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41.
Isolated nephrons from premetamorphic lamprey larvae and adult animals were obtained using microdissection and kidney collagenase treatment methods. Significant differences in the architectonics of kidney tubules were found in larvae as compared with adults. The position of larval kidney was cranial while that in adult lampreys was caudal. The absence of nephron loop was noted in larval kidney. Distal and proximal tubules were shifted one from another in mediolateral direction. Distal tubule was significantly larger than proximal one. Mesonephric duct was located laterally near the glomus. Kidney tubules morphogenesis and nephron population number increase was observed at premetamorphic stage of larval kidney development.  相似文献   
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The action of duck egg drop syndrome 1976 (EDS-76) adenovirus on model bilayer lipid membranes (BLM) has been investigated on planar egg phosphatidylcholine membranes and small unilamellar vesicles. It was found that the adenovirus formed channels in planar BLM in a pH-dependent manner. The addition of EDS-76 to planar BLM at pH 5 induced voltage-independent channel activity of about 60 pS conductivity after a lag phase. At pH 3, EDS-76 induced irregular spikes of current across the planar BLM which disappeared after several minutes. The adenovirus also was able to induce pH-dependent leakage of calcein-loaded liposomes. EDS-76 did not induce channel activity in planar BLM or liposome leakage at neutral pH.  相似文献   
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The aim of this double-blind, placebo-controlled, comparative study was to differentiate the clinical efficacy and tolerability of human leukocyte interferon-alpha incorporated (2 x 10(6) IU/g) in a hydrophilic cream and in a gel to heal males afflicted with first episodes of genital herpes. Patients (n = 60), aged 18-40 years (mean 23.2) with culture-confirmed diagnosis of herpes genitalis were randomized to three parallel groups. Each patient was allocated a precoded 40-g tube, containing either preparation or placebo. Cream or gel was applied three times daily for 5 consecutive days. The duration of the active treatment was two weeks. Patients were examined after 48 hours in initial treatment, and thereafter two times a week. A reepithelialized lesion with some residual erythema was recorded as healed. The study demonstrated that patients treated with leukocyte interferon-alpha cream had both significantly shorter mean duration of lesions than gel and placebo recipients (5.3 days vs. 8 days, 13 days respectively; p < 0.001) and a higher number of healed patients (80% vs. 55%, 20% respectively; p < 0.001). Of the 60 patients, 49 (82%) complained of no drug-related side effects. Eleven patients predominantly in the cream/gel groups reported non-objective transitory increase in their body temperature (> 38 degrees C) with moderate headache, malaise and myalgia. The study was followed-up for 24 months after the first day of the treatment, and out of 31/60 cured patients, 4 had a relapse after 18 months. In conclusion the study affirmed that human leukocyte interferon-alpha (2 x 10(6) IU/g) in a hydrophilic cream is more efficacious than its incorporation in gel or placebo, thus suggesting that leukocyte interferon-alpha in a hydrophilic cream, with a profile of non-objective mild to moderate drug-induced indications, may be considered an alternative and effective treatment modality to cure male patients afflicted with first episodes of genital herpes.  相似文献   
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To describe electrical phenomena observed in growth of Neurospora crassa hyphae, a theoretical model was developed considering the hypha as a one-dimensional electric cable with non-uniform longitudinal distribution of current sources reflecting the activity of proton pumps. A profile of the density of the pump current along the hypha is proposed, at which the results of simulation quantitatively coincide with the results of physiological experiments. The model values of energy coupling in the growth zones were estimated. The experimental dependence of the elongation rate of regenerating apical hypha fragments on their lengths was determined. Based on the comparison of these experimental results with the results of analysis of the model, the contribution of the axial metabolite transport, from the distal parts of the hypha to the apical part, to the dynamics of the apical cell growth was estimated. The possibility of evaluating the intensity of high-molecular-weight syntheses and/or accumulation of substances in granules was demonstrated. The growth rate of the regenerating hypha fragments was shown to correlate with the electric current flowing into the apical fragment 0.2-mm in length.  相似文献   
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It has been established that hippocampus, enthorhinal cortex, amygdala and substantia nigra (pars reticulata) lesions before head injury lead to a decrease of kainic acid-induced behavioral and electrographic seizure expressions. It can be concluded that after head injury the activation of limbic structures excitability due to excitation of "inputs" to these formations takes place. The obtained data indicate the significant role of nucleus caudatus in activation of posttraumatic brain excitatory mechanisms.  相似文献   
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Parental illness can have a profound impact on family relationships and children's behaviour. The amount and nature of communication between parents and children about the illness can play an important role, both positively and negatively, in mediating the outcomes. When children have a disability, families can be reluctant to communicate with them about family difficulties. They are often concerned about the impact that parental unavailability may have on their child's life. This paper reports on three families in which the mother was diagnosed with breast cancer and one child in the family had a disability. The extent and specific characteristics of their communication about the maternal illness with their children, behavioural changes in the children, explanations of communication strategies and attributions of behavioural changes are described. Family coping strategies are examined with reference to Lazarus's process model of stress and coping and the use of either problem-focused or emotion-focused strategies. Implications for possible clinical interventions are proposed. In particular it is suggested that families be offered consultation about: what children might understand; ways in which to communicate effectively; and strategies for coping with the long-term implications of serious parental illness.  相似文献   
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The majority of early-onset familial Alzheimer's disease (FAD) is associated with mutations in the presenilin-1 (PS1) gene. We describe a novel Polish PS1 mutation of Pro117Leu, associated with the earliest average age of onset and death so far reported in a PS-linked, FAD kindred. Human kidney 293 and mouse neuroblastoma N2a cells were stably transfected with wild-type and PS1 P117L. There was a significant increase in the amyloid beta42/40 ratio in the N2a P117L PS1 transfected cells compared with N2a transfected with wild-type PS1. What role PS has in the pathogenesis of AD remains to be determined, however, the severity of the clinical picture associated with this PS1 mutation stresses the importance of presenilin.  相似文献   
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