Author Keywords: Event-related potentials; females; menstrual cycle 相似文献
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51.
52.
Social-psychological predictors of self-reported actual and intended physical activity in a university workforce sample. 总被引:2,自引:1,他引:1 下载免费PDF全文
This study investigated the social-psychological predictors of self-reported actual and intended physical activity in a university workforce sample. Based on the 'Theory of Planned Behaviour', but with additional variables of benefits, barriers and self-efficacy, it was found that both intended and actual activity could be predicted but only when strenuous activity was considered. In addition, the predictors were different for men and women. Specifically, the best predictors of intention to exercise were attitude, perceived control, benefits and self-efficacy for women, but only attitude for men. Predicting self-reported strenuous activity for women were intention and self-efficacy, and for men intention and attitude. Theoretical and practical implications for attitude research and exercise promotion are discussed. 相似文献
53.
Nancy Kluck Sean O'Connor Victor Hesselbrock Allan Tasman Donald Maier Lance Bauer 《Progress in neuro-psychopharmacology & biological psychiatry》1992,16(6):901-911
Nancy Kluck, Scan J. O'Connor, Victor M. Hesselbrock, Allan Tasman and Donald Maier, Lance Bauer: Variation in Evoked Potential Measures Over the Menstrual Cycle: A Pilot Study. Prog. Neuro. Psychopharmacol. Biol. Psychiat. 1992. 16(6): 901–911.
1. 1. The P3 component of a visual event related potential (ERP) was studied for five consecutive weeks in six women with normal menstrual cycles. Serum concentrations of luteinizing hormone (LH), estradiol (E2) and progesterone were studied during the same period.
2. 2. Increases in P3 amplitude, although nonsignificant, were noted in the week preceding onset of menses.
3. 3. No significant changes in reaction times to target/nontarget stimuli were noted over the same time period.
54.
Correction of severe secondary hyperparathyroidism in two dialysis patients: surgical removal versus percutaneous ethanol injection. 总被引:1,自引:0,他引:1
B Page J Zingraff J C Souberbielle G Coutris E Sarfati T Drüeke J F Moreau 《American journal of kidney diseases》1992,19(4):378-381
Two chronic hemodialysis patients had recurrent, severe secondary hyperparathyroidism. The first had no sonographically visible parathyroid gland in the neck. Computed tomography (CT) scan indicated the existence of a parathyroid mass in the upper mediastinum, which was removed surgically. The second patient had two intracervical, hyperplastic parathyroid glands visible on ultrasound examination. He volunteered for nonsurgical removal via sonographically guided percutaneous injection of ethanol. In both patients, serum total calcium concentration decreased dramatically to values near 1.5 mmol/L 24 hours after treatment. In patient 1, serum immunoreactive parathyroid hormone (iPTH) (1-84) decreased from 1,582 pg/mL before surgery to 34 pg/mL after 24 hours (normal range, 10 to 65 pg/mL). In contrast, serum iPTH (1-84) decreased only progressively in patient 2, from 1,680 pg/mL before ethanol injection to 865 pg/mL after 24 hours and to 378 pg/mL after 72 hours to reach 30 pg/mL after 14 days. Thus, patient 2 had a striking decrease of plasma calcium immediately after parathyroid gland destruction, even though circulating iPTH was still very high. The reason for such a discrepancy remains unexplained at present, and further study will be necessary to solve this issue. 相似文献
55.
This paper describes the ring-opening methathesis polymerization of homopolymers and copolymers of exo- and endo-2-cyanobicyclo[2.2.1]hept-5-ene (norbornenenitrile) in solution. Polymerization kinetics were followed via 1H NMR spectroscopy in real time while the final polymer microstructure was determined via 13C NMR. While pure endo monomer does not polymerize readily, it copolymerizes with exo monomer, rapidly and to high conversions. The structure of the copolymer appears to be quite similar to that of exo homopolymer. We conclude that exo monomer adds directly to either exo or endo, while endo-endo addition is sterically hindered. 相似文献
56.
