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61.
Neurological Sciences - Alzheimer’s disease (AD) diagnosis can be hindered by amyloid biomarkers discordances. We aim to interpret discordances between amyloid positron emission tomography...  相似文献   
62.
Basal cell carcinoma (BCC) is a common skin cancer worldwide. However, BCC of the nipple and areola complex is rare. Men are more affected than women. Most of the cases were treated with simple excision. We report a case of BCC of the right nipple–areola complex in a 75‐year‐old man, treated with Mohs surgery and simple mastectomy.  相似文献   
63.
Much experimental evidence suggests that an imbalance in cellular redox status is a major factor in the pathogenesis of Alzheimer's disease (AD). Our previous data showed a marked increase in membrane lipoperoxidation in primary fibroblasts from familial AD (FAD) patients. In the present study, we demonstrate that when oligomeric structures of Abeta 1-40 and Abeta 1-42 are added to the culture media, they accumulate quicker near the plasma membrane, and are internalized faster and mostly in APPV717I fibroblasts than in age-matched healthy cells; this results in an earlier and sharper increase in the production of reactive oxygen species (ROS). Higher ROS production leads in turn to an increase in membrane oxidative-injury and significant impairment of cellular antioxidant capacity, giving rise to apoptotic cascade activation and finally to a necrotic outcome. In contrast, healthy fibroblasts appear more resistant to amyloid oxidative-attack, possibly as a result of their plasma membrane integrity and powerful antioxidant capacity. Our data are consistent with increasing evidence that prefibrillar aggregates, compared to mature fibrils, are likely the more toxic species of the peptides. These findings provide compelling evidence that cells bearing increased membrane lipoperoxidation are more susceptible to aggregate toxicity as a result of their reduced ability to counteract amyloid oligomeric attack.  相似文献   
64.

Purpose

Several studies in recent years have investigated the relationship between alcohol intake and melanoma risk, with conflicting results. To help clarify this issue, we conducted a literature review and dose–response meta-analysis of studies published until June 30th, 2017, that examined the association between alcohol intake (overall and by beverage type) and melanoma risk.

Methods

We used random effect models with maximum likelihood estimation to calculate summary relative risk (SRR) and 95% confidence intervals (95%CI).

Results

We included 20 independent studies (encompassing 10,555 melanoma cases and over 1.6 million non-cases/controls) published during 1986–2016, of which six had a prospective cohort study design. Adjustment for phenotypic characteristics and sunlight exposure was performed in 11 and nine studies, respectively. Alcohol intake was moderately associated with melanoma risk: the SRR were 1.29 (95% CI 1.14–1.45) for those in the highest vs. lowest category of current alcohol intake, and 1.96 (95% CI 1.02–3.76, I2?=?0%) for cumulative intake. In the dose–response analysis, the increase in risk associated with a 10 g increment in daily alcohol intake was 1.07 (95% CI 1.03–1.11). Risk estimates did not differ by gender, study design and adjustment for confounders; between-studies heterogeneity was acceptable, and there was no evidence of publication bias.

