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71.
72.

Purpose

To evaluate the ability of strain‐encoded (SENC) magnetic resonance imaging (MRI) for regional systolic and diastolic strain analysis of the myocardium in healthy volunteers.

Materials and Methods

Circumferential and longitudinal peak systolic strain values of 75 healthy volunteers (35 women and 40 men, mean age 44 ± 12 years) were measured using SENC at 1.5T. MR tagging was used as the reference standard for measuring regional function. Diastolic function was assessed in the 10 youngest (24 ± 8 years) and 10 oldest (62 ± 5 years) subjects.

Results

Peak strain values assessed with SENC were comparable to those obtained by MR tagging, showing narrow limits of agreement (limits of agreement ?5.6% to 8.1%). Regional heterogeneity was observed between different segments of the left ventricle (LV) by both techniques (P < 0.001). Longitudinal strain obtained by SENC was also heterogenous (P < 0.001). Interestingly, no age‐ or gender‐specific differences in peak systolic strain were observed, whereas the peak rate of relaxation of circumferential strain rate was decreased in the older group.

Conclusion

SENC is a reliable tool for accurate and objective quantification of regional myocardial systolic as well as diastolic function. In agreement with tagged MRI, SENC detected slightly heterogeneous myocardial strain within LV segments. J. Magn. Reson. Imaging 2009;29:99–105. © 2008 Wiley‐Liss, Inc.
  相似文献   
73.
Background  Troponin elevation in patients with stable coronary heart disease is associated with adverse outcome and prognosis. However, the mechanism is not yet clearly understood. Our objectives were to examine the prevalence and range of cardiac troponin T (cTnT) in stable patients, 6 months after acute myocardial infarction (AMI) using a new high sensitive cTnT assay and to investigate the association of minor cTnT elevation in these patients to clinical variables, NT-proBNP and cardiac MRI-findings. Study design and methods  cTnT was measured in 98 patients 6 months after AMI with a precommercial assay by electrochemiluminescence methods (Roche Diagnostics, Mannheim, Germany). cTnT values were correlated with clinical and angiographic variables, NT-proBNP concentrations and with cardiac MRI-findings. Results  Minor cTnT concentrations were detectable in 90% of the entire cohort, of whom 16% had cTnT values above the 99th percentile (>12 ng/L). These patients were also significantly older, suffered more frequently from hypertension, had a higher New York Heart Association class and received more often diuretics at follow up. Patients with cTnT elevation had a more impaired left ventricular ejection fraction (P = 0.02) but did not have an increased infarct size (P = 0.73). Conclusions  Elevated minor cTnT levels are frequently detectable in patients 6 months after AMI. Increased cTnT level were associated with clinical parameter for heart failure, impaired ejection fraction and higher NT-proBNP levels suggesting that myocardial dysfunction is a main cause for cTnT elevation in these patient group.  相似文献   
74.
Prostate cancer aggressiveness was evaluated based on pathologic characterization of cases detected in the Finnish prostate cancer screening trial. The trial population consists of 80,458 men aged 55–67 years. A total of 32,000 men were randomized to the screening arm. The remaining 48,000 men formed the control arm. The interval cases and cancers among nonparticipants and in the control arm were identified from the Finnish Cancer Registry. Random samples were selected from screen‐detected cases (126 of 543 in the first and 133 of 508 in the second round) and control arm cancers (133 out of 863), in addition to all 92 interval cancers and 106 cases among nonparticipants. All the biopsies were regraded according to the Gleason system. The expression of the proliferation antigen Ki‐67 was determined in 479 cases (72%). More than half of the tumors diagnosed in the first round of screening were high‐grade cancers (Gleason 7 or higher). In the second round, the proportion of low‐grade cancers increased from 47% to 70%. Cancers in the screening arm were more commonly focal and fewer bilateral cancers were detected. The cancers among nonparticipants were the most aggressive group. The aggressiveness of the interval cancers was between the cancers detected in the first and the second round. Our results indicate that prostate cancers detected through screening are less biologically aggressive. This was most notable after the first screening round. Nonparticipants had more aggressive cancers. © 2008 Wiley‐Liss, Inc.  相似文献   
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77.

Background

Brain tumors (BTs) in adolescence and young adulthood (AYA) differ from those in childhood or late adulthood. However, research concerning late effects in this particular survivor group is limited. This study evaluates late morbidity of survivors diagnosed in AYAs.

Methods

We identified from the Finnish Cancer Registry all survivors diagnosed with BT at the ages 16–24 years between 1970 and 2004 (N = 315) and used data from the Hospital Discharge Registry to evaluate their late (≥5 y after diagnosis) morbidity requiring treatment in a specialized health care setting. A sibling cohort of BT patients diagnosed before the age of 25 years was used as a comparison cohort (N = 3615).

Results

The AYA BT survivors had an increased risk for late-appearing endocrine diseases (HR, 2.9; 95% CI, 1.1–8.0), psychiatric disorders (HR, 2.0; 95% CI, 1.2–3.2), diseases of the nervous system (HR, 9; 95% CI, 6.6–14.0), disorders of vision/hearing loss (HR, 3.6; 95% CI, 1.5–8.5), diseases of the circulatory system (HR, 4.9; 95% CI, 2.9–8.1), and diseases of the kidney (HR, 5.9; 95% CI, 2.5–14.1). Survivors with irradiation had an increased risk for diseases of the nervous system compared with non-irradiated survivors (HR, 3.3; 95% CI, 1.8–6.2). The cumulative prevalence for most of the diagnoses remained significantly increased for survivors even 20 years after cancer diagnosis.

Conclusions

The AYA BT survivors have an increased risk of morbidity for multiple new outcomes for ≥5 years after their primary diagnosis. This emphasizes the need for structured late-effect follow-up for this patient group.  相似文献   
78.
In interleukin-10 knock out (IL-10 KO) mice, accelerated clearance of pulmonary Chlamydia pneumoniae infection was observed. On the other hand, the histopathological changes in lung tissue were more pronounced in IL-10 KO mice at all time points after infection and repeated infection than in the wild type mice. Both ex vivo induced antigen-specific proliferation as well as production of proinflammatory cytokines by splenocytes were higher in IL-10 KO mice than in WT mice. Also, intrapulmonary proinflammatory cytokine levels were higher in IL-10 KO mice than in the WT mice. The lack of anti-inflammatory action of IL-10 is likely to contribute to the enhanced clearance but severe inflammation in this experimental model.  相似文献   
79.
Distal trisomy 14q syndrome; a case report   总被引:2,自引:0,他引:2  
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80.
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