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Spontaneous preterm delivery, prematurity, and low birth weight due to prematurity account for a great part of neonatal morbidity and mortality. Inflammation may cause preterm labor, with the involvement of different mediators that produce diverse aspects of the inflammatory response. Although bacteria are considered to be the main trigger for intrauterine infection/inflammation, immunological factors also appear to be involved. Recently, molecular genetic studies have helped us better understand the underlying pathophysiologic processes. During mammalian pregnancy, maternal–fetal tolerance involves a number of immunosuppressive factors produced by placenta. Recently, placenta-derived exosomes have emerged as new immune regulators in the maternal immune tolerance. This review focuses on the specific immune parameters that become altered during human pregnancy, the identity and function of some immune modulators that have been best characterized to date, as well as a comprehensive evaluation of the pregnancy-associated mechanisms that downregulate proinflammatory immunity to a level sufficient to prevent the triggering of premature common pathway of labor and damage to developing organs.  相似文献   
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ABSTRACT: BACKGROUND: About one-third of adults with diabetes have severe oral complications. However, limited previous research has investigated dental care utilization associated with diabetes. This project had two purposes: to develop a methodology to estimate dental utilization using claims data and to use this methodology to compare utilization of dental care between adults with and without diabetes. METHODS: Data included secondary enrollment and demographic data from Washington Dental Service (WDS) and Group Health Cooperative (GH), clinical data from GH, and dental-utilization data from WDS claims during 2002-2006. Dental and medical records from WDS and GH were linked for enrolees continuously and dually insured during the study. We employed hurdle models in a quasi-experimental setting to assess differences between adults with and without diabetes in 5-year cumulative utilization of dental services. Propensity score matching adjusted for differences in baseline covariates between the two groups. RESULTS: We found that adults with diabetes had lower odds of visiting a dentist (OR=0.74, p < 0.001). Among those with a dental visit, diabetes patients had lower odds of receiving prophylaxes (OR=0.77), fillings (OR=0.80) and crowns (OR=0.84) (p < 0.005 for all) and higher odds of receiving periodontal maintenance (OR=1.24), non-surgical periodontal procedures (OR=1.30), extractions (OR=1.38) and removable prosthetics (OR=1.36) (p < 0.001 for all). CONCLUSIONS: Patients with diabetes are less likely to use dental services. Those who do are less likely to use preventive care and more likely to receive periodontal care and tooth-extractions. Future research should address the possible effectiveness of additional prevention in reducing subsequent severe oral disease in patients with diabetes.  相似文献   
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Background  

The development of evidence-based clinical practice guidelines has gained wide acceptance in high-income countries and reputable international organizations. Whereas this approach may be a desirable standard, challenges remain in low-income settings with limited capacity and resources for evidence synthesis and guideline development. We present our experience using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach for the recent revision of the Kenyan pediatric clinical guidelines focusing on antibiotic treatment of pneumonia.  相似文献   
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