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91.
The aim of the present study was to evaluate pregnancy-related changes in autonomic regulatory functions in healthy subjects. We studied cardiovascular autonomic responses to head-up tilt (HUT) in 28 pregnant women during the third trimester of pregnancy and 3 months after parturition. The maternal ECG and non-invasive beat-to-beat blood pressure were recorded in the horizontal position (left-lateral position) and during HUT in the upright position. Stroke volume was assessed from blood pressure signal by using the arterial pulse contour method. Heart rate variability (HRV) was analysed in frequency domain, and baroreflex sensitivity by the cross-spectral and the sequence methods. In the horizontal position, all frequency components of HRV were lower during pregnancy than 3 months after parturition (P < 0.01 to <0.001), while pregnancy had no influence on normalized low frequency and high frequency powers. During pregnancy haemodynamics was well balanced with only minor changes in response to postural change while haemodynamic responses to HUT were more remarkable after parturition. In pregnant women HRV and especially its very low frequency component increased in response to HUT, whereas at 3 months after parturition the direction of these changes was opposite. Parasympathetic deactivation towards term is likely to contribute to increased heart rate and cardiac output at rest, whereas restored sympathetic modulation with modest responses may contribute stable peripheral resistance and sufficient placental blood supply under stimulated conditions. It is important to understand cardiovascular autonomic nervous system and haemodynamic control in normal pregnancy before being able to judge whether they are dysregulated in complicated pregnancies.  相似文献   
92.
The genetic variation of apolipoprotein B has been studied extensively in Finns with the aid of protein and DNA polymorphisms. Population association studies confirmed significant associations between the XbaI polymorphism of the apolipoprotein B gene and elevated serum cholesterol levels, and dietary studies suggested that the XbaI and ins/del polymorphisms might modify the serum lipid response to dietary fat intake. Studies comparing patients and controls, however, did not confirm previous studies suggesting that the multi-allelic variation at the 3'VNTR region of the apolipoprotein B gene was associated with coronary artery disease. The results suggest that the apolipoprotein B gene is involved in the regulation of serum lipid levels. A yet unknown mutation in linkage disequilibrium with the XbaI site may contribute to this regulation.  相似文献   
93.
AbstractObjective: To obtain a deeper understanding of smokers' feelings and to establish co-operative networking groups,the opinions about smoking cessation of health careprofessionals and smokers were studied.Design: Focus group discussions were held in order to gainideas and tools to be used in smoking cessation work, inparticular in network groups. Two focus group discussions forhealth care professionals (n = 7) and one focus groupdiscussion for ex-smokers/smokers (n = 3) were held.Results: The study suggests that problems exist in smokingcessation work among health care professionals. The mainissues among the health care professionals were lack ofmotivation and consistency of approach. Informationconcerning the health risk related to smoking no longerreaches people. New ways of health promotion are desired.Smokers feel that lack of positive support and nicotinedependence are the main problems in their attempts to quit.Conclusions: Society and smokers have the same goal:smoking cessation. However, both parties do not seem toagree on ways of achieving this goal. A local network amonghealth care professionals could motivate and give rise to newmethods of smoking cessation counselling. Positive supportand nicotine replacement therapy could significantlyimprove smokers' success rates. Trained personnel havebetter opportunities for meeting smokers and that is whycessation should be part of the core curriculum and basictraining for health care professionals.  相似文献   
94.
We studied IgG antibody levels to synthetic peptides (p62, E11 and E3) from Epstein-Barr nuclear antigen-1 (EBNA-1) protein sequence in sera of patients with rheumatoid arthritis (RA), in pre-RA and in rheumatoid factor (RF) positive non-RA sera from Finland. Anti-E11 and anti-E3 antibody levels were significantly elevated in RA sera, compared with both RF negative and RF positive nonrheumatoid controls. The concentrations of anti-E11 and anti-E3 antibodies in the preillness sera were lower than those in RA sera. Eight-year followup samples of patients with RA had slightly decreased levels of anti-E3 and anti-E11 antibodies compared with samples taken within 6 months of the disease onset. Anti-p62 antibody levels did not differ significantly between any of the groups studied. Thus, elevated levels of antibodies to 2 of the glycine containing EBNA-1 peptides were associated with clinical RA.  相似文献   
95.
