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921.
BACKGROUND AND AIMS: The purpose of this paper is to describe the design and diagnostic procedures of the multicenter community-based prospective Italian Project on the Epidemiology of Alzheimer's disease (I.PR.E.A.). The study is aimed at estimating the prevalence and incidence of Alzheimer's disease (AD) in the preclinical phase, examining the natural history of cognitive decline without dementia (mainly AD) in the Italian population, and identifying risk factors or health determinants related or associated with various health outcomes. METHODS: Both cross-sectional and longitudinal phases will be performed in 4800 elderly subjects aged 65-84 years. The sample will be selected from the registries of 12 Italian rural and urban municipalities, with an interval of one year between examinations. The study population will undergo several screening examinations, including personal and informant interviews by means of a structured ad hoc questionnaire, physical and neurological examination, laboratory tests, genetic markers and a neuropsychological battery. Neuroimaging screening will also be carried out in a subgroup of subjects positive for cognitive impairment without dementia. The longitudinal phase will include all subjects who, during the cross-sectional survey, are identified as affected by cognitive impairment without dementia, and will aim at assessing the incidence and natural history of cognitive impairment without dementia and the degree of disease progression from the earliest stage. This is the first systematic prospective study on the preclinical phase of AD in Italy.  相似文献   
922.
923.
SUMMARY Varicose veins cause a great deal of morbidity in our population today. Despite the large amount of surgical time spent dealing with the problem, there is still a disappointingly high recurrence rate and many patients are investigated inadequately before surgery. This review considers the assessment of ‘simple’ varicose veins using a combination of tourniquet tests and a hand-held doppler probe. The place of more sophisticated investigative techniques is also discussed, in particular the value of duplex assessment in localising the variably sited sapheno-popliteal junction. Routine stripping of the long saphenous vein to the below-knee level is likely to decrease the recurrence rate of simple, long, saphenous varicose veins.  相似文献   
924.

Objective

Despite excellent long-term results reported for a trans-aortic septal myectomy for hypertrophic obstructive cardiomyopathy (HOCM), surgery for patients with diffuse hypertrophy is very challenging. In addition, a left ventricular outflow obstruction is often aggravated by an abnormal mitral valve and subvalvular apparatus.

Methods

We performed video-assisted minimally invasive trans-mitral septal myectomy procedures in 3 patients with diffuse-type HOCM, who were highly symptomatic despite maximal medical therapy. Each had at least moderate mitral regurgitation (MR) due to systolic anterior motion (SAM). Using a right mini-thoracotomy, the anterior mitral leaflet was detached, through which an extended septal myectomy could easily be performed. Abnormal bridging chordae between the septum and papillary muscle (PM) were divided, then anterior mitral leaflet continuity was restored with direct closure or augmentation using a glutaraldehyde-treated autologous pericardium. A PM reorientation procedure was performed in 1 case in which both PMs were approximated and sutured onto the posterior ventricular wall.

Results

The postoperative course was uneventful in all patients, with marked improvement of symptoms in each. The peak ventricular outflow gradient decreased from 134?±?40 to 23?±?5 mmHg with significantly diminished SAM, especially in the patient who underwent the PM reorientation procedure. During a mean follow-up period of 42?±?14 months, no MR has been detected in any case.

