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31.
32.
Eating disorders and obesity (EDO) are increasing among youth, having serious long-term physical and psychological consequences. The purpose of this study was to determine if significant differences exist in EDO risk factors following participation of 4–6th grade students in a school-based EDO prevention curriculum. This community-based research project assessed students at baseline and one week following EDO intervention. Primary outcome variables measured self-esteem, body dissatisfaction, and high risk eating attitudes and behaviors. Pre and post-test differences were calculated using mixed models, correcting for clustering within schools and teachers. This study found mean changes in all scores in healthy directions, as well as movement of students into lower risk groups post-intervention. This program demonstrated that a classroom curriculum is associated with decreased risks of EDO in boys and girls, supporting prevention programs at an early age for both sexes. Studies to determine long term benefit and guide booster interventions are warranted.  相似文献   
33.
This study critically examines the concepts of dignity and liminality at the end-of-life, in an effort to better understand the processes of healing within suffering among Chinese terminal cancer patients receiving palliative care services in Hong Kong. Meaning-oriented interviews were conducted with 18 Chinese terminal patients, aged 44 to 98, to elicit the narratives and stories of their illness experience. All interviews were analyzed using grounded theory and supplemented by ethnographic observations and field notes. Two major themes and eight subprocesses of healing adopted by patients to achieve and maintain dignity were identified: (a) personal autonomy, which encompasses the need to (i) regain control over living environments, (ii) maintain self-sufficiency despite institutional care, (ii) make informed care decisions to reduce sense of burden, and (iv) engage in future planning to create a lasting legacy; and (b) family connectedness, which encompasses the need to (i) maintain close ties with family members to express appreciation, (ii) achieve reconciliation, (iii) fulfill family obligations, and (iv) establish a continuing bond that transcends generations. Implications of these themes for advanced care planning and life review interventions were discussed with the goal of enhancing patient autonomy and family connectedness, and thereby providing structure and meaning for Chinese terminal patients and their families at the end of life.  相似文献   
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35.
乔凤霞  周兰芳  张均田 《药学学报》1994,29(11):814-817
妊娠末期催产素刺激子宫蜕膜细胞产生与分娩有关的前列腺素,但其作用方式仍未知。本实验分离妊娠19d大鼠蜕膜细胞,测定了催产素作用后蜕膜细胞内游离钙的变化,结果加入0.001~1μmol·L-1催产素后,蜕膜细胞内[Ca2+]i出现瞬息增加,其峰值与催产素浓度呈剂量依赖关系,且此作用有自身钝化现象。说明催产素可能激活妊娠末期大鼠蜕膜细胞内的肌醇磷酯蛋白激酶C系统。给妊娠末期大鼠ip硫酸去氢表雄酮钠盐后分离的蜕膜细胞,催产素作用引起[Ca2+]i瞬息增加峰值较对照升高。  相似文献   
36.
Shattil  SJ; Motulsky  HJ; Insel  PA; Flaherty  L; Brass  LF 《Blood》1986,68(6):1224-1231
Epinephrine causes platelet aggregation and secretion by interacting with alpha 2-adrenergic receptors on the platelet surface. Platelet aggregation requires the binding of fibrinogen to a specific receptor on the membrane glycoprotein IIb-IIIa complex. Although the IIb-IIIa complex is identifiable on the surface of resting platelets, the fibrinogen receptor is expressed only after platelet activation. The current studies were designed to examine the effect of occupancy of platelet alpha 2-adrenergic receptors by epinephrine on the expression of fibrinogen receptors and on the aggregation of platelets. The ability of epinephrine to induce the expression of fibrinogen receptors was studied under two different conditions: acute stimulation (less than 1 min) and prolonged stimulation (50 to 90 min), the latter of which is associated with a reduction or "desensitization" of the platelet aggregation response. Expression of the fibrinogen receptor was monitored with 125I-fibrinogen as well as with 125I-PAC-1 (PAC-1), a monoclonal antibody that binds to the glycoprotein IIb-IIIa complex only after platelets are activated. Epinephrine caused an immediate increase in PAC-1 and fibrinogen binding that was dependent on occupancy of the alpha 2-receptor by epinephrine and on the presence of extracellular free Ca (KCa = 30 mumol/L). By itself, 1 mmol/L Mg was unable to support induction of the fibrinogen receptor by epinephrine. However, it did decrease the Ca requirement by about two orders of magnitude. Prolonged stimulation of unstirred platelets by epinephrine led to a 70% decrease in the aggregation response when the platelets were subsequently stirred. Despite their decreased aggregation response, desensitized platelets bound PAC-1 and fibrinogen normally, indicating that the loss of aggregation was not due simply to a decrease in fibrinogen receptor expression. Although desensitization was not affected by pretreatment of the platelets with aspirin, it was partially prevented when extracellular Ca was chelated by EDTA during the long incubation with epinephrine. These studies demonstrate that once platelet alpha 2-adrenergic receptors are occupied by epinephrine, extracellular Ca is involved in initiating the aggregation response by supporting the induction of the fibrinogen receptor and the binding of fibrinogen. Furthermore. Ca-dependent reactions subsequent to fibrinogen binding may be necessary for maximal platelet aggregation and are impaired when platelets become desensitized to epinephrine.  相似文献   
37.
The effects of acetylcholine on the spontaneous activity of the AV node of dog hearts were studied by recording transmembrane potentials of its fibers. Action potentials of most nodal fibers were characterized by prominent phase 4 depolarization and a smooth transition from phases 4 to 0. On the isolated AV nodes, acetylcholine at 1.0 μg/m1 suppressed the rate of phase 4 depolarization and increased the amplitude of the maximum diastolic potential, resulting in a slowing of spontaneous activity. At 2.0 μg/m1, spontaneous activity was completely suppressed. In comparison, spontaneous activity of the isolated His bundle was relatively insensitive to the suppressive effect of acetylcholine at the same concentrations. In the AV node-His bundle preparations in which the AV node was the pacemaker, acetylcholine decreased spontaneous activity by suppressing the phase 4 depolarization of the nodal fibers and shifted the pacemaker of the preparation to the His bundle. The findings provide a basis for predicting that under strong vagal influence, the automaticity of the AV node will be suppressed and the pacemaker of the junctional rhythm will be located at the His bundle.  相似文献   
38.
Krigel  R; Liebes  LF; Pelle  E; Silber  R 《Blood》1982,60(1):272-275
Two patients with progressive hairy cell leukemia following splenectomy were treated with low-dose daily chlorambucil. Both had an objective hematologic response as determined by a return to normal hematocrit and platelet count. This was also reflected in the mononuclear cell fraction by the normalization of cholesterol content, cholesterol/phospholipid ratio, and the lymphocyte subpopulations. This article confirms previous reports on the efficacy of chlorambucil in this setting and describes some morphological, and biochemical concomitant events.  相似文献   
39.
Background: We conducted a meta-analysis to assess the overall risk of cardiac toxicity associated with trastuzumab treatment in elderly breast cancer patients.

