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101.
PurposeTo determine the shape of posterior staphylomas using ultra-widefield optical coherence tomographic (UWF-OCT) images and to identify the factors contributing to the shape and grade of the staphylomas in eyes with pathologic myopia.MethodsThis was an observational case series study. Highly myopic patients who were ≥40 years old with wide or narrow type of macular staphylomas were studied. High myopia was defined as a myopic refractive error (spherical equivalent) greater than −8.0 diopters (D) or an axial length (AL) > 26.5 mm. The maximum diameter and depth of the staphylomas were measured in the 12 radial scans of UWF-OCT images by ImageJ software and were compared between the two types of staphylomas.ResultsWe studied 197 eyes of 138 patients with a mean age of 64.7 ± 10.4 years and mean AL of 30.0 ± 1.9 mm. The AL was significantly longer in the eyes with the narrow type than the wide type of staphyloma (P = 0.036). Multiple regression analyses showed that age was significantly correlated with the maximum depth/maximum diameter ratio (wide type, P < 0.001; narrow type, P = 0.003) of both types of staphylomas. The AL was significantly correlated with the depth/diameter ratio of only the narrow type of staphylomas (P = 0.005).ConclusionsThe significant correlations of age and AL with the wide and narrow types of posterior staphylomas indicate that the factors for their formations may be distinctly different. Quantitative analyses of UWF-OCT images are helpful in determining the shape of the staphylomas.  相似文献   
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This is a report of a 63-year-old Japanese woman with a nonfunctioning islet cell carcinoma of the pancreas presenting bleeding gastric varices and splenomegaly. These manifestations are extremely rare in patients with nonfunctioning islet cell tumor. The tumor originated in the tail of the pancreas and grew mainly within the spleen. The gastric varices due to increased blood flow to the tumor and arteriovenous fistuals within the tumor were confirmed by angiography and operation. The tumor was resected and she is in a good health for 14-months after the operation.  相似文献   
104.
Evaluation of extensive lymph node dissection for carcinoma of the stomach   总被引:10,自引:0,他引:10  
We compared the results of curative resection for carcinoma of the stomach in 254 patients who underwent simple resection (SR) and 454 patients who underwent extensive regional lymph node dissection (ELD). The 5-year survival rates of the 2 procedures were significantly different in carcinoma involving the serosa of the stomach; it was 45% in the ELD group and 18% in the SR group (p<0.001). In patients with regional lymph node metastasis we obtained a 5-year survival rates of 39% and 18% by ELD and SR, respectively (p<0.001). The incidence of metastasis to the secondary lymph nodes, removable only by ELD, was higher in cases with carcinomatous invasion of the deeper layers of the gastric wall, and this may have been the reason why ELD proved to be more effective than SR. ELD is discussed in relation to the site of the primary carcinoma and the extent of lymph node metastasis.  相似文献   
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Abstract

Background: Test 1 is a recently introduced technique claiming to determine Erythrocyte Sedimentation Rate (ESR) in 20 s. In contrast to the original Westergren procedure this new technique uses undiluted blood and operates at 37°C. It is hypothesized that Test 1 is in fact an erythrocyte aggregometer and does not measure any sedimentation. Methods: Test 1 results were compared to those obtained with StaRRsed, an automated ESR analyser based on the Westergren technique, and the results of both were correlated to various indices of red blood cell (RBC) aggregation, obtained with an aggrego - meter (LORCA). Measurements were made on blood from 75 patients with various rheumatic disorders. Furthermore, blood that was experimentally manipulated in order to affect RBC aggregation, i.e. by changing the hematocrit, by diminishing plasma protein concentration, by inducing hyperaggregation or by RBC rigidification, was tested on all three instruments. Results: Generally in patient blood, Test 1 results demonstrated a higher correlation with the various aggregation parameters than StaRRsed. Highest correlation (R = ?0.8)) with both Test 1 and StaRRsed outcome were seen with I20, a RBC aggregation parameter directly related to the backscatter intensity. All experimentally induced changes in RBC aggregation paralleled closely those obtained with Test 1 while StaRRsed results followed a different course. Conclusions: The results obtained in this study strongly support the hypothesis that Test 1 measures only the RBC aggregation process and does not cover any of the indices directly linked to the sedimentation process as determined by the Westergren method.  相似文献   
108.
