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41.
Neurons in the temporal cortex changed their preferred direction of motion dependent on shape 总被引:1,自引:0,他引:1
To investigate neuronal mechanisms that integrate different visual modalities such as motion and shape, neuronal activities in the superior temporal polysensory area (STP) were recorded from monkeys that were watching rotating images. In total, 194 neurons were identified as visually responsive. Of these, 73 neurons (38%) showed differential response depending on both shape and direction of motion (MS neurons). Of these 73 neurons, 21 (29%) were identified as reversal type MS neurons (MSr neurons), that is, they responded to an opposite preferred direction when the shape was different. The results confirm that neurons in the STP can be simultaneously activated by different attributes of visual stimuli. The data also suggest that individual STP neurons can process more than one type of visual stimulus. 相似文献
42.
Osamu Mikami Shigenari Kawakita Kumiko Fujise Koh Shingu Hakuo Takahashi Tadashi Matsuda 《The Journal of urology》1996,155(4):1368-1371
Purpose
We evaluated plasma catecholamine levels during pneumoperitoneum in laparoscopic surgery.Materials and Methods
Plasma epinephrine and norepinephrine were evaluated in 29 patients who underwent laparoscopic retroperitoneal surgery in a half lateral decubitus position (group 1) or laparoscopic varicocelectomy in a Trendelenburg position (group 2).Results
The levels of epinephrine and norepinephrine increased significantly 5 minutes after carbon dioxide insufflation compared to levels after Veress needle insertion and just before insufflation. The elevation of catecholamine levels during laparoscopic procedures was greater in group 1.Conclusions
Our results indicate that carbon dioxide insufflation may cause catecholamine release during laparoscopic surgery. Careful monitoring of hemodynamics is mandatory at the beginning of the procedure. 相似文献43.
Watanabe T Mikami A Shigedo Y Motonishi M Honda H Kyotani K Uruha S Terashima K Teshima Y Sugita Y Takeda M 《Psychiatry and clinical neurosciences》2000,54(3):338-339
Severity of negative esophageal pressure (Pes) and apnea hypopnea index (AHI) were investigated in six cases of upper airway resistance syndrome (UARS) and 11 cases of obstructive sleep apnea syndrome (OSAS). The severity of negative Pes was represented by the highest peak (Pes Max) and the number of increased episodes (more than 13.5 cmH2O) per h (NPesI13.5). There was no significant correlation between Pes indices and AHI. Pes Max and NPesI13.5 were not different among severe OSAS (AHI > 30), mild OSAS (AHI < 30) and UARS. Apnea hypopnea index failed to represent the severity of negative Pes, which is an important aspect of the pathophysiology of sleep-disordered breathing. 相似文献
44.
Kurata C Uehara A Sugi T Ishikawa A Fujita K Yonemura K Hishida A Ishikawa K Tawarahara K Shouda S Mikami T 《Nephron》2000,84(4):312-319
To characterize uremic cardiac autonomic neuropathy, we measured plasma catecholamines, analyzed the 24-hour heart rate variability (HRV), and acquired serial images with (123)I-metaiodobenzylguanidine (MIBG) in 44 patients with chronic renal failure on hemodialysis and in 14 controls. Time-domain measures were calculated using the Marquette HRV program. MIBG clearance rates from the heart and lung were evaluated on planar images, and the regional MIBG uptake in the left ventricular myocardium was evaluated with single-photon emission computed tomography. Compared with controls, plasma dopamine and norepinephrine levels were elevated (p < 0.001 and p = 0.03, respectively), and all the time-domain measures of HRV were reduced in the patients (p < 0.001). The MIBG clearance rate from the heart was higher (p < 0.001), that from the lung was lower (p < 0.001), and the myocardial MIBG distribution was more heterogeneous in patients than in controls (total uptake score p = 0.03). These variables were similar between 26 patients without and 18 patients with hypertension. Uremic cardiac autonomic neuropathy may be characterized by high plasma levels of dopamine and norepinephrine, reduced HRV, and abnormal MIBG kinetics in the heart with heterogeneous myocardial MIBG distribution, suggesting cardiac sympathetic overactivity and parasympathetic deterioration. In addition, abnormal MIBG kinetics in the lung may imply pulmonary sympathetic nervous dysfunction and/or endothelial dysfunction in uremic patients. 相似文献
45.
Koji Nakajima Hirohito Kubota Itaru Kato Kiyotaka Isobe Hiroo Ueno Kagehiro Kozuki Kuniaki Tanaka Naoko Kawabata Takashi Mikami Kosuke Tamefusa Ritsuo Nishiuchi Satoshi Saida Katsutsugu Umeda Hidefumi Hiramatsu Souichi Adachi Junko Takita 《Cancer science》2022,113(7):2472
Lineage switch is a rare event at leukemic relapse. While mostly known to occur in KMT2A‐rearranged infant leukemia, the underlying mechanism is yet to be depicted. This case report describes a female infant who achieved remission of KMT2A‐MLLT3‐rearranged acute monocytic leukemia, but 6 months thereafter, relapsed as KMT2A‐MLLT3‐rearranged acute lymphocytic leukemia. Whole exome sequencing of the bone marrow obtained pre‐post lineage switch revealed two somatic mutations of PAX5 in the relapse sample. These two PAX5 alterations were suggested to be loss of function, thus to have played the driver role in the lineage switch from acute monocytic leukemia to acute lymphocytic leukemia. 相似文献
46.
