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51.
The association between dummy use and sudden infant death syndrome (SIDS) was investigated in 485 deaths due to SIDS in the postneonatal age group and compared with 1800 control infants. Parental interviews were completed in 87% of subjects. The prevalence of dummy use in New Zealand is low and varies within New Zealand. Dummy use in the two week period before death was less in cases of SIDS than in the last two weeks for controls (odds ratio (OR) 0.76, 95% confidence interval (CI) 0.57 to 1.02). Use of a dummy in the last sleep for cases of SIDS or in the nominated sleep for controls was significantly less in cases than controls (OR 0.44, 95% CI 0.26 to 0.73). The OR changed very little after controlling for a wide range of potential confounders. It is concluded that dummy use may protect against SIDS, but this observation needs to be repeated before dummies can be recommended for this purpose. If dummy sucking is protective then it is one of several factors that may explain the higher mortality from SIDS in New Zealand than in other countries, and may also explain in part the regional variation within New Zealand.  相似文献   
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The primary objective of this study was to assess the expression of MIB‐1 (Ki‐67) in tumour tissues from 808 patients with epithelial ovarian tumours. The second was to evaluate, whether MIB‐1 (Ki‐67) tissue expression levels correlate with clinicopathological parameters and prognosis of the disease. Using tissue arrays (TA), we analysed the MIB‐1 (Ki‐67) expression levels in tissues from 202 women with borderline ovarian tumours (BOT) (177 stage I, 5 stage II, 19 stage III, 1 stage IV) and 606 ovarian cancer (OC) patients (177 stage I, 64 stage II, 311 stage III, 54 stage IV). Using a 10% cut‐off level for MIB‐1 (Ki‐67) overexpression, 12% of the BOTs and 51% of the OCs were positive for MIB‐1 (Ki‐67) expression. The frequency of MIB‐1 (Ki‐67) expression‐positive OC increased with increasing FIGO stage (p = 0.003), increasing histological grade (p ≤ 0.0001), and a significantly different distribution of MIB‐1 (Ki‐67) positive and negative tumours were found in adenocarcinoma NOS, serous adenocarcinomas, mucinous adenocarcinomas, endometrioid adenocarcinomas, non‐epithelial and clear‐cell carcinomas (p = 0.016). Univariate Kaplan–Meier survival analysis performed on all OC cases showed a significant shorter disease specific survival in patients with positive MIB‐1 (Ki‐67) expression in the tumour tissue (p ≤ 0.0001). In a Cox survival analysis including 606 FIGO stages I to IV OC cases, FIGO stage (II vs I: HR = 3.00, 95% CI: 1.81–4.99, III–I: HR = 6.41, 95% CI: 3.90–10.50, IV vs I: HR = 12.69, 95% CI: 7.21–22); age at diagnosis pr.10 years (HR = 1.27, 95% CI: 1.15–1.40), residual tumour after surgery (HR = 1.95, 95% CI: 1.40–2.73) and MIB‐1 (Ki‐67) expression (HR = 1.31, 95% CI: 1.08–1.60) had a significant independent impact on survival. Histological grade (p = 0.14) and histological tumour type (p = 0.35) had no significant independent impact on survival. In conclusion, our results predict that an increased level of MIB‐1 (Ki‐67) expression in tumour tissue, points to a less favourable outcome for OC patients.  相似文献   
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Extracellular adenosine is a physiologically relevant agonist released by various sources, including endothelial cells (EC) and activated platelets, with complex effects mediated via activation of P1 purinergic receptors. Adenosine-induced EC production of glutathione peroxidase1 and nitric oxide is recognized, and an anti-inflammatory mechanism has been described. Effects of extracellular adenosine on the pulmonary EC barrier function and vascular permeability, however, remain poorly characterized. In this study, we demonstrated the adenosine-induced rapid dose-dependent barrier enhancement in human pulmonary artery EC (HPAEC) as measured by an increase in transendothelial electrical resistance (TER). We have shown that HPAEC express only A2A and A2B adenosine receptors. Pharmacological and siRNA depletion studies indicate that A2A, but not A2B receptor activation is required for the adenosine-induced TER increase. Depletion of Gαs with a specific siRNA significantly attenuated the adenosine-induced TER response in HPAEC. In contrast, depletion of either Gαq or Gαi2 did not affect the adenosine-induced TER increase. This suggests that the adenosine-induced TER increase is cAMP-dependent. The adenosine-induced barrier enhancement effects were associated with a rearrangement of the EC F-actin component of the cytoskeleton, enhanced cell-surface presentation of cell–cell junctional protein VE-cadherin and an involvement of Myosin-light-chain phosphatase (MLCP). Our results suggest, for the first time, that adenosine regulates the EC barrier function via A2A receptors followed by Gαs engagement and is associated with cytoskeletal activation.  相似文献   
57.
We investigated the relationship between travel and changes in routine and the sudden infant death syndrome (SIDS) among 485 SIDS cases compared with 1800 randomly selected control infants. There was no increased risk of SIDS with travel. Special events, such as christenings, were not associated with an increased risk of SIDS. However, visits to and by friends or relatives were associated with a significantly reduced risk of SIDS after controlling for potential confounders (odds ratios = 0.70; 95% confidence interval = 0.52, 0.96). These findings may indicate less social support in SIDS cases.  相似文献   
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The paper deals with the relationship of homeostatic and motivational disorders in the postoperative clinical picture in basal-diencephalic tumors. The material included 354 clinical observations of: hypophysial adenoma (n = 135); craniopharyngioma (n = 71); tumors of the third ventricle (n = 88); basal meningiomas (n = 60). A comparative analysis of the findings allowed the authors to support that there are typical variants of changes in the patients' status, which reflect the nature of ion-osmotic disorders. The most significant mental disorders were transient hyperosmolar-hypernatriemic disturbances. The poor predictors were persistent hypernatriemia concurrent with evolving coma, systemic hemodynamic and respiratory disorders. Hyponatriemia is a better predictor of ionosmotic disorders, which requires a careful postoperative monitoring and a comparison of its findings with the specific features of intensive care performed.  相似文献   
60.
To determine whether physical abnormalities in lung surfactant, particularly inversion of the hysteresis between surface tension and surface area, are an effective postmortem marker for sudden infant death syndrome (SIDS).

Methodology:


Bronchoalveolar lavage (BAL) was employed to obtain lung rinsings from 55 infants under 24 months of age at autopsy, comprising 34 index cases and 21 controls. Folch reagent was used to extract the lipoid content which was then applied at two surface concentrations, fixed and BAL-determined (BALD), to the pool of a Langmuir trough in which surface tension (γ) was measured continuously by the Wilhelmy method as surface area ( A ) was cycled.

Results:


The γ: A loops from SIDS samples were inverted relative to controls (i.e. they were hysteresis reversed, this inversion being quantified by an empirical surface tension:area reversal (STAR) score). There was a wide scatter of STAR scores, but a critical value was found which offered a significant ( P = 0.017) separation of SIDS cases from controls for a fixed surface concentration and a highly significant separation ( P = 1.0 × 10-4) for BALD surface concentrations. Differences in the yields of phospholipid and proteolipid, or their correlation to STAR scores, did not reach statistical significance.

Conclusions:


Inversion of the γ: A loops (i.e. hysteresis inversion) would appear to offer a better postmortem marker of SIDS than any reported previously, the procedure having potential for development as a prospective test indicating the risk of this disease.  相似文献   
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