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101.
In the cirrhotic and precirrhotic liver, there may be small foci with increased cellularity and amphophilic cytoplasm. These are microscopic lesions that do not form macroscopically detectable nodules, which differ from the macroscopically apparent nodules of dysplastic nodules. In the present study, we assessed the proliferating activity of 12 hyperplastic foci in 11 patients with cirrhosis or chronic hepatitis, by staining for agyrophilic nucleolar organizing regions (AgNOR). The mean AgNOR count per nucleus in the hyperplastic foci ranged from 0.96 to 1.36 (mean, 1.13; SD 0.12), and from 0.81 to 1.06 (mean, 0.94; SD 0.08) in the controls. The AgNOR count In the hyperplastic foci was significantly higher than that In the controls (P> 30.01). Small hyperplastic foci show Increased proliferative activity. Further study on these foci is required to clarify their relation to hepatocarcinogenesis.  相似文献   
102.
We characterized the visual pathways involved in the stereoscopic recognition of the random dot stereogram based on the binocular disparity employing a functional magnetic resonance imaging (fMRI). The V2, V3, V4, V5, intraparietal sulcus (IPS) and the superior temporal sulcus (STS) were significantly activated during the binocular stereopsis, but the inferotemporal gyrus (ITG) was not activated. Thus a human M pathway may be part of a network involved in the stereoscopic processing based on the binocular disparity. It is intriguing that areas 44 (Broca's area) and 45 in the left hemisphere were also active during the binocular stereopsis. However, it was reported that these regions were inactive during the monocular stereopsis. To separate the specific responses directly caused by the stereoscopic recognition process from the nonspecific ones caused by the memory load or the intention, we designed a novel frequency labeled tasks (FLT) sequence. The functional MRI using the FLT indicated that the activation of areas 44 and 45 is correlated with the stereoscopic recognition based on the binocular disparity but not with the intention artifacts, suggesting that areas 44 and 45 play an essential role in the binocular disparity.  相似文献   
103.
BACKGROUND: Eating disorders are thought to be risk factors for cardiac sudden death secondary to arrhythmia. Results in previous studies on QT interval and QT dispersion, markers of fatal arrhythmia, have been inconsistent. METHODS: We prospectively examined 179 female eating disorder patients, being over 18 years old and diagnosed according to the DSM-IV criteria between January 1995 and December 2002, and 52 healthy women. Patients with abnormal plasma electrolytes or taking medications that might influence the electrocardiogram (ECG) were excluded from the study. QT intervals were corrected for heart rate using Bazett's formula and the nomogram method, which is more reliable at extremely low heart rates than Bazett's formula. QT dispersion was measured as the difference between the longest and shortest QT intervals. QT intervals and QT dispersion in each patient group were compared with those in the control group. RESULTS: The 164 eligible patients consisted of 43 patients with anorexia nervosa restricting type, 35 with anorexia nervosa binge eating/purging type, 63 with bulimia nervosa purging type, and 23 with bulimia nervosa non-purging type. There was no significant difference in age between eating disorder patients and controls. QT interval and QT dispersion were significantly longer in all eating disorder subtypes than in the control group. QT interval and QT dispersion were significantly correlated with the rate of body weight loss in bulimia nervosa. CONCLUSIONS: QT interval and QT dispersion were prolonged in both anorexia nervosa and bulimia nervosa. Examination of ECG in eating disorder patients without extremely low body weight also appears to be clinically important.  相似文献   
104.
