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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.
3.
There have been no systematic efforts to manage and treat patients with frontotemporal dementia (FTD), but Perry described pharmacologic interventions for some behavioral syndromes in 2001. In Perry's report, selective serotonin reuptake inhibitors (SSRI) were recommended as first choice drugs because they were well tolerated and might have an effect on some symptoms such as compulsive symptoms and eating abnormalities. Some reports were presented concerning Japanese FTD patients which showed the effect of SSRI on stereotyped behaviors and eating abnormalities by Nishikawa, et al. (2001), Ikeda, et al. (2004), and others. We describe two FTD patients with compulsive complaints of pain, one mainly on abdomen and the other on lumbar region. Fluvoxamine markedly improved their complaints of pain as well as stereotyped symptoms. Fluvoxamine might be effective for behavioral disturbances due to improvement of serotoninergic dysfunction in frontal medial and cingulated cortices, as previously described. Moreover, it has been reported that an altered response to pain stimuli, either via a loss of awareness of pain or exaggerated reaction to pain, is a specific feature of FTD, but there have been only a few reports on this feature. Fluvoxamine might be effective for compulsive complaints of pain due to improvements of compulsive symptoms and exaggerated reactions to pain in FTD, or due to the analgesic effect of SSRI. SSRI may improve compulsive complaints of pain in FTD patients.  相似文献   
4.
The present study was undertaken to evaluate the role and possible interaction of the endogenous opioid peptide (EOP) and corticotropin-releasing factor (CRF) in the acute stress-induced suppression of gonadotropin secretion in ovariectomized estrogen-primed rats. An intravenous (i.v.) injection of naloxone (10 or 20  mg/kg), an EOP antagonist, significantly elevated serum luteinizing hormone (LH) levels within 10  min in non-stressed animals. The naloxone-induced LH release was completely eliminated when tested 30  min after the onset of acute immobilization. In a subsequent study, it was found that suppression of the naloxone-induced LH release occurred as early as 5  min after the stress onset, and was still evident 60  min after the end of a 30-min period of immobilization. The effect of naloxone was restored 3  h after liberation of the animal from the 30-min immobilization. An intraventricular (i.c.v.) injection of CRF (1 or 5  μg) also significantly suppressed, in a dose-related manner, the effect of a subsequent i.v. injection of naloxone. However, an i.c.v. injection of α -helical CRF(9-41) (25 or 50  μg), a CRF antagonist, prior to immobilization, could not interfere with the suppressive effect of stress on naloxone-induced LH release. These results suggest that both acute immobilization stress and CRF can inhibit the LH secretory activity without mediation by EOP neurons. However, the stress-related suppression may involve non-CRF mechanism(s).  相似文献   
5.
The Carpentier-Edwards pericardial bioprosthesis has been markedly improved in the long-term results and valve-related complications including valve dysfunction, compared to the previous generation bioprosthesis. We report a patient in whom transient prosthetic valve regurgitation and hemolysis occurred early after mitral valve replacement using a Carpentier-Edwards pericardial bioprosthesis and were resolved by preservative therapy. The patient was a 77-year-old female diagnosed with severe mitral valve stenosis and insufficiency. She underwent mitral valve replacement with a Carpentier-Edwards pericardial bioprosthesis. Opening and closing of the three leaflets looked good on intraoperative transesophageal echocardiography (TEE). The only prosthetic valve regurgitation was evident at the central region where the leaflets form coaptation, and no abnormal findings were seen. Serum lactate dehydrogenase (LDH) was decreased to 405 U/l after surgery. However, LDH again began to increase on the 3rd day after surgery and it increased to 1,830 U/l on the 14th day after surgery. Hemolytic urine was detected on 10th day after surgery. PVL was not detected, but moderate abnormal regurgitation from the outside of the stent pocket was detected on TEE. Revision of valve replacement was considered, but LDH thereafter to 393 U/l on 41st day after surgery. The TEE was repeated, and only a trace of central jet was detected without abnormal regurgitation, unlike the previous examination. The patient did not develop any complications thereafter and was discharged on 47th day after surgery. LDH was nearly normal at the time of discharge.  相似文献   
6.
