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101.
目的:生命早期阶段的骨密度值是预测后期骨骼状况的最佳指标。通过调查分析延吉市小学生生活习惯与骨密度关系,为提高小学生骨密度,以早期达到骨峰值量,防止日后的骨质疏松提供参考。 方法:使用青少年骨密度影响因素调查表,对2005-10/2006-01延吉市802名6~15岁朝鲜族、汉族小学生进行关于一般情况的调查以及运动史、睡眠和休养状况、饮食生活习惯等的问卷调查,并用超声波骨密度测定仪(AOS-100) 进行右脚跟骨的骨密度值测量,根据伟导速度和透过指数,计算出综合骨评价值,将有关的调查结果进行统计学处理。 结果:①调查结果一般情况:有效回答问卷率为97.9%(785名),其中朝鲜族395名,男生240名,女生155名;汉族390名,男生207名,女生183名。两民族之间的年龄及年龄构成经检验均无统计学意义。②体质量指数及骨密度:朝鲜族的体质量指数高于汉族(P < 0.05),朝鲜族的骨密度也高于汉族(P < 0.001)。③运动与骨密度关系:经常参加运动者的骨密度高于不经常参加运动者(P < 0.05)。④睡眠和休养状况与骨密度关系:睡眠质量优者骨密度高于睡眠质量差者(P < 0.05)。⑤饮食习惯对骨密度的影响:汉族经常摄取豆制品者骨密度高于不摄取者(P < 0.001)。 结论:不同民族骨密度有差异;加强体育运动、提高睡眠质量与良好的饮食习惯可增加骨密度。  相似文献   
102.
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   
103.
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   
104.
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106.
We evaluated the acute toxicities of the main degradation products of pyridine triphenylborane (PTPB), namely, diphenylborane hydroxide (DPB), phenylborane dihydroxide (MPB), phenol, and biphenyl, to the alga Skeletonema costatum, the crustacean Tigriopus japonicus, and two teleosts, the red sea bream Pagrus major and the mummichog Fundulus heteroclitus. DPB was the most toxic of the degradation products to all four organisms. The acute toxicity values of DPB for S. costatum, T. japonicus, red sea bream, and mummichog were 55, 70, 100, and 200–310 μg/L, respectively. The degradation products were less toxic than PTPB to S. costatum and T. japonicus; however, the toxicities of DPB and PTPB to the fish species were similar. We also examined changes in the inhibition of growth rate of S. costatum as well as the percentage of immobilization of T. japonicus as end points of toxicity of PTPB after irradiation of PTPB with 432 ± 45 W/m2 of 290–700 nm wavelength light. After 7 days of irradiation with this light, the concentration of PTPB in the test solutions decreased markedly. A decrease in toxic effects closely coincided with the decrease in the concentration of PTPB caused by the irradiation. PTPB probably accounted for most of the toxicity in the irradiation test solutions. Because the concentrations of PTPB that were acutely toxic to S. costatum and T. japonicus were <10 % of the corresponding concentrations of its degradation products, PTPB probably accounted for most of the toxicity in the irradiation test solutions.  相似文献   
107.
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.
JTK-853, a palm site-binding NS5B nonnucleoside polymerase inhibitor, shows antiviral activity in vitro and in hepatitis C virus (HCV)-infected patients. Here, we report the results of genotypic and phenotypic analyses of resistant variants in 24 HCV genotype 1-infected patients who received JTK-853 (800, 1,200, or 1,600 mg twice daily or 1,200 mg three times daily) in a 3-day monotherapy. Viral resistance in NS5B was investigated using HCV RNA isolated from serum specimens from the patients. At the end of treatment (EOT) with JTK-853, the amino acid substitutions M414T (methionine [M] in position 414 at baseline was replaced with threonine [T] at EOT), C445R (cysteine [C] in position 445 at baseline was replaced with arginine [R] at EOT), Y448C/H (tyrosine [Y] in position 448 at baseline was replaced with cysteine [C] or histidine [H] at EOT), and L466F (leucine [L] in position 466 at baseline was replaced with phenylalanine [F] at EOT), which are known to be typical resistant variants of nonnucleoside polymerase inhibitors, were observed in a clonal sequencing analysis. These substitutions were also selected by a treatment with JTK-853 in vitro, and the 50% effective concentration of JTK-853 in the M414T-, C445F-, Y448H-, and L466V-harboring replicons attenuated the susceptibility by 44-, 5-, 6-, and 21-fold, respectively, compared with that in the wild-type replicon (Con1). These findings suggest that amino acid substitutions of M414T, C445R, Y448C/H, and L466F are thought to be viral resistance mutations in HCV-infected patients receiving JTK-853 in a 3-day monotherapy.  相似文献   
109.
110.
The purpose of this study was to evaluate the durability of one-bottle self-etching adhesive during long-term water-storage testing. Resin–dentin bonded specimens were prepared using four commercially available one-bottle self-etching adhesives. The specimens were sectioned perpendicular to the adhesive interface to produce beam-shaped specimens that were stored in water for 24 h (control group) and 100, 200, and 300 d (experimental groups). After each storage period, the beams were subjected to a microtensile bond test. After the bond test, fractured surfaces were examined using a scanning electron microscope. In addition, interfacial observations of the silver tracer were performed using the secondary and back-scatter modes of the scanning electron microscope. The bond strength of all tested adhesives decreased significantly after 100 or more days in water. The interfacial observations showed an oxygen-inhibition zone as electron lucent in the adhesive–composite border in control specimens, displaying silver impregnation with breakage after aging. The deterioration of the oxygen-inhibition zone in the adhesive–resin composite junction resulted in a decrease in bond strength after 100 d in water for one-bottle self-etching adhesives.  相似文献   
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