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Rodents have been the principal model to study brain anatomy and function due to their well-mapped brain architecture, rapid reproduction and amenability to genetic modification. However, there are clear limitations, for example their simpler neocortex, necessitating the need to adopt a model that is closer to humans in order to understand human cognition and brain conditions. Nonhuman primates (NHPs) are ideally suited as they are our closest relatives in the animal kingdom but in vivo imaging technologies to study brain structure and function in these species can be challenging. With the surge in NHP research in recent years, scientists have begun adapting imaging technologies, such as two-photon microscopy, for these species. Here we review the various NHP models that exist as well as their use in advanced microscopic and mesoscopic studies. We discuss the challenges in the field and investigate the opportunities that lie ahead.  相似文献   
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We conducted a retrospective study of 135 patients of stage IE/IIE extranodal natural killer/T cell lymphoma, nasal type (ENKTL) treated with CHOP as induction chemotherapy to find some valuable prognostic factors and analyze the usefulness of International Prognostic Index (IPI) and Korean Prognostic Index (KPI) in predicting prognosis. Most of the patients were in the low-risk group (IPI score 0?C1). Complete remission (CR) after induction chemotherapy was achieved in 31.8?% of the patients, which increased to 69.6?% after radiotherapy. The 2-, 5-, and 10-year overall survival (OS) rates were 60, 48, and 43?%, respectively. Patients with better performance status (ECOG 0-1), normal serum LDH level, without local invasiveness, low KPI scores, and IPI score of 0 had significantly better overall survival (P?<?0.05) in univariate analysis. Using multivariate analysis, we identified serum LDH level, ECOG PS score and local invasiveness to be independent prognostic factors. In conclusion, ENKTL is an aggressive lymphoma that shows heterogeneity. The IPI and KPI score systems should be improved further to classify patients into different groups, and should be validated in larger prospective trials. Due to the multi-drug resistance mechanism of ENKTL, CHOP is no longer the state of art and novel drugs should be incorporated into future treatments.  相似文献   
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ObjectiveTo compare the value of the subcutaneous tunneling technique versus the normal technique in improving the outcomes of patients undergoing chemotherapy with peripherally inserted central catheters (PICCs).MethodsOne hundred thirty patients were randomly divided into an experimental group (subcutaneous tunneling technique) and control group (normal technique) according to the PICC placement technique, and clinical data were compared between the groups.ResultsIn total, 129 PICCs were successfully inserted. Compared with the control group, the experimental group had a lower occurrence of complications after placement (especially catheter dislodgement: 3.1% vs. 15.4%, venous thrombosis: 3.1% vs. 15.4%, and wound oozing: 14.1% vs. 27.7%), lower occurrence of unscheduled PICC removal (3.1% vs. 13.8%), greater comfort during placement (14.16 ± 2.21 vs. 15.09 ± 2.49 on a scale ranging from 6 to 30 points, with higher scores indicating lower degrees of comfort), and lower costs of PICC maintenance (median (interquartile range) per-day maintenance cost: 13.90 (10.99–32.83) vs. 15.69 (10.51–57.46) Yuan). The occurrence of complications and amount of bleeding during placement were not significantly different between the two groups.ConclusionsThe subcutaneous tunneling technique can improve PICC placement by reducing complications and costs of maintenance with better patient comfort during placement.  相似文献   
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After treatment of fractures in the neck of the mandible by means of immobilization of the dentition, often more or less severe manifestations of malocclusion remain. It was hypothesized that this is caused by an altered articulation in the jaw joint on the affected side. Furthermore, it was hypothesized that an anteriorly displaced condyle, as observed frequently as a side effect of the treatment, is caused by pull of the lateral pterygoid muscle, despite maxillomandibular fixation.Intervention experiments were performed in silico to test these hypotheses. With a biomechanical model of the human masticatory system alterations were applied mimicking a fractured mandibular neck and configurations that had been observed after healing.It was predicted that the altered articulation in the jaw joint caused asymmetrical jaw movements despite symmetrical muscle activation. The jaw was predicted to close with an open bite similar to clinical observations. The predicted laterodeviations, however, were not in accordance with clinical observations. Despite maxillo-mandibular fixation the lateral pterygoid muscle was able to pull the mandibular condyle out of its fossa in anterior direction. Consequently, despite some methodological limitations, in general the predictions corroborated the hypotheses.  相似文献   
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