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51.
Drs Hideo Tanaka Drs Tomohiko Hiyama Drs Hideaki Tsukuma Drs Yasuto Okubo Drs Hajime Yamano Drs Akira Kitada Drs Isaburo Fujimoto 《Cancer causes & control : CCC》1994,5(5):409-413
To clarify the demographic characteristics of the prevalence of hepatitis C virus (HCV) infection in Osaka, Japan, where hepatocellular carcinoma is common, we investigated the screening data of antibody to HCV (anti-HCV, DAINABOTHCVPHA, second generation assay) in 197,600 voluntary blood donors residing in Osaka. The study found that age-standardized prevalence of anti-HCV was significantly higher than that of HBsAg (2.25cf 0.86 percent among males,P<0.001; 2.17cf 0.55 percent among females,P<0.001. It was much higher in the blood donors aged 55–64 years than in those aged 16–54 years (8.49cf 1.32 percent among males,P<10–5; 7.26cf 1.42 percent among females,P<10–5). The prevalence of anti-HCV among males was significantly higher than that of females in the younger (25–34 years) generations (1.02 to 1.49 percentcf 0.71 to 1.13 percent,P<0.05). A similar tendency was observed in the prevalence of high-titer (212) anti-HCV. The number of coinfection (both HBsAg and anti-HCV seropositive) was very small, and it was not statistically different from the expected number. 相似文献
52.
The forward problem of a new medical imaging system is analysed in this study. This system uses magnetic excitation to induce currents inside a conductive body and measures the magnetic fields of the induced currents. The forward problem, that is determining induced currents in the conductive body and their magnetic fields, is formulated. For a general solution of the forward problem, the finite element method (FEM) is employed to evaluate the scalar potential distribution. Thus, inhomogeneity and anisotropy of conductivity is taken into account for the FEM solutions. An analytical solution for the scalar potential is derived for homogeneous conductive spherical objects in order to test FEM solutions. It is observed that the peak error in FEM solutions is less than 2%. The numerical system is used to reveal the characteristics of the measurement system via simulations. Currents are induced in a 9x9x5 cm body of conductivity 0.2 S m(-1) by circular coils driven sinusoidally. It is found that a 1 cm shift in the perturbation depth reduces the field magnitudes to approximately one-tenth. In addition, the distance between extrema increases. Further simulations carried out using different coil configurations revealed the performance of the method and provided a design perspective for a possible data acquisition system. 相似文献
53.
An experimental study of the effects of nerve root retraction on the posterior ramus 总被引:7,自引:0,他引:7
STUDY DESIGN: The histologic and ultrastructural changes in the posterior ramus after posterior lumbar surgery were studied in rabbits. OBJECTIVE: To investigate the structural changes in the posterior ramus after posterior lumbar surgery that may cause injury to the posterior ramus after the procedure. SUMMARY OF BACKGROUND DATA: Investigators in previous studies have pointed out that low back discomfort after lumbar discectomy relates to neurogenic changes and/or myogenic changes of paravertebral muscle. However, no previous study has demonstrated the effects of excessive nerve root retraction on spinal posterior rami. METHODS: Eighteen male Japanese White rabbits were used. The posterior ramus arising from the S1 nerve root was examined after exposure of the lamina only, fenestration, or retraction of the S1 nerve root, with light microscopy and transmission electron microscopy at 2, 4, and 6 weeks after the procedure. Results were compared with a those in control specimens that did not undergo the procedure. RESULTS: In the exposed group, no distinct difference was found compared with the control specimen. In the fenestration group, especially at 6 weeks, some attenuation and splitting of myelin sheaths was observed. In the retraction group, the structural alteration was most severe. Even at 2 weeks, fragmentation of many myelin sheaths was detected. Examination of specimens by electron microscopy indicated phagocytosis of myelinated fibers at 4 and 6 weeks. CONCLUSIONS: Findings showed that posterior lumbar procedures, including retraction of paravertebral muscle, fenestration of the lamina, and retraction of the nerve root affect the posterior ramus. Excessive retraction of the nerve root has an especially disastrous effect on the posterior ramus. Such a violent maneuver within the spinal canal must be avoided. 相似文献
54.
Ohashi H Hirohashi K Yamano Y 《The Journal of bone and joint surgery. British volume》2000,82(4):517-525
We have reviewed 103 of 126 Chiari osteotomies carried out in our department between 1956 and 1987. The cases were graded radiologically, using the Japanese Orthopaedic Association (JOA) system, into a pre/early osteoarthritis (OA) group and an advanced OA group. In the pre/early group there were 86 hips. The mean follow-up was for 17.1 years (4 to 37). Preoperatively, 51 hips had an average JOA clinical score of 78.6+/-8.4 points and the final mean JOA clinical score was 89.4+/-12.5 points. Advanced degenerative change developed in 33.7% and one hip required a total replacement arthroplasty (TRA). Chiari osteotomy alone, without accompanying intertrochanteric osteotomy, was performed on 62 hips. For these the median survival time was 26.0+/-2.5 years, using as the endpoint progression to advanced OA. Differences in survivorship curves related significantly to the severity of the preoperative OA, the shape of the femoral head and the level of osteotomy. In the advanced OA group, we followed up 17 hips for a mean of 16.2 years (1 to 27). Before operation, the mean JOA clinical score in 13 hips was 63.2+/-7.9 points and the final score 84.0+/-12.0 points. TRA was eventually carried out on four hips. Our findings suggest that the Chiari osteotomy remains radiologically effective for about 25 years. The procedure is best suited to subluxated hips with round or flat femoral heads and early or no degenerative change. Intra-articular osteotomy can lead to osteonecrosis, and should be avoided. In hips with advanced OA, the Chiari procedure creates an acetabulum which facilitates later TRA, and may delay the need for this procedure in younger patients. 相似文献
55.
