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101.
The nature, neural underpinnings, and etiology of deficits in verbal declarative memory in patients with schizophrenia remain unclear. To examine the contributions of genes and environment to verbal recall and recognition performance in this disorder, the California Verbal Learning Test was administered to a large population-based Finnish twin sample, which included schizophrenic and schizoaffective patients, their non-ill monozygotic (MZ) and dizygotic (DZ) co-twins, and healthy control twins. Compared with controls, patients and their co-twins showed relatively greater performance deficits on free recall compared with recognition. Intra-pair differences between patients and their non-ill co-twins in hippocampal volume and memory performance were highly positively correlated. These findings are consistent with the view that genetic influences are associated with reduced verbal recall in schizophrenia, but that non-genetic influences further compromise these abnormalities in patients who manifest the full-blown schizophrenia phenotype, with this additional degree of disease-related declarative memory deficit mediated in part by hippocampal pathology.  相似文献   
102.
103.
Driving ability of three patients having a right hemisphere infarct and residual visual inattention was examined. The neuropsychological examination included the Peripheral Perception Test and the Signal Detection Test from the Vienna Test System, and the Behavioural Inattention Test (BIT). Driving ability was assessed with an on-road evaluation. The patients had no neglect based on the BIT and had normal visual fields, but they showed slightly poorer visual search on the left side. All patients passed the official on-road driving test and were considered capable of driving. This study raises the question if acute neglect can recover to a degree in which driving may be possible.  相似文献   
104.
Following our search for antimalarial compounds, novel series of ferrocenyl-substituted pyrrolo[1,2-a]quinoxalines 1-2 were synthesized from ferrocene-carboxaldehyde and tested for their in vitro activity upon the erythrocytic development of Plasmodium falciparum strains with different chloroquine-resistance status. The ferrocenic pyrrolo[1,2-a]quinoxalines 1-2 were prepared in 6 or 9 steps through a Barton-Zard reaction. Promising pharmacological results against FcB1, K1 and F32 strains were obtained with ferrocenyl pyrrolo[1,2-a]quinoxalines 1j-l linked by a bis-(3-aminopropyl)piperazine linker substituted by a nitrobenzyl moiety.  相似文献   
105.
Hereditary gelsolin amyloidosis (HGA) is a dominantly inherited systemic disease reported worldwide. HGA is characterized by ophthalmological, neurological, and dermatological manifestations. AGel amyloid accumulates at basal lamina of epithelial and muscle cells, thus amyloid angiopathy is encountered in nearly every organ. HGA patients have cardiovascular, hemorrhagic, and potentially vascularly induced neurological problems. To clarify pathomechanisms of AGel angiopathy, we performed histological, immunohistochemical, and electron microscopic analyses on facial temporal artery branches from 8 HGA patients and 13 control subjects. We demonstrate major pathological changes in arteries: disruption of the tunica media, disorganization of vascular smooth muscle cells, and accumulation of AGel fibrils in arterial walls, where they associate with the lamina elastica interna, which becomes fragmented and diminished. We also provide evidence of abnormal accumulation and localization of collagen types I and III and an increase of collagen type I degradation product in the tunica media. Vascular smooth muscle cells appear to be morphologically and semi‐quantitatively normal, only their basal lamina is often thickened. In conclusion, angiopathy in HGA results in severe disruption of arterial walls, characterized by prominent AGel deposition, collagen derangement and severe elastolysis, and it may be responsible for several, particularly hemorrhagic, disease manifestations in HGA.  相似文献   
106.
AIMS: The aim of the present study is to understand the changes in left ventricular (LV) regional systolic deformation based on strain rate (SR) imaging in patients with isolated mitral regurgitation (MR). Progressive LV dilatation and irreversible myocardial damage as a result of chronic isolated MR are important causes of morbidity and mortality in patients following valve surgery. To date, there is no specific diagnostic method to detect subclinical changes in systolic function before irreversible dysfunction occurs. METHODS AND RESULTS: Seventy-seven individuals were studied: 54 asymptomatic patients (age 56 +/- 12) with isolated non-ischaemic MR divided into three groups: mild, moderate, and severe and 23 healthy subjects. All underwent a standard echo examination and a tissue Doppler study. A mathematical study was carried out to predict how SR should alter with increasing dimensions and due to irreversible myocardial damage. Radial as well as longitudinal peak systolic SR was significantly decreased in patients with severe MR compared to the other groups (LV posterior wall: P = 0.0006, septum: P = 0.0004, LV lateral wall: P = 0.0003). From both modelling and in our patients, deformation correlated inversely with LV end-diastolic diameter and end-systolic diameter (ESD). Deformation measurements (corrected for increased geometry) enabled the identification of patients classically referred to as at risk of irreversible myocardial damage (ESD > or = 4.5 cm). CONCLUSION: In patients with a wide range of MR, deformation remains unchanged due to a balance of increased dimensions and increased stroke volume. Only when contractility is expected to change, deformation will significantly decrease. SR imaging indices, corrected for geometry, might potentially be useful in detecting subclinical deterioration in LV function in asymptomatic patients with severe MR.  相似文献   
107.
Bacteria are known to communicate with each other and regulate their activities in social networks by secreting and sensing signaling molecules called autoinducers, a process known as quorum sensing (QS). This is a growing area of research in which we are expanding our understanding of how bacteria collectively modify their behavior but are also involved in the crosstalk between the host and gut microbiome. This is particularly relevant in the case of pathologies associated with dysbiosis or disorders of the intestinal ecosystem. This review will examine the different QS systems and the evidence for their presence in the intestinal ecosystem. We will also provide clues on the role of QS molecules that may exert, directly or indirectly through their bacterial gossip, an influence on intestinal epithelial barrier function, intestinal inflammation, and intestinal carcinogenesis. This review aims to provide evidence on the role of QS molecules in gut physiology and the potential shared by this new player. Better understanding the impact of intestinal bacterial social networks and ultimately developing new therapeutic strategies to control intestinal disorders remains a challenge that needs to be addressed in the future.  相似文献   
108.

