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991.
The ability to predict the timing of forthcoming events, known as temporal expectation, has a strong impact on human information processing. Although there is growing consensus that temporal expectations enhance the speed and accuracy of perceptual decisions, it remains unclear whether they affect the decision process itself, or non-decisional (sensory/motor) processes. Here, healthy human participants (N = 21; 18 female) used predictive auditory cues to anticipate the timing of low-contrast visual stimuli they were required to detect. Modeling of the behavioral data using a prominent sequential sampling model indicated that temporal expectations speeded up non-decisional processes but had no effect on decision formation. Electrophysiological recordings confirmed and extended this result: temporal expectations hastened the onset of a neural signature of decision formation but had no effect on its build-up rate. Anticipatory α band power was modulated by temporal expectation and co-varied with intrinsic trial-by-trial variability in behavioral and neural signatures of the onset latency of the decision process. These findings highlight how temporal predictions optimize our interaction with unfolding sensory events.SIGNIFICANCE STATEMENT Temporal expectation enhances performance, but the locus of this effect remains debated. Here, we contrasted the two dominant accounts: enhancement through (1) expedited decision onset, or (2) an increase in the quality of sensory evidence. We manipulated expectations about the onset of a dim visual target using a temporal cueing paradigm, and probed the locus of the expectation effect with two complementary approaches: drift diffusion modeling (DDM) of behavior, and estimation of the onset and progression of the decision process from a supramodal accumulation-to-bound signal in simultaneously measured EEG signals. Behavioral modeling and neural data provided strong, converging evidence for an account in which temporal expectations enhance perception by speeding up decision onset, without affecting evidence quality.  相似文献   
992.
Cardiac amyloidosis (CA) is considered a rare disease with poor prognosis and limited therapeutic options. However, non-biopsy diagnostic modalities as well as emerging therapies are challenging this long-held belief. Radionuclide bone scintigraphy is increasingly being used in the diagnosis of transthyretin amyloid cardiomyopathy (ATTR-CA). As such, it is expected that the number of patients diagnosed with ATTR-CA will continue to rise. Emerging therapies decrease the progressive morbidity and mortality associated with ATTR-CA. The importance of early recognition of ATTR-CA is imperative as prompt initiation of these novel agents is essential to maximize their therapeutic potential. Herein, we outline the current approach to diagnosis of ATTR-CA and review the therapeutic management of the disease.  相似文献   
993.
IntroductionNeuromyelitis optica (NMO) and NMO spectrum disorders (NMO-SD) are inflammatory demyelinating diseases of the central nervous system. There are few epidemiological studies devoted to NMO, especially in Africa and the Middle East, but individual cases and series have been reported from many countries across the African continent.ObjectivesTo describe the epidemiology, diagnosis, and management of NMO patients followed at the Mohammed VI University Hospital of Marrakech.Patients and methodsThis was a hospital-based retrospective study of 52 patients with NMO diagnosed and followed at the Neurology department of the University Hospital of Marrakech from 2004 to July 2019. The 2006 diagnostic criteria of NMOSD were used for patients admitted before 2015 for inflammatory disease of the central nervous system and the 2015 diagnostic criteria of NMO-SD for all patients thereafter. Collected data were analysed using SPSS software.ResultsThe study concerned 52 patients, 18 males and 34 females. Median age at disease onset was 32.5 years (range 7–55). Mean time between symptom onset and diagnosis of NMO was nine months 18 days (range 7 days to 4 years). In most patients, manifestations included visual acuity, tetraparesis, and sensorial disorders. Refractory vomiting and hiccup were noted in the first attack in 19% of patients. Two patients had hypersomnia and polyphagia, and one had been treated for depression ten months before the development of severe tetraplegia. Magnetic resonance imaging did not show any brain lesions in 29% of patients. Cervical myelitis extending to more than three vertebrae was found in 60% of patients. AQP4-antibody assay was performed only in 57.7% of patients, and was positive in 38.4%; anti-MOG was positive in four anti-AQP4 seronegative patients. Management strategies for NMO-SD included methylprednisolone pulses (70% of patients), plasmapheresis (25%), and rituximab (since 2017) for 46%. Outcome was favourable in 40% of patients and has remained stable in 50% of them.ConclusionAnti-NMO assays, made available during the last five years with the help of The Guthy-Jackson Charitable Foundation, have led to a clear jump in the number of cases diagnosed. Major advances in the field of epidemiology, imaging, and pathophysiology of NMO-SD have led to improved patient care and outcome.  相似文献   
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BackgroundPneumatosis intestinalis (PI) is a rare condition usually occurring among adults who have undergone solid organ transplant and are taking steroid therapy. The coronavirus disease 2019 (COVID-19) virus uses angiotensin-converting enzyme 2 in gastrointestinal epithelium as a receptor for entry process. Due to the steroid intake, the COVID-19 virus is present in the patient's gastrointestinal tract for extended period of time. It may therefore increase the possibility of PI in such patients. It is usually asymptomatic, with a clinical spectrum ranging from indolent to life-threatening. Unfortunately, there are no algorithms concerning diagnosis and treatment of PI.Aim of studyThe aim of this study is to highlight the problem of PI induced by COVID-19, especially in high-risk groups such as solid organs recipients.ConclusionOn the basis of the presented case of a severe course of COVID-19–induced PI, we conclude that laparotomy with bowel resection can be a feasible and a safe option for treatment.  相似文献   
997.
