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71.
72.
Cocaine is the most commonly used illicit drug among patients presenting at hospital emergency departments and the most frequent cause of drug-related deaths reported by medical examiners. Various respiratory problems temporally associated with cocaine use have been reported. Acute and chronic uses also are responsible for lung complications, such as pulmonary edema, alveolar hemorrhage, pulmonary hypertension, organizing pneumonia, emphysema, barotrauma, infection, cancer, eosinophilic disease, and aspiration pneumonia. Although most imaging findings are nonspecific, they may raise suspicion of a cocaine-related etiology when considered together with patients’ profiles and medical histories. This literature review describes cocaine-induced diseases with pulmonary involvement, with an emphasis on high-resolution chest computed tomographic findings and patterns.  相似文献   
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Heteropolyacids (HPA) with Keggin structures, such as H3PMo12O40 (H3PMo), have been described as efficient catalysts in trans/esterification reactions due to their tolerance to water and free fatty acids contents, with particularly well-suited characteristics of high proton mobility and stability. The versatile array of HPA is considerably increased when such catalysts are supported onto solid matrices. In this sense, Al2O3 was assessed as support for H3PMo to be used in trans/esterification reactions to produce biodiesel from high-acid feedstocks. The catalyst structure was characterized and applied on trans/esterification reaction of acid oils using ethanol as acyl acceptor. A face centered composite design was employed to conduct the experimental design and results analysis, taking macaw palm oil as study model. The process achieved an optimum level of 99.8% ester content and 4.1 mm2 s−1 viscosity under the following reaction conditions: 190 °C reaction temperature, 50 : 1 ethanol-to-oil molar ratio and 13.0% catalyst concentration. Other tested feedstocks (fungal single cell oil and residual frying oil) were also tested promoting satisfactory results, though the parameters were found to be slightly outside the limits set by the USA (ASTM D6715) standard. The H3PMo/Al2O3 catalyst presented good regeneration and can be reused for up to four reaction cycles and requires lower ethanol-to-oil ratio, temperature, and catalyst concentration in comparison with other data from the literature.

Heteropolyacids (HPA) with Keggin structures, such as H3PMo12O40 (H3PMo), have been described as efficient catalysts in trans/esterifications of high-acid feedstocks due to their tolerance to water and free fatty acids contents.  相似文献   
76.
The aim of the present cross‐sectional study was to assess tobacco use and smoking cessation among third‐year dental students in southern Brazil. The Global Health Professions Student Survey questionnaire was used in eight dental schools in Rio Grande do Sul state, Brazil. Of the 663 eligible students, 576 (87%) participated. The prevalence of current smoking was 19.1% [95% confidence interval (CI): 12.9–25.3%], and 61.6% (95% CI: 54.9–68.3%) of students reported having smoked at least once in their lifetime. The prevalence of dental students who had smoked ≥100 cigarettes in their lifetime was 17.1% (95% CI: 12.5–21.7%). Being frequently exposed to other smokers at home or in other places (second‐hand smoke) increased the likelihood of current smoking by two‐ to threefold. Approximately 6.1% (95% CI: 3.5–8.7%) of the students reported that they currently wanted to stop smoking and 7.5% (95% CI: 5.3–9.6%) had tried to stop smoking in the last year. Friends and family were the most frequent sources of help or counselling, and only a limited proportion of students received help from health professionals. Tobacco use and exposure to second‐hand smoking is widespread among dental students in southern Brazil. Smoking‐cessation initiatives targeting health care students are urgently needed.  相似文献   
77.
Aim:

Low-level laser therapy has still not been well established, and it is important to define a standardized protocol for the treatment of temporomandibular disorders (TMDs) using low level laser. There is no consensus on controlled clinical trials concerning the best option for laser therapy with regard to wavelength. The aim of this study was to evaluate the efficacy of red and infrared laser therapy in patients with TMD, using a randomized parallel-group double-blind trial.

Methodology:

Each hemiface of 19 subjects was randomized to receive intervention, in a total of 116 sensitive points. Pain was measured at baseline and time intervals of 24 hours, 30 days, 90 days, and 180 days after treatment. Irradiation of 4 J/cm2 in the temporomandibular joints and 8 J/cm2 in the muscles was used in three sessions.

Results:

Both treatments had statistically significant results (P<0·001); there was statistical difference between them at 180 days in favor of the infrared laser (P?=?0·039). There was improvement in 24 hours, which extended up to 180 days in both groups.

