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41.
AIM: We examined the impact of advanced maternal age (>40 years old) on the survival of twin small-for-gestational-age (SGA) infants, that is, infants who were smaller in size than was expected for the baby's sex, genetic heritage, and gestational age. METHODS: The present study was a retrospective cohort study on twin live births in the USA from 1995 to 1998 inclusive. Two categories of SGA babies were defined: discordant (when only one of a twin pair was SGA) and concordant (when both were SGA). Otherwise, the twin pair was appropriate-for-gestational-age (AGA) concordant. RESULTS: 192,195 twin pairs were analyzed. The incidence of SGA discordance and concordance was 11.8% and 3.9%, respectively. The occurrence of both SGA subtypes tended to decrease with increasing maternal age. The unadjusted risk for neonatal mortality increased when both twins were affected (15.8: 22.8 and 56.6 per 1000 among AGA concordant, SGA discordant and SGA concordant twins; P-value for trend < 0.0001). Using maternal-age-specific AGA babies as reference, the adjusted risk for neonatal mortality climbed progressively with advancing maternal age in a dose-dependent pattern, being lowest among teenagers and highest in mothers aged > or =40 years. CONCLUSIONS: SGA discordance and concordance declined with advancing maternal age. In contrast, neonatal mortality of both SGA subtypes worsened with the increase in maternal age compared with that of the age-specific AGA infants. These findings are potentially useful to care providers in counseling older women, a group that is progressively increasing in size and is most susceptible to twining.  相似文献   
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为探讨用腺病毒载体携带PML(PromyelocyticLeukemia)基因作为前列腺癌基因治疗的可能性,应用重组人携带PML基因腺病毒(AdPML)感染培养的前列腺癌细胞,观察表达PML蛋白的癌细胞与对照组癌细胞的体外生长和裸鼠体内致瘤能力变化,对荷瘤裸鼠瘤体周围注射AdPML,观察治疗组和对照组肿瘤生长的变化。结果显示,感染AdPML的前列腺癌细胞体外生长和裸鼠体内致瘤能力明显下降,荷瘤裸鼠瘤体周围注射AdPML后肿瘤生长速度明显减慢。证实了PML是一种生长抑制因子,提示其可能被应用于前列腺癌的基因治疗研究  相似文献   
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The scientific community is charged with growing demands regarding the management of project data and outputs and the dissemination of key results to various stakeholders. We discuss experiences and lessons from CONTRAST, a multidisciplinary alliance that had been funded by the European Commission over a 4-year period, in order to optimize schistosomiasis control and transmission surveillance in sub-Saharan Africa. From the start, project partners from Europe and Africa set out an ambitious goal: to sample data following standard protocols at all field sites and then sharing the data in a way that would enable all project partners to have access through a password-protected Internet-based data portal. This required anonymous agreement on several common standardized sample forms, ranging from the mundane but important issue of using the same units of measurement to more complex challenges, for instance agreeing on the same protocols for double-treatment of praziquantel in different settings. With the experiences gained by the CONTRAST project, this paper discusses issues of data management and sharing in research projects in the light of the current donor demand, and offers advice and specific suggestions for similar interdisciplinary research projects.  相似文献   
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Data on the bacteriological findings, diagnostic measures and clinical course of 875 patients with bacterial meningitis are presented. Findings from the medical records and from a follow-up questionnaire survey of 667 of these cases revealed no significant difference between patients treated with antibiotics before admission (pretreated) and those who were not treated before admission (non-pretreated) with respect to clinical condition on admission, mortality and late sequelae. Pretreatment was, however, associated with a longer duration of symptoms. Apart from cases due to Neisseria meningitidis, there were no significant differences in diagnostic findings between pretreated and non-pretreated cases. In the group of pretreated meningococcal patients, however, positive blood cultures, pleiocytosis in the cerebrospinal fluid (CSF) and positive cultures from sites other than blood and CSF were less frequent than in the non-pretreated cases.  相似文献   
46.
