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Hypertension is usually managed on a case-finding basis, and yet continued blood pressure control can be inadequate. Furthermore, hypertension is often a ‘silent’ condition until comorbid events, target organ damage and subsequent heart failure become manifest, leading to a reactive rather than a proactive approach. Management of the hypertension syndrome becomes complex, because blood pressure control may not be just an isolated concern. This review considers the various options, in addition to existing guidelines, that can help to reduce hypertension-related morbidity and mortality.  相似文献   
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运动性心律失常是指发生于机体剧烈运动期间或之后的心律失常。临床表现不一,从心悸、头晕、晕厥、心绞痛、急性心肌梗死和充血性心力衰竭,甚至到心脏性猝死。运动性心律失常可见于心肌缺血,如患有动脉粥样硬化性心脏病以及患有原发性或继发性心肌病的患者。然而,也可能发生在似乎健康的个体。在后一组人群中,运动性心律失常可以是良性的,但也可以是获得性(如药物诱发)或先天性(如先天性长QT综合征或致心律失常性右室发育不良)心电活动或结构的异常而呈恶性。这种潜在病理生理学机制的复杂性,使运动性心律失常的诊断和治疗成为临床医学上的…  相似文献   
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BACKGROUND: Beta-MHC-hRARalpha transgenic mice express a constitutively active (truncated) form of the human retinoic acid receptor which triggers development of dilated cardiomyopathy. In those hearts, we studied expression of gap junction proteins in relation to electrical impulse propagation. METHODS AND RESULTS: As compared to wildtype mice, hearts of 4-6 month old mice with 7-12 inserted hRARalpha copies are marked by an increased heart weight/body weight- and heart weight/tibia length ratio. 3-extremity lead ECGs revealed prolongation of the Q-j interval suggesting delayed ventricular activation. Mapping of electrical activity of epi- and endocardial left ventricular free wall revealed activation delay, increased heterogeneity in conduction and regional conduction block. Ventricular tachycardias did not occur spontaneously nor could be induced by ventricular pacing. Immunohistochemical analysis showed profound and heterogeneous redistribution and down-regulation of the gap junction protein connexin43 (Cx43) in the left ventricular free wall. Here, hRARalpha expression induced re-expression of the hypertrophic markers alpha-skeletal actin and beta-MHC, and in 3 out of 10 severely affected mice, re-expression of Cx40. Concomitant with changes in expression/distribution of Cx43, changes in expression and distribution of beta-catenin and N-cadherin (two other intercalated disk associated proteins) were observed. CONCLUSIONS: Beta-MHC-hRARalpha transgenic hearts show heterogeneous re-expression of (early) sarcomeric genes while expression of connexin43, N-cadherin and beta-catenin is down-regulated. We postulate that the resulting aberrant ventricular activation does not trigger development of lethal arrhythmias due to the small size of remaining healthy ventricular tissue where the transgene is not expressed.  相似文献   
35.
Aim  To investigate ventricular conduction and refractoriness before and after application of rotigaptide, an enhancer of gap junctional conductance, to explanted hearts of patients with heart failure (HF). Methods and results  In six explanted perfused hearts of patients with end-stage HF, activation/repolarization mapping was performed and refractory periods (RPs) and activation recovery intervals (ARIs) were measured before and after application of 50 nM rotigaptide. Rotigaptide caused a decrease of RP from 476 ± 36 to 453 ± 31 ms (P < 0.05), but did not change ARI-dispersion. During premature activation along the fibers rotigaptide decreased the minimal activation time (ATmin) and maximal activation time (ATmax) significantly from 35 ± 12 to 24 ± 9 and from 97 ± 38 to 43 ± 7 ms, respectively. Rotigaptide did not change ATmin and ATmax during activation perpendicular to the fiber direction. After application of rotigaptide conduction curves normalized in five/six recordings when activation was parallel, but destabilized in three/six hearts when activation was perpendicular to fiber direction. The destabilization was associated with local conduction delays rather than with facilitation of conduction. Conclusion  Rotigaptide applied to hearts of patients with end-stage HF shortened RPs normalized conduction curves and increased conduction parallel to fiber direction. However, in 50% of the hearts local slowing of conduction with destabilization of conduction (curves) occurs at sites close to the stimulation site, when activation is perpendicular to fiber direction. Returned for 1. Revision: 14 July 2008 1. Revision received: 26 August 2008 Returned for 2. Revision: 19 September 2008 2. Revision received: 31 October 2008 Returned for 3. Revision: 17 November 2008 3. Revision received: 18 November 2008  相似文献   
36.

