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951.
E Beck R Sommer E A Auerswald C Kurz B Zink G Osterburg H Schaller K Sugimoto H Sugisaki T Okamoto M Takanami 《Nucleic acids research》1978,5(12):4495-4503
The sequence of the 6,408 nucleotides of bacteriophage fd DNA has been determined. This allows to deduce the exact organisation of the filamentous phage genome and provides easy access to DNA segments of known structure and function. 相似文献
952.
953.
Szczepanek-Parulska E Zybek A Biczysko M Majewski P Ruchała M 《Endokrynologia Polska》2012,63(2):138-142
Subacute granulomatous thyroiditis (SAT), also known as de Quervain's thyroiditis or painful subacute thyroiditis, is the commonest thyroid condition responsible for neck tenderness. Other causes of pain in the thyroid gland should be taken into consideration during differential diagnosis, especially when a patient presents with misleading or equivocal signs and symptoms. We report the case of a 39 year-old woman diagnosed as having SAT whose clinical, biochemical and radiological presentation varied significantly from the common SAT manifestation. A tentative diagnosis of SAT was made based on the presented symptoms, ultrasonography and fine-needle biopsy results. However, biochemical analysis suggested neither inflammatory process nor the presence of thyrotoxicosis. Moreover, technetium scan of the thyroid revealed normal uptake of the isotope and there was neither clinical nor ultasonographic response for corticosteroids. The patient's symptoms, despite being prescribed typical treatment, gradually deteriorated and the pain became increasingly debilitating. Eventually, the patient underwent total thyroidectomy. As a result, she has become free of symptoms, but the macroscopic picture of thyroid gland, noted during the operation, gave a suspicion of neoplastic process. Nevertheless, histological study of flow samples confirmed the tentative diagnosis of de Quervain's thyroiditis, despite all previous findings that were not suggestive of it. This report confirms the likelihood that SAT can present atypically. Additionally, it indicates that surgical treatment may be considered in patients with severe, debilitating, persistent thyroid gland pain connected with SAT clinical course. 相似文献
954.
The aim of this study was to look at basic endocrinological disorders in chronic kidney disease, acquainting endocrinologists with information about the definition and classification of kidney diseases and basic metabolic disorders in uraemia. Secondary hyperparathyroidism, insulin resistance and hyperinsulinism, growth hormone disorders and the possibility of growth hormone treatment, the reasons for and the consequences of hyperprolactinaemia are presented in a practical way. Thyroid hormones management, a problem which requires further study, is portrayed extensively. Hypothalamic-pituitary-adrenal axis disorders are equally complex and not yet fully examined. We have largely concentrated on the practical aspects of diagnostics of the presented disorders. 相似文献
955.
Aleksandra Szczepkowska Barbara W?sowska Przemys?aw D. Gilun Christine Lagaraine Vincent Robert Laurence Dufourny Jean-Claude Thiéry Janina Skipor 《Cell and tissue research》2012,350(1):157-166
Vascular endothelial growth factor (VEGF-A) plays an important role in maintaining cerebrospinal fluid (CSF) homeostasis and the function of the choroid plexuses (CPs). The objective of the study was to determine the expression of vascular endothelial growth factor (VEGF-A), tyrosine kinase receptors Flt-1 and KDR and KDR co-receptor neuropilin 1 (NRP-1) in ovine CPs during different photoperiods. CPs were collected from the lateral brain ventricles from ovariectomized, estradiol-treated ewes during long day (LD; 16L:8D, n?=?5) and short day (SD; 8L:16D, n?=?5) photoperiods. We analyzed mRNA expression levels of two VEGF-A isoforms, VEGF-A 120 and VEGF-A 164 and our results indicate that VEGF-A 164 was the predominant isoform. Expression levels of VEGF-A and Flt-1 were similar during the SD and LD photoperiods. There were significant increases in KDR mRNA and protein expression (p?<?0.05) and NRP-1 mRNA expression (p?<?0.05) during SD. These data show that expression of KDR and its co-receptor NRP-1 are up-regulated by short photoperiod and that this effect is not dependent on ovarian steroids. Our results suggest that the VEGF-A-system may be involved in photoperiodic plasticity of CP capillaries and may therefore be responsible for photoperiodic changes in the CSF turnover rate in ewes. 相似文献
956.
We investigated interactions of human isolates of Acinetobacter calcoaceticus-baumannii complex strains with epithelial cells. The results showed that bacterial contact with the cells as well as adhesion and invasion were required for induction of cytotoxicity. The infected cells revealed hallmarks of apoptosis characterized by cell shrinking, condensed chromatin, and internucleosomal fragmentation of nuclear DNA. The highest apoptotic index was observed for 4 of 10 A. calcoaceticus and 4 of 7 A. baumannii strains. Moreover, we observed oncotic changes: cellular swelling and blebbing, noncondensed chromatin, and the absence of DNA fragmentation. The highest oncotic index was observed in cells infected with 6 A. calcoaceticus isolates. Cell-contact cytotoxicity and cell death were not inhibited by the pan-caspase inhibitor z-VAD-fmk. Induction of oncosis was correlated with increased invasive ability of the strains. We demonstrated that the mitochondria of infected cells undergo structural and functional alterations which can lead to cell death. Infected apoptotic and oncotic cells exhibited loss of mitochondrial transmembrane potential (ΔΨ(m)). Bacterial infection caused generation of nitric oxide and reactive oxygen species. This study indicated that Acinetobacter spp. induced strain-dependent distinct types of epithelial cell death that may contribute to the pathogenesis of bacterial infection. 相似文献
957.
