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101.
102.
The aim of this study was to determine the prognostic value of single and paired measurements of serum concentrations of human chorionic gonadotrophin (HCG) for successful pregnancy following in-vitro fertilization (IVF) and tubal embryo transfer (TET). We analysed serum HCG concentrations 15 and 22 days after IVF or TET in 198 conception cycles. Cut-off values of serum HCG were determined by a receiver operating characteristic (ROC) curve. On the basis of single HCG samples on day 15 (HCG15) after transfer, using a cut-off value of HCG15 = 150 mIU/ml, the sensitivity was 71% and the specificity was 77%. The positive predictive value (HCG15 > or = 150 mIU/ml indicating a normal pregnancy) was 89%, while the negative predictive rate (HCG15 < 150 mIU/ml indicating an abnormal pregnancy) was 51%. Patients with HCG15 < 150 mIU/ml but HCG22/HCG15 ratio > or = 15, still had a 90% chance of normal pregnancy. However, in patients with HCG15 < 150 mIU/ml and an HCG22/HCG15 ratio < 15, there was an 84% chance of an abnormal pregnancy. We conclude that a single HCG15 determination combined with the ratio of HCG22 to HCG15 has a higher diagnostic accuracy for prediction of pregnancy outcome than either analysis alone. 相似文献
103.
Putative control of angiogenesis in hemangioblastomas by the von Hippel-Lindau tumor suppressor gene
The hypoxia-inducible endothelial cell-specific mitogen vascular endothelial growth factor/vascular permeability factor (VEGF/VPF) is expressed in low amounts in adult human brain, but is highly upregulated in the perinecrotic palisading cells of glioblastomas. We observed high VEGF expression in cerebellar hemangioblastomas, which are highly vascular, nonnecrotic and presumably nonhypoxic tumors, and hypothesized that a mechanism other than hypoxia leads to VEGF upregulation. Because hemangioblastomas develop in patients with von Hippel-Lindau disease, and mutations of the von Hippel-Lindau tumor suppressor (VHL) gene have also been reported in sporadic hemangioblastomas, we investigated VHL expression in normal cerebellum and in hemangioblastomas and tested the hypothesis that mutations in the VHL gene lead to upregulation of VEGE We observed constitutive expression of VHL mRNA, but downregulation of VEGF mRNA in the postnatal cerebellum. In the adult cerebellum, VHL is predominantly expressed in neuronal cells. In hemangioblastomas, VHL expression appears to be restricted to stromal cells, suggesting that the neoplastic component is the stromal cell. VHL-deficient renal cell carcinoma cells (786-0) produced significantly higher levels of VEGF mRNA and protein compared with 786-0/ wt10 cells, which were stably transfected with the wild-type VHL gene. Our observations suggest that VHL mutations affect stromal cells in hemangioblastomas and that VEGF is upregulated in stromal cells as a consequence of mutations in the VHL gene. 相似文献
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105.
OBJECTIVE: The present study set out to determine general levels of distress, anxiety and depression in an obstetric-gynaecology inpatient population and to ascertain levels of patient satisfaction with services. METHOD: 200 English-speaking consecutive admissions to the hospital filled out a package of questionnaires consisting of a demographic data form, the 30-item General Health Questionnaire, the Speilberger State-Trait Anxiety Inventory, the Inventory to Diagnose Depression and a Patient Satisfaction with Services Questionnaire. 134 packages were fully completed. RESULTS: The most significant findings were: first, that high levels of anxiety prevailed, with approximately 1/3 of patients at or above the 75th percentile for anxiety levels; and second, that those patients born in non-English speaking countries were significantly more dissatisfied with their care. CONCLUSIONS: The results of this study suggest that there is a need for increased awareness of and further research into the psychological needs of obstetric-gynaecology patients. 相似文献
106.
MA van Rossum TJ Fiselier MJ Franssen AH Zwinderman R ten Cate LW van Suijlekom-Smit WH van Luijk RM van Soesbergen NM Wulffraat JC Oostveen W Kuis PF Dijkstra CF van Ede BA Dijkmans 《Canadian Metallurgical Quarterly》1998,41(5):808-816
AIMS: To determine whether left ventricular volumes and ejection fractions calculated from single plane two-dimensional echocardiograms using the algorithm (0.85A2L) correlate with those calculated using the biplane Simpson's method, and whether small changes in volumes and ejection fraction occurring post-infarction could be detected from single-plane as well as from biplane two-dimensional echocardiograms. METHODS AND RESULTS: Serial two-dimensional echocardiograms were obtained in 371 patients from the DEFIANT II trial a mean of 2 days, 1 week and 6 months post-infarction. Single plane volumes from the apical four chamber and apical long axis correlated closely with biplane Simpson's left ventricular volumes. Both single-plane left ventricular volumes significantly over-estimated biplane Simpson's volumes. Biplane Simpson's ejection fractions were consistently slightly under-estimated from the single-plane images. Differences between biplane Simpson's and single-plane volumes increased independently with increasing left ventricular size and distortion. The small changes in left ventricular volumes and ejection fraction over time were as reliably detected from single plane as from biplane images. CONCLUSION: Single-plane left ventricular volumes over-estimate biplane Simpson's volumes and under-estimate ejection fraction, and these discrepancies are amplified in dilated hearts with abnormal shape. 相似文献
107.
