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171.
Chapman B 《CAP today / College of American Pathologists》1994,8(8):1, 30-2, 34 passim
172.
Giuseppe Botta Aldo D'Angelo Giovanni D'Ari Gianfranco Merlino Michael Chapman Gedis Grudzinskas 《Journal of assisted reproduction and genetics》1995,12(3):187-190
Objectives To investigate the potential advantages of epidural anesthesia in an in vitro fertilization and embryo transfer program.Study Design Between January 1991 and December 1992, 148 infertile patients underwent transvaginal ultrasound guided oocyte retrieval. A total of 44 patients (group A) had 50 retrievals under epidural anesthesia, and 104 patients (group B, control group) 112 retrievals under intravenous sedation (propofol) with mask-assisted ventilation (nitrous oxide).Results In group A satisfactory anesthesia was achieved in 49 of the 50 cases (98%); one patient required additional intravenous administration of propofol owing to extreme anxiety. No complications were observed. Adversely, in group B nausea was observed in 16 cases (14%) and nausea and vomiting in 7 cases (6%). In group A the fertilization, cleavage and pregnancy rates were 67.2%, 92% and 20% respectively, while in group B the rates were 69.3%, 93% and 19.6% respectively; the differences are not statistically significant.Conclusions Epidural anesthesia is an effective method for transvaginal oocyte retrieval but does not improve the treatment outcome as compared to an intravenous sedation with mask-assisted ventilation using propofol and nitrous oxide. 相似文献
173.
A chemical phosphatase, butanedione monoxime (BDM, at 12–20 mM), reduced open probability (P
0) of single cardiac L-type Ca2+ channels in cellattached patches from guinea-pig ventricular myocytes, without effect on the amplitude of single-channel current, the mean open time or the mean shorter closed time, but it increased mean longer closed time and caused a fall in channel availability. A decrease in the mean time between first channel opening and last closing within a trace was principally due to an inhibition of the longer periods of activity. As a result, the time course of the mean currents, which resolved into an exponentially declining and a sustained component, was changed by an increase in the rate of the exponential phase and a profound reduction of the sustained current. Essentially similar results were obtained when studying whole-cell Ba2+ currents. The inactivation of the whole-cell Ca2+ currents was composed of two exponentially declining components with the slower showing a significantly greater sensitivity to BDM, an effect that was much more pronounced in myocytes exposed to isoprenaline with adenosine 5-O-(3-thiotriphosphate) (ATP[S]) in the pipette solution. The actions of BDM, which are the opposite of those produced by isoprenaline, suggest that the level of phosphorylation affects processes involved in the slow regulation of channel activity under basal conditions and that several sites (and probably several kinases) are involved. Channels with an inherently slow inactivation would seem to be converted into channels with a rapid inactivation by a dephosphorylation process. 相似文献
174.
Chapman B 《CAP today / College of American Pathologists》1995,9(10):1, 14, 16 passim
175.
176.
Interaction of family history of breast cancer and dietary antioxidants with breast cancer risk (New York,United States) 总被引:1,自引:0,他引:1
Christine B. Ambrosone James R. Marshall John E. Vena Rosemary Laughlin Saxon Graham Takuma Nemoto Jo L. Freudenheim 《Cancer causes & control : CCC》1995,6(5):407-415
We sought to determine if specific dietary antioxidants may be particularly effective in reducing breast cancer risk for women reporting family history (FH) of breast cancer in a first-degree relative. Interviews regarding usual diet, health, and family histories were conducted with 262 premenopausal and 371 postmenopausal women with incident, primary breast cancer from western New York (United States). These women were frequencymatched by age and county of residence with community controls. Among premenopausal women, there was a significant interaction between FH and -tocopherol; -tocopherol was associated with significantly decreased risk among FH+ women (adjusted fourth-quartile odds ratio [OR]=0.01, 95 percent confidence interval [CI]=0.0–0.3). This association was much weaker for FH-women [OR=0.7, CI=0.4–1.2]. For FH-women, a significant inverse association was observed between -carotene and premenopausal breast-cancer risk (OR=0.4, CI=0.3–0.5), but not for FH+ women (OR=0.5, CI=0.1–4.0). Similar relationships, although not as strong, were noted among postmenopausal women. Although limited by small numbers, these results suggest that biologic mechanisms of tumorigenesis may differ in FH+ and FH-women, and that -tocopherol may be a potential chemopreventive agent for women with a family history of breast cancer, particularly premenopausal women.This research was conducted by the Department of Social and preventive Medicine, State University of New York at Buffalo. This publication is supported in part by grants CA11535 and 5 R25 CA1820117 from the US National Cancer Institute and PDT-434 from the American Cancer Society. Dr Freudenheim is a recipient of a Research Career Development Award from the National Cancer Institute (CA01633). This work is solely the responsibility of the authors and does not necessarily represent the views of the NCI. 相似文献
177.
