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21.
Respiratory morbidity in Inuit children is high. However, little is know regarding lung function measures in this population. The forced expiratory volumes in one second (FEV(1)) and forced vital capacity (FVC) in 888 Greenlandic Inuits (N=888) and Danes (N=477) aged 6-18 years were compared. Furthermore, associations between level of lung function and atopy and lifestyle factors were estimated in Greenlanders. The effect of height on FEV(1) and FVC was significantly different in Greenlanders and Danes, this difference in lung function increased with increasing height, and could not be explained by differences in age weight and BMI. Thus, Greenlanders taller than 130 cm had up to 300-400 ml higher FEV(1) and FVC compared with Danes of the same height. Among Greenlanders, those living in settlements had the highest levels of both FEV(1) and FVC. Greenlanders had elevated levels of FEV(1) and FVC compared with Danes. The Inuit having a shorter limb length in relation to trunk height may account for these differences. However, our finding that Greenlanders living in settlements had the highest lung function level also suggests a possible role of factors in the traditional Greenlandic lifestyle.  相似文献   
22.
Previous studies have suggested that transmission of measles virus from the opposite sex increases the severity of infection; however, the role of gender in the transmission of other infections has not been examined. Multiple polio cases within a family usually occur simultaneously, and are therefore likely to be secondary to a common subclinical index case. The few clinical polio cases that appear much later than any other clinical case are likely to be tertiary cases. If cross-sex transmission increases the severity of infection then multiple polio cases would tend to affect the same sex, i.e. the opposite sex to that of the subclinical index case. In order to assess this phenomenon we identified 6345 records of individuals hospitalized with poliomyelitis in Copenhagen between 1919 and 1953. The severity and gender of suspected secondary and tertiary cases were analysed among all multiple household cases. Overall, 70% of the 133 sibling pairs having polio simultaneously were same-sex pairs, which differed significantly from the expected 52% (chi2 = 9.1; p < 0.01). Tertiary cases with exposure to the opposite sex were more likely to be paralytic than cases with exposure to the same sex [relative risk (RR) = 2.86 (95% confidence interval 1.08-7.58)1. In families with adult polio cases, possible tertiary cases were more common among fathers (7/24) than among mothers (1/35) [RR = 10.21 (1.34-77.72)]. We examined whether the excess of male polio cases was more pronounced in small families where the mother would play a relatively larger role in disease transmission and found that the male:female excess decreased with increasing birth order (p = 0.02) and family size (p = 0.09). The strong tendency towards same-sex pairs in 2-case families suggests that gender plays an important role in the severity of polio infection. Cross-sex transmission may increase the severity of polio and mothers may contribute to the higher prevalence of polio cases among boys.  相似文献   
23.
Programmable cells: interfacing natural and engineered gene networks   总被引:10,自引:0,他引:10       下载免费PDF全文
Novel cellular behaviors and characteristics can be obtained by coupling engineered gene networks to the cell's natural regulatory circuitry through appropriately designed input and output interfaces. Here, we demonstrate how an engineered genetic circuit can be used to construct cells that respond to biological signals in a predetermined and programmable fashion. We employ a modular design strategy to create Escherichia coli strains where a genetic toggle switch is interfaced with: (i) the SOS signaling pathway responding to DNA damage, and (ii) a transgenic quorum sensing signaling pathway from Vibrio fischeri. The genetic toggle switch endows these strains with binary response dynamics and an epigenetic inheritance that supports a persistent phenotypic alteration in response to transient signals. These features are exploited to engineer cells that form biofilms in response to DNA-damaging agents and cells that activate protein synthesis when the cell population reaches a critical density. Our work represents a step toward the development of "plug-and-play" genetic circuitry that can be used to create cells with programmable behaviors.  相似文献   
24.
Metabolic Brain Disease - Hepatic encephalopathy (HE) is cerebral dysfunction caused by liver failure and inflicts 30-40% of patients with liver cirrhosis during their disease course. Clinically...  相似文献   
25.
