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41.
Melasma represents a pigmentary disorder that is difficult to treat. This study aims to broadly review the use of ablative lasers (Er:YAG and CO2) in the treatment of melasma, presenting the level of evidence of studies published to date. A total of 75 patients were enrolled in four case series studies (n=39), one controlled clinical trial (n=6) and one randomized controlled clinical trial (n=30). Studies on the Er:YAG laser showed better results with the use of short square-shaped pulses, which determined low rates of post-inflammatory hyperpigmentation and long-lasting maintenance of results. Likewise, studies on the CO2 laser proved the benefits of short pulse duration along with low-density energy. Post-treatment maintenance with the use of antipigmenting creams was necessary and effective to sustain long-term results. Ablative lasers may represent another useful and effective tool against melasma. Postinflammatory hyperpigmentation and difficulty in sustaining long-term results still represent the main limitations to a broader use of ablative lasers. Based on actual evidence, the use of this technology should be restricted to patients with recalcitrant disease. Further studies will help establish optimal laser parameters and treatment regimens.  相似文献   
42.
Idiopathic Atrophoderma of Pasini and Pierini (IAPP) is a rare, exclusively cutaneous disease. It is more frequent in females, with incidence peak in the second and third decades of life. The etiopathogenesis remains unknown. IAPP most commonly affects the back, abdomen and proximal regions of the limbs. Lesions may be rounded, oval or circular; single or multiple. The evolution is variable and the course is initially progressive. Collagen changes such as atrophy, thinning, condensation and sclerosis may be observed in the papillary dermis. This paper describes a case of Idiopathic Atrophoderma of Pasini and Pierini with histopathologic findings.  相似文献   
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Social context plays a significant role in adolescent identity development, particularly for youth lacking traditional systems of support. Using ecological and symbolic interactionism perspectives, this study qualitatively explored the psychosocial identity development of Black gay, bisexual, or transgendered youth participating in the House Ball Community (HBC). The HBC is a diverse network of family-like structures called ‘houses’, as well as a glamorous social outlet via pageant-like ‘balls’ in which participants compete. A series of focus groups were conducted with youth and leaders from the HBC (n?=?37; age range?=?17–24). Via cross-case and comparative analyses, specific motivating factors related to entry into and continued involvement in the community were identified. Factors related to entry into the community included lack of safe spaces, opportunities for acceptance, means of subsistence, and allure of the scene. Factors related to continued involvement included resilience and coping skills development, sexual identity acceptance and pride, prevalence of risky behaviour, and risk of exploitation. Discussion of these factors provides insight on how self-constructed, supplementary social contexts may provide both unique supports and risks to members, allowing for more focused and well-informed interventions and policies to enhance healthy development in such communities while mitigating risk.  相似文献   
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The aim of this systematic review was to test the following hypotheses: (1) that there is no difference in implant survival rate between individuals with overweight or obesity and those who are within the ideal weight range; (2) that there are no differences between these groups regarding indicators of peri-implant health. Two independent reviewers performed a literature search of the PubMed/MEDLINE, Scopus, and Cochrane Library databases for studies published up to April 1, 2018. A meta-analysis was performed to determine the risk difference for implant failure and mean difference for marginal bone loss, probing depth, and bleeding on probing. Six studies were selected for review, involving a total of 746 patients with 986 implants: 609 in overweight or obese individuals and 377 in individuals within the ideal weight range. The findings of this systematic review indicate that the first hypothesis should be accepted, since no statistically significant difference in implant survival rate was found between individuals with overweight/obesity and those within the ideal weight range (P = 0.64). The second hypothesis was rejected, as the review indicated a difference in marginal bone loss (P < 0.00001), probing depth (P < 0.00001), and bleeding around dental implants (P < 0.00001).  相似文献   
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目的 探讨家庭群居爆发型新型冠状病毒肺炎(简称"新冠肺炎")(novel coronavirus pneumonia,NCP)的临床与胸部HRCT表现特点。方法 收集2020年2月3所医院经核酸检测阳性确诊的新冠肺炎患者10例(4个家庭),其中男性6例(中位年龄60.5岁),女性4例(中位年龄59岁)。所有患者均接受胸部CT扫描并行薄层HRCT重建,由两名10年以上工作经验放射科医生共同阅片分析新冠肺炎HRCT病变发生部位、形态、分布、密度等特点,以及治疗前后HRCT征象变化。并收集临床和实验室指标进行分析和总结。结果 本组4个家庭中首例确诊病例均有武汉确诊病例或武汉疫区接触史,4例为输入型病例(占40%),平均潜伏期5 d。实验室检查中5例(50%)外周血白细胞总数降低,4例(40%)淋巴细胞明显降低;8例(80%)C-反应蛋白增高,10例(100%)乳酸脱氢酶增高。10例(100%)患者胸部CT均有阳性表现,其中7例(70%)表现为双肺散在分布磨玻璃密度影(ground glass opacity,GGO),病变界限大多清楚。8例(80%)累及多个肺叶,2例(20%)为单肺叶病变。绝大多数病灶位于胸膜下和肺外周处,以双肺下叶为著。5例患者(50%)病变内可见细支气管充气征,9例患者(90%)病变内可见增粗细小血管影。7例患者(70%)治疗后复查胸部CT,3例(30%)原肺内胸膜下病变出现不同程度实变及纤维化,2例(20%)实变影转变为GGO,1例(10%)原肺内GGO消失,又出现新发GGO,1例(10%)病变范围有增大。结论 新冠肺炎具有家庭群居爆发的特点,均可有输入性病例,潜伏期较短,其胸部HRCT表现具有一定特征性,且有助于治疗后患者病变动态观察;结合流行病学和实验室检查有助于对NCP做出临床诊断和提供疫情防控的可靠依据。  相似文献   
49.
