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991.
Hepatic encephalopathy (HE), a consequence of liver damage, is associated with cognitive deficits. In this study, behavioral activity, non-associative learning, associative memory, cognitive coordination and flexibility were investigated in rats with subclinical HE evoked by thioacetamide treatment. Non-associative learning was studied in the open field (OF) set up in 12 HE and 8 saline-injected control rats (C). Memory was examined in spatial place avoidance tasks in 10 HE and 10 C rats. The Room+ Arena- task involved the selection of distal room stimuli from irrelevant arena stimuli (i.e. intramaze cues and/or self-motion information), which engages processes of cognitive coordination. Following the Room+ Arena- training, cognitive flexibility of rats was tested in the Arena+ place avoidance condition, which demands the previously ignored stimuli from arena. In the OF test HE and control rats behaved similar. They displayed high activity in the first block of each session and this pattern was stable. In both groups of rats darkness enhanced locomotor activity in comparison to light only in the first block. The HE and C rats avoided the to-be-avoided place in the Room+ Arena- task, whereas only HE rats were affected in the Arena+ task. In conclusion, these results demonstrate cognitive inflexibility in HE rats. We suggest that (1) the behavioral changes in the TAA model are typical of subclinical HE and (2) test for cognitive flexibility may be modified towards a routine use in patients with subclinical HE.  相似文献   
992.
Persisting motor function deficit after peripheral nerve injury often results from axotomized motoneuron death. Brain-derived neurotrophic factor (BDNF) and its receptor, trkB, are known to promote peripheral nerve regeneration. However, the requirement of BDNF and trkB for adult motoneuron survival after peripheral nerve injury is not established. We studied the number of surviving and regenerating motoneurons after sciatic nerve transection in wild-type and heterozygous trkB-deficient mice. The nerve was either left cut or immediately sewed up or the gap injury model was performed. The gap was provided with an autologous or cross (obtained from other genetic group) graft. Sixteen weeks after surgery, the animals were sacrificed and histological evaluations were performed. In order to study the number of regenerating motoneurons, immunofluorescent tracer was applied to the distal stump of the operated nerve. We found that in wild type mice, the decrease in motoneurons after nerve transection was markedly higher than in trkB-deficient animals, regardless of the operation procedure. Nerve transection resulted in the highest decrease in motoneuron number in wild type mice. This decrease was lower if the nerve was re-joined using a cross-graft obtained from a trkB-deficient animal. Interestingly, in trkB-deficient animals, the decrease in motoneuron count did not depend on type of operation and was similar after nerve transection, re-joining or grafting. The number of regenerating motoneurons after nerve transection and re-joining in wild type animals was lower than in trkB-deficient mice. The number of regenerating motoneurons after nerve grafting did not differ between groups. These results provide further evidence for the role of trkB receptor in spinal motoneuron survival and regeneration.  相似文献   
993.
In this study we present results of investigations of progesterone and estrogen receptors in most frequent, WHO grade I histological types of meningiomas (meningothelial, fibrous, and transitional) and in atypical--WHO grade II variant of these tumors. Samples from 64 tumors were examined. The cohort consisted of 46 WHO grade I (21 transitional, 13 fibrous and 12 meningothelial histologic variants) and of 18 atypical meningiomas. Apart from immunohistochemical examination of progesterone and estrogen receptors, MIB 1 labeling index was estimated. Positive immunoreaction for progesterone receptors was found in 100% meningothelial, 95% transitional, 46% fibrous and 78% atypical variant of meningiomas. Intensity of immunoreaction was stronger in grade I than in grade II tumors. Immunoexpression of estrogen receptors was found in 48% of the investigated meningiomas. No correlation was stated between WHO grade I and grade II tumors, and between meningothelial, transitional and fibrous variants of the neoplasms.  相似文献   
994.
995.
996.
