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161.
CONTEXT: Depressive symptoms are common in patients with dementia and may be associated with increased risk of developing dementia. It has been hypothesized that depressive symptoms and dementia may be attributable to underlying vascular disease in some older persons. OBJECTIVES: To test the hypotheses (1) that depressive symptoms are associated with increased risk of developing mild cognitive impairment (MCI), a preclinical state that often precedes dementia, and (2) that the association between depressive symptoms and MCI is attributable to underlying vascular disease. DESIGN: Prospective, population-based, longitudinal study. SETTING: Random sample of adults 65 years or older recruited from 4 US communities. PARTICIPANTS: Subjects were 2220 participants in the Cardiovascular Health Study Cognition Study with high cognitive function at baseline. Depressive symptoms were measured at baseline using the 10-item Center for Epidemiological Studies Depression Scale and were classified as none (0-2 points), low (3-7 points), and moderate or high (>/=8 points). Vascular disease measures at baseline included confirmed history of stroke, transient ischemic attack, diabetes mellitus, or hypertension; carotid artery stenosis; ankle-arm blood pressure index; and small or large infarcts or white matter disease on cerebral magnetic resonance imaging. Mild cognitive impairment was diagnosed after 6 years of follow-up based on the consensus of a team of dementia experts using standard clinical criteria. MAIN OUTCOME MEASURE: Diagnosis of MCI. RESULTS: Depressive symptoms at baseline were associated with increased risk of MCI (10.0%, 13.3%, and 19.7% for those with no, low, and moderate or high depressive symptoms, respectively). This association was diminished only slightly by adjustment for vascular disease measures and demographics. Vascular disease measures also were associated with increased risk of MCI, and these associations were not diminished by adjustment for depressive symptoms or demographics. CONCLUSION: Depressive symptoms were associated with increased risk of MCI, and this association was independent of underlying vascular disease.  相似文献   
162.

Objective

Surgical technique in total knee arthroplasty (TKA) to combine the femur first and tibia first techniques in order to reduce surgical mistakes regarding rotation and alignment.

Indications

Symptomatic arthritis of the knee.

Contraindications

General contraindications for TKA.

Surgical technique

Osseous preparation starting with a distal femur cut. Then the proximal tibia cut is accomplished and the knee is balanced in extension after checking for correct alignment. Bone-referenced positioning of the femoral cutting block for further preparation of the femur. Finally, the rotation of the femur is checked in 90° of flexion by means of ligament tension. If required, the rotation is checked and the flexion gap balanced, respectively.

Postoperative management

Mobilization with weight bearing and range of motion as tolerated.

Results

In a prospective study, 267?knees (160 women, 107 men, average age of 69.3 [46?C89]?years) were followed up preoperatively and after 6 weeks. The clinical results were based on the American Knee Society score. The scores were 48.9 (32?C68) preoperatively and 86.5?(75?C100) at follow-up. Radiologically 92.1% of the knees showed a malposition <3°.  相似文献   
163.
Aortopulmonary window is a rare defect caused by failure of fusion of the two opposing conotruncal ridges that are responsible for separating the truncus arteriosus into the aorta and pulmonary artery. Aortopulmonary window may occur as an isolated lesion or it can be associated with other cardiac abnormalities in one third to one half of cases. The most common associated lesions are arch abnormalities, specifically interrupted aortic arch and coarctation of the aorta. Antenatal diagnosis is rare. In the current era, early mortality following repair of simple aortopulmonary window approaches zero and depends on the presence of associated lesions, especially interrupted aortic arch. Long-term outcome should be excellent. Early morbidity includes pulmonary artery stenosis and residual aortopulmonary septal defects. Long-term follow-up is indicated to look for recurrent lesions such as the development of branch pulmonary artery stenosis and arch obstruction.  相似文献   
164.

Background

With the demands faced by anesthetists and intensive care physicians apparently increasing continuously in Germany, the increased risk of burnout in comparison with the general working population is discussed. This debate has previously been merely speculative because of the lack of studies comparing the burn-out risk of the German working population with anesthetists. Accordingly it was not certain whether anesthetists really are at greater risk of developing burnout as has often been suggested. Moreover, age, gender, function, workplace environment, e.g. working at a hospital compared to a general practitioner (GP) surgery, may influence the risk of burnout. Therefore, this study examined whether the risk for anesthetists in Germany suffering from burnout really is greater than in other occupations. In addition, factors influencing the burnout risks of anesthetists were analyzed.