We report two cases of transient significantly elevated plasma cobalamin (B12) in geriatric patients acutely admitted with fever, increased C-reactive protein and X-ray verified pneumonia. Extensive diagnostic workup did not reveal kidney or liver disease, neither any signs of cancer. Furthermore, none of the patients had received therapeutic B12 supplementation prior to admission. In both cases, plasma B12 normalized at an out-patient control few months later. We were not able to identify the reason for the initial B12 elevation in any of the patients, since none of the usually recognized causes were evident. Since both patients had an infection and temporarily elevated B12, we suggest a possible inflammatory response or a vitamin B12 production by the infectious agents as the cause. Both suggestions, however, need further exploration.  相似文献   
26.
Journal of Interventional Cardiac Electrophysiology - To evaluate the association between different right ventricular (RV) lead positions as assessed by cardiac computed tomography (CT) and...  相似文献   
27.
28.
The renin–angiotensin system is essential for body fluid homeostasis and blood pressure regulation. This review focuses on the homeostatic regulation of the secretion of active renin in the kidney, primarily in humans. Under physiological conditions, renin secretion is determined mainly by sodium intake, but the specific pathways involved and the relations between them are not well defined. In animals, renin secretion is a log-linear function of sodium intake. Close associations exist between sodium intake, total body sodium, extracellular fluid volume, and blood volume. Plasma volume increases by about 1.5 mL/mmol increase in daily sodium intake. Several lines of evidence indicate that central blood volume may vary substantially without measurable changes in arterial blood pressure. At least five intertwining feedback loops of renin regulation are identifiable based on controlled variables (blood volume, arterial blood pressure), efferent pathways to the kidney (nervous, humoral), and pathways operating via the macula densa. Taken together, the available evidence favors the notion that under physiological conditions (1) volume-mediated regulation of renin secretion is the primary regulator, (2) macula densa mediated mechanisms play a substantial role as co-mediator although the controlled variables are not well defined so far, and (3) regulation via arterial blood pressure is the exception rather than the rule. Improved quantitative analyses based on in vivo and in silico models are warranted.  相似文献   
29.
Employing cyto‐, myelo‐, and chemoarchitectural staining techniques, we analyzed the structure of the hippocampal formation in the banded mongoose and domestic ferret, species belonging to the two carnivoran superfamilies, which have had independent evolutionary trajectories for the past 55 million years. Our observations indicate that, despite the time since sharing a last common ancestor, these species show extensive similarities. The four major portions of the hippocampal formation (cornu Ammonis, dentate gyrus, subicular complex, and entorhinal cortex) were readily observed, contained the same internal subdivisions, and maintained the topological relationships of these subdivisions that could be considered typically mammalian. In addition, adult hippocampal neurogenesis was observed in both species, occurring at a rate similar to that observed in other mammals. Despite the overall similarities, several differences to each other, and to other mammalian species, were observed. We could not find evidence for the presence of the CA2 and CA4 fields of the cornu Ammonis region. In the banded mongoose the dentate gyrus appears to be comprised of up to seven lamina, through the sublamination of the molecular and granule cell layers, which is not observed in the domestic ferret. In addition, numerous subtle variations in chemoarchitecture between the two species were observed. These differences may contribute to an overall variation in the functionality of the hippocampal formation between the species, and in comparison to other mammalian species. These similarities and variations are important to understanding to what extent phylogenetic affinities and constraints affect potential adaptive evolutionary plasticity of the hippocampal formation.  相似文献   
30.
There is limited information about the in-hospital plasma profile of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in patients with non-ST-elevation acute coronary syndrome (NSTACS) and furthermore, the prognostic influence of the timing of NT-proBNP measurements in NSTACS is unsettled. These subject matters are elucidated in this study composed of 455 patients with NSTACS (symptoms <24 h). NT-proBNP was measured at 0, 6, 12, 24, 36, 48, 72 and 96 h following admission. Any death was registered at follow-up (median: 2.3 years). The study demonstrated a monophasic profile of the plasma NT-proBNP values, reaching a maximum at 6 hours, and it showed an independent prognostic significance of NT-proBNP irrespective of the sampling time. Risk prediction by NT-proBNP was improved by combining the baseline measurement and one value taken between 24 and 96 h (at 48 h, P<0.001). No additional prognostic information was provided by including more than one late in-hospital NT-proBNP value. Conclusions: The in-hospital NT-proBNP measurements exhibit a monophasic profile in patients with NSTACS and these values provide independent prognostic information as regards mortality irrespective of the sampling time. Moreover, risk prediction of NT-proBNP is strengthened by combining the admission measurement with an additional value during the hospitalization.  相似文献   
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