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91.
J. B. Warchol Ch. Pilgrim W. J. Ginda R. Brelińska 《Histochemistry and cell biology》1988,88(3-6):571-573
Summary Wistar rats were injected intraperitoneally with 2-(14C)deoxyglucose and their thymuses were processed for thaw-mount autoradiography after 5, 10 or 35 min. Highest levels of radioactivity were demonstrated in the thymic medulla (5-fold higher than in the cortex). Scanning of autoradiograms for regional differences in grain densities indicated particularly intense glucose utilization in the cortico-medullary zone. Differences in glucose utilization between individual thymic zones seem to reflect differences in cellular composition, i. e., ratio of stroma cells to thymocytes.Dedicated to Professor Dr. T.H. Schiebler on the occasion of his 65th birthday 相似文献
92.
Our objective was to examine the developmental fate of sperm nuclei in oocytes fertilized under conditions of meiotic arrest. Therefore zona-free metaphase II oocytes and oocyte fragments (nucleate and anucleate) were fertilized in the presence of colcemid. In anucleate oocyte fragments, normal male pronuclei develop. In contrast, in intact oocytes and nucleate fragments sperm nuclei after initial decondensation undergo secondary condensation. This state is maintained as long as the oocytes are treated with colcemid. When the drug is removed 3 h after insemination, the meiotic spindle(s) is reconstructed, the second polar body(ies) is extruded, and a female pronucleus (or micronuclei) forms. At the same time the sperm nucleus decondenses again and transforms into a male pronucleus. In addition oocytes fertilized in the presence of colcemid could not be refertilized. These observations suggest that oocytes and oocyte fragments fertilized in the presence of colcemid undergo activation despite the failure of pronucleus formation. The inhibitory effect of colcemid on the formation of pronuclei is expressed only in the presence of oocyte chromosomes. We suggest that colcemid stabilizes factors responsible for chromosome condensation that are associated with oocyte chromosomes but not factors (whether the same or different) present in the cytoplasm. 相似文献
93.
J Lewin-Kowalik A L Sieroń M Krause J J Barski D Górka 《Acta physiologica Hungarica》1992,79(3):219-231
The present work has a twofold aim: 1. To ascertain whether the stimulative influence of peripheral nerve grafts on injured hippocampal neurons depends on the time lapse after transection and; 2. To examine whether the mentioned effect runs parallel to the time-dependent changes of proteins contents and composition in the submicrosomal fraction from transected rat sciatic nerves. Fluorescence microscope examination revealed that FITC-HRP labeled cells extending their neurites into the implanted peripheral nerve segments were particularly numerous among the hippocampal neurons when 7- and 35-day-old predegenegated distal stumps were used as grafts. Discontinuous SDS-slab polyacrylamide gel electrophoresis of submicrosomal fraction proteins obtained from distal stumps of rat sciatic nerves was performed at the 7, 14, 21 and 35 days after transection. Among the obtained protein fractions the most interesting seem to be the ones of 47 and 54 kDa, which reached maximal levels at the 7th day and the 50 kDa fraction with a maximum at the 35th experimental day. It is possible that the growth promoting power of the employed grafts depends on the presence of proper proteins. 相似文献
94.
W Zgliczyński S Zgliczyński A Makowska J S?owinska-Srzednicka J Janik W Jeske J Walecki 《Endokrynologia Polska》1992,43(3):242-249
Majority of pituitary tumours secrete one of the named hormones: PRL, GH, ACTH, proopiomelanocortine, alpha and beta subunit of TSH, LH, and FSH. Some of those tumours secrete two or more hormones. The aim of this study was to determine the effect of bromocriptine (Parlodel MR and LAR) upon secretion of hormones and tumour size in 10 patients with mixed pituitary tumours. In all patients pituitary and peripheral hormones, CT scan and visual fields were examined before and after treatment with bromocriptine: Parlodel MR and LAR. Bromocriptine treatment decreased PRL secretion in all 10 patients; GH--in all 6 in whom it was increased; TSH--in 2, FSH--in 2 and alpha-subunit in all 6 in whom they were increased. In 5 patients treatment resulted in shrinkage of the tumour mass by 20 to 35%. In all examined subjects clinical improvement was achieved. Our results demonstrate that bromocriptine (Parlodel MR and LAR) is very effective and well tolerated in the treatment of patients with mixed pituitary tumours particularly those with hyperprolactinemia. 相似文献
95.
Normal endothelin 1/2 levels and their correlation with age were evaluated. For clinical application of the endothelin 1/2 RIA test, optimum storage conditions were investigated. Plasma endothelin 1/2 (ET) levels were measured in 36 healthy blood donors, mostly males, of mean age 36 +/- 8 years, subdivided into three age groups: 17-30, 31-40 and above 40 years old. The mean normal ET levels in the three age groups, and corresponding standard deviations, were: 0.58 +/- 0.19, 0.62 +/- 0.31, and 0.80 +/- 0.28 fmol/ml, respectively. The mean ET level for the whole normal population was 0.66 +/- 0.28 fmol/ml. Only differences between mean ET levels for the first and last groups were statistically significant (p < 0.05). Differences between mean ET levels in smokers (53% of total population) and non-smokers, women and men, irrespective of age, were found not to be statistically significant. At this stage of our work, we conclude that other factors than age alone play a role in enhancing ET levels above the age of 41 years. In our study of optimum storage conditions for endothelin 1/2, we found that after one week of storage at -24 degrees C the mean level of ET measured in frozen plasma dropped to 85% of the initial activity, while after the same period the respective decrease in ET activity in frozen extracts was 49%. Over the next two weeks, ET levels in plasma and extracts dropped to 57% and 32% of "zero time" activities, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
96.
