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This is a qualitative study of clinicians' use of partial information disclosure and its consequences for adolescents' ability to participate in the management of their cancer treatment. A total of 17 pediatric cancer patients, their families, and clinicians were observed during 15 months of ethnographic fieldwork in a hospital in Barcelona, Spain. Eighty-six hours of videotaped medical and social activities were analyzed micro-interactionally and longitudinally. Clinicians used 4 strategies to evade direct answers to adolescents' questions: contingent answers, narrow answers, non-answer responses, and question forestalling. Information withholding by clinicians was shown to greatly limit adolescents' ability to participate in the management of their treatment and to be ineffective in its implicit goals of protecting the patient and containing uncertainty and anxiety. The author concludes that if clinicians were to integrate adolescents' individual information needs into their communicative practices they would be able to better assess what information to disclose as well as how and when to disclose it.  相似文献   
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PURPOSE: A laboratory investigation was undertaken to assess the effects of propofol on renal function, through modulation of the systemic inflammatory response, in an in vivo experimental model of aortic surgery in comparison with sevoflurane. METHODS: Twenty young male piglets were anesthetized with either propofol 4 mg.kg(-1).hr(-1) (n = 10) or sevoflurane 1.5% end-tidal concentration (n = 10). Animals were subjected to aorta-aortic bypass with suprarenal aortic clamping for 30 min. At specific intervals (basal -before the start of surgery; reperfusion 15 min after unclamping the aorta; at 24, 48 and 72 hr after surgery, and on the seventh day after surgery) the levels of the following were determined: plasma creatinine, renal myeloperoxidase, tumour necrosis factor-alpha, interleukin 1-ss, and interferon-gamma; kidney superoxide anion and its detoxifying enzyme superoxidase dismutase, kidney malondialdehyde and the activity of inducible nitric oxide synthase. Seven days after surgery, the animals were anesthetized using the described techniques, and after blood withdrawal and kidney sampling they were sacrificed. RESULTS: In comparison with sevoflurane, propofol was associated with a lower concentration of plasma creatinine (P < 0.05) together with lower concentrations of myeloperoxidase, tumour necrosis factor-alpha, interleukin 1-ss, interferon-gamma, superoxide anion and superoxidase dismutase, malondialdehyde and inducible nitric oxide synthase (P < 0.05). CONCLUSION: In an experimental model of aortic reconstructive surgery, and compared with sevoflurane, propofol anesthesia is associated with less neutrophil infiltration, lower plasma proinflammatory cytokine levels, lower production of oxygen free radicals, less lipid peroxidation, and reduced inducible nitric oxide synthase activity. These observations suggest a possible renal protective effect of propofol in this surgical setting.  相似文献   
4.
The intensity dependence of the auditory-evoked potentials (IDAP) is inversely related to serotonergic tone. Depression is frequently observed after stroke, associated with cognitive impairment and increased mortality. Aim of this study was to investigate the serotonergic tone in acute stroke patients by IDAP. Consecutive patients with an acute stroke admitted in our stroke unit were evaluated using clinical and instrumental examinations and compared with healthy controls. The IDAP was calculated as the linear amplitude/stimulus intensity function (ASF) slope, by measuring the peak-to-peak amplitude of Nl-P2 on four blocks of different stimulus intensities. Twenty patients were enrolled; 11 had a right brain infarction; nine had depressive symptoms (DS). The ASF slope of the auditory-evoked potentials was markedly increased in stroke patients compared with controls ( P  = 0.021). Stroke patients with DS had a significant steeper ASF slope than controls ( P  = 0.017). There was no statistical difference in ASF slope between stroke patients without DS and controls. Post-stroke depression pathophysiology is still debated. Our study suggests that in acute stroke patients with DS, there is a direct involvement of the serotonergic system, regardless the degree of disability and the site of the lesion.  相似文献   
5.
Spectrum of pulmonary nontuberculous mycobacterial infection   总被引:5,自引:0,他引:5  
Miller  WT  Jr 《Radiology》1994,191(2):343
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6.
