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In South Africa, 7-valent pneumococcal conjugate vaccine (PCV) was introduced in April 2009 and replaced with 13-valent PCV in April 2011. We describe the epidemiology of serotype 1 Streptococcus pneumoniae disease during the pre- and post-PCV eras (2003–2013). Using laboratory-based invasive pneumococcal disease (IPD) surveillance, we calculated annual incidences, identified IPD clusters, and determined serotype 1–associated factors. Of 46,483 IPD cases, 4,544 (10%) were caused by serotype 1. Two clusters of serotype 1 infection were detected during 2003–2004 and 2008–2012, but incidence decreased after 2011. Among children <5 years of age, those who had non–serotype 1 IPD had shorter hospital stays, fewer cases of penicillin-nonsusceptible disease, and lower HIV prevalence and in-hospital death rates than did those with serotype 1 IPD; similar factors were noted for older patients. Serotype 1 IPD had distinctive clinical features in South Africa, and annual incidences fluctuated, with decreases noted after the introduction of PCV13.  相似文献   
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Background

Although laparoscopic fundoplication effectively alleviates gastroesophageal reflux disease (GERD) in the great majority of patients, some patients remain dissatisfied after the operation. This study was undertaken to report the outcomes of these patients and to determine the causes of dissatisfaction after laparoscopic fundoplication.

Methods

All patients undergoing laparoscopic fundoplication in the authors’ series from 1992 to 2010 were evaluated for frequency and severity of symptoms before and after laparoscopic fundoplication, and their experiences were graded from “very satisfying” to “very unsatisfying.” Objective outcomes were determined by endoscopy, barium swallow, and pH monitoring. Primary complaints were derived from postoperative surveys. Median data are reported.

Results

Of the 1,063 patients undergoing laparoscopic fundoplication, 101 patients reported dissatisfaction after the procedure. The follow-up period was 33 months. The dissatisfied patients (n = 101) were more likely than the satisfied patients to have postoperative complications (9 vs 4 %; p < 0.05) and to have undergone a prior fundoplication (22 vs 11 %; p < 0.05). For the dissatisfied patients, heartburn decreased in frequency and severity after fundoplication (p < 0.05) but remained notable. Also for the dissatisfied patients, new symptoms (gas bloat/dysphagia) were the most prominent postoperative complaint (59 %), followed by symptom recurrence (23 %), symptom persistence (4 %), and the overall experience (14 %). Primary complaints of new symptoms were most common within the first year of follow-up assessment and less frequent thereafter. Primary complaints of recurrent symptoms generally occurred more than 1 year after fundoplication.

Conclusions

Dissatisfaction is uncommon after laparoscopic fundoplication. New symptoms, such as dysphagia and gas/bloating, are primary causes of dissatisfaction despite general reflux alleviation among these patients. New symptoms occur sooner after fundoplication than recurrent symptoms and may become less common with time.  相似文献   
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Object naming is commonly used for demonstrating semantic memory abilities, known to be affected in normal aging. Yet, neuropsychological assessments of older people do not reflect irregularities. The authors used a test with 2 levels of naming complexity by 2 kinds of stimuli: common objects pictured from a conventional viewpoint (usual condition) or from an unconventional viewpoint (unusual condition). The authors studied naming performance with 129 healthy participants, aged 20-85 years. For the usual stimuli, the success rate was high (90.9%), with no reduction in performance until 65 years of age. However, for the unusual stimuli, there was a marked reduction in performance with age. Brain activity was studied on 11 healthy young participants (20-30 years of age) using functional magnetic resonance imaging. The usual condition activated brain regions associated with visual perception, language, and memory. Additional brain regions associated with semantic searching and decision making were obtained in the unusual condition in the prefrontal cortex (Brodmann's area [BA] 9 and BA 47) and anterior cingulate (BA 32). The results suggest that the poor naming performance for unusual-viewed objects in older people might be related to the shrinkage of frontal gray matter with age.  相似文献   
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Artificial intelligence holds great promise for improved health‐care outcomes. But it also poses substantial new hazards, including algorithmic discrimination. For example, an algorithm used to identify candidates for beneficial “high risk care management” programs routinely failed to select racial minorities. Furthermore, some algorithms deliberately adjust for race in ways that divert resources away from minority patients. To illustrate, algorithms have underestimated African Americans’ risks of kidney stones and death from heart failure. Algorithmic discrimination can violate Title VI of the Civil Rights Act and Section 1557 of the Affordable Care Act when it unjustifiably disadvantages underserved populations. This article urges that both legal and technical tools be deployed to promote AI fairness. Plaintiffs should be able to assert disparate impact claims in health‐care litigation, and Congress should enact an Algorithmic Accountability Act. In addition, fairness should be a key element in designing, implementing, validating, and employing AI.  相似文献   
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Physician burnout is receiving more attention in the medical literature, and deservedly so. For example, in October of 2019, the National Academies of Sciences, Engineering, and Medicine published a lengthy report called Taking Action against Clinician Burnout: A Systems Approach to Professional Well‐Being. The report is comprehensive and well worth reading, and it offers a series of sound recommendations for addressing the burnout problem. However, the recommendations are quite ambitious, and implementing them would require a considerable investment of time, staffing, and financial resources. The medical community should not be left to grapple with the phenomenon of physician burnout alone. The law has a significant role to play in addressing the problem. As a first step, it is useful to consider a few concrete interventions that regulators could realistically implement in the short term.  相似文献   
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To develop a localized drug delivery system that offers prolonged administration of metronidazole into the periodontal pocket, muccoadhesive gel formulations containing 5% w/w metronidazole were prepared using the bioadhesive polymers: carboxymethylcellulose, methylcellulose, hydroxyethylcellulose, polyvinylpirrolidone, and carbopol. Increased concentrations of the polymers decreased the drug release rate and enhanced syringeability, yield value, and adhesiveness but decreased the spreadability. The bioadhesive properties of the gels were affected by pH and Ca 2+ concentration. The gel containing 20% hydroxyethylcellulose, 20% polyvinylpirrolidone, and 1% carbopol exhibited zero-order drug release kinetics and suitable physical properties for drug delivery to the periodontal pocket.  相似文献   
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Human fetal development depends on the ability of the embryo to gain access to the maternal circulation. Thus, specialized stem cells of the newly formed placenta, trophoblast, invade the uterus and its arterial network to establish an efficient feto-maternal molecular exchange. To accomplish this task, trophoblast differentiation during the first trimester of pregnancy involves cell proliferation, invasion, and extracellular matrix (ECM) remodelling. Trophoblast invasion shares many features with tumour cell invasion, with the distinction that it is strictly spatially and temporally controlled. We have previously demonstrated that PAR1, the first member of the protease-activated receptor (PAR) family, plays a central role in tumour cell invasion. In the present study we have examined the pattern of expression of PAR1 and other PAR family candidates during early human placental development. We show that PAR1 and PAR3 are highly and spatially expressed between the 7th and 10th weeks of gestation but not at the 12th week and thereafter. Likewise, high expression levels of PAR1 and PAR3 were observed in the cytotrophoblast cells of complete hydatidiform mole as compared to minimal levels in normal age-matched placenta. Together, our data suggest the involvement of PAR1 and PAR3 in restricted and unrestricted pathological trophoblast invasion.  相似文献   
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