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101.

Background:

Maps show well the spatial configuration of information. Considerable effort is devoted to the development of geographical information systems (GIS) that increase understanding of public health problems and in particular to collaborate efforts among clinicians, epidemiologists, ecologists, and geographers to map and forecast disease risk.

Objectives:

Small populations tend to give rise to the most extreme disease rates, even if the actual rates are similar across the areas. Such situations will follow the decision-maker''s attention on these areas when they scrutinize the map for decision making or resource allocation. As an alternative, maps can be prepared using P-values (probabilistic values).

Materials and Methods:

The statistical significance of rates rather than the rates themselves are used to map the results. The incidence rates calculated for each village from 2000 to 2009 is used to estimate λ, the expected number of cases in the study area. The obtained results are mapped using Arc GIS 10.0.

Results:

The likelihood of infections from low to high is depicted in the map and it is observed that five villages namely, Odanthurai, Coimbatore Corporation, Ikkaraiboluvampatti, Puliakulam, and Pollachi Corporation are more likely to have significantly high incidences.

Conclusion:

In the probability map, some of the areas with exceptionally high or low rates disappear. These are typically small unpopulated areas, whose rates are unstable due to the small numbers problem. The probability map shows more specific regions of relative risks and expected outcomes.  相似文献   
102.

Background

Cholecystitis is an inflammation of the gallbladder that most commonly occurs as a result of obstruction of the cystic duct by gallstones. The current standard of treatment for acute cholecystitis is cholecystectomy.

Objective

Our goal was to discuss the benefits of and compare early laparoscopic cholecystectomy and delayed laparoscopic cholecystectomy in the treatment of acute cholecystitis.

Materials and Methods

A Medline literature search was performed dating from January 1982 to July 2015. We limited the search to human studies written in English and using the keywords “Acute Cholecystitis,” early vs. delayed laparoscopic cholecystectomy, surgical management, and surgical complications.

Results

There were 225 articles reviewed, of which 25 met criteria for selection. Our recommendations are based on these 25 articles.

Conclusion

Early laparoscopic cholecystectomy is preferred over delayed, due to overall better quality of life, lower morbidity rates, and lower hospital cost. Ultimately, management of acute cholecystitis by emergency physicians should be made based on patient's clinical status and available resources in their particular hospital.  相似文献   
103.

Purpose:

Ocular trauma is a major cause of acquired monocular blindness in children. Firework injuries account for 20% of ocular trauma. The purpose of our study was to document the profile of ocular firework injuries in children during the festive season of Diwali and to determine the prevalence of unilateral blindness in them.

Materials and Methods:

A retrospective chart analysis of ocular firework injury in children during the festival of Diwali from 2009 to 2013, conducted in a tertiary care eye center in Tamil Nadu, Southern India. Children below 18 years of age with ocular firework injuries who presented to the emergency department for 3 consecutive days - the day of Diwali, 1 day before, and 1 day after Diwali - were included in this study.

Results:

Eighty-four children presented with firework-related ocular injuries during the study period. Male to female ratio was 4:1 with mean age 9.48 ± 4 years. Forty-four percentage required hospitalization. The prevalence of unilateral blindness in children due to fireworks was found to be 8% (95% confidence interval - 2–13%).

Conclusion:

Vision 2020 gives high priority to avoidable blindness, especially in children. In our study, for every 12 children who presented with firecracker injury, one resulted in unilateral blindness. This is an avoidable cause of blindness. Awareness needs to be created, and changes in policy regarding sales and handling of firecrackers including mandatory use of protective eyewear should be considered.  相似文献   
104.
Recent developments in the study of the structure and function of opioid receptors raise significant challenges for the definition of individual receptor types and the development of a nomenclature that precisely describes isoforms that may subserve different functions in vivo. Presentations at the 2013 meeting of the International Narcotics Research Conference in Cairns, Australia, considered some of the new discoveries that are now unravelling the complexities of opioid receptor signalling. Variable processing of opioid receptor messenger RNAs may lead to the presence of several isoforms of the μ receptor. Each opioid receptor type can function either as a monomer or as part of a homo- or heterodimer or higher multimer. Additionally, recent evidence points to the existence of agonist bias in the signal transduction pathways activated through μ receptors, and to the presence of regulatory allosteric sites on the receptors. This brief review summarizes the recent discoveries that raise challenges for receptor definition and the characterization of signal transduction pathways activated by specific receptor forms.

LINKED ARTICLES

This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2  相似文献   
105.
Several studies suggest that heteromerization between μ (MOP) and δ (DOP) opioid receptors modulates the signalling properties of the individual receptors. For example, whereas activation of MOP receptors by an agonist induces G protein-mediated signalling, the same agonist induces β-arrestin-mediated signalling in the context of the MOP-DOP receptor heteromer. Moreover, heteromer-mediated signalling is allosterically modulated by a combination of MOP and DOP receptor ligands. This has implications in analgesia given that morphine-induced antinociception can be potentiated by DOP receptor ligands. Recently reagents selectively targeting the MOP-DOP receptor heteromer such as bivalent ligands, antibodies or membrane permeable peptides have been generated; these reagents are enabling studies to elucidate the contribution of endogenously expressed heteromers to analgesia as well as to the development of side-effects associated with chronic opioid use. Recent advances in drug screening technology have led to the identification of a MOP-DOP receptor heteromer-biased agonist that activates both G protein-mediated and β-arrestin-mediated signalling. Moreover, this heteromer-biased agonist exhibits potent antinociceptive activity but with reduced side-effects, suggesting that ligands targeting the MOP-DOP receptor heteromer form a basis for the development of novel therapeutics for the treatment of pain. In this review, we summarize findings regarding the biological and functional characteristics of the MOP-DOP receptor heteromer and the in vitro and in vivo properties of heteromer-selective ligands.

LINKED ARTICLES

This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2  相似文献   
106.
Within the opioid family of receptors, δ (DOPrs) and μ opioid receptors (MOPrs) are typical GPCRs that activate canonical second-messenger signalling cascades to influence diverse cellular functions in neuronal and non-neuronal cell types. These receptors activate well-known pathways to influence ion channel function and pathways such as the map kinase cascade, AC and PI3K. In addition new information regarding opioid receptor-interacting proteins, downstream signalling pathways and resultant functional effects has recently come to light. In this review, we will examine these novel findings focusing on the DOPr and, in doing so, will contrast and compare DOPrs with MOPrs in terms of differences and similarities in function, signalling pathways, distribution and interactions. We will also discuss and clarify issues that have recently surfaced regarding the expression and function of DOPrs in different cell types and analgesia.

LINKED ARTICLES

This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2  相似文献   
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Oxidative Stress in the Pathogenesis of Hepatic Encephalopathy   总被引:2,自引:0,他引:2  
The pathogenesis of hepatic encephalopathy (HE) remains elusive. While it is clear that ammonia is the likely toxin and that astrocytes are the main target of its neurotoxicity, precisely how ammonia brings about cellular injury is poorly understood. Studies over the past decade have invoked the concept of oxidative stress as a pathogenetic mechanism for ammonia neurotoxicity. This review sets out the arguments in support of this concept based on evidence derived from human observations, animal studies, and cell culture investigations. The consequences and potential therapeutic implications of oxidative stress in HE are also discussed.  相似文献   
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