Method

A total of 3,541 questionnaires completed by German aaesthetists for a study on work satisfaction by the CBI (Copenhagen Burnout Inventory, part of the Copenhagen Psychosocial Questionnaire, COPSOQ) were analyzed. Apart from calculating the number of participants with a high risk of developing burnout syndrome, the data were used to calculate a generalized burnout score for all participants. The score was compared with data from both a random sample representing a wide variety of occupations from among the general population in Germany (n?=?4,709) and a random sample of German hospital doctors (n?=?616). In addition, subgroups were formed by gender, function (senior consultant, senior physician, specialist, junior doctor) and type and place of work (university hospital, public hospital, private clinic, GP surgery, freelance work) and the proportion of each group with a high risk of burnout syndrome was calculated. In addition, general burnout scores were compared statistically for differences among the various groups.

Results

The proportion of study participants with a high risk of burnout was 40.1%. Differences were found to exist between genders (male 37.2% versus female 46%), qualifications (senior consultant 28.9%, senior physician 38%, specialist 41.5%, junior doctor 46.7%) and working in a hospital (41.3%) compared to a GP surgery (33.2%). The random sample of hospital doctors (n?=?616) showed a burnout score of 49?±?19 (mean?±?standard deviation), compared to 44?±?19 for a random sample of the German population (n?=?4,709) and 42?±?19 for anesthetists (p??0.05). Working in a hospital was found to result in higher burnout scores than in a GP surgery or freelance work (43?±?19.2 versus 38.1?±?20.5; t(3531)?=?5.0, p?Conclusions Despite 40.1% of anesthetists being at high risk of burnout, generally speaking the risk of burnout among anesthetists was not higher than in other occupational groups in Germany. However, burnout risks for specific groups, such as female junior doctors in anesthesia, were higher and the possibility of providing social support in the workplace should be considered.  相似文献   
165.
MR line scan diffusion imaging of the brain in children   总被引:3,自引:0,他引:3  
BACKGROUND AND PURPOSE: MR imaging of the self-diffusion of water has become increasingly popular for the early detection of cerebral infarction in adults. The purpose of this study was to evaluate MR line scan diffusion imaging (LSDI) of the brain in children. METHODS: LSDI was performed in four volunteers and 12 patients by using an effective TR/TE of 2736/89.4 and a maximum b value of 450 to 600 s/mm2 applied in the x, y, and z directions. In the volunteers, single-shot echo planar imaging of diffusion (EPID) was also performed. The patients (10 boys and two girls) ranged in age from 2 days to 16 years (average age, 6.6 years). Diagnoses included acute cerebral infarction, seizure disorder, posttraumatic confusion syndrome, complicated migraine, residual astrocytoma, encephalitis, hypoxia without cerebral infarction, cerebral contusion, and conversion disorder. In all patients, routine spin-echo images were also acquired. Trace images and apparent diffusion coefficient maps were produced for each location scanned with LSDI. RESULTS: In the volunteers, LSDI showed less chemical-shift and magnetic-susceptibility artifact and less geometric distortion than did EPID. LSDI was of diagnostic quality in all studies. Diffusion abnormalities were present in five patients. Restricted diffusion was present in the lesions of the three patients with acute cerebral infarction. Mildly increased diffusion was present in the lesions of encephalitis and residual cerebellar astrocytoma. No diffusion abnormalities were seen in the remaining seven children. CONCLUSION: LSDI is feasible in children, provides high-quality diffusion images with less chemical-shift and magnetic-susceptibility artifact and less geometric distortion than does EPID, and complements the routine MR examination.  相似文献   
166.
Retroperitoneoskopische Nierenchirurgie   总被引:1,自引:0,他引:1  
Retroperitoneoscopy enables quick, simple, and direct access to the retroperitoneal cavity. We describe our operative technique and discuss the advantages and disadvantages of retroperitoneoscopy. We report on our experience with this operative technique after 360 procedures: nephrectomy, partial nephrectomy, living donor nephrectomy, cryotherapy of renal tumors, pyeloplasty, adrenalectomy, and further operations. In addition, we discuss indications that are suitable for beginners to retroperitoneoscopy and some topics that require special attention.  相似文献   
167.
A large variety of approaches are described for standard total hip arthroplasty. All of them are technically based on three different approaches: anterior, anterolateral, or posterior. In recent hip resurfacing, the posterior approach is common, due to large instruments used to ream the femur. Better exposure of the acetabulum is achieved by the posterior approach, but this technique puts the important extraosseous blood supply to the femoral head at risk. The anterior approach preserves blood supply and gives better options to treat the femoroacetabular impingement. If specific surgical modifications and instruments designed for minimally invasive surgery are used, hip resurfacing can be performed with an anterolateral technique. Excellent functional and clinical outcomes have been reported after all three approaches.  相似文献   
