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511.
Sialic acid, the acylated derivatives of 9-carbon sugar neuraminic acid, present as terminal component of oligosaccharide chains of many glycoproteins and glycolipids, has been recognized to be involved in the regulation of a great variety of biological phenomena. Studies have shown that serum sialic acid predicts both coronary heart disease and stroke mortality and reflects the existence or activity of an atherosclerotic process. Most of the studies have shown an elevation in serum sialic acid concentration in coronary heart disease and a positive correlation between the raised serum sialic acid and the severity of the coronary lesions is observed. However, a few contradictory reports are also available. Racial differences in serum sialic acid have also been reported and correlated with international differences in the prevalence of atherosclerosis. Reduced sialic acid content of platelets, erythrocytes and lipoproteins may play important role in the pathogenesis of atherosclerosis. Elucidation of the mechanism of alternation in sialic acid concentration may throw more light on its potential clinical utility. Hence more studies are needed to designates sialic acid as a cardiovascular risk factor/marker.  相似文献   
512.
Medically diagnosed alcoholics can be differentiated reliably from non-alcoholics using clinically laboratory tests. In the present study, patients with liver diseases either due to alcohol or without alcohol compared with a group of normal healthy persons. Heavy drinkers showed significantly lower body weight and percent body fat, and low BMI compared with other groups. The percentage of hemoglobin and total number of RBC were found to be significantly decreased, whereas mean corpuscular volume (MCV) significantly increased in alcoholic liver disease (ALD). Hyperbilirubinemia, hyperuricemia and hypoalbuminemia correlate with alcohol intake. Albumin/globulin ratio significantly decreased in ALD. In acute liver injury AST/ALT ratio is ≤1.0, whereas in alcoholic hepatitis it is always >1.0. Moderately elevated level of ALP and high GGT values are good discriminator of alcoholic patients. Alcohol-induced liver injury is linked to oxidative stress as observed by decreased level of reduced glutathione and ascorbic acid, and increased level of thiobarbituric acid reactive substances.  相似文献   
513.
Intraperitoneal administration of glucose (20%), Sucrose (20%) and mannitol (15%) to the rats, at a dose of 5ml/100g body weight 3 hrs. prior to hypoxic exposure (simulated high altitude 10,973m, 32°C) significantly increased the hypoxic tolerance. Intraperitoneal administration of these solutions resulted in accumulation of transudate fluid in the peritoneal cavity. A decrease in the excretion of urine, increase in hematocrit value, haemoglobin level, blood viscosity and serum protein were observed. Moisture content of lungs amongst other tissue was found to be decreased. Results are suggestive that dialysis across the peritoneal membrane might have removed some material from the blood in the peritoneal fluid which might have been responsible for the increased hypoxic tolerance.  相似文献   
514.
Serodiagnosis by ELISA has been widely explored over the years, in the diagnosis of tuberculosis. Two ELISA systems were evaluated for detection of mycobacterial antibodies in pulmonary and extra pulmonary tuberculosis. The two test assays explored were ERBA LISA (TB IgG) test (Anda Biologicals) which uses A60 antigen complex found in the cytosol of typical and atypical mycobacteria, and SEVA TB (IgG) ELISA, which uses a 31 kDa, glycoprotein antigen purified fromM. tb H37Ra culture filtrate. Sera from 98 proven tuberculosis [pulmonary TB (48), tuberculous lymphadenopathy (30), tuberculous meningitis (15) & genitourinary TB (5)] were studied along with 32 healthy controls. The overall positivity obtained using ERBA LISA (TB IgG) test and SEVA TB (IgG) ELISA test was 72.9% and 91.6% in pulmonary tuberculosis, 43.3% and 76.6% in tuberculous lymphadenopathy respectively. The sensitivity of ERBA LISA test in tuberculous meningitis and genito-urinary TB was significantly low (26.6% & 40% respectively) compared to sensitivity obtained using SEVA TB ELISA (86.6% & 60% respectively) with overall specificity of 60% and 87.5%. Thus SEVA TB IgG ELISA test was found to be more sensitive than ERBA LISA in detecting IgG antibodies in tuberculous sera, in particular in extra pulmonary tuberculosis cases.  相似文献   
515.
The adoption of e-governing practices has revolutionised the administrative machinery of governments worldwide by improving efficiency, transparency, and accountability. Researchers and administrators often aim to identify emerging research fronts and the timeline of the evolution to forecast and implement technology. In this work, we systematically investigate the trajectory of the global evolution and emerging research fronts as well as the prospects for e-governance using citation network analysis. The growth curve fitted to the number of articles published per year shows that the research activities are still in the ascendant phase. We visualise the global main path of the citation network and investigate the patterns to trace the knowledge diffusion path, major milestones, and emerging research fronts. The cluster analysis identifies the major topics of research as administration and information system management, e-governance framework design, efficiency or quality evaluation, and the application of social networks and open data leading to e-democracy. The adoption of open data and social networking for user interactions with government that leads to participatory governance are the emerging research trends. We also identify research that can have a future impact based on network parameters. The results contribute to the literature by setting the focus of future research, and assisting administrators in selecting suitable models and methodologies, and manufacturers with the development of required technical devices suitable for the upcoming phase of symbiosis.  相似文献   
516.
Anatomy is an important component in the vertical integration of basic science and clinical practice. Two common pedagogies are cadaveric dissection and examination of prosected specimens. Comparative studies mostly evaluate their immediate effectiveness. A randomized controlled trial design was employed to compare both the immediate and long-term effectiveness of dissection and prosection. Eighty third-year medical students undergoing their surgical rotation from the Yong Loo Lin School of Medicine were randomized into two groups: dissection and prosection. Each participated in a one-day hands-on course following a similar outline that demonstrated surgical anatomy in the context of its clinical relevance. A pre-course test was conducted to establish baseline knowledge. A post-course test was conducted immediately after and at a one-year interval to evaluate learner outcome and knowledge retention. A post-course survey was conducted to assess participant perception. Thirty-nine and thirty-eight participants for the dissection and prosection groups, respectively, were included for analysis. There was no significant difference between mean pre-course test scores between the dissection and prosection groups [12.6 (3.47) vs. 12.7 (3.16), P > 0.05]. Both the mean immediate [27.9 (4.30) vs. 24.9 (4.25), P < 0.05] and 1 year [23.9 (4.15) vs. 19.9 (4.05), P < 0.05] post-course test scores were significantly higher in the dissection group. However, when adjusted for course duration [dissection group took longer than prosection group (mean 411 vs. 265 min)], these findings were negated. There is no conclusive evidence of either pedagogy being superior in teaching surgical anatomy. Based on learner surveys, dissection provides a greater learner experience.  相似文献   
517.
Disparities in health and healthcare are a major concern in the United States and worldwide. Approaches to alleviate these disparities must be multifaceted and should include initiatives that touch upon the diverse areas that influence the healthcare system. Developing a strong biomedical workforce with an awareness of the issues concerning health disparities is crucial for addressing this issue. Establishing undergraduate health disparities courses that are accessible to undergraduate students in the life sciences is necessary to increase students’ understanding and awareness of these issues and motivate them to address these disparities during their careers. The majority of universities do not include courses related to health disparities in their curricula, and only a few universities manage them from their life sciences departments. The figures are especially low for minority-serving institutions, which serve students from communities disproportionally affected by health disparities. Universities should consider several possible approaches to infuse their undergraduate curricula with health disparities courses or activities. Eliminating health disparities will require efforts from diverse stakeholders. Undergraduate institutions can play an important role in developing an aware biomedical workforce and helping to close the gap in health outcomes.  相似文献   
518.
519.
Given the frequent critiques of elite universities for admitting low numbers of state school graduates and, more recently, British Afro‐Caribbean students, how do students attending those universities make meaning of the admissions process? Through an analysis of 46 one‐on‐one in‐depth interviews with undergraduates attending Oxford University, we show that students believe in the fairness of the admissions process, while lamenting the lack of opportunities for educational advancement faced by some disadvantaged youth in British society. Despite their understanding that many British youth do not have access to educational experiences that make Oxbridge an attainable goal, most students do not support changes to make access more equitable across class or racial/ethnic lines. This perspective, which legitimates the status students gain through matriculation at an elite university, supports the maintenance of unequal access to an Oxford education despite the advantages that education is known to confer to graduates. The findings demonstrate elites acknowledging the disadvantages of particular groups in society without acknowledging their own advantages in the same system. They do so by recognizing two elements of merit: (1) intelligence, which most students assumed led to their own admission; and (2) cultivation of that intelligence, which requires elite secondary schools and which most students see as disadvantaging particular groups in society. In the paper we highlight differences in meaning‐making between graduates of grammar, comprehensive and private schools.  相似文献   
520.

