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991.
992.
Background: Several papers have called for a trial of planned cesarean section versus planned vaginal birth for low‐risk women—a recommendation that is fiercely debated. Although proponents of a trial have voiced their support, evidence suggests that in the United Kingdom few midwives and obstetricians believe such a trial to be feasible, and no studies reporting women's views on the prospect of such a trial have been published. The purpose of this study is to explore women's views of participation in a trial of planned cesarean birth versus planned vaginal birth. Methods: A qualitative study was conducted using in‐depth interviews in a large maternity hospital in the United Kingdom. Sixty‐four women were interviewed 12 months after giving birth. Women were asked “How do you think you would have felt if you had been approached to take part in such a trial during your first pregnancy?” Data were analyzed thematically. Results: Only 3 of the 64 women stated that they would have participated in a trial of planned vaginal birth versus planned cesarean section, had they been asked. However, five other women said that they would have consented to participate if they had been asked during pregnancy, but with hindsight, would have regretted that decision. The remainder of women would not have participated, unless a preference arm was offered. Three main themes were identified: “feeling cheated,”“let nature take its course, ” and “just another trauma that you don't need.” Conclusions: Few women supported a trial and most suggested that it was intuitively wrong. Given the strong views voiced by women, it is unlikely that a trial of planned vaginal delivery versus planned cesarean delivery would be feasible. 相似文献
993.
Amanda Henderson PhD RN RM David Shum PhD † Wai-Tong Chien MN RN ‡ 《Health expectations》2006,9(1):13-24
AIM: This exploratory pilot study developed and tested the validity of picture cards as a strategy to ascertain patients' desired participation in decision making. These were then used to ascertain characteristics of Hong Kong Chinese patients' decision-making preferences for surgery. VALIDATION OF TOOL: Two sets of analyses tested the validity of picture cards in an Australian and Hong Kong Chinese population. First, the ratings of the two groups of participants using the picture cards for three scenarios (severe, moderate and mild medical conditions) were correlated with mean ratings of three decision-making subscales of a self-report questionnaire for the three scenarios. Second, a 3 (Scenario) x 2 (Ethnic Group) mixed anova examined whether the picture cards are sensitive to differences relating to severity of medical conditions and ethnicity. SETTING AND PARTICIPANTS: A convenience sample of initially 35 Hong Kong and 24 Australian patients was used to validate the picture card tool. A convenience sample of a further 186 Hong Kong Chinese surgical inpatients used the tool. DESIGN: Participants selected the picture card that best represented their decision-making preference. MAIN VARIABLES: Demographic factors, prior knowledge, nature of surgery and preference for participation in decision making. RESULTS: Significant correlations were made between the questionnaire and the picture card tool. Using the tool, a significant difference was found between males' and females' decision-making preference, yet, no significant difference was found with respect to type or previous surgical operation. 相似文献
994.
995.
Polycyclic aromatic hydrocarbon-DNA adducts in human placenta and modulation by CYP1A1 induction and genotype 总被引:6,自引:1,他引:5
Whyatt RM; Bell DA; Jedrychowski W; Santella RM; Garte SJ; Cosma G; Manchester DK; Young TL; Cooper TB; Ottman R; Perera FP 《Carcinogenesis》1998,19(8):1389-1392
This study investigated the relationship in human placenta between
polycyclic aromatic hydrocabon (PAH)-DNA adduct levels and two biomarkers
of cytochrome P4501A1 (CYP1A1): gene induction evidenced by CYP1A1 mRNA,
and a genetic polymorphism, the CYP1A1 MspI RFLP. CYP1A1 codes for an
inducible enzyme system that catalyzes the bioactivation of PAHs. Prior
research found a high correlation in human lung tissue between CYP1A1
activity and DNA damage from PAHs. The CYP1A1 Mspi RFLP has been linked in
some studies to risk of lung cancer. The relationships in human placenta
between DNA damage, CYP1A1 activity and genotype have not been well
characterized and may be relevant to risks from transplacental PAH
exposure. The study cohort consisted of 70 newborns from Krakow, Poland, a
city with elevated air pollution, and 90 newborns from nearby Limanowa, an
area with lower air pollution but greater indoor coal use. Contrary to
results seen previously in lung tissue, CYP1A1 mRNA was not significantly
correlated with PAH-DNA adduct levels in the placenta. Smoking
(self-reported maternal and infant plasma cotinine) was significantly
associated with CYP1A1 mRNA levels (P < 0.01), but not with PAH-DNA
adduct levels. Placental PAH- DNA adduct levels were significantly higher
in infants with the CYP1A1 MspI restriction site compared with infants
without the restriction site (P < 0.01), implicating a genetic factor in
inter-individual variation in DNA damage in human placenta. Further studies
are needed to determine the relevance of this finding to risk of
transplacental carcinogenesis.
