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1.
Purpose Reelin is important in the guidance of neuronal stem cells in the central nervous system during normal development. We wished to determine whether reelin is expressed in the retina and cornea after injury. Methods Mice underwent laceration of their retina as well as corneal epithelial debridement. The mice were sacrificed at 3 days, and eyes were fixed and stained for reelin expression and reelin messenger ribonucleic acid (mRNA). Results In normal eyes, reelin was expressed only at very low levels in the ganglion cell layer of the retina and the endothelial cell layer of the cornea. In injured eyes, there was marked expression in reelin immunoreactivity in the retina and cornea. Reelin gene expression was seen in the retina and cornea. Conclusions Reelin is expressed during normal retinogenesis. This study shows that reelin is also upregulated following injury to the retina and cornea. The expression of reelin following injury suggests that reelin may play an important role in regulating stem cell trafficking in neuronal and nonneuronal tissues following injury similar to its role in normal organogenesis. For consideration of publication in Graefe’s Archive for Clinical and Experimental Ophthalmology.  相似文献   
2.
The spectral response curve (amplitude versus wavelength) of the R2 of the early receptor potential (ERP) was studied in normal, protan, and deutan subjects. The R2 amplitude peaked at 520nm in most normal subjects. The R2 at long wavelengths was smaller than normal in protans and larger than normal in deutans when the maximum amplitudes were normalized to 100% at the peak. The ratio of the R2 amplitude at 460 nm to that at 600 nm clearly differed between protans and deutans. The ERP and the rapid off-response, which is mainly due to the cessation of the late receptor potential, were recorded in the same subjects. The ratio of the sensitivity of the rapid off-response at 500 nm to that at 600 nm was correlated with the ratio of the R2 amplitude at 460 nm to that at 600nm (correlation coefficient, 0.823, p < 0.001). This study, in conjunction with our previous study, indicates that the abnormality is in the outer segments of the cones in protans and deutans.  相似文献   
3.
Because gastric cancers located in the upper third of the stomach are difficult to detect at an early stage, the surgical results remain poor. We performed R4 gastrectomy as a radical procedure for 25 patients, involving complete resection of the latero-aortic and interaorticovenous lymph modes above and below the left renal vein, in combination with the ordinary R2 or R3 gastrectomy (the R4 group). These patients were compared with 156 others who underwent R2 gastrectomy alone (the R2 group). There were no significant differences in operation time, blood loss, or the incidence of complications between the two groups; however, when the survival rates of the patients with tumors invading beyond the subserosa were compared, the 5-year survival rate was found to be significantly higher in the R4 group than in the R2 group. Furthermore, in patients with para-aortic nodal involvement, a significant survival advantage was observed in the R4 group, as compared with the R2 group. These results suggest that the R4 gastrectomy is a rational approach for patients with advanced gastric cancer located in the upper third of the stomach.  相似文献   
4.
The usefulness of carcinoembryonic antigen (CEA) as an indicator for recurrence and a guide to the treatment was evaluated from a retrospective analysis of 88 patients with recurrent gastric cancer. Sixty-two of these patients (70.5 per cent), 25 of whom had a preoperative positive assay, and 37 a negative assay, had elevated levels of CEA after disease progression. Averaged CEA level in patients with liver metastasis was significantly higher (872 ng/ml) than in those with peritoneal metastasis (68 ng/ml), with lymph node metastasis (103 ng/ml) or with local metastasis (93 ng/ml) (p<0.01). An elevation of CEA was found prior to the clinical manifestation of recurrence, and the average lead time was 4 months. In 25 patients with a lead time of more than 4 months, survival time after CEA elevation was 13.3 months, which was longer than the 6.5 months of 28 patients with less than 4 months. Thirty-seven of the 88 patients were treated after recurrence. The average survival period after the detection of recurrence was 9.4 months in patients with surgical treatments followed by chemotherapy, 5.9 months in those with chemotherapy alone and 3.8 months in those with surgery alone. The average survival period of 26 patients with positive CEA assays in recurrence was 5.1 months longer than of patients with negative assays. This fact suggested that early detection of recurrence followed by various treatments, in the elevated CEA group, contributes to favorable results.  相似文献   
5.
Gastric cancer heterogeneity   总被引:1,自引:0,他引:1  
This study was carried out on 222 samples from 37 gastric carcinomas to assess the incidence of multiple stem lines in primary tumors and metastasis as reflected by multiple DNA stem lines and their relationship to epidermal growth factor (EGF) receptor expression, histologic grade, tumor size, and degree of wall infiltration. Fifteen primary tumors (40.5%) were homogeneously diploid/peridiploid whereas 22 (59.5%) were aneuploid. In the lymph node metastasis, seven patients (29.2%) had an homogeneous diploid/peridiploid pattern in all metastatic lymph nodes. On the other hand, 17 (70.8%) had at least one aneuploid peak in the lymph node metastasis. DNA content heterogeneity was seen in 12 (33%) of primary tumors whereas 14 (66.6%) of 21 patients had multiple cell clones in the metastasis. Therefore, 12 patients had a metastatic clone which was not observed in the primary tumor. DNA content heterogeneity was seen even in tumors with submucosal invasion suggesting that this phenomenon is also present at earlier stages. No correlation between the histologic grade and the DNA distribution was observed. Furthermore, histologic heterogeneity was independent of DNA content heterogeneity. The EGF receptor expression was observed in six of the 23 patients in whom this analysis was done. The EGF receptor expression was constant in all samples which were studied and even samples with a different DNA content and histologic grade were stables for the EGF receptor expression.  相似文献   
6.
