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111.
The twin-reversed arterial perfusion (TRAP) sequence and development of an acardius are rare and severe complications in monozygotic twin pregnancy. Haemodynamic disturbances in placental perfusion via abnormal vascular anastomoses allow inter-twin transfusion to occur. Because of blood perfusion, one of the twins is poorly oxygenated and contains metabolic waste products. Retrograde placental perfusion leads to the formation of a non-viable malformed acardiac foetus. We studied the effects of haemodynamic disturbances in acardiac foetus on the development of the nervous system. The acardius was a product of a 32-weeks pregnancy. Caesarean section yielded a skin covered ovoid mass (size, 10 x 8 cm; weight, 220 g). The dissection of the acardiac twin showed a skin with hair and appendages, rudimentary lower limbs, vertebral column and brain mass. The rudimentary brain tissue was considerably disorganised structurally. We distinguished two main morphological forms of various appearances. In the centre, we observed a scarcely vascularised mass of tissue containing mature and immature neurones, glial cells and randomly distributed fibres. The mass of tissue appeared poorly differentiated, although there were some arrangements reminiscent of cerebral structures. Clusters of neurones provided a slight suggestion of nuclear or fibre structure. The cerebellar cortex was the only well recognisable structure. In the other fragment of the tissue, we found a slit cavity with ependymal outline and well-developed choroid plexus, which seemed to represent the 3rd ventricle. The scarcely vascularised disorganised tissue was surrounded by the highly vascularised one. It included many thin-walled sinusoid vessels. In some places, they were so concentrated that they resembled cavernous haemangioma. The spinal cord appeared comparatively well organised with a slightly dilated central canal. The morphological picture of the rudimentary brain tissue was similar to the picture of the cerebrovasculosa area. The effect of ischaemia in the presented case is the anomalous formation of the cerebral structures. The morphological features imply that the failure occurred after neurulation and before the prosencephalic began to grow. The failure of neural tube formation occurred on the 22nd-25th day of gestation. The malformed formation of the nervous system might be caused by impaired induction due to altered gene expression or to the interference of exogenous agents that interrupt normal development. The haemodynamic abnormal placental circulation, which induced lack of oxygen supply and nutritional deficiency, implies the morphological pattern of the anomaly.  相似文献   
112.
BACKGROUND: Peridural fibrosis developing after lumbar discectomy may be responsible for as much as 20% of all Failed Back Surgery Syndrome. A variety of biological and non-biological materials have been used as a barrier to invasion of fibrous tissue into the vertebral canal. AIM: The purpose of this study was to evaluate the use of expanded polytetrafluoroethylene (ePTFE) surgical membrane (Gore-Tex membrane) to inhibit peridural fibrosis and reduce FBSS symptoms after lumbar discectomy. MATERIAL AND METHODS: In a prospective study we compared postoperative results in 20 patients who had an ePTFE membrane implanted during lumbar discectomy with the results in 20 patients in whom no material was implanted. The outcomes were evaluated using a questionnaire on activities of daily living according to the Low Back Outcome Score, pain grading scale -- Visual Analog Scale, assessment of Lasegue sign and MRI 18-24 months after the operation for all patients. RESULTS: The authors found no evident positive clinical and radiological effects of using ePTFE surgical membrane during lumbar discectomy. CONCLUSIONS: 1. It is impossible to prove that ePTFE membrane used during lumbar discectomy essentially prevents postoperative peridural scar formation. 2. The use of ePTFE membrane does not improve the outcome of the surgical treatment of lumbar disc herniation.  相似文献   
113.
AIM OF THIS PAPER: Is to present our results of surgical treatment of central region tumors in children and to determine prognostic factors for patients' survival. METHOD: Retrospective analysis of medical records, radiographies and histopathological specimens of patients treated at the Dept. of Neurosurgery with the diagnosis of central region tumor and review of questionnaires mailed to the patients' parents. The statistical analysis was performed using the "Statistica.pl" software. MATERIAL: From January 1980 to March 2003, 114 such children were treated (mean age--8.05 years, mean follow-up time--38.4 months). In the subgroup of benign tumors (n=70), 70% of children are still alive 21.4% are dead and no data are available for the remaining 8.5% (mean survival time--23 months). In the subgroup of malignant tumors (n=12), 33.3% of patients are still alive and 66.6% are dead (mean survival time--14.2 months). In the group treated surgically (total or partial resection) (n=35), 71.4% of children are still alive, 17.1% are dead and no data are available in 11.4% of cases (mean survival time--24 months). In the group of children who underwent palliative procedures only (n=47), 59.5% are still alive, 27% are dead and no data are available for the remaining 12.7% (mean survival time--18.3 months). The statistical analysis revealed highly significant differences in the survival of children dependent on the tumor grade (p=0.00059) and the extent of resection (p=0.00825). CONCLUSIONS: Tumors of the central region of brain in children are highly heterogenous, so in every case the histological diagnosis should be obtained. Prognostic factors are the degree of histologic malignancy and the extent of surgical resection. In every case surgical resection should be considered.  相似文献   
114.
