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251.
Darrell J Gaskin Kevin P Weinfurt Liana D Castel Venita DePuy Yun Li Andrew Balshem Al Benson Caroline B Burnett Sandra Corbett John Marshall Elyse Slater Daniel P Sulmasy David Van Echo Neal J Meropol Kevin A Schulman 《Medical decision making》2004,24(6):614-624
OBJECTIVE: The authors sought to empirically test whether relative health stock, a measure of patients' sense of loss in their health due to illness, influences the treatment decisions of patients facing life-threatening conditions. Specifically, they estimated the effect of relative health stock on advanced cancer patients' decisions to participate in phase I clinical trials. METHOD: A multicenter study was conducted to survey 328 advanced cancer patients who were offered the opportunity to participate in phase I trials. The authors asked patients to estimate the probabilities of therapeutic benefits and toxicity, their relative health stock, risk preference, and the importance of quality of life. RESULTS: Controlling for health-related quality of life, an increase in relative health stock by 10 percentage points reduced the odds of choosing to participate in a phase I trial by 16% (odds ratio = 0.84, 95% confidence interval = 0.72, 0.97). CONCLUSION: Relative health stock affects advanced cancer patients' treatment decisions. 相似文献
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BACKGROUND: Phytoestrogens are a family of plant-derived compounds with weak estrogenic and antiestrogenic properties. The antioxidant capacity of phytoestrogens has been proposed as one of the important mechanisms that explain their health benefits. OBJECTIVE: To determine the in vitro potency of three phytoestrogens, ubiquitous in food, (biochanin A, daidzein and genistein) as antioxidants of low density lipoprotein (LDL) and to compare them with the well-established antioxidant actions of estradiol and quercetin, an ubiquitous flavonoid which is found in high concentration in onions, tea and berries. METHODS: LDL was isolated by ultracentrifugation from the plasma of ten healthy postmenopausal women who were not on hormone therapy. Aliquots containing 0.5 mg of protein were incubated for 4 h with CuSO4 15 micromol/l to induce oxidative stress and with one of the five compounds studied: estradiol, quercetin, biochanin A, daidzein, and genistein, in doses of 0, 5, 15, 50, 500, 1000 and 2000 micromol/l. In addition, we studied the combined effect of estradiol 1 micromol/l plus quercetin 1 micromol/l, comparing their antioxidant action with that of each compound separately. Malonaldehyde (MDE nmol/ mg protein) was measured as a marker of LDL oxidation. RESULTS: Estradiol and quercetin induced a dose-dependent decrease in MDE concentration (p < 0.01). Comparing the areas under the curve, the antioxidant effect of quercetin was 8 times higher than the one observed with estradiol (p < 0.01). A 50% decrease in MDE was reached by quercetin at a concentration of 3.4 micromol/l, estradiol at 29 micromol/l, genistein at 280 micromol/l, biochanin at 1312 mmol/l and daidzein at 8007 mmol/l. Estradiol 1 micromol/l and quercetin 1 micromol/l did not modify MDE generation separately, but, when incubated combined, there was a significant decrease of MDE (p < 0.02). CONCLUSION: The phytoestrogens studied showed a weak antioxidant activity in vitro. The flavonoid quercetin, in contrast, showed the most potent antioxidant activity in vitro, higher than estradiol. Estradiol and quercetin showed additive antioxidant activity. We speculate that different compounds with variable antioxidant effects could amplify their antioxidant capacity when acting combined. 相似文献
256.
