in the urine of 6 month old babies has been studied and reference ranges in the form of centiles constructed for HVA and VMA against creatinine. Over 10,000 urine samples were collected from babies in four health districts in the north of England. HVA and VMA concentration, either independently or when divided by creatinine concentration, were dependent upon the absolute concentration of creatinine in the sample. After adjustment for creatinine significant differences in the mean concentration of HVA were found between sexes. No such differences were found for VMA. HVA and VMA were also found to be age dependent. Centiles were constructed using a procedure which makes no distributional assumptions about the data. The net effect of utilising these centiles was to increase the predictive value of a positive screening test from 20% to 40% without any increase in the false negative rate. 相似文献