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The nucleus of the optic tract (NOT) and the dorsal terminal nucleus of the accessory optic tract (DTN) are essential nuclei for the generation of slow-phase eye movements during horizontal optokinetic nystagmus. We recorded from 101 neurons (all directionally selective) in four NOT/DTN of three trained and behaving rhesus monkeys. Neuronal activity increased when stimuli moved ipsiversively with respect to the recording site and decreased below spontaneous activity when stimuli moved contraversively. While the monkey fixated a small spot, some NOT/DTN neurons did not respond at all to the retinal image slip of a whole-field random dot pattern; others showed a monotonic increase of activity to increasing velocities of that stimulus. The velocity range tested was up to 100°/s. During the execution of optokinetic nystagmus, 39 of 73 cells tested showed a velocity-tuned response with an average optimum at 21°/s retinal image slip. Following saccades during optokinetic nystagmus (quick phases), the NOT/DTN neuronal activity briefly attained the level of spontaneous activity, as predicted from the velocity selectivity during optokinetic nystagmus. Immediately upon cessation of optokinetic stimulation in the preferred direction, NOT/DTN activity returned to the spontaneous level and did not reflect the ongoing optokinetic afternystagmus in darkness. Most NOT/DTN neurons displayed direction selectivity also during smooth pursuit. Twenty-one of 50 cells tested (42%) always responded to the retinal slip of the target (target velocity cells), 16 cells (32%) responded to the retinal slip of the background (background velocity cells), and 13 cells (26%) did not respond at all during smooth pursuit. We conclude from our results that the NOT/DTN is an essential structure for the processing of the direction and speed of retinal image slip. This information is then used for the generation and maintenance of slow eye movements, preferentially during horizontal optokinetic nystagmus but also during pursuit eye movements.  相似文献   
3.
Unbalanced translocations generating trisomy of 1q are common in Wilms tumor (WT). We present eight unbalanced 1q translocations from seven tumors and a review of the literature. An unbalanced translocation that results in a der(16)t(1q;16q) chromosome represents more than half of the published +1q generating translocations in WT. This translocation is also common to many other tumor types. Four of the tumors presented here contained this chromosome and,in two cases, it was the primary acquired cytogenetic abnormality within the tumor. The other four translocations involved 9q31, 9q34, 17p1?, and 21p11 as the partner to 1q. The chromosome 17 and 21 translocations occurred within the same tumor as apparently independent events. In contrast with the 16q translocations, these other translocations were secondary cytogenetic events, thereby indicating a role in tumor progression rather than initiation. Probes mapping to 1q12 and 1q21 were employed for fluorescence in situ hybridization and it was demonstrated that different 1q breakpoints are possible. In this series, the majority of breakpoints either mapped to 1q12 or were centromeric to this region.  相似文献   
4.
BackgroundWeb-based platforms used to enhance patient-provider communication are being explored to improve patient satisfaction and care delivery, and decrease cost. This study tested a web-based interactive patient-provider software platform (IPSP), JointCOACH, which enabled patient communication with their care team and preparatory/recovery guidance. The aims of this study are to compare (1) patient satisfaction and (2) healthcare resource utilization by patients who underwent total knee and hip replacements and added IPSP to standard of care (SOC).MethodsThis study is a prospective, randomized clinical trial at a single large academic healthcare system. Between May 2018 and March 2020, 399 patients undergoing elective total hip or knee arthroplasty were randomized to SOC arm (n = 204) or SOC + IPSP arm (n = 195). Patient demographics, surgical details, and comorbidities were collected. Patient satisfaction was assessed using Visual Analog Scale and the Picker Patient Experience-15. Healthcare utilization was measured using length of stay, emergency department and office visits, office calls, readmissions, and reoperations at 30 and 90 days after surgery.ResultsNo difference was found in length of stay between SOC and SOC + IPSP. No differences were found in 30-day or 90-day satisfaction or in healthcare resource utilization (P > .05) including number of office and emergency department visits, phone calls, and readmissions.ConclusionStatistical differences were not found in satisfaction and healthcare utilization with the addition of IPSP to SOC. IPSP can be used to reinforce patient education and communication between the patient and provider, and should be evaluated as an element of virtual care rather than supplementing traditional in-office follow-up.Clinicaltrials.govMore information on this study can be found at clinicaltrials.gov NCT03499028.  相似文献   
5.
Peer victimization is a common stressor experienced by children. Although peer victimization has been studied extensively, few studies have examined the potential link between peer victimization and posttraumatic stress disorder (PTSD), and no studies of which we are aware have examined this link among children in primary school. The paucity of studies examining the link between PTSD and peer victimization in primary school is surprising because peer victimization occurs more frequently and is more likely to be physical among 7‐ and 8‐year‐old children. This study assessed the relationship between peer victimization and PTSD in a sample of 358 elementary school children (ages 6–11 years). Results indicated that peer victimization accounted for 14.1% of PTSD symptom severity among boys and 10.1% among girls. Additionally, we found gender differences in the types of peer victimization that were most associated with PTSD symptom severity (d = 0.38). The long‐term developmental consequences that may be associated with peer victimization‐linked PTSD symptomatology are discussed.  相似文献   
6.
