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41.
Characteristics of intestinal metaplasia in the gastric cardia   总被引:8,自引:0,他引:8  
OBJECTIVE: Intestinal metaplasia of the gastroesophageal junction is frequently grouped together with Barrett's esophagus. The area of the gastroesophageal junction is comprised of the distal esophagus and the gastric cardia. The aim of the present study was to assess whether intestinal metaplasia in the distal esophagus and gastric cardia represent two different entities with a different set of risk factors. METHODS: Patients presenting for elective upper endoscopy were enrolled into a prospective study. The presence of gastritis and intestinal metaplasia was evaluated in gastric biopsies taken from the antrum, corpus, and cardia. Barrett's esophagus was defined by the presence of any length of columnar mucosa above the gastroesophageal junction. RESULTS: Of 302 patients, 50 patients had intestinal metaplasia of the gastric cardia, 73 Barrett's esophagus, and 116 erosive esophagitis. Men were more prone than women to develop Barrett's esophagus or erosive esophagitis. Both conditions were also more common among whites than nonwhites. Smoking was particularly common among patients with Barrett's esophagus. Patients with cardiac intestinal metaplasia did not share these demographic characteristics. The prevalence of daily reflux symptoms, erosive esophagitis, and Barrett's esophagus was similar among patients both with and without cardiac intestinal metaplasia. However, atrophy and intestinal metaplasia of the gastric antrum and corpus were found more frequently among patients with than without cardiac intestinal metaplasia. CONCLUSIONS: Intestinal metaplasia of the gastric cardia is different from Barrett's esophagus. Although cardiac intestinal metaplasia is closely associated with signs of gastritis in other parts of the stomach, gastroesophageal reflux disease does not seem to be a risk factor. A diagnosis of Barrett's esophagus should not be made based on the presence of intestinal metaplasia within the cardiac portion of the gastroesophageal junction.  相似文献   
42.
Continuous subcutaneous insulin infusion (CSII) using pumps is a widely used method for insulin therapy in patients with diabetes mellitus. Among the major factors that usually lead to the discontinuation of CSII are CSII set-related issues, including infection at the infusion site. The American Diabetic Association currently recommends rotating sites every 2 to 3 days. This recommendation adds cost and creates inconvenience. Therefore, in order to prevent infections and extend the duration between insertion site changes, we developed a Teflon cannula coated with a combination of gentian violet and chlorhexidine (gendine) and tested its antimicrobial efficacy against different pathogens. The cannulas were coated with gendine on the exterior surface and dried. The efficacy and durability of gendine-coated cannulas were determined against methicillin-resistant Staphylococcus aureus, Staphylococcus epidermidis, methicillin-susceptible S. aureus, Streptococcus pyogenes, vancomycin-resistant enterococci, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, and Candida glabrata using a biofilm colonization method. The cytotoxicity of gendine was assessed against mouse fibroblast cell lines. The gendine-coated cannulas showed complete prevention of biofilm colonization of all organisms tested for up to 2 weeks (P < 0.0001) compared to that with the uncoated control. A gendine-coated catheter against mouse fibroblast cells was shown to be noncytotoxic. Our in vitro results show that a novel gendine cannula is highly effective in completely inhibiting the biofilm of multidrug-resistant pathogens for up to 2 weeks and may have potential clinical applications, such as prolonged use, cost reduction, and lower infection rate.  相似文献   
43.
Clostridium tetani, the etiologic agent of tetanus, produces a toxin that causes spastic paralysis in humans and other vertebrates. This study was aimed for isolation, identification, and determination of antimicrobial susceptibility of C. tetani from clinically diagnosed tetanus patients. Isolation was done from deep-punctured tissues of the foot and arm injuries of 80 clinically diagnosed tetanus patients from the Pakistan Institute of Medical Sciences hospital. We successfully screened out five C. tetani isolates out of 80 samples based on the strain-specific characteristics confirmed through biochemical testing and toxin production. A disc diffusion method was used for antimicrobial susceptibilities and C. tetani isolates showed susceptibility to cefoperazone, chloramphenicol, metronidazole, penicillin G, and tetracycline, but were found to be resistant to erythromycin and ofloxacin. During animal testing, all the infected mice developed symptoms of tetanus. The results showed that identification of C. tetani is possible using biochemical and molecular tools and that the strains of C. tetani isolated had not developed resistance against the antibiotics most often used for the treatment of tetanus.  相似文献   
44.
45.
Background Percutaneous coronary interventions (PCIs) in patients with multivessel coronary artery disease (CAD) may be staged or performed in a single session. No data exist about the relative safety and efficacy of these 2 strategies. Our aim was to compare short-term and long-term outcomes of patients with multivessel CAD who underwent PCI in 1 versus 2 sessions. Methods and Results The study included 264 consecutive patients who underwent treatment in our center during 1997 and 1998. PCI was conducted in a single session in 129 patients and was staged in 135 patients. The mean interval between the sessions in the staged group was 45.6 ± 22.3 days. The rates of major adverse cardiac events (MACEs) during in-hospital stay did not differ significantly between the staged (combined for both stages) and nonstaged groups (2.2% vs 4.6%; P = .28). A trend for lower event rates at 30-day (2.9% vs 6.9%; P = .13) and 1-year follow-up (26.1 vs 35.9; P = .08) favored the staged arm. Diameter stenosis ≥50% was found in 17% of patients in the staged group in the second session and was successfully retreated in most of them. No MACE occurred between the sessions. Multivariate analysis identified staging of the procedure as a single independent predictor of MACE at 1-year follow-up (P = .05). Conclusion Our results suggest that a practical staging strategy within 4 to 8 weeks is safe and allows for identification and treatment of potential excessive proliferative response in the previously intervened lesions during the second procedure. (Am Heart J 2002;143:1017-26.)  相似文献   
46.

