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The effect of explant type on somatic embryogenesis induction in Pisum sativum (cv. Oskar and an unregistered line HM-6) was studied. Shoot apices, leaf primordia, and epicotyl fragments of axenically grown, etiolated seedlings, as well as embryonic axes and cotyledon fragments isolated from zygotic embryos at different stages of development, were used as explants. Somatic embryogenesis was induced essentially as described by Griga in 1998 – MS salts and sucrose, B5 Gamborg vitamins, picloram (2.5 μM). After induction period (14 days) all cultures were transferred to the differentiation medium (basal medium as above, auxin omitted). Both in Oskar and HM-6, only shoot apices developed somatic embryos and (with significantly lower frequency) adventitious shoots.
This study was aimed at developing an efficient protocol for regeneration of Pseudostellaria heterophylla plantlets and induction of polyploidy. Calli of P. heterophylla (Miq) from stems, leaves and buds as explants could not differentiate into plantlets. However, young embryo segments used as primary explants produced embryonic calli on MS medium containing 5.0 mg/L 2,4-D and 0.5 mg/L KT. After the embryonic calli with granular protuberances were transferred to MS medium containing 0.5 mg/L BA, they developed shoots and then rooted to form plantlets. Polyploidy was induced when embryonic calli were placed in liquid MS medium containing 0.5% colchicine for 4 days, followed by culturing in solid medium to induce differentiation. Polyploidy was identified by the number of chromosomes and the size of plantlet stomata. The tetraploid plantlets produced larger root tubers than the diploid plantlets.
The aim of the study was to investigate the changes in the essential oil constituents of coriander and caraway when treated with UHP and/or elevated temperatures in a helium atmosphere. The UHP and/or heat treatment was conducted for 30 mins at 800 MPa, the temperature range was 60-121°C. The changes in the volatile oil content did not exceed 5% in all the treatment conditions. The pressure and temperature processing altered the composition of the essential oils of spices, which was examined using the GC-MS method. The most important sensory compounds, namely linalool in coriander oil and carvone in caraway oil, were not essentially changed after the processing. The final oil composition was different in the pressurised and not pressurised samples heated at the same temperature.
 Pro-inflammatory cytokines participate in the induction of ischemic stroke. So far, their participation in the cerebral ischemia was proven for the tumor necrosis factor TNF-α, interleukin-1 (IL-1), and interleukin-6 (IL-6). The release of the pro-inflammatory cytokines into the extracellular space causes the enlargement of the brain damage region, and consequently increases the neurological deficit and negatively affects the survival rate prognoses. That is confirmed by the increased concentration of pro-inflammatory cytokines in blood and the cerebrospinal fluid of patients with brain stroke, as well as by the research on the induced/experimental cerebral ischemia in animals. The pro-inflammatory cytokines participate in the migration of the reactive T lymphocytes to the regions of brain ischemia where they enhance the nerve tissue damage by down-regulation of microcirculation, induce the pro-thrombotic processes and release other neurotoxic cytokines. Also, in the early stage of cerebral ischemia, cytokines activate the axis hypothalamus-pituitary gland-adrenal cortex and increase the cortisol concentration in blood, what results in the decreased resistance to infectious diseases. Administration of the inhibitor of the interleukin-1 receptor (IL-1Ra) inhibits the inflammatory processes in the region of brain ischemia, and subsequently improves the prognosis for the size of the neurological deficit and the survival rate, as well as resistance to infectious diseases.