Objectives

The aim of the study was to describe the prevalence of and examine the factors associated with immunosuppression (CD4<200 cells/μL) among HIV‐infected patients attending two large inner London treatment centres.

Methods

Patients attending for care who had a CD4 count <200 cells/μL during a 6‐month period (1 January to 30 June 2007) were identified from the UK national CD4 surveillance database. Corresponding case notes were reviewed and factors associated with the most recent immunosuppressive episode examined. Patients either previously had a CD4 count >200 cells/μL at any time under follow‐up which had decreased (group A) or never had a CD4 count >200 cells/μL (group B; late presenters).

Results

Of 4589 patients, 10.2% (467) had at least one CD4 count <200 cells/μL. In group A (60.1% of patients), 70.4% were not receiving antiretroviral therapy (ART) at the time at which the CD4 count fell to <200 cells/μL. Reasons included: treatment interruption (TI; 32.6%), patient declined ART (20.2%), infrequent attendance (19.1%), physician delay in offer (23.1%) and transient CD4 cell count decrease (3.9%). Among those receiving ART, one in three had poor adherence. In group B, 92.3% had started ART after presentation: most had recently started and were responding virologically. AIDS‐defining diagnoses occurred in the year preceding the decrease in CD4 cell count in 12.6% of patients in group A and 33.3% of those in group B.

Conclusion

The majority of patients became immunosuppressed while under care. Our findings suggest that, in addition to strategies aimed at earlier diagnosis, there are further opportunities to reduce severe immunosuppression in patients already attending for HIV care.  相似文献   
37.
ABSTRACT: BACKGROUND: A thorough understanding of the literature generated from research in care homes is required to support evidence-based commissioning and delivery of healthcare. So far this research has not been compiled or described. We set out to describe the extent of the evidence base derived from randomized controlled trials conducted in care homes. METHODS: A systematic mapping review was conducted of the randomized controlled trials (RCTs) conducted in care homes. Medline was searched for "Nursing Home", "Residential Facilities" and "Homes for the Aged"; CINAHL for "nursing homes", "residential facilities" and "skilled nursing facilities"; AMED for "Nursing homes", "Long term care", "Residential facilities" and "Randomized controlled trial"; and BNI for "Nursing Homes", "Residential Care" and "Long-term care". Articles were classified against a keywording strategy describing: year and country of publication; randomization, stratification and blinding methodology; target of intervention; intervention and control treatments; number of subjects and/or clusters; outcome measures; and results. RESULTS: 3226 abstracts were identified and 291 articles reviewed in full. Most were recent (median age 6 years) and from the United States. A wide range of targets and interventions were identified. Studies were mostly functional (44 behaviour, 20 prescribing and 20 malnutrition studies) rather than disease-based. Over a quarter focussed on mental health. CONCLUSIONS: This study is the first to collate data from all RCTs conducted in care homes and represents an important resource for those providing and commissioning healthcare for this sector. The evidence-base is rapidly developing. Several areas - influenza, falls, mobility, fractures, osteoporosis - are appropriate for systematic review. For other topics, researchers need to focus on outcome measures that can be compared and collated.  相似文献   
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Often decisions have to be made in acute situations, when there is no time for discussion. The decision may have extreme consequences for the patient. The case is reported of a girl aged 15 years with an expansively growing tumour of the uterus. An intra-abdominal haemorrhage was caused by a ruptured vascular connection. The aggressive behaviour of the tumour aroused suspicion of malignancy. At emergency laparotomy the tumour was enucleated from the uterus. Uterus and adnexa were preserved. The next problem in decision-making was the doubt concerning the pathological diagnosis: benign cellular leiomyoma or low-grade leiomyosarcoma. Now, 5 years after the laparotomy, there are no signs of recurrence. The problems concerning the diagnoses of 'leiomyoma' and 'leiomyosarcoma' are briefly reviewed.  相似文献   
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