Manometric Evidence of Improved Early Gastric Stasis by Erythromycin after Pylorus-preserving Pancreatoduodenectomy 总被引:3,自引:0,他引:3
Matsunaga H Tanaka M Takahata S Ogawa Y Naritomi G Yokohata K Yamaguchi K Chijiiwa K 《World journal of surgery》2000,24(10):1236-1242
Gastric stasis is a frequent complication of pylorus-preserving pancreatoduodenectomy (PPPD). We demonstrated that it might be attributable to delayed recovery of phase III activity of the gastric migrating motor complex due to low concentrations of plasma motilin caused by resection of the duodenum. Leucine 13-motilin is effective for treating gastric stasis, but it is not yet available for clinical use. Whether erythromycin would improve early gastric stasis after PPPD was tested clinically and by manometry. A manometric tube assembly and a gastrostomy tube were inserted in the stomach of 10 patients at PPPD for pressure recording from the gastric antrum and jejunum and for gastric juice drainage, respectively. After baseline recording, erythromycin 5 mg/kg was given intravenously on day 14 and saline as a placebo on day 17 every 4 hours four times a day. The daily volume of gastric juice output and the gastric motility index were measured. The mean period until the return of gastric phase III was 31 +/- 1 days. Erythromycin significantly increased the gastric motility index from 7.9 +/- 1.3 mmHg to 15.7 +/- 1.8 mmHg (p = 0.0005), whereas saline did not (7.2 +/- 1.6 mmHg to 6.5 +/- 1.2 mmHg; p = 0.21). Erythromycin significantly decreased the gastric juice output from 1,080 +/- 190 ml to 738 +/- 199 ml (p < 0.0001), but the saline injections did not (1,064 +/- 174 ml to 1,115 +/- 189 ml; p = 0.35). Erythromycin, a universally available motilin agonist, is a safe, effective, potent drug for the treatment of early gastric stasis after PPPD. 相似文献
56.
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58.
Kuroda S Itoh H Yamagami T Kizu O Murata H Kusuzaki K Yamano T Maeda T 《Skeletal radiology》2000,29(5):293-297
A 41-year-old man presented with an asymptomatic mass in the right medial thigh. Magnetic resonance imaging (MRI) revealed
a well-demarcated, 10-cm mass in the right adductor muscles. The margins of the mass exhibited high signal intensity and the
rest showed low or iso signal intensity on T1-weighted MR images. However, the high signal intensity was decreased on T2-weighted
images with fat suppression. The central part of the tumor was of inhomogeneous high signal intensity on T2-weighted images;
after Gd-DTPA injection it enhanced inhomogeneously on T1-weighted images with fat suppression. On dynamic computed tomography
(CT) in the arterial phase, there were strongly enhancing spotty areas in the tumor. At surgery, a yellow-whitish tumor was
resected and a pathological diagnosis of angiomyolipoma (AML) in the thigh was made.
Received: 21 June 1999 Revision requested: 28 July 1999 Revision received: 13 December 1999 Accepted: 15 December 1999 相似文献
59.
目的 :了解辛伐他汀 (舒降之 )治疗老年人高脂血症的疗效。方法 :对 93例老年高脂血症患者采用舒降之治疗。结果 :治疗了 4周和 8周后 ,胆固醇 (TC)明显降低 2 2 %、2 7% (P <0 .0 1) ,低密度脂蛋白 (LDL C)明显降低 17%、2 4 % (P <0 .0 1) ,高密度脂蛋白 (HDL C)增加 15 %、16 % (P <0 .0 5 ) ,三酰甘油 (TG)降低 18%、2 1% (P <0 .0 5 ) ,仅有轻微不良反应。结论 :辛伐他汀可显著降低TC、LDL C ,可中等程度降低TG及升高HDL C。表明辛伐他汀是治疗老年人高脂血症的理想调脂药物 相似文献
60.
一株抗肿瘤放线菌的筛选及其初步研究 总被引:1,自引:0,他引:1
在经过MTT法初筛得到的具有细胞毒的海洋微生物中 ,我们又采用荧光显微观测法 ,发现放线菌AK 1 1处理的细胞发生凋亡。在琼脂糖电泳上呈现DNA梯度带 ,进一步验证了其具有使细胞凋亡的作用。AK 1 1活性化合物纯品的裸鼠试验结果表明 :其试验浓度为 0 .0 1 6 μg·kg- 1,0 .1mL/次和 0 .0 0 8μg·kg- 1,0 .1mL/次时抑瘤率分别为 5 2 .0 %和 33.6 %。对人胃癌细胞MGC 80 3及人胃肝细胞SMMC772 1的IC50 的测定值略小于阿霉素 ,显示了AK 1 1具有较高的抗肿瘤活性。FCM对细胞周期的分析表明 :经AK 1 1处理后细胞在S期发生阻滞。DNA合成受阻 相似文献