W Zgliczyński J Brzeziński A Brzezińska J S?owińska-Srzednicka J Walecki 《Endokrynologia Polska》1992,43(3):210-221
Hypopituitarism can be a result of various lesions of hypothalamus, pituitary stalk, or of the pituitary gland itself. The aim of the study was to assess the value of CT and MRI examinations in determination of the cause of hypopituitarism. Seventeen patients with hypopituitarism (9 women and 8 men) aged 22 to 61 years have been examined. In three cases growth deficiency was observed, 4 women had galactorrhoea, 4 patients had diabetes insipidus, 16 patients had supra-adrenal insufficiency, 14 had signs of hypogonadism and 10 hypothyroidism. In each case plasma concentrations of LH, FSH, PRL, TSH, alpha-subunit, ACTH before and after appropriate stimulation with TRH, metoclopramid, LH-RH, GRF or metyrapon were determined with RIA. Every patient was examined both with CT and MRI (0.5 T Toshiba MRT 50a). All 17 patients had abnormal MR images of hypothalamo-pituitary area, while only 10 of them had abnormalities in their CT scans. In remaining 7 patients the MRI revealed: three cases of congenital malformation of hypophyseal stalk, two cases of empty sella, one posttraumatic lesion of the stalk and one case of granulomatous infiltration of the stalk. We found MRI superior to CT in establishing the case of hypopituitarism. 相似文献
97.
Summary Each of the two ovaries ofCatajapyx aquilonaris is composed of seven segmentally (metamerically) arranged ovarioles. The two lateral oviducts that join and bear ovarioles extend throughout the abdomen. In the ovariole three regions can be recognized: the terminal filament, the germarium and the vitellarium. The terminal filaments do not fuse with each other but attach separately (by means of muscle fibres) to the closest lobes of the fat body. Germ cells in the germarium are not joined by intercellular bridges and do not form clusters. Thus the ovarioles ofC. aquilonaris are interpreted as being primarily panoistic. The results obtained support the hypothesis that both dipluran subgroups (Campodeina and Japygina) do not form a monophyletic unit. 相似文献
98.
M Lapiński K Stepniakowski A Januszewicz B Noszczyk E Szczepańska-Sadowska 《Journal of physiology and pharmacology》1992,43(1):65-78
The aim of the study was to find out whether vasopressin (AVP) modifies hypotensive and heart rate accelerating effects of atrial natriuretic peptide (ANP) in normotensive (WKY) and spontaneously hypertensive (SHR) conscious rats. The effect of i.v. administration of 1; 2 and 4 micrograms of ANP on blood pressure (MP) and heart rate (HR) was compared during i.v. infusion of 0.9% NaCl (NaCl), NaCl+AVP (1.2 ng kg-1 min-1) and NaCl+dEt2AVP (V1 receptors antagonist, 0.5 microgram kg-1 min-1). AVP increased MP in SHR and WKY and decreased HR in SHR. V1 antagonist decreased MP and increased HR only in SHR. In SHR ANP decreased MP and increased HR during NaCl, AVP and V1 antagonist infusion. In WKY these effects were observed only during AVP administration. In each experimental situation hypotension and tachycardia induced by ANP were greater in SHR than in WKY. In both strains ANP induced changes in MP and HR were enhanced during AVP in comparison to NaCl infusion. V1 antagonist did not modify effects of ANP in WKY and SHR. The results indicate that ANP abolishes hypertensive response induced by blood AVP elevation and that the basal levels of endogenous vasopressin acting through V1 receptors does not interfere with hypotensive action of ANP neither in WKY nor in SHR. 相似文献
99.
P Boroń R Flisiak E Bobrowska W Hilgier T Szpakowicz B Pytel 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1991,46(50-52):984-986
An effect of Aminosteril-Hepa intravenous infusions or plasmapheresis on selected amino acids, ammonia, alpha-aminonitrogen serum levels and serum GGTP activity was analysed in 28 patients with liver cirrhosis with and without hepatic encephalopathy. The patients were given protein controlled dietary treatment. It was found, that plasmapheresis exerted more potent effect on previously elevated ammonia and serum alpha-aminonitrogen levels as well as serum GGTP activity than intravenous infusions of Aminosteril-Hepa. It was clearly seen in patients with liver cirrhosis without hepatic encephalopathy. Aminosteril-Hepa intravenous infusions decreased serum glutamine levels to higher degree than plasmapheresis. Both types of therapy have had no significant effect on serum phenylalanine, tyrosine, and tryptophan levels in all patients. 相似文献
100.
W Mysiak L Stasiak M Elwertowski M Stopiński 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1991,46(43-44):818-821
Twelve patients with chronic renal failure treated with repeated dialysis underwent subtotal parathyroidectomy. Histologic examination revealed hyperplasia parathyroidal adenoma in all patients. Diagnostic correlation between bone X-ray, ultrasound of parathyroid glands, calcium deposits in cornea and conjunctiva, and histological findings has been analysed. Radiological abnormalities have been noted in 8 patients (66%), parathyroid glands hyperplasia in 9 (75%), and corneal and conjunctival calcium deposits in 10 (83%) patients. These data confirm the value of techniques under study for the diagnosis of the secondary hyperparathyroidism in patients with chronic renal failure. 相似文献