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31.
OBJECTIVE: Depression after hip fracture surgery is prevalent and associated with increased mortality rates and impaired functional recovery. The incidence of new-onset depressive symptoms in patients initially not depressed after hip fracture surgery and their relationship with functional recovery is unknown. METHODS: A cohort of 139 nondepressed elderly patients (>60 years) hospitalized for hip fracture surgery were followed up for six months. Clinically significant depressive symptoms were defined as a score of 7 or more on the 15-item Geriatric Depression Scale. RESULTS: The authors found a cumulative incidence rate of 20.5% adjusted for dropouts. Multiple Cox-regression analyses yielded the presence of subthreshold symptoms of depression, anxiety, pain, and cognitive impairment at baseline, the premorbid level of mobility, and a history of (treated) depression as risk factors for incident depression (p <0.05). A forward, conditional procedure identified postoperative pain (hazard ratio [HR] = 1.32, 95% confidence interval [CI]: 1.14-1.53, Wald chi(2) = 13.57, df = 1, p <0.001) and baseline anxiety (HR = 1.25, 95% CI: 1.08-1.44, Wald chi(2) = 8.86, df = 1, p = 0.003) as the strongest independent risk factors. Incident depression was associated with a less favorable outcome at 3 months follow-up. CONCLUSION: This exploratory study identified two treatable baseline characteristics that predicted incident depression in nondepressed patients after hip-fracture surgery.  相似文献   
32.
The case describes a female patient with squamous cell carcinoma of the lung who initially presented with mechanical upper-back and neck pain. She had been successfully treated with spinal manipulation for a similar complaint one year earlier, a factor that decreased the suspicion of pathological process on her second presentation. Serious disease as the cause of back pain must be considered in cases with certain historical factors, or when the patient fails to respond to treatment for mechanical back pain.  相似文献   
33.
The oxidation of body fuel stores in cancer patients.   总被引:1,自引:0,他引:1       下载免费PDF全文
In an attempt to define the mechanism of weight loss in cancer patients, fat and carbohydrate oxidation rates were calculated in 93 patients. Seventy patients with colorectal or gastric cancer were compared with a control group of 23 patients with nonmalignant illness. Twenty-seven patients with cancer and 13 control patients had lost more than 10% of their pre-illness body weight. Fat and carbohydrate oxidation rates were derived from measurements of oxygen consumption, carbon dioxide production, and urinary nitrogen excretion. Patients with cancer had significantly higher fat oxidation rates (p less than 0.01) and significantly lower carbohydrate oxidation rates (p less than 0.05) when compared with controls. Weight-losing cancer patients had significantly higher fat oxidation rates when compared with weight-stable cancer patients (p less than 0.02), weight-stable controls (p less than 0.01), and weight-losing controls (p less than 0.02). Cancer patients with liver metastases (N = 14) had significantly higher fat oxidation rates (p less than 0.01) and significantly lower carbohydrate oxidation rates (p less than 0.01) compared with cancer patients who had localized disease. There were no significant differences among the groups with respect to resting energy expenditure when expressed as kilocalorie per kilogram lean body mass per day. The presence of cancer appears to be associated with abnormal fat and carbohydrate metabolism. The increased rate of fat oxidation seen in patients with cancer, especially those with weight loss or liver metastases, may be a significant factor in the development of cancer cachexia.  相似文献   
34.
This study examined whether relationships between anger expression, hostility, social evaluative anxiety, and a presumed mechanism for coronary heart disease development, cardiovascular reactivity (CVR) to stress, are moderated by stress situation and gender and whether such relationships are attenuated by inadequate assessments. Subjects (47 men, 47 women) were assigned randomly to either a Harassment or a Social Evaluation condition, under which they performed a reaction time task. SBP, DBP, and HR measures were recorded during baseline and task. Multiple regression analyses indicated that expressed anger was related to CVR only among men in the Harassment condition; that hostile men who express anger showed the most CVR across situations, and that the traits assessed here did not predict CVR among women. Results suggest that assessments of coronary-risk and interventions to reduce risk may need to take into account attitudes, styles of emotional expression, environmental factors, and gender.This research was supported in part by an NIMH predoctoral fellowship (F31MH09836) awarded to John W. Burns and by a grant from the American Heart Association (89-01-3G) awarded to Edward S. Katkin.  相似文献   
35.
In a review of 51 consecutive patients with previously untreated squamous cell carcinoma of the supraglottic larynx, five (9.8%) patients were found to have no mucosal abnormality on initial evaluation by both computed tomography (CT) and direct laryngoscopy. All five patients who manifested submucosal disease had at least one endoscopic procedure done with a biopsy negative for cancer before definitive diagnosis, resulting in an average delay from initial endoscopy to diagnosis of 19.8 weeks. These inapparent or "silent" neoplasms present unique problems in regard to establishing a diagnosis by routine biopsy techniques, even though CT reliably demonstrates their presence. Early diagnosis requires aggressive biopsy techniques based on CT findings.  相似文献   
36.
