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101.
In an attempt to address a shortage of clinical nursing placements, the rising complexity of care and to increase preparedness of students entering clinical settings, the provincial government of Ontario invested significant funding for the purchase of simulation equipment in undergraduate Schools of Nursing. What students believe about simulation and learning can influence how it is used and can also provide faculty with a better understanding of how it can best be implemented. This study explored nursing students’ viewpoints about the use of simulation in their nursing programs. Q-methodology was the research approach used. In total, 24 students from 17 universities and colleges participated in the study. Although all students felt that simulated experiences could support learning overall, four groups of students were identified who had differing viewpoints. Described as reflectors, reality skeptics, comfort seekers, and technology savvies, these four groups of students require unique approaches to better engage them in learning with simulation. This study provides recommendations for faculty to consider, taking into account these varied viewpoints regarding simulation in nursing education.  相似文献   
102.
Acute invasive pulmonary aspergillosis is a rapidly progressive and frequently lethal infection. Relatively little is known about early events in the pathogenesis and relationship between the cell wall biomarkers galactomannan and (1→3)-β-d-glucan. The consequences of delayed antifungal therapy are also poorly defined. A persistently neutropenic rabbit model of invasive pulmonary aspergillosis was used to describe the histopathology of early invasive pulmonary aspergillosis and the kinetics of galactomannan and (1→3)-β-d-glucan. The time course of both molecules was mathematically modeled by using a population methodology, and Monte Carlo simulations were performed. The effect of progressive delay in the administration of amphotericin B deoxycholate 1 mg/kg at 24, 48, 72, and 96 h postinoculation on fungal burden, lung weight, pulmonary infarct score, and survival was determined. Histopathology showed phagocytosis of conidia by pulmonary alveolar macrophages at 4 h postinoculation. At 12 to 24 h, there was a progressive focal inflammatory response with conidial germination and hyphal extension. Subsequently, hyphae invaded into the contiguous lung. Galactomannan and (1→3)-β-d-glucan had similar trajectories, and both exhibited considerable interindividual variability, which was reflected in Monte Carlo simulations. Concentrations of both molecules began to rise <24 h postinoculation before pulmonary hemorrhagic infarction was present. Delays of 72 and 96 h in the administration of amphotericin B resulted in fungal burdens and lung weights that were indistinguishable from those of controls, respectively. Galactomannan and (1→3)-β-d-glucan have similar kinetics and are comparable biomarkers of early invasive pulmonary aspergillosis. Antifungal treatment at ≥48 h postinoculation is associated with suboptimal therapeutic outcomes.Acute invasive pulmonary aspergillosis is a leading cause of morbidity and mortality in immunocompromised patients. There have been considerable efforts to improve the diagnostic accuracy and therapeutic outcomes associated with this frequently lethal infection. A better understanding of the relationship of clinically relevant biomarkers and the pathogenesis of invasive pulmonary aspergillosis would facilitate further development of strategies to identify and treat patients at the earliest possible time.Galactomannan and (1→3)-β-d-glucan are complex carbohydrate cell wall molecules produced by Aspergillus spp. The diagnostic and prognostic value of these biomarkers in experimental models and humans is relatively well characterized (7, 12, 17, 18, 23). Despite this, there is little understanding of the relationship of the time course of galactomannan and (1→3)-β-d-glucan to early events in the pathogenesis of invasive pulmonary aspergillosis, and no studies that have rigorously compared their kinetics in laboratory animals or humans.Recently, we described the kinetics of galactomannan in persistently neutropenic rabbits with early invasive pulmonary aspergillosis (12). In the present study, we extend our previous findings by defining the critical histopathological events in early invasive pulmonary aspergillosis and further characterize and compare the kinetics of the circulating fungal antigens galactomannan and (1→3)-β-d-glucan. We further explore the consequences of delayed antifungal therapy with amphotericin B deoxycholate to provide insight into the period after inoculation in which favorable therapeutic outcomes can be secured in profoundly immunocompromised hosts.  相似文献   
103.
PurposeAccelerated partial breast irradiation (APBI) offers several advantages over whole breast irradiation. Electronic brachytherapy may further reduce barriers to breast conserving therapy by making APBI more available. However, its toxicity profile is not well characterized.Methods and MaterialsA 60-year-old woman was treated with APBI using Axxent (Xoft, Sunnyvale, CA) electronic brachytherapy. One month after APBI, a cycle of docetaxel and cyclophosphamide was given. Within 3 weeks, the patient developed an ulcerative radiation recall reaction in the skin overlying the lumpectomy cavity. To investigate this toxicity, the skin dose from electronic brachytherapy was compared with the dose that would have been delivered by an iridium-192 (192Ir) source. Additionally, a dose equivalent was estimated by adjusting for the increased relative biologic effectiveness (RBE) of low energy photons generated by the electronic source.ResultsUsing electronic brachytherapy, the skin dose was 537 cGy per fraction compared with 470 cGy for an 192Ir source. Given an RBE for a 40 kV source of 1.28 compared with 192Ir, the equivalent dose at the skin for an electronic source was 687 cGy-equivalents, a 46% increase.ConclusionsWe present a case of an ulcerative radiation recall reaction in a patient receiving APBI with electronic brachytherapy followed by chemotherapy. Our analysis shows that the use of electronic brachytherapy resulted in the deposition of significantly higher equivalent dose at the skin compared with 192Ir. These findings suggest that standard guidelines (e.g., surface-to-skin distance) that apply to 192Ir-based balloon brachytherapy may not be applicable to electronic brachytherapy.  相似文献   
104.
105.
