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Despite extensive forest destruction in the Middle Ages and later intensive commercial forest management, remnants of virgin forests remained spared in some Central, Eastern and South-Eastern European countries. These virgin forests are the last examples of original forests in this part of Europe. That is why their protection becomes an important issue of current European forestry and nature protection policy. But the knowledge about the location and the area of virgin forests in these countries is incomplete up till now. This article has the prime goal to present a conceptual framework what virgin forests might be (“A conceptual framework for defining of virgin forests” section). Based on this framework, a working methodology has been tested in Bulgaria and Romania (“Results of the two national projects in Romania and in Bulgaria” section and further). For this reason two projects have been carried out by the Royal Dutch Society of Nature Conservation (KNNV) in close co-operation with the Forestry Institutes in Romania and in Bulgaria. The results of these projects are described in general terms and further analysis in the future is necessary to describe specific features like forest structure and spatial heterogeneity of these forests. Based on the results of the inventory, principles of sustainable protection and management of the mapped virgin forests were defined and described in the research reports. The usefulness of the inventory became evident already during the EU pre-accession period of both countries while preparing the NATURA 2000 network. The remaining virgin forests of temperate Europe are an inexhaustible source of ecological information about biodiversity, structure, natural processes and overall functioning of undisturbed forest ecosystems. Their research will reveal information which can be used for ecological restoration of man-made forests which are degraded through intensive forestry practices over the last centuries. The last virgin forests of temperate Europe represent an irreplaceable part of the natural capital of Europe and are worth to be protected by law. Their last remnants in South-Eastern and Eastern Europe are endangered by commercial activities. A full inventory of remaining virgin forests in all countries of temperate Europe is a matter of highest urgency. A representative selection of virgin forest sites should be declared by UNESCO as World Heritage Sites.  相似文献   
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To date, research has led to the invention of multiple genes and their single nucleotide polymorphisms (SNPs) and environmental factors that influence the prostate cancer (PCa) pathogenesis. Therefore, the genes involved in these pathways are candidates for PCa predisposition. It is thought that polymorphisms of 5alpha-reductase II (SRD5A2) and 17 hydroxylase (CYP17) genes are likely to increase susceptibility. The aim of this study was to investigate the risk association of SRD5A2 and CYP17 gene polymorphisms in the development and progression of PCa in the Turkish population. In this study, 100 PCa patients and 105 healthy controls were studied. SRD5A2 and CYP17 gene polymorphisms were determined by real-time PCR and polymerase chain reaction-restriction length polymorphisms (PCR-RFLP) techniques. First, the AT and TT genotypes of SRD5A2 gene at codon 49 were not observed. Second, there was no significant association between the polymorphisms at codon 89 and the risk of PCa. Third, in the CYP17 gene, the A1A1 genotype is more common (46%) in cases than controls (32.4%). The odds ratios (ORs) of the A1A1 genotype was found at 1.69 (95% confidence interval [CI], 0.77-3.74) compare with the A2A2 genotype. Genotyping results of the SRD5A2 and CYP17 genes were also analyzed in relation to prostate-specific antigen (PSA) levels, Gleason score (GS), and tumor stage, but no statistically significant difference was observed (P > 0.05). Finally, we conclude that there was no evidence of an association between CYP17 (P = 0.134) and SRD5A2 (P = 0.784) polymorphism and PCa risk in the Turkish population.  相似文献   
