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Twenty-three myocardial biopsies from 22 patients with various cardiological diseases were examined by light and electron microscopy. The amount of fibrosis, endocardial thickening, “whorling of myofibers”, “irregular running of myofibers”, fat infiltration and lipofuscein granules were compared to cardiological parameters such as the function group of the patients, cardiac index, stroke index and the pulmonary capillary wedge pressure. The histological grading showed a weak correlation to the function group of the patients and the pulmonary capillary wedge pressure, but not to the cardiac index or stroke index. While patients with an almost normal heart function had a normal histology, both normal and abnormal histology were seen in patiens with severe heart disease. It was not possible to relate any morphological changes in the myocardium, neither at the light microscopical nor at the ultrastructural level to specific heart diseases as for example primary or alcoholic cardiomyopathy. However, severe contraction artefacts disturbed both the light microscopical and especially the ultrastructural evaluation of the specimens.This problem is discussed and in order to diminish the risk of misinterpretation of myocardial biopsy specimens, recommendations are given with regard to fixation, mincing and embedding of the specimens as well as to the evaluation of both the light microscopic slides and the ultrathin sections.  相似文献   
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AIMS: Carotid artery stenting (CAS) for carotid artery stenoses has become an alternative to carotid endarterectomy. However, CAS itself can cause cerebral ischaemic events. Embolic protection devices (PD) promise to reduce the incidence of these events. METHODS AND RESULTS: From July 1996 to March 2003, 1483 patients from 26 hospitals were included in the prospective CAS Registry of the ALKK study group. A PD was used in 668 of 1483 patients (45%). The use of a PD has grown rapidly over the years and reached 100% in 2003. Patients treated with a PD had prior carotid artery dilatation more often (3.5% versus 1%, p < 0.001), a prior myocardial infarction (34% versus 27.4%, p = 0.007) and a history of arterial hypertension (89.9% versus 78.6%, p = 0.007) compared to patients treated without a PD. A thrombus was more often visible in patients treated under distal protection (16.5% versus 8%, p < 0.001). The use of a PD led to a 10-min longer intervention (45 min versus 35 min median, p < 0.001). Patients treated with a PD had a lower rate of ipsilateral stroke (1.7% versus 4.1%, p = 0.007) and a lower rate of all non-fatal strokes and all deaths (2.1% versus 4.9%, p = 0.004) during the hospital stay. This was confirmed by multiple logistic regression analysis (adjusted OR = 0.45, 95% CI: 0.23-0.91, p = 0.026). A similar reduction could be found for symptomatic as well as asymptomatic carotid artery stenoses. CONCLUSION: Since 1996 there has been a steady increase in the use of PDs for CAS, with a 100% use in 2003. The use of a PD may lower the rate of ipsilateral strokes during CAS.  相似文献   
14.
In this study, the effect of a simulated dive on rat brain was investigated using several magnetic resonance imaging (MRI)-methods and immunohistochemistry. Rats were randomly assigned to a dive- or a control group. The dive group was exposed to a simulated air dive to 600 kPa for 45 min. Pulmonary artery was monitored for vascular gas bubbles by ultrasound. MRI was performed 1 h after decompression and at one and 2 weeks after the dive with a different combination of MRI sequences at each time point. Two weeks after decompression, rats were sacrificed and brains were prepared for histology. Dived rats had a different time-curve for the dynamic contrast-enhanced MRI signal than controls with higher relative signal intensity, a tendency towards longer time to peak and a larger area under the curve for the whole brain on the acute MRI scan. On MRI, 1 and 2 weeks after dive, T2-maps showed no signal abnormalities or morphological changes. However, region of interest based measurements of T2 showed higher T2 in the brain stem among decompressed animals than controls after one and 2 weeks. Microscopical examination including immunohistochemistry did not reveal apparent structural or cellular injuries in any part of the rat brains. These observations indicate that severe decompression does not seem to cause any structural or cellular injury to the brain tissue of the rat, but may cause circulatory changes in the brain perfusion in the acute phase.  相似文献   
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16.

Aims

Employment status at time of first heart failure (HF) hospitalization may be an indicator of both self‐perceived and objective health status. In this study, we examined the association between employment status and the risk of all‐cause mortality and recurrent HF hospitalization in a nationwide cohort of patients with HF.

Methods and results

We identified all patients of working age (18–60 years) with a first HF hospitalization in the period 1997–2015 in Denmark, categorized according to whether or not they were part of the workforce at time of the index admission. The primary outcome was death from any cause and the secondary outcome was readmission for HF. Cumulative incidence curves, binomial regression and Cox regression models were used to assess outcomes. Of 25 571 patients with a first hospitalization for HF, 15 428 (60%) were part of the workforce at baseline. Patients in the workforce were significantly younger (53 vs. 55 years) more likely to be male (75% vs 64%) and less likely to have diabetes (13% vs 22%) and chronic obstructive pulmonary disease (5% vs 10%) (all P < 0.0001). Not being part of the workforce was associated with a significantly higher risk of death [hazard ratio (HR) 1.59; 95% confidence interval (CI) 1.50–1.68] and rehospitalization for HF (HR 1.09; 95% CI 1.05–1.14), in analyses adjusted for age, sex, co‐morbidities, education level, calendar time, and duration of first HF hospitalization.

