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101.
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   
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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   
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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   
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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   
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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   
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Hispanics have been disproportionately impacted by HIV/AIDS. Although HIV risk is significantly elevated among severely mentally ill persons (SMI), the risk of infection appears to be even greater among those SMI who are Hispanic, reflecting the increased risk of HIV among Hispanics. We report on findings from the first 41 participants in a qualitative study examining the context of HIV risk and risk reduction strategies among severely mentally ill Puerto Rican women residents in northeastern Ohio. Individuals participated in a baseline interview, two follow-up interviews, and up to 100 hours of shadowing. Interviews and shadowing activities were recorded and analyzed using a grounded theory. The majority of individuals reported using identification with a religious faith. A large proportion of the participants reported that their religious or spiritual beliefs were critical to their coping, had influenced them to reduce risk, and/or provided them with needed social support. Several participants also reported having experienced rejection from their faith communities. The emphasis on spirituality among Puerto Rican SMI is consistent with previous research demonstrating the importance of spirituality in the Hispanic culture and reliance on spiritual beliefs as a mean of coping among SMI. Our results support the incorporation of spiritual beliefs into secular HIV prevention efforts. Loue is with the Department of Epidemiology and Biostatistics, Center for Minority Public Health, School of Medicine, Case Western Reserve University, Cleveland, OH, USA; Sajatovic is with the Department of Psychiatry, School of Medicine, Case Western Reserve University, Cleveland, OH, USA.  相似文献   
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AIMS: Early invasive lobular breast carcinoma (ILC) is associated with few symptoms and signs. The individual sensitivity of clinical examination, mammography, ultrasonography, cytology and core biopsy have each been reported to be of limited value. The aim of this study was to evaluate the accuracy of triple assessment in the pre-operative detection of patients identified to have ILC from their surgical pathology. METHODS: Pure ILC was defined as tumours containing at least 90% lobular features. The triple assessment of 273 patients diagnosed primarily at our institution were reviewed. RESULTS: 87.5% of women were symptomatic and 12.5% were screen detected. The mean patient age was 59 (range 30-81) years and the median tumour size was 26 (range 5-110) mm. The main mammographic abnormalities were a spiculated lesion (33.3%), an ill-defined mass (33.3%) or architectural distortion (23.5%). The sensitivities for detecting ILC of each modality were: clinical examination (76.6%), mammography (79.8%), ultrasound examination (93.9%), fine-needle aspiration cytology (FNAC) (60.5%) and core biopsy (90.8%). Combining the three modalities of clinical examination, imaging and cyto/pathology increased the pre-operative detection rate of ILC. CONCLUSION: Triple assessment is useful in the diagnosis of ILC. As the features of ILC may be subtle, a high index of suspicion is required to facilitate early diagnosis.  相似文献   
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