SC Perni 《The Ultrasound Review of Obstetrics & Gynecology》2004,4(2):81-92
With the increasing incidence of multifetal gestations, it is essential for the clinician to appreciate the benefit of ultrasound evaluation in these pregnancies. Multifetal gestation pregnancies are at increased risk for a range of both antepartum and intrapartum complications, such as intrauterine growth restriction, premature delivery, congenital anomalies, cord accidents, malpresentations, placenta previa, and abruptio placentae. First-trimester ultrasonic evaluation, amniotic fluid assessment, monitoring of fetal growth, diagnosing the twin-to-twin transfusion syndrome, and assessment of fetal anomalies will be reviewed. An early and accurate assessment of amnionicity and chorionicity are paramount in these gestations. The impact of chorionicity, in particular, can have profound consequences in the management of multifetal gestations. The determination of chorionicity onultrasonic evaluation in a multifetal gestations. The determination of chorionicity on ultrasonic evaluation in a multifetal pregnancy should be determined in a systematic way between 10-14 weeks' gestation. The amniotic fluid volume should be routinely assessed when performing an ultrasonic evaluation in a multifetal pregnancy. Amniotic fluid changes may serve as the only useful indicator to a potential pathological condition. In addition, evaluation of fetal growth in twins is essential, because these pregnancies are at increased risk for growth restriction and increased perinatal mortality rates compared to singletons. Finally, a careful anatomical evaluation in mulitifetal gestation is important because twin pregnancies have higher rates of anomalies than their singleton counterparts. 相似文献
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Ige AO Bolam JP Billinton A White JH Marshall FH Emson PC 《Brain research. Molecular brain research》2000,83(1-2):72-80
Following the recent discovery that GABA(B) receptors expressed in cell lines are only functional when both GABA(B1) and GABA(B2) are expressed, the present study reports on the development of polyclonal antisera specific for carboxyl-terminal portions of the two related GABA(B) receptor components respectively. Western blotting indicated the specificity of affinity-purified antibodies for native or recombinant expressed GABA(BR1) and GABA(BR2), with no cross-reactivity, both antisera detecting the heterodimer in rat cerebellar membranes. Immunohistochemistry revealed a distinct distribution of both receptor proteins in rat cerebellum. GABA(B1) immunoreactivity was primarily located in the granule cell layer and Purkinje cells, with discrete immuno-positive cell bodies being present in the molecular layer. GABA(B2) staining revealed intense immunoreactivity in the molecular layer, with weaker staining in the granule cell layer. Purkinje cell bodies were less intensely immuno-positive for GABA(B2). Co-localisation of both receptor proteins was observed using double immunofluorescence techniques, consistent with the notion that both proteins are required for the formation of functional GABA(B) receptors in vivo. Immunofluorescence also indicated that GABA(B) receptors did not co-localise with glial fibrillary acid protein, confirming a neuronal localisation for GABA(B) receptors. Electron microscopic analysis of the molecular layer revealed that the distribution of immunolabelling for both GABA(B1) and GABA(B2) was mainly located on the membrane of Purkinje cell dendrites and spines and in parallel fibre terminals. 相似文献
259.
OBJECTIVES: To determine, first, the prevalence and severity of various symptoms related to estrogen deficiency in women within a few years of receiving treatment for breast cancer, second, how women perceive the effects of these symptoms on their quality of life and, third, what measures have been taken to relieve vasomotor symptoms. METHODS: Two hundred women (aged 29-65 years) who had received treatment for breast cancer within the last 5 years were included in this cross-sectional survey. Information was collected about their breast cancer treatment, menopausal symptoms (Menopausal Rating Scale), the perceived effects of menopausal symptoms on their and their partner's quality of life and any treatments they were receiving for hot flushes. RESULTS: All but one woman reported at least one symptom related to the menopause (95.9% vasomotor; 83.3% psychological; 89.7% somatic). Current treatment with tamoxifen or previous chemotherapy did not influence the prevalence or the severity of hot flushes. Current antidepressant treatment was, however, significantly associated with a higher prevalence and severity of most menopausal symptoms, including hot flushes and sweats (p = 0.008). The severity of hot flushes and sweats was significantly correlated with self-assessed effects on overall quality of life (r(s) = 0.47); 56.4% of the respondents believed that menopausal symptoms had affected their partner's quality of life, the strongest correlations being with severity of sexual symptoms (r(s) = 0.56) and vaginal dryness (r(s) = 0.5). Only 21% of women experiencing hot flushes were receiving any treatment for hot flushes, with most women describing no knowledge or poor knowledge of treatment options. CONCLUSIONS: The majority of women receiving treatment for breast cancer report menopausal symptoms, which negatively correlate, not only with their own, but also with their partner's quality of life. Most women experiencing hot flushes are not receiving treatment due to lack of both awareness and confidence in the existing treatment options. 相似文献
260.
Releasing information to families of persons with severe mental illness: a survey of NAMI members 总被引:2,自引:0,他引:2
OBJECTIVE: Guidelines for the treatment of severe mental illness recommend that providers share information with families and involve them in treatment. However, research indicates that consumer-provider-family collaboration is not part of routine clinical practice. This study examined the process of releasing information to families and the types of information they receive. METHODS: Self-administered surveys were completed by 219 family and consumer members of the National Alliance for the Mentally Ill. The surveys gathered information about their experiences with providers' releasing information. Consumers' attitudes toward collaboration and family members' satisfaction with providers were also measured. Regression analyses examined the relationship between consumers' attitudes toward family involvement and whether providers discussed family involvement or the release of information with consumers. Further analyses examined the relationship between family satisfaction and release of information. RESULTS: The majority of family respondents (72 percent) reported that they received some specific information about their relative's mental illness. Most families received information about diagnosis and medications, but few received information about the treatment plan. Few consumers reported that their permission was requested to release information to their families. Consumers' attitudes toward their family and toward family involvement were significantly associated with whether they were encouraged by their provider to involve a family member in their treatment. No significant relationship was found between consumers' attitudes and whether their provider discussed the release of information. Family members' satisfaction was positively related to whether they received information from providers. CONCLUSIONS: The findings suggest that although some information is shared with families, collaboration is not currently part of routine clinical practice. 相似文献