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INTRODUCTION: Ischemic heart disease is a major cause of heart failure in western societies. However, the factors that may influence left ventricular function (LVF) recovery after an acute coronary syndrome (ACS) are still unclear. OBJECTIVE: To identify variables that may influence LVF evolution one year after ACS. METHODS: 104 patients hospitalized with ACS between 7/1/2001 and 12/31/2002 and with systolic dysfunction--defined as an echocardiographic ejection fraction (EF) < or = 45%--were randomly allocated to a planned coronary follow-up program (FUP) or a general cardiology clinic (GC); patients from both groups were also randomly referred to a structured cardiac rehabilitation program (CRP). EF was re-assessed at one year. We compared differences between patients who recovered left ventricular function (EF > 45%; group 1) and those who did not (group 2). RESULTS: One year after discharge, 44.2% of the patients had recovered function. There were no significant differences between the groups in gender (77.7 vs. 76.5% male), age (56 vs. 59 years), hypertension, diabetes, dyslipidemia, smoking habits or family history. A previous history of cardiovascular events was more frequent in group 2 (11.1% vs. 35.3%, p = 0.03). Cardiac catheterization was performed before discharge in 88.8% and 88.2% in groups 1 and 2 respectively (p = NS); no differences were found in coronary anatomy between the two groups. Angioplasty was performed in 54.2% in group 1 and 50% in group 2 (p = NS). There were no differences in the use of angiotensin-converting enzyme inhibitors (83.3% vs. 87.5%), beta-blockers (87.5% vs. 87.5%), nitrates (37.5% vs. 33.3%), aspirin (95.8% vs. 95.8%), statins (79.1% vs. 75%) or diuretics (20.8% vs. 45.8%). There was no significant difference in LVF recovery between patients randomized to FUP or GC (38.5% vs. 54.5%). 87.5% of patients who completed the CRP had normal EF at one year compared to 32.7% of patients not referred to the program (p = 0.009). Although EF improved in both groups, this improvement was greater in patients who completed a CRP (EF 8% vs. 5%, p = 0.003). CONCLUSION: A previous cardiovascular event and completion of a CRP were the only variables that influenced LVF recovery. Thus, enrollment in a CRP, in addition to standard therapy, could be an important therapeutic measure in patients with systolic dysfunction after ACS; our data suggest that these programs should be more widely used.  相似文献   
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Methicillin-resistant Staphylococcus aureus (MRSA) is a frequent cause of infection after orthotopic liver transplantation (OLT). Colonization with MRSA is associated with a higher risk of infection. Previous studies have shown a high prevalence of MRSA colonization among OLT candidates. However, the risk of colonization with MRSA after OLT is still unclear. The objective of this study was to estimate the incidence and the factors associated with colonization with MRSA after OLT. This was a prospective cohort study including patients submitted to OLT between the years 2000 and 2002. Surveillance cultures of nasal swab specimens were performed within the 1st 72 hours of hospital admission and, subsequently, on weeks 2, 6, 13, and 26. Patients whose baseline cultures revealed nasal carriage of MRSA were excluded. A total of 60 patients were included in the study. The median follow-up was 72 days. A total of 9 patients (15%) became colonized. In multiple logistic regression analyses, the use of a urinary catheter for > or =5 days (P = .006), postoperative bleeding at the surgical site (P = .009), and preoperative use of fluoroquinolones (P = .08) were associated with a higher risk of colonization. Patients without any of these risk factors did not become colonized. In conclusion, nasal carriage of MRSA is frequently acquired after OLT. Periodic postoperative screening for MRSA carriage should be an integral component in programs designed to reduce nosocomial MRSA transmission in these patients. Further studies are needed to set up and validate a predictive model that could allow targeting postoperative screening to high-risk OLT recipients.  相似文献   
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Several observations point to the involvement of disturbed lipid biology in schizophrenia. Reduced response to niacin flushing test, which involves vasodilatation induced by prostaglandin D2 (PGD2), is among the evidences, together with decreased CSF levels of lipocalin-type prostaglandin D2 synthase (PTGDS), the enzyme responsible for the synthesis of PGD2 in the brain. Since PTGDS is also a carrier for lipophilic molecules such as retinoids and thyroid hormones, altered PTGDS levels might influence both PGD2-mediated signaling, and vitamin A and thyroid hormone availability. To test whether genetic variants of PTGDS are involved in the etiology of schizophrenia, we searched for variants in the coding and regulatory regions of the gene. We identified four previously described polymorphisms. Using two case-control samples from Portugal and Brazil, none of the polymorphisms tested was associated with the disease. In addition, no transmission distortion was observed in an independent parents-offspring sample from the Azorean Islands. Our data do not support the involvement of the PTGDS gene in the etiology of schizophrenia.  相似文献   
