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61.
Pressure ulcer is a common occurrence in spinal cord injured (SCI) patients and can lead to serious complications. With proper management, some patients exhibit satisfactory healing whereas others show slow or nonhealing ulcers. Fibronectin has been shown to accumulate in wound, opsonize macroaggregate debris for phagocytosis, promote revascularization, and facilitate fibroblast migration and proliferation. We explored the relationship of plasma fibronectin with healing potential in 21 SCI men with pressure ulcer. They received standard wound care and were observed for eight weeks. Ten otherwise healthy SCI men without pressure ulcer (SCI-controls) and 32 able-bodied normal individuals (normal controls) were also studied. Plasma fibronectin and related proteins, ie, fibrinogen, plasminogen, alpha 2-antiplasmin and Factor XIII, were measured. Ten of 21 SCI patients with pressure ulcer showed rapid healing within four weeks and had significantly higher fibronectin levels as compared with the 11 patients with poor healing ulcers, SCI controls, and normal controls. Factor XIII and alpha 2-antiplasmin were mildly reduced and fibrinogen values were significantly increased in all SCI groups. Plasminogen concentrations were comparable in all groups studied. It thus appears that plasma fibronectin rises in patients with fast healing ulcers but fails to do so in those with poor healing ulcers and as such may be predictive of the course of pressure ulcers.  相似文献   
62.
The acute effect of dialysis on T-lymphocyte responses was studied in 11 patients with end-stage renal disease (ESRD). The in-vitro mitogenic response to concanavalin A and pokeweed mitogen was decreased (p less than 0.05) after single passage of blood through the dialyzer, accompanied by a reduction in the proportion of monoclonal antibody-defined total T lymphocytes (Leu 1+ cells) (p less than 0.01), an increase in the percentage of monoclonal antibody-defined monocytes (M 2+ cells), and a decrease in interleukin 2 (IL-2) production (p less than 0.05). Depletion of adherent cells from mononuclear cells isolated from blood after single passage through the dialyzer restored the mitogenic responses to normal levels. Post dialysis mitogenic responses were comparable to pre-dialysis mitogenic responses although IL-2 production (p less than 0.05), and the proportion of T lymphocyte (Leu 1+ cells) remained depressed (p less than 0.01). Cumulative effects of long-term intermittent hemodialysis may contribute to the impaired immunity and the increased frequency of infections and neoplasms in patients with end-stage renal disease.  相似文献   
63.
Elderly patients are increasingly being considered for kidney transplantation due to a global explosion of the aging population with end-stage renal disease (ESRD). However, mounting scarcity of available organs for transplant has led to a wider disparity between organ supply and demand. Consequently, the criteria for accepting kidneys for transplantation have been extended in an attempt to allow the use of organs from elderly donors or those with significant co-morbidities, so-called “expanded criteria donor” (ECD) kidneys. Excellent outcomes have been achieved from ECD kidneys with appropriate donor and recipient profiling and selection. With increasing recovery efforts directed at older donors, the concept of age-matching is becoming more accepted as a method of optimizing utilization of organs in elderly donors and recipients. Utilization of pulsatile perfusion has further improved ECD outcomes and helped the decision-making process for the UNOS (United Network for Organ Sharing) offer. However, age-related immune dysfunction and associated co-morbidities make the elderly transplant recipients ever more susceptible to complications associated with immunosuppressive agents. Consequently, the elderly population is at a higher risk to develop infections and malignancy in the post-transplant period notwithstanding improved transplant outcomes. Appropriate immunosuppressive agents and dosages should be selected to minimize adverse events while reducing the risk of acute rejections and maximizing patient and renal allograft survival.  相似文献   
64.
Introduction  Compression of the celiac artery by the diaphragmatic crura, the median arcuate ligament, or the fibrous periaortic ganglionic tissue results in a rare constellation of symptoms known as celiac artery compression syndrome (CACS). Anatomy  First described in 1963 by Harjola in a patient with symptoms of mesenteric ischemia, it remains an elusive diagnosis. Clinical Presentation  Patients commonly present with a wide variety of symptoms resulting in multiple diagnostic tests. Diagnosis  A firm diagnosis is difficult to establish, and treatment is equally challenging. These challenges are illustrated by the following case series, and evidence supporting current treatment modalities is reviewed. Treatment  We describe a laparoscopic approach to decompression of the celiac artery facilitated by intraoperative ultrasound.  相似文献   
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Objective

High blood pressure is one of the most important risk factors, directly responsible for increasing the cardiovascular morbidity and mortality. The primary objective was to evaluate the efficacy of metoprolol XL/chlorthalidone against metoprolol XL/hydrochlorothiazide with respect to mean fall in systolic and diastolic blood pressure. The secondary objective was to compare the response rates and to evaluate the tolerability of study medications in patients with mild-tomoderate essential hypertension.

