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101.
PurposeLongitudinal data linking area-level socioeconomic status (SES) to repeated acute coronary syndrome (ACS) events are limited. Using multiple failure-time data, we examined the association between neighborhood SES and ACS in a community-based cohort of myocardial infarction (MI) survivors.MethodsConsecutive patients aged 65 years or younger discharged from eight hospitals in central Israel after first MI in 1992–1993 were followed through 2005. Recurrent MI and unstable angina pectoris (UAP) leading to hospitalization were recorded. Neighborhood SES was assessed through a composite census-derived index developed by the Israel Central Bureau of Statistics. Different variance-corrected proportional hazards models were used to account for multiple recurrent events: Andersen-Gill, Wei-Lin-Weissfeld (WLW), and Prentice-Williams-Peterson.ResultsDuring follow-up, 531 recurrent MIs and 1584 UAP episodes occurred among 1164 patients. Adjusting for known prognostic factors and individual SES using the Andersen-Gill model, higher estimated hazards were associated with poor neighborhood SES (hazard ratio, 1.55; 95% confidence interval [CI], 1.13–2.14 for recurrent MI; and hazard ratio, 1.48; 95% CI, 1.22–1.79 for UAP; in the 5th vs. 95th percentiles). The WLW and Prentice-Williams-Peterson models yielded similar results. When the two outcomes were combined, the WLW-derived hazard ratio was 1.64 (95% CI, 1.39–1.93).ConclusionsMI survivors living in a deprived neighborhood are at higher risk of repeated hospital admissions because of ACS. Secondary prevention initiatives should incorporate multilevel approaches to increase effectiveness and reduce geographic health disparities.  相似文献   
102.
Determining the physical penetration depth of nanoparticles (NPs) into tissues is a challenge that many researchers have been facing in recent years. This paper presents a new noninvasive method for detecting NPs in tissue using an optical iterative technique based on the Gerchberg-Saxton (G-S) algorithm. At the end of this algorithm the reduced scattering coefficient (µs''), of a given substance, can be estimated from the standard deviation (STD) of the retrieved phase of the remitted light. Presented in this paper are the results of a tissue simulation which indicate a linear ratio between the STD and the scattering components. A linear ratio was also observed in the tissue-like phantoms and in ex vivo experiments with and without NPs (Gold nanorods and nano Methylene Blue). The proposed technique is the first step towards determining the physical penetration depth of NPs.OCIS codes: (160.4236) Nanomaterials, (120.5820) Scattering measurements, (190.4710) Optical nonlinearities in organic materials  相似文献   
103.
Zebrafish is emerging as a unique model organism for studying cancer genetics and biology. For several decades zebrafish have been used to study vertebrate development, where they have made important contributions to understanding the specification and differentiation programs in many tissues. Recently, zebrafish studies have led to important insights into thyroid development, and have been used to model endocrine cancer. Zebrafish possess a unique set of attributes that make them amenable to forward and reverse genetic approaches. Zebrafish embryos develop rapidly and can be used to study specific cell lineages or the effects of chemicals on pathways or tissue development. In this review, we highlight the structure and function of endocrine organs in zebrafish and outline the major achievements in modeling cancer. Our goal is to familiarize readers with the zebrafish as a genetic model system and propose opportunities for endocrine cancer research in zebrafish.  相似文献   
104.
The dramatic increase in the prevalence of obesity in women of reproductive age has resulted in approximately 1 in 5 women being obese when they conceive. Bariatric surgery has been shown to be the most effective long-term weight loss strategy in obese women in this age group. Clinicians should be aware of the effects of bariatric surgery on fertility and future pregnancies. Regarding certain complications, pregnancy after bariatric surgery appears to be safer than pregnancy in the obese. In patients where nutrition is properly maintained and monitored, the risks for obesity-related obstetric complications, such as gestational diabetes mellitus and hypertension, are significantly reduced, but possibly at the expense of an increase in neonates born small-for-gestational-age. At the present, definitive conclusions cannot be drawn concerning the risk for Caesarian delivery, differences in type of bariatric procedure, or the optimal surgery-to-conception interval.  相似文献   
105.
Spectroradiometric measurements were taken from eggplant (Solanum melongena) and cauliflower (Brassica oleracea) plants in a controlled experiment treated with sodium chloride (NaCl) concentrations between 30 and 150 mmol. Assessment of seven vegetation indices indicated potential difference between three levels of salinity in effects, with the green indigo ratio (GIR of reflectance of 554 and 436 nm) yielding the most consistent results. Salinity effects started from the second week, but the highest differences were obtained in the fourth week for cauliflower and in the third and sixth weeks for eggplant.  相似文献   
106.
