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991.
We have demonstrated using immunohistochemistry and in situ hybridization that the calcium-sensing receptor (CaR) is expressed in both villous and extravillous regions of the human placenta. CaR expression was detected in both first trimester and term placentas. In the villous region of the placenta, the CaR was detected in syncytiotrophoblasts and at lower levels in cytotrophoblasts. Local expression of the CaR in the brush border of syncytiotrophoblasts suggests a role for maternal Ca(2+) concentration in the control of transepithelial transport between the mother and fetus. In the extravillous region of the placenta, the CaR was detected in cells forming trophoblast columns in anchoring villi, in close proximity to maternal blood vessels and in transitional cytotrophoblasts. Given the importance of extravillous cytotrophoblasts in the process of uterine invasion and maintenance of placental immune privilege, the CaR represents a possible target by which the maternal extracellular Ca(2+) concentration could promote or maintain placentation. Thus, the results support hypotheses that the CaR contributes to the local control of transplacental calcium transport and to the regulation of placental development.  相似文献   
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Shortages of injectable drugs affect many cancer patients and providers in the U.S. today. Scholars and policymakers have recently begun to devote increased attention to these issues, but only a few tangible resources exist to guide clinical oncologists in developing strategies for dealing with drug shortages on a recurring basis. This article discusses existing information from the scholarly literature, policy analyses, and other relevant sources and seeks to provide practical ethical guidance to the broad audience of oncology professionals who are increasingly confronted with such cases in their practice. We begin by providing a brief overview of the history, causes, and regulatory context of oncology drug shortages in the U.S., followed by a discussion of ethical frameworks that have been proposed in this setting. We conclude with practical recommendations for ethical professional behavior in these increasingly common and challenging situations.  相似文献   
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Jiaqi Huang  Ulrika Zagai  Göran Hallmans  Olof Nyrén  Lars Engstrand  Rachael Stolzenberg‐Solomon  Eric J Duell  Kim Overvad  Verena A Katzke  Rudolf Kaaks  Mazda Jenab  Jin Young Park  Raul Murillo  Antonia Trichopoulou  Pagona Lagiou  Christina Bamia  Kathryn E Bradbury  Elio Riboli  Dagfinn Aune  Konstantinos K Tsilidis  Gabriel Capellá  Antonio Agudo  Vittorio Krogh  Domenico Palli  Salvatore Panico  Elisabete Weiderpass  Anne Tjønneland  Anja Olsen  Begoña Martínez  Daniel Redondo‐Sanchez  Maria‐Dolores Chirlaque  Petra HM Peeters  Sara Regnér  Björn Lindkvist  Alessio Naccarati  Eva Ardanaz  Nerea Larrañaga  Marie‐Christine Boutron‐Ruault  Vinciane Rebours  Amélie Barré  Weimin Ye 《International journal of cancer. Journal international du cancer》2017,140(8):1727-1735
The association between H. pylori infection and pancreatic cancer risk remains controversial. We conducted a nested case‐control study with 448 pancreatic cancer cases and their individually matched control subjects, based on the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, to determine whether there was an altered pancreatic cancer risk associated with H. pylori infection and chronic corpus atrophic gastritis. Conditional logistic regression models were applied to calculate odds ratios (ORs) and corresponding 95% confidence intervals (CIs), adjusted for matching factors and other potential confounders. Our results showed that pancreatic cancer risk was neither associated with H. pylori seropositivity (OR = 0.96; 95% CI: 0.70, 1.31) nor CagA seropositivity (OR = 1.07; 95% CI: 0.77, 1.48). We also did not find any excess risk among individuals seropositive for H. pylori but seronegative for CagA, compared with the group seronegative for both antibodies (OR = 0.94; 95% CI: 0.63, 1.38). However, we found that chronic corpus atrophic gastritis was non‐significantly associated with an increased pancreatic cancer risk (OR = 1.35; 95% CI: 0.77, 2.37), and although based on small numbers, the excess risk was particularly marked among individuals seronegative for both H. pylori and CagA (OR = 5.66; 95% CI: 1.59, 20.19, p value for interaction < 0.01). Our findings provided evidence supporting the null association between H. pylori infection and pancreatic cancer risk in western European populations. However, the suggested association between chronic corpus atrophic gastritis and pancreatic cancer risk warrants independent verification in future studies, and, if confirmed, further studies on the underlying mechanisms.  相似文献   
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