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91.
Vesna Čapkun Davor Eterović 《European journal of nuclear medicine and molecular imaging》1985,11(4):120-122
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
92.
Isolation and partial characterization of neurofibrillary tangles and amyloid plaque core in Alzheimer's disease: immunohistological studies 总被引:9,自引:0,他引:9
P D Gorevic F Go?i B Pons-Estel F Alvarez N S Peress B Frangione 《Journal of neuropathology and experimental neurology》1986,45(6):647-664
Fractions enriched in neurofibrillary tangles (NFT) and amyloid fibrils were isolated from the cerebral cortex of three cases of senile dementia of the Alzheimer type. Distilled water suspensions of these fractions were excluded from all pore size gels and resisted digestion with various proteolytic enzymes. Formic acid/chloroform treatment of each fraction resulted in the appearance of 4,000-6,000, 15,000-17,000 and 24,000 molecular weight proteins, with concomitant diminution in the amount of excluded material at the top of each gel. The 4,000-6,000 dalton band was best seen in fractions containing randomly arranged amyloid fibrils, and its amino acid composition resembled that of the recently reported "beta" protein. A polyclonal antiserum to purified NFT reacted with tangles in neurons and in dystrophic neurites around plaques by immunoperoxidase staining. No reaction was obtained with cerebrovascular or plaque core amyloid immunohistologically, or with the 4-6 kD protein on immunoblots. Cross-reactivity with the neurofibrillary lesions occurring in Pick's disease, progressive supranuclear palsy, postencephalitic Parkinsonism and dementia pugilistica was also seen. Specific binding of this antiserum to the double filamentous structure was confirmed by immunoelectron microscopy. Although the presence of "beta" protein in both NFT and amyloid-containing fractions suggests that it may be an important constituent of both, cross-contamination cannot be excluded. 相似文献
93.
94.
A. Bass J. Teisinger P. Hnik E. V. Macková R. Vejsada I. Eržen 《Pflügers Archiv : European journal of physiology》1984,400(2):188-193
Muscle hypertrophy was induced in the soleus muscle of young rats by tenotomy of the gastrocnemius and plantaris muscles. Three and 7 days afterwards the sciatic nerve was sectioned. The loss of weight of muscles subjected to this combined procedure three days after denervation was 30–40%. Lysosomal enzyme activities (acid phosphatase, -glucosidase, -galactosidase and N-acetyl--d-glucosaminidase) and energy enzyme activities (lactate dehydrogenase, LDH, triose-3-phosphate dehydrogenase, TPDH,d-hexokinase, HK and citrate synthase, CS) were determined 3 days after denervation, 3, 7 and 10 days after hypertrophy had been induced and 3 days after denervation of hypertrophying muscles on day 3 and 7. Normal non-operated rats of corresponding body wieght served as controls and their enzyme activities were estimated on the same day. In the course of muscle hypertrophy, the 4 lysosomal enzyme activities increased progressively. Although 3 days' denervation of control muscles did not alter lysomal enzyme activities, denervation of hypertrophying muscles greatly enhanced the activity of these enzymes. Enzymes of energy metabolism were affected to a lesser degree. The results suggest that denervation of hypertrophying muscles causes more extreme changes in muscle weight and lysosomal enzyme activities than denervation alone. The possible implications of this finding are discussed in relation to the rapid atrophy. 相似文献
95.
Davor Ježek Ljerka Šimunić-Banek Ružica Pezerović-Panijan 《Archives of toxicology》1993,67(2):131-140
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
96.
Milana Popović-Rolović Mirjana Kostić Miodrag Sindjić Olga Jovanović Amira Peco-Antić Divna Kruščić 《Pediatric nephrology (Berlin, Germany)》1993,7(4):396-400
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
97.
98.
多烯脂肪酸对脑血栓伴高脂血症病人降脂作用的疗效观察 总被引:2,自引:0,他引:2
目的:研究多烯脂肪酸胶囊对脑血栓伴高脂血症病人的降脂作用。选血脂康作对照。方法:60例脑血栓伴高脂血症病人随机分为二组:治疗组(n=31)及对照组(n=29)。服药前及服药后4周,8周查血脂。结果:⑴服药4周后TC和LDL-C分别降低21.02%和28.93%(多烯脂肪酸组)。⑵多烯脂肪酸组降低了34.06%的血清TG水平,效果显,结论:多烯脂肪酸胶囊降TG和LDL-C水平与血脂康作用相近,其降 相似文献
99.
P53 overexpression as an indicator of overall survival and response to treatment in osteosarcomas 总被引:5,自引:0,他引:5
Pápai Z Féja CN Hanna EN Sztán M Oláh E Szendrôi M 《Pathology oncology research : POR》1997,3(1):15-19
The p53 gene located at chromosome 17pl3 is found to be altered (allelic loss or other mutation) in multiple human cancers,
including osteosarcomas. The mutated gene produces a protein with a prolonged half-life thus rendering it detectable by conventional
immunohistochemistry. We examined the correlation between p53 expression and clinical prognosis as well as response to therapy.
Twentyone patients with previously untreated and histologically verified highly malignant osteosarcoma were used for this
study. Biopsy material taken both prior to the start of COSS 91 protocol and at the time of surgery (ten weeks later) was
examined for alterations in p53 protein expression and drug resistance. Two patients who had strong (+++) p53 protein expression
and three others who became positive during the chemotherapy had significantly worse prognosis (all of them died within one
year) than those who showed no p53 expression both at biopsy and after chemotherapy (all 11 patients are alive, average follow-up
time: 3.5 years). All patients who showed any kind of positive p53 protein expression on initial biopsy were non-respon-ders
to chemotherapy. In contrast, 69% (9 out of 13) of those who exhibited no p53 expression on initial biopsy were responders
or intermediate responders to chemotherapy. We concluded that p53 expression may be a useful prognostic factor in osteosarcomas.
The direct correlation between p53 positive expression and resistance to therapy can help in identifying patients who are
in need of a more vigorous or different chemotherapeutical protocol. 相似文献
100.
Summary Paralytic dislocation of the hip in cerebral palsy may be prevented by soft tissue surgery and the results of two procedures are reported. Twenty hips were treated by adductor tenotomy alone and this was unsuccessful in every case. An alternative method was carried out in 42 hips in 25 patients. The procedure combined adductor tenotomy with release of the hip muscles including iliac crest resection, tenotomy of the rectus femoris, recession of the iliopsoas and, when necessary, either release or transposition of the knee flexors. This was much more successful in decreasing migration of the femoral head.
Résumé Dans la paralysie cérébrale la luxation de la hanche peut être efficacement évitée grâce à des interventions chirurgicales portant sur les parties molles. Nous avons étudié les résultats de deux types d'opération: la ténotomie des adducteurs et cette même opération associée à la désinsertion de la hanche (avec transposition du psoas sur la partie proximale de la capsule) et éventuellement avec allongement des fléchisseurs du genou ou transposition de ceux-ci sur la partie distale du fémur. Soixante-deux hanches ont été opérées chez 45 malades. Les résultats de la ténotomie isolée des adducteurs ont été insuffisants dans les 20 cas opérés (âge moyen au moment de l'opération, 4, 5, ans, recul 6,5 ans). Les résultats du deuxième type d'intervention ont été meilleurs dans les 42 hanches opérées, le pourcentage migratoire de la tête fémorale a été réduit de 45% (âge moyen lors de l'opération 7 ans, recul 5 ans). Plus de la moitié des malades étaient capables de se déplacer.相似文献