相似文献
996.
997.
Dendritic cells and macrophages can mature independently from a human bone marrow-derived, post-colony-forming unit intermediate 总被引:7,自引:4,他引:7
Szabolcs P; Avigan D; Gezelter S; Ciocon DH; Moore MA; Steinman RM; Young JW 《Blood》1996,87(11):4520-4530
CD34+ precursors in normal human bone marrow (BM) generate large numbers of dendritic cells alongside macrophages and granulocytic precursors when cultured for 12 to 14 days in c-kit ligand, granulocyte- macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor-alpha (TNF-alpha). This study reports an intermediate cell type that develops by day 6, and has the potential to differentiate into either macrophages or dendritic cells. When the d6 progeny are depleted of mature macrophages and residual CD34+ precursors, a discrete CD14+ HLA-DR+ population persists in addition to immunostimulatory CD14- HLA- DR() dendritic cells. Half of the CD14+ HLA-DR+ population is in cell cycle (Ki-67+), but colony-forming units (CFUs) are no longer detectable. The calls are c-fms+, but lack myeloperoxidase and nonspecific esterase. They also possess substantial phagocytic and allostimulatory activity. These post-CFU, CD14+ HLA-DR+ intermediates develop into typical macrophages when recultured in the absence of exogenous cytokines. M-CSF supports up to approximately 2.5-fold expansion of macrophage progeny. In contrast, the combination of GM-CSF and TNF-alpha supports quantitative differentiation into dendritic cells, lacking c-fms, CD14, and other macrophage properties, and expressing HLA-DR, CD1a, CD83, CD80, CD86, and potent allostimulatory activity. Therefore, normal CD34+ BM precursors can generate a post-CFU bipotential intermediate in the presence of c-kit ligand, GM-CSF, and TNF-alpha. This intermediate cell type will develop along the dendritic cell pathway when macrophages are removed and GM-CSF and TNF-alpha are provided. Alternatively, it can differentiate along a macrophage pathway when recultured with or without M-CSF. 相似文献
998.
Several lines of evidence indicated that P cell-stimulating factor (PSF), a T lymphocyte-derived lymphokine known to stimulate the growth of hemopoietic stem and progenitor cells, also acted on macrophages. PSF was absorbed from medium that had been mixed for two hours at 0 degrees C with either resident or thioglycollate-elicited peritoneal cells, suggesting the presence of receptors for PSF on cells in the population. The addition of pure PSF to populations highly enriched in either resident or elicited adherent peritoneal macrophages resulted in stimulation of macrophages with morphological changes, including increases in size, spreading, vacuolation, and the number of cytoplasmic processes, together with stimulation of proliferation and the phagocytosis of opsonized yeast. PSF also stimulated the incorporation of [3H]thymidine by bone marrow-derived adherent macrophages. Addition of pure PSF to cultures that contained only a single macrophage resulted in enhanced survival and proliferation of these isolated cells, demonstrating that the effect of PSF on macrophages was direct. These results indicate that PSF can stimulate well-differentiated functional macrophages and raise the possibility that the effects of PSF on macrophages may play a regulatory role in immune responses. 相似文献
999.
Two patients with thrombotic thrombocytopenic purpura (TTP) have recovered completely after intensive plasmapheresis. The mechanisms responsible for the improvement in these instances are most likely related to the removal of an inciting or damaging agent. The possibility that this agent may be an immune complex is discussed. Plasmapheresis appears to be useful therapy for some patients with this syndrome. 相似文献
1000.
Lowenthal RM; Buskard NA; Goldman JM; Spiers AS; Bergier N; Graubner M; Galton DA 《Blood》1975,46(6):835-844
Intensive leukapheresis has been used as the initial treatment of chronic granulocytic leukemia (CGL) in six patients. The number of leukaphereses ranged from 3 in 7 days to 13 in 39 days (mean, 8 in 22 days). The procedures were well tolerated, and in all patients there was improvement in hematologic values, in most cases with considerable reduction in the peripheral leukocytosis and thrombocytosis and in the proportion of immature granulocytic cells in the circulation. Splenomegaly decreased considerably in the four patients who had more than four leukaphereses. Symptoms of sweating, malaise, and pain due to splenomegaly were rapidly relieved. Problems due to hyperuricemia did not occur, but four patients required blood transfusions for correction of anemia. This method of initial treatment of CGL appears to give more rapid relief of symptoms than does conventional chemotherapy; it incurs no risk of hyperuricemia and lessens that associated with thrombocytosis. In addition, large quantities of granulocyte-rich plasma are made available for the treatment of infections in neutropenic patients. Intensive leukapheresis deserves more widespread evaluation as the initial treatment of CGL. 相似文献