Background

Work engagement is a positive, fulfilling affective and motivational state of work-related wellbeing and a protective factor for workers' mental health. The aim of the present study was to examine the association between psychological distress (conceptualised as the target variable), job satisfaction, and work engagement in contexts of low-intensity warfare and political violence. According to the salutogenic perspective, the relationship between job satisfaction and psychological distress is influenced by the level of work engagement.

Methods

We selected a convenience sample of 380 Palestinian teachers from Gaza (40%, 152 out of 380) and the West Bank (60%, 228 out of 380). The participants were recruited on-site during morning breaks from the classroom teaching activity. The selection criteria were being in a teaching position, and working in a primary or lower secondary school. The participants completed the Arabic versions of the Teacher Job satisfaction Scale (TJSS-9), the General Health Questionnaire (GHQ-12) and the Utrecht Work Engagement Scale (UWE-SF). The statistical strategy was based on structural equation modelling. The study was approved by the Ethical Board of the University of Milano Bicocca. Informed written consent was obtained from all participants.

Findings

The General Health Questionnaire cumulative score revealed a medium to high level of psychological distress (mean 18·68 [SD 4·03]) among teachers, but high job satisfaction (mean 27·18 [SD 5·65]). The structural model showed an excellent fit (χ2 (23)=69·6, p<0·0001, NC=3·021, NFI=0·939, NNFI=0·959, CFI=0·958, RMSEA=0·073). Job satisfaction and psychological distress had a moderate and inverse relationship that was, statistically speaking, fully mediated by the level of work engagement (F=17·05, p<0·001, R2=0·16). The direct effect of job satisfaction on work engagement was positive and medium (according to Cohen, 1988) in strength.

Interpretation

The main finding of the study is that work engagement may mediate the impact of job satisfaction on teachers' psychological distress by lessening the effect of difficult working conditions. It further suggests that in order to mediate the effect of low job satisfaction on psychological distress of teachers, organisational policies and practices should focus on improving employees' work engagement. This means that, in developing job programmes for teachers in contexts characterised by difficult working conditions, the main focus must be to increase the level of subjective resources (eg, inner states, emotional activation, personal motivational processes) and workers' engagement rather than focusing primarily on job satisfaction.