OBJECTIVE: Surgical cure of Cushing's syndrome (CS) is followed by adrenocortical insufficiency, which may be long-lasting. The aim was to elucidate recovery of adrenocortical function, defined as a normal cortisol response to ACTH stimulation, and the relation to ACTH in patients cured for CS due to pituitary Cushing's disease (CD) or adrenal (AA) adenomas. DESIGN: A retrospective study including 32 patients considered surgically cured for CS (18 CD, 14 AA). RESULTS: Twelve (67%) patients with CD recovered within median 24 months (range 7 months-4(1)/(2) years) whereas six did not recover within 3-12 years. Plasma ACTH (p-ACTH) at time of recovery was not different from p-ACTH in patients not recovering (P = 0.9). Eleven (79%) patients with AA recovered within 24 months (10 months-4 years) whereas three did not recover within 4-10 years. p-ACTH at time of recovery was higher compared to patients not recovering (P < 0.04). No differences were observed comparing CD and AA patients concerning preoperative 24-h urinary free cortisol (UFC) excretion, postoperative unstimulated s-cortisol or recovery time. By contrast, p-ACTH measured at time of recovery was higher in AA compared to CD (median 12.3 vs. 4.6 pmol/l) (P < 0.001), whereas plasma dehydroepiandrosterone sulfate (p-DHEAS) was lower in AA compared to CD (median 300 vs. 1500 nmol/l) (P = 0.02). CONCLUSION: Recovery of secondary adrenal insufficiency is a slow process in both CD and AA. ACTH measured at time of recovery was significantly higher and DHEAS significantly lower in patients with AA compared to CD, which may suggest different mechanisms of the recovery process and different set points in the glucocorticoid feedback inhibition of ACTH secretion.  相似文献   
47.
Objective Epidemiological data suggest there is an increased risk of dying from heart disease among patients with Klinefelter syndrome (KS). Due to high prevalence of hypogonadism and metabolic syndrome, we speculated that patients with KS may have subclinical changes in the left ventricular function. Therefore, the aim was to assess left ventricular long axis function by tissue Doppler echocardiography in patients with KS and relate these findings to the metabolic status and testosterone levels. Design Cross-sectional study. Out-patient clinic. Patients We investigated 25 unselected patients with KS, recruited from endocrine and fertility clinics. Twenty-five age-matched males served as controls. Measurements Left ventricular systolic long axis function (velocities and strain rate) assessed by tissue Doppler echocardiography related to free testosterone, fasting values of plasma glucose, insulin, homeostasis model assessment (HOMA)-index, cholesterol and triglycerides in addition to dual energy X-ray absorptiometry (DEXA) scan derived assessment of truncal body fat. Results The long axis function was significantly reduced in patients with KS (peak systolic velocities 4·4 ± 1·3 vs. 5·3 ± 1·0 cm/s, P < 0·01 and strain rate –1·3 ± 0·3 vs.–1·6 ± 0·3 s−1, P < 0·01). However, the ventricular dysfunction was mainly attributed KS patients with metabolic syndrome. The peak systolic velocities were significantly correlated to truncal body fat (r = –0·72, P < 0·01) and free testosterone (r = 0·63, P < 0·01), but uncorrelated to plasma glucose, insulin and HOMA-index. Conclusion Systolic long axis function is decreased in patients with KS and metabolic syndrome. The decrease in myocardial systolic function was significantly related to truncal body fat and hypogonadism, but not correlated to insulin sensitivity.  相似文献   
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Background: The Calibrated Automated Thrombography (CAT) is an in vitro thrombin generation (TG) assay that holds promise as a valuable tool within clinical diagnostics. However, the technique has a considerable analytical variation, and we therefore, investigated the analytical and between-subject variation of CAT systematically. Moreover, we assess the application of an internal standard for normalization to diminish variation.

Methods: 20 healthy volunteers donated one blood sample which was subsequently centrifuged, aliquoted and stored at ?80?°C prior to analysis. The analytical variation was determined on eight runs, where plasma from the same seven volunteers was processed in triplicates, and for the between-subject variation, TG analysis was performed on plasma from all 20 volunteers. The trigger reagents used for the TG assays included both PPP reagent containing 5?pM tissue factor (TF) and PPPlow with 1?pM TF. Plasma, drawn from a single donor, was applied to all plates as an internal standard for each TG analysis, which subsequently was used for normalization.

Results: The total analytical variation for TG analysis performed with PPPlow reagent is 3–14% and 9–13% for PPP reagent. This variation can be minimally reduced by using an internal standard but mainly for ETP (endogenous thrombin potential). The between-subject variation is higher when using PPPlow than PPP and this variation is considerable higher than the analytical variation.

Conclusion: TG has a rather high inherent analytical variation but considerable lower than the between-subject variation when using PPPlow as reagent.  相似文献   
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