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91.
The associations between 5-HTT-linked polymorphic region (5-HTT-LPR), monoamine oxidase A (MAOA)-LPR and the dimensions of temperament evaluated using the Temperament and Character Inventory (TCI) and NEO Five-Factor Inventory (NEO-FFI) were studied. One hundred healthy volunteers (without psychiatric disorders) were recruited to represent a cross-section of the population of Szczecin (Poland) in terms of sex, age and education. No associations between 5-HTT-LPR and the TCI harm avoidance dimension and between 5-HTT-LPR and the NEO-FFI neuroticism dimension were found. Males carrying the 3-VNTR MAOA gene variant (209 bp) had significantly lower values on the NEO-FFI openness dimension (p = 0.039) and obtained higher scores on the subdimension 3 of the TCI reward dependence (RD3), i.e. attachment vs. detachment (p = 0.005). Individuals carrying the 'short' variant of 5-HTT-LPR had lower values on the reward dependence dimension and the RD4 subdimension (dependence vs. independence) than individuals not carrying the 'short' variant (p = 0.039 and p = 0.011, respectively). Females carrying the 'short' variant had lower values on NS1 (exploratory excitability vs. stoic rigidity) and RD4 (dependence vs. independence) than those not carrying the variant (p = 0.042 and 0.043, respectively). The obtained level of significance with respect to the observed associations between 5-HTT-LPR and the reward dependence scales and subscales and between 5-HTT-LPR and the NS1 subscale are too weak for further interpretation. Our results do not confirm the hypothesis that there is a simple correlation between single gene polymorphisms and a personality trait measured by the TCI and NEO-FFI scales.  相似文献   
92.
Recent data, especially from immunocompromised patients, suggest that human cytomegalovirus (HCMV) plays an important role in lung pathology. In this study the serological status of HCMV infection and characteristic of the HCMV infected patients with interstitial lung diseases were determined. The subjects were enrolled prior to immunosuppression therapy introduction.  相似文献   
93.
Summary Determinations of enzymatic activity, protein structure and phospholipid composition of sarcoplasmic reticulum isolated from the soleus muscle (S), extensor digitorum longus muscle (EDL) and gastrocnemius muscle (G)) in rats were carried out after various periods of 20,25-diazacholesterol administration. The sarcoplasmic reticulum from G and EDL of myotonic rats exhibited a rise in basal ATP-ase activity and a fall of total phospholipids. The protein of molecular weight of 100000 daltons in G and EDL was slightly more pronounced.The investigations were carried out as a part of agreement with NIH, Bethesda, USA, No. 05-002-1.  相似文献   
94.
BACKGROUND: Cardiovascular diseases are the main causes of morbidity and mortality in kidney transplant recipients. Blood viscosity plays an important role in the development of arteriosclerosis in the general population. Since hematocrit (Ht) and hemoglobin (Hb) values are determinants of blood viscosity, we decided to perform a study to check the possible relevance between these hemorheological factors and carotid intima-media thickness (IMT) in renal transplant recipients. PATIENTS AND METHODS: The study was performed on 33 clinically stable renal transplant recipients and 19 healthy persons. All subjects underwent ultrasonographic measurements of IMT. Analyzed clinical parameters included: age, sex, body mass index (BMI), mean arterial blood pressure (MAP), pulse pressure (PP) time from renal transplantation, and time on dialysis. The following biochemical parameters were assessed: Hb, Ht, fibrinogen (Fbg), and homocysteine (tHcy) concentrations (estimated by enzyme immunoassay). RESULTS: The two analyzed groups did not differ in respect to age and BMI. Mean concentrations of Hb and Ht values were lower in the patients group. Mean carotid IMT, Fbg, tHcy, MAP, and PP were significantly higher in the renal transplant recipients group when compared to the control group. IMT was positively correlated with age (r=0.55; p=0.001), Hb (r=0.36; p=0.04), Ht (r=0.34; p<0.05), PP (r=0.35; p<0.05), Fbg (r=0.4; p=0.02), and time on dialysis prior to transplantation (r=0.50; p=0.003) in the patients group. Multiple regression analysis in renal transplant recipients showed that the IMT was independently related to age, Hb or Ht values, and Fbg. CONCLUSIONS: The results for the first time show positive association between IMT and Ht and Hb values in renal transplant recipients. The results may implicate the role of these rheological factors in progression and acceleration of arterial remodeling in renal transplant recipients.  相似文献   
95.

