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41.
A prospective study of 6825 labours was undertaken to determine the relation between the Apgar scores of the babies at one minute and the cardiotocograph tracing in labour. The sensitivity of an abnormal tracing was 35.2% for babies who needed intermittent positive pressure ventilation and 20.0% for babies who did not but who had Apgar scores of less than 7. The sensitivity of an abnormal tracing for all babies with an Apgar score of less than 7 was 23.2%. The positive predictive value of an abnormal tracing was 8.7% for babies who needed intermittent positive pressure ventilation and 18.7% for babies who did not but who had an Apgar score of less than 7. The positive predictive value of an abnormal tracing was 27.4% for all babies with an Apgar score of less than 7. The specificity of the tracing was 93.4% for babies with an Apgar score of 7 or over. The relatively high incidence of false positive predictions might be explained on the grounds that abnormalities in the cardiotocograph tracing are a more sensitive indicator of hypoxia than the Apgar score. False negative predictions might have been due to adverse factors other than hypoxia--for example, fetal trauma, compression of the head, infection, and analgesia in labour. These findings suggest that the current overdependence on fetal monitoring by cardiotocography alone should be examined and that other reliable indicators for non-hypoxic fetal distress should be sought.  相似文献   
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Polypropylene mesh is the most widely used material in inguinal hernia repair. Although polypropylene mesh is known as an inert material, it is experimentally proven that mesh generates a chronic inflammatory tissue reaction. The aim of the present study was to investigate the long-term effects of polypropylene mesh material used in inguinal hernia operations on testicular function, testicular nitric oxide (NO) metabolism and germ cell-specific apoptosis in rats. The study comprised 40 male rats that were randomly allocated into two groups. In group 1, the left spermatic cord was elevated and a 0.5 x 1 cm polypropylene mesh was placed behind the left inguinal spermatic cord and group 2 consisted of the sham-operated controls. Blood samples were taken at 6 months preoperatively and postoperatively after to assess luteinizing hormone (LH) and follicle stimulating hormone (FSH) levels for hormonal evaluation. Testicular NO was evaluated by the Griess method, apoptosis by a TUNEL method and inducible nitric oxide synthase (iNOS) and endothelial NOS (eNOS) expressions by immunohistochemical staining. Mild (+) eNOS expression was observed in all specimens. Mild (+) iNOS expression was only detected in ipsilateral testis of the mesh-implanted study group. Apoptotic cells were not detected in any samples. We are of the opinion that long-term polypropylene mesh implantation has no effect on testicular hormonal function and only a limited effect on nitric oxide levels and this effect is not sufficient to cause apoptosis in testis that could lead to infertility. It seems that mesh implantation is a reliable method in inguinal hernia repair; however, further work is required by more sensitive methods to fully elucidate the potential testicular damage.  相似文献   
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A new halophytic species, Scorzonera tuzgoluensis A. Duran, B. Do?an & S. Makbul sp. nov. (Asteraceae), is described and illustrated from Tuz Lake, central Anatolia, Turkey. The new species grows in salt marshes, is endemic (confined to central Anatolia) and closely related to Scorzonera parviflora Jacq. and S. elata Boiss. The diagnostic morphological characters of these similar taxa are discussed. The ecology, biogeography and conservation status of the new species are also presented. The geographic distribution of the new species and related species is mapped.  相似文献   
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Brassinosteroids (BRs) play a significant role in alleviating the negative effects of various environmental stresses and in promoting the growth and development of plants. In this study, we investigated the effects of 24-epibrassinolide (EBL) on the growth, boron (B) accumulation and activation of the antioxidant system of Arabidopsis thaliana (L.) Heynh exposed to high concentrations of boric acid (BA). A. thaliana plants were grown in a hydroponic culture, and after 4 weeks, the plants were transferred to media containing either 0.80 or 1.60 mM BA. Following BA treatment, 0.01 and 1 µM EBL was sprayed on the entire foliar region of the seedlings. B toxicity induced oxidative stress and considerably inhibited the growth of the plants. The spraying of EBL on the B-treated plants resulted in increases in growth (both fresh and dry shoot mass, silique number, length and mass) and pigment content (total chlorophyll and carotenoids). Excessive B levels increased the activities of antioxidant enzymes, including superoxide dismutase, catalase, ascorbate peroxidase, and guaiacol peroxidase, and increased the proline content in leaves of plants. However, treatment of the B-stressed plants with EBL further enhanced the activities of the antioxidant enzymes and increased the content of proline. The high level of lipid peroxidation in plants observed during exposure to a higher level of BA was decreased following EBL treatment. Thus, this study showed that the exogenous application of EBL ameliorates the toxic effects of B in a model plant by improving the plant’s antioxidant system and decreasing B accumulation. To our knowledge, this is the one of the first studies to examine the effect of BR in plants subjected to B toxicity.  相似文献   
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Plant Cell, Tissue and Organ Culture (PCTOC) - Diosgenin is an important precursor of steroidal drugs and a number of biotechnology techniques, including gene transfer and elicitation studies, are...  相似文献   
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A new species, Centaurea serpentinica A. Duran & B. Doğan (Asteraceae) in sect. Acrolophus (Cass.) DC., is described and illustrated from Anatolia, Turkey. The species grows on eroded serpentine stony slopes and in open Pinus brutia Ten. forest in the Yahyalı district (C5 Kayseri Province) in the central and south Anatolia transition zone. It is morphologically similar to Centaurea kilaea Boiss. Diagnostic morphological characters from closely similar taxa are discussed and arranged in a key. Ecology, conservation status and biogeography of the species is also presented. In addition, the geographical distribution of the new species and other related species is mapped.  相似文献   
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