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21.
We conducted a noninvasive near-infrared spectroscopy (NIRS) study using the game of rock, paper, scissors (RPS) as a simple neurocognitive task for the prefrontal cortex (PFC) in 15 healthy volunteers. We employed an opposite “to lose” RPS task coupled with a normal “to win” RPS task, since the former requires inhibition of behavior, one of the most important functions of the prefrontal cortex. During the NIRS examination, subjects had to present one of the three RPS hands in response to hands displayed randomly on a computer screen every 1.5 s, and were required to show hands that lose to the computer, or that beat the computer. We measured the relative concentrations of oxyhemoglobin (oxy-Hb) using the prefrontal probes of the NIRS system during the tasks. The increases in oxy-Hb during the “to win” RPS task were small, but were quite large and laterally dominant during the “to lose” RPS task. The difference between the two tasks might have been due to the participants’ cognitive conflict with losing on the RPS. We conclude that losing is better than winning on the RPS as a sensitive indicator in the NIRS examination of PFC.  相似文献   
22.
NO-1886对高糖高脂饲料喂养新西兰兔糖代谢的影响   总被引:6,自引:0,他引:6  
合成药NO-1886是脂蛋白脂肪酶(LPL)的激动剂,能降低血浆甘油三酯(TG)并升高高密度脂蛋白胆固醇(HDL-c)水平。我们曾发现NO-1886还具有降低血糖的作用。本研究主要观察NO-1886对糖尿病兔胰岛素抵抗及β-细胞功能方面的影响。用高糖高脂饲料诱导,使新西兰兔血浆葡萄糖升高,发生胰岛素抵抗。在高糖高脂饲料中添加1%NO-1886进行治疗。结果:发现NO-1886可抑制血清葡萄糖升高,经糖耐量和胰岛素敏感性试验检测,NO-1886可保护胰岛素的急性相分泌,增强胰岛素对葡萄糖的清除能力。研究结果提示NO-1886具有改善胰岛素抵抗、降低血糖的作用。  相似文献   
23.
Some chordomas have a very poor prognosis because of their aggressive growth nature, but the efficacy of repeat operations for these cases has not been well documented. This report concerns 3 patients with aggressive chordoma of the clivus, who underwent operations 6 to 12 times over a period of 8 to 17 years because of symptomatic regrowth. Overall mean interval between repeat operations was 18 months with a range from 5 to 57 months and survival times were 9 to19 years after the first surgery. Main symptoms before each operation were diplopia and visual disturbance. Repeat palliative operations by intentional extradural debulking of the tumour to decompress offending neural structures, as well as maximal removal of the tumour, using appropriate skull base approaches, can mitigate progressive symptoms, and may result in better quality and some prolongation of life, although our patients gradually deteriorated neurologically throughout the clinical course.  相似文献   
24.
A precision device was developed for quantitative measurement of the active and passive forces of the horizontal muscles in several different types of strabismus. The device consists of a tension gauge for measuring isometric muscle tension (active force) and passive length-tension (passive force), and a circular-motion guide mechanism. In normal subjects, the active force showed nearly linear changes with the eye position, as was reported in past studies. A similar relationship between the active force and the eye position was observed also in strabismus patients in our study. Normal subjects showed a stronger force in the medial than the lateral rectus muscle. Among strabismus patients, those with normal retinal correspondence (NRC)-intermittent exotropia showed a force closest to that of the normal controls. However, the force of the lateral rectus muscle was significantly greater in those with constant exotropia than in the normal controls. The active force of the medial rectus muscle was significantly smaller in those with dual retinal correspondence (DRC)-intermittent exotropia and constant exotropia. Conversely, the active force of the medial rectus muscle was significantly greater in those with esotropia, compared with the normal group. As for the passive force, there was no significant difference between the temporal passive force and the nasal passive force in the normal and esotropic groups, but the temporal passive force was significantly greater in the esotropic group. The magnitude of the force was greater in both directions when traction was applied against the muscle having the stronger active force. These results suggest that the lateral rectus muscle force is relatively stronger in patients with DRC-intermittent exotropia due to a weakness of the medial rectus muscle force, and that the absolute strength of the lateral rectus muscle force is increased in patients with constant exotropia, but in NRC-intermittent exotropia the muscle forces are almost normal. Those with esotropia are considered to have an absolute increase in the medial rectus muscle force.  相似文献   
25.
Abstract: The effects of pyridoxalated hemoglobin polyoxyethylene conjugate (PHP) and stroma-free hemoglobin (SFH) on vascular responsiveness to various vasoactive substances were examined in isolated perfused rat kidneys. The kidneys isolated from rats were perfused with 6% PHP, 6% SFH, and 6% hydroxyethylstarch (HES) solution at a constant flow rate. Vascular responsiveness to acetylcholine (ACh), nitroglycerin (NG), norepinephrine (NE), and angiotensin-II (ANG-II) was examined by measuring the perfusion pressure (PP). Effects of inhibition of endothelium-derived relaxing factor (EDRF) by NG-monomethyl L-arginine (L-NMMA) on NE-induced and ANG-II-induced renal vascular responses were examined. ACh and NG induced a dose-dependent decrease in perfusion pressure (PP) in all groups. NE and ANG-II induced an increase in PP in all groups, but NE-induced and ANG-II-induced responses in the PHP-perfused and SFH-perfused groups were significantly larger than those in the HES-perfused group. L-NMMA did not alter vascular responsiveness to NE and ANG-II. These results indicate that PHP and SFH do not inhibit EDRF induced by ACh, but hemoglobin moiety per se does augment the vascular responsiveness to NE and ANG-II in the isolated perfused rat kidney.  相似文献   
26.
