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51.
This paper presents the results of taxonomic investigation of 8 species of lichens with gyalectoid apothecia collected in North-India and Nepal. Four species are recognized as new:Dimerella isidiata (sp. nova),D. nepalensis (sp. nova),Gyalideopsis lithophila (sp. nova) andRamonia nepalensis (sp. nova). Four species are reported for the first time from Nepal:Coenogonium moniliforme, Gyalectidium caucasicum, Gyalidea lecideopsis andG. scutellaris. 相似文献
52.
Summary The presence of 1% agar in the fixation and substrate solutions for the histochemical demonstration of thiamine pyrophosphatase (4.4 mM TPP; 3.6 mM Pb2+; 0.025 Tris-maleate buffer, pH 7.2) clearly facilitates the localization of the enzyme in Golgi apparatus in cold microtome sections prepared from unfixed specimens. 相似文献
53.
Antonín Vězda 《Folia Geobotanica》1978,13(1):99-102
Eine nèue foliikole Flechte (Pleurotrema epiphylla sp. n.) aus Zaïre (Zentral-Afrika) wird beschrieben. Die systematischen Beziehungen der neuen Art zu den anderenPleurotrema-Arten und die Stellung der GattungPleurotrema innerhalb der FamilieParatheliaceae wird kurz diskutiert. 相似文献
54.
The production of ε-pyrromycinone glycosides inStreptomyces galilaeus increased 12-fold, with respect to the wild strain, as a result of a sequential procedure including both natural selection
and treatment with mutagens (nitrous acid, UV light and γ-irradiation). Nitrous acid exhibited the highest mutagenic effect,
both in increasing the productivity and in inducing blocked mutants. A mutant strain blocked in the biosynthesis of glycosides
and accumulating free ε-pyrromycinone as the principal metabolite was obtained. 相似文献
55.
Anthracyclines 总被引:2,自引:2,他引:0
56.
Storage proteins of the seeds (cotyledons) of the South-American speciesPhaseolus caracalla were compared by means of immunoelectrophoretic methods with other representatives of the genusPhaseolus. These proteins most resemble the proteins of the co-called tropical group (i.e. Ph. atropurpureus, Ph. geophilus, Ph. bracteatus, Ph. semierectus) and least the so-called American endemites (Ph. vulgaris, Ph. coccineus, Ph. acutifolius, Ph. lunatus), the main globulin of which is of a completely different specificity. The proteins ofPh. caracalla are less similar to the group of the so-called Asiatic species (Ph. aureus, Ph. calcaratus, Ph. angularis, Ph. aconitifolius, Ph. trilobus) including the analyzed representatives ofVigna sinensis; their main globulin is only partly similar to that ofPh. caracalla. Some considerations on the relationship ofPh. caracalla with the so-called tropical species is presented. 相似文献
57.
The changes in intracellular oxygen tension and energy metabolism of the cat brain cortex were studied by surface fluororeflectometry during haemorrhagic shock. The results may be summarized as follows. (a) Intracellular oxygen tension, i.e. the maximum cortical NAD reduction obtained during nitrogen gas inhalation decreased gradually during the hypovolaemic phase of shock and finally, the brain cortex became ischaemic. (b) Partial uncoupling of the cerebrocortical mitochondrial respiration and oxidative phosphorylation appeared in the very early period of bleeding, as indicated by the overshot of the cortical NAD/NADH redox state towards oxidation subsequent to the cessation of nitrogen gas inhalation. Partial uncoupling of mitochondrial respiration and oxidative phosphorylation became more pronounced during the later phases of bleeding, finally, the mitochondrial electron transport stopped. In line with these changes the frequency and the amplitude of ECoG decreased gradually and markedly during the hypovolaemic phase of shock. (c) Microcirculation and energy metabolism of the cat brain cortex were severely and irreversibly damaged during the hypovolaemic phase of shock. This was clearly shown by the fact that in the majority of experiments the nitrogen anoxia after reinfusion failed to bring about changes in the cortical NAD/NADH redox state and the ECoG changes occurred during bleeding did not improve after reinfusion. It is concluded that the early disturbances of cerebrocortical energy metabolism play an important role in the development of neural and vascular lesions of the brain that occur during haemorrhagic shock. 相似文献
58.
