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A 1H and 13C NMR study on the inclusion complex of paroxetine with β-cyclodextrin was carried out in order to define the stoichiometry of the association and its strength. Proton and carbon chemical shift measurements of paroxetine and β-cyclodextrin were performed at several molar ratios and temperatures, allowing the determination of a 1:1 stoichiometry and an association constant value of the order of 2 × 103 for the paroxetine–β-cyclodextrin complex. Overhauser effects in the rotating frame were also measured, and the experimental interproton distance constraints have been used for molecular model building of the complex. The obtained model indicates that the benzodioxolyl moiety of paroxetine is deeply inserted in the cavity of the cylindrical structure of β-cyclodextrin, while the fluoro-phenyl ring lays above the wider rim.  相似文献   
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In Italy, serogroup C meningococci of the clonal complex cc11 (MenC/cc11) have caused several outbreaks of invasive meningococcal disease (IMD) during the past 20 years. Between December 2019 and January 2020, an outbreak of six cases of IMD infected with MenC/cc11 was identified in a limited area in the northern part of Italy. All cases presented a severe clinical picture, and two of them were fatal. This report is focused on the microbiological and molecular analysis of meningococcal isolates with the aim to reconstruct the chain of transmission. It further presents the vaccination strategy adopted to control the outbreak. The phylogenetic evaluation demonstrated the close genetic proximity between the strain involved in this outbreak and a strain responsible for a larger epidemic that had occurred in 2015 and 2016 in the Tuscany Region. The rapid identification and characterisation of IMD cases and an extensive vaccination campaign contributed to the successful control of this outbreak caused by a hyperinvasive meningococcal strain.  相似文献   
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Patients with essential thrombocythemia (ET) often suffer from neurological symptoms (NS) not ever resulting from previous thrombotic cerebral events (TCE). We reported NS occurred in 282 patients, in order to identify the factors influencing ET‐related NS in the absence of TCE, and the response to therapy. Overall, 116 of 282 patients (41%) presented NS; 101 of them (87%) reported subjective transient and fluctuating NS, without concurrent TCE, which we defined as ET‐related NS, by frequency: cephalalgia, chronic paresthesias, dizziness or hypotension, visual disturbances, and tinnitus. In univariate analysis, ET‐related NS resulted more frequently in young people (P = 0.017) and in females (P = 0.025). We found a higher prevalence of JAK2V617F mutation in ET‐related NS patients (P = 0.021). In multivariate analysis, gender (P = 0.024) and JAK2V617F mutation (P = 0.041) remained significantly associated with the development of ET‐related NS, with a risk of about four times higher for JAK2V617F‐mutated patients (OR = 3.75). Ninety‐seven of 101 patients with ET‐related NS received an antiplatelet (AP) agent at the time of NS, whereas only selected high‐risk ET‐related NS patients were treated with a cytoreductive drug, according to the published guidelines and similarly to patients without NS. We observed that only 32 of 97 (33%) patients with ET‐related NS achieved a complete response after AP treatment. Among the 65 non‐responder patients, 36 (55.4%) improved NS after the introduction of cytoreductive therapy; therefore, the addition of cytoreductive treatment should be considered in this setting.  相似文献   
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Journal of Artificial Organs - To investigate by a lumped parameter model the feasibility of increasing the pulsatility of a continuous flow VAD, implanting an active valvulated outflow...  相似文献   
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Mechanical ventilation is a current support therapy for newborns affected by respiratory diseases. However, several side effects have been observed after treatment, making it mandatory for physicians to determine more suitable approaches. High fidelity simulation is an efficient educational technique that recreates clinical experience. The aim of the present study is the design of an innovative and versatile neonatal respiratory simulator which could be useful in training courses for physicians and nurses as for mechanical ventilation. A single chamber prototype, reproducing a pulmonary lobe both in size and function, was designed and assembled. Volume and pressure within the chamber can be tuned by the operator through the device control system, in order to simulate both spontaneous and assisted breathing. An innovative software-based simulator for training neonatologists and nurses within the continuing medical education program on respiratory disease management was validated. Following the clinical needs, three friendly graphic user interfaces were implemented for simulating three different clinical scenarios (spontaneous breathing, controlled breathing and triggered/assisted ventilation modalities) thus providing physicians with an active experience. The proposed pulmonary simulator has the potential to be included in the range of computer-driven technologies used in medical training, adding novel functions and improving simulation results.  相似文献   
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BackgroundTo explore the prognostic value of left ventricular (LV) longitudinal systolic dysfunction in patients with hypertension.MethodsIn 156 hypertensive subjects, LV longitudinal systolic function was assessed by echocardiographic measurement of M-mode left atrioventricular plane displacement (AVPD) and Tissue Doppler (TD)-derived mitral annulus peak systolic velocity (S(m)). Patients were followed for development of the following cardiovascular events: congestive heart failure requiring hospitalization, new-onset angina, nonfatal myocardial infarction, coronary revascularization procedures, transient ischemic attack, nonfatal stroke, and cardiovascular death.ResultsOver a follow-up of 23.3 +/- 5.4 months, 24 patients had 29 events. Both longitudinal systolic indices were predictive of outcome (hazard ratios: AVPD, 0.24, P < 0.001; S(m), 0.22; P < 0.001). AVPD 相似文献   
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Pulmonary atresia with ventricular septal defect is a complex congenital heart disease. We report a case of a 46-year-old woman with pulmonary atresia and ventricular septal defect, surgically treated when she was 15 years old with an implant of a conduit between ascending aorta and left pulmonary branch. A 64-slice computed tomography was performed to assess the conduit patency. The contrast enhanced MDCT study showed the conduit was pervious and correctly connected with an enlarged left pulmonary artery implant of a conduit between ascending aorta and left pulmonary branch.  相似文献   
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