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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.
Adolescence is a vulnerable period for developing anxiety-related mental disorders such as post-traumatic stress disorder (PTSD), which requires a long-term course of therapy when a traumatic event has been experienced during childhood. However, the biological mechanism underlying these age-dependent characteristics remains unclear. In the present study, we used early adolescent, late adolescent and adult (4-, 8-, and 15-week old) male mice to examine age differences in fear memory, fear extinction, and spontaneous recovery of fear. We also measured the activation of extracellular signal-regulated kinase (ERK) 2 in the dorsal hippocampus (dHip) and the basolateral amygdala (BLA) following a spontaneous recovery test. Our major findings were as follows: (1) early adolescent and adult mice did not recover the fear response; only late adolescent mice recovered the fear response. (2) The ERK2 in the dHip was more activated after the spontaneous recovery test in late adolescent mice than in adult mice, and the ERK2 in the BLA was more activated after the spontaneous recovery test in adult mice than in late adolescent mice. These results suggest that there exists a unique period in which spontaneous recovery occurs and that these late adolescent behavioral signatures may be related to alteration in the ERK2 phosphorylation in the dHip and BLA.  相似文献   
3.
4.
1. The maximum activity of an antihuman hemolytic amboceptor may be obtained by employing the homologous or heterologous complement, according to the variable relations existing between the species furnishing the amboceptor and the one supplying the complement. Thus, some amboceptors are best reactivated by the complement of the same species, while others may act most strongly when reactivated with the complements of certain suitable heterologous species. 2. From the above it is clear that the complementary activity of a given serum may be very variable according to the varieties of amboceptors employed. In expressing the complementary activity of a serum, the species of the host of the amboceptor must always be stated. Thus, one serum may have many different complementary titers according to the amboceptors used. A similar variation in the titers of the amboceptors occurs when a variety of complements are employed. 3. Certain species of animals (pig and sheep) yield sera which are comparatively poor in reactivating most varieties of antihuman amboceptors. The complements of these species deteriorate rapidly. 4. The serum of chicken contained but little complement for the amboceptors derived from the mammalia, while the amboceptor from the chicken was only poorly, or not at all, reactivable by the complements contained in the mammalian sera. The serum of pig was the only variety which reactivated this amboceptor in a fair degree. 5. For the fixation tests guinea pig complement is the most favorable. This complement is also the most active and durable of those which have been studied. The complements of pig and sheep are quite fixable, but their weakness and rapid deterioration render them unsuitable for fixation purposes. Rabbit complement is quite active but is not easily fixable. Goat complement is, as already stated, difficult to fix, in spite of its strong complementary activity. The other complements are unsuitable because of their feeble complementary activity. 6. For fixation tests the antihuman amboceptors produced in the rabbit and guinea pig are suitable. They are, moreover, very active and do not cause the phenomenon of non-fixation. The amboceptors from other animals are unsuitable, as we cannot find a complement which strongly reactivates them. The amboceptor from the goat is unsuitable because of the danger of masking the fixation phenomenon by subsequent hemolysis. 7. In summing up, we arrive at the conclusion that the rabbit is the best animal for producing antihuman amboceptor, and the guinea pig for supplying complement. The guinea pig produces a good amboceptor, but its small size renders it second in choice. So far, no other animals have been found useful for the fixation experiments.  相似文献   
5.
6.
A left ventricular rupture due to embolic myocardial infarction is extremely rare. A 72-year-old woman developed an acute embolic myocardial infarction and mitral regurgitation due to infective endocarditis. Two days after the infarction, a left ventricular free wall rupture occurred after transesophageal echo examination. She received an epicardial patch and mitral valve replacement. Perioperatively, an intra-aortic balloon pump and long-term antibiotics were used. The postoperative course was uneventful, and she is doing well 10 months after surgery.  相似文献   
7.
BACKGROUND: Although it is clear that dissemination via the blood system involves angiogenesis, it is uncertain whether tumors also induce lymphangiogenesis or simply invade existing peritumoral vessels. The purpose of this study was to elucidate changes in tumor blood and lymph vessels in cases involving the invasion of squamous cell carcinoma in the oral cavity, and its significance. Blood and lymph vessels densities in tongue carcinomas induced in hamsters were investigated. METHODS: Tongue cancer was induced by abrading the right margin of the tongue of each hamster with an endodontic barbed broach and subsequently applying 1.0% 9,10-dimenthl-1,2-benzanthracene (DMBA) dissolved in acetone, three times a week, at the same site. Fresh frozen sections were prepared and blood vessels stained blue by perfusion with Coomassie Brilliant Blue and lymph vessels stained brown for 5'-nucleotidase. The effects on the blood vessels and lymph vessels were observed. RESULTS: The results showed that blood and lymph vessel densities were greater in the advanced carcinoma tissues than in normal tissue. These were compared in terms of the mode of cancer invasion. As tumor invasion progressed, the blood vessel density decreased but lymph vessel density tended to be higher in high-degree tumor invasion than in low-degree tumor invasion. The expression of vascular endothelial growth factor-C was seen more frequently as tumor invasion progressed. CONCLUSIONS: The present findings indicated that angiogenesis and lymphangiogenesis are affected by cancerous invasion.  相似文献   
8.
Pins and wires offer the simplest and most effective tools for managing bone fractures and dislocations. Migration of these devices within the chest is rare, but can cause serious problems. The spontaneous migration of Kirschner wires from the right clavicle to the mediastinum resulted in penetrating injury of the esophagus and pseudo-aneurysm of the brachiocephalic artery in an 84-year-old patient. Two Kirschner wires were removed via a vertical incision on the right shoulder without thoracotomy and the brachiocephalic artery was replaced with a Dacron graft.  相似文献   
9.
We herein report a rare case of portsite metastasis of gallbladder carcinoma which occurred after laparoscopic cholecystectomy. A 64-year-old man underwent laparoscopic cholecystectomy at another hospital for symptomatic cholecystolithiasis. The histological examination revealed an adenocarcinoma of the gallbladder infiltrating the entire wall. Despite the physician's advice the patient refused any additional treatment. Thirteen months after surgery he visited our hospital because of a palpable mass at the scar of the right trocar incision. The nodule was removed and histological examination confirmed metastasis from the gallbladder carcinoma.  相似文献   
10.
Ketogenic capacity of mitochondria from the remnant liver of 70% hepatectomized rats was studied in relation to mitochondrial phosphorylative activity. Ketogenic capacity increased to a maximum of 6.04 +/- 0.39 from 3.84 +/- 0.13 of control, with an enhancement of mitochondrial phosphorylative activity 6 hr after hepatectomy, and then decreased to normal levels within 24 hr. Adenylate energy charge, (ATP + 1/2ADP)/(ATP + ADP + AMP), of the remnant liver decreased to 0.825 +/- 0.006 as compared to 0.849 +/- 0.002 of control 6 hr after operation. At 12 hr, total ketone body concentrations of the arterial blood increased concomitant with a fall in ketone body ratio (acetoacetate/3-hydroxybutyrate) which reflects the decreased liver mitochondrial redox (NAD+/NADH) state. These findings suggest that an enhancement of mitochondrial fatty acid oxidation and ketogenesis occurs concomitant with an enhancement of mitochondrial phosphorylative activity in the remnant liver in response to a decreased energy charge after 70% hepatectomy.  相似文献   
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