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81.
Venous ulcers are the most common form of leg ulcers, which induce lesion because of the loss of substances deposited on the damaged skin. Isosorbide dinitrate is a vasodilator with effects on both arteries and veins and induces opening of vascular layers. The objective is to study the effects of isosorbide dinitrate-spray in patients with chronic venous ulcers. Forty-five patients of both sexes with chronic venous ulcers were randomized to receive isosorbide dinitrate or placebo sprays daily for 3 months. The ulcers were measured and clinical characteristics were taken every 15 days during the treatment. Patients treated with isosorbide dinitrate showed an improvement of the ulcerated area (71.29%) compared with patients treated with placebo (54.35%). The histopathological study indicated an increment in the number of hypertrophic and hyperplasic capillaries. Macroscopically, the isosorbide dinitrate-treatment showed the best results, but it was only during the first 6 weeks of treatment. Patients with chronic venous ulcer receiving isosorbide dinitrate spray showed improvement.  相似文献   
82.
Serum leptin levels in women with systemic lupus erythematosus   总被引:10,自引:0,他引:10  
The purpose of this study was to evaluate serum leptin levels in systemic lupus erythematosus (SLE). Forty-one women with SLE were compared with 23 healthy women of similar age and body mass index (BMI). Clinical characteristics and Mexican systemic lupus erythematosus disease activity index (Mex-SLEDAI) score were assessed. Serum leptin levels (ng/dl) were measured by enzyme-linked immunosorbent assay (ELISA). Comparisons of leptin levels were made with the Mann-Whitney U-test. In a multiple regression analysis, those factors that could influence the leptin levels were adjusted. Patients with SLE had higher leptin levels than the control group (SLE median 31 vs control median 15, P=0.023). After adjusting by other variables, the serum leptin levels remained higher in SLE than in controls (P=0.02). Patients with SLE had no association between leptin levels and Mex-SLEDAI score, age, duration of disease, or prednisone doses. Those with SLE had higher leptin levels than controls. Further longitudinal studies are required to evaluate the role of this hormone in the exacerbations of SLE.  相似文献   
83.

Introduction and Aims

Shorter patient delays are associated with a better prognosis for patients diagnosed with ST-segment elevation myocardial infarction (STEMI). This study aimed to identify predictors of patient delay in the Portuguese population.

Methods

Data on 994 patients with suspected STEMI of less than 12 hours’ duration and referred for primary percutaneous coronary intervention (pPCI) and admitted to 18 Portuguese interventional cardiology centers were collected for a one-month period every year from 2011 to 2015. Univariate and multivariate linear regression models were used to identify predictors of patient delay.

Results

No significant differences were observed in patient delay over the course of the survey. The multivariate analysis identified five predictors of patient delay: age ≥75 years (exp[beta] 1.28; 95% CI 1.10-1.50; p=0.001), symptom onset between 0:00 and 8:00 a.m. (exp[beta] 1.26; 95% CI 1.10-1.45; p=0.001), and attending a primary care unit before first medical contact (exp[beta] 1.75; 95% CI 1.41-2.16; p<0.001) predicted longer patient delay, while calling the national medical emergency number (112) (exp[beta] 0.84; 95% CI 0.71-1.00; p=0.045) and transport by the emergency medical services to the pPCI facility (exp[beta] 0.71; 95% CI 0.59-0.84; p<0.001) predicted shorter patient delay.

