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3152. Biological and ecological studies on Scymnus syriacus and Scymnus levaillanti (Coleoptera: Coccinellidae)
- Creator:
- Allawi, Thabet
- Type:
- article, model:article, and TEXT
- Subject:
- Scymnus syriacus, Scymnus levaillanti, aphidophagous coccinellids, oviposition, developmental time, longevity, and food consumption
- Language:
- English
- Description:
- Both Scymnus syriacus Mars. and Scymnus levaillanti Muls. are aphidophagous coccinellids. In the laboratory they consumed and successfully reproduced on several species of aphids. Larvae suck the prey contents from aphid appendages, while adults consume the whole aphid, except for parts of the appendages. Extra-oral digestion is practiced during feeding. The mean number of aphids consumed by the larval stage of S. syriacus when reared at 25°C was 95, and 130 aphids at 30°C. For S. levaillanti it was 125 and 139 aphids at 25°C and 30°C, respectively. The mean number of eggs deposited daily by S. syriacus for the first three weeks of adult life was 19.5, with a range of 3-30 eggs at 25°C. Longevity of adults ranged from 3 to 4 months at 25°C and 2.5-3 months at 30°C.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3153. Biological effects of noble gases
- Creator:
- Růžička, J., Beneš, J., Lukáš Bolek, and Věra Markvartová
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, vzácné plyny, xenon, potápění, anestezie, noble gases, diving, anesthesia, argon, stroke, 14, and 612
- Language:
- English
- Description:
- Noble gases are known for their inertness. They do not react chemically with any element at normal temperature and pressure. Through that, some of them are known to be biologically active by their sedative, hypnotic and analgesic properties. Common inhalation anesthetics are characterized by some disadvantages (toxicity, decreased cardiac output, etc). Inhalation of xenon introduces anesthesia and has none of the above disadvantages, hence xenon seems to be the anesthetic gas of the future (with just one disadvantage - its cost). It is known that argon has similar anesthetic properties (under hyperbaric conditions), which is much cheaper and easily accessible. The question is if this could be used in clinical practice, in anesthesia of patients who undergo treatment in the hyperbaric chamber. Xenon was found to be organ-protective. Recent animal experiments indicated that xenon decreases infarction size after ischemic attack on brain or heart. The goal of our study is to check if hyperbaric argon has properties similar to those of xenon., J. Růžička, J. Beneš, L. Bolek, V. Markvartová., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3154. Biological effects of selenium compounds with a particular attention to the ontogenetic development
- Creator:
- Ivana Ošťádalová
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, development, selenium toxicity, cataractogenic effect, lethal effect, cardioprotective effect, 14, and 612
- Language:
- English
- Description:
- Selenium is a trace element that is essential for living organism. Its beneficial effect is, however, expressed in a very narrow dosage range: the high and low doses of selenium are connected with pathological manifestations. The toxicity depends on the chemical form of selenium, state of organism, interactions with heavy metals and on the stage of ontogenetic development. Whereas one dose of sodium selenite (20 μmol/kg b.w.) is lethal in adult rats, suckling rats are entirely resistant. However, within one week after administration of the same dose, cataract of eye lens developed. The highest incidence of cataract was observed in 10-day-old animals and it decreased until day 20. From postnatal day 20 to day 40 the rats were resistant to both the lethal and cataractogenic effects of selenium. The incidence of cataract may be suppressed by premature weaning, lower hydration of suckling, change of water soluble/water insoluble lens protein ratio, thyroxine treatment, and by interaction with mercury. By means of its oxidative and reduction properties, selenium is involved in the maintenance of the cell redox homeostasis. Typical example is its possible cardioprotective effect: selenium decreased number of arrhythmias, reduced infarct size and improved the contractile recovery after ischemia/reperfusion injury. Selenium supplementation may thus increase cardiac tolerance to ischemic damage., I. Ošťádalová., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3155. Biological effects of two successive shock waves focused on liver tissues and melanoma cells
- Creator:
- Jiří Beneš, Pavel Šunka, Jarmila Králová, Kašpar, J., and Pavla Poučková
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, rázové vlny, fyziologie, shock waves, physiology, focused shock waves, double shocks, cavitation collapse, secondary shocks, liver injury, 14, and 612
- Language:
- English
- Description:
- A new generator of two successive shock waves focused to a common focal point has been developed. Cylindrical pressure waves created by multichannel electrical discharges on two cylindrical composite anodes are focused by a metallic parabolic reflector - cathode, and near the focus they are transformed to strong shock waves. Schlieren photos of the focal region have demonstrated that mutual interaction of the two waves results in generation of a large number of secondary short-wavelength shocks. Interaction of the focused shockwaves with liver tissues and cancer cell suspensions was investigated. Localized injury of rabbit liver induced by the shock waves was demonstrated by magnetic resonance imaging. Histological analysis of liver samples taken from the injured region revealed that the transition between the injured and the healthy tissues is sharp. Suspension of melanoma B16 cells was exposed and the number of the surviving cells rapidly decreased with increasing number of shocks and only 8 % of cells survived 350 shocks. Photographs of cells demonstrate that even small number of shocks results in perforation of cell membranes., J. Beneš, P. Šunka, J. Králová, J. Kašpar, P. Poučková., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3156. Biological Half-life of Bromide in the Rat Depends Primarily on the Magnitude of Sodium Intake
- Creator:
- Pavelka, S., Babický, A., and Vobecký, M.
