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Municipal water sources in India have been found to be highly contaminated, with further water quality deterioration occurring during household storage. Quantifying water quality deterioration requires knowledge about the exact source tap and length of water storage at the household, which is not usually known. This study presents a methodology to link source and household stored water, and explores the effects of spatial assumptions on the association between tap-to-household water quality deterioration and enteric infections in two semi-urban slums of Vellore, India. To determine a possible water source for each household sample, we paired household and tap samples collected on the same day using three spatial approaches implemented in GIS: minimum Euclidean distance; minimum network distance; and inverse network-distance weighted average. Logistic and Poisson regression models were used to determine associations between water quality deterioration and household-level characteristics, and between diarrheal cases and water quality deterioration. On average, 60% of households had higher fecal coliform concentrations in household samples than at source taps. Only the weighted average approach detected a higher risk of water quality deterioration for households that do not purify water and that have animals in the home (RR = 1.50 [1.03, 2.18], p = 0.033); and showed that households with water quality deterioration were more likely to report diarrheal cases (OR = 3.08 [1.21, 8.18], p = 0.02). Studies to assess contamination between source and household are rare due to methodological challenges and high costs associated with collecting paired samples. Our study demonstrated it is possible to derive useful spatial links between samples post hoc; and that the pairing approach affects the conclusions related to associations between enteric infections and water quality deterioration.  相似文献   
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Studies in adult HT have demonstrated improved cardiac function in the recipient following administration of T3 to the donor. The purpose of this experiment was to assess the effects of T3 on the function of the immature donor heart following HT in a piglet model. A total of 32 piglets were divided into 16 donors and 16 recipients. Following creation of brain death, half of the donor piglets were randomized to receive three doses of T3 (0.2 μg/kg) along with hydrocortisone (1 mg/kg). The donor hearts were then transplanted into the recipient piglets on CPB. Duration of survival off CPB, inotrope score, and EF of heart following CPB were evaluated. There were no differences between the two groups in age, weight, pre‐brain death EF, T3 levels, and CPB times. Post‐CPB survival times were inversely related to the ischemic times in both groups (Pearson r=?0.80, P<.001), and this relationship was not influenced by T3. There was no difference in inotrope score, EF, or biochemical assessment between the two groups. Administration of T3 in combination with hydrocortisone to the brain‐dead donor confers no beneficial effect on myocardial function or survival following HT in a piglet model.  相似文献   
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Two sequential hepatitis B virus (HBV) strains obtained before and during an icteric flare-up of an occult HBV infection in a patient coinfected with human immunodeficiency virus revealed HBV surface antigen (HBsAg) test escape mutations, although the patient had never received hepatitis B-specific immunoglobulin. In contrast to the high HBV DNA loads, recurrence of HBsAg, and resulting icteric hepatitis, phenotypic analysis of the mutated HBV strains revealed significantly reduced replication efficacies in vitro, compared with wild-type HBV. Therefore, immune escape in the transiently anti-HBs-positive patient appeared to be crucial for persistence and reactivation. Immune escape mutants evolved even without exogenous selective pressure, hampered detection in HBsAg screening, and might be transmitted during reactivation with high HBV loads.  相似文献   
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14-Aminocamptothecins were synthesized in good yields by treating camptothecin (1a) and 7-ethylcamptothecin (1b) with 90% fuming nitric acid either neat or in acetic anhydride and then followed by reduction of the resulting 14-nitrocamptothecins (2). 14-Aminocamptothecin (3a) and 7-ethyl-14-aminocamptothecin (3b) demonstrated excellent cytotoxic potency against human tumor cell lines in vitro, and they are not substrates for any of the major clinically relevant efflux pumps (MDR1, MRP1, and BCRP). 3a and 3b showed similar cytotoxicity against human and mouse bone marrow progenitor cells. This is in contrast to many camptothecin analogues, which are substrates for efflux pumps and are dramatically more toxic to human marrow cells relative to murine. 3a and 3b demonstrated significant brain penetration when dosed orally in mice. 3b showed significantly better efficacy relative to topotecan when dosed orally in the three ectopic xenograft models, H460, HT29, and PC-3. On the basis of its favorable in vitro and in vivo profile, 3b warrants future development.  相似文献   
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Background

Citation analysis provides insights into the history and developmental trajectory of scientific fields. Our objective was to perform an analysis of citation classics in the journals of pediatric specialty and to examine their characteristics.

Methods

Initially, all the journals listed under the category of pediatrics (n = 120) were identified using Journal Citation Reports. Web of science database was then searched (1950–2016) to select the top-100 cited articles in the above identified pediatric journals. The top-100 cited article were categorized according the study design, sub-specialty, country, institutional affiliation, and language.

Results

The top-100 articles were published in 18 different journals, with Pediatrics having the highest numbers (n = 40), followed by The Journal of Pediatrics (n = 17). The majority (n = 62) of classics were published after 1990. The most cited article had citation count of 3516 and the least cited had a citation count of 593. The USA (n = 71) was the most commonly represented country, and 60 institutions contributed to 100 articles. Fifteen authors contributed to more than one classic as first or second author. Observational study (n = 55) was the commonest study design across all decades, followed by reviews (n = 12), scale development studies (n = 11), and guidelines (n = 11). Among the pediatric sub-specialties, growth and development articles were highly cited (n = 24), followed by pediatric psychiatry and behavior (n = 21), endocrinology (n = 15), and neonatology (n = 12).

Conclusions

The top-100 cited articles in pediatrics identify the impactful authors, journals, institutes, and countries. Observational study design was predominant—implying that inclusion among citation classics is not related to soundness of study design.
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