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101.
The purpose of the present paper was to clarify the link between the attention and arousal level that supports the basis of the cognitive dysfunction in schizophrenia, by investigating the relationship between the simple reaction time and the closed-eye eye movements in 30 patients with schizophrenia and 20 healthy controls. In terms of closed-eye eye movements during the simple reaction time test, healthy controls showed an increase of s-type (small and slow) eye movements after the end of the preparatory interval (PI) in both regular and irregular series, while the patients with schizophrenia, particularly those in whom the cross-over phenomenon was observed, showed no changes and maintained a hyperarousal level during the regular PI test. These results indicate that the patients with schizophrenia could not maintain appropriate attention during the burden tasks and their hyperarousal level persisted. It is therefore suggested that there is a close relationship between attentional deficit and hyperarousal among patients with schizophrenia.  相似文献   
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Background: Our purpose was to evaluate the effectiveness of a newly developed non‐invasive traction technique known as thin endoscope‐assisted endoscopic submucosal dissection (TEA‐ESD) procedure for the removal of colorectal laterally spreading tumors (LST). Patients and Methods: A total of 37 LST located in the rectum and distal sigmoid colons of 37 patients were eligible for outcome analysis. Twenty‐one LST were treated with TEA‐ESD and were then retrospectively compared to 16 LST that had previously been treated with standard ESD. Tumor size, en bloc resection rate, procedure time, combined number of different electrical surgical knives used during each procedure and associated complications were evaluated in this case–control study. Results: There was no statistically significant difference in tumor size between the TEA‐ESD group and the ESD control group (43.6 ± 16 mm and 42.4 ± 14 mm, respectively). All LST were successfully resected en bloc in both groups. Procedure duration was shorter for the TEA‐ESD group than the ESD control group, although the difference was not statistically significant (96 ± 53 minutes vs 116 ± 74 minutes; P = 0.18). The percentage of cases in which only one electrical surgical knife was used during the entire procedure was significantly higher in the TEA‐ESD group compared to the ESD control group (85.7% vs 31.3%; P = 0.0005). There were no perforations in the TEA‐ESD group while the ESD control group experienced one perforation. At the present time, TEA‐ESD is limited to the rectum and distal sigmoid colon. Conclusion: It was technically easier, safer and more cost‐effective to perform ESD for LST in the rectum and the distal sigmoid colon using the newly developed TEA‐ESD traction technique.  相似文献   
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Aortic insufficiency (AI) is a worrisome complication under left ventricular assist device (LVAD) support. AI progression causes LVAD-left ventricular (LV) recirculation and can require surgical intervention to the aortic valve. However, the limitations of LVAD support are not well known. Using an animal model of LVAD with AI, the effect of AI progression on hemodynamics and myocardial oxygen metabolism were investigated. Five goats (Saanen 48?±?2 kg) underwent centrifugal type LVAD, EVAHEART, implantation. The AI model was established by placing a vena cava filter in the aortic valve. Cardiac dysfunction was induced by continuous beta-blockade (esmolol) infusion. Hemodynamic values and myocardial oxygen extraction ratio (O2ER) were evaluated while changing the degree of AI which was expressed as the flow rate of LVAD-LV recirculation (recirculation rate). Diastolic aortic pressure was decreased with AI progression and correlated negatively with the recirculation rate (p?=?0.00055). Systolic left ventricular pressure (LVP) and mean left atrial pressure (LAP) were increased with AI progression and correlated positively with the recirculation rate (p?=?0.010, 0.023, respectively). LVP and LAP showed marked exponential increases when the recirculation rate surpassed 40%. O2ER was also increased with AI progression and had a significant positive correlation with the recirculation rate (p?=?0.000043). O2ER was increased linearly, with no exponential increase. AI progression made it difficult to reduce the cardiac pressure load, worsening myocardial oxygen metabolism. The exponential increase of left heart pressures could be the key to know the limitation of LVAD support against AI progression.  相似文献   
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Journal of Artificial Organs - A type-C mold based on in-body tissue architecture was previously developed for preparing small-diameter biotube vascular grafts with a 2-mm diameter and...  相似文献   
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The secretory prohormone chromogranin A (CHGA) is overexpressed in essential hypertension, a complex trait with genetic predisposition, while its catecholamine release-inhibitory fragment catestatin is diminished, and low catestatin predicts augmented adrenergic pressor responses. These findings from studies on humans suggest a mechanism whereby diminished catestatin might increase the risk for hypertension. We generated Chga and humanized mice through transgenic insertion of a human CHGA haplotype in order to probe CHGA and catestatin in vivo. Chga mice displayed extreme phenotypic changes, including: (a) decreased chromaffin granule size and number; (b) elevated BP; (c) loss of diurnal BP variation; (d) increased left ventricular mass and cavity dimensions; (e) decreased adrenal catecholamine, neuropeptide Y (Npy), and ATP contents; (f) increased catecholamine/ATP ratio in the chromaffin granule; and (g) increased plasma catecholamine and Npy levels. Rescue of elevated BP to normalcy was achieved by either exogenous catestatin replacement or humanization of Chga mice. Loss of the physiological "brake" catestatin in Chga mice coupled with dysregulation of transmitter storage and release may act in concert to alter autonomic control of the circulation in vivo, eventuating in hypertension.  相似文献   
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