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The cardio-vascular reactions after i.m. application of 0.4 mg/kg of TA (imipramine, amitryptyline and nortryptyline) were compared in normotonics and patients suffering from essential hypertonia. It was found, that systolic blood pressure decreased significantly after the drugs only in hypertonic patients, whereas diastolic blood pressure fall was marked more in the normotonic group. In both groups, no apparent changes in heart action were noticed after the drugs. The TA caused a stronger increase of urine excretion of NE, E, VMA and NMN and MN in hypertonics than in normotonics.  相似文献   
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The influence of water extract of Uncaria tomentosa (Willd.) DC bark on the meristematic cells of the root tips of Allium cepa L., e.g. cells of Allium Test, was investigated. The experiment was carried out in two variants: (1) continuous incubation at different concentrations (2, 4, 8 and 16 mg/ml) of the extract for 3, 6, 12, 24, 48 and 72h; and (2) 24-h incubation in three concentrations of the extract (4, 8 or 16 mg/ml), followed by post-incubation in distilled water for 3, 6, 12, 24 and 48h. During the continuous incubation, the mitotic activity was reduced (2 and 4 mg/ml) or totally inhibited (8 and 16 mg/ml), depending on the concentration of the extract. All the concentrations resulted in gradual reduction of the mitotic activity. In the concentration of 2 mg/ml, the mitotic activity reached its lowest value after 12h (2 mg/ml) and after 24h in 4 mg/ml, followed by spontaneous intensification of divisions during further incubation. Instead, in higher concentrations of the extracts (8 and 16 mg/ml), the mitotic activity was totally inhibited within 24h and did not resume even after 72h. Incubation caused changes in the phase index, mainly as an increase in the number of prophases. After 24h of incubation, in all phases, condensation and contraction of chromosomes were observed. During post-incubation, divisions resumed in all concentrations, reaching even higher values than the control. Cytometric analysis showed that the extract caused inhibition of the cell cycle at the border between gap(2) and beginning of mitosis (G(2)/M).  相似文献   
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The photooxidation of polystyrene films sensitized by anthracene was investigated. The quantum yield of singlet oxygen generation in the polystyrene-anthracene system, irradiated with light at λ = 365 nm in the presence of oxygen was determined. A kinetic scheme of the photophysical and photochemical processes in the system was proposed and the rate constant of anthracene dimer formation in polystyrene was estimated.  相似文献   
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The experiments presented in this paper aimed to investigate whether estrogen level changes in oviariectomized rats (OVX) may lead to depression and memory disorders, and whether the effects of such changes may be reversible following administration of a new antidepressant, venlafaxine (CAS 9930-78-4, VEN, Efectin). The Porsolt forced swimming test and Morris water maze test were carried out on female Wistar rats after ovariectomy and in sham-ovariectomized rats. VEN 20 mg/kg was administered orally 30 min before the tests for the period of 14 days. Estradiol (17beta-estradiol benzoate, CAS 50-28-2, E2) administration (5 microg E2/0.2 ml sesame oil s.c.) was started 24 h after ovariectomy and was continued for 14 days--each dose was administered 180 min before the test. In the immobility test, which reflects antidepressant drug activity, it was found that VEN shortened immobility time (IT) after the 1st, 7th and 14th administration (days 1, 7, 14, respectively) in ovariectomized rats, whereas in the control group (sham-ovariectomized rats) VEN exerted antidepressant action only after single administration (day 1) and after 7 days of administration. E2 significantly reduced immobility behaviour both after single and chronic treatment in ovariectomized rats. After joint administration of VEN and E2 potentiation of the antidepressant activity of VEN could be observed in both groups except for concurrent administration of VEN and E2 after 14 days in sham-ovariectomized rats. VEN improved the spatial memory in the Morris water maze test, whereas E2 did not affect the memory of the tested animals. Joint administration of VEN and E2 maintained the memory improving effect induced by VEN. The regulatory role of the steroid hormone and the new antidepressant drug (VEN) in antidepressant activity and memory function could be related to the interactions between noradrenergic and serotoninergic systems.  相似文献   
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Recent advances in molecular cytogenetics enable identification of small chromosomal aberrations that are undetectable by routine chromosome banding in 5-20% of patients with mental retardation/developmental delay (MR/DD) and dysmorphism. The aim of this study was to compare the clinical usefulness of two molecular cytogenetic techniques, metaphase high-resolution comparative genomic hybridization (HR-CGH) and targeted array CGH, also known as Chromosomal Microarray Analysis (CMA). A total of 116 patients with unexplained mild to severe MR and other features suggestive of a chromosomal abnormality with apparently normal or balanced karyotypes were analyzed using HR-CGH (43 patients) and/or CMA (91 patients). Metaphase HR-CGH detected seven interstitial deletions (16.3%). Rare deletions of chromosomes 16 (16p11.2p12.1) and 8 (8q21.11q21.2) were identified. Targeted CMA revealed copy-number changes in 19 of 91 patients (20.8%), among which 11 (11.8%) were clinically relevant, 6 (6.5%) were interpreted as polymorphic variants and 2 (2.1%) were of uncertain significance. The changes varied in size from 0.5 to 12.9 Mb. In summary, our results show that metaphase HR-CGH and array CGH techniques have become important components in cytogenetic diagnostics, particularly for detecting cryptic constitutional chromosome imbalances in patients with MR, in whom the underlying genetic defect is unknown. Additionally, application of both methods together increased the detection rates of genomic imbalances in the tested groups.  相似文献   
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