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Effects of dominant and nondominant eyes in binocular rivalry.   总被引:1,自引:0,他引:1  
PURPOSE: To investigate the relation between sighting and sensory eye dominance and attempt to quantitatively examine eye dominance using a balance technique based on binocular rivalry. METHODS: The durations of exclusive visibility of the dominant and nondominant eye target in binocular rivalry were measured in 14 subjects. The dominant eye was determined by using the hole-in-card test (sighting dominance). In study 1, contrast of the target in one eye was fixed at 100% and contrast of the target in the other eye was varied from 100% to 80% to 60% to 40% to 20%, when using rectangular gratings of 1, 2, and 4 cycles per degree (cpd) at 2 degrees, 4 degrees , and 8 degrees in size. In study 2, contrast of the target in the nondominant eye was fixed at 100% and contrast of the target in the dominant eye was varied from 100% to 80% to 60% to 40% to 20%, when using a rectangular grating of 2 cpd at 4 degrees in size. RESULTS: In study 1, the total duration of exclusive visibilities of the dominant eye target; that is, the target seen by the eye that had sighting dominance was longer compared with that of the nondominant eye target. When using rectangular gratings of 4 cpd, mean total duration of exclusive visibility of the dominant eye target was statistically longer than that of the nondominant eye target (p < 0.05). In study 2, reversals (in which duration of exclusive visibility of the nondominant eye becomes longer than the dominant eye when the contrast of the dominant eye target is decreased) were observed for all contrasts except for 100%. CONCLUSIONS: The dominant sighting eye identified by the hole-in-card test coincided with the dominant eye as determined by binocular rivalry. The contrast at which reversal occurs indicates the balance point of dominance and seems to be a useful quantitative indicator of eye dominance to clinical applications.  相似文献   
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MRI of ossification of ligamentum flavum.   总被引:11,自引:0,他引:11  
Magnetic resonance imaging of 28 patients with radiological and/or histopathologically proved ossification of the ligamentum flavum (OLF) was reviewed. The locations of OLF were cervical (n = 4), thoracic (n = 22), and lumbar (n = 2). On T1- and T2-weighted images, OLF demonstrated low signal intensity. Areas of high or intermediate signal intensity within the OLF on T1-weighted images were observed in three cases and were interpreted to be due to fat infiltration. In six cases, high intensity areas in the spinal cord caused by compressing OLF were demonstrated on T2-weighted images. Gadolinium-diethylenetriamine pentaacetic acid, which was used in four cases, showed cord enhancement at the level of compression by OLF in three cases.  相似文献   
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To evaluate the correlation between the histological grade and the prognosis, we reviewed 100 cases of prostatic cancer according to the Japanese General Rules of Prostatic Cancer (JGRPC) and Gleason grading system. The study led to the following results: (1) There was a close relation between the JGRPC grade and Gleason score (GS). (2) The JGRPC grade and Gleason score were equally concerned with the clinical stage. (3) There were significant differences in survival rate between well and moderately, well and poorly differentiated groups by the JGRPC grading system, and between GS 2-4 and GS 5-7, GS 2-4 and GS 8-10 groups by Gleason score. (4) In proportion to the JGRPC grade, the cancer death rate increased linearly in each stage. (5) When the patients were grouped according to their JGRPC grades of main lesion and accompanied lesion, the cancer death rate increased in the cases with lower differentiated elements. We conclude that the JGRPC grading system is easily comprehensible, and equal with the Gleason grading system to predict the prognosis of prostatic cancer.  相似文献   
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Low-dose γ-irradiation of mouse embryonic fibroblast C3D2F1 3T3-a cells caused Gl arrest along with G2 arrest and inhibition of replicative DNA synthesis. When the cells were cultured in the presence of inhibitors of poly(ADP-ribose) polymerase [EC 2.4.2.30], such as 3-aminobenzamide, benzamide and luminol, Gl arrest of C3D2F1 3T3-a cells was suppressed and enhancement of G2 arrest was observed. In contrast, 3-aminobenzoic acid, a non-inhibitory analog of 3-aminobenzamide, did not suppress Gl arrest following γ-irradiation. These results suggest that the poly(ADP-ribosyDation reaction is critical for the pathway of Gl arrest and is also involved in the pathway of G2 arrest.  相似文献   
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Abstract: Since April 1991, we have studied 160 patients who had had a successful laparoscopic cholecystectomy. Nine patients who presented with chronic cholecystitis with severe local adhesion and who were also considered to require a longer operative time were selected as suitable candidates for this procedure. They were successfully treated under a zero- to four-mmHg low-pressured pneumoperitoneum procedure combined with total abdominal wall lifting using a disposable, flexible vinyl tube retractor. This method enabled exactly the same clear laparoscopic vision as is possible in the routinely-used high-pressure pneumoperitoneum even in the marginal portions of the abdominal cavity. Moreover, it facilitated early reinsufflation after the cauterization-produced smoke was exhausted, which minimized the operative time and reduced the surgeon's anxiety concerning the maintenance of a sufficiently airtight condition. We believe that this low-pressure pneumopeqitoneum procedure also benefits the poor-risk patient who has restricted cardiopulmonary function, especially during advanced laparoscopic surgery which requires a longer operative and anesthetic time.  相似文献   
9.
Patients with Peutz-Jeghers syndrome (PJS) are known to be at risk of gastric cancer (GC), and the STK11 gene is a susceptibility gene for PJS. However, as no cases of PJS with GC in which a STK11 germline mutation has been identified have ever been reported and other susceptibility genes have also been suggested to be involved in PJS, the relation between STK11 germline mutations and GC in PJS is still unknown. In this study, we used sequencing analysis to investigate the STK11, CDH1, and TP53 loci for a germline mutation in two siblings with PJS with primary GC. A novel type of the STK11 germline mutation, c.890delG, encoding a truncated protein (p.Arg297fsX38) was identified, but no germline mutations of the CDH1 and TP53 genes were detected. No inactivation of the wild-type allele by somatic mutation or chromosomal deletion or hypermethylation at the 5'-CpG site of STK11 was detected in the GC. This is the first report of a STK11 germline mutation in a PJS patient with GC and should contribute to establishing correlations between the STK11 germline mutations and GC in PJS patients.  相似文献   
10.
Gastrointestinal tract tumours are notorious for their difficulty in relation to conventional cytogenetic analysis. In particular, necrosis, the presence of stromal inflammatory and other cells, and poor attachment of tumour cells have led to problems with the quality and reliability of cytogenetic preparations, even with the recently developed fluorescence in situ hybridisation (FISH) technique. Furthermore, background autofluorescence masks the weak hybridisation signals in the nuclei. To overcome this problem, brief microwave treatment was applied for the identification of centromeres by in situ hybridisation in gastric cancer cells. Using this technique, a panel of 17 centromeric specific alpha-satellite probes was used to detect chromosomal instability in these cells. Lymphocyte controls and cancer cells subjected to irradiation achieved the hybridisation threshold in 30 minutes, providing a significant difference when compared with the non-irradiated samples (mean (SD) frequency of diploid cells 97% (2.1%) v 76% (4.6%), respectively). Therefore, this protocol of intermittent microwave treatment is recommended as a simple, rapid, and highly reproducible technique for application to various types of probe. It also gives well defined hybridisation signals and reduces background "noise".  相似文献   
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