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排序方式: 共有390条查询结果,搜索用时 15 毫秒
381.
S Fang J McLaughlin J Fang J Huang I Autti‐Rämö Å Fagerlund SW Jacobson LK Robinson HE Hoyme SN Mattson E Riley F Zhou R Ward ES Moore T Foroud 《Orthodontics & craniofacial research》2008,11(3):162-171
OBJECTIVES: Use three-dimensional (3D) facial laser scanned images from children with fetal alcohol syndrome (FAS) and controls to develop an automated diagnosis technique that can reliably and accurately identify individuals prenatally exposed to alcohol. METHODS: A detailed dysmorphology evaluation, history of prenatal alcohol exposure, and 3D facial laser scans were obtained from 149 individuals (86 FAS; 63 Control) recruited from two study sites (Cape Town, South Africa and Helsinki, Finland). Computer graphics, machine learning, and pattern recognition techniques were used to automatically identify a set of facial features that best discriminated individuals with FAS from controls in each sample. RESULTS: An automated feature detection and analysis technique was developed and applied to the two study populations. A unique set of facial regions and features were identified for each population that accurately discriminated FAS and control faces without any human intervention. CONCLUSION: Our results demonstrate that computer algorithms can be used to automatically detect facial features that can discriminate FAS and control faces. 相似文献
382.
OBJECTIVE: The aim of this study is to determine whether gingival crevicular fluid (GCF) dipeptidyl peptidase (DPP) II or IV levels, total activity (TA) and concentration (EC), predict progressive attachment loss (AL). SUBJECTS AND METHODS: Seventy five patients with moderate periodontitis were recruited. GCF was first collected from 16 molar and premolar mesiobuccal sites and then probing attachment level (PAL) and probing pocket depth (PPD) were measured with an electronic probe. Finally, gingival index, gingival bleeding and plaque indices were scored. Patients were given basic periodontal treatment prior to baseline after which the above procedures were repeated. Patients were seen 3 monthly for 2 years and the procedures were repeated. Carefully localised radiographs were taken of the test teeth annually. RESULTS: One hundred and twenty AL sites, 88 rapid AL (RAL) and 32 gradual AL (GrAL), in 48 patients were detected. DPP It and IV levels (TA and EC) at RAL sites were significantly higher (P ≤ 0.0001) than paired control sites at the attachment loss time (ALT) and prediction time (PT). Mean levels over the study period of both proteases (TA and EC) at GrAL sites were significantly higher (P≤ 0.0001) than paired control sites. The GCF levels of DPP IV were always slightly higher than those of DPP II. Critical values (CV) of 5 μU per 30 s (TA) and 25 μU μPI-1 (EC) for both proteases showed high sensitivity and specificity values for TA and EC and these were the same at both ALT and PT. The positive predictive values were slightly higher for DPP II. Mean site DPP II and IV levels (TA and EC) in intra-patient comparisons were significantly higher (P ≤ 0.0001) at RAL and GrAL sites than non-attachment loss (NAL) sites in AL patients and mean patient levels were significantly higher (P ≤ 0.0001) in AL patients than NAL patients in inter-patient comparisons. CONCLUSIONS: These results indicate that both GCF DPP II and IV may be predictors of periodontal attachment loss. 相似文献
383.
Bryan C Cannon Susan W Denfield Richard A Friedman Arnold L Fenrich W Jeffrey Dreyer Jeffrey A Towbin Naomi J Kertesz 《The Journal of heart and lung transplantation》2004,23(1):67-71
BACKGROUND: Few data are available regarding pacemaker implantation after pediatric orthotopic heart transplantation. The purpose of this study was to assess the incidence, indications and associations with regard to pacemaker placement in children who have undergone orthotopic heart transplantation. METHODS: We performed a retrospective study of all patients undergoing orthotopic heart transplantation at our institution from October 1984 to March 2001. Data obtained included demographics, indications for pacemaker, presence of transplant coronary artery disease and long-term follow-up. Patients were divided into: Group 1, patients requiring a pacemaker within 3 months of transplantation; and Group 2, patients requiring a pacemaker beyond 3 months. RESULTS: Pacemakers were required in 7 of 106 (6.6%) transplant recipients. Pacing indications for patients in Group 1 (n = 2) were persistent bradycardia with pause-related ventricular arrhythmia and atrial flutter with resultant sinus pauses of up to 4 seconds. In Group 2 patients (n = 5), indications for pacing were high-grade atrioventricular (AV) block in 1 patient and episodic sinus pauses up to 3.3 seconds associated with syncope/dizziness in the remaining 4 patients. All patients in Group 2 had transplant coronary disease diagnosed within 1 year of pacemaker implantation. All had resolution of symptoms and no complications after implantation. CONCLUSIONS: Pacemakers are infrequently required after cardiac transplantation in children. Despite not meeting classic symptomatic sinus bradycardia criteria, pacemaker placement should be considered post-transplantation in patients with episodic sinus pauses and dizziness or syncope. Patients who present with the aforementioned symptoms or high-grade AV block should be evaluated closely for the presence or development of transplant coronary artery disease, as it may be their first symptom. 相似文献
384.