We presented here two patients with hemorrhagic infarction occurred during subacute phase of brain embolism. The patients were 71-year-old and 73-year-old men who suffered from brain infarction of the left posterior cerebral artery and right middle cerebral artery territory, respectively. Both of them were diagnosed as having cryptogenic stroke and patent foramen ovale. After transferred to rehabilitation hospitals taking aspirin for a secondary prevention of stroke, they developed hemorrhagic infarction at day 17 and day 19, respectively. Their blood pressure remained within normal range throughout acute and subacute phase. Although most of hemorrhagic infarction occurs within 24 hours of stroke onset, some patients develop symptomatic hemorrhagic infarction even after 10 days. We need to be careful about late-onset hemorrhagic infarction, because many patients are now transferred early to rehabilitation hospitals to facilitate dedicated systematic rehabilitation.  相似文献   
7.
We previously reported the hyperosmolarity response (a decrease of the ocular standing potential by hyperosmolarity) as a new clinical test of the retinal pigment epithelium (RPE) activity. In the present study a hypertonic solution (Fructmanit, 1.4 × 103 m0sm/1) was intravenously injected for 20 min in proportion to a subject's total blood volume (TBV). At the injection speed of 5, 10, and 15% of the subjects' TBV per hour the mean amplitude of the hyperosmolarity response in normal subjects was 19.7, 30.1 and 36.4% respectively. The amplitude of the hyperosmolarity response depends on the logarithm of the dose of the hypertonic solution within the range of the dose tested.We previously found that hyperosmolarity suppresses the light rise. The present study investigated this suppressive effect in a quantitative manner. The light rise (a full-field illumination of 1.2 × 103 cdl/m2) was dose-dependently suppressed by Fructmanit. The mean of the light rise to dark trough ratio in normal subjects was 1.81 with no osmotic stress, and 1.64, 1.41 and 1.29 respectively at the injection speeds of 5, 10, and 15%. The suppression of the light rise by hyperosmolarity is compatible with the view that the hyperosmolarity response and the light rise share the basal membrane of the RPE as the main site of their generation.  相似文献   
8.
Analysis of DNA ploidy patterns was performed on 76 diffusely infiltrating carcinomas of the stomach and the results correlated with histologic findings and outcome. Twenty six cases were diploid (34%) and 50 cases were aneuploid. There was no correlation between DNA ploidy and histologic type, depth of invasion, lymphatic invasion, evidence of peritoneal dissemination or curability. In aneuploid tumors, incidence of vascular invasion was significantly higher than that in diploid tumors (p less than 0.05). In addition, the patients with aneuploid tumors had a poor prognosis than with diploid tumors. These results indicate that DNA ploidy patterns may possibly be a useful prognostic marker for diffusely infiltrating carcinomas of the stomach.  相似文献   
9.
To elucidate the mechanism that produces enormous molecular diversity in troponin T (TnT) of fast skeletal muscle, we determined the 5-half genomic sequence of the chicken fast muscle TnT gene. The sequence of ca. 16 kb included seven exons (exons 1, 2, 3, 4, w, 5, and 6), which have been reported previously and presumed by sequencing TnT cDNAs. Additionally we found six 15 nt and one 18 nt sequences in the region between exons 5 and 6 (i.e. the exon x region). They were encompassed by consensus splice donor and acceptor sites and preceded by putative branch sites, and designated herein as exons xa to xg. Our result shows that the sequence derived from exons x1, x2, and x3, the exons presumed previously by cDNA sequencing, is actually encoded by the seven exons xa to xg, establishing the precise gene structure in the exon x region. Based on our data, together with that on the 3-half genomic sequence of the quail fast muscle TnT gene, we conclude that the avian fast skeletal muscle TnT gene includes 27 exons, 16 of which are alternatively spliced.  相似文献   
10.
Bone marrow stem cells develop into haematopoietic and mesenchymal lineages, but have not been known to participate in steroidogenic cell production. Steroidogenic factor 1 (SF-1), also designated adrenal 4 binding protein (Ad4BP), is an essential orphan nuclear receptor for steroidogenesis as well as for adrenal and gonadal gland development. In the present study, we revealed that the adenovirus-mediated forced expression of SF-1 can transform cultured primary long-term cultured bone marrow cells into steroidogenic cells, showing the de novo synthesis of multiple steroid hormones in response to adrenocorticotropic hormone (ACTH). This finding may provide an initial step in innovative autograft cell transfer therapy for steroid hormone deficiencies.  相似文献   
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