The better understanding of the clinically important behavioral features of new instrument systems has an important significance for the clinical endodontics. This study aimed to investigate the shaping and centering ability as well as cyclic fatigue resistance of HyFlex CM (CM), HyFlex EDM (EDM) and EdgeFile (EF) thermally treated nickel–titanium (NiTi) endodontic instrument systems. Sixty curved root canals of the mesial roots of mandibular molars were randomly assigned into three groups (n = 20) and shaped using CM, EDM and EF files up to the size 40 and taper 04 of the instruments. µCT scanning of the specimens before and after preparation was performed and the morphometric 2D and 3D parameters were evaluated in the apical, middle and coronal thirds of root canals. In each group, 40.04 instruments (n = 20) were subjected to the cyclic fatigue resistance test in artificial root canals at 37 °C temperature until fractures occurred, and the number of cycles to failure (NCF) was calculated. The fractographic analysis was performed using a scanning electron microscope, evaluating topographic features and surface profiles of the separated instruments. The one-way analysis of variance with post hoc Tuckey’s test was used for statistical analysis of the data; the significance level was set at 5%. All systems prepared the comparable percentage of root canal surface with the similar magnitude of canal transportation in all root thirds (p > 0.05), but demonstrated significantly different resistance to cyclic fatigue (p < 0.05). The most resistant to fracture was EF, followed by EDM and CM. The length of the fractured fragments was not significantly different between the groups, and fractographic analysis by SEM detected the typical topographic features of separated thermally treated NiTi instrument surfaces.  相似文献   
106.
Lasers in Medical Science - The present work is devoted to the development of a new system for collecting and drying patient exhalation samples for a laser photo-acoustic gas analyzer for express...  相似文献   
107.
Objective Identifying influenza A or B as cause of influenza-like illness (ILI) is a challenge due to non-specific symptoms. An accurate, cheap and easy to use biomarker might enhance targeting influenza-specific management in primary care. The aim of this study was to investigate if C-reactive protein (CRP) is associated with influenza A or B, confirmed with PCR testing, in patients presenting with ILI.Design Cross-sectional study.Setting Primary care in Lithuania, Norway and Sweden.Subjects A total of 277 patients at least 1 year of age consulting primary care with ILI during seasonal influenza epidemics.Main outcome measures Capillary blood CRP analysed as a point-of-care test and detection of influenza A or B on nasopharyngeal swabs in adults, and nasal and pharyngeal swabs in children using PCR.Results The prevalence of positive tests for influenza A among patients was 44% (121/277) and the prevalence of influenza B was 21% (58/277). Patients with influenza A infection could not be identified based on CRP concentration. However, increasing CRP concentration in steps of 10 mg/L was associated with a significantly lower risk for influenza B with an adjusted odds ratio of 0.42 (0.25–0.70; p<.001). Signs of more severe symptoms like shortness of breath, sweats or chills and dizziness were associated with higher CRP.Conclusions There was no association between CRP and influenza A. Increased concentration of CRP was associated with a lower risk for having influenza B, a finding that lacks clinical usefulness. Hence, CRP testing should be avoided in ILI, unless bacterial pneumonia is suspected.

Key points

  • Identifying influenza A or B as cause of influenza-like illness (ILI) is a challenge due to non-specific symptoms. There was no association between concentration of CRP and influenza A.
  • Increased concentration of CRP was associated with a lower risk for having influenza B, a finding that lacks clinical usefulness.
  • A consequence is that CRP testing should be avoided in ILI, unless bacterial pneumonia or similar is suspected.
  相似文献   
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110.
Micafungin (FK463) is an echinocandin that demonstrates potent in vitro antifungal activities against Candida and Aspergillus species. However, little is known about its comparative antifungal activities in persistently neutropenic hosts. We therefore investigated the plasma micafungin pharmacokinetics and antifungal activities of micafungin against experimental disseminated candidiasis and invasive pulmonary aspergillosis in persistently neutropenic rabbits. The groups with disseminated candidiasis studied consisted of untreated controls (UCs); rabbits treated with desoxycholate amphotericin B (DAMB) at 1 mg/kg of body weight/day; or rabbits treated with micafungin at 0.25, 0.5, 1, and 2 mg/kg/day intravenously. Compared with the UCs, rabbits treated with micafungin or DAMB showed significant dosage-dependent clearance of Candida albicans from the liver, spleen, kidney, brain, eye, lung, and vena cava. These in vivo findings correlated with the results of in vitro time-kill assays that demonstrated that micafungin has concentration-dependent fungicidal activity. The groups with invasive pulmonary aspergillosis studied consisted of UCs; rabbits treated with DAMB; rabbits treated with liposomal amphotericin B (LAMB) at 5 mg/kg/day; and rabbits treated with micafungin at 0.5, 1, and 2 mg/kg/day. In comparison to the significant micafungin dosage-dependent reduction of the residual burden (in log CFU per gram) of C. albicans in tissue, micafungin-treated rabbits with invasive pulmonary aspergillosis had no reduction in the concentration of Aspergillus fumigatus in tissue. DAMB and LAMB significantly reduced the burdens of C. albicans and A. fumigatus in tissues (P < 0.01). Persistent galactomannan antigenemia in micafungin-treated rabbits correlated with the presence of an elevated burden of A. fumigatus in pulmonary tissue. By comparison, DAMB- and LAMB-treated animals had significantly reduced circulating galactomannan antigen levels. Despite a lack of clearance of A. fumigatus from the lungs, there was a significant improvement in the rate of survival (P < 0.001) and a reduction in the level of pulmonary infarction (P < 0.05) in micafungin-treated rabbits. In summary, micafungin demonstrated concentration-dependent and dosage-dependent clearance of C. albicans from persistently neutropenic rabbits with disseminated candidiasis but not of A. fumigatus from persistently neutropenic rabbits with invasive pulmonary aspergillosis.  相似文献   
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