Accuracy and feasibility of point-of-care and continuous blood glucose analysis in critically ill ICU patients 总被引:1,自引:0,他引:1
Corstjens AM Ligtenberg JJ van der Horst IC Spanjersberg R Lind JS Tulleken JE Meertens JH Zijlstra JG 《Critical care (London, England)》2006,10(5):R135-7
Introduction
To obtain strict glucose regulation, an accurate and feasible bedside glucometry method is essential. We evaluated three different types of point-of-care glucometry in seriously ill intensive care unit (ICU) patients. The study was performed as a single-centre, prospective, observational study in a 12-bed medical ICU of a university hospital. 相似文献385.
386.
Autism spectrum disorders (ASDs) are a heterogeneous group of neurodevelopmental disorders affecting social communication, language and behavior. The underlying cause(s) in a given individual is often elusive, with the exception of clinically recognizable genetic syndromes with readily available molecular diagnosis, such as fragile X syndrome. Clinical geneticists approach patients with ASDs by ruling out known genetic and genomic syndromes, leaving more than 80% of families without a definitive diagnosis and an uncertain risk of recurrence. Advances in microarray technology and next‐generation sequencing are revealing rare variants in genes with important roles in synapse formation, function and maintenance. This review will focus on the clinical approach to ASDs, given the current state of knowledge about their complex genetic architecture. 相似文献
387.
388.
FH Saner M Heuer M Meyer A Canbay GC Sotiropoulos A Radtke J Treckmann S Beckebaum C Dohna-Schwake SW Oldedamink A Paul 《European journal of medical research》2009,14(12):541-546
Congestive heart failure as a cause of acute liver failure is rarely documented with only a few cases.Although the pathophysiology is poorly understood, there is rising evidence, that low cardiac output with consecutive reduction in hepatic blood flow is a main causing factor, rather than hypotension. In the setting of acute liver failure due to congestive heart failure, clinical signs of the latter can be absent, which requires an appropriate diagnostic approach.As a reference center for acute liver failure and liver transplantation we recorded from May 2003 to December 2007 202 admissions with the primary diagnoses acute liver failure. 13/202 was due to congestive heart failure, which was associated with a mortality rate of 54%. Leading cause of death was the underlying heart failure. Asparagine transaminase (AST), bilirubin, and international normalized ratio (INR) did not differ significantly in surviving and deceased patients at admission. Despite both groups had signs of cardiogenic shock, the cardiac index (CI) was significantly higher in the survival group on admission as compared with non-survivors (2.1 L/min/m2 vs. 1.6 L/min/m2, p = 0.04). Central venous - and pulmonary wedge pressure did not differ significantly. Remarkable improvement of liver function was recorded in the group, who recovered from cardiogenic shock.In conclusion, patients with acute liver failure require an appropriate diagnostic approach. Congestive heart failure should always be considered as a possible cause of acute liver failure. 相似文献
389.
Johnson EJ; Scherer SW; Osborne L; Tsui LC; Oscier D; Mould S; Cotter FE 《Blood》1996,87(9):3579-3586
Chromosome 7 translocations, deletions, or monosomy are associated with myelodysplasia (MDS) and acute myeloid leukemia both in children and adults. These chromosomal anomalies represent one of the most common cytogenetic abnormalities associated with these diseases and usually herald a poor prognosis. In this study two cosmid DNA probes that mapped to 7q22.1 and were known to be separated by approximately 500 kb were identified to flank the proximal inversion breakpoint in a patient carrying a constitutional inversion (7q22.1-34) associated with MDS. A yeast artificial chromosome (YAC) clone that encompassed the two cosmids was identified and shown to span the breakpoint. Fluorescence in situ hybridization was then used to analyze six additional patients with myelodysplasia and chromosomal rearrangements of the 7q22 region (three patients had translocations and three carried deletions). The breakpoint in one of the patients was found to be contained within the same YAC clone that spanned the inversion breakpoint. Moreover, this same interval was determined to be absent in all three patients with chromosomal deletions. These results suggest that this segment of DNA on chromosome 7q22.1 may contain specific gene(s) that have a significant role in myeloid malignancies. 相似文献
390.