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51.
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Strategies based on immunotherapy as a treatment of cancer have been applied clinically for over more than 100 years. However, only the advances produced in the past two decades which changed the understanding of how T lymphocytes recognise and destroy antigenic targets permitted to establish tumour immunology on solid grounds. It is now generally accepted that established tumours represent selected variants that have escaped the surveillance of the individual immune system. Implicit in that idea is the production by tumour cells of certain tumour-specific molecules that can be targeted by the immune system. A great number of altered or even normal proteins have been discovered in the last years that can evoke a tumour-directed immune attack. The induction of anti-tumour immune responses by vaccination with those tumour specific molecules or by treatment with antigen-specific antibodies is now currently under investigation in many clinical trials. Of particular interest is the idiotypic region of the immunoglobulin molecule, which acts as a clonal marker of B-lymphocyte neoplasias: The immunisation of lymphoma patients with their own tumour immunoglobulin has been proved effective in the treatment of that incurable condition.  相似文献   
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OBJECTIVES: To analyze patterns of routine testing before elective/scheduled surgery in healthy/asymptomatic patients classified as ASA I or II according to the American Society of Anesthesiologists. MATERIAL AND METHOD: A questionnaire on the organization of preoperative testing was completed by anesthesiologists at five public hospitals in the Canary Islands. The questionnaire emphasized the most commonly ordered screening procedures, such as chest X-rays, electrocardiograms, laboratory tests and spirometry. RESULTS: Red cell counts were most frequently requested (for 86% of the patients), followed by platelet counts (80%) and blood chemistry (75%) and coagulation studies (72%). Least requested were urine tests and spirometry. The frequencies of electrocardiogram and chest X-ray requests fell between the two extremes, with patient age and the presence of certain indications seeming to affect whether those tests would be ordered or not. The need for such screening was perceived to increase for patients over 40 years of age. The ordering of preoperative tests varied from hospital to hospital and among anesthesiologists at a single site in spite of established protocols. CONCLUSIONS: Hospitals and individual anesthesiologists differ considerably in how they request preoperative tests. The variations can not be explained solely by differing patient needs given that respondents were contemplating only healthy/asymptomatic individuals undergoing relatively simple procedures.  相似文献   
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Sleep apnea and hypertension   总被引:22,自引:0,他引:22  
STUDY OBJECTIVES: To examine the central inspiratory drive response to hypoxia in patients with obstructive sleep apnea (OSA), according to their circadian BP profile, and in healthy control subjects. Another objective was to evaluate the relationships among sleep architecture, hypoxic sensitivity, urinary catecholamine excretion, and BP in OSA patients. PATIENTS AND INTERVENTIONS: Polysomnography, 24-h ambulatory BP recording, and urinary excretion of catecholamines were simultaneously examined in 24 consecutive OSA patients and 11 healthy subjects. OSA patients were categorized as being normotensive (type 1), having BP elevation only during sleep (type 2), and as being hypertensive with elevated BP at all times (type 3). The response of mouth occlusion pressure at 0.1 s after onset (P(0.1)) to progressive isocapnic hypoxic stimulation was measured. RESULTS: There was a significant difference in the P(0.1) response to hypoxia among control subjects ([mean +/- SD] 0.353 +/- 0.129 cm H(2)O/%) and type 1 (0.228 +/- 0.062 cm H(2)O/%), type 2 (0. 345 +/- 0.106 cm H(2)O/%), and type 3 (0.508 +/- 0.118 cm H(2)O/%) OSA patients. In OSA patients, chemosensitivity was related to the apnea-hypopnea index and to the nocturnal excretion of epinephrine. Significant relationships between the nocturnal excretion of epinephrine and BP were noted. On multiple linear regression analysis, the P(0.1) response to hypoxia was the only variable significantly related to diurnal (r(2) = 0.364; p = 0.005) and nocturnal mean BP (r(2) = 0.461; p = 0.002). CONCLUSION: The findings of the present study suggest a possible mediating role of the peripheral chemosensitivity in the association between sleep apnea and hypertension.  相似文献   
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This study suggests that use of embalming fluid as a mind-altering drug has been underreported. Based on a social network recruitment strategy, findings from a study in 2000 of 401 outreach worker-recruited polydrug-involved youth (ages 16-24 years) from the inner city of Hartford, CT indicate widespread (over 80% of study participants had used the drug at least once) and regular use of embalming fluid mixed with either marijuana or mint. This paper reports findings on frequency and distribution of use, experience, and consequences of use, access to the drug, and characteristics of embalming fluid users. Given the toxic substances that comprise embalming fluid, and the tendency, affirmed in the present study, of the drug to be associated with violent behavior, there is a need to recognize embalming fluid as a drug of concern among youth.  相似文献   
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Although some studies suggested a link between exposure to trace elements and development of multiple sclerosis (MS), clear information on their role in the aetiology of MS is still lacking. In this study the concentrations of Al, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, Hg, Li, Mg, Mn, Mo, Ni, Pb, Sb, Si, Sn, Sr, Tl, V, W, Zn and Zr were determined in the blood of 60 patients with MS and 60 controls. Quantifications were performed by inductively coupled plasma (ICP) atomic emission spectrometry and sector field ICP mass spectrometry. When the two groups were compared, an increased level of Co, Cu and Ni and a decrement of Be, Fe, Hg, Mg, Mo, Pb and Zn in blood of patients were observed. In addition, the discriminant analysis pointed out that Cu, Be, Hg, Co and Mo were able to discriminate between MS patients and controls (92.5% of cases correctly classified).  相似文献   
60.
The haematic concentration of 26 metals and the oxidative damage in 60 patients (20 males and 40 females) affected by Alzheimer's disease and 44 healthy individuals (33 males and 11 females) were compared. In patients, the following significant (p < or = 0.05) discrepancies were found: i) increment of Ca, Cd, Hg, Mg, Si and Sn, and decrement of Al, Co, Fe and Zn in serum; ii) higher concentrations of Cu, Li, Mn, Sn and Zr and lower of Fe, Hg, Mo in blood; iii) overproduction of oxidant species (SOS) and decrease of the anti-oxidant capacity (SAC) (p < or = 0.001, for both). Variables that, joined, better discriminated between patients and controls resulted to be Si, SOS, SAC, Co, Ca, Al in serum (94% of cases correctly classified) and Cu, Zr, Mo and Fe in blood (90% of cases properly categorized).  相似文献   
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