As a prospective study on asymptomatic microhematuria, complete urological examinations including cystoscopy, IVP, ultrasound and urinary cytology were performed on 422 patients over 40 years old between January 1987 and December 1988 (group A). The results of group A was compared with that of retrospective study on 266 patients, who had incomplete urological examination between January 1984 and December 1985 (group B). Cystoscopy was performed on 321 patients (87.2%) in group A and on 108 patients (40.6%) in group B. Bladder tumor was found in 10 cases (2.4%) in group A, including 7 cases of male patients (5.7%), but in only 1 case (0.4%) in group B. Since the negative rate of abnormal urinary cytology was 50% and that of abnormal IVP was 90% in 10 cases of bladder tumor in group A, cystoscopy was considered to be an essential examination for the screening of patients with asymptomatic microhematuria over 40 years old patients.  相似文献   
7.
Using immunoaffinity chromatography, two species of apo-AI containing lipoproteins (AILp); lipoprotein containing apo-AI and apo-AII (Lp-AI/AII), and lipoprotein containing apo-AI, but no apo-AII (Lp-AI) were isolated from 13 female patients on continuous ambulatory peritoneal dialysis (CAPD), then characterized. The results were compared with findings obtained in agematched normolipidemic (control I) and mild hypertriglyceridemic (control II) female subjects. In comparison with control I: In AILp, the levels of total cholesterol (TC), cholesteryl ester (CE) and phospholipid (PL), and the levels of apoE were significantly lower in the CAPD patients while the levels of triglyceride (TG) and apo-CIII were significantly higher in these patients. The levels of apo-AI and apo-AII did not differ between the CAPD and control subjects. In Lp-AI/AII, changes of TC, CE, PL, TG, and apolipoproteins were similar to those of AILp, except for the ratio of apo-AI/apo-AII and the level of apo-CII, which was higher in the CAPD patients. In Lp-AI, changes of TC, CE, PL, and TG were also similar to those of AILp and Lp-AI/AII, but the apo-AI level was significantly lower in the CAPD patients. In comparison with control II: In AILp, the levels of PL, apo-AI, apo-AII, and apo-E were significantly lower in CAPD patients, but the apo-CIII levels were significantly higher. In Lp-AI/AII, the levels of PL and apo-E were significantly lower in CAPD patients.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
8.
The endogenous hallucinogen, N,N-dimethyltryptamine (DMT), was labeled with carbon-11 and its regional distribution in rat brain studied. [11C]DMT showed higher accumulation in the cerebral cortex, caudate putamen, and amygdaloid nuclei. Studies of the subcellular distribution of [11C]DMT revealed the specific localization in the fractions enriched with serotonin receptors only when a very low dose was injected into rats. The proportions of the radioactivity in receptor-rich fractions were greatly enhanced by pretreatment with the monoamine oxidase inhibitor, pargyline. Specific binding of [11C]DMT to serotonin receptors in dog brain was demonstrated by a positron emission tomographic study in which 5-methoxy-N,N-dimethyltryptamine caused approximately 20% displacement of the radioligand from the receptors.  相似文献   
9.
Left ventricular (LV) remodeling after myocardial infarction (MI) is a maladaptive process that increases the risk of heart failure and death. The myocardial phosphoinositide cycle, which is located downstream from several neurohumoral factors, plays a crucial role in LV remodeling. Our animal studies demonstrated that 1-[1-11C]butyryl-2-palmitoyl-rac-glycerol (11C-DAG) can be used to visualize regions with an activated phosphoinositide cycle. Therefore, we examined whether myocardial 11C-DAG accumulation assessed by PET is relevant to LV enlargement and systolic dysfunction in post-MI patients. METHODS: We performed PET with 11C-DAG in 13 post-anteroseptal MI patients and 4 healthy volunteers. We placed regions of interest on the noninfarcted myocardium and calculated the myocardium-to-left atrial (LA) chamber ratio of 11C-DAG accumulation. RESULTS: The myocardium-to-LA chamber ratio of 11C-DAG was significantly higher in the post-MI patients (mean +/- SD, 1.73 +/- 0.35) compared with that of the healthy volunteers (mean +/- SD, 1.25 +/- 0.13; P < 0.05). In the post-MI patients, the myocardium-to-LA chamber ratio of (11)C-DAG was significantly correlated with the LV end-diastolic volume index (r = 0.79, P < 0.01) and the plasma concentration of brain natriuretic peptide (r = 0.85, P < 0.001) and negatively correlated with the LV ejection fraction (r = -0.69, P < 0.01). CONCLUSION: These findings suggest that the myocardial 11C-DAG accumulation assessed by PET is relevant to LV enlargement, LV systolic dysfunction, and humoral activation in post-MI patients. This new imaging strategy based on intracellular signaling may contribute to the assessment and treatment of post-MI patients.  相似文献   
10.
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