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101.
Michelle G Jansen Ludovica Griffanti Clare E Mackay Melis Anatürk Luca Melazzini Ann-Marie G de Lange Nicola Filippini Enik Zsoldos Kim Wiegertjes Frank-Erik de Leeuw Archana Singh-Manoux Mika Kivimki Klaus P Ebmeier Sana Suri 《Journal of cerebral blood flow and metabolism》2022,42(4):600
We characterize the associations of total cerebral small vessel disease (SVD) burden with brain structure, trajectories of vascular risk factors, and cognitive functions in mid-to-late life. Participants were 623 community-dwelling adults from the Whitehall II Imaging Sub-study with multi-modal MRI (mean age 69.96, SD = 5.18, 79% men). We used linear mixed-effects models to investigate associations of SVD burden with up to 25-year retrospective trajectories of vascular risk and cognitive performance. General linear modelling was used to investigate concurrent associations with grey matter (GM) density and white matter (WM) microstructure, and whether these associations were modified by cognitive status (Montreal Cognitive Asessment [MoCA] scores of < 26 vs. ≥ 26). Severe SVD burden in older age was associated with higher mean arterial pressure throughout midlife (β = 3.36, 95% CI [0.42-6.30]), and faster cognitive decline in letter fluency (β = −0.07, 95% CI [−0.13–−0.01]), and verbal reasoning (β = −0.05, 95% CI [−0.11–−0.001]). Moreover, SVD burden was related to lower GM volumes in 9.7% of total GM, and widespread WM microstructural decline (FWE-corrected p < 0.05). The latter association was most pronounced in individuals who demonstrated cognitive impairments on MoCA (MoCA < 26; F3,608 = 2.14, p = 0.007). These findings highlight the importance of managing midlife vascular health to preserve brain structure and cognitive function in old age. 相似文献
102.
Wireless Body Area Network (WBAN) consists of low-power, miniaturized, and autonomous wireless sensor nodes that enable physicians
to remotely monitor vital signs of patients and provide real-time feedback with medical diagnosis and consultations. It is
the most reliable and cheaper way to take care of patients suffering from chronic diseases such as asthma, diabetes and cardiovascular
diseases. Some of the most important attributes of WBAN is low-power consumption and delay. This can be achieved by introducing
flexible duty cycling techniques on the energy constraint sensor nodes. Stated otherwise, low duty cycle nodes should not
receive frequent synchronization and control packets if they have no data to send/receive. In this paper, we introduce a Traffic-adaptive
MAC protocol (TaMAC) by taking into account the traffic information of the sensor nodes. The protocol dynamically adjusts
the duty cycle of the sensor nodes according to their traffic-patterns, thus solving the idle listening and overhearing problems.
The traffic-patterns of all sensor nodes are organized and maintained by the coordinator. The TaMAC protocol is supported
by a wakeup radio that is used to accommodate emergency and on-demand events in a reliable manner. The wakeup radio uses a
separate control channel along with the data channel and therefore it has considerably low power consumption requirements.
Analytical expressions are derived to analyze and compare the performance of the TaMAC protocol with the well-known beacon-enabled
IEEE 802.15.4 MAC, WiseMAC, and SMAC protocols. The analytical derivations are further validated by simulation results. It
is shown that the TaMAC protocol outperforms all other protocols in terms of power consumption and delay. 相似文献
103.
This research examined the prevalence of step turns and spin turns during turning while walking in healthy older adults. The potential effect of magnitude of the turn and walking velocity on the prevalence of the step and spin turns were also investigated by examining the participants’ performance as they made 45° and 90° turns while walking at three different velocities. Results showed that healthy older adults in our study preferred spin turns while walking either slower or faster than their natural walking speed. Only during 90° turns while walking fast the participants showed a preference for step turns over spin turns. Spin turns are less stable and have a greater biomechanical cost than step turns. The high incidence of spin turns in older adults may contribute to the higher risk of falling in this population. 相似文献
104.
105.
A Primary Health Care Programme was initiated in a squatter settlement of Karachi with the aim of increasing the awareness regarding the importance of hygiene, immunization, oral rehydration (ORS), nutrition, and so on. A minimum of four resource personnel were able to reach 700 individuals by means of a 'snow-balling' effect. Primary Health Care Workers from the area were required to provide health education to mothers in the Community. A post-intervention survey revealed health education (intervention) was successful in modifying the approach of home-management of diarrhoea, fever and respiratory tract infections. Literacy also influenced home-management of diarrhoea and fever. Thus, health education not only changed the awareness and knowledge of the Community, but also successfully altered health practices which is reflected in reduced incidence of these diseases. 相似文献
106.
With the widespread use of recombinant erythropoietin (EPO) for patients with end-stage renal disease (ESRD), management of iron deficiency is an ongoing issue for the renal team. Effective iron replacement and maintenance play a vital role in efficient use of EPO. For hemodialysis patients, intravenous (i.v.) iron has proven convenient and, as an ancillary drug outside of the composite rate, generates profits for dialysis facilities. Improvements in the vehicle with which i.v. iron is administered have led to a reduction in severe or fatal reactions common with iron dextran products. Oral iron has had a spotty track record as an effective therapy for dialysis patients. Compliance has been hindered by patient discomfort when taking oral iron. Patients on peritoneal dialysis and those with chronic kidney disease remain good candidates for oral iron because of convenience, and oral formulas could prove more effective even in the hemodialysis patient population if they were better tolerated and better absorbed, and if using them would not place an economic burden on the patient and/or an economic hardship on the facility. In a capitated/bundled payment environment, oral iron may become a blessing rather than a curse for facilities that need to find more economic ways of providing services. Heme-iron, now undergoing clinical studies, may be a reliable replacement for i.v. iron in that scenario. 相似文献
107.
