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We have observed that sperm quality parameters indicative of spermatozoa hyperactivation such are lower “linearity” and “straightness”, and as showed by this research “elongation”, were more pronounced in patients with normal spermiogram compared to the group of men with reduced sperm motility who were undergoing routine in vitro fertilisation. The research encompassed 97 men diagnosed with normozoospermia (n = 20), asthenozoospermia (n = 54) and oligoasthenozoospermia (n = 23). The findings indicate that sperm quality of patients with normal spermiogram diagnosed according to WHO criteria, may be compromised by showing premature spontaneous hyperactivation which can decrease the chances of natural conception. We assessed synergistic effects of multiple chemical elements in ejaculated semen to find if premature spontaneous hyperactivation of spermatozoa can be a sign of imbalanced semen composition especially of elements K, Ca, Cu and Zn. Human semen samples showing low or high baseline status of chemical elements concentrations were found in samples from all three diagnostic groups. However, correlation of K/Ca and Cu/Zn ratios, taking into account samples from all three groups of men, were negative at statistical significance level p = 0.01. We tested if the negative correlation between K/Ca and Cu/Zn ratio works for greater number of semen samples. We found the negative correlation to be valid for 175 semen samples at statistical significance of p = 0.00002. The ratio of K/Ca and Cu/Zn, i.e. increased concentrations of K and Zn in comparison to concentrations of Ca and Cu, were associated with a decrease of “straightness” in the group of men with normal spermiogram and pronounced spontaneous hyperactivation of spermatozoa, implying that these elements act in synergy and that the balance of elements and not their absolute concentrations plays the major role in premature spermatozoa hyperactivation in ejaculated semen.  相似文献   
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The level of urine selenium in healthy adult population, 230 persons, was examined. Persons were selected regarding sex, ages, and smoking habits. No differences versus these observations have been found. For a total, group values are 16.96 Se nmol/creatinine mmol, SD=5.44. It is possible from a single-void specimen to express daily excretion of selenium.  相似文献   
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Summary The paper discusses the problems of genetic aspects of plant mineral nutrition in the light of the results presented at the First and Second Symposia on ‘Genetic Aspects of Plant Mineral Nutrition’ organized in Beograd in 1982 and Madison in 1985, respectively. On the basis of the results, future directions of research are discussed. The papers deal with the concentration and content of mineral nutrients in different genotypes, physiological and biochemical aspects of the genetic specificity of plant mineral nutrition, relations between plant genotypes and nitrogen fixing micro-organism strains, as well as with some related problems which have been investigated to a lesser extent. Particular attention is paid to papers and problems referring to genetic and breeding research work linked with genetic aspects of plant mineral nutrition as well as the possibilities of developing new cultivars requiring certain soil and mineral nutrition conditions for their cultivation.  相似文献   
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In the lichen genusUsnea different species ofTrebouxia-phycobionts as well as different haustorial types are known. The isolated and cultivated phycobiont ofUsnea longissima Ach. was studied by light- and electron microscopy and resembles in cytomorphological details the type ofTrebouxia impressa Ahmad. In addition to simple wall-to-wall contacts between the symbiotic components also intraparietal (=intrawall-)haustoria could be observed as the normal interaction type.
Frau Prof. Dr.Elisabeth Tschermak-Woess zu ihrem 70. Geburtstag gewidmet.  相似文献   
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Studies of the morphological features of the temporal region of mesolithic skulls from Padina in the Iron Gate Gorge of the Danube revealed a very prominent and large supramastoid ridge which is the most striking feature in skulls of both sexes. Mastoid processes were larger in male skulls, but in 25% of the cases there was an overlap between the size of the processes in male and female specimens. The mastoid ridge was prominent in both sexes. The digastric fossa was always well defined in both sexes and in the two thirds of the skull specimens it was deep. The posterior root of the zygoma was prominent in all the skulls, but it was better developed in the male specimens. The parietotemporal suture in both sexes rises above the level of the pterion. There were no morphological or anthropometrical differences between the left and the right side of individual skulls outside the limits of natural asymmetry. All these morphological characteristics of the temporal region may help in racial and sexual diagnosis of the Mesolithic skulls from the Iron Gate Gorge.  相似文献   
8.
1. The electric organ of Torpedo nobiliana contained putrescine (PUT), spermidine (SPD), spermine (SPM), and cadaverine (CAD). Traces of acetylated SPD and SPM were occasionaly seen. 2. Upon fractionation of the tissue by differential centrifugation, the polyamines (PA) were found predominantly in the soluble fraction. The postsynaptic membrane fraction, containing a high concentration of acetylcholine receptor (AChR), was proportionally enriched in SPM. The molar ratio of SPM to AChR was approximately two in these membranes. 3. The effect of exogeneous PA on AChR function was studied by two methods: carbamoylcholine (CCh)-dependent 86Rb+ influx into receptor-rich membrane vesicles and [alpha-125I]bungarotoxin (Bgt) binding to the AChR. 4. SPM inhibited both ion influx and the rate of Bgt binding at concentrations above 1 mM, and therefore it appears to act as a competitive antagonist of the AChR. 5. At submicromolar concentrations, and only after preincubation with the receptor-rich membrane, SPM and PUT increased the ion influx by about 20% over control values. 6. Preincubation with 100 nM SPM did not affect the equilibrium binding of iodinated toxin or the rate of toxin binding, and therefore SPM was not uncovering new receptors. 7. By measuring the initial rate of toxin binding after different periods of preincubation with 1 microM CCh, the rate of the slow phase of receptor desensitization was determined. This rate was not changed by 100 nM SPM. 8. Although these results suggest that at low concentrations SPM is a positive modulator of the AChR, the precise mechanism of action is not determined yet.  相似文献   
9.
Summary A study was undertaken to find the frequency of the F508 deletion and those of the G551D, R553X and G524X mutations among the mainly Slavic population of Serbia, Bosnia, Herzegovina, and Montenegro and compare the frequencies determined with those in other European populations. The F508 mutation was found to account for about 70% of CF genes in central Jugoslavia, where its frequency is significantly higher than elsewhere in Southern European populations.  相似文献   
10.
Single and repeated intravenous administration of cyclophosphamide significantly decreased the candidacidal activity of rabbit peritoneal macrophages. Using higher doses of the drug, a more pronounced decrease, persisting up to 10 d, was observed. The phagocytic index has not changed significantly 10 d after cyclophosphamide injection as compared with controls. No changes in the phagocytic activity were recorded. The decreased candidacidal activity may be one of the causes of serious microbial infections in cyclophosphamide-treated patients.  相似文献   
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