Dietary fibre has been proposed to decrease risk for colon cancer by altering the composition of intestinal microbes or their activity. In the present study, the changes in intestinal microbiota and its activity, and immunological characteristics, such as cyclo-oxygenase (COX)-2 gene expression in mucosa, in pigs fed with a high-energy-density diet, with and without supplementation of a soluble fibre (polydextrose; PDX) (30 g/d) were assessed in different intestinal compartments. PDX was gradually fermented throughout the intestine, and was still present in the distal colon. Irrespective of the diet throughout the intestine, of the four microbial groups determined by fluorescent in situ hybridisation, lactobacilli were found to be dominating, followed by clostridia and Bacteroides. Bifidobacteria represented a minority of the total intestinal microbiota. The numbers of bacteria increased approximately ten-fold from the distal small intestine to the distal colon. Concomitantly, also concentrations of SCFA and biogenic amines increased in the large intestine. In contrast, concentrations of luminal IgA decreased distally but the expression of mucosal COX-2 had a tendency to increase in the mucosa towards the distal colon. Addition of PDX to the diet significantly changed the fermentation endproducts, especially in the distal colon, whereas effects on bacterial composition were rather minor. There was a reduction in concentrations of SCFA and tryptamine, and an increase in concentrations of spermidine in the colon upon PDX supplementation. Furthermore, PDX tended to decrease the expression of mucosal COX-2, therefore possibly reducing the risk of developing colon cancer-promoting conditions in the distal intestine.  相似文献   
96.
The role of intakes of different sugars in the development of type 2 diabetes was studied in a cohort of 4,304 men and women aged 40-60 y and initially free of diabetes at baseline in 1967-1972. Food consumption data were collected using a dietary history interview covering the habitual diet during the previous year. The intakes of different sugars were calculated and divided in quartiles. During a 12-y follow-up, 177 incidents of type 2 diabetes cases were identified from a nationwide register. Combined intake of fructose and glucose was associated with the risk of type 2 diabetes but no significant association was observed for intakes of sucrose, lactose, or maltose. The relative risk between the highest and lowest quartiles of combined fructose and glucose intake was 1.87 (95% [CI] = 1.19, 2.93; P = 0.003). The corresponding relative risks between the extreme quartiles of consumption of food items contributing to sugar intakes were 1.69 (95% [CI] = 1.17, 2.43; P < 0.001) for sweetened berry juice and 1.67 (95% [CI] = 0.98, 2.87; P = 0.01) for soft drinks. Our findings support the view that higher intake of fructose and glucose and sweetened beverages may increase type 2 diabetes risk.  相似文献   
97.
目的 比较乳腺癌改良根治术后容积调强弧形治疗(VMAT)与调强放疗(IMRT)对计划靶区(PTV)和危及器官(OAR)的剂量学差异,为临床提供循证学依据。方法 根据纳入和排除标准,计算机检索PubMed、Cochrane Library、FMRS、中国知网、万方数据库及维普全文期刊数据库,筛选所有乳腺癌改良根治术后VMAT与IMRT剂量学比较的文献纳入研究。检索时间从建库至 2020年3月。应用Stata14.0软件进行Meta分析结果 13项研究的 281例纳入Meta分析。与IMRT计划相比,VMAT计划明显提高PTV剂量 (D95%,P<0.001),明显改善PTV剂量均匀性(P<0.001)和适形性(P=0.004)。VMAT计划较IMRT计划有效降低患侧 肺V20Gy (P=0.027)和健侧 肺V10Gy (P=0.003);而患侧肺 Dmean、V5Gy、V10Gy、V30Gy,健侧肺 Dmean、V5Gy,心脏 Dmean、V10Gy、V30Gy两组计划均相近(均 P>0.05)。IMRT计划较VMAT计划降低心 脏V5Gy (P=0.001),但对心 脏V5Gy纳入文献进行敏感性分析,显示结果稳定性较差。VMAT计划比IMRT计划明显减少治疗时间(P<0.001)和机器跳数(P<0.001)。结论 乳腺癌改良根治术后放疗中VMAT比IMRT在靶区剂量覆盖、均匀性和适形性,对患侧肺和健侧肺保护,以及治疗效率方面均更具剂量学优势。  相似文献   
98.
Ribavirin is an approved broad-spectrum antiviral drug. A liver-targeting prodrug of ribavirin, viramidine, is in clinical trial in an attempt to provide a better therapeutic index. The conversion of viramidine to ribavirin, and of ribavirin to an inactive metabolite through adenosine deaminase, is reported. Kinetic analysis indicates that adenosine deaminase is likely involved in activation of viramidine in vivo, and the process is highly pH sensitive. The differential activities of two consecutive deamination reactions are kinetically studied and interpreted based on adenosine deaminase structural information. A comprehensive understanding of the viramidine and ribavirin deamination mechanism should help in designing better nucleoside therapeutics in the future.  相似文献   
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