Differences in size between males and females, called the sexual size dimorphism, are common in insects. These differences may be followed by differences in the duration of development. Accordingly, it is believed that insect sex may be used to increase the accuracy of insect age estimates in forensic entomology. Here, the sex-specific differences in the development of Creophilus maxillosus were studied at seven constant temperatures. We have also created separate developmental models for males and females of C. maxillosus and tested them in a validation study to answer a question whether sex-specific developmental models improve the accuracy of insect age estimates. Results demonstrate that males of C. maxillosus developed significantly longer than females. The sex-specific and general models for the total immature development had the same optimal temperature range and similar developmental threshold but different thermal constant K, which was the largest in the case of the male-specific model and the smallest in the case of the female-specific model. Despite these differences, validation study revealed just minimal and statistically insignificant differences in the accuracy of age estimates using sex-specific and general thermal summation models. This finding indicates that in spite of statistically significant differences in the duration of immature development between females and males of C. maxillosus, there is no increase in the accuracy of insect age estimates while using the sex-specific thermal summation models compared to the general model. Accordingly, this study does not support the use of sex-specific developmental data for the estimation of insect age in forensic entomology.

  相似文献   
96.
The study investigated the effectiveness of the combination of chemical and physical methods of natural fibers’ modification. The long flax fibers were subjected to various types of modification. These were silanization, plasma modification and a combination of these methods. For the silanization process, two types of silanes were used: amino- and vinylsilane. The application of structurally different compounds allowed us to acquire knowledge about the effect of the modifier structure on its properties. Various properties of flax fibers were investigated, comparing the results before and after different modification processes. The flammability of prepared samples were tested by pyrolysis combustion flow calorimeter (PCFC). In the effect of the natural fibers’ modifications, flammability was reduced even by 30%. The thermal stability of modified fibers increased. The FTIR tests of the gases released during thermal degradation of the tested fibers allowed us to determine the important compounds and prove a lower degree of flax-fiber decomposition after modification. Flax fibers were also tested to evaluate their physical properties (linear mass, average diameter, aspect ratio and hygroscopicity). Changes in surface morphology were observed by scanning electron microscope (SEM). The properties of natural fibers improved significantly, thus contributing to an increase in their suitability for the use in composites.  相似文献   
97.
Objectives:In this study, we aimed to assess the impact of different CT reconstruction kernels on the stability of radiomic features and the transferability between different diseases and tissue types. Three lung diseases were evaluated, i.e. non-small cell lung cancer (NSCLC), malignant pleural mesothelioma (MPM) and interstitial lung disease related to systemic sclerosis (SSc-ILD) as well as four different tissue types, i.e. primary tumor, largest involved lymph node ipsilateral and contralateral lung.Methods:Pre-treatment non-contrast enhanced CT scans from 23 NSCLC, 10 MPM and 12 SSc-ILD patients were collected retrospectively. For each patient, CT scans were reconstructed using smooth and sharp kernel in filtered back projection. The regions of interest (ROIs) were contoured on the smooth kernel-based CT and transferred to the sharp kernel-based CT. The voxels were resized to the largest voxel dimension of each cohort. In total, 1386 features were analyzed. Feature stability was assessed using the intraclass correlation coefficient. Features above the stability threshold >0.9 were considered stable.Results:We observed a strong impact of the reconstruction method on stability of the features (at maximum 26% of the 1386 features were stable). Intensity features were the most stable followed by texture and wavelet features. The wavelet features showed a positive correlation between percentage of stable features and size of the ROI (R2 = 0.79, p = 0.005). Lymph node radiomics showed poorest stability (<10%) and lung radiomics the largest stability (26%). Robustness analysis done on the contralateral lung could to a large extent be transferred to the ipsilateral lung, and the overlap of stable lung features between different lung diseases was more than 50%. However, results of robustness studies cannot be transferred between tissue types, which was investigated in NSCLC and MPM patients; the overlap of stable features for lymph node and lung, as well as for primary tumor and lymph node was very small in both disease types.Conclusion:The robustness of radiomic features is strongly affected by different reconstruction kernels. The effect is largely influenced by the tissue type and less by the disease type.Advances in knowledge:The study presents to our knowledge the most complete analysis on the impact of convolution kernel on the robustness of CT-based radiomics for four relevant tissue types in three different lung diseases.   相似文献   
98.

