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31.
Estimation of metabolic changes during neuronal activation represents a challenge for in vivo MRS, especially for metabolites with low concentration and signal overlap, such as lactate. In this work, we aimed to evaluate the feasibility of detecting lactate during brain activation using a long (144 ms) semi‐LASER sequence at 7 T. spectra were acquired on healthy volunteers ( ) during a paradigm with 15 min of visual stimulation. Outer‐volume signals were further attenuated by the use of saturation slabs, and macromolecular signals in the vicinity of the inverted lactate peak were individually fitted with simulated Lorentzian peaks. All spectra were free of artefacts and highly reproducible across subjects. Lactate was accurately quantified with an average Cramér‐Rao lower bound of 8%. Statistically significant ( , one‐tailed ‐test) increases in lactate ( 10%) and glutamate ( 3%) levels during stimulation were detected in the visual cortex. Lactate and glutamate changes were consistent with previous measurements. We demonstrated that quantification of a clear and non‐contaminated lactate peak obtained with a long TE sequence has the potential of improving the accuracy of functional MRS studies targeting non‐oxidative reaction pathways.  相似文献   
32.
ABSTRACT

Sexual minority women (SMW) face both increased risk for unintended pregnancy and barriers to achieving wanted pregnancy, but little research investigates SMW’s pregnancy desires. To fill this gap, we conducted five focus groups and 11 in-depth interviews with 20-30-year-old SMW in three US cities. Findings highlight that the heteronormative pregnancy planning paradigm lacks salience for SMW. While some SMW clearly wish to avoid pregnancy, many others are unsure, and factors influencing this uncertainty include relationship context, anticipating logistical barriers, and discord between queer identity and pregnancy.  相似文献   
33.
Consensus has yet to be reached about the prevention and treatment of medication-related osteonecrosis of the jaw (MRONJ), which is a treatment sequela of several antiresorptive therapies and other pharmaceutical interventions. Several epidemiologic studies have identified periodontal disease (PD) as a risk factor for this outcome. Thus, the objective of this systematic review and meta-analysis was to investigate this association and its magnitude. A systematic search in MEDLINE via PubMed, Scopus and ISI Web of Science, and a meta-analysis were undertaken. Observational studies that gathered information regarding prefixed definitions for both outcomes were selected, and the relevant information was then extracted, and their risk of bias was evaluated using the Newcastle-Ottawa Scale. The protocol of the study was registered on PROSPERO (CRD42019125646). The initial search yielded 757 eligible records, of which 12 were deemed adequate for inclusion (5 cohort studies and 7 case-control studies). On a random-effects meta-analysis, the risk of PD in MRONJ-affected sites compared with at-risk non-affected patients was significantly greater, with a risk ratio of 2.75 (95% CI: 1.67-4.52). Nonetheless, from a pooled analysis of three standardized periodontal measures (ie plaque index, clinical attachment loss and probing depth) no significant results were obtained. MRONJ appears to be associated with an increase in prevalence of PD. The direction of this association, and the factors influencing it must be investigated using further prospective data, and likewise, the possibility for using periodontal therapy as a prevention strategy must be looked into. Periodontal screening needs to be made an indispensable requisite for clinicians in order to establish a correct multidisciplinary approach in MRONJ.  相似文献   
34.
Introduction: Following life-threatening junctional trauma, the goal is to limit blood loss while expediting transfer to operative rescue. Unfortunately, life-threatening abdominal-pelvic or junctional hemorrhage is often not amenable to direct compression and few temporizing strategies are available beyond hemostatic dressings, hypotensive resuscitation, and balanced transfusion. Objectives: In this study, we evaluated proximal external aortic compression to arrest blood flow in healthy adult men. Methods: This was a simulation trial of proximal external aortic compression, for life-threatening abdominal-pelvic and junctional hemorrhage, in a convenience sample of healthy adult male volunteers. The primary end points were cessation of femoral blood flow as assessed by pulse wave Doppler ultrasound at the right femoral artery, caudal to the inguinal ligament. Secondary end points were discomfort and negative sequelae. Results: Aortic blood flow was arrested in 12 volunteers. Median time to blood flow cessation was 12.5?seconds. Median reported discomfort was 5 out of 10. No complications or negative sequelae were reported. Conclusion: This trial suggests that it may be reasonable to attempt temporization of major abdominal-pelvic and junctional hemorrhage using bimanual proximal external aortic compression. In the absence of immediate alternatives for this dangerous and vexing injury pattern, there appear to be few downsides to prehospital proximal external aortic compression while concomitantly expediting definite care.  相似文献   
35.