Investigation of 3-hydroxy-3-methyl-glutaril-coenzyme A inhibitors (statins) has influenced considerably the process of treatment of dislipidemy; now they belong to the most frequently prescribed hypolipemizing medicines. As it has been proved through randomized clinical examination, it is believed to be related to their complex pharmacological action that statins cause certain clinical effects such as a decrease in the morbidity and mortality rate resulted from vessel diseases referred to artheriosclerotic changes. It has been also proved the statine's beneficial influence during the primary and secondary preventive treatment for ischaemic heart disease, ischaemic stroke in the case of patients with diagnosed changes in the vascular system. Moreover, it has been proved the clinical usability in the preventive treatment for osteoporotic changes in bones [4]. The aim of the preformulary examination is to determine solubilizing properties of oxyethylenated fatty alcohols of the Brij type in the relation to simvastatin. Estimation of pharmaceutical accessibility of simvastatin in model form of drug made it possible to establish the influence of supportive substances on the process of equilibrial solubilization of biologically active substance in the recipe liquid--0.1n HCl.  相似文献   
115.
In a retrospective analysis of 150 incompletely resected NSCLC patients treated with adjuvant external beam radiotherapy 32 (21.3%) survived 3 years with no symptoms of disease. Ipsilateral mediastinal/hilar lymph node involvement and macroscopic incomplete surgery were the prognostic factors that unfavourably influenced survival in Cox's proportional hazards model. Postoperative external beam radiotherapy was the efficient adjuvant treatment method in microscopically incompletely resected NSCLC, predominantly with no nodes involvement, but had no benefit in those with macroscopic incomplete surgery.  相似文献   
116.
Oxythiamin is one of the antivitamin derivatives of thiamin which, after phosphorylation, can be bound to the catalytic centre of thiamin-dependent enzymes and inhibit these enzymes. In this work the influence of oxythiamin on the growth rate, survival and the activity of pyruvate decarboxylase of Saccharomyces cerevisiae (s288c) was investigated. Oxythiamin decreased both the growth rate and survival ability of yeast cells. Moreover, in three-day-old cultures on a medium with oxythiamin, an increase of pyruvate decarboxylase activity was observed. This unusual effect may be in response to the earlier inhibition of pyruvate decarboxylase. A high concentration of pyruvate in the cell extracts taken from the medium with oxythiamin was found. This accumulation of pyruvate could provide for enhanced biosynthesis of the pyruvate decarboxylase apoform and an increase of enzyme activity.  相似文献   
117.
We report here on the exuberant glial reaction in the optic nerves affected by prion diseases. Optic nerves from CJD- and GSS-, and scrapie-infected mice and hamsters showed severe pathology. These lesions were qualitatively indistinguishable from each other but were more intense in the Fujisaki model than in the hamsters inoculated with Echigo-1. Exuberant cellular reaction comprised of macrophages containing numerous mitochondria, abundant rough endoplasmic reticulum, and secondary lysosomes filled with digested myelin debris, electron-dense material and occasionally, entire myelin-bound vacuoles were readily observed in both models. Macrophages actively digesting myelin fragments and containing lyre-like bodies and paracrystalline inclusions were frequently noted. Some macrophages extended long filopodia to form labyrinth-like structures, and within a few macrophages, concentric arrays of cisterns and channels sequestrated part of the cytoplasm. An analogous network of narrow cisterns was seen to surround whole segments of the myelinated fibers.  相似文献   
118.
Under ad libitum conditions, laboratory house mice (Mus domesticus) fragment considerable amounts of pelleted food and leave it scattered in their cages. The proportion of food thus wasted (in relation to food eaten) varies remarkably among individuals, from 2% to 40%, but is highly consistent in consecutive trials, even when the mice were moved from 22 to -10 degrees C and food consumption doubled. Food wasting did not differ either between the sexes or between genetic lines that had been selected (10 generations) for high voluntary wheel-running behavior (n=4) and their unselected control lines (n=4). However, it varied significantly among replicate lines within the selection groups and among families within the lines (coefficient of intraclass correlation for full sibs, rhof=0.41 in room temperature trials and rhof=0.34 in cold trials). Moreover, the percent of food wasted was negatively correlated with food consumption in the cold trials (males: r=-.36, females: r=-.20) and with total litter mass at weaning (the litters into which they were born; r=-.24), two traits that may affect Darwinian fitness. We conclude that food wastage should not be ignored without justification in calculations of food consumption. In addition, "table manners" can convey reliable information about family origin of an individual and its quality, and therefore could potentially play a role in establishment of social status.  相似文献   
119.
This article reviews the pathological mechanism of endometriosis. We concentrate on immunological and genetical factors which play a role in the developing of endometriosis. We present the possible network of interactions between immune cells, hormones and matrix metalloproteases system in the ectopic endometrial tissue.  相似文献   
120.
In the article authors present a new edition of computer programme managing active and population cytology screening in the selected group of women in Bialystok. All improvements came out of the slow date base transforming. From the other hand so called "2000 year mistake" was eliminated. In the previous programme single date transfer between only two PC terminals was possible. Additionally way of assignment of particular groups of women to proper out patient rooms districts also by the zip codes were presented. Process of creation of cytology invitations to all women participating in screening examination was accelerate. Increase effectiveness of screening examinations was available as a result of using a new edition of computer programme. Percentage of mistakes and exam expenses were also minimized. Two main cytology screening foundation, its active and population were achieved.  相似文献   
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