The purpose of this study was to determine the relationship between segmental hyperintensity of the liver on T1-weighted images and segmental cholestasis in patients with obstructive jaundice. T1-weighted and T2-weighted MR images were obtained of 73 patients with obstructive jaundice caused by various diseases. Fat-suppressed T1-weighted images were also obtained of 10 patients. Eleven patients with segmental intra-hepatic bile duct dilatation (cholestasis) showed segmental hyperintensity on T1-weighted images and/or fat-suppressed T1-weighted images and no signal intensity difference on T2-weighted images. Sixty-two patients with widespread intrahepatic bile duct dilatation showed no intensity difference on T1-weighted and T2-weighted images (P < .01). Segmental hyperintensity on T1-weighted images was correlated with intrahepatic cholestasis.  相似文献   
27.
We reported movement-related cortical potentials (MRCPs) in 11 patients with lesion of the dentate nucleus (Machado-Joseph disease (MJD) 7 cases, dentato-rubro-pallido-luysian atrophy (DRPLA)1, myoclonus epilepsy associated with ragged-red fibers (MERRF)1, dyssynergia cerebellaris myoclonica (DCM) 2), and compared with those of 7 cases of multiple system atrophy (MSA) who were postulated to have mild dentate lesions (striato-nigral degeneration 2 cases, Shy-Drager syndrome 2, sporadic olivo-ponto-cerebellar atrophy 3), and 7 control subjects without any neurological findings. Further we classified the diseases into the following two groups based on the lesion of the dentate nucleus. One was MJD group that had normal or slightly abnormal electroencephalogram (EEG), and the other was DN group (DRPLA, MERRF, DCM) that had markedly abnormal EEG. One of the main findings from this study was smaller slope of the Ns' in the MJD and DN group and normal slope of BP. There was no significant difference in the slope of Ns' between MJD patients and DN patients. This result shows EEG abnormalities have no influence on MRCP recordings. These results suggest that Ns' component may reflect the function in the cerebellar dentate nucleus, and that MRCP is a useful diagnostic method in patients with cerebellar ataxia.  相似文献   
28.
The cause of aplastic anemia associated with hepatitis (AAH) is as yet still unknown. There is a supposed relation to the immune mechanisms, however few reports have shown the effects of monocytes on the pathogenesis in the patients with AAH. We have reported a case of a 12-year-old boy with AAH related to cytomegaloviruses, and studied the hemopoietic progenitors. He showed pancytopenia and hypoplasia of the bone marrow on admission to our hospital. The culture studies showed that mononuclear cells (MNC) of the bone marrow produced few hemopoietic colonies in all cell lineages. However, the depletion of adherent cells from the MNC increased numbers of erythroid, neutrophil-macrophage and megakaryocyte colonies. Furthermore, the addition of adherent cells of the peripheral blood suppressed the colony formation in the aforementioned cell lineages by marrow MNC from which adherent cells, phagocytic cells and T-cells were abrogated. The results way suggest that monocytes play some soles in the pathogenesis of aplasia through inhibitor of hemopoiesis.  相似文献   
29.
β2-glycoprotein-I (β2GPI) is a phospholipid-binding plasma protein that consists of five homologous domains. Domain V is distinguished from others by bearing a positively charged lysine cluster and hydrophobic extra C-terminal loop. β2GPI has been known as a natural anticoagulant regulator. β2GPI exerts anticoagulant activity by inhibition of phospholipid-dependent coagulation reactions such as prothrombinase, tenase, and factor XII activation. It also binds factor XI and inhibits its activation. On the other hand, β2GPI inhibits anticoagulant activity of activated protein C. According to the data from knockout mice, β2GPI may contribute to thrombin generation in vivo. Phospholipid-bound β2GPI is one of the major target antigens for antiphospholipid antibodies present in patients with antiphospholipid syndrome (APS). Binding of pathogenic anti-β2GPI antibodies increases the affinity of β2GPI to the cell surface and disrupts the coagulation/fibrinolysis balance on the cell surface. These pathogenic antibodies activate endothelial cells via signal transduction events in the presence of β2GPI. Impaired fibrinolysis has been reported in patients with APS. Using a newly developed chromogenic assay, we demonstrated lower activity of intrinsic fibrinolysis in euglobulin fractions from APS patients. Addition of monoclonal anti-β2GPI antibodies with β2GPI also decreased fibrinolytic activity in this assay system. β2GPI is proteolytically cleaved by plasmin in domain V (nicked β2GPI) and becomes unable to bind to phospholipids, reducing antigenicity against antiphospholipid antibodies. This cleavage occurs in patients with increased fibrinolysis turnover. Nicked β2GPI binds to plasminogen and suppresses plasmin generation in the presence of fibrin, plasminogen, and tissue plasminogen activator (tPA). Thus, nicked β2GPI plays a role in the extrinsic fibrinolysis via a negative feedback pathway loop.  相似文献   
30.
Wilms tumor gene (WT-1) expression has been reported in many human cancers, including most ovarian and peritoneal serous carcinomas, but has not been studied in carcinomas of the fallopian tube. In this study, the authors evaluated the immunohistochemical expression of WT-1 in serous carcinomas of the fallopian tube and compared their reactivity with that of ovarian, peritoneal, and endometrial serous carcinomas. All primary serous carcinomas of the fallopian tube (13 cases), ovaries (25 cases), and peritoneum (3 cases) were reactive with the WT-1 antibody, whereas all five primary endometrial serous carcinomas were nonreactive. WT-1 reactivity in an unknown primary serous carcinoma is therefore suggestive of an extrauterine site. The marked difference in WT-1 staining raises the possibility of genetic differences between serous carcinomas arising in the endometrium compared with those arising in the ovaries, fallopian tubes, and peritoneum.  相似文献   
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