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111.
112.
Psammoma bodies are one of many choroid plexus aging changes which origin is still enigma for the scientists. During our investigation psammoma bodies were studied on 30 postmortem brains by light microscopy. They stained red with HE, and were PAS and AB PAS positive. The largest number of lamellas were stained blue with Mallory's connective tissue stain, except peripheral and next to the center lamella which stained red. During the aging, psammoma bodies became larger and more irregular, which was followed with group area and perimeter, single psammoma body average area and average perimeter, average diameter and contour index increase. Psammoma bodies mearged in the second and the third age group and mearging process led to larger and more irregular structures formation. The results of this investigation suggest that psammoma bodies are more frequent in choroid plexus of healthy older people and during the aging they obtain larger dimensions, more irregular contours, which is the result of their mutual mearging.  相似文献   
113.
Gaucher's disease is the most common lysosomal storage disorder. It was identified in 1882 by Phillipe Gaucher, a French dermatologist. However, it was not until 1965 that Gaucher disease was found to be due to a deficiency in the enzyme glucocerebrosidase (EC 3.2.1.45) which breaks down glucocerebroside, a cell membrane component. The deficiency in this enzyme leads to an accumulation of glucocerebroside within the lysosomes of macrophages throughout the body. Gaucher's disease is classified into three types: type 1 (non-neuronopathic), type 2 (acute neuronopathic), and type 3 (subacute neuronopathic). Of the three, type 1 is the most common, affecting one in 40,000-200,000 people and having a high prevalence among Ashkenazi Jews, affecting one in 450-1500. The signs and symptoms of type 1 disease demonstrate marked heterogeneity, from asymptomatic or mildly symptomatic, to severe disability with disfigurement and even death. Hepatosplenomegaly and thrombocytopenia are well documented. Less well-recognized are often insidious skeletal complications which affect the majority of type 1 patients and which are its most debilitating feature. In addition to clinical suspicion, some morphologic, hematologic and biochemical indicators can help establish the diagnosis. However, definitive diagnosis is only made by determining the catalytic activity of the lysosomal enzyme glucocerebrosidase. Confirmation of heterozygosity requires the use of molecular biotechnology methods. About 150 mutations of the glucocerebrosidase gene have been identified in patients with Gaucher's disease, some of which are predictive of phenotype. The history of treatment of Gaucher disease started with splenectomy and continued with bone marrow transplantation, before the recent introduction of safe and effective enzyme replacement therapy. In Croatia, nine patients with type 1 Gaucher's disease have been identified so far. Seven patients are on enzyme replacement therapy, and past results demonstrated significant improvement in all clinical symptoms, without development of any side effects. However, new treatments, such as substrate balance therapy and gene therapy, may become available within the next few years. The place, if any, that such therapies will have in the treatment of patients with Gaucher's disease will be dependent on the results of clinical studies currently in progress.  相似文献   
114.
This study was designed to examine whether anxious personality, i.e. trait anxiety, influences the autonomic nervous functions in humans without manipulation of experimental stressors. The degrees of state and trait anxiety, blood pressure, heart rate, pupillary light reflex (PLR), and body temperature were measured at the same hour on four different days in 14 healthy college students. A multiple regression analysis showed that trait anxiety predominantly influenced state anxiety and the PLR parameters. A single regression analysis showed that trait anxiety positively correlated to the initial pupillary diameter and the constricted diameter of PLR and negatively to the amplitude of PLR. It was concluded that trait anxiety predicts state anxiety and a smaller amplitude of PLR in humans at rest.  相似文献   
115.
Radionuclide-angiography (RNA_ left-to-right intracardiac-shunt quantification algorithms, based on the part-by-part fit technique and the use of a so-called gamma variate model function (GVF), were tested via simulation analysis using data obtained from normal subjects. A good bolus of radioindicator was obtained by administering it directly into the vena subclavia. Normal subjects were defined as those having pulmonary histograms (PH) with no visible distortion caused by a shunt. Pure, non-superimposed data on the downslope of the PH curves, which are lost in presence of a shunt, proved to be appropriate reference values for testing the accuracy of results of standard shunt quantification algorithms. A generalized four-parameter GVF was introduced in order to extend the flexibility of the model function. The use of the three-parametric GVF to reconstruct the downslope of the PH curve out of the upslope data proved to be inadequate. This reveals an evident source of error in algorithms that calculate the shunt contribution by fitting GVF parameters to so-called difference-curve data. It is concluded that the inherent restricted statistical weight of RNA data prevents accurate results being obtained from standard RNA-shunt-assessment algorithms.  相似文献   
116.