Abstract

During pulmonary rehabilitation, a subset of subjects with COPD requires adjunct therapy to achieve high-intensity training. Both noninvasive ventilation (NIV) and inspiratory muscle training (IMT) are available to assist these subjects. We aimed to prime the respiratory muscles before NIV with IMT, anticipating additive effects for maximal exercise tolerance (T lim) and dyspnea/leg fatigue relief throughout the exercise as primary outcomes. Changes in the respiratory pattern were secondary outcomes. COPD subjects performed a total of four identical constant work rate tests on a cycle ergometer at 75% of maximum work rate, under control ventilation (SHAM, 4?cm H2O) or proportional assisted ventilation (PAV, individually adjusted), before and after 10 sessions of high-intensity IMT (three times/week) during 30?days. Two-way RM ANOVA with appropriate corrections were performed. Final analysis in nine subjects showed improved T lim (Δ = 111?s) and lower minute-ventilation (Δ = 4?L.min?1) at exhaustion, when comparing the IMT effects within the PAV modality (p?=?0.001 and p?=?0.036, respectively) and improved T lim for PAV vs. SHAM (PAV main-effect, p?=?0.001; IMT main-effect, p?=?0.006; PAV vs. IMT interaction, p?=?0.034). In addition, IMT?+?PAV association, compared to PAV alone, resulted in lower respiratory frequency (IMT main-effect, p?=?0.009; time main-effect, p?<?0.0001; IMT vs. time interaction, p?=?0.242) and lower inspiratory time related to duty cycle (IMT main-effect, p?=?0.018; time main-effect, p?=?0.0001; IMT vs. time interaction, p?=?0.004) throughout exercise. The addition of IMT prior to a PAV-supported aerobic bout potentiates exercise tolerance and dyspnea relief and induces favourable changes in ventilatory pattern in severe COPD during high-intensity training (Brazilian Registry of Clinical Trials, number RBR-6n3dzz).  相似文献   
50.
Splinted and unsplinted overdenture attachment systems have unique advantages and disadvantages. The aim of the present systematic review was to determine the influence of splinted and unsplinted overdenture attachment systems on the marginal bone loss, prosthetic complications and implant survival rate. PubMed/MEDLINE , Scopus and Cochrane databases were searched for articles published up to October 2017, using the following search terms: “overdenture AND attachment OR overdenture AND bar OR overdenture splinted.” The PICO question “Do splinted overdenture attachment systems promote better clinical results in comparison to unsplinted systems?” was evaluated. Eligible studies included randomized controlled clinical trials, prospective studies with at least 10 participants and a minimum follow‐up of 6 months, and studies published in English that compared splinted and unsplinted attachment systems within the same study. The 95% confidence interval (CI ) was considered for all outcomes analysed. After completion of the different steps in the article selection process, nine articles were included in the qualitative and quantitative analyses. A total of 984 implants were placed in 380 patients (mean age: 62.8 years). The meta‐analysis demonstrated no statistically significant differences between splinted and unsplinted attachment systems with regard to marginal bone loss (P  = .39; MD : ?0.11; 95% CI : ?0.37 to 0.14), complications (P  = .31; RR : 1.26; CI : 0.80‐1.99) and implant survival rate (P  = .14; RR : 0.37% CI : 0.10‐1.36). In addition, splinted and unsplinted overdenture attachment systems achieved similar results with regard to marginal bone loss, prosthetic complications and implant survival rate.  相似文献   
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