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991.
To investigate whether or not the mode of delivery produces differences in cerebral oxygenation, cerebral hemoglobin oxygen saturation was measured using full-spectrum near infrared spectroscopy in 26 healthy term newborn infants immediately after birth. Infants in group 1 (n=20) were delivered vaginally, and those in group 2 (n=6) by elective cesarean section. Arterial oxygen saturation in the right hand was also measured simultaneously using a pulse oximeter. Changes in arterial oxygen saturation showed no significant difference between the two groups. The mean+/-S.D. of cerebral hemoglobin oxygen saturation in group 1 increased rapidly after birth, from 29+/-17% at 2 min to 68+/-6% at 8.5 min, followed by an almost constant value (66+/-7% at 15 min). In comparison, cerebral hemoglobin oxygen saturation in group 2 also increased rapidly until 8.5 min, but after this time decreased significantly to 57+/-5% at 15 min after birth. This indicates that the mode of delivery has a marked influence on cerebral oxygenation immediately after birth.  相似文献   
992.
The purposes of this study were to examine the characteristics of the relationship between ADL ability and daily life satisfaction and the pattern change with aging in independent Japanese elderly, and to compare these tendencies between males and females. The characteristics of ADL ability and daily life satisfaction of 482 subjects (213 males, 269 females) were investigated in a self-response survey. Seventy-four ADL items, considered from previous studies, were selected from nine ADL domains of 1) movement, 2) going up and down stairs, 3) changing and holding posture, 4) bathing, 5) toileting, 6) dressing, 7) grooming, 8) eating, and 9) manual activities, and nine items of daily life satisfaction were selected from physical, psychological and sociological factors. Both ADL ability and life satisfaction of independent elderly tended to decline with aging. From correlation analysis, since life satisfaction of the elderly was higher with high ADL ability level, it was considered that ADL ability level is one of the important factors in providing for life satisfaction of independent elderly. The subjective symptoms of inconvenience in the lower extremity and lumbar region increased from the 70s in both genders, and the use of assisting devices for movement remarkably increased in the 80s in both genders. The use of assisting devices closely related to the activity area in daily life and influenced the characteristics of life satisfaction and its age-related change in the relationship between ADL ability and life satisfaction. The relationship between ADL ability and satisfaction with physical function was similar in both genders, while the relationship between ADL ability and satisfaction with sociological and psychological factors was different between males and females. Since the relationship between ADL ability and life satisfaction of independent elderly is influenced by a combination of personal, cultural, and environmental factors, additional study must investigate in detail the influence of these factors.  相似文献   
993.
Porcine membrane cofactor protein (pMCP) is abundantly expressed throughout the body with particularly strong expression on the vascular endothelia. Previous studies demonstrated that the promoter of the pMCP gene induced efficient expression of a human complement regulatory protein, decay-accelerating factor (DAF; CD55), in transgenic mice. In the present study, we tried to produce transgenic pigs with two hybrid genes, 0.9/hDAF and 5.4/hDAF, which were composed of human DAF (hDAF) gene regulated under pMCP promoters of different lengths (0.9 and 5.4 kb). Five live founder transgenic pigs were obtained only with the 0.9/hDAF construct. Although, four founder pigs transmitted the transgene to the second generation, the transmission rates varied among founders. We examined the expression of hDAF in tissues of descendants of two lines (Dm1 and Dm4). Human DAF specific RNAs were confirmed by an RT-PCR analysis in all organs examined. Levels of hDAF protein in the organs from the descendants of Dm1 line were higher than those in the corresponding human organs as determined by enzyme-linked immunosorbent assay. Immunohistochemical studies showed that the tissue distribution of hDAF in the descendants of both lines was similar to that of endogenous pMCP. The expression level of hDAF on the vascular endothelial cells in Dm1 line was twice that on the corresponding human cells. We tested whether proinflammatory cytokines upregulate an efficiency of pMCP promoter on hDAF expression in transgenic pigs. Although the expression of hDAF on the human endothelial cells increased with a combination of cytokines, tumor necrosis factor alpha and interferon-gamma, no cytokine-induced upregulation was seen in the cells of transgenic pigs. The endothelial cells from transgenic pigs exhibited high resistance to the human serum-mediated cytolysis.  相似文献   
994.
Endocrine gland-derived vascular endothelial growth factor (EG-VEGF, identical to prokineticin 1) is a novel peptide recently identified as a selective mitogen for endocrine gland endothelial cells. The present study demonstrates that EG-VEGF/prokineticin 1 and a peptide closely related to EG-VEGF, prokineticin 2, are cognate ligands of two orphan G-protein-coupled receptors designated ZAQ (=EG-VEGF/PK-R1) and I5E (=EG-VEGF/PK-R2). EG-VEGF/prokineticin 1 and prokineticin 2 induced a transient increase in intracellular calcium ion concentration ([Ca(2+)](i)) with nanomolar potency in Chinese hamster ovary (CHO) cells expressing EG-VEGF/PK-R1 and -R2 and bind to these cells with high affinity and with different receptor selectivity. EG-VEGF/prokineticins provoke rapid phosphorylation of p44/42 MAP kinase and DNA synthesis in the bovine adrenal capillary endothelial cells (BACE). The mRNAs of both EG-VEGF/PK-R1 and -R2 were expressed in BACE. The identification of the receptors for EG-VEGF/prokineticins may provide a novel molecular basis for the regulation of angiogenesis in endocrine glands.  相似文献   
995.