Raymer P. Grant Cliff Morgan Michael S. Page David N. Malm Victor Huckel Leonard C. Jenkins 《Journal canadien d'anesthésie》1990,37(4):409-415
Dipyridamole thallium scanning (DTS) is an imaging technique with good sensitivity for coronary artery disease (CAD). The purpose of this study was to compare the haemodynamic courses and the correlation between pulmonary capillary wedge pressure (PCWP) and central venous pressure (CVP) in patients with normal DTS (Group 1: n = 12) with those whose scans demonstrated CAD (Group2: n = 11). Haemodynamic profiles were obtained prior to anaesthesia and at several times during surgery. The haemodynamic courses in both groups were similar with significant decreases in cardiac index, stroke index, and left ventricular stroke work index during aortic cross-clamping compared with values prior to anaesthesia. There were no significant changes in PCWP and CVP throughout the study. The correlations between PCWP and CVP were significant in both groups as were the correlations between the changes in PCWP and the changes in CVP observed at the time of cross-clamping. These correlations all had large standard errors of the estimate, however, making it impossible to predict the PCWP from the CVP with precision. It is concluded that, in a limited study population, an abnormal DTS did not identify patients in whom the PCWP and CVP correlated poorly during abdominal aortic aneurysmectomy. 相似文献
57.
Sean Sullivan 《International journal of mental health and addiction》2007,5(4):381-389
The EIGHT Screen is a brief problem gambling screen originally designed for use by family doctors. Its wider use indicated
the need for further validation. A triangulated approach used a range of measures in different settings in both the current
study and findings from a number of earlier projects, and reviewed current use. The EIGHT Screen had acceptable correlations
with the SOGS (r = 74–90%) and with the NODS-12 months Screen (r = 62.4%). Measurements remained relatively constant amongst a range of cultures, settings, age and gender, while few false
positives were produced by the screen. The EIGHT Screen appears to be a valid tool for untrained users to identify Level 2
and 3 problem gambling in a wide range of cultures and settings. 相似文献
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The distinction between seminoma and embryonal carcinoma based on morphology alone can sometimes be problematic, requiring the use of immunohistochemistry to facilitate diagnosis. D2-40 is a monoclonal antibody that reacts with an oncofetal antigen expressed by fetal germ cells and testicular germ cell tumors. The diagnostic value of D2-40 immunohistochemistry in distinguishing seminoma from embryonal carcinoma has not been determined. D2-40 immunoreactivity was evaluated in a series of testicular germ cell tumors and compared with that of KIT (CD117) and CD30, to assess the relative utility of this marker in discriminating between seminoma and embryonal carcinoma. Forty testicular germ cell neoplasms were examined, which included 19 seminomas, three embryonal carcinomas, three teratomas, one yolk sac tumor, and 14 mixed germ cell tumors. The 14 cases of mixed germ cell tumors contained components of seminoma (n=7), embryonal carcinoma (n=11), teratoma (n=10), yolk sac tumor (n=2), and choriocarcinoma (n=1). All cases of pure seminoma and the seminomatous components of mixed germ cell tumors exhibited positive immunoreactivity for D2-40. Focal positivity for D2-40 was also observed in 29% of the embryonal carcinoma samples. D2-40 immunoreactivity in seminomas was characterized by diffuse membrane staining, whereas for embryonal carcinomas, staining was focal and distributed along the apical surfaces of the neoplastic cells. Immunohistochemical staining for KIT was observed in 92% of the seminoma samples and in none of the embryonal carcinomas. Conversely, CD30 expression was identified in 93% of the embryonal carcinoma samples and in none of the seminomas. Other germ cell components showed no immunoreactivity for D2-40, KIT, or CD30. KIT and CD30 are effective immunohistochemical markers in separating seminoma from embryonal carcinoma. Although a highly sensitive marker for seminomas, D2-40 positivity was also observed in a subset of embryonal carcinomas, thus limiting the utility of this antibody for discriminating between these two malignancies. 相似文献
60.