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111.
The ALAT and SEPAR Treatment and Control of Smoking Groups have collaborated in the preparation of this document which attempts to answer, by way of PICO methodology, different questions on health interventions for helping COPD patients to stop smoking.The main recommendations are: (i) moderate-quality evidence and strong recommendation for performing spirometry in COPD patients and in smokers with a high risk of developing the disease, as a motivational tool (particularly for showing evidence of lung age), a diagnostic tool, and for active case-finding; (ii) high-quality evidence and strong recommendation for using intensive dedicated behavioral counselling and drug treatment for helping COPD patients to stop smoking; (iii) high-quality evidence and strong recommendation for initiating interventions for helping COPD patients to stop smoking during hospitalization with improvement when the intervention is prolonged after discharge, and (iv) high-quality evidence and strong recommendation for funding treatment of smoking in COPD patients, in view of the impact on health and health economics.  相似文献   
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The clinical use of pulsed electromagnetic fields (PEMF) in osteoarticular pathology is widely extended, although the mechanisms involved are unknown. The aim of this study was to evaluate the action of a new protocol of treatment with PEMF on liquid medium cultures of fibroblast-like cells derivates of mononuclear peripheral blood cells. Fibroblast-like cells growth was obtained in liquid medium culture from mononuclear cells (MNC) of human peripheral blood. The PEMF irradiation protocol included an intensity of 2.25 mT, a frequency of 50 Hz and an application time of 15 min on days 7, 8 and 9 of cell culture. Immunophenotype was performed with specific heterologous monoclonal antibodies for each cell receptor (Vimentin, Cytokeratin, CD34, CD41, CD61 and CD68). The cytokines’ production was determined in the supernatant of the culture medium by means of the Luminex technology. The immunophenotype did not show any statistical difference on comparing treated against non-treated cell cultures on any of the days. In the treatment cell population, the proinflammatory cytokines, IL-1β and TNF-α showed a significant decrease on days 14 and 21 of the culture, whilst IL-10 increased significantly on day 21. It is concluded that PEMF irradiation does not alter the cell immunophenotype of the fibroblast-like cell population, but does provoke a decrease in the production of inflammatory-type cytokines (IL-1β, TNF-α) and an increase in cytokines of lymphocytic origin (IL-10). These facts coincide with the chronology of the clinical effect undergone by patients with osteoarticular pathology after PEMF irradiation.  相似文献   
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To attend successfully, a specification of what is currently relevant is necessary, but not sufficient. Irrelevant stimuli that are also present in the environment must be recognized as such and filtered out at the same time. Using functional magnetic resonance imaging, we showed that posterior brain regions in parietal, occipital and temporal cortex are recruited in order to ignore distracting visual stimuli, while the specification and selection of relevant stimuli is associated with differential activity in frontal cortex and hippocampal areas instead. The results thus suggest that the selection of relevant objects can be anatomically dissociated from the handling of competing irrelevant objects. The dissociation between the increased involvement of parietal and occipital cortex in handling distraction on one hand, and that of frontal cortex in target specification on the other provides neurophysiological support for models of attention that make this functional distinction.  相似文献   
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PURPOSE: Despite having removed the whole macroscopic disease (curative intent surgery), one of five patients with Stages I and II colorectal cancer will develop recurrence. Lymphatic micrometastases detected by immunohistochemistry could be one of explanation for recurrence and cancer-related death in patients without lymph node involvement at light microscopy. However, the biologic importance of micrometastases remains unclear. This study was designed to determine the impact of micrometastases in five-year survival in patients with Stages I and II colorectal cancer.METHODS: This retrospective study included patients operated on between May 1989 and January 1999 for colorectal cancer without histopathologic lymph node involvement. Patients who received any adjuvant therapy were excluded. Immunohistochemical staining of the lymph nodes was performed with antipancytokeratin antibodies. Follow-up data were obtained from the clinical database and death certificates. Survival was