- Type:
- article, model:article, and TEXT
- Subject:
- Biological half-life, Bromide, Chloride, Sodium, and Rat
- Language:
- English
- Description:
- The parallel course of the excretion rates of bromide and sodium ions was demonstrated in adult male and female rats administered simultaneously with potassium 82Br-bromide and 24Na-sodium chloride. The animals were exposed to various intakes of sodium ions accompanied with five different anions: Br-, Cl-, HCO3-, ClO4-, and SCN-. Regardless of the anion accompanying the sodium ion, the excretion rates of 82Br- and 24Na+ ions were proportional to the magnitude of sodium intake in the animals. Hence, we have proved our hypothesis that the biological half-life of bromide depends on the magnitude of sodium intake rather than on the intake of chloride.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3157. Biological half-life of bromine in the rat thyroid
- Creator:
- Vobecký, M., Babický, A., Lener, J., and Pavelka, S.
- Type:
- article, model:article, and TEXT
- Subject:
- bromine, biological half-life, rat, thyroid, and I/Br ratio
- Language:
- English
- Description:
- The biological half-life of bromine in the rat thyroid was determined by measuring the radioactivity of thyroids of animals which continuously received 82Br labelled bromide in their food. The value of this half-life (110 h) is practically the same as the biological half-life of iodine. The rate of establishing the I/Br concentration ratio in the thyroid depends on the biological half-life of bromine. The mechanism of this process depends on the state of iodine supply. When the supply is sufficient, the iodine concentration in the thyroid remains constant, while during iodine deficiency the iodine atoms are replaced by atoms of bromine.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3158. Biological parameters of Duponchelia fovealis (Lepidoptera: Crambidae) reared in the laboratory on two diets
- Creator:
- Zawadneak, Maria A. C., Gonçalves, Rodrimar B., Poltronieri, Alex S., Santos, Bráulio, Bischoff, Adélia M., Borba, Aline M., and Pimentel, Ida C.
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, motýli, jahody, rozmnožování (biologie), butterflies, strawberries, reproduction, Lepidoptera, Crambidae, Duponchelia fovealis, European pepper moth, artificial diet, life cycle, development, biological parameters, 2, and 59
- Language:
- English
- Description:
- Duponchelia fovealis Zeller is a polyphagous insect that has been recently reported attacking strawberry plants (Fragaria x ananassa Duchesne). Despite its economic importance there are few studies on this pest because it is difficult to rear it in the laboratory. With a constant supply of insects, studies on alternative methods of pest control can be conducted. This study aimed at developing an artificial diet for rearing D. fovealis with biological characteristics similar to those reared on their natural diet. This study was carried out in a climate-controlled room (25°C ± 2°C, RH 70% ± 10%, and 14L : 10D). The natural diet consisted of 'San Andreas' strawberry leaves (D1), while the artificial diet (D2) was developed in which beans, casein, soy protein, yeast and wheat germ are used as sources of protein. Five instars were identified. D. fovealis completed its life cycle in 38 and 40 days when fed D1 and D2, respectively. Survival was highest for the larvae fed the artificial diet. Females fed D1 lay a mean of 300.2 ± 62.3 eggs, while those fed D2, 220.3 ± 41.8 eggs. The artificial diet is suitable for the continuous rearing of D. fovealis in the laboratory., Maria A. C. Zawadneak, Rodrimar B. Gonçalves, Alex S. Poltronieri, Bráulio Santos, Adélia M. Bischoff, Aline M. Borba, Ida C. Pimentel., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3159. Biological prognostic markers in chronic lymphocytic leukemia
- Creator:
- Vroblová, Vladimíra
- Type:
- model:article and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3160. Biology and immature stages of the clam-killing fly, Renocera pallida (Diptera: Sciomyzidae)
- Creator:
- Horsáková, Jana
- Type:
- article, model:article, and TEXT
- Subject:
- Sciomyzidae, Renocera pallida, clam-killing fly, rearing, life-cycle, egg, larva, puparium, and morphology
- Language:
- English
- Description:
- The larva of the Palaearctic Renocera pallida (Fallén, 1820) is confirmed as a predator of small species of bivalve molluscs of the family Sphaeriidae. To date only the larvae of three Nearctic Renocera species (and larvae of two other species of Sciomyzidae in two genera) are known to have the same food preference. The life cycle, biology, larval feeding and behaviour are described for the first time and compared with that of the Nearctic Renocera. The systematic position and biology of Renocera in general are discussed. Descriptions of the egg, second and third larval instars and the puparium of R. pallida are presented, the main features of the egg and larvae are illustrated by scanning electron micrographs.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public