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981.
Summary. Cytinus ruber (Fourr.) Fritsch is described and illustrated. Current knowledge of its phylogeny and systematics is discussed, and its successful cultivation is recorded. 相似文献
982.
983.
984.
We used a non-invasive TOBEC method (Total Body Electric Conductivity) to estimate lean body mass and fat content in mouse-eared batsMyotis myotis (Borkhausen, 1797) hibernating in Poznañ Forts (W Poland) and in a semi-natural cave-mine Miedzianka (SE Poland). In December, fat content averaged 5.5 g in females (body mass = 29.4 g) and 5.3 g in males (body mass = 28.4 g). At the end of hibernation (April), fat content averaged 2.2 g in females (body mass = 25.6 g) and 1.4 g in males (body mass = 23.7 g). Fat content did not differ between the localities either in December or in April, but the pattern of changes of fat content was different. We calculated the rate of energy expenditure in hibernating bats using two methods, based on independent samples (fat content in first-time captured individuals) and based on paired observations (changes of fat content in re-captured individuals), and discussed problems associated with the two approaches. Both methods show that the bats need about 4.9 g of fat (191 kJ) to sustain a 165-day hibernation. However, the rate of fat usage varied considerably between the sites and hibernation phase. Although the average amount of fat remaining in April would be sufficient to support at least six more weeks of hibernation, the level of reserves was close to zero in some individuals. 相似文献
985.
Dr. habil. B. Ceranka Dr. A. Dobek Dr. H. Kiełozewska 《Biometrical journal. Biometrische Zeitschrift》1987,29(4):455-460
The analysis of offsprings from the partial diallel crosses is presented. In considered type of crossing, p parental forms into H separate groups are devided. Single crosses among parental forms, from separate groups only, are performed. The analysis for experiments laid out in efficiency balanced block designs is given. 相似文献
986.
987.
Barbara Grzelakowska-Sztabert Małgorzata Balińska 《Biochimica et Biophysica Acta (BBA)/General Subjects》1980,632(2):164-172
Betaine when present in the culture medium could induce the activity of betaine: homocysteine methyltransferase (EC 2.1.1.5) in mouse L-cells, and leukemic L1210 cells, as well as in mouse embryo fibroblasts grown in vitro. We found this process to be time- and concentration-dependent. A persisting contact of the cells with betaine was indispensible for expressing and maintaining the enzyme activity. The treatment of cells with cycloheximide or actinomycin D abolished the process of induction. Methionine as well as homocysteine, when present either in the culture medium or in the reaction mixture, strongly depressed the activity of this enzyme. The L-cells with the induced betaine: homocysteine methyltransferase survived but did not multiply in the methionine-deficient medium, therefore, they did not become prototrophs with respect to methionine. 相似文献
988.
989.
Environmental factors play an essential role in the etiology of diseases of the hematopoietic system. Such factors include soil and water pollution and the presence of metals and toxic compounds in the air. Measuring the content of metallic elements in rainwater has become an accepted procedure for environmental pollution monitoring. In accordance with the above, it was decided to study relations between the content of selected elements in rainwater and hospitalization frequency due to chronic lymphocytic leukemia (CLL, C91 on ICD-10) and chronic myeloid leukemia (CML, C92 on ICD-10). It can be assumed that hospitalization frequency is a reliable indicator of exacerbations of these diseases. The annual average of hospitalizations due to a given disease during the years 2000–2002 was correlated with the annual average content of a given element in rainwater using the Spearman’s correlation indicator to describe the relationship between the element content and the disease that is possibly a consequence of the element’s presence in rainwater. In cases of CLL for all the subjected population and for men, no statistically significant correlations were found. For women, statistically significant correlations were found for chromium (r?=?0.66), lead (r?=?0.58), copper (r?=?0.58), and cadmium (r?=?0.51). For CML in all the studied population significant, negative correlations were found for magnesium (r?=??0.6) and zinc (r?=?-0.52). In men, significant negative correlations were seen for magnesium (r?=??0.69 and zinc (r?=??0.55). No significant correlations were found in women. These results indicate the need of taking into account the environmental and gender factors in research connected with these diseases, which can be probably of help in improvements of therapy efficiency. 相似文献
990.
Based on published information about the glacial, postglacial, and recent distribution of the root vole, Microtus oeconomus, we hypothesized that a population inhabiting the pristine wetland in eastern Poland (Bialowieza Primeval Forest) might comprise a high diversity of haplotypes. The support for this hypothesis was provided by an analysis of partial cytb gene sequences from 149 voles sampled within a two-hectare plot during a nine-year study. In this population, we identified eight haplotypes (PLB1–PLB8), four of which were new to the root vole. These haplotypes were characterized by low nucleotide diversity (π?=?0.0054, SE?=?0.0019), the absence of transversional differences between sequences, and no changes in the encoded amino acid sequence: features suggesting a lack of immigration from the distant populations. The haplotype number and their frequency distribution in males and females did not differ significantly. An assessment of the persistence of matrilines in the local population throughout the study period revealed that the haplotype composition was relatively stable for only about 3 years. A more complete haplotype network for root voles in Europe was constructed by combining the newly identified haplotypes with the 45 previously described haplotypes. Two of the haplotypes detected in this study occupy key positions in this network: PLB5, as the closest link to the North European group, and PLB8, as an ancestor to many other Central European haplotypes. 相似文献