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The major burden of preterm birth is in the developing world, where most of the increasing death and morbidity is secondary to infectious diseases such as malaria, HIV, tuberculosis, bacterial vaginosis and intestinal parasites. In some developing countries, the growth of medical care has outstripped the growth of preventive public health, with an associated increase in iatrogenic preterm births. In developed countries, more than one-third of preterm births are medically indicated because of conditions such as fulminating pre-eclampsia or severe intrauterine growth restriction. Neither of these conditions is currently preventable. One in five preterm births is associated with multiple pregnancy, and these have been greatly increased by assisted reproduction techniques. The use of tocolytics has proved disappointing perhaps because inflammation rather than spontaneous uterine activity is increasingly recognised as the final common pathway. Inappropriate antibiotics used late in pregnancy are ineffective and may have adverse effects. Currently, the most promising interventions are public health related and include reducing the transmission of communicable diseases, improvements in the management of diabetes and reduction in harmful behaviours such as smoking and drug abuse.  相似文献   
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Tick-borne diseases are a serious threat to both public and veterinary health. In this study, we used high-throughput sequencing to characterize the virome of three tick species implicated in the spread of vector-borne disease throughout Croatia. Ten viruses were identified, including seven potential novel species within the viral families Flaviviridae, Nyamiviridae, Rhabdoviridae, Peribunyaviridae, Phenuiviridae, and Nairoviridae.  相似文献   
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With use of a unique data set from the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute for 11,062 women diagnosed with ovarian cancer from 1973 to 1982, this study focuses on the impact of old age on this malignancy. Aspects of ovarian cancer as it pertains especially to elderly women (those 65 years or older) are examined according to age/stage relationships at initial diagnosis and age variations in treatment and survival. Elderly women are more likely than younger women to be in advanced stages of ovarian cancer at initial diagnosis, and they constitute about 42% of this group. In the stage-unknown category, over 50% are 65 years or older. Data suggest that elderly women are treated more conservatively than younger patients. The National Cancer Institute data also illustrate the increased preference to treat this neoplasm with surgical procedures and chemotherapy rather than surgical procedures and radiation. For Stages III and IV disease, 5-year relative survival rates for elderly women are almost one half of the rate observed for women under 65. Although the prognosis of patients with advanced ovarian tumors is poor for all, it is even worse as age progresses.  相似文献   
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Alcoholic liver cirrhosis is a leading cause of morbidity and mortality in alcohol dependence. A common precursor to cirrhosis is alcoholic hepatotoxicity evident clinically by elevated serum liver enzymes. In this study 50 male patients with significant (greater than two times upper limits of normal) elevation of liver enzymes attending a veterans inpatient alcohol treatment center were matched by age and time since last drink to 50 male veterans without elevated liver enzymes. Patients with elevated liver enzymes were found to be more likely to be daily drinkers, less likely to indulge in binge drinking patterns or have alcoholic blackouts, and showed a trend towards a less severe pattern of alcoholism. Significant gamma glutamyl transferase (GGT) elevations were found in patients consuming an average of 7 beers/day for 5 years, and significant aspartate aminotransferase (AST) elevations were found in patients consuming a threshold of 12 beers/day for 10 years. These findings are consistent with current research suggesting alcoholic cirrhosis is a result of a threshold exposure to alcohol in alcoholics with an additional environmental or genetic risk factor.  相似文献   
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Objective  To assess the effects of aromatase inhibitors in women symptomatic of pain with endometriosis.
Design  A systematic review of published literature.
Material and methods  We conducted a comprehensive literature search to identify all the published observational and randomised studies evaluating the efficacy of aromatase inhibitors on pain associated with endometriosis. A combination of keywords was used to identify the maximum number of relevant citations in MEDLINE, EMBASE, CINAHL and the Cochrane Database.
Outcome  Pain relief, lesion size and quality of life.
Results  There were eight studies (137 women) evaluating outcomes of aromatase inhibitors. In case series/reports (seven studies, 40 women), aromatase inhibitors combined with progestogens or oral contraceptive pill or gonadotrophin-releasing hormone (GnRH) analogues reduced mean pain scores and lesion size and improved quality of life. An RCT (97 women) demonstrated that aromatase inhibitors in combination with GnRH analogues significantly improved pain ( P < 0.0001) compared with GnRH analogues alone together with significant improvement in multidimensional patient scores ( P < 0.0001). There was no significant reduction in spine or hip-bone densities.