In rats, an injection of streptozotocin (STZ) elevated blood levels of glucose 4 weeks later (STZ-induced diabetes) and an over-production of microvessels of retinal and choroidal capillaries of eyes developed. A previous study has shown that administration of Stephania tetrandra S. Moore (STSM) in culture prevented the over-production of microvessels of those capillaries of STZ-induced diabetes in vitro. Therefore, the study investigated whether or not orally administered STSM could inhibit over-production of microvessels of those capillaries of STZ injected rats in vivo. When STSM was given at the same time as the STZ injection and continued daily for 7 weeks, STSM prevented the elevation of blood glucose level and over-production of microvessels of those capillaries. When STSM was given after elevation of blood glucose level of glucose (4 weeks after STZ injection) and continued daily for 4 weeks, STSM lowered the elevated blood glucose level but had no effect on the over-production of microvessels of those capillaries. It was inferred that deposition of N(epsilon)(carboxymethyl) lysine in retinal and choroidal tissues, which is induced by STZ-induced diabetes may deteriorate the blood-retinal barrier and the blood-choroidal barrier. One might, therefore, speculate that advanced STZ-induced diabetes may deteriorate the blood-retinal barrier and blood-choroidal barrier. Therefore, STSM may not reach the retinal and choroidal tissues in the posterior ocular region in vivo. 相似文献
47.
Iida T Yasuda M Miyazawa M Fujita M Osamura RY Hirasawa T Muramatsu T Murakami M Saito K Mikami M 《Archives of gynecology and obstetrics》2008,277(6):539-546
Material and methods We analyzed the expression of hypoxia inducible factor-1α (HIF-1α) and glucose transporter-1 (GLUT-1) by immunohistochemistry
in ovarian serous and mucinous tumors from the point view of the histological characteristics and acquisition of malignancy.
A total of 102 ovarian tumors were examined, composed of 31 adenomas (serous 17 and mucinous 14), 32 borderline tumors (serous
13 and mucinous 19), and 39 adenocarcinomas (serous 21 and mucinous 18).
Results The overall positive ratios were as follows: HIF-1α, 74% of
adenomas, 91% of borderline tumors, and 100% of adenocarcinomas; and GLUT-1, 68% of adenomas, 95% of borderline tumors, and
100% of adenocarcinomas. Comparing serous tumors and mucinous tumors, there was no significant difference in the positive
ratios of HIF-1α and GLUT-1 of adenomas, borderline tumors, and adenocarcinomas. However, both markers were more strongly
expressed in serous adenocarcinomas (HIF-1α, 3 + 100%; GLUT-1, 3 + 76%) than in mucinous adenocarcinomas (HIF-1α, 3 + 61%;
GLUT-1, 3 + 28%). The results of immunoblotting and mRNA expression level analyses corresponded with those of immunohistochemical
expression profiles. DNA binding assay also demonstrated that HIF-1 is more commonly activated in serous adenocarcinomas than
in mucinous adenocarcinomas.
Conclusion HIF-1α and GLUT-1 expressions seemed to be coordinated to adapt ovarian tumor cells into hypoxic conditions in close association
with the acquisition of malignancy. We consider that the relatively strong expression of both markers in serous tumors compared
with mucinous tumors is related to the difference in their histological characteristics. 相似文献
48.
Maeda N Osuga K Higashihara H Tomoda K Mikami K Nakazawa T Nakamura H Tomiyama N 《Cardiovascular and interventional radiology》2012,35(1):82-89
Purpose
The purpose of this retrospective study was to investigate the efficacy of transarterial chemoembolization (TACE) using cisplatin as a second-line treatment for advanced hepatocellular carcinoma (HCC) unresponsive to TACE using epirubicin–Lipiodol emulsion at our institution. 相似文献49.
50.
Perioperative Oral Administration of Cystine and Theanine Enhances Recovery After Distal Gastrectomy
Tomohiro Miyachi MD Takashi Tsuchiya MD PhD Atsushi Oyama MD PhD Takahiro Tsuchiya MD Naomi Abe RD Atsuko Sato RD Yasumasa Chiba MSc Shigekazu Kurihara PhD Tetsuro Shibakusa PhD Takashi Mikami BVSc 《JPEN. Journal of parenteral and enteral nutrition》2013,37(3):384-391
Background: It has been reported that cystine and theanine, amino acids related to glutathione synthesis, have immunomodulatory effects, such as suppressing inflammation after strenuous exercise. In this study, we examined the effects of oral administration of cystine and theanine during the perioperative period as a pilot study. Methods: Forty‐three cases of distal gastrectomy for cancer conducted in our department were assigned to the cystine and theanine group (CT group) or to the placebo control group (P group), and a randomized, single‐blind, parallel‐group study was then performed. Cystine (700 mg) and theanine (280 mg) or a placebo was administered to participants for 10 continuous days (4 days before to 5 days after surgery). Changes in pre‐ and postoperative interleukin (IL)–6, C‐reactive protein (CRP), albumin, white blood cell (WBC) count, neutrophil count, total lymphocyte count, resting energy expenditure (REE), and body temperature were compared and examined. Results: Ten patients were excluded, leaving 33 patients in the study. The CT group had significantly lower IL‐6 values (postoperative day [POD] 4), CRP levels (POD 7), neutrophil counts (POD 4), and body temperatures (POD 5) than the P group (P < .05). In addition, REE in the P group peaked on day 1 (1.14 ± 0.16 [pre‐ and postoperative ratio]), whereas the CT group did not show any increase on POD 1 (0.99 ± 0.21, P < .05 vs P group). Conclusions: This study suggests that oral administration of cystine and theanine during the perioperative period may alleviate postgastrectomy inflammation and promote recovery after surgery. 相似文献