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51.
Effects of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) on the development and expression of male sex were tested using the model of the three-zonal structure of 12-day-old (15-celled) Anemia phyllitidis gametophyte. ACC at 10 M concentration enhanced the number of antheridia induced by gibberellic acid. Cytomorphological measurements showed that this effect was limited to only the antheridial region of gametophytes and depended on transverse expansion of antheridial mother cells. Time-course cytophotometrical measurements showed that this promotive effect of ACC was preceded by reorganization of nuclear chromatin and induction of DNA synthesis in nuclei in the antheridial region cells of fern gametophytes.Abbreviations ACC: 1-Aminocyclopropane-1-carboxylic acid. - CPA: Cell profile area. - GA: Gibberellin. - GA3: Gibberellic acid. - NPA: Nuclear profile area. - TE: Tris-EDTA buffer.Communicated by D. Bartels  相似文献   
52.
We investigated whether amyloid--peptide (A1–42) has an effect on the elevations of the intracellular concentration of Ca2+ ions ([Ca2+]i) induced by depolarizations of NG108-15 cells and on related Ca2+ channels. A1–42 (10-1000 nM) had no immediate effect on depolarization-induced [Ca2+]i elevations. [Ca2+]i increases were slightly diminished in cells grown in the presence of 100 or 1000 nM A1–42. Nifedipine (1 M) reduced these elevations equally in cells grown in the absence or presence of A1–42. In contrast, the ability of -conotoxin GVIA to diminish the depolarization-induced [Ca2+]i responses became lost in cells grown in the presence of 100 nM A1–42. This indicates that the influx of calcium through the N-type Ca2+ channels was compromised by the chronic exposure of cells to a submicromolar concentration of A1–42, presumably because of impairement of their function or diminished expression. This may be important in the pathogeny of Alzheimer's dementia in view of the pivotal role of N-type Ca2+ channels in neurotransmitter release.  相似文献   
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54.
SUMMARY 1. In vivo 1H and 31P magnetic resonance spectroscopy techniques were applied to reveal biochemical changes in the rat brain caused by prolonged ethanol consumption.2. Three models of ethanol intoxication were used.3. 1H MRS showed a significant decrease in the concentration of myo-inositol in the brain of rats fed with 20% ethanol for 8 weeks. This change is consistent with perturbances in astrocytes. On the other hand, N-acetyl aspartate and choline content did not differ from controls.4. 31P MRS did not reveal any significant changes in the high-energy phosphates or intracellular free Mg2+ content in the brain of rats after 14 weeks of 20% ethanol drinking. The intracellular pH was diminished.5. By means of a 31P saturation transfer technique, a significant decrease was observed for the pseudo first-order rate constant k for of the creatine kinase reaction in the brain of rats administered 30% ethanol for 3 weeks using a gastric tube.6. The 1H MRS results may indicate that myo-inositol loss, reflecting a disorder in astrocytes, might be one of the first changes associated with alcoholism, which could be detected in the brain by means of in vivo 1H MRS.7. The results from 31P MRS experiments suggest that alcoholism is associated with decreased brain energy metabolism.8. 31P saturation transfer, which provides insight into the turnover of high-energy phosphates, could be a more suitable technique for studying the brain energetics in chronic pathological states than conventional 31P MRS.  相似文献   
55.
In diagnosis of CMV infection various laboratory methods are used. The methods based on detection of viral nucleic acids have been introduced routinely in many laboratories. The aim of this study was to compare nucleic acid hybridisation method and various variants of PCR methods with respect to their ability to detect CMV DNA. The studied material comprised 60 blood samples from 19 patients including 13 renal transplant recipients and 6 with acute leukaemia. The samples were subjected to hybridisation (Murex Hybrid Capture System CMV DNA) and PCR carried out in 3 variants: with one pair of primers (single PCR), nested PCR and Digene SHARP System with detection of PCR product using a genetic probe in ELISA system. The sensitivity of the variants ranged from 10(0) particles of viral DNA in nested PCR to 10(2) in single PCR. The producer claimed the sensitivity of the hybridisation test to be 3 x 10(5) and it seems to be sufficient for detection of CMV infection. The obtained results show that sensitivity of hybridisation was comparable to that of single PCR and the possibility of obtaining quantitative results makes it superior, on efficacy of antiviral therapy, especially in monitoring CMV infection in immunossuppressed patients and in following the efficacy of antiviral treatment.  相似文献   
56.