Introduction

Malnutrition is a negative predictive factor for survival in end stage renal disease (ESRD) patients. Coincidence of malnutrition, inflammation and atherosclerosis (MIA syndrome) in the dialysis population is an exceptionally poor outcome event. Due to flexibility, ease of performance and reproducibility, clinical scales are of particular value in assessment of nutritional status in ESRD patients. The aim of the present study was to evaluate the clinical value of Mini Nutritional Assessment (MNA) in peritoneal dialysis (PD) patients.

Material and methods

Nutritional status was assessed in 41 peritoneal dialysis patients by means of the MNA scale and malnutrition inflammation score (MIS). Some other clinical and laboratory parameters associated with nutritional status were analyzed. Patients were followed up for 30 months.

Results

In the analyzed group of patients a good nutritional state was diagnosed in 22 patients (54%), risk of malnutrition in 17 (41%) and malnutrition in 2 patients (5%) based on the MNA scale. A strong correlation between MNA based nutritional status and MIS was found (r = –0.85, p < 0.01, ANOVA, p < 0.01). Differences in time on dialysis, body mass index, concentration of albumin, cholesterol and triglycerides were noted between at risk/malnourished and well-nourished (according to MNA) patients. Statistically significant factors determining survival of patients by Cox proportional hazard analysis were age (HR 1.07), being at risk/malnourished according to MNA (HR 5.7), MIS (HR 1.2), and albumin (HR 0.13).

Conclusions

The MNA scale is a valuable, clinically suitable tool for assessment of nutritional status in peritoneal dialysis patients. Risk of malnutrition and malnutrition diagnosed by MNA identifies patients at high mortality risk.  相似文献   
99.

Background

India is a country with vast unmet medical needs. eHealth has the potential to improve the quality of health care and reach the unreached. We have sought to understand the kinds of eHealth programmes being offered in India today, the challenges they face and the nature of their financing.

Methods

We have adopted an interview-based methodology. The 30 interviews represent 28 organizations, and include designers, implementers, evaluators and technology providers for eHealth programmes.

Results

A range of programmes is being run, including point-of-care in rural and urban areas, treatment compliance, data collection and disease surveillance, and distant medical education. Most programmes provide point-of-care to patients or other beneficiaries in rural areas. Technology is not a limiting factor but the unavailability of suitable health personnel is a major challenge, especially in rural areas. We have identified a few factors that help this situation. Financial sustainability is also a concern for most programmes, which have rarely been scaled up. There are recent for-profit efforts in urban areas, but no reliable business model has been identified yet. Government facilities have not been very effective in eHealth on their own, but collaborations between the government and non-profit (in particular) and for-profit organisations have led to impactful programmes.

Conclusions

It is unlikely that eHealth will have widespread and sustainable impact without government involvement, especially in rural areas. Nevertheless, programmes run solely by the government are unlikely to be the most effective.  相似文献   
100.

Background

Expandable cervical cages have been utilised successfully to reconstruct the cervical spine for various conditions. However, to date there are only limited data on their influence on cervical sagittal profile. In this retrospective study, we present our experience with performing anterior cervical corpectomy in one or two levels using expandable titanium cages in order to achieve stable reconstruction and restoration of cervical lordosis.

Methods

A case series of data from 48 consecutive patients (20 men, 28 women; mean age 61 years) operated upon in a 5-year-period is retrospectively reviewed. Standard anterior single- or two-level cervical corpectomy, fusion and spinal reconstruction were performed, including placement of an expandable titanium cage and an anterior cervical plate. The mean follow-up was 23 months (range, 8–42 months). Outcome was measured by clinical examinations and visual analogue scale (VAS) scale; myelopathy was classified according the Nurick grading system. Radiographic analysis comprised several parameters, including segmental Cobb angle, cervical lordosis, subsidence ratio and sagittal cage angle. Computed tomography was done 1 and 2 years after surgery; cervical spine radiographs were obtained 3, 6, 12 and 24 months after surgery.

Results

In 38 patients (79 %) osseous fusion or stability of construct could be demonstrated in the 2-year follow up examination. The mean restoration of segmental Cobb angle as well as cervical lordosis amounted to 7.6° and 5.4° respectively, both being statistically significant. Furthermore, a profound correction (10° or more) of the sagittal cervical curve was shown in 15 patients.

Conclusion

Regarding the restoration of the physiological sagittal cervical profile, expandable cervical cages seem to be efficient and easy to use for cervical spine reconstruction after anterior corpectomy. Donor-site-related complications are avoided, fast and strong reconstruction of the anterior column is provided, resulting in satisfactory fusion rates after 2 years.  相似文献   
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