Methods

Total 130 eligible patients (65: metoprolol XL 25 mg/chlorthalidone 6.25 mg; 65: metoprolol XL 25 mg/HCTZ 12.5 mg) were enrolled in this randomized, comparative, multicentric, 12-weeks study. Sixty-two patients from each group completed the study. After 4-weeks of treatment, non-responders from chlorthalidone 6.25 mg combination group were shifted to metoprolol XL 50 mg/chlorthalidone 12.5 mg and non-responders from HCTZ 12.5 mg combination group were escalated to metoprolol XL 50 mg/HCTZ 12.5 mg.

Results

The study treatment groups were comparable with respect to demography and baseline disease characteristics. Both the starting therapies were comparable with respect to mean fall in SBP (p = 0.788) and DBP (p = 0.939), and response rates (p = 1.0) after 4-weeks of therapy. Also both the step-up therapies showed similar mean fall in SBP (p = 0.277) and DBP (p = 0.507) at the end of 12-weeks. However, significantly more number of patients from chlorthalidone 12.5 mg/metoprolol XL 50 mg group responded to therapy as compared to that from HCTZ 12.5 mg/metoprolol XL 50 mg group (p = 0.045). All the reported adverse events were of mild-to-moderate intensity. There were no clinically significant trends in electrolytes (Na+, K+, Cl-)and fasting blood sugar, evident across the treatment groups.

Conclusion

Chlorthalidone in combination with metoprolol XL is as effective and well tolerated as widely used combination of metoprolol XL/HCTZ, thus providing an alternative therapeutic option.  相似文献   
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68.
Imaging approaches based on single molecule localization break the diffraction barrier of conventional fluorescence microscopy, allowing for bioimaging with nanometer resolution. It remains a challenge, however, to precisely localize photon-limited single molecules in 3D. We have developed a new localization-based imaging technique achieving almost isotropic subdiffraction resolution in 3D. A tilted mirror is used to generate a side view in addition to the front view of activated single emitters, allowing their 3D localization to be precisely determined for superresolution imaging. Because both front and side views are in focus, this method is able to efficiently collect emitted photons. The technique is simple to implement on a commercial fluorescence microscope, and especially suitable for biological samples with photon-limited chromophores such as endogenously expressed photoactivatable fluorescent proteins. Moreover, this method is relatively resistant to optical aberration, as it requires only centroid determination for localization analysis. Here we demonstrate the application of this method to 3D imaging of bacterial protein distribution and neuron dendritic morphology with subdiffraction resolution.  相似文献   
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Observational studies have shown a strong positive correlation between the severity of anemia and the risk of poor outcomes in patients with chronic kidney disease (CKD). This observation was initially taken to imply that adverse outcomes in CKD are caused by anemia. However, the assumption of causality ignores the possibility that anemia and adverse outcomes might be unrelated and that both are caused by underlying inflammation, oxidative stress and comorbid conditions. Randomized clinical trials of anemia correction have revealed an increased risk of adverse cardiovascular outcomes in patients assigned to normal, rather than subnormal, hemoglobin targets. As a result, correction of anemia is now considered potentially hazardous in patients with CKD. Notably, individuals who did not reach the target hemoglobin level in the clinical trials, despite receiving high doses of erythropoietin and iron, experienced a disproportionately large share of the adverse outcomes. These observations point to overdose of erythropoietin and iron, rather than anemia correction per se, as the likely culprit. This Review explores the reasons for the apparent contradiction between the findings of observational studies and randomized clinical trials of anemia treatment in CKD. I have focused on data from basic and translational studies, which are often overlooked in the design and interpretation of clinical studies and in the formulation of clinical guidelines.  相似文献   
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