The role of insulin in controlling gastric inhibitory polypeptide (GIP) release was assessed in seven totally pancreatectomized patients, in whom inhibitory effects of endogenous pancreatic hormones on GIP secretion were excluded. In these patients, glucose was ingested on two occasions, once alone and once during insulin infusion using an artificial endocrine pancreas to maintain blood glucose at levels similar to those in normal subjects. Plasma levels of GIP, the maximum response of plasma GIP, and the integrated incremental GIP for 180 min were similar. We conclude that insulin does not alter the secretion of GIP in response to oral glucose when the influence of endogenous pancreatic hormones is excluded.  相似文献   
109.
BACKGROUND: High glucose reportedly stimulates prostaglandin (PG) E2 production and DNA synthesis in mesangial cells (MCs). However, the pathophysiological significance of PGE2 in MCs has remained unclear. METHODS: The effects of prostanoids on [3H]-thymidine uptake and cAMP production in rat MCs cultured with 5.6 mM glucose, 25 mM glucose, or 5.6 mM glucose supplemented with 19.4 mM mannitol were examined. The gene expression of PGE2 receptor (EP) subtypes in MCs was analyzed with Northern blotting techniques. RESULTS: Northern blotting indicated EP1 and EP4 gene expression in MCs. EP1 agonists and PGE2 stimulated [3H]-thymidine uptake in MCs. EP1 antagonists dose dependently attenuated high-glucose-induced [3H]-thymidine uptake, which suggests EP1 involvement, by an increase in intracellular Ca2+, in DNA synthesis of MCs. On the other hand, forskolin, db-cAMP, and 11-deoxy-PGE1, an EP4/EP3/EP2 agonist, significantly decreased DNA synthesis in MCs. These inhibitory effects are thought to be mediated via EP4 as a result of an increase in cAMP synthesis. The effects via EP4 seem to be particularly important because PGE2-induced cAMP synthesis was significantly attenuated in the high-glucose group compared with the mannitol group, in which [3H]-thymidine uptake did not increase in spite of augmented PGE2 production. CONCLUSION: The increase in DNA synthesis in MCs under high-glucose conditions can be explained, at least in part, by the high-glucose-induced inhibition of cAMP production via EP4, which augments EP1 function in conjunction with the overproduction of PGE2.  相似文献   
110.
To understand the role of agouti-related protein (AGRP), an endogenous antagonist of hypothalamic melanocortin receptor, in leptin action, we produced a full-length recombinant AGRP and examined its effect on the satiety effect of leptin. We also studied leptin's regulation of hypothalamic AGRP mRNA expression. A single intracerebroventricular (i.c.v.) injection of AGRP significantly increased cumulative food intake and body weight in a dose-dependent manner in rats. The leptin-induced inhibition of food intake and body weight was reversed by co-injection of AGRP in a dose-dependent manner. Hypothalamic AGRP mRNA expression was upregulated in leptin-deficient ob/ob mice and leptin receptor-deficient db/db mice and downregulated in lethal yellow agouti mice (KKAy mice) with hyperleptinemia. A single i.c.v. injection of leptin reversed the increased AGRP mRNA levels in ob/ob mice but not in db/db mice. In control mice and KKAy mice, AGRP mRNA expression was upregulated during fasting, when plasma leptin concentrations were decreased. No significant increase in AGRP mRNA expression was noted during fasting in control mice and KKAy mice treated with leptin. This study provides the first direct evidence that AGRP is a negative regulator of leptin action, and leptin downregulates hypothalamic AGRP production. Because leptin is shown to increase hypothalamic alpha-melanocyte stimulating hormone (alpha-MSH) production, our data suggest that its action via the hypothalamic melanocortin system is determined by the balance between the levels of its agonist and antagonist, alpha-MSH and AGRP.  相似文献   
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