108.
KH Türmer M Smitka A Guhl J Br?uning I Kreissig 《Canadian Metallurgical Quarterly》1994,204(4):229-234
BACKGROUND: Borrelia burgdorferi is difficult to detect in synovial fluid, which limits our understanding of the pathogenesis of Lyme arthritis, particularly when arthritis persists despite antibiotic therapy. METHODS: Using the polymerase chain reaction (PCR), we attempted to detect B. burgdorferi DNA in joint-fluid samples obtained over a 17-year period. The samples were tested in two separate laboratories with four sets of primers and probes, three of which target plasmid DNA that encodes outer-surface protein A (OspA). RESULTS: B. burgdorferi DNA was detected in 75 of 88 patients with Lyme arthritis (85 percent) and in none of 64 control patients. Each of the three OspA primer-probe sets was sensitive, and the results were moderately concordant in the two laboratories (kappa = 0.54 to 0.73). Of 73 patients with Lyme arthritis that was untreated or treated with only short courses of oral antibiotics, 70 (96 percent) had positive PCR results. In contrast, of 19 patients who received either parenteral antibiotics or long courses of oral antibiotics (> or = 1 month), only 7 (37 percent) had positive tests (P < 0.001). None of these seven patients had received more than two months of oral antibiotic treatment or more than three weeks of intravenous antibiotic treatment. Of 10 patients with chronic arthritis (continuous joint inflammation for one year or more) despite multiple courses of antibiotics, 7 had consistently negative tests in samples obtained three months to two years after treatment. CONCLUSIONS: PCR testing can detect B. burgdorferi DNA in synovial fluid. This test may be able to show whether Lyme arthritis that persists after antibiotic treatment is due to persistence of the spirochete. 相似文献
109.
BH Yoon R Romero JK Jun KH Park JD Park F Ghezzi BI Kim 《Canadian Metallurgical Quarterly》1997,177(4):825-830
OBJECTIVE: Our purpose was to test the hypothesis that neonates who develop bronchopulmonary dysplasia have higher amniotic fluid concentrations of proinflammatory cytokines than those who do not develop bronchopulmonary dysplasia. STUDY DESIGN: The relationship between amniotic fluid concentrations of interleukin-6, tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-8 and the occurrence of bronchopulmonary dysplasia in the neonate was examined in 69 patients who were delivered of preterm neonates (< or = 33 weeks) within 5 days of amniocentesis. Cytokines were measured by specific immunoassays. RESULTS: Bronchopulmonary dysplasia was diagnosed in 19% (13/69) of newborns. Median amniotic fluid concentrations of interleukin-6, tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-8 concentrations were significantly higher in mothers whose infants had bronchopulmonary dysplasia than in mothers whose infants did not have bronchopulmonary dysplasia (p < 0.05 for each). Neonates who had bronchopulmonary dysplasia were delivered at earlier gestational ages and had lower birth weights than those without bronchopulmonary dysplasia. The differences in median amniotic fluid interleukin-6, interleukin-1 beta, and interleukin-8 between these two groups remained significant after we adjusted for the effect of gestational age at birth (p < 0.05 for each). CONCLUSIONS: (1) Antenatal exposure to proinflammatory cytokines is a risk factor for the development of bronchopulmonary dysplasia; (2) the injury responsible for bronchopulmonary dysplasia in a subset of neonates may begin before birth. 相似文献
110.
KH Kilburn 《Canadian Metallurgical Quarterly》1997,90(10):997-1006
BACKGROUND: In the 19th century, deaths from acute exposure to hydrogen sulfide (H2S) portended permanent brain injury from nonlethal doses. The neurobehavioral effects of H2S exposures lasting from moments to years were compared in 16 subjects, 2 years to 22 years afterward. METHODS: Neurophysiologic and psychologic tests were used to appraise mood status and frequencies of 35 symptoms. Functions and frequencies, described as percent predicted adjusted for age, sex, educational achievement, and other factors, were compared with those in an unexposed population. RESULTS: Frequencies were elevated for 31 of 33 symptoms. Balance was impaired (246% predicted with eyes closed, 159% predicted with eyes open), and simple and choice reaction times were prolonged (151% and 130% predicted, respectively). Visual fields performance was decreased to 72% predicted (right) and 55% predicted (left), color discrimination was abnormal, and hearing was decreased. Psychologic domains showed cognitive disability, reduced perceptual motor speed, impaired verbal recall and remote memory, and abnormal mood status. CONCLUSIONS: Exposure to H2S must be avoided. 相似文献