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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   
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We report a case of a diaphragmatic hernia after a heart transplant operation. A 43-year-old woman, who underwent orthotropic heart transplantation for hypertrophic cadiomyopathy two year earlier, presented with vomiting and epigastric pain. A computed tomography scan showed that the stomach and transverse colon were dislocated in the left thoracic cavity. We diagnosed left diaphragmatic hernia incarceration and performed laparoscopic repair of the diaphragmatic hernia. A 12 × 8 cm diaphragmatic defect was found intraoperatively on the ventrolateral aspect of the left diaphragm, and the stomach with volvulus had herniated into the thorax through the defect. The hernia was considered to be iatrogenic. The diaphragmatic defect was large, and the diaphragm was thinning. We closed the defect by mesh repair. Laparoscopic mesh repair of the diaphragmatic hernia could be performed safely and with minimal invasiveness.  相似文献   
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Few studies have demonstrated the optimal usage of common inflammatory markers, alone or in combination, based on the cost-effectiveness. We analyzed the yield and cost of C-reactive protein (CRP), white blood cell count (WBC), erythrocyte sedimentation rate (ESR), sialic acid, and protein fractionation in 177 new primary care outpatients with inflammation-related symptoms. A useful result (UR) was assigned if tests contributed to a change in physician's diagnosis or decision-making. Costs of testing were calculated based on either single or simultaneous measurement. Five inflammatory markers generated 147 URs in 123 patients. CRP showed the best contribution to generation of UR, followed by sialic acid, protein fractionation, WBC, and ESR. CRP demonstrated poor correlation with WBC (r = 0.458), while sialic acid strongly correlated with total absolute amount of alpha1 and alpha2 fractions in protein fractionation (r = 0.855) and moderately with ESR (r = 0.651). The combination of CRP and WBC produced the best cost-effectiveness at a cost of Yen 1169 (US dollars 9.6 or Euro 9.7)/additional UR against CRP testing alone. Sialic acid, an automated multichannel analyzer-based test, demonstrated the favorable cost-effectiveness over ESR or protein fractionation when combined with CRP (and WBC). Our results indicate that the optimal usage of these inflammatory markers should involve careful cost-effectiveness considerations.  相似文献   
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We evaluated whether we could predict the neurologic outcome in 55 out-of-hospital cardiac arrest patients using auditory brainstem responses (ABR). ABR patterns were classified into one of 3 types by evaluation of 5 components: type 1, with all 5 components; type 2, lack of at least one response between the 2nd and 5th components; type 3, with only the first component or no response. The relation between the ABR patterns on the 3rd day following resuscitation and the neurologic outcome on hospital discharge was evaluated. The specificity that the 5 awake patients had type-1 ABR was 38%. The sensitivity that the 10 brain dead patients had type-3 ABR was 60%. In the type-1 ABR patients, the negative predictive value that the patients were awake was 100%. In the type-3 ABR patients, the negative predictive value that the patients became brain dead was 90.9%. These results suggest that ABR on the 3rd post-resuscitation day may not be useful for predicting if patients are awake or become brain dead, although the loss of components may be a sign of morbidity, and the presence of the 2nd or later components indicates possible future prevention of brain death.  相似文献   
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A combination of Photo Radiation Therapy (PRT) using Argon-Dye Laser with hematoporphyrin derivatives (HpD) was used experimentally on a cytogenetically highly malignant neuroblastoma xenograft, which exhibited a homogeneously staining region and caused DNA amplifications in chromosomes. The tumor tissue was treated with 500 joules/cm2 of laser. The dosage of HpD was 50 mg per kg body weight. Necrosis of over 50% of the tumor was observed in half the specimens. Swollen cytoplasmic organelles and ruptured cell and nuclear membranes were observed by electron microscopy after PRT. PRT may be used with other treatment modalities for the removal of residual and metastatic tumors.  相似文献   
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Immunosuppressive activities of the newly discovered FK506, isolated from Streptomyces tsukubaensis, were examined by using cardiac allotransplantation in the rat, and the mechanisms underlying induction and maintenance of FK506-induced long-term allograft survival were studied. Male rats of WKA (RT1k) and F344 (RT1lvl) strains were used as recipients and donors, respectively, and those of BN (RT1n) strain were used as third-party donors. Treatment with FK506, beginning from the day of allografting for 14, 10, or as few as 4 days, prolonged allograft survival significantly across the major histocompatibility barrier. The minimum doses for prolonging graft survival were 0.1 mg/kg/day by intramuscular treatment and 1.0 mg/kg/day by oral treatment. Treatment with FK506 at a dose of 0.32 mg/kg/day from day 4 until day 10 resulted in all the grafts surviving indefinitely and from days 5 to 10, half the grafts survived indefinitely, suggesting that the agent inhibited ongoing rejection. On the other hand, cyclosporine treatment at a dose of 20 mg/kg/day from day 2 did not prolong graft survival time statistically significantly. Induction of prolonged graft survival was not obtained by pretreatment of the prospective donor or recipient; prolonging effects were observed only when the agent was administered after allografting. Thus, the primary effect of the agent is exerted on responder lymphocytes reacting to the donor antigens in the induction phase of long-term graft acceptance. The mechanisms underlying the maintenance of long-term grafts were analyzed by testing the capacity of lymphocytes or serum of long-term graft-bearing rats to inhibit graft rejection in irradiated grafted hosts. Transfer of 2 x 10(8) lymphocytes from FK506-induced long-term F344 graft-bearing WKA rats resulted in indefinite survival of F344 heart allografts, but it did not prolong survival of third-party BN hearts. Transfer of 2.5 ml serum from long-term graft-bearing rats also prolonged graft survival of F344 hearts, but not BN hearts. These results suggest that donor strain-specific suppressor cells and humoral factor(s) are induced by treatment with FK506 in the presence of allografts, and that they play at least partial roles in the maintenance of long-term allograft acceptance.  相似文献   
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