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The aim of this study was to evaluate the dental health conditions of male employees in a large aluminum factory. The present report deals only with the periodontal findings. Five percent of the 181 examined subjects between 25 and 60 yr were edentulous, and all dentate individuals had some degree of periodontal disease. Surfaces harboring stainable plaque were high in all age groups, varying between 65 and 85%. Surfaces without retention factors were 31% and decreased with increasing age. The percentage of sites with bleeding increased from about 40% in the lowest to about 60% in the highest age group. Teeth with probing depths greater than or equal to 4 mm increased from about 30% in the age group 25-29 yr to about 45% in the age group 30-34 yr, after which it increased gradually with increasing age. The difference in bone scores (marginal bone loss) was the most extensive between the ages of 25 and 34 yr, but with a significant increase throughout the age groups. The administrators had a somewhat better oral hygiene, fewer retention factors, less bleeding, fewer pockets and some more marginal bone support than the workers. Still, the administrators had more missing teeth than the workers.  相似文献   
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In solid-phase peptide synthesis (SPPS) the growing peptide chain may undergo chain aggregation which can cause serious synthetic problems. A number of investigations concerning this problem have been reported in the chemical literature. During a study of such “difficult sequences” using the Fmoc-protection strategy, we have observed that peptide-chain aggregation may be significantly reduced when certain amino acid sequences are incorporated C-terminally (1). Thus, synthesis of the difficult poly-alanine, (Ala)n, sequence (n ≦ 20) has been investigated with (Lys(Boc))m (m lE; 6) and (Glu(tBu))m (m ≧ 6) as pre-sequences. With m ≧ 3, peptides are obtained as single, homogeneous products while a complex mixture of deletion peptides and corresponding Fmoc-protected peptides is formed (n ≧ 6) without the pre-sequence. A mixed pre-sequence, (Lys(Boc)Glu(tBu))3, has a similar favorable effect on the synthetic results, but the positive effect seems confined to a rather narrow framework of amino acids and side-chain protecting groups in the pre-sequence as discussed in the article. Among other reputedly difficult sequences the synthesis of H-(Thr-Val)5-OH, H-Val-Asn-Val-Asn-Val-Gln-Val-Gln-Val-Asp-OH, the Acyl Carrier Protein (65–74) and the human insulin B-chain has been investigated. In all cases introduction of a pre-sequence gives rise to satisfactory synthetic results. In the latter case, the lysine pre-sequence may be cleaved enzymatically to give the desB30 insulin B-chain. NIR-FT Raman studies of the synthesis of the poly-alanine, (Ala)n, sequences have shown that the pre-sequence (Lys(Boc))6 shifts the conformation of the growing peptide chain from a β-structure (n ≧ 6) to a random coil conformation (1c). This result is in agreement with the general observation that SPPS proceeds optimally under random coil conditions.  相似文献   
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María Padilla  Elisabeth Coll  Cristina Fernández-Pérez  Teresa Pont  Ángel Ruiz  Marina Pérez-Redondo  Eva Oliver  Lander Atutxa  José M. Manciño  Domingo Daga  Eduardo Miñambres  José Moya  Bárbara Vidal  José M. Dueñas-Jurado  Fernando Mosteiro  Alberto Rodríguez-Salgado  Esperanza Fernández-García  Ramón Lara  Domingo Hernández-Marrero  Belén Estébanez  María Luisa Rodríguez-Ferrero  María Barber  Fernando García-López  Amado Andrés  Carlos Santiago  Ana Zapatero  Rafael Badenes  Francisco Carrizosa  José J. Blanco  José L. Bernal  Francisco J. Elola  Cristina Vidal  Christel Terrón  Pablo Castro  Jordi Comas  Beatriz Domínguez-Gil 《American journal of transplantation》2021,21(11):3618-3628
Normothermic regional perfusion (NRP) allows the in situ perfusion of organs with oxygenated blood in donation after the circulatory determination of death (DCDD). We aimed at evaluating the impact of NRP on the short-term outcomes of kidney transplants in controlled DCDD (cDCDD). This is a multicenter, nationwide, retrospective study comparing cDCDD kidneys obtained with NRP versus the standard rapid recovery (RR) technique. During 2012–2018, 2302 cDCDD adult kidney transplants were performed in Spain using NRP (n = 865) or RR (n = 1437). The study groups differed in donor and recipient age, warm, and cold ischemic time and use of ex situ machine perfusion. Transplants in the NRP group were more frequently performed in high-volume centers (≥90 transplants/year). Through matching by propensity score, two cohorts with a total of 770 patients were obtained. After the matching, no statistically significant differences were observed between the groups in terms of primary nonfunction (p = .261) and mortality at 1 year (p =  .111). However, the RR of kidneys was associated with a significantly increased odds of delayed graft function (OR 1.97 [95% CI 1.43–2.72]; p < .001) and 1-year graft loss (OR 1.77 [95% CI 1.01–3.17]; p = .034). In conclusion, compared with RR, NRP appears to improve the short-term outcomes of cDCDD kidney transplants.  相似文献   
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Coexisting bicuspid aortic and pulmonary valves is an extremely rare condition, and there have been few published cases. Diagnosis of bicuspid aortic valve is straightforward with 2D echocardiography; however, analysis of the morphology of the pulmonary valve is challenging. In this study, we report on a case of a 32‐year‐old man with bicuspid aortic and pulmonary valves diagnosed by 2D and 3D transthoracic echocardiography. The enlarged pulmonary artery without any obvious etiology led us to suspect a pulmonary valve anomaly; thus, we comprehensively evaluated it with 2D and 3D echocardiography, which confirmed the diagnosis of bicuspid pulmonary valve.  相似文献   
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