Inducible Treg (iTreg) cells generated from Ag‐stimulated naïve CD4+ T cells in the periphery play an important role in regulating immune responses. TGF‐β is a key cytokine that promotes this conversion process; however, how this process is regulated in vivo remains unclear. Here, we report that γδ T cells play a crucial role in controlling iTreg generation and suppressor function. Ag‐induced iTreg generation was significantly enhanced in C57BL/6 mice in the absence of γδ T cells. Inhibition of iTreg conversion was mediated by IFN‐γ produced by activated γδ T cells but not by activated CD4+ T cells. BM chimera experiments further confirmed γδ‐derived IFN‐γ‐dependent mechanism in regulating iTreg generation in vivo. Lastly, human peripheral blood γδ T cells also interfere with iTreg conversion via IFN‐γ. Our results suggest a novel function of γδ T cells in limiting the generation of iTreg cells, potentially balancing immunity and tolerance.  相似文献   
7.
The aim of this retrospective study is to determine the frequency, type, microbiological characteristics and outcome of HAIs in the elderly (age ≥ 65) and to compare the data with younger patients in a Turkish Training and Research Hospital. From January 2008 to December 2009, the infection control team analyzed HAIs among 60,585 hospitalized patients (20,109 aged ≥ 65 and 40,747 aged between 18 and 64 years) with a total number of 419,017 patient days. A total of 825 HAIs episodes were detected in 607 patients, of which 395 episodes were in 301 elderly patients. The incidence of HAIs per 1000 patient days was 2.49 in the elderly and 1.64 in the younger patients’ group (p < 0.001). The most common site of infection in the elderly patients was the urinary tract, whereas in non-elderly group this was the lower respiratory tract. The incidence density of urinary tract infections, respiratory tract infections, surgical site, skin and soft tissue infections, primary bacteremia, and prosthesis infections were significantly higher in the elderly group (p < 0.05). Gram-negative species were the most frequently isolated agents in both groups. There were no significant differences between the groups in the frequency of isolated pathogens or antibiotic susceptibility patterns. Overall, the fatality rate was found 16.8%. The elderly patients were more likely to have crude mortality rates (22% vs. 12%; p < 0.01). The death was most often related to pneumonia, primary bacteremia or intravascular catheter infections in both groups.  相似文献   
8.
Awareness of the problem of false electrocardiographic diagnosis of septal infarction due to cranially misplaced precordial leads V1 and V2, a common technical error, is important because this pseudo-pathologic finding can trigger unnecessary medical procedures and have other adverse sequelae. The non-trivial nature of this problem is emphasized by the case of a patient in whom the misdiagnosis caused loss of an employment opportunity. We demonstrate how P wave morphology in lead V2 can aid the clinician in suspecting erroneous right precordial lead placement in cases of apparent septal infarction. Ultimately, improved education of health care personnel regarding accurate precordial lead positioning technique is needed to minimize the occurrence of this electrocardiographic misdiagnosis.  相似文献   
9.
Certain homeostatic functions are particularly important to the success of extensive surgery. For example metabolic homeostasis, inflammation and tissue repair, coagulation and immune defense against infection are all of great importance. In patients undergoing allogeneic hematopoietic stem cell transplantation (ASCT), the ability to mount adequate inflammatory responses is severely impaired. Thrombocytopenia is common making coagulation inadequate for any kind of invasive procedure, let alone extensive surgery. For this reason, abdominal surgery in neutropenic patients is associated with very high mortality rates of between 50 and 70 % [1]. Here, we describe a patient with high-risk myelofibrosis who required extensive abdominal surgery during the aplastic phase only 7 days after ASCT due to severe abdominal hemorrhage. This patient’s successful recovery shows that extensive surgery is possible even during the aplastic phase after ASCT. Interestingly, we also found that radical splenectomy 7 days after stem cell transplantation did not lead to any significant loss of infused stem cells.  相似文献   
10.
This study evaluated two different stretching protocols employed during a period of hind-limb immobilization in terms of their effects on muscle morphology. Quantitative data regarding the soleus muscle were obtained based on the clinical hypothesis that a high frequency of this exercise would improve the recovery of muscle structure. Twenty-four male Wistar rats were divided into four groups (n = 6 each): the control group (C); the immobilized group, in which the left hind limb was immobilized in order to maintain the soleus muscle in a fully shortened position for 3 weeks (I); the 'immobilized and stretched every 3 days' group, in which the left hind limb was immobilized as in the immobilized group, but with the soleus muscle stretched every 3 days for 40 min (Ist3); and the 'immobilized (as in the immobilized group) and stretched every 7 days' group (ISt7). All soleus muscles were excised 21 days after the beginning of the experiment, and were processed for (1) haematoxylin and eosin and myosin ATPase to evaluate muscle morphology and cross-sectional area and the proportions of the different fibre types, and (2) ultrastructural analysis. The cross-sectional area was found to have decreased in all fibre types (I, II and C), mainly in ISt7, when compared with the C group and ISt3 group. The proportion of the different fibre types did not show statistical difference between groups. Light and electron microscopy examination revealed signs of cell degeneration that was more intense in the group immobilized and stretched three times a week. In conclusion, sessions of passive stretching applied to the soleus during immobilization induce muscle fibre injury, suggesting that this therapeutic tool should be applied carefully to disused muscles.  相似文献   
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