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21.
Neonatal respiratory distress syndrome (RDS) is one of the biggest problems in modern obstetrics. The incidence of RDS is 1%-2%. RDS is a condition of insufficient surfactant production. Surfactant is a complex molecule which is responsible for maturation of fetal lungs. The most important factor for insufficient surfactant production and pulmonary immaturity is shortening of gestation, i.e. preterm delivery. Antenatal corticosteroids for maturation of fetal lungs are in use for over thirty years. Corticosteroids decrease the incidence and intensity of RDS, the severity of intracerebral hemorrhage, and overall neonatal morbidity and mortality. The mechanism of corticosteroid action is probably induction of fetal pulmonary enzyme complex that is responsible for adequate surfactant production and regulation of pulmonary interstitial fluids. In this literature review, we analyze long- and short-term benefits and risks of single and multiple antenatal corticosteroid administration.  相似文献   
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nm23-H1 expression and loss of heterozygosity in colon adenocarcinoma   总被引:18,自引:0,他引:18  
BACKGROUND: The discovery that genetic alterations in oncogenes and tumour suppressor genes accompany tumour formation in many human tumours has encouraged the search for genes that promote or suppress tumour spread and metastasis; nm23 is a promising candidate for a metastasis suppressing gene.AIMS: To evaluate whether expression of nm23-H1 protein or loss of heterozygosity (LOH) of the nm23-H1 gene is associated with colon cancer progression. MATERIALS/METHODS: Paraffin wax embedded tissue sections were analysed immunohistochemically. DNA isolated from normal and tumour tissue was used for LOH analysis using a variable nucleotide tandem repeat (VNTR) marker located in the untranslated 5' region of the nm23-H1 gene. RNA isolated from tumour and normal tissue was used for "real time" RT-PCR. RESULTS: Of 102 adenocarcinomas examined, 58.8% stained weakly for nm23-H1 protein. There was a negative correlation between nm23-H1 positivity and tumour histological grade. In VNTR analysis, 70.2% of patients were informative and 27.4% of tumours had nm23-H1 LOH. There was a positive correlation between nm23-H1 LOH and both tumour histological grade and Dukes's stage. Expression of nm23-H1 mRNA was increased in 22 of 30 colon tumours compared with normal tissue. No significant correlation was found between nm23-H1 mRNA expression and histological grade or Dukes's stage of tumours. CONCLUSIONS: These findings suggest that nm23-H1 protein expression in early stages may have a role in suppressing metastasis in sporadic colon cancer, whereas at a later stage both reduced nm23-H1 protein expression and LOH of the nm23-H1 gene may play role in colon cancer progression and metastasis.  相似文献   
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Countertransference in therapists working with patients with posttraumatic stress disorder (PTSD) differs from countertransference in other psychotherapeutical settings. In this article we discuss the specificities of counter- transference in treating PTSD patients and its relation to empathy. The most difficult countertransference problems occur in treating multiply traumatized patients. Countertransference may occur towards an event (e.g., war), patients who have killed people, as well as to colleagues who avoid treating PTSD patients, or towards a supervisor who avoids, either directly or indirectly, supervision of therapists working with PTSD patients. Our recommendation for the prevention of problems in treating PTSD patients include : 1) careful selection of the therapist or helper, both in the personality structure and training; 2) prevention by debriefing and team work and peer supervision; and 3) education - theoretical, practical, and therapeutical.  相似文献   
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The localization of the A-rafcellular oncogene on the mouse X chromosome has been determined using Xbal-restricted DNAs prepared from progeny of an interspecies backcross between the B6.CBA.R1 and the Spe/Pas mouse strains. This localization to the proximal part of the mouse X chromosome has been confirmed by the use of somatic cell hybrids, carrying partially deleted X chromosomes and suggests that the A-raf oncogene localizes to a region lying some 10–17 centimorgans proximal to the hypoxanthine phosphoribosyltransferase (Hprt) gene between the locus DXPas4and the locus DXPas7defined by the cross-reacting human X chromosome-specific probe DXS32 (M2C). This localization on the mouse X chromosome is compatible with the presence of the A-rafoncogene on the short arm of the human X chromosome between the centromere and Xp21.  相似文献   
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In the present paper, we studied the effect of natural zeolite clinoptilolite on sphingolipid metabolism in the yeast Yarrowia lipolytica. We also investigated if zeolite addition had any impact on cell shape and size, as well as on the pH alterations during the culture growth. High performance liquid chromatography analysis of sphingoid bases obtained by acid hydrolysis of complex sphingolipids from Y. lipolytica showed that their concentrations markedly rose upon the zeolite addition. The largest increase among the identified molecular species of sphingoid bases was seen in C18 phytosphingosine, whose levels rose 6.2-fold and 22.3-fold after culturing cells for 24 and 36 hours respectively in the presence of finely ground zeolite. pH measurements of the culture medium showed a similarity between pH profiles of control and zeolite-supplemented cells, suggesting that ion-exchange capacity was not probably responsible for the observed change in sphingolipid metabolism. Scanning electron microscopy revealed that zeolite affected cell size and shape. Y. lipolytica cells grown in the absence of zeolite were oval-shaped with an average cell size of 0.7-2.7 microns, whereas when cultured with zeolite, they were round-shaped and larger, having an average cell size of 1.3-2.9 microns.  相似文献   
30.
Results of treatment of 13 patients fulfilling the criteria for TTP are presented. Thrombocytopenia was present in all patients (100%). Eleven of 13 patients (84.6%) had conciousness disorder, and seven of 13 patients (53.8%) had renal impairment. Immunosuppressive therapy with plasmapheresis and replacement of removed volume with fresh frozen plasma in a dosage of 25 ml/kg body weight resulted in statistically significant increase of platelet count (p = 0.0033), and significant improvement of consciousness as defined by increased Glasgow Coma Score (GCS) (p = 0.0524). In two patients, renal function recovered and, in one patient, hemodialysis was no longer needed. This improvement in a small patient group has no statistical significance.  相似文献   
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