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2.
The finger and palmar prints of 60 women with breast carcinoma were studied. The results were compared with two groups of healthy women, the first consisted of old women and the second of young women. The dermatoglyphics seem to be of little use in the diagnosis of cancers of ectodermic origin. Supported by M.P.I. 60%, 1983  相似文献   
3.
For the first time ever, the International Union for Conservation of Nature Red List Index for habitat types was calculated for an entire country, Finland. The RLIs were based on species threat assessments from 2000 and 2010 and included habitat definitions for all 10,131 species of 12 organism groups. The RLIs were bootstrapped to track statistically significant changes. The RLI changes of species grouped by habitats were negative for all habitat types except for forests and rural biotopes which showed a stable trend. Trends of beetles and true bugs were positive in rural and forest habitats. Other 16 observed trends of species group and habitat combinations were negative. Several trends observed were in accordance with studies focusing on particular taxa and habitats, and drivers for their change. This study demonstrates the usefulness of the RLI as a tool for observing habitat change based on species threat assessment data.  相似文献   
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Summary Chromosome fragile sites are inducible by aphidicolin in cultured human lymphocytes. To assess the frequency and distribution of these common fragile sites in the general population, a cytogenetic survey was performed on 126 subjects, 59 males and 67 females, whose age ranged from 1 day to 72 years. Common fragile sites, induced by aphidicolin, were widespread and showed a remarkably different sensitivity among individuals; age influenced the overall frequency of fragile sites. Moreover, both age and sex seemed to modulate the expression of specific fragile sites. In our population, the most common fragile sites were: 3p14, 16q23, Xp22, 6q26, 1p31, 4q31, 1p22, 7q22, 2q33, 3q27, 2q31, 7q32, 14q24, 10q22, 5q31, 2q37, 6p21.  相似文献   
6.
Synopsis Swimming speed and swimming path of goldfish and tetra larvae were studied in aquaria containing food patches composed of decapsulated cysts and immobilized nauplii of Artemia salina or sparsely distributed prey. The mean swimming speed of starved larvae in the medium without food was about four times higher than the speed of larvae feeding in a patch. Satiated larvae swam about 1.5 times slower than hungry fish. Consumption of single prey items by starved larvae caused the following sequence of swimming responses: handling pause (cessation of swimming), slow swimming in a restricted area, and fast swimming (approximately twice as fast as hungry larvae before encountering food) accompanied by a widening of the area searched (area increased searching). Mean swimming speed was constant over a broad range (101–103 ind·1–1 of food density, although at extreme (high or low) values of food density it depended on swimming responses of the predator. Frequency of visits to the different parts of the aquarium strongly depended on encounters of hungry fish with food particles or patches.  相似文献   
7.
Summary Monoclonal antibodies directed against the cholinergic binding site of the acetylcholine receptor were found to alter the ion channel properties in cultured chick myoballs. Time and dose dependent reduction in acetylcholine sensitivity was observed. Noise analysis experiments indicated a decrease in the mean single channel conductance and an increase in the mean single channel open time.  相似文献   
8.
The authors studied changes in the synthesis of nucleic acids (RNA, DNA) and protein by a mesophilic strain ofEscherichia coli B and a psychrophilic strain ofPseudomonas fluorescens at a low incubation temperature giving tenfold prolongation of the generation time. It was found that lowering the incubation temperature was followed by an increase in the intracellular nucleic acid content during the lag phase and the phase of accelerated growth, in which maximum nucleic acid (NA) values were reached. As a result, the total NA level in the cell also remained relatively high during further proliferation, when the increase in NA (particularly RNA) slows down at low incubation temperatures. Proteosynthesis, however, fell in the mesophilic culture. The smaller effect of a lowered temperature on DNA biosynthesis was manifested specifically in the lag phase ofEscherichia coli, in which disproportion developed between the amount of DNA (which was synthesized at a relatively higher rate) and RNA; this was afterwards equalized by a temporary break in DNA production. Pronounced differences in the given types of biosynthesis were found only in the mesophilic culture, while at suboptimal temperatures the metabolism of the psychrophilic strain slowed down but no marked changes occurred.  相似文献   
9.

1. 1. Isolated cardiac myocytes of perch, Perca fluviatilis, were kept in culture conditions for 1–2 months at 12 or 22°C. In the culture most myocytes flattened, lost their spindle-shaped morphology, protruded pseudopod-like branches and many of them started visible contractions in 1–2 weeks and continued beating for several months. Myocytes did not divide in the sparse cell population used. Typical intracellular structures could be seen in electron micrographs still after 1–2 months, but the sarcoplasmic organization became gradually more irregular in the culture.

2. 2. Beat rates showed linear temperature relationship on the Arrhenius plot. Myocytes cultivated at 22°C showed higher frequencies and slightly less dependence on temperature than myocytes cultivated at 12°C (apparent activation energies (Ea) 86 and 107 kJ/mol, respectively).

3. 3. Temperature dependence of frequencies was related to the presence of added serum or adrenergic agonists: β-adrenergic agonists increased the frequencies and rendered the cells less dependent on temperature; apparent activation energy was 43 kJ/mol for isoprenaline or adrenaline and 108 kJ/mol for noradrenaline and control group.

4. 4. Heat tolerance was greater in myocytes cultivated at 22°C than in myocytes cultivated at 12°C, and the change in tolerance appeared in 12 h after the alteration of culture temperature and the increased tolerance was persistent after that.

5. 5. It is suggested, that the processes of quick heat-hardening and of slower but persistent heat resistance acclimation developed in these cells in culture conditions but not the capacity acclimation, which seems to be dependent on adrenergic regulation of beat rate.

Author Keywords: Cardiac myocytes; cell cultivation; acclimation; thermotolerance; fish heart; Perca fluviatilis  相似文献   

10.
In the Baltic Sea area, the cladoceran Daphnia magna is commonly found in brackish water rockpools and it has been suggested that salinity is one of the niche dimensions that affects the distribution of the species. The salinity tolerance of D. magna was studied both in physiological and life history experiments. The experimental salinities were freshwater, 4S and 8S. The highest respiration and ammonium excretion rates were measured in the freshwater treatment with decreasing respiration and ammonium excretion rates at higher salinities. The lowest O/N ratio (oxygen consumption to ammonium excretion), describing the metabolic status of an organism, was obtained at 8S, although the only significant differences were detected when comparing to 4S treatments. Individual growth rate, reproductive output and population growth rate were highest at 4S. At 8S growth and reproduction were reduced as compared to freshwater and 4S. The life history parameters in the performed experiments indicated higher fitness (expressed as r) as well as more favourable conditions for growth and reproduction at 4S, whereas the O/N ratio was more difficult to interpret and, in this case, gave a less clear picture of the salinity influence.  相似文献   
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