INTRODUCTION: The purpose of this study was to optimize carbon tetrachloride-induced hepatotoxicity in the rat with respect to dose, route of injection, and time course. METHODS: Male Wistar albino rats, 4 to 6 weeks old and weighing 130-180 g were used. Hepatotoxicity was evaluated by measuring the activity of serum enzymes (alkaline phosphatase [ALP], alanine aminotransferase [ALT], and aspartate aminotransferase [AST]) as well as serum total bilirubin level. RESULTS: Intraperitoneal injection of carbon tetrachloride (CCl(4)) increased the activity of ALP (from 64.9 to 137.3 U/l), ALT (from 106.6 to 693.1 U/l), and AST (from 113.8 to 693.9 U/l). Plasma bilirubin level increased (from 0.119 to 0.42 mg/dl). In contrast, subcutaneous injection of CCl(4) had no effect on these variables. The optimum intraperitoneal dose of CCl(4) was found to be 2 ml/kg body weight (dissolved in an equal volume of olive oil), and this increased the level of bilirubin and the activity of the three enzymes significantly, without causing death of the animals. Hepatotoxicity was observed within 2 h of intraperitoneal injection of CCl(4) and reached a peak after 24 h. Bilirubin level and serum enzyme activities declined gradually to normal levels by 3 days after CCl(4) injection. CONCLUSION: It is possible to reliably evoke reversible hepatotoxicity in rats by intraperitoneal injection of 2 ml/kg CCl(4). 相似文献
108.
Gheith OA Sobh MA Mohamed Kel-S El-Baz MA El-Husseini F Gazarin SS Ahmed HA Rasem MW Amer GM 《Nephron》2002,91(4):612-619
In this study 43 patients with idiopathic nephrotic syndrome were randomly distributed into 2 age- and sex-matched groups. The first group was given fluvastatin while the second was used as control. The cases in the 2 groups were evaluated clinically, biochemically (creatinine clearance, albumin, 24-hour proteinuria, and lipogram), neurologically, and histopathologically (examination of renal biopsies obtained basally and after 1 year of treatment with fluvastatin). In the fluvastatin-treated group but not in the control group, we observed a significant reduction in cholesterol, low-density lipoprotein, and triglyceride. Clinical and laboratory assessment showed satisfactory tolerance of the drug by the patients. Proteinuria, serum albumin and creatinine clearance values were significantly better in the statin-treated patients. There was no difference in glomerular sclerosis between the 2 groups while interstitial fibrosis and renal fat deposits were less in the statin-treated group. The reduction in renal fat deposits in the statin-treated group was highly significant, while that of interstitial fibrosis was not. We conclude that: (1) statin can be safely and effectively used in the treatment of dyslipidemia in patients with persistent idiopathic nephrotic syndrome; (2) control of dyslipidemia in nephrotic patients is associated with better control of proteinuria and creatinine clearance; (3) statin treatment may cause regression of renal fat deposits in patients with nephrotic syndrome, and (4) longer term studies are still required to study further possible beneficial effects on renal histology and disease progression. 相似文献
109.
The anterior hernia or the fissure of Larrey and Bochdalek hernia are exceptional in adult. We present 6 cases of congenital diaphragmatic hernia revealed in adult. Three hernia of the fissure of Larrey and three Bochdalek hernia. We discuss the different clinical, radiological, and therapeutic aspects of these hernia. We insist on the gravity of strangulated hernia and their surgical treatment. 相似文献
110.
Reisberg B Franssen EH Souren LE Auer SR Akram I Kenowsky S 《American journal of Alzheimer's disease and other dementias》2002,17(4):202-212
Retrogenesis is the process by which degenerative mechanisms reverse the order of acquisition in normal development. Alzheimer's disease (AD) and related conditions in the senium have long been noted to resemble "a return to childhood" Previously, we noted that the functional stages of AD precisely and remarkably recapitulated the acquisition of the same functional landmarks in normal human development. Subsequent work indicated that this developmental recapitulation also applied to the cognitive and related symptoms in AD. Remarkably, further investigations revealed that the same neurologic "infantile" reflexes, which mark the emergence from infancy in normal development, are equally robust indicators of corresponding stages in AD. Neuropathologic and biomolecular mechanisms for these retrogenic processes are now evident. For example, the pattern of myelin loss in AD appears to mirror the pattern of myelin acquisition in normal development. Also, recent findings indicate that mitogenic factors become reactivated in AD, and, consequently, the most actively "growing" brain regions are the most vulnerable. Because of this robust retrogenic process, the stages of AD can be translated into corresponding developmental ages (DAs). These DAs can account for the overall management and care needs of AD patients. A science of AD management can be formulated on the basis of the DA of the Alzheimer's patient, taking into consideration differences of AD from normal development as well as homologies. 相似文献