Funding

None.  相似文献   
47.
Objectives:To explore the changing patterns of long-stay patients (LSP) to improve the utilization of pediatric intensive care units (PICUs) resources.Methods:This is a 2-points cross-sectional study (5 years apart; 2014-2019) conducted among PICUs and SCICUs in Riyadh, Saudi Arabia. Children who have stayed in PICU for more than 21 days were included.Results:Out of the 11 units approached, 10 (90%) agreed to participate. The prevalence of LSP in all these hospitals decreased from 32% (48/150) in 2014 to 23.4% (35/149) in 2019. The length of stay ranged from 22 days to 13.5 years. The majority of LSP had a neuromuscular or cardiac disease and were admitted with respiratory compromise. Ventilator-associated pneumonia was the most prevalent complication (37.5%). The most commonly used resources were mechanical ventilation (93.8%), antibiotics (60.4%), and blood-products transfusions (35.4%). The most common reason for the extended stay was medical reasons (51.1%), followed by a lack of family resources (26.5%) or lack of referral to long-term care facilities (22.4%).Conclusion:A long-stay is associated with significant critical care bed occupancy, complications, and utilization of resources that could be otherwise utilized as surge capacity for critical care services. Decreasing occupancy in this multicenter study deserves further engagement of the healthcare leaders and families to maximize the utilization of resources.  相似文献   
48.
In this paper, poly(3,4-ethylenedioxythiophene)/graphitic carbon nitride (PEDOT/g-C3N4) composites were prepared by the bromine catalysed polymerization (BCP) method with varying weight ratios of monomer to g-C3N4. For comparison, solid-state polymerization (SSP) and metal oxidative polymerization (MOP) methods were also used for the synthesis of PEDOT/g-C3N4 composites. Electrochemical determination of heavy metal ions (Cd2+ and Pb2+) was carried out by differential pulse voltammetry (DPV) on composite-modified glass carbon electrodes (GCEs), which were prepared by different methods. The obtained composites were analysed by Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible absorption spectroscopy (UV-vis), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results showed that the bromine catalysed polymerization (BCP) method is an effective way to prepare the PEDOT/g-C3N4 composite, and the combination of PEDOT with g-C3N4 can improve the electrochemical activity of electrode materials. And, the composite from the BCP method modified electrode (PEDOT/10 wt% g-C3N4/GCE) exhibited the widest linear responses for Cd2+ and Pb2+, ranging from 0.06–12 μM and 0.04–11.6 μM with detection limits (S/N = 3) of 0.0014 μM and 0.00421 μM, respectively.

The PEDOT/g-C3N4 composite prepared by a Br2-catalyzed polymerization method exhibited the widest linear electrochemical responses for Cd2+ and Pb2+.  相似文献   
49.
Fibroblast growth factor‐19 (FGF‐19) is a gut hormone which interacts with metabolism and is depleted in obesity. There is some indication that the hormone undergoes a resurgence following bariatric surgery (BS), an effect which may contribute to the beneficial outcomes of such procedures. This systematic review and meta‐analysis aims to synthesize the available literature on FGF‐19 levels before and after BS. MEDLINE, Scopus and Web of Science databases were searched, and the effect of different surgical procedures and degrees of body mass index (BMI) reduction on FGF‐19 levels was assessed by DerSimonian and Laird random‐effects model in meta‐analysis and dose–response analyses. This meta‐analysis, which included 474 patients from 25 arms undergoing one of five BS procedures, revealed a significant increase in the levels of circulating FGF‐19 following all‐type BS. Vertical sleeve gastrectomy, duodenal‐jejunal bypass liner and Roux‐en‐Y gastric bypass all significantly increased circulating FGF‐19 levels from baseline. However, gastric banding failed to achieve the same, and in fact, biliopancreatic diversion was associated with decreased circulating FGF‐19. Finally, an inverse association between FGF‐19 and the degree of BMI‐reduction post‐operatively was noted. FGF‐19 is increased by BS and may represent a pharmaceutical target in efforts to reproduce the beneficial effects of BS in a medical setting.  相似文献   
50.

Background

Human papillomaviruses (HPV) are oncogenic and mainly associated with cervical cancers. Recent evidence has demonstrated HPV infection in other tissues, including oral epithelia and mucosa. Although a recent pilot study provided new information about oral HPV status in healthy adults from Nevada, no information was obtained about oral HPV prevalence among children or teenagers, therefore, the goal of this study is to provide more detailed information about oral prevalence of high-risk HPV among children and teenagers in Nevada.

Methods

This retrospective study utilized previously collected saliva samples, obtained from pediatric dental clinic patients (aged 2 – 11) and local school district teenagers (aged 12-17) for high-risk HPV screening (n=118) using qPCR for quantification and confirmation of analytical sensitivity and specificity.

Results

A small subset of saliva samples were found to harbor high-risk HPV16 (n=2) and HPV18 (n=1), representing a 2.5% of the total. All three were obtained from teenage males, and two of these three samples were from White participants.

Conclusions

Although this retrospective study could not provide correlations with behavioral or socioeconomic data, this project successfully screened more than one hundred saliva samples for high-risk HPV, confirming both HPV16 and HPV18 strains were present in a small subset. With increasing evidence of oral HPV infection in children, this study provides critical information of significant value to other dental, medical, oral and public health professionals who seek to further an understanding of oral health and disease risk in pediatric populations.
  相似文献   
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