Altered tissue water homeostasis may contribute to edema formation during various stresses including bacterial infection. We observed induction of aquaporin-1 (AQP1) during Staphylococcus aureus infection of cultured cells indicating a potential mechanism underlying altered water homeostasis during infection. To investigate mechanisms of AQP1 induction, we examined the effects of the S. aureus alpha-hemolysin on AQP1 abundance in Balb/c fibroblasts. Fibroblasts incubated with 30 microg/ml hemolysin exhibited a 5-10 fold increase in AQP1 protein within 4-6 hours of exposure. The use of multiple signaling cascade inhibitors failed to affect hemolysin-mediated accumulation of AQP1. However, immunoprecipitation revealed an initial accumulation of ubiquitinated AQP1 followed by a decrease to baseline levels after 4 hours. Immunofluorescence indicated that following hemolysin exposure, AQP1 was no longer on the plasma membrane, but was found in a population of submembrane vacuoles. AQP1 redistribution was further indicated by surface biotinylation experiments suggesting diminished AQP1 abundance on the plasma membrane as well as redistribution out of lipid raft fractions. Live cell confocal microscopy revealed that the pattern of cell volume change observed following hemolysin exposure was altered in cells in which AQP1 was silenced. We conclude that alpha-toxin alters proteasomal processing and leads to intracellular accumulation of AQP1, which may likely contribute to disrupted cell volume homeostasis in infection.
The aim of this study was to evaluate midazolam as an intravenous induction agent for inhalation anaesthesia in the routine castration of dogs. Investigations concerned the dose required for induction as well as its effects on the dog’s general condition, arterial blood gas and acid-base balance. A total of 24 male dogs of various breeds were studied, ranging in age from 1 to 11 years and in weight from 5 to 27 kg. Dogs were recruited at the Department and Clinics of Animal Surgery, University of Life Sciences in Lublin, Poland. The dogs were premedicated intramuscularly with xylazine and atropine sulphate at dose rates of 2 mg/kg and 0.05 mg/kg respectively. Twenty minutes after premedication, midazolam was administered by intravenous infusion. Intravenous midazolam proved useful as an induction agent for inhalation anaesthesia. The dose used was dependent on the animal’s reaction. The induction of anaesthesia with midazolam was successful and enabled endotracheal intubation and inhalation anaesthesia with a halothane-oxygen mixture. The application of midazolam with halothane, however, led to transitory disturbances in systemic acid-base balance due to gas exchange abnormalities. The median effective dose of midazolam for the induction of anaesthesia was 0.46 mg/kg i.v. Postoperatively, a full recovery of consciousness and motor functions was rapidly achieved in all dogs. Further studies on midazolam as an intravenous induction agent for inhalation anaesthesia in the dog are warranted.
In this study, we investigated apoptosis induced in human trisomic and diabetic fibroblasts by daunorubicin (DNR) and its derivative, idarubicin (IDA). The cells were incubated with DNR or IDA for 2 h and then cultured in a drug-free medium for a further 2–48 h. The apoptosis in the cultured cell lines was assessed by biochemical analysis. We found that both drugs induced a timedependent loss of mitochondrial membrane potential, and a significant increase in intracellular calcium and caspase-3 activity. Mitochondrial polarization and changes in the level of intracellular calcium were observed during the first 2–6 h after drug treatment. Caspase-3 activation occurred in the late stages of the apoptotic pathway. Our findings also demonstrated that idarubicin was more cytotoxic and more effective than daunorubicin in inducing apoptosis in trisomic and diabetic fibroblasts.
The regeneration of callus was conducted on of Norway spruce (Picea abies (L.) Karst.) cotyledons from 5 to 19 days old seedlings. The best results (55% on average) were obtained from 5-days old seedlings. The highest percent of regeneration was ascertained on the 1/2 SH medium (on average for all ages 49.17%). The best medium for 5-days old seedlings turned out to be the 1/2 LP (77,50%), but the regeneration ability of cotyledons taken from older seedlings declined rapidly in that medium. On a medium with the concentration of both micro- and macroelements reduced to 50% of the fall level the average regeneration rate was 41.50%, while on a medium with full concentration of nutrients the regeneration amounted only to 25 75%. The best growth of callus after 6 weeks of cultivation was found on cotyledons taken from 5-days old seedlings on the 1/2 LM, MS arid 1/2 LP medium (the diameter of callus equal to 2.95, 2.86 and 2.21 mm respectively). Callus growing on medium with lower concentration of nutrients after 6 weeks of cultivation gave larger callus than that on medium with a full nutrient concentration {average diameters 1.86 mm and 1.52 mm, respectively).
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