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411.
Recent studies suggested that prostaglandins (PGs) may play a role in the pathogenesis of retinopathy of prematuriry (ROP). To evaluate if PGs inhibitor, indomethacin, would affect the incidence or severity of the ble-blind controlled study of indomethacin for the closure of PDA. Twenty-three were in the control group and 24 in the indometchin group. Indirect ophthalmospic examinations wee performed from about 4 weeks of postnatal age and onward and needed. There was no significant differences between the groups with respect to birth weight, gestational age, postnatal age, Apgar score, and cardiopulmonary status shortly after birth and at the time of study.Six in the control and 2 in the indomethacin group (p=0.58) developed active ROP; one in each group developed cicatricial ROP. It appears that with current doses of therapy, indomethacin does not increase the incidence or severity of ROP.  相似文献   
412.
Both the original Bethesda system and the current UK classifications of cervical cytology have proved robust but each has a major weakness in the area of abnormalities of uncertain significance. Cytologists recognize that sometimes it is simply impossible to differentiate between reactive and dyskaryotic material. For this reason, the Australian version of the Bethesda system introduced a new category of 'high grade inconclusive' with a recommendation for referral to colposcopy. Approximately 60% of such cases are found to have high grade lesions at colposcopy (Schoolland M, Sterrett G, Knowles S et al .). The present UK system even with the proposed changes requires of the pathologist, a decision as to whether such cases are probably high grade (=a report of moderate dyskaryosis) or not (= a report of borderline). This continues to ignore the fact that sometimes you just cannot tell, even on review. We have taken a consecutive series of 50 referral smears, reported as moderate dyskaryosis, where the histological outcome (by loop cone) is known. These cases were rescreened and then reviewed blind by a pathologist with extensive experience of the Australian NH & MRC modified Bethesda system. On review, the material was reclassified along NH & MRC lines. The results were compared with the biopsy findings in order to determine whether the category of 'inconclusive' might be of value in the context of the NHSCSP.  相似文献   
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The inflammation markers alpha-1-antitrypsin (AAT), Clara cell protein (CC-16), soluble interleukin-2-receptor (IL-R) and the soluble adhesion molecule E-selectin, the intercellular adhesion molecule (ICAM-1) and the vascular adhesion molecule (VCAM-1) were determined in the serum of 195 salt-exposed miners to analyse dose-response relationships between markers and potash dust. Alpha-1-antitrypsin, Clara-cell protein, IL2-R, E-selectin and VCAM-1 were not changed by salt exposure, however the ICAM-1 level in the serum fell slightly as the salt exposure increased. This effect was strongest in the group of smokers, still visible in the group of ex-smokers, no effect was seen in non-smokers. Markers, with the exception of VCAM-1, were influenced by tobacco exposure. Since markers were not elevated in relation to salt dust exposure, the results do not support an inflammatory effect of potash dust on the respiratory system.  相似文献   
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Limited cortisol response to ACTH stimulation has been documented in 22 to 48% of patients with paracoccidioidomycosis (PM). Different approaches to interpret the test and inadequate selection of patients preclude an accurate appraisal of the actual incidence of adrenal insufficiency in PM. Rapid cosyntropin (ACTH) stimulation tests were performed in 38 consecutive patients (9 with the localized and 29 with the disseminated form of PM) and 40 normal controls. Subnormal cortisol responses to ACTH (60 minutes post-ACTH values below 455 nmol/l, 95% confidence limits) were found in only 4 patients (14%) with disseminated PM. If a retrospective sample of 6 patients studied previously (in whom tests were indicated due to clinical suspicion of Addison's disease) were included, or if the absolute cortisol increment above baseline was used for interpretation, we would find figures closer to those previously reported (23 and 24%, respectively). These data reflect that non-systematic evaluation or selection of a substandard criterion to interpret the test overestimates the frequency of adrenocortical insufficiency in PM.  相似文献   
418.
One-carbon metabolism plays a critical role in both DNA methylation and DNA synthesis. Accumulating evidence has shown that interruptions of this pathway are associated with many disease outcomes including cardiovascular diseases and cancers. Mechanistic studies have been performed on genetic polymorphisms involved in one-carbon metabolism. However, expression profiles of these inter-related genes are not well-known. In this study, we examined the gene expression profiles of 11 one-carbon metabolizing genes by quantifying the mRNA level of the lymphocyte among 54 healthy individuals and explored the correlations of these genes. We found these genes were expressed in lymphocytes at moderate levels and showed significant inter-person variations, We also applied principle component analysis to explore potential patterns of expression. The components identified by the program agreed with existing knowledge about one-carbon metabolism. This study helps us better understand the biological functions of one-carbon metabolism.  相似文献   
419.
Alzheimer's disease (AD) is the most common dementia, characterized by pathological accumulation of β-amyloid (Aβ) and hyperphosphorylation of tau protein, together with a damaging chronic inflammation. The lack of effective treatments urgently warrants new therapeutic strategies. Resolution of inflammation, associated with beneficial and regenerative activities, is mediated by specialized pro-resolving lipid mediators (SPMs) including maresin 1 (MaR1). Decreased levels of MaR1 have been observed in AD brains. However, the pro-resolving role of MaR1 in AD has not been fully investigated. In the present study, human monocyte-derived microglia (MdM) and a differentiated human monocyte cell line (THP-1 cells) exposed to Aβ were used as models of AD neuroinflammation. We have studied the potential of MaR1 to inhibit pro-inflammatory activation of Aβ and assessed its ability to stimulate phagocytosis of Aβ42. MaR1 inhibited the Aβ42-induced increase in cytokine secretion and stimulated the uptake of Aβ42 in both MdM and differentiated THP-1 cells. MaR1 was also found to decrease chemokine secretion and reduce the associated increase in the activation marker CD40. Activation of kinases involved in transduction of inflammation was not affected by MaR1, but the activity of nuclear factor (NF)-κB was decreased. Our data show that MaR1 exerts effects that indicate a pro-resolving role in the context of AD and thus presents itself as a potential therapeutic target for AD.  相似文献   
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