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The efficacy and safety of bevantolol (new cardioselective beta-blocking agent without intrinsic sympathetic activity) were evaluated in chronic stable angina pectoris. Acute effects on heart rate (HR) and pulmonary function (forced expiratory volume in the first second, FEV1, and vital capacity, VC) (double-blind placebo, propranolol, 80 mg, and bevantolol, 150 mg) and the antianginal efficacy during early (double-blind placebo period) and chronic bevantolol therapy (long-term follow-up for 52 weeks) were studied. Bevantolol reduces HR in the same way as propranolol (both p less than 0.01). Pulmonary function is modified significantly only by propranolol (decreasing FEV1, p less than 0.05). Bevantolol reduces antianginal attacks and nitroglycerin consumption (p less than 0.01) and improves exercise tolerance (p less than 0.01) during early and chronic therapy.  相似文献   
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BackgroundRecurrent respiratory papillomatosis (RRP) is a respiratory tract disease that affects children and adults and is characterized by the recurrent proliferation of multiple papillomas. The etiologic agent is the human papillomavirus, mainly genotypes 6 and 11. Furthermore, polymorphisms in TAP1 appear to influence the selection of antigenic peptides and the transport process to the rough endoplasmic reticulum, for their subsequent presentation to T lymphocytes, an essential process against viral diseases and tumor processes. Previous studies have shown that individuals with those polymorphisms are susceptible to immune, infectious, and tumor‐related diseases. The present study aimed to determine the association between the TAP1 rs1057141 (c.1177A>G) and rs1135216 (c.2090A>G) single nucleotide polymorphisms (SNPs) and RRP.MethodsA case–control study was carried out on a group of 70 individuals (35 controls and 35 patients). RRP diagnosis, HPV genotyping, and viral load were determined through histology and PCR. SNPs rs1057141 and rs1135216 were identified through allelic discrimination, using real‐time PCR. The haplotypic analyses were performed using the Arlequin 3.5 program.ResultsHPV‐6 and HPV‐11 were the genotypes found in the samples. In the polymorphism analysis, rs1057141 showed no significant differences (p = 0.049, CI = 0.994–7.331). In contrast, a significant difference was found in rs1135216 (p = 0.039, OR = 2.4) in the allelic analysis, as well as in the dominant (p = 0.027, OR = 3.06), codominant (p = 0.033, OR = 3.06), and additive model (p = 0.043, OR = 2.505) in subjects with the G allele.ConclusionThe G allele in rs1135216 was associated with a genetic risk of susceptibility for RRP in a population in Western Mexico.  相似文献   
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Nanotechnology is science, engineering and technology conducted at the nanoscale, which is about 1–100 nm. It has led to the development of nanomaterials, which behave very differently from materials with larger scales and can have a wide range of applications in biomedicine. The physical and chemical properties of materials of such small compounds depend mainly on the size, shape, composition and functionalization of the system. Nanoparticles, carbon nanotubes, liposomes, polymers, dendrimers and nanogels, among others, can be nanoengineeried for controlling all parameters, including their functionalization with ligands, which provide the desired interaction with the immunological system, that is dendritic cell receptors to activate and/or modulate the response, as well as specific IgE, or effector cell receptors. However, undesired issues related to toxicity and hypersensitivity responses can also happen and would need evaluation. There are wide panels of accessible structures, and controlling their physico-chemical properties would permit obtaining safer and more efficient compounds for clinical applications goals, either in diagnosis or treatment. The application of dendrimeric antigens, nanoallergens and nanoparticles in allergy diagnosis is very promising since it can improve sensitivity by increasing specific IgE binding, mimicking carrier proteins or enhancing signal detection. Additionally, in the case of immunotherapy, glycodendrimers, liposomes, polymers and nanoparticles have shown interest, behaving as platforms of allergenic structures, adjuvants or protectors of allergen from degradation or having a depot capacity. Taken together, the application of nanotechnology to allergy shows promising facts facing important goals related to the improvement of diagnosis as well as specific immunotherapy.  相似文献   
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In this prospective, multicentre cohort study, we analysed specific prognostic factors and the impact of timing of highly active antiretroviral therapy (HAART) on disease progression and death among 625 human immunodeficiency virus (HIV)-1-infected, treatment-naïve patients diagnosed with an AIDS-defining disease. HAART was classified as early (<30 days) or late (30–270 days). Deferring HAART was significantly associated with faster progression to a new AIDS-defining event/death overall (p 0.009) and in patients with Pneumocystis jiroveci pneumonia (p 0.017). In the multivariate analysis, deferring HAART was associated with a higher risk of a new AIDS-defining event/death (p 0.002; hazard ratio 1.83; 95% CI 1.25–2.68). Other independent risk factors for poorer outcome were baseline diagnosis of AIDS-defining lymphoma, age >35 years, and low CD4+ count (<50 cells/μL).  相似文献   
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Ductular reactions (DRs) are observed in virtually all forms of human liver disease; however, the histogenesis and function of DRs in liver injury are not entirely understood. It is widely believed that DRs contain bipotential liver progenitor cells (LPCs) that serve as an emergency cell pool to regenerate both cholangiocytes and hepatocytes and may eventually give rise to hepatocellular carcinoma (HCC). Here, we used a murine model that allows highly efficient and specific lineage labeling of the biliary compartment to analyze the histogenesis of DRs and their potential contribution to liver regeneration and carcinogenesis. In multiple experimental and genetic liver injury models, biliary cells were the predominant precursors of DRs but lacked substantial capacity to produce new hepatocytes, even when liver injuries were prolonged up to 12 months. Genetic modulation of NOTCH and/or WNT/β-catenin signaling within lineage-tagged DRs impaired DR expansion but failed to redirect DRs from biliary differentiation toward the hepatocyte lineage. Further, lineage-labeled DRs did not produce tumors in genetic and chemical HCC mouse models. In summary, we found no evidence in our system to support mouse biliary-derived DRs as an LPC pool to replenish hepatocytes in a quantitatively relevant way in injury or evidence that DRs give rise to HCCs.  相似文献   
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