Acute (50.0 mg/kg) and repeated (0.1–10.0 mg/kg) administration of dihydroergosine (DHESN) to rats over 5 days lowered the concentration of 5-HIAA in the brain. DHESN given acutely increased the brain 5-HT in p-CPA-treated animals and diminished the probenecid-induced increase in brain 5-HIAA. In pargyline-treated rats DHESN enhanced the 5-HT/5-HIAA ratio. DHESN administered to rats repeatedly over 5 days decreased the level of 5-HT in blood platelets, and in vitro at concentrations of 10-4 M and 10-3 M inhibited the uptake of [14C]-5-HT in platelets. DHESN (10.0–100.0 mg/kg) potentiated the 5-HT syndrome produced in rats by pargyline and 5-HTP. This potentiation was blocked with cyproheptadine but not with haloperidol. DHESN (1.0 and 10.0 mg/kg) lowered the locomotor activity of rats and 10.0 mg/kg DHESN also reduced the duration of immobility in rats forced to swim in a restricted space. The results indicate that DHESN, like antidepressants, decreases the turnover of serotonin in the brain and potentiates the 5-HT-mediated behaviour. This might suggest that the drug should be further investigated for its potential antidepressive properties.  相似文献   
117.
As a crucial step towards understanding the mechanism of localisation of radiopharmaceuticals in specific target organs, the interaction of the radiopharmaceuticals 99mTc-DMS and 99Tc-DMS with blood serum proteins was studied. The interaction of 99mTc-DMS radiopharmaceutical was examined from two aspects: total protein binding as well as specificity of binding to certain classes of proteins.After in vitro labelling of human sera with 99mTc-DMS, the following values of bound radioactivity to total serum proteins were determined: 65%±3.2% by gel-filtration chromatography; 72%±4.6% by dialysis; while on the basis of precipitation by perchloric and trichloroacetic acid 72.7%±6.8% and 71%±2.3%, respectively. Distribution of 99mTc-DMS or 99Tc-DMS among serum proteins was analysed by agarose gel electrophoresis of the sera at pH 8.6 after in vivo and in vitro labelling of human sera with 99m-Tc-DMS, while the same analysis was performed with 99Tc-DMS complex after in vitro labelling of human and rat sera as well as after in vivo application to the rats.The results obtained demonstrate that carrier serum proteins investigated by agarose gel electrophoresis were in the migration zone of 2-, 1- and 1-globulins, whereas the radioactivity found in the serum albumin zone was negligible. Interaction of both Tc-DMS complexes with proteins was very similar, and this conclusion was in good correlation with our previously obtained results in investigations concerning the biochemical behaviour of these complexes.  相似文献   
118.
The effects of exogenous testosterone on various testicular variables has become of increasing significance because of its potential use in male contraception. For this reason, high doses of two testosterone esters [testosterone propionate (TP) and testosterone enanthate (TE)] were used in a study of their influence on the morphology, length and curvature of the seminiferous tubules of the rat testis, and on cytological smears of the seminiferous tubules epithelium. TP was given for 14 days (3 mg/100 g body weight, i. m.) to assess the acute effects of testosterone on the seminiferous tubules. TE was administered for 60 days (in the same manner as TP) to study possible chronic effects on the rat testis. After TP and TE treatment the seminiferous tubule epithelium showed disorganization and desquamation of spermatogenic cells. In the TP-treated testes the tubules lined with Sertoli cells only were observed. The values for the length and curvature of seminiferous tubules of the TP- and TE-treated rats were significantly reduced (p<0.001). All these changes were observed earlier in the TP-treated than in the TE-treated animals. In cytological smears of the testis of the TP- and TE-treated rats an increase of vacuoles and residual bodies in Sertoli cell cytoplasm was noted. In addition, a reduction of spermatogenic cells, particularly sperms, was manifest in the smears after treatment. Large groups of Sertoli cells were seen in the smears from these testes.The study was supported by a Grant for Scientific Research No. 3-01-041 from the Ministry of Science, Technology and Informatics of the Republic of Croatia  相似文献   
119.
We report the clinical and morphological features of a distinctive hepatorenal disorder in four patients and review the five similar patients in the literature. The main clinical characteristics were early onset of cholestatic liver disease and progressive tubulointerstitial nephritis leading to renal death in early childhood. Liver histology showed disturbed architecture with nodular and acinar formations and portal fibrosis and bile duct proliferation. Histological abnormalities in the kidney were severe interstitial fibrosis and tubular atrophy and dilatation, while the typical features of nephronophthisis were lacking. These clinical and morphological characteristics distinguish our patients from the majority described, as having nephronophthisis and congenital hepatic fibrosis or any other known syndrome with concomitant hepatorenel involvement. We suggest that the association of cholestatic liver disease and progressive tubulointerstitial nephritis represents a new syndrome.  相似文献   
120.
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