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141.
Human placental lactogen (HPL) was measured in 525 serum samples from 144 pregnant women and related to smoking habits and the birth weight of their infants. Women smoking during pregnancy were found to have a level of HPL significantly lower than the non-smokers (p less than 0.05). A significant correlation between HPL and birth weight was found (r=0.38); p less than 0.001) which remained significant when smoking was held constant (r=0.35; p less than 0.001). There was no relationship between birth weight and smoking when HPL was held constant.  相似文献   
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Skin functions as a first line of defense against microbial invasion. Tissue-engineered cultured skin substitutes (CSS) are used to aid wound closure in massively burned patients, and have been used to facilitate safe and effective wound closure in adult patients with chronic wounds. Although they contain only two cell types at grafting, they can potentially contribute to innate defense against pathogens and stimulation of adaptive immunity. Gene microarrays were used to identify expression in cultured skin of genes involved in innate and adaptive immune responses, and to evaluate the effects of cytokine stimulation on expression levels. Cultured skin expressed multiple antimicrobial protein genes, including human β defensins 1 and 2 and S100A12. In addition, the antiviral gene APOBEC3G, which was not previously identified in skin, was expressed in CSS and up-regulated by interleukin-1α and tumor necrosis factor α. Cathelicidin was not expressed in unstimulated CSS, but was induced by cytokine treatment. Further, genes encoding several proinflammatory cytokines and members of the toll-like receptor and nuclear factor κ B pathways were expressed in CSS, suggesting that cells in CSS can mediate activation of inflammatory responses. The observed expression patterns indicate that engineered human skin utilizes innate defense mechanisms similar to those reported for native skin. Therefore, regulation of these pathways by cytokine stimulation may offer a mechanism for increasing innate immunity in CSS to combat wound infection after grafting onto patients.  相似文献   
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Fourteen women performed treadmill exercise for continuous 10-minute periods at levels of 2, 3 and 4 mets in the second and third trimester of pregnancy and again postpartum. The percentage increase in heart rate in response to exercise was similar during pregnancy and postpartum while systolic blood pressure was increased only during pregnancy. Maternal plasma noradrenaline levels at peak exercise increased 64% (p less than 0.005), 42% (p less than 0.005) and 29% (NS) in the 3 studies respectively compared to resting levels at these times. Ten women experienced increased uterine activity during the exercise or recovery periods. Fetal heart rate was increased (p less than 0.05) by exercise but this was independent of uterine contractions and plasma noradrenaline levels.  相似文献   
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To investigate the distribution and specificity of intestinal metaplasia (IM) in columnar lined esophagus (CLE), the authors reviewed biopsies of the hiatal hernia pouch (HHP) and esophagus from 17 patients with CLE (84 biopsies) and 10 controls (25 biopsies). The proximal margin of the gastric folds was used as an endoscopic landmark, corresponding to the gastroesophageal muscular junction (GEMJ). No biopsies obtained above the GEMJ in control patients showed columnar mucosa. No goblet cell metaplasia was seen in 21 biopsies of the HHP from patients with CLE or in 13 corresponding biopsies from controls. In contrast, alcian blue (AB) stains showed diffuse acid mucins in 3 of 21 biopsies of the HHP from patients with CLE and in 10 of 13 corresponding biopsies from controls, demonstrating that goblet cell metaplasia clearly distinguishes biopsies of CLE from the HHP (P less than 0.01), whereas small amounts of diffuse acid mucin on AB stains do not. IM evidenced by goblet cell metaplasia was frequently seen in biopsies only 2-3 cm above the GEMJ, and CLE was limited to that area in three patients, suggesting that the distal esophagus cannot be dismissed as a site for metaplastic and possibly premalignant mucosa. Adenocarcinoma was diagnosed during the course of the study in one patient with only 5 cm of columnar mucosa above the GEMJ.  相似文献   
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