Objective: The aims of the present study were to elucidate the interaction of reactive oxygen species (ROS) and Ca2+ response in central nervous system (CNS) pericytes. Methods: The intracellular Ca2+ concentration was measured using fluorescent Ca2+ indicator, fura-2, in cultured CNS pericytes. Results: Hydrogen peroxide evoked a dose-dependent increase in cytosolic Ca2+, which was completely inhibited by catalase. Removal of external Ca2+ or addition of nicardipine (1 μM) during application of hydrogen peroxide did not affect Ca2+ response. Incubation of the cells in Ca2+ free solution did not abolish but slightly reduced Ca2+ response by hydrogen peroxide. Ca2+ response to hydrogen peroxide was not altered by the depletion of intracellular Ca2+ by thapsigargin (1 μM). Pretreatment of the cells with tyrosine kinase inhibitor genistein (100 μM) or tyrphostin A47 (30 μM) significantly reduced Ca2+ increase by hydrogen peroxide. Conclusions: These results indicate that hydrogen peroxide evokes Ca2+ increase predominantly by release from intracellular Ca2+ store, which may be regulated by tyrosine kinases.  相似文献   
105.
The test method of "activated sludge, respiration inhibition test" proposed by the OECD was critically carried out and compared with other test methods. Investigation of test conditions showed that the moderate deviation from the test conditions defined by the OECD Test Guidelines did not have much effect on the result, and some modifications were proposed to improve the method. This method had a poor detection limit compared with the LC50 test with Oryzias latipes and EC50 of the growth inhibition test with Tetrahymena pyriformis. The susceptivity of the method was particularly poor for the chemicals which were highly toxic in the other two tests.  相似文献   
106.
The androgens testosterone and dihydrotestosterone (DHT) are essential for a variety of systemic functions in mature males. Alteration of these hormones results in late-onset hypogonadism (LOH) and benign prostate hyperplasia (BPH). The fruit bodies of fungi of the genus Cordyceps have been regarded as folk medicine or health food with tonic and antifatigue effects. The extract from the fruit body of Cordyceps militaris parasitizing Samia cynthia ricini (CM) was evaluated as a novel-candidate natural product for ameliorating male andropause symptoms. To explore the effects of CM on LOH and BPH, CM was applied to rat models and cultured testicular cells and prostate cells. The concentrations of androgens in the serum and culture media were determined by ELISA. Expression of steroidogenic enzymes and androgen-related genes was evaluated by qPCR, and prostatic cell proliferation was assessed with the cell-viability assay. CM maintained the serum levels of testosterone and DHT, but inhibited testosterone-induced prostate hypertrophy. CM also increased the secretion of testosterone and DHT by primary testicular cells, with no changes in the mRNA expression of steroidogenic enzymes, but decreased the growth of prostatic cell lines. Our data suggest that CM could improve both LOH and BPH in males.  相似文献   
107.
The European Journal of Health Economics - We examine the relationship between Internet-based health information seeking and the demand for physician services, using data collected from the 28...  相似文献   
108.
109.
Bevacizumab (BEV) is a key anti-angiogenic agent used in the treatment for recurrent glioblastoma multiforme (GBM). The aim of this study was to investigate whether cytoreductive surgery prior to treatment with BEV contributes to prolongation of survival for patients with recurrent GBM. We retrospectively analyzed the treatment outcomes of 124 patients with recurrent GBM who were initially treated with the Stupp protocol between 2006 and 2019. Given that BEV has only been available in Japan since 2013, we grouped the patients into two groups according to the time of first recurrence: the pre-BEV group (N = 51) included patients who had recurrence before BEV approval, and the BEV group (N = 73) included patients with recurrence after BEV approval. The overall survival after first recurrence (OS-R) was analyzed according to the treatment strategy. Among 124 patients, 27 patients (19.4%) received cytoreductive surgery. There were nine cases in the pre-BEV group and 18 cases in the BEV group. Although the mean extent of resection for both groups was almost equal, OS-R was significantly different. The median OS-R was 8.1 m in the pre-BEV group and 16.3 m in the BEV group (P = 0.007). Multivariate analysis revealed that the unavailability of BEV postoperatively (P = 0.03) and decreasing performance status by surgery (P = 0.01) were significant poor prognostic factors for survival after surgery. With the advent of BEV, cytoreductive surgery might provide superior survival benefit at the time of GBM recurrence, especially in cases where surgery can be performed without deteriorating the patient’s condition.  相似文献   
110.
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