Conclusion

Not being part of the workforce at time of first HF hospitalization was independently associated with increased mortality and recurrent HF hospitalization.
  相似文献   
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18.
Osteoarthritis (OA) and the non‐steroidal anti‐inflammatory drugs (NSAIDs) used to relieve OA‐associated pain have been linked independently to increased cardiovascular risk. We examined the risk of cardiovascular events associated with NSAID use in patients with OA. We employed linked nationwide administrative registers to examine NSAID use between 1996 and 2015 by Danish patients with OA aged ≥18 years. Using adjusted Cox proportional hazard analyses, we calculated the risk of the composite outcome of cardiovascular death, non‐fatal myocardial infarction and non‐fatal ischaemic stroke/TIA, and of each outcome separately, up to 5 years after OA diagnosis. Of 533 502 patients included, 64.3% received NSAIDs and 38 226 (7.2%) experienced a cardiovascular event during follow‐up. Compared with non‐use, all NSAIDs were associated with increased risk of the composite outcome: hazard ratio (HR) for rofecoxib, 1.90 (95% confidence interval, 1.74‐2.08); celecoxib, 1.47 (1.34‐1.62); diclofenac, 1.44 (1.36‐1.54); ibuprofen, 1.20 (1.15‐1.25); and naproxen, 1.20 (1.04‐1.39). Similar results were seen for each outcome separately. When celecoxib was used as reference, ibuprofen (HRs: 0.81 [CI: 0.74‐0.90]) and naproxen (HRs: 0.81 [0.68‐0.97]) exhibited a lower cardiovascular risk, even when low doses were compared. Low‐dose naproxen and ibuprofen were associated with the lowest risks of the composite outcome compared to no NSAID use: HRs: 1.12 (1.07‐1.19) and 1.16 (0.92‐1.42), respectively. In patients with OA, we found significant differences in cardiovascular risk among NSAIDs. Naproxen and ibuprofen appeared to be safer compared to celecoxib, also when we examined equivalent low doses. In terms of cardiovascular safety, naproxen and ibuprofen, at the lowest effective doses, may be the preferred first choices among patients with OA needing pain relief.  相似文献   
19.

Background

We recently demonstrated a survival benefit of early resection in unselected diffuse low-grade gliomas (LGG). However, heterogeneity within the LGG entity warrants investigation in a homogenous subgroup. Astrocytoma represents the largest subgroup of LGG, and is characterized by diffuse growth and inferior prognosis. We aimed to study the effects of early resection compared to biopsy and watchful waiting in this subgroup.

Methods

Patient data was retrospectively reviewed in two neurosurgical departments with regional referral practice. In one hospital, initial diagnostic biopsies and watchful waiting was favored, while early resections guided with three-dimensional (3D) ultrasound were advocated in the other hospital. This created a natural experiment with patient management heavy influenced by residential address. In the hospitals’ histopathology databases, all adult patients diagnosed with supratentorial LGG from 1998 through 2009 were screened (n?=?169) and underwent blinded histopathological review. Histopathological review concluded with 117 patients with grade II astrocytomas that were included in the present study. The primary end-point was overall survival assessed by a regional comparison.

Results

Early resections were performed in 51 (82 %) versus 12 (22 %) patients in the respective hospitals (p?<?0.001). The two patient populations were otherwise similar. Median survival was 9.7 years (95 % CI 7.5–11.9) if treated in the hospital favoring early resections compared to 5.6 years (95 % CI 3.5–7.6) if treated at the hospital favoring biopsy and watchful waiting (p?=?0.047). No difference in surgical-related neurological morbidity was seen (p?=?0.843).

Conclusions

Early 3D ultrasound guided resections improve survival, apparently without increased morbidity, compared to biopsy and watchful waiting in patients with diffuse World Health Organization (WHO) grade II astrocytomas.  相似文献   
20.
Abstract Objective. Mutations in the fibrillin-1 gene are the cause of Marfan syndrome. We wanted to investigate the relationship between a mutation in this gene and risk of prevalent hypertension. Methods. In a cross-sectional study, the effect of a G-A substitution in intron 27 in the fibrillin-1 gene (rs11856553) on risk of prevalent hypertension was studied in two large population-based studies: the Health 2006 study, consisting of 3193 women and men, age 18-69 years, and the MONICA10 study, consisting of 2408 women and men, age 41-72 years. In 1646 MONICA10 participants, blood pressure (BP) was also measured by 24-h ambulatory recordings. Results. Among the 3193 Health 2006 participants 23 had the G-A variant, and among the 2408 MONICA10 participants 18 had the G-A variant. In Health 2006, the odds ratio estimate (95% confidence intervals) for the G-A variant for risk of hypertension, defined as systolic (S) BP ≥?140 mmHg or diastolic (D) BP ≥?90 mmHg or on antihypertensive medicine, was 2.67 (1.14-6.18), p =?0.022. The corresponding figure for moderate to severe hypertension, defined as SBP ≥?160 mmHg or DBP ≥?100 mmHg, was 9.68 (4.24-22.12), p 相似文献   
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