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111.
The possibility of making scientifically objective statements about health risks is part of a new complex of ideas pervading our Western social institutions. The concept of prevention includes an assessment of risk and dangers which lay persons have difficulties in comprehending. Advances in medical technology have made it possible to detect a growing number of anomalies in the human body and thereby to define more and more people as being at risk of various diseases. Even if it seems desirable for society to be able to detect the risks menacing its members, it calls for delicate management of the test procedures and of the preventive intervention. This article presents some perspectives on preventive work in connection with a directed health survey. The primary aim of the survey in question was to diagnose particular risk factors, for instance a high level of blood cholesterol, and inform the patient about how to prevent or reduce the risk of cardiovascular disease. The preventive measures are commonly undertaken by a nurse; her encounters with the patients—to obtain test samples, communicate the results and provide information about health risks—raise complex issues. These and other dilemmas in preventive work are discussed and analyzed  相似文献   
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The tutor is important for student learning in the PBL group. The students expect the tutor to monitor and steer the group process and to support the learning process, helping students to become aware of their own learning. This study aimed at investigating the PBL tutor’s role. Five PBL tutors at the Speech/Language Pathology program were interviewed regarding their view of the tutors’ role and what support they need. The analysis of the transcribed interviews focused on finding patterns and variation regarding tutor-activity at different stages in the PBL work and in their views of their progress as tutors. The results indicate that being a tutor is a balancing act and that the tutor need continuous support and input from different sources. Tutors should be encouraged to reflect on their own reactions and interventions and to be explicit and confident in their thoughts about PBL.  相似文献   
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Forty-three strains of group B streptococci (GBS) of types Ia, Ib, II and III were tested for susceptibility to chlorhexidine in concentrations ranging from 256 to 0.25 mg/l using the agar and tube dilution methods. The strains showed minimum inhibitory concentration (MIC) values ranging from 0.5 to 1 mg/l. Serum added to the test medium (50%) increased the MIC values to 4–8 mg/l, while amniotic fluid (50%) had almost no effect, increasing the values to 1–2 mg/l. The minimum bactericidal concentration (MBC) ranged from 1 to 5 mg/l. The killing kinetics were related to the concentration of chlorhexidine and the length of exposure. For example, at a concentration of 63 mg/l, 7 h were required for a bactericidal effect in broth, as compared to 1 h at 500 mg/l chlorhexidine. 200 mg/l chlorhexidine had no effect on the adherence of two GBS strains to vaginal epithelial cells, and no effect on the phagocytosis of GBS with mouse peritoneal macrophages.  相似文献   
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Endogenous Cushing's syndrome (CS) is associated with a high incidence of cardiovascular morbidity and mortality resulting from the co-existence of multiple cardiovascular risk factors which probably induce a state of endothelial dysfunction. Recently, studies conducted in vitro as well as in normal human subjects suggest a direct role of cortisol in the causation of vascular dysfunction in this disorder. We non-invasively assessed the vascular reactivity and its potential association with elevated cortisol levels in patients of CS. A single time point observational study was conducted in 18 patients of CS and 15 age and gender matched healthy subjects. Vascular reactivity was assessed non-invasively by measuring the peripheral pulse wave form changes during reactive hyperemia (RH) using digital photoplethysmography (PPG). Parameters measured were pulse wave form amplitude (PWA), slope and pulse transit time (PTT). Maximal percentage changes in PWA during RH with reference to baseline were significantly lower in the patients as compared to controls [23.19% (13.19-53.54) vs 61.71% (38.21-95.36); p=0.0079]. Normalized PTT responses during the 1(st) minute of RH were blunted in the patients as compared to controls (1.036 ± 0.026 vs 1.056 ± 0.029; p=0.0425). Percentage changes in PTT during the 2(nd) minute of RH were negatively correlated to the morning cortisol levels in patients (r = -0.6328; p=0.0064). The present study showed that endothelium mediated vascular reactivity along with myogenic regulation of vascular tone is impaired in CS. Hypercortisolism possibly plays an important role in the causation of impaired vascular reactivity and endothelial dysfunction in CS.  相似文献   
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Gram-negative bacteria have the ability to produce outer membrane-derived vesicles (OMVs) that are released into the extracellular milieu. Even though this intriguing phenomenon is well-known since many years, various aspects of bacterial OMVs are not fully described and are still in the process of being characterized in detail. One major reason for this is that depending on the bacterial species and its respective ecological niche, OMVs exhibit an enormous functional diversity. Research of the past years has clearly shown that OMVs of many pathogenic bacteria contribute to the virulence potential by enriching virulence factors and delivering them over long distances, superseding direct bacterial contact with their host. The subsequent interaction of OMVs with the host can occur at different levels regarding the type of immune response or the target cell type and may lead to different outcomes ranging from non-immunogenic activation or a pro-inflammatory response to cytotoxicity. In contrast to being virulence factors, OMVs are used for vaccination purposes in the combat against bacterial pathogens, and recent research thus is focused on to indirectly aim these versatile bacterial weapons against themselves.  相似文献   
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Insulinoma presents with myriad manifestations and severe neurological deficit may develop due to delay in diagnosis. We report a lady who presented with Glasgow coma scale of E1 M2 V1, which did not improve after correction of hypoglycemia. There was complete reversal of neurological deficit and brain magnetic resonance imaging changes of hypoglycemia on follow-up after resection of pancreatic insulinoma. This is the first report which shows reversal of hypoglycemic changes in MRI after resection of insulinoma. Insulinoma, pre and post surgery provides a model for study of the effect of hypoglycemia and its improvement after euglycemia.  相似文献   
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Hybrid anisotropic microgels were synthesised using mesoporous silica as core particles. By finely controlling the synthesis conditions, the latter can be obtained with different shapes such as platelets, primary particles or rods. Using the core particles as seeds for precipitation polymerisation, a crosslinked poly(N-isopropylacrylamide) (PNIPAM) microgel shell could be grown at the surface, conferring additional thermo-responsive properties. The different particles were characterised using scattering and imaging techniques. Small angle X-ray scattering (SAXS) was employed to identify the shape and porous organisation of the core particles and dynamic light scattering (DLS) to determine the swelling behaviour of the hybrid microgels. In addition, cryogenic transmission electron microscopy (cryo-TEM) imaging of the hybrids confirms the different morphologies as well as the presence of the microgel network and the core–shell conformation. Finally, the response of the particles to an alternating electric field is demonstrated for hybrid rod-shaped microgels in situ using confocal laser scanning microscopy (CLSM).

Hybrid anisotropic microgels with different morphologies were prepared using mesoporous silica particles as core and PNIPAM as shell. The shell thickness d and aspect ratio ρ were characterised notably via cryo-TEM (left) and DLS (right).  相似文献   
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