Background

Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain.

Methods

We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male).

Results

Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians.

Conclusions

Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation.  相似文献   
36.
Wistar Audiogenic Rat (WAR) strain is an animal model for epilepsy studies, the chronic multifactorial disease that affects millions of people worldwide. The animals of this strain are genetically predisposed to sound-induced seizures, called audiogenic seizures, and have been used for many years in studies to understand the mechanisms involved in the epilepsies and their neuropsychiatric comorbidities, as well as the screening of potential anti-convulsant agents. Nevertheless, little is known about the reproductive characteristics of these animals. The main goal of this study was to characterize the female reproductive performance and the fetal growth of WARs in comparison to the Wistar rats, obtaining important information for physiology and behavioral studies, as well as for the preservation of the strain. The results indicated few differences between WAR and Wistar regarding the female reproductive performance. There was no significant difference in the number of pregnant females by mating, number of live births per female, number of cells per blastocyst, and several characteristics related to reproductive performance, such as pre- and post-implantation losses. However, significant differences were observed in birth weight and weight gain until weaning, with WAR animals presenting a body weight below Wistar at birth and reduced body weight gain during the lactation period. In addition, the WAR females showed lower body weight on the day 20 of pregnancy and a larger number of corpora lutea, when compared with those of Wistar animals. Thus, we conclude that although Wistar and WAR strains have few differences in their reproductive performance, which might impact future physiological life challenges or others experimentally induced procedures, it still is a very viable strain regarding reproduction.

Abbreviations: CONCEA: National Council for the Control of Animal Experimentation; GEPR: genetically epilepsy-prone rats; WAR: Wistar Audiogenic Rat.  相似文献   

37.
BackgroundThe efficacy of ticagrelor in the long-term post–ST-segment elevation myocardial infarction (STEMI) treated with fibrinolytic therapy remains uncertain.ObjectivesThe purpose of this study was to evaluate the efficacy of ticagrelor when compared with clopidogrel in STEMI patients treated with fibrinolytic therapy.MethodsThis international, multicenter, randomized, open-label with blinded endpoint adjudication trial enrolled 3,799 patients (age <75 years) with STEMI receiving fibrinolytic therapy. Patients were randomized to ticagrelor (180-mg loading dose, 90 mg twice daily thereafter) or clopidogrel (300- to 600-mg loading dose, 75 mg daily thereafter). The key outcomes were cardiovascular mortality, myocardial infarction, or stroke, and the same composite outcome with the addition of severe recurrent ischemia, transient ischemic attack, or other arterial thrombotic events at 12 months.ResultsThe combined outcome of cardiovascular mortality, myocardial infarction, or stroke occurred in 129 of 1,913 patients (6.7%) receiving ticagrelor and in 137 of 1,886 patients (7.3%) receiving clopidogrel (hazard ratio: 0.93; 95% confidence interval: 0.73 to 1.18; p = 0.53). The composite of cardiovascular mortality, myocardial infarction, stroke, severe recurrent ischemia, transient ischemic attack, or other arterial thrombotic events occurred in 153 of 1,913 patients (8.0%) treated with ticagrelor and in 171 of 1,886 patients (9.1%) receiving clopidogrel (hazard ratio: 0.88; 95% confidence interval: 0.71 to 1.09; p = 0.25). The rates of major, fatal, and intracranial bleeding were similar between the ticagrelor and clopidogrel groups.ConclusionAmong patients age <75 years with STEMI, administration of ticagrelor after fibrinolytic therapy did not significantly reduce the frequency of cardiovascular events when compared with clopidogrel. (Ticagrelor in Patients With ST Elevation Myocardial Infarction Treated With Pharmacological Thrombolysis [TREAT]; NCT02298088)  相似文献   
38.
ABSTRACT