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We describe a novel method for the detection of human rhinoviruses in clinical samples, using the polymerase chain reaction. Two synthetic oligonucleotide primers were produced that bind in the 5' noncoding region of all rhinovirus serotypes tested, about 350 nucleotides apart, and were used to prime polymerase chain reaction amplification of the intervening stretch of DNA. The product of this reaction, which can be clearly visualized by gel electrophoresis, is a discrete 380 bp band, the occurrence of which is diagnostic of the presence of a rhinovirus in the clinical sample analysed. The technique, which is rapid, sensitive, and reliable, has been used successfully for all the different rhinovirus serotypes tested to date in our laboratory. However, the sensitivity of detection is greatly dependent on the inclusion of both tRNA and vanadyl complexes during the viral RNA extraction process. Using this technique, under optimal conditions, we were able to detect virus in clinical samples with titres as low as TCID50 10(2.5).  相似文献   
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The authors present the results of a dermatological survey conducted among the Xavánte Indians from the Pimentel Barbosa Reservation, state of Mato Grosso, Brazil Scabies, pediculosis, and pioderma were the most frequent diseases, clearly related to poor hygiene. The finding of perleche indicates the presence of nutritional deficiency. Endemic pemphigus foliaceus (fogo selvagem) was the most serious dermatological affection found in this population.  相似文献   
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BACKGROUND: This prospective, randomized study was conducted to evaluate the quality of postoperative pain relief when using dexketoprofen, ketoprofen, or paracetamol after outpatient knee arthroscopy. METHODS: Without premedication, 45 ASA physical status I-II patients undergoing elective outpatient knee arthroscopy with combined sciatic-femoral nerve block, were randomly allocated to receive either 25 mg oral dexketoprofen (n = 15), 50 mg oral ketoprofen (n = 15), or 500 mg oral paracetamol (n = 15) before block placement. After completion of surgery the same pain medication was given according to standard protocols, while 50 mg oral tramadol were allowed as rescue analgesic if required by the patient. After standard discharge criteria had been fulfilled, patients were discharged from the day-surgery unit, while a telephone follow-up was performed the day after surgery using standard questionnaires evaluating the quality of pain relief during the first 24 hours after surgery. Total consumption of rescue tramadol, maximum pain complained of after hospital discharge, as well as the visual analogue scale of pain measured at hospital discharge were assessed by an independent trained observer. RESULTS: No differences in anthropometric variables, duration of surgical procedure, and fulfillment of discharge criteria were observed between the three groups. The degree of pain measured at rest at hospital discharge was similar in the three groups, while the VAS measured during motion was higher in patients receiving paracetamol (24 +/- 2.5 mm) than in those patients treated with dexketoprofen (13 +/- 6 mm) or ketoprofen (17 +/- 5 mm) (p = 0.016). Two patients (one in ketoprofen group and one in paracetamol group) required rescue tramadol after hospital discharge; however, no differences in maximum pain complained of after surgery or patient acceptance were observed between groups. CONCLUSIONS: This prospective, randomized study demonstrated that in outpatients receiving arthroscopic knee surgery, the use of 75 mg/day dexketoprofen was as effective and safe as 150 mg/day racemate ketoprofen, with a better pain relief during motion compared to 2 g/day paracetamol when patients were discharged from the day-surgery unit.  相似文献   
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In this work, a comprehensive study of the influence on shear viscosity of polyelectrolyte concentration, persistence length, salt concentration and solvent quality is reported, using numerical simulations of confined solutions under stationary Poiseuille flow. Various scaling regimes for the viscosity are reproduced, both under good solvent and theta solvent conditions. The key role played by the electrostatic interactions in the viscosity is borne out when the ionic strength is varied. It is argued that these results are helpful for the understanding of viscosity scaling in entangled polyelectrolyte solutions for both rigid and flexible polyelectrolytes in different solvents, which is needed to perform intelligent design of new polyelectrolytes capable of fine tuning the viscosity in complex fluids.

The viscosity of polyelectrolytes in solution is predicted as a function of their concentration, persistence length, salt concentration and solvent quality, using mesoscale simulations. The persistence length is key to increasing viscosity.  相似文献   
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In February 2020 parliament passed the Cannabis Regulation Bill (2020) which regulates the cultivation and production of industrial hemp and medical cannabis. The country will only fully benefit from this development if the medical and scientific community can take the lead in enabling the country to exploit the plant''s potential to help address some of our economic and public health challenges. This special communication provides some basic information on cannabis and discusses its history and medical uses. Cannabidiol (CBD) has emerged as one of the most important cannabis-derived phytochemicals and has formed the basis for the growth of the medical cannabis industry. The scientific data on the mechanisms of the effects of CBD on the human neuroendocrine-immune network is reviewed and the first effective cannabis-based FDA-approved treatment for epilepsy discussed. Some clinical research that is being done on the antipsychotic and neuroprotective properties of CBD is also reviewed. A case is made for the potential of CBD as a neuroprotective adjunctive therapy for the prevention of neuropsychological sequelae associated with complicated malaria. The safety profile of CBD is reviewed and finally, the potential importance of the re-medicalization of cannabis-based therapies for the broader field of phytomedicine is pointed out.  相似文献   
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