We report on the use of an instrument to measure exposure to stressors among 149 women presenting with their children for pediatric care at an urban primary care center. Overall, 38.3 percent of the women had significant levels of depressive symptoms; 71.4 percent of those in the "high stress" group had an adjusted prevalence odds ratio of 5.00 [95% CI = 2.12, 11.82]. We conclude that screening in the pediatric office is feasible for identifying women at high risk of becoming depressed.  相似文献   
37.
Erythrocyte transketolase activation by thiamin diphosphate has been studied in elderly patients with moderate or severe chronic dementia, acute alcoholic admissions and chronic alcoholics with evidence of brain damage, mostly of the Wernicke-Korsakoff type. Significantly more patients in each group than controls showed abnormal activation of transketolase, not only by 0.3 mM thiamin diphosphate (TDP) but also in further activation by increase to 3 mM. This indicated the presence in a proportion of the alcoholic and the demented patients of an abnormal enzyme variant, similar to that previously found in vitro. The modified transketolase activation test may warn not only of marginal thiamin deficiency but also independently, of susceptibility to brain damage in patients at risk.  相似文献   
38.
Thrombocytopenia frequently complicates systemic infection and results from multiple possible mechanisms. We and others have demonstrated that platelet-associated IgG (PAIgG) levels are elevated in the majority of patients with septic thrombocytopenia. Corticosteroids may be undesirable as a treatment for thrombocytopenia for patients with severe infection because of their potential for suppressing the immune response. We hypothesized that septic thrombocytopenia is, in most cases, an immune disorder analogous to idiopathic thrombocytopenic purpura (ITP) which might respond to intravenous gamma-globulin as a treatment for increasing the platelet count in this disorder. Intravenous immune globulin (IVIG), 400 mg/kg daily for 3 days, was administered in a randomized double-blind placebo-controlled trial. Twenty-nine patients who developed thrombocytopenia during a documented, septic episode were studied. Patients with disseminated intravascular coagulation (DIC), hypersplenism, or drugs known to cause thrombocytopenia were excluded. Elevated PAIgG levels were documented in 52% of evaluable patients. Mean platelet counts in the IVIG group rose from 43K at study entry to 178K (411% rise) by Day 9. In the placebo group platelets rose from 51K to 125K (261% rise;P = 0.02). Seventy-seven percent of the IVIG group had a minimum peak rise of 35K, vs 56% of the placebo group. Three patients in the placebo group had a serious bleeding episode, vs one in the IVIG group. The use of IVIG to treat septic thrombocytopenia not associated with DIC leads to a more rapid, more sustained, and greater increase in platelet count than placebo. Its use is recommended in the septic patient who is bleeding or is likely to need invasive or surgical procedures.  相似文献   
39.
A quantitative study of various aspects of platelet function was carried out in eight patients with typical hairy-cell leukaemia (HCL). In at least two patients platelet aggregation was convincingly reduced to more than one aggregating agent (ADP, adrenaline, collagen, thrombin, and ristocetin). Granular storage capacity for {(14)C} 5-HT was reduced in five of the six patients tested. The two patients with definitely abnormal aggregation had the greatest reduction in granular storage pool and the longest bleeding times of those tested but, like the other patients, they did not have a clinical haemostatic defect. It was concluded that a granular storage pool defect (SPD) was at least partly responsible for aggregation abnormalities in HCL since the platelet release reaction in response to thrombin appeared to be normal. All our patients ran a chronic course uncomplicated by any of the factors known to predispose to a platelet SPD acquired in the circulation. Although in the one patient tested before and after splenectomy there was some improvement in platelet aggregation after operation, there was no clear general relationship between defective platelet function and either previous splenectomy or platelet count. Since a direct involvement of the megakaryocytic series in the underlying cell proliferation of HCL seems unlikely, it is concluded that the platelet defect can most reasonably be attributed to the production of abnormal platelets as a result of marrow fibrosis and/or infiltration by hairy cells.  相似文献   
40.
Modern medical environments have seen an increase in technological complexity and pressures of handling more patients with fewer resources, resulting in higher demands on medical practitioners. Medical informatics designers will have to focus on the problem of organizing medical information more effectively to enable practitioners to cope with these challenges. This article addresses this research problem for the particular area of medical problem solving in patient care. First, we describe a traditional modeling approach for medical reasoning used as a basis for developing some decision support systems. We argue these models may be faithful to what is known about biomedical knowledge, but they have limitations for human problem solving, especially in unanticipated situations. Second, we present an ontological framework, known as the abstraction hierarchy (Rasmussen, IEEE Trans. Man. Cybernetics 15 (1985) 234-243), for integrating patient representations that are faithful to existing biomedical knowledge and that are consistent with what is known about human problem solving. Through an example of a critical event in the operating room, we reveal how this framework can support medical problem solving in unanticipated situations. Third, we show how to use these representations as a frame of reference for mapping medical roles, responsibilities, sensors, and controls in an operating room context. Finally, we provide some insight for medical informatics designers in using this framework to design novel training programs and human-computer displays.  相似文献   
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