Conclusions

We identified five factors predicting patient delay, which will help in planning interventions to reduce patient delays and to improve the outcome of patients with STEMI.  相似文献   
84.
85.
Four genetic polymorphisms located at the promoter (C-257T) and coding regions of CFH gene (exon 2 G257A, exon 14 A2089G and exon 19 G2881T) were investigated in 121 dengue patients (DENV-3) in order to assess the relationship between allele/haplotypes variants and clinical outcomes. A statistical value was found between the CFH-257T allele (TT/TC genotypes) and reduced susceptibility to severe dengue (SD). Statistical associations indicate that individuals bearing a T allele presented significantly higher protein levels in plasma. The −257T variant is located within a NF-κB binding site, suggesting that this variant might have effect on the ability of the CFH gene to respond to signals via the NF-κB pathway. The G257A allelic variant showed significant protection against severe dengue. When CFH haplotypes effect was considered, the ancestral CG/CG promoter-exon 2 SNP genotype showed significant risk to SD either in a general comparison (ancestral × all variant genotypes), as well as in individual genotypes comparison (ancestral × each variant genotype), where the most prevalent effect was observed in the CG/CG × CA/TG comparison. These findings support the involvement of −257T, 257A allele variants and haplotypes on severe dengue phenotype protection, related with high basal CFH expression.  相似文献   
86.
Activating and inhibitory killer immunoglobulin‐like receptors (KIR) and their ligands HLA‐Bw4 (loci A and B) were studied by way of establishing whether they can contribute to protection against HIV‐1 infection in highly exposed and persistently seronegative (HESN) patients. Twenty‐three HIV‐1 serodiscordant heterosexual couples, 100 HIV‐1+ patients and 200 healthy individuals were included in this retrospective case–control study. HLA typing was performed by means of PCR followed by sequence‐specific oligonucleotide probe reverse hybridization. KIR3DL1 and KIR3DS1 were studied by PCR sequence‐specific primers. The frequency of KIR3DS1(3DS1/3DL1)‐Bw4 combination was significantly higher in HESN patients versus the discordant couples (P = 0·0003) and HIV‐1+ patients (P = 0·0001). Conversely, the KIR3DL1/KIR3DL1 homozygosity was significantly decreased in HESN patients versus the discordant couples (P = 0·00003), and HIV‐1+ patients (P = 0·00066). The frequency of HLA‐A*32 and HLA‐B*44 was higher in HESN versus their discordant couples (P = 0·009; P = 0·049), and HIV‐1+ patients (P = 0·00002; P = 0·0001). This had greater significance in combination with KIR3DS1 (3DS1/3DL1). KIR3DS1(3DS1/3DL1) could have a greater effect on protection against HIV‐1 infection in HESN patients when bound to a specific HLA allele, in this case HLA‐A*32 and HLA‐B*44, both Bw4 alleles. The differences probably arise both in the HLA alleles and in the subtypes of KIR receptors depending on the ethnic group studied.  相似文献   
87.
88.
The taxonomic affiliations of nineteen root-nodule bacteria isolated from the common bean (Phaseolus vulgaris L.) in Mexico, Ecuador and Brazil were investigated by analyses of 16S rRNA and of four protein-coding housekeeping genes. One strain from Mexico could be assigned to Rhizobium etli and two from Brazil to Rhizobium leucaenae, whereas another from Mexico corresponded to a recently described bean-nodulating species-level lineage related to R. etli and Rhizobium phaseoli. Ten strains isolated in Ecuador and Mexico corresponded to three novel Rhizobium lineages that fall into the R. phaseoli/R. etli/Rhizobium leguminosarum clade. One of those lineages, with representatives isolated mostly from Ecuador, seems to be dominant in beans from that Andean region. Only one of the Mexican strains clustered within the Rhizobium tropici clade, but as an independent lineage. Interestingly, four strains were affiliated with species within the Rhizobium radiobacter clade. The existence of yet non-described native Rhizobium lineages in both the Andean and Mesoamerican areas is discussed in relation to common-bean diversity and environmental conditions.  相似文献   
89.
90.
ObjectiveDespite the increased use of monolithic crowns, their performance has yet to be determined when the minimal tooth preparation (MTP) principle is considered. The goal of this study was to evaluate the effect of MTP on the mechanical behavior, reliability and translucency of posterior monolithic ceramic crowns.MethodsDentin analogues were machined using two preparation designs (0.5 or 1 mm reduction) to receive first molar crowns in order to evaluate the monolithic crown performance. Next, 126 crowns were divided (21/g) according to the material (High translucent zirconia – YZHT, Zirconia reinforced lithium silicate – ZLS and Hybrid ceramic – HC) and thickness (0.5 or 1 mm). Tensile stress concentration was calculated using the finite element method. The crowns were adhesivelly cemented and step stress fatigued to calculate reliability for missions at 600 and 1000 N. Translucency was analyzed in 10 discs of each material and thickness.ResultsHigher stress concentration was found in thinner crowns and those with higher elastic modulus. YZHT crowns were suspended when fatigue reached 1500 N load, thus 1-parameter Weibull was used to analyze the data. Reliability was only affected by thickness at 1000 N. ZLS.5 showed lower survival than HC.5, which was similar to the groups that presented 100% survival. YZHT showed the highest strength and data scattering. ZLS1 (22.3 ± 1.4) presented higher translucency than HC1 (19.2 ± 0.6) and YZHT1 (12.0 ± 2.9), whereas ZLS.5 and HC.5 were similar to each other (26.5 ± 2.3, 26.7 ± 2.2) and superior to YZHT.5 (12.7 ± 1.2).SignificanceHC.5 combined high reliability and translucency with low stress concentration, yielding better crown performance and tooth preservation.  相似文献   
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