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1.

Purpose

Suppression of respiratory movement of the liver would be desirable for high-precision radiation therapy for liver tumors. We aimed to investigate the effect of our original device-free compressed shell fixation method and breathing instruction on suppression of respiratory movement. The characteristics of liver motion based on the movement of a fiducial marker were also analyzed.

Methods and Materials

First, respiratory amplitudes of the liver with the device-free compressed shell were analyzed from the data of 146 patients. The effect of this shell fixing method on liver movement was evaluated. Second, as another cohort study with 166 patients, interfractional internal motion of the liver for patients fixed in the shell was calculated using the fiducial marker coordinate data of images for position setting before daily irradiation. Third, in another 12 patients, intrafractional internal motion was calculated from the fiducial marker coordinate data using x-ray images before and after irradiation.

Results

The median respiratory movement without the shell, after fixing with the shell, and after instructing on the breathing method with the shell was 14.2 (interquartile range, 10.7-19.8), 11.5 (8.6-17.5), and 10.4 mm (7.3-15.8), respectively. Systematic and random errors of interfractional internal motion were all ≤2 mm in the left-right and anteroposterior directions and 3.7 and 3.0 mm, respectively, in the craniocaudal direction. Systematic and random errors of intrafractional internal motion were all ≤1.3 mm in the left-right and anteroposterior directions and 0.8 and 2.4 mm, respectively, in the craniocaudal direction.

Conclusions

The device-free compressed shell fixation method was effective in suppressing the respiratory movement of the liver. Irradiation position matching using the fiducial marker can correct the interfractional internal motion on each day, which would contribute to the reduction of the margin to be given around the target.  相似文献   
2.

Background

On April 1, 2016, the Ministerial ordinance was enforced, and musculoskeletal examination of the extremities was made mandatory. From 2008, the University of us started musculoskeletal direct examination. To expand the examination, from 2016, we started to use the marksheet-type questionnaire. This study aimed to report the results of a musculoskeletal examination and investigate the association between musculoskeletal examination and age/gender and reports the reliability of the collected questionnaire data.

Methods

Direct musculoskeletal examination was performed in K school by 7 orthopedic surgeons. A marksheet-type screening questionnaire was distributed to all the elementary and junior high school students in Tsukuba and Hitachiomiya cities. The rates of abnormal findings for scoliosis, standing flexion, full squatting with the heels on the floor, general joint laxity, and standing on one leg, torticollis, and flat feet were calculated. We compared the results of the questionnaire and direct examination and calculated sensitivity, specificity, and odds ratio.

Results

A total of 1844 students in K school had direct examination, and 22,494 questionnaires were able to correct in Tsukuba and Hitachiomiya cities. The rates of abnormal findings in direct examination/questionnaire in scoliosis, standing flexion, full squat, general joint laxity, standing on one leg, torticollis and flat foot were 18.7% (344/1842)/5.1% (1094/21441), 20.2% (372/1841)/26.6% (5817/22078), 6.2% (114/1832)/6.9% (1516/22101), 7.5% (1648/22252), 4.9% (1100/22077), 2.2% (31/1844)/1.2% (272/21687), and 12.5% (231/1842)/8.7% (1785/20871), respectively. Sensitivities of the questionnaire for scoliosis, stand flexion, full squatting, torticollis, and flat feet were 16.8% (53/316), 67.9% (250/368), 48.2% (55/114), 18.9% (7/37), and 32.2% (65/202), respectively.