ObjectivesRecent evidence has shown an association between postoperative ketorolac use and anastomotic leak in patients undergoing intestinal and colorectal operations, but this relationship has been minimally explored after esophagectomy. As the use of nonopioid pain control and enhanced recovery protocols is increasingly prioritized, determination of a possible correlation between perioperative ketorolac use and leak is essential.MethodsRecords of patients undergoing esophagectomy for adenocarcinoma at a single institution from 2006 to 2018 reviewed for occurrence of anastomotic leak. Institutional pharmacy records were queried for ketorolac administration during the surgical case through the time of discharge. Multivariable logistic regression was used to determine the relationship between ketorolac administration and anastomotic leak.ResultsA total of 1019 patients met inclusion criteria, the majority of whom were male (907, 89%) with a median age of 62 years. Patients predominantly presented with locoregionally advanced disease and were treated with initial chemoradiation. Ketorolac was administered to 686 patients (67%); use was observed to increase over the study period from 49% in 2006 to 92% in 2016. Conversely, anastomotic leak occurred in 87 patients (9%) overall and decreased over time from 15% (11/72) in 2006 to 2% (2/83) in 2018. Upon multivariable analysis, neither ketorolac administration evaluated as a categoric variable (odds ratio, 0.99; P = .958) or as a continuous variable using dose (odds ratio, 1.00; P = .843) demonstrated an association with anastomotic leak.ConclusionsKetorolac in the postoperative period after esophagectomy has become an integral component of enhanced recovery pathways and does not appear to be associated with anastomotic leak.  相似文献   
998.
999.
BackgroundMedical child abuse (MCA) is challenging to diagnose. Although young children are often affected, adolescents can be victims through caregiver coercion. Presentation is highly variable. Diagnosis is essential because of high associated morbidity and mortality.CaseWe describe the case of a 12-year-old girl who presented to multiple subspecialty clinics with reported menorrhagia. Despite reassuring clinical examinations, the family described menorrhagia that failed to respond to standard treatment. After an urgent evaluation for reported heavy bleeding revealed only scant blood, the diagnosis of MCA was made.Summary and ConclusionVaginal bleeding is a rare presentation of MCA, but must be considered whenever reported symptomatology does not follow physiologic patterns, respond to standard medical treatment, or correspond to clinical evaluation. Prompt identification is important to prevent further harm.  相似文献   
1000.
Recent experimental strategies to reduce graft-versus-host disease (GVHD) have focused largely on modifying innate immunity. Toll-like receptor (TLR)-driven myeloid differentiation primary response 88 (MyD88)-dependent signalling pathways that initiate adaptive immune function are also critical for the pathogenesis of GVHD. This study aimed to delineate the role of host MyD88 in the development of acute GVHD following fully major histocompatibility complex-mismatched allogeneic bone marrow transplantation (BMT). When myeloablated BALB/c MyD88 knock-out recipients were transplanted with C57BL/6 (B6) donor cells, they developed significantly more severe GVHD than wild-type (WT) BALB/c hosts. The increased morbidity and mortality in MyD88–/– mice correlated with increased serum levels of lipopolysaccharide and elevated inflammatory cytokines in GVHD target organs. Additionally, MyD88 deficiency in BMT recipients led to increased donor T cell expansion and more donor CD11c+ cell intestinal infiltration with apoptotic cells but reduced proliferation of intestinal epithelial cells compared with that in WT BMT recipients. Decreased expression of tight junction mRNA in epithelial cells of MyD88–/– mice suggested that MyD88 contributes to intestinal integrity. Cox-2 expression in the GVHD-targeted organs of WT mice is increased upon GVHD induction, but this enhanced expression was obviously inhibited by MyD88 deficiency. The present findings demonstrate an unexpected role for host MyD88 in preventing GVHD after allogeneic BMT.  相似文献   
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