Conclusion  Aromatase inhibitors appear to have a promising effect on pain associated with endometriosis, but the strength of this inference is limited due to a dearth of the evidence available.  相似文献   
68.
Polycystic ovary syndrome (PCOS), insulin resistance and overall mortality due to diabetes and coronary artery disease are higher in South Asians than in Caucasians. Aims: We compared the prevalence of the C677T and A1298C single nucleotide polymorphisms in the methylenetetrahydrofolate reductase gene in South Asian and Caucasian women, its association with folate and homocysteine (Hcy) metabolism, and its relevance to future atherogenic events. Methods and results: 71 women were recruited for the study: South Asian PCOS (21) plus controls (9) and Caucasian PCOS (25) plus controls (16). Anthropometric and laboratory parameters were compared. South Asian PCOS women were significantly hyperandrogenic and exhibited a greater degree of insulin resistance. Caucasian PCOS women had higher plasma Hcy concentrations with a 1.9 times higher frequency of the T allele than the South Asian PCOS group. In the presence of this variant allele, plasma Hcy levels appear to be higher in both PCOS groups. The South Asians had a 1.8 times higher frequency of the C allele than the Caucasians; however, the overall frequency was comparable in the two PCOS groups. The frequency of homozygosity, i.e. TT677 and CC1298, was 7.2% and 4.9% in the Caucasians and 0% and 16.6% in the South Asian recruits, respectively. Dietary inadequacies in the South Asian women can influence their plasma folate and B12 concentrations resulting in hyperhomocysteinemia which, in combination with dyslipidaemia and insulin resistance, can lead to long-term atherogenic consequences. CONCLUSIONS: Current data suggests that the mechanisms of atherothrombosis have separate pathways in the two ethnic groups. Larger studies exploring the current theme need to be carried out in the PCOS groups to obtain adequate insight.  相似文献   
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Background and objectives: Vitamin D and folate are highly UV sensitive, and critical for maintaining health throughout the lifecycle. This study examines whether solar irradiance during the first trimester of pregnancy influences vitamin D receptor (VDR) and nuclear folate gene variant occurrence, and whether affected genes influence late-life biochemical/clinical phenotypes.Methodology: 228 subjects were examined for periconceptional exposure to solar irradiance, variation in vitamin D/folate genes (polymerase chain reaction (PCR)), dietary intake (food frequency questionnaire (FFQ)) and important adult biochemical/clinical phenotypes.Results: Periconceptional solar irradiance was associated with VDR-BsmI (P = 0.0008wk7), TaqI (P = 0.0014wk7) and EcoRV (P = 0.0030wk6) variant occurrence between post-conceptional weeks 6–8, a period when ossification begins. Similar effects were detected for other VDR gene polymorphisms. Periconceptional solar irradiance was also associated with 19 bp del-DHFR (P = 0.0025wk6), and to a lesser extent C1420T-SHMT (P = 0.0249wk6), a folate-critical time during embryogenesis. These same genes were associated with several late-life phenotypes: VDR-BsmI, TaqI and ApaI determined the relationship between dietary vitamin D and both insulin (P < 0.0001/BB, 0.0007/tt and 0.0173/AA, respectively) and systolic blood pressure (P = 0.0290/Bb, 0.0299/Tt and 0.0412/AA, respectively), making them important early and late in the lifecycle. While these and other phenotype associations were found for the VDR variants, folate polymorphism associations in later-life were limited to C1420T-SHMT (P = 0.0037 and 0.0297 for fasting blood glucose and HbA1c levels, respectively). We additionally report nutrient–gene relationships with body mass index, thiol/folate metabolome, cognition, depression and hypertension. Furthermore, photoperiod at conception influenced occurrence of VDR-Tru9I and 2R3R-TS genotypes (P = 0.0120 and 0.0360, respectively).Conclusions and implications: Findings identify environmental and nutritional agents that may interact to modify gene–phenotype relationships across the lifecycle, offering new insight into human ecology. This includes factors related to both disease aetiology and the evolution of skin pigmentation.  相似文献   
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