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991.
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BACKGROUND: The echocardiographic diagnosis of apical hypertrophic cardiomyopathy (ACM) has been limited by the frequent inability to visualize the apical endocardium. We hypothesized that the use of contrast agents in patients with suspected ACM, but nondiagnostic echocardiographic studies, would allow quantitative diagnosis. METHODS: Contrast enhancement was performed in 26 patients with nondiagnostic transthoracic echocardiograms (TTEs) for the diagnosis of ACM; 6 patients with suspected ACM based on unexplained symmetric precordial T-wave inversions and increased apical tracer uptake on single-photon emission computed tomography (SPECT) scans, 10 patients with normal electrocardiogram (ECG) readings and no history of hypertension (healthy group), and 10 patients with hypertension and ECG criteria for left ventricular hypertrophy (LVH group). Images were obtained with Optison (Mallinckrodt Medical; IV, 1.0 mL) using harmonic imaging and low mechanical index. Posterior (PW) and septal wall (SW) thicknesses were measured at end-diastole in the parasternal long-axis view. Apical wall thickness (A) was measured from the contrast-enhanced apical endocardium to the visceral epicardial surface in the apical 4-chamber view. A/PW and A/SW ratios were calculated for each group. Asymmetric apical hypertrophy was defined as an A/PW ratio greater than 1.5. RESULTS: Contrast-enhanced apical thickness was greater than 2.0 cm in all patients in the suspected ACM group but less than 1.2 cm in all patients in the LVH and healthy groups. In all 6 patients in the suspected ACM group, A/PW and A/SW ratios were greater than 1.5. No patient in the healthy or LVH groups had thickness ratios greater than 0.85. CONCLUSION: Contrast echocardiography allows quantitative diagnosis of ACM in patients with suggestive ECG and SPECT but nondiagnostic TTEs. This study suggests that contrast echocardiography should be performed before using more expensive or invasive diagnostic testing for this condition.  相似文献   
994.
It is hypothesised that Wilms tumour (WT) results from aberrant renal development due to its embryonic morphology, associated undifferentiated precursor lesions (termed nephrogenic rests) and embryonic kidney-like chromatin and gene expression profiles. From the study of overgrowth syndrome-associated WT, germline dysregulation was identified in the imprinted region at 11p15 affecting imprinted genes IGF2 and H19. This is also detected in ~70% sporadic cases, making this the most common somatic molecular aberration in WT. This review summarises the critical discussion at an international workshop held under the auspices of The European Network for Cancer Research in Children and Adolescents (ENCCA) consortium, where the potential for drug development to target IGF2 and the WT epigenome was debated. Here, we consider current cancer treatments which include targeting the IGF pathway and the use of methylation agents alone or in combination with other drugs in clinical trials of paediatric cancers. Finally, we discuss the possibility of the use of these drugs to treat patients with WT.  相似文献   
995.
996.
This study assessed the sociodemographic, medical and psychological predictors of accuracy of perceived risk in women at increased genetic risk for ovarian cancer. Women participating in a large cohort study who were at increased risk of ovarian and fallopian tube cancer, had no personal history of cancer and had ≥1 ovary in situ at cohort enrolment, were eligible. Women completed self-administered questionnaires and attended an interview at enrolment. Of 2,868 women unaffected with cancer at cohort enrolment, 561 were eligible. 335 women (59.8 %) overestimated their ovarian cancer risk, while 215 women (38.4 %) accurately estimated their risk, and 10 (1.8 %) underestimated it. Women who did not know their mutation status were more likely to overestimate their risk (OR 1.74, 95 % CI 1.10, 2.77, p = 0.018), as were those with higher cancer-specific anxiety (OR 1.05, 95 % CI 1.02, 1.08, p < 0.001) and/or a mother who had been diagnosed with ovarian cancer (OR 1.98, 95 % CI 1.23, 3.18, p = 0.005). Amongst the group of women who did not know their mutation status, 63.3 % overestimated their risk and the mean perceived lifetime risk of developing ovarian cancer was 42.1 %, compared to a mean objective risk of 6.4 %. A large number of women at increased risk for ovarian cancer overestimate their risk. This is of concern especially in women who are at moderately increased risk only; for this sub-group of women, interventions are needed to reduce potentially unnecessary psychological distress and minimise engagement in unnecessary surgery or screening.  相似文献   
997.

Background

Dynamic postural stability is defined as the ability to transition from a dynamic movement to a stable condition over one's base of support. Measures of dynamic stability have been used extensively to classify ankle instability status and assist clinicians with ankle injury interventions. Therefore, the purpose of this study was to determine if current methods of quantifying dynamic stability are accurate in differentiating among healthy, coper, and unstable ankles.

Methods

One hundred ninety four Division-I collegiate athletes (football, volleyball, field hockey, men's/women's soccer, men's/women's lacrosse, men's/women's basketball) volunteered for this study. Participants were categorized into healthy, coper, and stable groups by a self-reported questionnaire and previous history of ankle injuries. Dynamic postural stability was assessed using the Multi-Directional Dynamic Stability Protocol by jumping and landing single-legged onto a force platform from four different directions. Receiver operator curves were used to analyze the accuracy of current techniques of calculating dynamic stability among groups.

Findings

None of the existing methods were found to be accurate in differentiating ankle instability status in any of the jump landings.

Interpretation

Researchers have commonly used these existing methods to quantify dynamic postural stability. None of the current calculation techniques worked with our jump landing protocol. Researchers need to pay attention to the protocol and calculation technique pairings in that using inaccurate measures of dynamic postural stability makes any findings of that research ineffective. Therefore, this challenges researchers to develop a more accurate calculation to quantify dynamic postural stability, or develop a jump landing protocol that exposes sensorimotor deficits in the more able-bodied population.  相似文献   
998.

Background

A common complication of hemodialysis is bleeding from the dialysis site.

Discussion

To demonstrate the use of 2-octyl-cyanoacrylate in controlling venous bleeding associated with hemodialysis access.

Conclusion

2-octyl-cyanoacrylate is effective in stopping venous bleeding from hemodialysis sites.  相似文献   
999.
1000.
We report clinical, cytogenetic, and comparative genomic hybridization findings for three siblings with an unbalanced 4q;16q translocation, minor malformations, and cognitive abnormalities, including childhood apraxia of speech, a rare, severe motor speech disorder. Breakpoint findings indicate that in addition to possible contributions from duplicated genes on chromosome 16, haploinsufficiency of one or more of 11 genes deleted in the telomeric region of the long arm of chromosome 4 is the likely cause of the speech disorder, the associated impairments in cognition and language, and the dysmorphic features. The present findings are the first to document childhood apraxia of speech in a multiplex family using contemporary speech measures. We suggest that genotype-phenotype studies of childhood apraxia of speech occurring in complex neurodevelopmental disorders can elucidate the pathophysiology of this disorder.  相似文献   
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