Michael J. Millward David R. Newell Kally Yuen Jane P. Matthews Kathryn Balmanno Christopher J. Charlton Lindsey Gumbrell Michael J. Lind Fiona Chapman Madeleine Proctor Dorothy Simmonds Brian M. J. Cantwell A. Hilary Calvert 《Cancer chemotherapy and pharmacology》1995,37(1-2):161-167
The pharmacokinetics and pharmacodynamics of prolonged oral etoposide chemotherapy were investigated in 15 women with metastatic breast cancer who received oral etoposide 100 mg as a single daily dose for up to 15 days. There was considerable interpatient variability in the day 1 pharmacokinetic parameters: area under the plasma concentration time curve (AUC) (0–24 h) 1.95±0.87 mg/ml per min (mean ± SD), apparent oral clearance 60.9±21.7 ml/min per 1.73 m2, peak plasma concentration 5.6±2.5 g/ml, time to peak concentration 73±35 min and half-life 220±83 min. However, intrapatient variability in systemic exposure to etoposide was much less with repeated doses. The intrapatient coefficient of variation (CV) of AUC for day 8 relative to day 1 was 20% and for day 15 relative to day 1 was 15%, compared to the day 1 interpatient CV of 45%. Neutropenia was the principal toxicity. Day 1 pharmacokinetic parameters were related to the percentage decrease in absolute neutrophil count using the sigmoidal Emax equation. A good fit was found between day 1 AUC and neutrophil toxicity (R
2=0.77). All patients who had a day 1 AUC>2.0 mg/ml per min had WHO grade III or IV neutropenia. The predictive performance of the models for neutrophil toxicity was better for AUC (percentage mean predictive error 5%, percentage root mean square error 18.1%) than apparent oral clearance, peak plasma concentration, or daily dose (mg/m2). A limited sampling strategy was developed to predict AUC using a linear regression model incorporating a patient effect. Data sets were divided into training and test sets. The AUC could be estimated using a model utilizing plasma etoposide concentration at only two time points, 4 h and 6 h after oral dosing (R
2=98.9%). The equation AUCpr=–0.376+0.631×C4h+0.336×C6h was validated on the test set with a relative mean predictive error of –0.88% and relative root mean square error of 6.4%. These results suggest monitoring of AUC to predict subsequent myelosuppression as a strategy for future trials with oral etoposide.Division of Haematology and Medical Oncology, Peter MacCallum Cancer Institute, Locked Bag 1, A'Beckett St, Melbourne 3000, Australia 相似文献
178.
M. E. Shelton P. J. Chapman S. S. Foss W. S. Fisher 《Archives of environmental contamination and toxicology》1999,36(1):13-20
Artificially weathered crude oil was degraded by four diverse cultures of mixed marine bacteria under optimized conditions
for 7 and 14 days. Loss in total weight of starting oil (30 g) ranged from 6.8–17.3% in biologically active incubations compared
with only 0.9–1.1% in sterile and nutrient-limited controls. In all incubations, both neutral and acidic water-soluble fractions
(WSF) were accumulated. In biologically active systems, 50.9–249.0 mg neutral and 63.3–406.8 mg acidic WSF were accumulated
whereas only 6.5–11.1 mg neutral and 1.7–2.2 mg acidic WSF were accumulated in control incubations. Analysis by gas chromatography
demonstrated that accumulated WSF in biologically active systems contained compounds different from those washed from the
starting crude oil. Exposure of grass shrimp (Palaemonetes pugio) embryos to neutral WSF from each of the biologically active cultures resulted in high embryo mortalities relative to sterile
and nutrient-limited controls which exhibited >90% hatching success and larval survival. Toxicity of neutral WSF was also
demonstrated on larvae of mysids (Mysidopsis bahia). In both cases, toxicity occurred only on exposure to neutral material accumulated by active, oil-degrading cultures and
not with material washed from the weathered crude oil. These results imply that unique compounds were accumulated during degradation
that may have been responsible for increased toxicity.
Received: 23 December 1997/Accepted: 27 July 1998 相似文献
179.
The authors examined potential associations between air-pollution exposures and respiratory symptoms and illnesses of 4,108 adults who resided in 4 districts of 3 large, distinct Chinese cities. Data on respiratory health outcomes and relevant risk factors for parents and children were obtained via standardized questionnaires in the winter of 1988. (The effects in children were described previously.) The yearly averages of ambient levels of total suspended particles in the 4 districts for the years 1985-1988 differed greatly. The authors constructed logistic-regression models to assess the respiratory health parameters of parents of the children. The results revealed significant and strong effects, by district, on prevalence rates of cough, phlegm, persistent cough and phlegm, and wheeze for both the mothers and the fathers. In addition, the odds ratios increased as ambient total suspended particle concentration increased across the 3 urban districts. Other local within-city risk factors, however, may have confounded the total suspended particles-effects association, especially for asthma prevalence. Findings for adults were similar to those found for their children. A strong adverse effect of active tobacco smoking on the fathers' respiratory health was observed. The children appeared to be more strongly affected by passive smoking exposure received in their homes than their mothers. 相似文献
180.