Effect of oestradiol (E2) and progesterone (P) on activator calcium binding was studied in the rabbit uterus. Superficial Ca-binding of isolated uterine strips was characterized by determining the rate of loss of isometric tension evoked by low (2.4 V/cm) field strength electrical stimulation in Ca-free Krebs solution. Intramuscular injection of 10 mg P increased superficial Ca-binding significantly in the postpartum and E2-treated virgin uterus with a latency period of 8--12 hours. Bilateral ovariectomy on the 25th day of pregnancy decreased superficial Ca-binding progressively, which could be avoided by P-substitution. 72 hours after ovariectomy P-treatment failed to increase Ca-binding. Local application of cycloheximide increased Ca-binding in the E2-treated virgin uterus. The results suggest that a high P-level plays an important role in the induction and maintenance of a strong binding of superficial activator calcium in the rabbit uterus. Progressive disappearance of the strong binding near term and after bilateral ovariectomy correlates well with P-withdrawl in this species. 相似文献
59.
Calcium content and distribution of the 25-day pregnant (PR) and post partum (PP) rabbit uterus was studied by atomic absorption spectrophotometry and 45Ca determination. Total Ca content [2.28 +/- 0.28 (PR) and 2.19 +/- 0.12 (PP) mM/kg wet wt] extracellular [1.21 +/- 0.09 (PR) and 1.25 +/- 0.11 (PP) mM/kg wet wt] cellular [1.07 +/- 0.08 (PR) and 0.94 +/- 0.09 (PP) mM/kg wet et], total exchangeable [1.86 +/- 0.11 (PR) and 1.84 +/- 0.09 (PR) mM/kg wet wt] and inexchangeable [0.43 +/- 0.05 (PR) and 0.35 +/- 0.04 (PP) mM/kg wet wt] Ca fractions were identical in the two extreme endocrinological conditions. In contrast compartment size and rate constant of different exchangeable Ca fractions determined by kinetic analysis of 45Ca desaturation "urves (curve-peeling tecnique and computer method), revealed significant differences between PR and PP uteri. Two exchangeable phases could be identified in both endocrinological states. The rate constants of both phases of efflux were significantly higher in the PP (alpha 1 = 0.173 +/- 0.02 min-1; alpha 2 = 0.023 +/- 0.001 min-1) than in the PR uterus (alpha 1 = 0.099 +/- 0.01 min-1; alpha 2 = 0.018 +/- 0.01 min-1). Compartment size of phase 1 (fast component) was significantly higher in the PR (1.13 +/- 0.1 mM/kg wet wt) than in the PP uterus (0.77 +/- 0.06 mM/kg wet wt). In contrast, compartment size of phase 2 (slow component) was significantly smaller in PR than in PP uterine strips (0.74 +/- 0.06 and 1.08 +/- 0.11 mM/kg wet wt). The last portion of desaturation curves represents efflux from one homogenous compartment. The present results suggest that endocrinological control of the rabbit myometrium is linked to the regulation of the binding of a superficial exchangeable Ca fraction. 相似文献
60.
M. Podojil M. Blumauerová V. Přikrylová Z. Vaněk G. F. Gauze T. S. Maksimova 《Folia microbiologica》1980,25(6):464-466
The strainStreptomyces griseoruber 4620 produces, besides the anthracycline antibiotics beromycins, some other anthracyclines of the rhodomycin type. Twelve
isolates exhibiting a higher antibiotic activity (up to 2.5×), as compared to the parent strain, were obtained after a spontaneous
selection. The following species were isolated from the hydrolysate of mycelial extract: β-rhodomycinone, β-isorhodomycinone,
α2-rhodomycinone and 10-deoxy-β-rhodomycinone, which has not yet been described. 相似文献