Late ocular manifestations of aneurysmal subarachnoid hemorrhage (SAH) have not been previously investigated except for one study which demonstrated that one half of patients subjected to aneurysm clipping suffer from symptoms of visual pathway impairment. We assessed ophthalmological status of patients after 1–4.5 years from SAH and aneurysm embolization to identify predictors of damage to the visual pathways. Complete ophthalmological examination, static perimetry, and visual evoked potentials (VEPs) were performed in 74 patients (26 men, 48 women, aged 19–76 years), who constituted a consecutive sample of 129 patients treated with aneurysm embolization in the years 2008–2010. The following independent variables: sex, age, time from SAH to embolization, size and site of aneurysm, score in Glasgow Coma Scale, Glasgow Outcome Scale, Hunt-Hess and Fisher scales were subject to univariate and multivariate statistical analyses to study their influence on the ocular outcome. 40 patients (54%) demonstrated visual field defects appearing as multiple peripheral foci and constricted field, affecting both eyes. Among these subjects, 12 patients had severe defects in the visual field, 20 had deterioration in VEPs, and 9 had decreased visual acuity. Older age and high score in Hunt-Hess and Fisher scales were identified as predictors for visual field defects and disturbances in VEPs. More than half of the survivors of SAH and aneurysm embolization suffer from a permanent defect in visual function. Damage of visual pathway correlates with severity of SAH and older age of patients.  相似文献   
997.
998.
Plant sterols are compounds with multiple biological functions, mainly cholesterol-reducing. There are no comprehensive databases on plant sterols, which makes it difficult to estimate their intake in the Polish population. This work attempted to use international food databases, additionally supplemented by scientific data from the literature, to create a database of plant sterols, which would cover various kinds of foods and dishes consumed in Poland. The aim was to assess the size and sources of dietary plant sterols in the adult population of Poland. The literature search was conducted using PubMed, Web of Science, Scopus, and Google Scholar to identify possible sources of published food composition data for plant sterols. The study group consisted of 5690 participants of the WOBASZ II survey. We identified 361 dietary sources of plant sterols based on the consumption of foods and dishes reported by participants. Cereals and fats provided 61% of the total plant sterols, and together with vegetables and fruits, this totaled 80%. The median intake of plant sterols in the Polish population was 255.96 mg/day, and for men and women 291.76 and 230.61 mg/day, respectively. Canola oil provided the most plant sterols at 16.92%, followed by white bread at 16.65% and soft margarine at 8.33%. The study found that plant sterol intake in Poland is comparable to other populations, and women’s diets are more dense in plant sterols. Due to the lack of literature sources on plant sterol content in some foods, future studies should expand and complete the databases on plant sterol content in foods.  相似文献   
999.
The paper presents the designs and methods of a cross-sectional study of two groups of randomly selected Polish inhabitants aged 19–64, and 65 and over, carried out as part of the National Health Program. The aim of the study was to illustrate the current health situation of the respondents in terms of nutrition and physical activity level. The quantitative and qualitative methods were used. The Computer Assisted Personal Interview technique was used. The dietary research was carried out through repeated interviews about the frequency of food consumption, and about what food had been consumed in the previous 24 h. In addition to the questionnaire studies, anthropometric data, blood pressure and the level of physical activity were measured. During the COVID-19 pandemic, some methods were modified according to hygiene rules. The Computer Assisted Telephone Interview technique was used to collect the data, and the anthropometric data were obtained via measurements made by the respondents themselves based on detailed instructions. The results will be used to present representative data for the Polish population, describing a wide range of eating behaviours and other lifestyle elements, food and nutrition knowledge, dietary supplement use, the occurrence of diet-related diseases, nutritional status and, in the seniors group, the risk of sarcopenia.  相似文献   
1000.
Introduction: Nowadays, the final success of implantation is not only based on obtaining osseointegration of the implant but is also determined by achieving a satisfactory aesthetic effect of the soft tissues surrounding the implant, which can be defined as an aesthetic integration. The process of obtaining this aesthetic integration already begins at the stage of placing the healing abutment, which allows us to obtain the emergence profile necessary for our prosthetic reconstruction. Materials and Methods: The study used cone-beam computer tomography (CBCT) scans of 51 patients. The measurements of the maxillary teeth (central incisor, lateral incisor, canine, first premolar, and first molar) were performed from cross-sections of the individual teeth at the transition zone to design a custom anatomic healing abutment milled from zirconium and luted to the non-index Ti-base. Results: The obtained results allowed to design and create the shape of the anatomic healing abutment. Conclusions: The use of laboratory-produced anatomical healing abutments is possible and may allow to obtain the desired and planned emergence profiles of prosthetic restorations. In addition, it might be a method of reducing work time at the dental chair but further clinical trials are necessary.  相似文献   
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