Conclusions

Our findings suggest that alcohol drinking may be moderately associated with increased melanoma risk, although residual confounding and bias cannot be ruled out. Further research is needed to confirm these findings, clarify the role of the different alcohol sources, and investigate the interaction with known melanoma risk factors.
  相似文献   
65.
Myocardial infarction (MI) occurs more frequently in the morning as a result of the concomitant unfavorable timing of several physiological parameters and/or biochemical conditions. However, little is known about the possible influence of this circadian pattern on prognosis. To evaluate whether the time of symptom onset could potentially influence mortality from acute MI, this prospective study considered all consecutive MIs admitted to the ED of Ferrara, Italy, after a call to the Emergency Coordinating Unit from January 1, 1998, to December 31, 2001. The total sample consisted of 442 MIs (mean age, 68.7 years; males, 72%). Eighty patients (males, 82.5%) died in the ED; the remaining 362 were admitted to the hospital. Of these, 50 (males, 60%) died during their hospital stay. Based on the timing of their symptom onset, cases were categorized both into 24 1-hour intervals and four 6-hour intervals (midnight to 5:59 am, 6:00 am to 11:59 am, noon to 5:59 pm, and 6:00 pm to 11:59 pm), and the circadian distributions of fatal versus nonfatal MIs were compared. The circadian variation of MI peaked between 6:00 am and noon (P < .001), and in this period, there was a trend toward a higher frequency of fatal cases (41.5% vs. 35.2%; chi(2) = 1.911, P = .167). To verify whether this higher frequency of fatal events in the morning hours could be related to possible higher severity of cases observed in that hours, a further separate analysis considering age, infarct site, and peak levels of MB was made. Again, no significant temporal differences among the four 6-hour intervals were found between fatal and nonfatal Mis, although a trend toward older age was observed in morning MIs. Not only the frequency, but also the mortality, of acute MI could be increased in the morning hours. This could be of practical interest for emergency doctors and could have significant implications for acute treatment, because several studies have reported a lowered efficacy of thrombolytic drugs in the morning hours.  相似文献   
66.
Spinel phases, with unique and outstanding physical properties, are attracting a great deal of interest in many fields. In particular, MgFe2O4, a partially inverted spinel phase, could find applications in medicine thanks to the remarkable antibacterial properties attributed to the generation of reactive oxygen species. In this paper, undoped and Ag-doped MgFe2-xAgxO4 (x = 0.1 and 0.3) nanoparticles were prepared using microwave-assisted combustion and sol–gel methods. X-ray powder diffraction, with Rietveld structural refinements combined with micro-Raman spectroscopy, allowed to determine sample purity and the inversion degree of the spinel, passing from about 0.4 to 0.7 when Ag was introduced as dopant. The results are discussed in view of the antibacterial activity towards Escherichia coli and Staphylococcus aureus, representative strains of Gram-negative and Gram-positive bacteria. The sol–gel particles were more efficient towards the chosen bacteria, possibly thanks to the nanometric sizes of metallic silver, which were well distributed in the powders and in the spinel phase, with respect to microwave ones, that, however, acquired antibacterial activity after thermal treatment, probably due to the nucleation of hematite, itself displaying well-known antibacterial properties and which could synergistically act with silver and spinel.  相似文献   
67.
This study aims to assess the efficacy of a universal adhesive (Scotchbond Universal, 3M ESPE) (SB) in total-etch mode, compared to a traditional orthodontic primer (Transbond XT Primer, 3M ESPE) (XT Primer), to perform bonding of orthodontic fixed retainers along with the Transbond XT Light Cure Adhesive Paste (3M ESPE). For the in vitro study, a round section wire (Ortosmail Krugg) was bonded using XT Primer for 20 bovine incisors (Group 1) and SB for other 20 (Group 2). Samples were debonded in a universal testing machine applying a tangential force to specimens (crosshead speed of 1 millimeter per minute). Shear bond strength (SBS) and adhesive remnant index (ARI) scores were calculated. For the in vivo study, 100 patients needing upper and lower canine-to-canine fixed retainers after orthodontic treatment were randomly assigned to two groups of 50 participants each, i.e., group 1 (retainer bonding with XT Primer) and group 2 (retainer bonding with SB). Over two years, examinations were carried out monthly, and detachments were registered by considering the teeth and arches affected. In vitro, no statistically significant differences in SBS and ARI scores were demonstrated between the two groups, both showing a mean bond strength of about 12 MPa and major frequency of ARI “2” (>50% remnant adhesive on the enamel). Conversely, a significantly lower failure rate over 2 years was assessed clinically for group 2 in both arches. Independently of the adhesive and arch, incisors reported a significantly higher failure rate than canines. Scotchbond Universal used in total-etch mode could be a valid alternative to the traditional orthodontic Transbond XT Primer.  相似文献   
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69.
70.

Purpose

Sexual and urinary dysfunctions are complications in radical treatment of deep infiltrating endometriosis (DIE) with colorectal involvement. The aim of this article is to report the preliminary results of our single-institution experience with robotic treatment of DIE, evaluating intraoperative and postoperative surgical outcomes and focusing on the impact of this surgical approach on autonomic functions such as urogenital preservation and sexual well-being.

Methods

From January 2011 through December 2013, a case series of 10 patients underwent robotic radical treatment of DIE with colorectal resection using the da Vinci System. Surgical data were evaluated, together with perioperative urinary and sexual function as assessed by means of self-administered validated questionnaires.

Results

None of the patients reported significant postoperative complications. Questionnaires concerning sexual well-being, urinary function, and impact of symptoms on quality of life demonstrated a slight worsening of all parameters 1 month after surgery, while data were comparable to the preoperative period 1 year after surgery. Dyspareunia was the only exception, as it was significantly improved 12 months after surgery.

Conclusions

Robot-assisted surgery seems to be advantageous in highly complicated procedures where extensive dissection and proper anatomy re-establishment is required, as in DIE with colorectal involvement. Our preliminary results show that robot-assisted surgery could be associated with a low risk of complications and provide good preservation of urinary function and sexual well-being.
  相似文献   
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