Conclusion:

Both lasers are effective in the treatment and remission of TMD symptoms.  相似文献   
78.
The novel SARS-CoV-2 virus has led to a severe pandemic, starting from early 2020. Intensive care (ICU) management of the COVID-19 disease is difficult with high morbidity and mortality. Early nutritional support, especially with whey protein, seems to be crucial in this medical case. Thus, we aimed to assess the effects of an adequate nutritional protocol rich in whey protein on nutritional and inflammatory status, extubating time, and mortality of critically ill COVID-19 patients (CICP). Methods: A prospective single-center exploratory observational study was undertaken on 32 consecutive CICP admitted to the ICU of Santa Maria Hospital, Terni, Italy, and treated with whey protein-enriched formula. Patients’ demographics, nutritional status, indexes of inflammation, daily pre-albumin serum levels, duration of mechanical ventilation, and mortality were recorded. Results: Thirty-two patients were enrolled. Ninety-five percent of them showed a gradual reduction in C-reactive protein (CRP) values and increase in pre-albumin levels after the whey protein-enriched formula. Prealbumin levels were not correlated with a better nutritional status but with a shorter extubating time and better survival. Conclusions: An adequate administration of whey protein during COVID-19 patients’ ICU stays can provide fast achievement of protein targets, reducing the duration of mechanical ventilation, and improving inflammatory status and ICU survival. Further prospective and large-scale, controlled studies are needed to confirm these results.  相似文献   
79.
AIM: To confirm the efficacy and safety of bevacizumab/XELOX combination for the treatment of locally advanced or metastatic colorectal cancer(CRC)in Italy.METHODS: This multicentric, prospective, open-label study included patients with CRC previously untreated with chemotherapy. Patients were administered bevacizumab in combination with XELOX. The primary efficacy end-point was progression-free survival(PFS). Secondary end-points included time to overall response(TOR), duration of response(DOR), time to treatment failure(TTF) and overall survival(OS).The incidence and type of adverse events AEs and severe AEs were evaluated. Also, the mutational status of BRAF and KRAS was assessed by high resolution melting and direct sequencing, and quality of life(QoL)was measured by the EuroQoL EQ-5D questionnaire at baseline and at the last visit.RESULTS: The intention-to-treat population included197 patients(mean age: 62.3 ± 9.9 years, 56.4%males). At baseline, 16/34 evaluable subjects(47.1%)harbored a KRAS and/or a BRAF mutation; the mean QoL index was 80.2 ± 14.3. First-line therapy was given for 223.7 ± 175.9 d, and after a mean followup of 387.7 ± 238.8 d all patients discontinued from the study mainly for disease progression(PD, 45.4%)and AEs(25.4%). Median PFS was 9.7 mo(95%CI:8.4-10.5) and the median values for secondary endpoints were: TOR = 3.9 mo(95%CI: 2.6-4.7), DOR= 8.5 mo(95%CI: 7.3-10.3), TTF = 6.7 mo(95%CI:6.0-7.7) and OS = 23.2 mo(95%CI: 20.1-27.2).Patients carrying at least one lesion had a lower overall response rate(66.7% vs 88.9%) and a lower probability of achieving complete or partial response than those without mutations, but the difference in relative risk was not statistically significant(P =0.2). Mean EQ-5D-3L raw index score significantly decreased to 74.9 ± 19.1 at the last visit(signed-rank test, P = 0.0076), but in general the evaluation on QoL perceived by patients was good.CONCLUSION: The efficacy of bevacizumab in combination with XELOX in terms of PFS in patients with aCRC or mCRC in Italy was confirmed, with acceptable toxicity.  相似文献   
80.

Aim of the study

n-Hexanic and ethanolic extracts from twelve plants (Brugmansia suaveolens Brecht. et Presl., Eupatorium laevigatum Lam., Galinsoga parviflora Cav., Iresine herbstii Hook., Kalanchöe tubiflora Hamet-Ahti, Petiveria alliacea L., Pluchea sagittalis (Lam.) Cabrera, Piper regnellii DC., Schinus molle L., Sedum dendroideum Moç et Sessé ex DC., Waltheria douradinha St. Hill., Xanthium cavanillesii Schouw.) used in traditional South Brazilian medicine as wound healing agents were investigated in various biological assays, targeting different aspects in this complex process.

Materials and methods

The extracts were investigated on NF-κB DNA binding, p38α MAPK, TNF-α release, direct elastase inhibition and its release as well as on caspase-3. Fibroblasts migration to and proliferation into the wounded monolayers were evaluated in the scratch assay, the agar diffusion test for antibacterial and the MTT assay for cytotoxic effects.

Results

The hydrophilic extracts from Galinsoga parviflora, Petiveria alliacea, Schinus molle, Waltheria douradinha and Xanthium cavanillesii as well as the lipophilic extract of Waltheria douradinha turned out to be the most active ones.

Conclusions

These results increase our knowledge on the wound healing effects of the investigated medicinal plants. Further studies are necessary to find out the effective secondary metabolites responsible for the observed effects.  相似文献   
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