In recent years, Enterococcus faecalis has emerged as an important opportunistic nosocomial pathogen capable of causing dangerous infections. Therefore, there is an urgent need to develop novel antibacterial agents to control this pathogen. Bacteriophages have very effective bactericidal activity and several advantages over other antimicrobial agents and so far, no serious or irreversible side effects of phage therapy have been described. The objective of this study was to characterize a novel virulent bacteriophage φ4D isolated from sewage. Electron microscopy revealed its resemblance to Myoviridae, with an isometric head (74 ± 4 nm) and a long contractile tail (164 ± 4 nm). The φ4D phage genome was tested using pulsed-field gel electrophoresis and estimated to be 145 ± 2 kb. It exhibited short latent period (25 min) and a relatively small burst size (36 PFU/cell). Tests were conducted on the host range, multiplicities of infection (MOI), thermal stability, digestion of DNA by restriction enzymes, and proteomic analyses of this phage. The isolated phage was capable of infecting a wide spectrum of enterococcal strains. The results of these investigations indicate that φ4D is similar to other Myoviridae bacteriophages (for example φEF24C), which have been successfully used in phagotherapy. 相似文献
958.
Dietrich-Muszalska A Malinowska J Olas B Głowacki R Bald E Wachowicz B Rabe-Jabłońska J 《Neurochemical research》2012,37(5):1057-1062
The mechanisms of oxidative stress in schizophrenic patients are not fully understood. In the present study, we investigated
the effect of elevated level of homocysteine (Hcys) on some parameters of oxidative stress, namely thiobarbituric acid reactive
substances (TBARS), an index of lipid peroxidation in plasma, the level of carbonyl groups in plasma proteins, as well as
the amount of 3-nitrotyrosine in plasma proteins isolated from schizophrenic patients. Patients hospitalised in I and II Psychiatric
Department of Medical University in Lodz, Poland were interviewed with special questionnaire (treatment, course of diseases,
dyskinesis and other EPS). According to DSM-IV criteria all patients had diagnosis of paranoid type. They were treated with
antipsychotic drugs (clozapine, risperidone, olanzapine). Mean time of schizophrenia duration was about 5 years. High-performance
liquid chromatography was used to analyse the total level of homocysteine in plasma. Levels of carbonyl groups and 3-nitrotyrosine
residues in plasma proteins were measured by ELISA and a competition ELISA, respectively. The lipid peroxidation in plasma
was measured by the level of TBARS. Our results showed that in schizophrenic patients the amount of homocysteine in plasma
was higher in comparison with the control group. We also observed a statistically increased level of biomarkers of oxidative/nitrative
stress such as carbonyl groups or 3-nitrotyrosine in plasma proteins from schizophrenic patients. Moreover, our experiments
indicate that the correlation between the increased amount of homocysteine and the oxidative stress exists. Considering the
data presented in this study, we suggest that the elevated Hcys in schizophrenic patients may stimulate the oxidative stress. 相似文献
959.
Katarzyna Bzdęga Agnieszka Janiak Sabina Tarłowska Marzena Kurowska Barbara Tokarska-Guzik Iwona Szarejko 《Flora》2012
Recently much attention has been paid to genetic aspects of invasive success in Japanese knotweed s.l. One hypothesis to explain the invasive spread of these species is a multiple introduction, which leads to a higher level of genetic diversity in the invaded range. Fallopia japonica is considered to be genetically uniform in Europe, introduced as a single female clone. However, there is some evidence suggesting that invasion history and dynamics differ between Western and Central-Eastern Europe. We used AFLP markers to characterize genetic diversity of three Fallopia taxa that occur in Poland: F. japonica, F. sachalinensis and their hybrid Fallopia × bohemica, growing in so-called ‘homogeneous’ populations, consisting of one taxon and ‘heterogeneous’ populations, composed of the three taxa cohabiting together. No polymorphism, resp. an insignificantly low variability was observed in the ‘homogeneous’ populations. In the ‘heterogeneous’ stands polymorphism was detected within each taxa, with one exception that concerns individuals of F. sachalinensis from a riparian habitat. The highest level of polymorphism was found among individuals of F. × bohemica. The most striking result of our study is the observation of polymorphism between individuals of F. japonica. The AFLP data also showed that F. × bohemica is most diverse when occurring in a heterogeneous configuration with F. japonica and F. sachalinensis in the same habitat. Our results are the first evidence of genetic diversity in F. japonica populations in Central Europe and can implicate the possibility of its multiple introduction in this region or the existence of sexual reproduction of this species. 相似文献
960.
Analysis of variation at 10 polymorphic isoenzyme loci in 51 European populations of Pinus sylvestris both from its main continuous range and from isolated, marginal populations out of the continuous range, revealed differences in genetic structure. The highest genetic richness, measured as mean number of alleles per locus, was recorded for populations from the Iberian Peninsula, followed by those from Scotland and the Balkans. Marginal, isolated populations were characterized by much greater interpopulation variation than populations from the continuous range of the species. The highest mean observed heterozygosity was recorded for the Iberian populations. The highest gene flow was observed among populations in the continuous range of the species. The populations could be classified into five groups based on genetic similarities. Populations from the continuous range formed one group, those from Spain two groups, pines from Scotland one group and those from the Balkans one group. One population from Scotland was found to be most distinct from the other Scottish pines and was found to be grouped with the Balkan populations. The occurrence and frequencies of rare alleles in the populations showed a characteristic pattern, suggesting that populations from the Iberian Peninsula probably did not participate in the colonization of Europe by Pinus sylvestris after the last glaciation. In contrast, the migration of populations from the Balkan refugium into Central and Western Europe had a significant effect on the contemporary gene pools of populations of Pinus sylvestris in its continuous range. 相似文献