Conclusions

We believe that a minimally invasive trans-mitral septal myectomy is preferable for HOCM-patients with diffuse hypertrophy and mitral valve abnormality. Aggressive PM reorientation may also be useful for those with an abnormal PM orientation.
  相似文献   
925.
杨建  田子朴 《华西医学》1992,7(3):357-359
系统观察使用异搏停停跳液的34例体外循环病例,6例(17.6%)在10~38分钟复跳。延迟复跳组和非延迟复跳组间不存在血钙等特异性因素的影响,而受年龄、心脏缺血时间和心脏张力的影响。延迟复跳心脏的功能良好,超微结构保护良好。作者对异搏停液的使用指征和延迟复跳的处理提出了建议。  相似文献   
926.
One hundred and eighteen cases of S. stercoralis infection were detected by stool examination among 4203 patients seen over a period of three years at the Division of Infectious Diseases (IRCCS, San Matteo, University of Pavia) of a University Hospital in Northern Italy. Because chronic strongyloidiasis is often asymptomatic, a 3 per cent prevalence in this selected population indicates that the parasitosis may be much more frequent in the general population of the area. Parasite-specific humoral responses were studied in 48 patients. Strongyloides-specific IgG and IgA antibodies were found by ELISA in the serum of 40 (83.3 per cent) and 43 (89.5 per cent) patients, respectively, and specific IgE antibodies were detected by RAST in 39 (81.3 per cent). The specific IgG antigen recognition patterns of these patients were compared by immunoblotting with those of North and South American and Thai patients, and differences among the groups suggested the existence of separate geographic strains of S. stercoralis. This was further supported by the virtual absence in our patients of the larva currens, a common and highly characteristic sign of strongyloidiasis in subjects infected in southeast Asia. More awareness of the epidemiologic and clinical features of strongyloidiasis, with the use of serologic tests to screen candidates for immunosuppression, may result in the early detection of chronic uncomplicated strongyloidiasis and in the prevention of fatal opportunistic hyperinfections.  相似文献   
927.
Introduction: We examined the neural mechanisms responsible for plantar flexion torque changes at different joint positions. Methods: Nine subjects performed maximal voluntary contractions (MVC) at 6 ankle–knee angle combinations [3 ankle angles (dorsiflexion, anatomic position, plantar flexion) and 2 knee angles (flexion, full extension)]. Neural mechanisms were determined by V‐wave, H‐reflex (at rest and during MVC), and electromyography during MVC (RMS), normalized to the muscle compound action potential (V/Msup, Hmax/Mmax, Hsup/Msup and RMS/Msup) and voluntary activation (VA), while muscle function was assessed by doublet amplitude. Results: MVC and doublet amplitude were significantly lower at plantar flexion (P < 0.01), while VA was significantly lower at dorsiflexion and full knee extension (P < 0.05). V/Msup and RMS/Msup were significantly lower at knee extension (P < 0.01), while Hsup/Msup was not affected by joint angle. Conclusions: These results indicate that joint positions leading to muscle lengthening produce reduced neural drive, due mainly to supraspinal mechanisms. Muscle Nerve 53 : 626–632, 2016  相似文献   
928.
黄嘌呤氧化酶对血管内皮功能障碍的影响   总被引:3,自引:0,他引:3  
目的考察黄嘌呤氧化酶(xanthine oxidase)在自发性高血压大鼠(SHR)血管舒缩及内皮功能障碍中的作用。方法采用尾套法测定SHR和正常大鼠(WKY)血压;Greiss反应测定血清一氧化氮分泌量;FRAP(ferric reduction abilitypower)法测定主动脉蛋白总抗氧化能力;RT-PCR法考察黄嘌呤氧化酶及内皮型一氧化氮合酶(eNOS)mRNA表达情况;血管环舒缩测定来评价黄嘌呤氧化酶抑制剂别嘌呤醇(oxypurinol,Oxy)对大鼠腹主动脉内皮依赖性舒张反应的影响。结果SHR血压(191.1±5.6)显著高于WKY大鼠(140.4±5.9)mmHg;SHR血清NO分泌量(28.4±5.4)、主动脉蛋白总抗氧化能力(1.02±0.14)U/μg蛋白和腹主动脉内皮依赖性舒张反应(66.2±4.6)%均显著低于WKY[分别为(51.6±5.8),(2.8±0.3)U/μgpro和81.0%±2.7%);而心、肾及主动脉中黄嘌呤氧化酶表达均显著高于WKY大鼠(P<0.05)。黄嘌呤氧化酶抑制剂Oxy能明显降低黄嘌呤氧化酶mRNA表达(降低31.6%),且改善腹主动脉内皮依赖型舒张反应(提高20.2%),但对eNOS表达则无显著影响。结论结果提示SHR中存在内皮功能障碍和氧化应激状态,黄嘌呤氧化酶参与了SHR内皮功能障碍。  相似文献   
929.
930.
Lymphocytes consist of highly heterogeneous populations, each expressing a specific cell surface receptor corresponding to a particular antigen. Lymphocytes are both the cause and regulator of various diseases, including autoimmune/allergic diseases, lifestyle diseases, neurodegenerative diseases, and cancers. Recently, immune repertoire sequencing has attracted much attention because it helps obtain global profiles of the immune receptor sequences of infiltrating T and B cells in specimens. Immune repertoire sequencing not only helps deepen our understanding of the molecular mechanisms of immune-related pathology but also assists in discovering novel therapeutic modalities for diseases, thereby shedding colorful light on otherwise tiny monotonous cells when observed under a microscope. In this review article, we introduce and detail the background and methodology of immune repertoire sequencing and summarize recent scientific achievements in association with human diseases. Future perspectives on this genetic technique in the field of histopathological research will also be discussed.  相似文献   
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