168.
For more than 20 years percutaneous vertebroplasty has been used in the minimally invasive treatment of vertebral fractures. We report on a patient with embolisation of bone cement into the pulmonary artery and the right ventricle, which was perforated. The final diagnosis was delayed due to a combination of complications, previous disorders as well as a second embolisation.  相似文献   
169.
PURPOSE: Post-carotid endarterectomy, thrombosis, and intimal hyperplasia may be decreased by the inhibition of platelet adhesion and activation. In this study, a novel agent, saratin, was used to inhibit platelet-to-collagen adhesion in a rat carotid endarterectomy model. Saratin is a recombinant protein isolated from the saliva of the medicinal leech Hirudo medicinalis, which is thought to act by binding to collagen, and inhibits von Willebrand factor-collagen interaction under conditions of increased shear and therefore, the adherence and activation of platelets at the vessel wall. Saratin has the advantage of being a nonsystemic, site-specific topical application. METHODS: A rat carotid endarterectomy model was used in which an open technique with arteriotomy and intimectomy was used. Saratin was applied to the endarterectomized surface of the carotid artery before arterial closure. End point measurements included platelet adhesion, thrombosis rate, intimal hyperplasia development, bleeding times, and platelet counts. Electron micrographs of carotid arteries were used for quantitative analysis of platelet aggregation and platelet counts. Intimal hyperplasia and thrombosis were assessed with computer-assisted morphometric analysis of elastin-stained carotid artery sections with direct measurement of the intimal hyperplasia area. RESULTS: The topical application of saratin significantly decreased platelet adhesion compared with controls at 3 hours after carotid endarterectomy (64 +/- 17 vs 155 +/- 33 platelets per grid, P = .05), and 24 hours after carotid endarterectomy (35 +/- 11 vs 149 +/- 37 platelets per grid, P = .0110), respectively. A percent luminal stenosis, as a measure of intimal hyperplasia, was significantly decreased with saratin application compared with controls (10.9% +/- 1.8% vs 29.8% +/- 6.8%, P = .0042). This decrease in intimal hyperplasia formation correlated with the inhibition of platelet adhesion. Thirty-three percent of control arteries were found to be thrombosed 2 weeks after carotid endarterectomy compared with a 0% thrombosis rate in the saratin-treated group (P = .0156). No increased bleeding was encountered along the arterial suture line in the saratin group. Bleeding times and systemic platelet counts were not found to change significantly in the saratin-treated rats compared with control rats at 3 and 24 hours after endarterectomy. CONCLUSION: Saratin significantly decreased platelet adhesion, intimal hyperplasia, luminal stenosis, and thrombosis after carotid endarterectomy in rats. Saratin did not increase suture line bleeding or bleeding times, and did not decrease platelet counts. Saratin may serve as a topical agent to be used for the site-specific inhibition of thrombosis and intimal hyperplasia after vascular manipulation.  相似文献   
170.
Hyperinsulinism of infancy (HI) is a congenital defect in the regulated release of insulin from pancreatic beta-cells. Here we describe stimulus-secretion coupling mechanisms in beta-cells and intact islets of Langerhans isolated from three patients with a novel SUR1 gene defect. 2154+3 A to G SUR1 (GenBank accession number L78207) is the first report of familial HI among nonconsanguineous Caucasians identified in the U.K. Using patch-clamp methodologies, we have shown that this mutation is associated with both a decrease in the number of operational ATP-sensitive K+ channels (KATP channels) in beta-cells and impaired ADP-dependent regulation. There were no apparent defects in the regulation of Ca2+- and voltage-gated K+ channels or delayed rectifier K+ channels. Intact HI beta-cells were spontaneously electrically active and generating Ca2+ action currents that were largely insensitive to diazoxide and somatostatin. As a consequence, when intact HI islets were challenged with glucose and tolbutamide, there was no rise in intracellular free calcium ion concentration ([Ca2+]i) over basal values. Capacitance measurements used to monitor exocytosis in control and HI beta-cells revealed that there were no defects in Ca2+-dependent exocytotic events. Finally, insulin release studies documented that whereas tolbutamide failed to cause insulin secretion as a consequence of impaired [Ca2+]i signaling, glucose readily promoted insulin release. Glucose was also found to augment the actions of protein kinase C- and protein kinase A-dependent agonists in the absence of extracellular Ca2+. These findings document the relationship between SUR1 gene defects and insulin secretion in vivo and in vitro and describe for the first time KATP channel-independent pathways of regulated insulin secretion in diseased human beta-cells.  相似文献   
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