Background

Inverted T waves in the electrocardiogram (ECG) have been associated with coronary heart disease (CHD) and mortality. The pathophysiology and prognostic significance of T-wave inversion may differ between different anatomical lead groups, but scientific data related to this issue is scarce.

Methods

A representative sample of Finnish subjects (n = 6,354) aged over 30 years underwent a health examination including a 12-lead ECG in the Health 2000 survey. ECGs with T-wave inversions were divided into three anatomical lead groups (anterior, lateral, and inferior) and were compared to ECGs with no pathological T-wave inversions in multivariable-adjusted Fine–Gray and Cox regression hazard models using CHD and mortality as endpoints.

Results

The follow-up for both CHD and mortality lasted approximately fifteen years (median value with interquartile ranges between 14.9 and 15.3). In multivariate-adjusted models, anterior and lateral (but not inferior) T-wave inversions associated with increased risk of CHD (HR: 2.37 [95% confidence interval 1.20–4.68] and 1.65 [1.27–2.15], respectively). In multivariable analyses, only lateral T-wave inversions associated with increased risk of mortality in the entire study population (HR 1.51 [1.26–1.81]) as well as among individuals with no CHD at baseline (HR 1.59 [1.29–1.96]).

Conclusions

The prognostic information of inverted T waves differs between anatomical lead groups. T-wave inversion in the anterior and lateral lead groups is independently associated with the risk of CHD, and lateral T-wave inversion is also associated with increased risk of mortality. Inverted T wave in the inferior lead group proved to be a benign phenomenon.
  相似文献   
109.

Objective

To examine the relationship between maternal intelligence-mental health and neuropsychological development at age 14 months in a normal population, taking into account maternal occupational social class and education.

Methods

We prospectively studied a population-based birth cohort, which forms part of the INMA (Environment and Childhood) Project. Cognitive and psychomotor development was assessed at 14 months using Bayley Scales of Infant Development. Maternal intelligence and mental health were assessed by the Cattell and Cattell test and the General Health Questionnaire-12 respectively.

Results

We observed a crude association between maternal intelligence and cognitive development in children at 14 months but this association disappeared when maternal education was included. The associations were stratified by maternal education and occupational social class. Within the manual maternal occupational social class, there was a significant difference in cognitive development between children whose mothers scored in the highest tertile of maternal IQ and those whose mothers scored in the lowest tertile. In contrast, no differences were observed among children whose mothers were in the non-manual occupational social class.

Conclusions

The association between maternal intelligence and child cognitive development differed by occupational social class. While this association was not confounded by education or other variables in manual occupational social classes, maternal education explained this association among advantaged occupational social classes.  相似文献   
110.

Objectives

Shortly after pertussis vaccination was reintroduced in Sweden in 1996, an intensified pertussis disease surveillance programme was set up. In this study, we report on in-depth analyses of age–dose–number-specific incidences and the rate of pertussis hospitalisation for children with no, 1 or 2 doses of an acellular pertussis vaccine before pertussis disease. Vaccine coverage, the timeliness of childhood vaccination and the effect of later than scheduled pertussis vaccination(s) are also examined.

Study design

Children with notified laboratory-confirmed (culture or PCR) pertussis disease were evaluated among the surveillance population of about 1 million infants, born between 1996 and 2007 and followed for pertussis disease from October 1997 to December 2007, for nearly 6 million person-years. Birth and vaccination dates of the diseased children are known from the surveillance programme. To estimate denominators of the age–dose–number-specific pertussis incidences, we used birth and vaccination dates from a vaccine trial with more than 72,000 infants combined with national pertussis vaccine coverage data for children in the surveillance population.

Results

For infants from 3 to <5 months of age, the incidence of pertussis disease with at least 14 days of cough decreased from 264/100,000 for unvaccinated infants to 155/100,000 for infants with one dose of a pertussis vaccine prior to onset of the disease. In the age range 5 to <12 months, the age–dose specific incidences were 526, 95, and 24/100,000 for infants with no, 1 and 2 doses, respectively. The rate of hospitalisation for infants with 1 dose of a pertussis vaccine prior to onset of the disease was significantly lower than for unvaccinated infants of the same age.For many infants, there is a delay in administration of the vaccine doses according to the regular 3–5–12 month schedule (which has been the case for many years). Hypothetically, if all infants had been vaccinated exactly on schedule, we would expect about 28% fewer pertussis cases with at least 14 days of cough and 38% fewer hospitalisations due to pertussis, of cases possible to influence by vaccinations on schedule.

Conclusion

Pertussis vaccination had a significant effect among infants already after the first dose. This is particularly important for premature infants and infants with severe respiratory and cardiac diseases. A moderate decrease in the incidence of pertussis disease in infants and rate of hospitalisation could be expected if primary vaccinations were carried out closer to the scheduled time than is currently the practice in Sweden.  相似文献   
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