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BackgroundCampylobacter spp. are one of the commonest causes of diarrhea in children under five and in resource poor settings also lead to malabsorption and stunting. The purpose of this systematic review was to understand the burden of Campylobacter spp. associated diarrhea among children in the South Asian countries.MethodsThis systematic review followed the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analysis) guidelines. Databases were searched with defined keywords for publications from the years 1998–2018. Data on proportion of positive samples was extracted to compare the rates of Campylobacter infection among children (under the age of 19) from different study populations.ResultsOf the 359 publications screened, 27 eligible articles were included in this systematic review and categorized based on study design. In 8 case-control studies, Campylobacter spp. was detected more frequently among diarrheal cases (range, 3.2–17.4%) than non-diarrheal cases (0–13%). Although there were variations in the study population, overall, children under the age of two years experienced Campylobacter diarrhea more often than older children. Most studies reported stool culture as the method used to detect Campylobacter spp. however retesting using PCR-based methods significantly increased detection rates. Limited data were available on Campylobacter species. In 4 studies that provided species data, C. jejuni (3.2–11.2%) was shown to be the most common species, followed by C. coli.ConclusionIn South Asia, Campylobacter spp. are one of the most common bacterial diarrheal pathogens affecting children but there is a paucity of data on species, risk factors and attributable sources. Although a few studies were available, the epidemiology of campylobacteriosis remains uncertain. To understand the true burden and sources of infection, more detailed studies are needed collecting data from human, animal and environmental sources and using both culture and genomic tools.  相似文献   
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Introduction

Stereotactic body radiation therapy (SBRT) is a promising curative treatment for early-stage NSCLC. It is unclear if survival outcomes for SBRT are influenced by a lack of pathological confirmation of malignancy and staging of disease in these patients. In this systematic review and meta-analysis, we assess survival outcomes after SBRT in studies with patients with clinically diagnosed versus biopsy-proven early-stage NSCLC.

Methods

The main databases were searched for trials and cohort studies without restrictions to publication status or language. Two independent researchers performed the screening and selection of eligible studies. Outcomes were overall survival, cancer-specific survival, and disease-free survival. The inverse variance method and the random effects method for meta-analysis were used to assess pooled survival estimates.

Results

A total of 11,195 nonduplicate records were identified by the original search strategy. After screening by title and abstract, 1051 potentially eligible records were identified. A total of 43 articles were included. The comparative studies showed lower 3-year overall survival and lower 2-year and 5-year cancer-specific survival for biopsy-proven disease compared to clinical disease. However, 5-year overall survival was the same for both groups. For the pooled estimates, 3-year disease-free survival and 2-year cancer-specific survival were lower for biopsied disease.

Conclusions

Results of this systematic review and meta-analysis show a discrepancy in oncological outcomes for patients undergoing SBRT for suspected early-stage NSCLC in whom there is pathologic conformation of malignancy and those who there is only a clinical diagnose of NSCLC. These results emphasize the importance of obtaining pathologic proof of malignancy.  相似文献   
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Background: Depression and anxiety are common in cancer and antidepressants (AD) are efficacious treatment. The relationship between AD adherence and mortality in cancer is unclear. This study aimed to evaluate the association between adherence to AD and all‐cause mortality in a population‐based cohort of patients with cancer. Materials and Methods: We conducted a 4‐year historical prospective cohort study including 42,075 patients with cancer who purchased AD at least once during the study period. Adherence to AD was modeled as nonadherence (<20%), poor (20–50%), moderate (50–80%), and good (>80%) adherence. We conducted multivariable survival analyses adjusted for demographic and clinical variables that may affect mortality. Results: During 1,051,489 person‐years at risk follow‐up, the adjusted hazard ratios (HR) for mortality were 0.89 (95% confidence interval [CI]: 0.83–0.95), 0.77 (95% CI: 0.66–0.72), and 0.80 (95% CI: 0.76–0.85) for the poor, moderate, and good adherence groups, respectively, compared to the nonadherent group. Analysis of the entire sample and a subgroup with depression, for cancer subtypes, revealed similar patterns for breast, colon, lung, and prostate cancers, but not for melanoma patients. Multivariate predictors of premature mortality included male gender (HR 1.48 [95% CI: 1.42–1.55]), current/past smoking status (HR 1.1, [95% CI: 1.04–1.15]; P < .0001), low socioeconomic status (HR 1.1, [95% CI: 1.03–1.17]; P < .0001) and more physical comorbidities. Conclusions: The present study is the first to demonstrate that higher adherence to AD is associated with a decrease of all‐cause mortality in a large nationwide cohort of cancer patients. Our data add to the pressing need to encourage adherence to AD among cancer patients.  相似文献   
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A numerical-based model was developed and implemented to determine the spatial and temporal temperature distributions within skin tissue resulting from thermal contact with a heated and high thermal conductivity metallic medium. In the presence of wet tissue, boiling is likely to occur, thereby affecting the probability of inducing burns. This investigation deals with how contact between a hot, highly conductive metallic material and skin gives rise to burns. In particular, the study focuses on the likelihood that metals typically used in cooking or industrial applications may cause burns. Insofar as the surfaces under consideration are above the boiling temperature of water, a mathematical model including phase change was developed. That model allowed different thermophysical properties to be respectively employed for dry and wet tissues.Multiple processes and their governing parameters were investigated to assess their impact on burn severity, including the temperature of the metal, the duration of contact, the contact resistance between the surface and the skin, the temperature range over which phase change occurred, and the cooling environment after the exposure. It was discovered that the most important parameters are the surface temperature and exposure duration. The other conditions/parameters had lesser impacts on the results.  相似文献   
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