Various machine learning techniques have been developed for keratoconus detection and refractive surgery screening. These techniques utilize inputs from a range of corneal imaging devices and are built with automated decision trees, support vector machines, and various types of neural networks. In general, these techniques demonstrate very good differentiation of normal and keratoconic eyes, as well as good differentiation of normal and form fruste keratoconus. However, it is difficult to directly compare these studies, as keratoconus represents a wide spectrum of disease. More importantly, no public dataset exists for research purposes. Despite these challenges, machine learning in keratoconus detection and refractive surgery screening is a burgeoning field of study, with significant potential for continued advancement as imaging devices and techniques become more sophisticated.  相似文献   
39.
Objectives: Understanding inhaler preferences may contribute to improving adherence in COPD patients and improving long-term outcomes. This study aims to identify and quantify preferences for convenience-related inhaler attributes in French moderate-to-severe COPD patients, with discrete choice experiment (DCE) methodology.

Methods: Attributes were defined from a literature search, clinician and patient interviews: shape, dose insertion, dose preparation, dose release, dose confirmation, dose counter and reusability. An online DCE was conducted in respondents with self-reported COPD stage 2–4 recruited through a panel. The study questionnaire included twelve choice scenarios per respondent and questions on patient characteristics, treatment and disease severity. Statistical analyses used a mixed logit regression model with random effects. Utility scores were estimated for four types of inhalers: Inhaler A – soft mist inhaler; Inhaler B – reusable soft mist inhaler; Inhaler C – multi-dose dry powder inhaler; and Inhaler D – single dose dry powder inhaler.

Results: The study was completed by 153 patients (50 females); respondents were 50.4?years old on average; 13 different inhaler devices were reported. The most preferred inhaler is L-shaped, has dose preparation with capsule insertion and a dose counter, and is reusable. Inhaler profiles A and B had the highest utilities (mean of 1.2533 and 0.9578 respectively) compared to inhaler C (0.6315) and D (0.2200).

Conclusions: This study showed statistically significant results that the strongest drivers of preference in French users of inhalation devices for COPD are shape, dose counter and reusability. Convenience-related characteristics are important to patients and should be taken into account by clinicians prescribing these devices.  相似文献   

40.
Aim: The aim of study was to investigate the opportunities of local phlebectomy in the elimination of isolated pelvic-perineal reflux (PPR), as well as to determine the feasibility of endovascular embolization of the tributaries of internal iliac veins in PPR. Clinical trial no. NCT01598051.

Materials and methods: The work is based on the results of examination and treatment of 43 female patients with varicose veins of the pelvis, perineum, and lower extremities. Patients had no signs of pelvic congestion syndrome (PCS). All patients underwent duplex ultrasound scanning (DUS) and ovariography with pelvic phlebography (OPP). For the elimination of PPR, local phlebectomy was performed in the major labia and perineal area, with maximal possible mobilization of the vessel within the operative wound (33 patients). In 10 patients with isolated varicose transformation of the superficial veins on the posterior thigh, mini-phlebectomy was performed using the Varady phlebectomy extractors.

Results and discussion: The varicose syndrome of the external genitalia, perineum, and posterior thigh was successfully treated in 100% of patients. Findings suggest that thorough mobilization and excision of the veins of the pudendal labia, perineum, and subcutaneous veins of the thigh is a reliable method for eliminating the pathological reflux from the intrapelvic veins to the superficial veins of the perineum and lower extremities. No recurrences of vulvar, perineal varices or dilation of the veins of the lower extremities were observed in 100% of patients over the 3-year follow-up period.

Conclusion: Local phlebectomy is an effective technique for eliminating the isolated PPR in patients with varicose transformation of intrapelvic, vulvar, or perineal veins. Endovascular embolization of the tributaries of the internal iliac veins is not an essential component in the treatment of PPR. The present study has a limitation due to the absence of patients with PCS. The effectiveness of phlebectomy in the treatment of isolated PPR was studied.  相似文献   

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