Conclusion

We reported the result of musculoskeletal examination. Accuracy and reliability of this questionnaire were not satisfactory. To perform high quality musculoskeletal examinations, we will aim to increase the quality of screening methods.  相似文献   
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5.
The fit and fill of the femoral canal are critical to the success of cementless femoral stems in total hip arthroplasty. It is difficult for conventional stems to provide a good fit and fill for the femora of patients with secondary osteoarthritis. Based on measurements of 100 femora of these patients, we designed two types of Fukui Medical School (FMS) stems with a proximal lateral flare that differed in the medial radius. We compared the fit and fill of the FMS stems with those of four conventional stems, using computer simulation. The mean proximal fit and total fit of the FMS stems were 46% and 53% respectively, a significant improvement compared with the other stems examined. The mean fill of FMS stems was 82% at the lower end of the lesser trochanter and 84% at the upper end of the isthmus, values that were significantly higher than those of the other stems. Since September 1995, we have implanted FMS stems in 15 hips with secondary osteoarthritis. Radiographic evaluations showed that the canal fill of the FMS stems was significantly greater in the proximal femur compared with other stems previously inserted at our department. A summary of this paper was presented at the 9th Symposium on Computer-Assisted Radiology; June 1995, Berlin, and at the 8th International Symposium on Technology in Arthroplasty; September 1995, Puerto Rico.  相似文献   
6.
Multicentricity of hepatocellular carcinoma (HCC) is considered, especially in patients with liver cirrhosis. This paper describes an operative case of a male patient with probable multicentric development of HCC in precirrhotic fibrosis. The main tumors inside the capsule were completely necrotic due to transarterial embolization (TAE). Histologic examination disclosed discrete tiny nodules of HCC that were not detected grossly. They showed highly differentiated trabecular arrangements: Edmondson I. A scirrhous type was noted in the center of the tumors. At the borders of the tumors the carcinoma cells exhibited replacing growth patterns and it was thought that they developed multicentrically. Partial resection must be performed as extensively as possible in a case such as the present one.  相似文献   
7.
8.
Definition of carcinoma of the gastric cardia   总被引:8,自引:0,他引:8  
Summary This study concerns the definition of carcinoma of the gastric cardia. The topography of the esophagogastric mucosal junction (mucosal EGJ) was investigated with an endoscope in 182 patients who were free of hiatal hernias, ulcers, and neoplasms in the esophagus and stomach. The relationship between the EGJ and the cardiac gland area was then examined histologically in 56 resected specimens containing intact EGJs and cardia gland areas. Furthermore the cancerous center was determined; the shortest distance between the cancerous center and the EGJ and the amount of esophageal invasion were measured in 102 resected carcinomas located close to the junction; the carcinomas contained the EGJ and were good enough for pathohistological examination. The EGJ was located 0.5–1.0 cm proximal to the His angle (the gastric cardia) in radiological and endoscopic examinations. Histologically the cardiac gland area was found to straddle the EGJ at a range of about 1 cm proximal and 2 cm distal to the junction. Among the upper stomach carcinomas, most of the tumors (87.5%) whose center was located within 2 cm from the EGJ invaded the esophagus. In conclusion, carcinoma of the gastric cardia is defined as a lesion with its center located within 1 cm proximal and 2 cm distal to the EGJ.
Definition des Kardiacarcinoms
Zusammenfassung Diese Untersuchung befaßt sich mit der Definition von Carcinomen der Kardia. An 182 Patienten, die weder Hiatushernien, Ulcera noch Neoplasien des Oesophagus bzw. des Magens aufwiesen, wurde die Lage des Übergangs von der Oesophagus- zur Magenmucosa (esophagogastric mucosal junction, EGJ) endoskopisch untersucht. Dann wurde die Beziehung zwischen EGJ und dem Drüsengebiet der Kardia histologisch anhand von 56 Resektaten mit intaktem EGJ und Kardiadrüsenzone untersucht. Außerdem wurde an 102 resezierten Carcinomen mit Sitz in der Nähe des gastrooesophagealen Übergangs die kürzeste Ent fernung zwischen Carcinomzentrum und EGJ und das Ausmaß der Oesophagusinfiltration bestimmt; die Proben schlossen den EGJ ein und konnten pathohistologisch beurteilt werden. Bei der radiologischen und endoskopischen Untersuchung fand sind der EGJ 0,5–1,0 cm vom His-Winkel entfernt. Die histologische Untersuchung zeigte, daß die Kardiadrüsenzone sich vom EGJ etwa 1 cm nach proximal und 2 cm nach distal erstreckt. Die meisten Tumoren des oberen Magens (87,5%), deren Zentrum innerhalb von 2 cm vom EGJ entfernt lag, infiltrierten in den Oesophagus. Ein Kardiacarcinom ist demzufolge als Läsion zu definieren, deren Zentrum innerhalb von 1 cm proximal und 2 cm distal des EGJ liegt.
  相似文献   
9.
The role of intracellular Zn2+ in the translocation of protein kinase C from cytosol to membrane fractions was examined by the [3H]phorbol 12,13-dibutyrate (PDBu) binding method in guinea pig cerebral synaptoneurosomes. N-methyl-d-aspartate (NMDA, 100 μM) and calcium ionophore A23187 (0.3–30 μM) decreased the binding activity in the cytosol with a concomitant increase in the membrane fractions. Pretreatment of synaptoneurosomes with a heavy metal chelator, N,N,N′,N′-tetrakis-(2-pyridylmethyl)ethylenediamine (TPEN), inhibited the NMDA- and A23187-induced changes of the distribution of [3H]PDBu binding sites in cytosol and membrane fractions. The inhibitory effect of TPEN was negated by a preincubation of TPEN with equimolar Zn2+ but not by that with Ca2+. The addition of 500 μM Zn2+ to the lysate of synaptoneurosomes induced an increase of [3H]PDBu binding activity in the membrane fraction with a concomitant decrease in the cytosol fraction, as did 100 μM Ca2+. Low concentrations of Zn2+ (10 μM), which alone had no effect on the distribution of the binding, significantly enhanced the effect of 10 μM Ca2+ in the lysate. Under those conditions TPEN inhibited the Zn2+-potentiated Ca2+-dependent changes in the binding. These results suggest that intracellular Zn2+ is essential for the agonist-induced translocation of protein kinase C in guinea pig synaptoneurosomes.  相似文献   
10.
O Koide  S Iwai  K Baba  H Iri 《Cancer》1987,60(6):1325-1330
The identification of atypical testicular germ cells is often difficult by by routine histologic examination. By immunohistochemical detection of placental alkaline phosphatase (PLAP) and by periodic acid Schiff staining of glycogen, atypical germ cells were easily identified in testicular samples. Forty-one fetal and adult testes were used for a preliminary study, and 121 testes from infants and adults with either cryptorchidism or germ cell tumors were studied for the presence of atypical germ cells. Two types of clear germ cells were differentiated histochemically, and one with PLAP-positive cell surfaces and glycogen-rich cytoplasm was considered to be atypical. The alkaline phosphatase of atypical germ cells appeared to be similar to that found in a few germ cells of early fetal testes. The atypical germ cells seemed to be multi-potential malignant cells capable of developing not only into seminoma but also into other germ cell tumors. Only in yolk sac tumor of infants were the atypical germ cells absent from tumor-adjacent seminiferous tubules.  相似文献   
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