Basic fibroblast growth factor (bFGF or FGF-2) is present in the basal membrane of pancreatic cells during the pancreatic embryonic development. The expression of bFGF receptors has been described in normal pancreatic cells. By contrast, pancreatic cancer cells express not only the bFGF receptors but also the bFGF itself. With the aim of understanding the effects induced by the production of bFGF by pancreatic cancer cells, the pancreatic acinar cell line (AR4-2J) was used. AR4-2J cells do not produce bFGF but express bFGF receptors. These cells were transfected with a vector containing the bFGF cDNA encoding the three different forms of bFGF characterized in tumor cells. Results showed that the bFGF expression induced important phenotypic and enzymatic modifications. The transfected cells lost some morphological features of the acinar cells and expressed amylase and lipase at low levels (a 90% decrease for amylase activity, whereas lipase activity was barely detectable). These results suggest that bFGF could be involved in maintaining pancreatic cells in a slightly differentiated state.  相似文献   
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BACKGROUND: Equilibration of hemoglobin concentration after transfusion has been estimated to take about 24 hours, but some studies have shown that earlier measurements reflect steady-state values in persons who have not bled recently. This study was aimed at assessing the changes over time in hemoglobin concentration after transfusion in acutely anemic patients because of recent bleeding. STUDY DESIGN AND METHODS: Thirty-two normovolemic patients recovering from an acute bleeding episode who were no longer thought to be bleeding and who received a 2- unit red cell transfusion were studied. At baseline and 15, 30, 60, and 120 minutes and 24 hours after transfusion, hemoglobin concentration and hematocrit values were measured. RESULTS: The administration of 2 units of packed red cells elicited a 24-hour increase of 22.4 +/− 6.8 g per L in hemoglobin concentration. Hemoglobin values were not different at any of the defined posttransfusion times. Hematocrit levels experienced similar changes over time. Agreement between 15-minute and 24-hour values was excellent, as only 6 percent of patients exhibited a clinically significant difference (> 6 g/L) between the hemoglobin measurements. CONCLUSION: Hemoglobin and hematocrit values rapidly equilibrate after transfusion in normovolemic patients who are recovering from an acute bleeding episode. This fact would allow a rapid assessment of the effects of transfusion and of the recurrence of bleeding in patients remaining at risk.  相似文献   
9.
Five hundred six consecutive cases of ductal infiltrating carcinoma of the breast (T1-T2,N0,M0) were evaluated to define the frequency of peritumoral lymphatic invasion (PLI) and verify its possible prognostic significance. Histologically, PLI was characterized by the presence of neoplastic emboli within vascular lumina lined by recognizable endothelial cells, adjacent to but outside the margins of the carcinoma. In routine histopathologic assessment the frequency of PLI was 68% whereas in a randomly selected group of 234 reviewed cases the frequency rose to 20%. Patients with routinely evaluated PLI had a worse prognosis than those without PLI with reference both to disease-free survival (P = 0.0001) and total survival rates (P = 0.0001). The difference for local recurrences was prognostically highly significant (P = 0.0001) and also significant for the development of metastases (P = 0.0576). In the reviewed material the difference in prognosis between PLI-positive and PLI-negative cases was not confirmed for total survival whereas the significance for the disease-free interval persisted. The assessment of PLI, carried out following strict histopathologic criteria, appears to select a group of node-negative breast cancer patients who have an increased risk of recurrences and might benefit from a treatment different from that reserved for node-negative and PLI-negative patients.  相似文献   
10.
目的探讨血脂代谢紊乱跟Ⅱ型糖尿病(ⅡDM)患者继发动脉粥样硬化并症的关系。方法采用奥林巴斯Au-640全自动生化分析仪,测定Ⅱ型糖尿病患者和健康对照组的空腹血糖(GLU)、胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白(HDL-C)、载脂蛋白Al(ApoAl)和载脂蛋白B100(ApoBloo),并进行统计、比较并与患者的病情进行对比分祈,并对高血糖、血脂组患者跟踪观察、治疗。结果Ⅱ型糖尿病组同健康对照组比较、Ⅱ型糖尿病患者中有合并症组跟无合并症组、高血糖组跟血糖正常组比较,CHO、TG和ApoBloo的含量均升高(P<0.05),而HDL-C和ApoAI含量降低(P<0.05)。而高血糖、血脂组患者,已经初步出现或在随后的观察中出现了动脉粥样硬化等相关的临床表征,且治疗效果不佳。结论Ⅱ型糖尿病患者血脂的异常,特别是CHO、TG的大幅升高,提示患者在出现动脉硬化性心血管合并症之前,体内已经具备了诱发合并症的生化基础,应早期采取针性治疗和预防措施。  相似文献   
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