ObjectiveTo evaluate the role of cardiac troponin T (cTnT) in predicting death, recurrent ischemic events, and heart failure among community-dwelling persons with first myocardial infarction (MI).Patients and MethodsConsecutive Olmsted County, Minnesota, residents with an incident MI between November 6, 2002, and December 31, 2007, were studied (N=1177; mean age, 68 years). Maximal cTnT value was measured at a median of 1 day after MI (median, 0.52 ng/mL; interquartile range, 0.16-1.75 ng/mL) and evaluated as a prognostic factor using measures of absolute risk.ResultsDuring a mean follow-up of 16 months, 276 deaths (23%) occurred, 341 patients (29%) experienced a recurrent ischemic event, and 326 patients (28%) experienced heart failure. A dose-response relationship was demonstrated early after MI between cTnT and the adjusted cumulative incidence of all outcomes. The multivariate-adjusted absolute risk differences (events per 100 patients) between the upper and lower cTnT tertiles at 30 days were 5.8 (95% confidence interval [CI], 1.4-10.2) for death, 5.2 (95% CI, 0.2-10.3) for recurrent ischemic event, and 6.9 (95% CI, 1.4-12.4) for heart failure. These differences were either maintained or increased at 2 years.ConclusionIn the community, cTnT level predicts death and nonfatal cardiac events independently of other prognostic factors. The increased risk associated with elevated cTnT level appears shortly after MI and persists for at least 2 years.  相似文献   
107.
A 1926-ins-T mutation in the TrkA gene encoding the tyrosine kinase receptor for nerve growth factor (NGF) was previously documented in patients with congenital insensitivity to pain with anhidrosis (CIPA). These patients suffer from skin lacerations which often evolve into deep tissue infections. Abnormality in neutrophil functions may explain this high rate of severe infections. In this study we show that chemotaxis was significantly (P < 0.001) suppressed in patients' neutrophils, compared to healthy controls. Although NGF alone did not exert a chemotactic effect, its presence enhanced both migration toward fMLP and phosphorylation of MAP kinases (ERK and JNK) in neutrophils from healthy controls, but not in neutrophils from CIPA patients. The significantly impaired chemotactic activity of neutrophils from a CIPA patient, which has been attributed to the molecular defect in the TrkA receptor, may contribute to the high rate of infection.  相似文献   
108.
109.
Objectives  Our aim was to evaluate the relative contribution of maternal weight, GDM severity and glycemic control in women with gestational diabetes (GDM) on the prevalence of LGA infants. Methods  A total of 233 women with GDM were classified according to the fasting and/or postprandial glucose levels as in “good” or “poor” glycemic control. Severity of GDM was categorized using fasting plasma glucose on the 3-h 100 g oral glucose tolerance test (OGTT). Results  The incidence of LGA infants was significantly higher in obese women than in those with lower BMI. There was no significant correlation between GDM severity or level of glycemic control and birth weight or proportion of LGA infants. On multivariate regression analyses, only maternal weight at delivery and fasting glucose level on OGTT were found to be independently and significantly associated with the birth weight, and only maternal weight at delivery was a significant and independent predictor of LGA infants. Conclusions  Both the GDM severity and maternal weight are independent predictors of infants’ birth weights. Maternal weight at delivery is a major risk factor for LGA infants. The study was presented at the SMFM 27th annual meeting on February, 2007.  相似文献   
110.
We evaluated implications of testing for gestational diabetes mellitus (GDM) in pregnancies complicated by third trimester isolated polyhydramnios with previous negative diabetes screening test. In this retrospective cohort study of 104 pregnant women with polyhydramnios between 2005 and 2013, all had normal first trimester fasting glucose and normal glucose challenge test (GCT?p?=?0.38) or fasting glucose values (82 vs. 86?mg/dL, p?=?0.29) between women in the polyhydramnios group with and without late GDM diagnosis. Moreover, no significant difference was found in relation to the mode of delivery or birth weight between the studied groups (3437?±?611 vs. 3331?±?515?g, p?=?0.63). Diagnosis of third trimester polyhydramnios was not associated with increased risk for GDM or neonatal complications.  相似文献   
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