Methods: We searched databases from PubMed, EMBASE and Cochrane Central Registry of Controlled Trials to identify relevant studies. Statistical analyses were conducted to calculate the incidence rate, overall hazard ratio (HR) and 95% CIs using a fixed effects model.

Results: A total of 116,342 and 360 elderly patients from five cohort studies and two randomized clinical trials (RCTs) were included for analysis. The pooled incidences of symptomatic congestive heart failure (CHF) and CHF/HF/CM were 6.4% (95% CI 4.1% – 9.4) and 16.4% (95% CI 16.19% – 16.61) in patients with median age of 67.5 years from two RCTs and in patients with median age of 67.5 (60 – 75), 71 (66 – 80+), 74.5 (65 – 89), 75 (66 – 81+) and 79.5 (60 – 99) from five cohort studies, respectively. Trastuzumab was significantly correlated with an increased risk of defined cardiac toxicities in five cohort studies (HR = 1.89, 95% CI 1.72 – 2.07, p < 0.00001) and two RCTs (HR = 3.00, 95% CI 1.71, 5.26, p < 0.00001). Sub-group analysis showed that the anthracycline-based chemotherapy increased the risk of CHF/HF and CM in patients among five cohort studies (HR = 2.16, 95% CI: 1.8 – 1.87, p < 0.00001).

Conclusion: Trastuzumab is likely associated with an increased risk of cardiac toxicity in elderly patients with HER-2-positive breast cancer. Carefully monitoring cardiac function in elderly patients receiving trastuzumab, particularly with concurrent use of anthracycline, is warranted.  相似文献   

40.
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