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In this report, we describe an investigation of the effects of Lutzomyia longipalpis sand fly salivary gland homogenates (SGH) on cytokine production and expression of costimulatory molecules on human monocytes, macrophages (Ms), and dendritic cells (DCs). SGH of L. longipalpis induced an increase in interleukin-6 (IL-6), IL-8 and IL-12p40 production but a decrease in tumor necrosis factor alpha and IL-10 production by lipopolysaccharida (LPS)-stimulated monocytes. We also examined the expression of costimulatory molecules on the surface of monocytes, Ms, and DCs. Whereas SGH affected the expression of these molecules on monocytes and Ms, it had little effect on these molecules on DCs. However, when DCs were generated from human monocytes in the presence of SGH, SGH inhibited the expression of costimulatory molecules. In addition, a decrease in the maturation of DCs induced by CD40L was observed in the presence of SGH. Finally, preincubating SGH with human sera containing anti-SGH-specific antibodies abolished the effects of SGH on cytokine production by LPS-stimulated monocytes.  相似文献   
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This cross-sectional study is aimed at the identification of patterns in the utilization of health care services in Pau da Lima, a neighborhood in the city of Salvador, Bahia. In 1992, a household survey was carried out with 384 families selected through a random cluster sampling design. In each household, the family head or a surrogate informant was asked to answer a questionnaire about their use of any type of health care in the last month. From the total of 1,887 individuals, 236 reported at least one visit to health facilities during the referent period This means an estimated prevalence of health services utilization of 12.5%. With regard to the type of services, 25.9% of all visits were made to public sector facilities. Attendants were mainly women (73.7%) from 15 to 29 years of age. The main reason reported for the choice of the health facility was availability (63.7%), and the major reason for seeking health care was disease-related conditions (75.7%), rather than preventive procedures. These findings may result from the still unfinished process of distritaliza??o(district allocation of services), which is evident in the lack of health services' infrastructure or coverage, as well as in persistent organizational problems. These issues may lead the population living in the respective district to seek health care outside the assigned catchment area. The authors discuss these findings in the context of the expansion of the private sector in the health area and the financial collapse of the public budget in Brazil.  相似文献   
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Novel imaging techniques for diabetic macular edema   总被引:2,自引:0,他引:2  
Retinal edema should be defined as any increase of water of the retinal tissue resulting in an increase in its volume. It may be of cytotoxic or vasogenic origin. Development of vasogenic macular edema is dependent on a series of factors such as blood pressure, blood-retinal barrier permeability, retinal cell damage, retinal tissue osmotic pressure and retinal tissue compliance. Objective measurements of retinal thickness are now possible using the Retinal Thickness Analyser. Localised measurements of blood-retinal barrier permeability may also be obtained using the Retinal Leakage Analyser, a modified confocal scanning laser fluorometer, while obtaining simultaneously angiographic images of the choroid and retina. These new imaging techniques show that cytotoxic and vasogenic retinal edema may occur independently in the early stages of diabetic retinopathy. These findings offer new perpectives for designing novel therapeutic strategies. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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OBJECTIVES: To assess the feasibility and safety of non invasive positive-pressure ventilation (NIPPV) via a face mask to performing fiberoptic bronchoscopy (FOB) in patients with COPD contraindicating FOB in spontaneous ventilation. STUDY DESIGN: Clinical, prospective, open, non comparative trial of feasibility. PATIENTS: Ten consecutive COPD patients (71 +/- 5 year-old, PaO2 = 53 +/- 13 mmHg and PaCO2 = 67 +/- 11 mmHg), without any sign of acute respiratory failure, admitted to the intensive care unit for pneumonia requiring a bronchoalveolar lavage (BAL). Including were: PaO2 < 70 mmHg despite nasal O2 delivered at 3 L.min-1, PaCO2 > 50 mmHg, improvement of SpO2 with NIPPV before FOB. METHODS: Topical anaesthesia of the nose and pharynx was obtained with a 5% lidocaine spray. NIPPV was administered using a ventilatory support system Evita 4 (Dr?ger) applied through a full facial mask secured to the patient with elastic straps. Patients were first allowed to acclimate for 5 min with NIPPV (IPAP = 16 cmH2O, EPAP = 0 and trigger of 0.3 cm H2O while a FIO2 kept at 0.7). A T-adapter Medisize (Péters) was attached to the facial mask. The tip of the FOB was inserted through the nose. Topical anaesthesia of the vocal cords was obtained with 1% lidocaine solution (3 mL). The FOB was inserted into the trachea up to a bronchial sub-segment. BAL was performed by instillation of 100 mL of saline solution. After FOB, the NIPPV was maintained for 5 min. Heart rate, SpO2 were measured continuously and arterial pressure at 2 min intervals. Arterial blood gas values were obtained just prior NIPPV and after 15 min and 60 min NIPPV disconnection. RESULTS: FOB duration was 11 +/- 4 min. SpO2 significantly improved during FOB (from de 91 +/- 4.7% to 97% +/- 1.7) without decrease of oxygen saturation lower than 90%. There were no changes in PaCO2 and PaO2 during the hour following the end of procedure. FOB under NIPPV was performed in all patients without complications and was very well tolerated in eight patients. After NPPV disconnecting, one patient required again NIPPV for 15 min. No patient required endotracheal intubation within 24 hours. All patients survived. CONCLUSION: Application of NIPPV during FOB is a safe technic for maintaining adequate gas exchange in hypoxaemic and hypercapnic COPD patients not in acute respiratory failure. After the end of the procedure a close surveillance in the intensive care unit is essential.  相似文献   
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Parasitology Research - Phthalimide, 1,3-thiazole, and thiazolidinone cores are considered privileged scaffolds and represent an attractive starting point to design new bioactive compounds for...  相似文献   
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