estimated by the Kaplan-Meier method and compared by the log-rank test.RESULTS: Micrometastases were observed in 26 of 90 patients (28.9 percent). The mean follow-up time was 90.7 (range, 11–160) months. Seventeen cancer-related deaths occurred during follow-up (18.9 percent), 6 of them in patients with micrometastases (23.1 percent) and 11 in patients without micrometastases (17.2 percent; P = 0.559). Cancer-specific five-year survival was 87 percent in the whole group and 81 percent in patients positive for micrometastases vs. 90 percent in negative patients (P = 0.489).CONCLUSIONS: The presence of micrometastases in patients with Stages I and II colorectal cancer seems not to have any impact on cancer-specific survival.Supported by the Apertus Research Program (Andromaco Pharmaceutical Company) and by The National Public Grant (FONDECYT #1000556).  相似文献   
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INTRODUCTION: The causes of cardiac tamponade vary and it has been suggested that underlying causes should be sought in all cases. The purpose of this study was to determine the causes of cardiac tamponade in our environment, distinguishing between specific and idiopathic causes, and analyzing the proportion and causes in the subgroup of patients with relapsing tamponade. PATIENTS AND METHOD: We retrospectively studied all patients who underwent therapeutic pericardiocentesis between 1985 and 2001. The clinical and radiographic features and macroscopic characteristics of the pericardial fluid were analyzed. The final diagnosis in each patient was based on the clinical history, follow-up, pericardial fluid cytology, and pericardial biopsy, if available. RESULTS: Ninety-six patients were included (52 men/44 women), mean age 56.1 16.1 years. The cause of pericardial effusion was neoplasm in 50 patients (52.1%), 14 idiopathic pericarditis (14.6%), 12 renal failure (12.5%), 7 iatrogenic cases (7.3%), 4 mechanical tamponades (4.2%), 2 tuberculosis (2.1%), and 7 other causes (7.3%). Thirty-five patients had relapsing tamponade; only 2 of them had idiopathic pericarditis (5.7%). We found no significant differences in age, development time, extracted volume or fluid features between tamponade of specific or idiopathic origin. CONCLUSIONS: Most of the cardiac tamponades in our series had a specific cause. This made it necessary to identify a specific underlying cause in each case, especially in relapsing effusions. However, we did not find any variable suggestive of the cause of the disease.  相似文献   
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Melanopsin is the photopigment that confers light sensitivity on intrinsically photosensitive retinal ganglion cells. Mammalian intrinsically photosensitive retinal ganglion cells are involved in the photic synchronization of circadian rhythms to the day-night cycle. Here, we report molecular components of melanopsin signaling using the cultured Xenopus dermal melanophore system. Photo-activated melanopsin is shown to initiate a phosphoinositide signaling pathway similar to that found in invertebrate photo-transduction. In melanophores, light increases the intracellular level of inositol trisphosphate and causes the dispersion of melanosomes. Inhibition of phospholipase C and protein kinase C and chelation of intracellular calcium block the effect of light on melanophores. At least four proteins, 43, 74, 90, and 134 kDa, are phosphorylated by protein kinase C upon light stimulation. This provides evidence of an invertebrate-like light-activated signaling cascade within vertebrate cells.  相似文献   
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The optimal planning of preoperative diagnosis, management and treatment of pituitary tumors (PT) candidates to pituitary surgery (PS) requires a multidisciplinary approach involving a team of endocrinologists, neurosurgeons, ENT, neuro-ophthalmologists and neuroradiologists with experience in pituitary diseases. Such teams improve surgical results, minimize complications and facilitate their correct treatment if occurring, and optimize the hormonal, ophthalmological and radiological preoperative and follow-up evaluation. We have developed a clinical practice protocol for patients with PT who are candidates to PS based on the most recent national and international guidelines and the relevant literature regarding PT published in the last years. The protocol has been elaborated by a multidisciplinary team of a Spanish Pituitary Tumor Center of Excellence (PTCE) that includes at least one neurosurgeon, ENT, neuroradiologist, neuro-ophthalmologist, endocrine pathologist and endocrinologist specialized in pituitary diseases. We elaborated this guideline with the aim of sharing our experience with other centers involved in the perioperative and surgical management of PT thereby facilitating the management of patients undergoing PS.  相似文献   
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