996.
In the host defense mechanism against feline immunodeficiency virus (FIV) infection, CD8(+) T cells specifically attack virus-infected cells and suppress the replication of the virus in a non-cytolytic manner by secreting soluble factors. In this study, we measured CD8(+) T cell anti-FIV activity in 30 FIV-infected cats. We investigated its relationship with the number of peripheral blood lymphocytes, particularly the CD4(+) T cell and CD8(+) T cell counts, and the relationship between anti-FIV activity and the number of T cells of CD8alpha(+)beta(lo) and CD8alpha(+)beta(-) phenotypes. A clearly significant correlation was observed between anti-FIV activity and the number of CD4(+) T cells. A weaker anti-FIV activity was associated with a greater decrease in the number of CD4(+) T cells. However, there was no significant correlation between anti-FIV activity and the number of B or CD8(+) T cells. Compared with SPF cats, FIV-infected cats had significantly higher CD8alpha(+)beta(lo) T cell and CD8alpha(+)beta(-) T cell counts, but, no significant correlation was observed between these cell counts and anti-FIV activity. This anti-FIV activity significantly correlated with plasma viremia, which was detected in cats with a weak anti-FIV activity. These results suggest that the anti-FIV activity of CD8(+) T cells plays an important role in plasma viremia and the maintenance of CD4(+) T cells in the body. It is unlikely that CD8alpha(+)beta(lo) or CD8alpha(+)beta(-) T cells appearing after FIV infection represent a phenotype of CD8(+) cells with anti-FIV activity.  相似文献   
997.
In the present study, a dialytic method that uses a DNA aqueous solution to remove and enrich dioxins from polluted water was proposed. Circular dichroism (CD) and fluorescent spectra indicated that dibenzo-p-dioxin (DD), dibenzofuran (DF) and biphenyl (BP), which are dioxin derivatives, form complexes with DNA. Their experimental dialytic sorption coefficients were measured by quantifying the concentrations of DD, DF, and BP in aqueous solutions before and after dialysis of the DNA solution, and the values were 2.1×105, 1.3×105, and 1.5×107, respectively. As a simulated water treatment model, DNA solution was dialyzed in an aqueous mixture of DD, DF, and BP for 96 h, the HPLC studies showed that the dioxin derivatives have been concentrated in the DNA solution about 200 times. The dialyzed DNA solution was reusable by an extraction with hexane.  相似文献   
998.
Both the role and source of tumor necrosis factor (TNF-alpha) in lipopolysaccharide (LPS)-induced nasal inflammation were investigated using TNF-alpha gene deficient (TNF-alpha -/-) mice and chimeric mice that are TNF-alpha gene deficient only in bone marrow-derived cells. In the present study, intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) mRNA expression levels in the nasal mucosa were significantly decreased following intranasal instillation of LPS in TNF-alpha gene deficient mice compared to those in wild type mice. In contrast, ICAM-1 and VCAM-1 mRNA expressions were not significantly decreased although TNF-alpha mRNA expression was dramatically decreased in TNF-alpha gene deficient bone marrow-transplanted-chimeric (TNF-alpha -/--->+/+) mice compared to those in wild type bone marrow-transplanted-control (TNF-alpha +/+-->+/+) mice. These results indicate that the elevation of TNF-alpha mRNA in the nasal mucosa is mainly originated from bone marrow-derived cells. However, even low expression of TNF-alpha at local inflammation sites is sufficient to induce the expression of adhesion molecules in acute LPS-induced experimental rhinitis.  相似文献   
999.
Purine 2'-deoxynucleosides bearing an ethynyl or a cyano group at C-4' of the sugar moiety were synthesized from the corresponding 2'-deoxynucleosides. These compounds exhibited very potent anti-HIV activity, and remained active against drug resistant HIV strains.  相似文献   
1000.
Spontaneously developing pocks (S pocks) of Streptomyces azureus ATCC14921 were formed by the both functions of conjugative plasmid pSA1 and lysogenic phage SAt2. The formation was affected by the dose of UV irradiation. The mean pock diameter in cultures treated with UV light at 0, 7.1, 14.2 and 21.3 x 10(2) microW. erg/cm, respectively, were 1.3, 0.4, 2.2, and 0.5 mm. The dose affected conjugative plasmid pSA1 related to pock formation. There was UV damage of autonomous pSA1 replicon and UV induction of the chromosomal integrated sequence. Increases and decreases in the amount of autonomous pSA1 replicon corresponded to increases and decreases, respectively, in the diameter of the pocks. Both pSA1 and SAt2 syntheses were developed in the large pocks (1.3 and 2.2 mm), but only SAt2 synthesis was developed in the pinhole pocks (0.4 and 0.5 mm).  相似文献   
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