The study was aimed at assessment of the sensitivity of methicillin-resistant coagulase-negative staphylococci isolated from clinical material in 1997/1998 to selected chemotherapeutic agents. The investigated material comprised 96 methicillin-resistant coagulase-negative staphylococci from hospital and ambulatory infections isolated during the period from April 1997 to May 1998. Species affiliation was determined by classical identification methods and commercial diagnostic tests for identification of staphylococci. Methicillin resistance was determined by agar disk-diffusion method and screening. Sensitivity to chemotherapeutics was determined by agar disk-diffusion method and agar dilution methods. All the investigated strains were sensitive to nitrofurantoin, furazolidone and vancomycin. To teicoplanin--the second glycopeptide antibiotic--84% strains were sensitive, whereas the percentages of resistant and moderately sensitive strains amounted to 5.2% and 10.4%, respectively. 85% and 82% of coagulase-negative staphylococcal strains were sensitive to fusidic acid and mupirocin. Considerable differences were noted with respect to sensitivity to aminoglycoside group antibiotics. About 35% of strains were sensitive to gentamicin, and 90% sensitive to netilmicin. Ca. 40% of coagulase-negative staphylococci were resistant both to cotrimoxazole and trimethoprim, which, in view of 98% resistance to the second component of cotrimoxazole, may be associated with the activity of only one of the components of the drug--trimethoprim.  相似文献   
57.
创伤性脑损伤是一种高致死率的疾病,严重危害人类生命健康。肠脑轴是大脑和胃肠道系统之间主要的双向通讯途径。近年来,创伤性脑损伤与肠道菌群的相互作用关系逐渐被揭示。肠道菌群通过肠脑轴参与了创伤性脑损伤后急性病理损伤的调节过程并发挥重要作用。本文综述了创伤性脑损伤的发生、对人类健康的巨大影响,肠脑轴的含义及其在颅脑损伤中的病理调节机制,并在此基础上提出可能的治疗手段,包括粪便微生物菌群移植、使用益生菌、刺激迷走神经、摄入多酚类物质以及靶向免疫调节策略,以期为临床治疗创伤性脑损伤提供新的思路。  相似文献   
58.
Meningeal involvement was diagnosed in a child with IVB degree Hodgkin's disease following three alternatives cures with MVPP/B-DOPA. Irradiation of the skull with alternative intrathecal injections of drugs were applied. The treatment was completed 16 months after the diagnosis of meningeal involvement. No symptoms are observed.  相似文献   
59.
BackgroundThe second wave of avian influenza H7N9 virus outbreak in humans spread to the Guangdong province of China by August of 2013 and this virus is now endemic in poultry in this region.MethodsFive patients with H7N9 virus infection admitted to our hospital during August 2013 to February 2014 were intensively investigated. Viral load in the respiratory tract was determined by quantitative polymerase chain reaction (Q-PCR) and cytokine levels were measured by bead-based flow cytometery.ResultsFour patients survived and one died. Viral load in different clinical specimens was correlated with cytokine levels in plasma and broncho-alveolar fluid (BALF), therapeutic modalities used and clinical outcome. Intravenous zanamivir appeared to be better than peramivir as salvage therapy in patients who failed to respond to oseltamivir. Higher and more prolonged viral load was found in the sputum or endotracheal aspirates compared to throat swabs. Upregulation of proinflammatory cytokines IP-10, MCP-1, MIG, MIP-1α/β, IL-1β and IL-8 was found in the plasma and BALF samples. The levels of cytokines in the plasma and viral load were correlated with disease severity. Reactivation of herpes simplex virus type 1(HSV-1) was found in three out of five patients (60%).ConclusionExpectorated sputum or endotracheal aspirate specimens are preferable to throat swabs for detecting and monitoring H7N9 virus. Severity of the disease was correlated to the viral load in the respiratory tract as well as the extents of cytokinemia. Reactivation of HSV-1 may contribute to clinical outcome.  相似文献   
60.
BackgroundIn Senegal, with the variable routine vaccination coverage, the risk for illness and death from measles still exists as evidenced by the measles epidemic episode in 2009. Since 2002 a laboratory-based surveillance system of measles was established by the Ministry of Health and the Institut Pasteur de Dakar. The present study analysed the data collected over the 10 years inclusive between 2004-2013 in order to define a measles epidemiological profile in Senegal, and we carried out a phylogenetic analysis of measles virus circulating in Senegal over the period 2009-2012.ConclusionImprovements in the measles surveillance in Senegal are required and the introduction of oral fluid and FTA cards as an alternative to transportation of sera should be investigated to improve surveillance. The introduction of a national vaccine database including number of doses of measles-containing vaccine will greatly improve efforts to interrupt and ultimately eliminate measles virus transmission in Senegal.  相似文献   
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