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As raloxifene is a mixed estrogen receptor agonist and antagonist, it exerts different effects on apoptosis in different tissues. In this study, we aimed to evaluate apoptosis in the peripheral lymphocytes of postmenopausal women treated with raloxifene and compare it with untreated control subjects. In this way, we expected to deduce some results about the effect of raloxifene on the immune system and to serve as a guide for future studies on this newly proposed effect of a well-known agent. Twenty osteoporotic postmenopausal women treated with raloxifene for 12 months were included in this study. Another 20 osteoporotic postmenopausal women matched for age and postmenopausal years, but without any medication, were chosen as the control group. Apoptosis was evaluated using a morphological and DNA fragmentation assay, in the peripheral lymphocytes of these women. Our results revealed a decrease in the apoptosis percentages of the patients treated with raloxifene (14.6%) with respect to the control subjects (15.8%), but the difference was not statistically significant (p=0.467). This study indicated that raloxifene treatment had no apoptotic effect on peripheral human lymphocytes compared to controls.  相似文献   
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Protoplasma - Colchicum speciosum Steven species is a perennial stemless plant. C. speciosum is a flowering herb native to mountainous regions of northern Turkey, the Caucasus, and northern Iran....  相似文献   
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Therapeutic effect of interferon-β (IFN-β) treatment has been associated with modulation of the balance between Th1, Th17, Th2 and regulatory T (Treg) cells, whereas the impact of disease modifying drugs on Th9-immunity in multiple sclerosis (MS) has not been studied. To investigate the short-term effects of IFN-β treatment on cytokines in MS, we determined serum levels of IL-17, IL-23, IL-10, IL-4, IFN-γ, IL-9 and TGF-β in relapsing remitting MS patients before and 2 months after IFN-β treatment by ELISA. MS patients showed increased IL-17, IL-23 and IL-4 levels and decreased IL-9 levels as compared to healthy controls. IFN-β treatment only reduced IL-17 and IL-23 levels, whereas the levels of other cytokines remained unchanged. IFN-β treatment appears to exert its earliest therapeutic effect on Th17-immunity. The influence of IL-9 on MS pathogenesis needs to be further studied.  相似文献   
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Systemic dissemination of microbial pathogens permits microbes to spread from the initial site of infection to secondary target tissues and is responsible for most mortality due to bacterial infections. Dissemination is a critical stage of disease progression by the Lyme spirochaete, Borrelia burgdorferi. However, many mechanistic features of the process are not yet understood. A key step is adhesion of circulating microbes to vascular surfaces in the face of the shear forces present in flowing blood. Using real‐time microscopic imaging of the Lyme spirochaete in living mice we previously identified the first bacterial protein (B. burgdorferi BBK32) shown to mediate vascular adhesion in vivo. Vascular adhesion is also dependent on host fibronectin (Fn) and glycosaminoglycans (GAGs). In the present study, we investigated the mechanisms of BBK32‐dependent vascular adhesion in vivo. We determined that BBK32–Fn interactions (tethering) function as a molecular braking mechanism that permits the formation of more stable BBK32–GAG interactions (dragging) between circulating bacteria and vascular surfaces. Since BBK32‐like proteins are expressed in a variety of pathogens we believe that the vascular adhesion mechanisms we have deciphered here may be critical for understanding the dissemination mechanisms of other bacterial pathogens.  相似文献   
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Partial trisomy 1q including different segments of the long arm is a rare cytogenetic anomaly. Especially the cases with mosaic proximal tandem duplication of 1q included a longer fragment are very rare. Cases who have partial 1q trisomy showed large phenotypic variation due to the differences in size of the duplicated segments of 1q. The clinical phenotype of most cases is characterized by multiple congenital anomalies especially including central nervous system and developmental delay. We describe a prenatally diagnosed case with mild cerebral ventriculomegaly and karyotype with mosaic pure trisomy of chromosome 1q [(46,XX/46,XX,dup(1)(q21qter)]. Phenotypic postmortem examination showed cranial asymmetry, flat and broad nasal bridge, anteverted nostrils, hypertelorism, retrognathia, abnormal pinnae, hypoplasic thumbs, long fingers and toes, mediodorsal curvature of the 4th and 5th toes and posterior prominence of the heel was observed. Autopsy confirmed the ventriculomegaly. Postmortem chromosome preparation from skin culture, cord blood and intracardiac blood confirmed the mosaic pure trisomy of chromosome 1q.  相似文献   
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