Background and objective

It has been shown that macrophages play an important role in the development of severe acute pancreatitis (SAP), and eventually lead to multiple organ failure (MOF). Clodronate-liposome selectively depleted macrophages. This study was to investigate the role of renal macrophage infiltration in acute renal injury in rats with SAP and to evaluate the potential of superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging (MRI) for diagnosis.

Methods

Superparamagnetic Fe3O4 nanoparticles were prepared by chemical coprecipitation. SPIO-liposomes and SPIO-clodronate-liposomes were prepared by the thin film method. SAP models were prepared by injection of sodium taurocholate into the subcapsular space of rat pancreas. Sprague-Dawley rats were randomly divided into a control group, SAP plus SPIO-liposome (P) group, and SAP plus SPIO-clodronate-containing liposome (T) group. Kidney injury was evaluated by T2-weighted MRI scan. The levels of serum amylase (SAM), blood urea nitrogen (BUN), and serum creatinine (SCr) were measured by an automated enzymatic method. Serum tumor necrosis factor-α (TNF-α) was measured by enzyme-linked immunosorbent assay (ELISA). Pathological changes in the pancreas and kidney were observed using hematoxylin and eosin (H&E) staining, while cell apoptosis was detected with terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. In addition, the macrophage markers (CD68) of the renal tissue were detected with immunohistochemistry.

Results

The pathological changes in the pancreas and kidneys of rats in the T group were milder than those in the P group. The MRI signal intensity of the kidneys in the P and T groups was significantly lower than that in the control group. There were significant changes in the two experimental groups (P<0.01). The levels of SAM, Bun, SCr, and TNF-α in rats in the P group were higher than those in the control group (P<0.01) and in the T group (P<0.01). The apoptosis of the kidney in the T group was higher than that in the P group at 2 and 6 h (P<0.01).

Conclusions

Clodronate-containing liposomes protected against renal injury in SAP rats, and SPIO can be used as a tracer for MRI examination to detect renal injury in SAP rats. SPIO-aided MRI provided an efficient non-invasive way to monitor the migration of macrophages after renal injury in rats with SAP.  相似文献   
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