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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.
5-Fluorouracil (5-FU) in combination with leucovorin (LV) is nowadays the standard treatment in colon cancer and would be a candidate to be delivered orally to the colon. Eudragit P-4135F or Eudragit RS100 were used separately to prepare microspheres by an oil/oil emulsification process trapping 5-FU and LV simultaneously. Scanning electron microscopy permitted a structural analysis, process parameters were analyzed and drug loading and release profiles were recorded. Particle size varied between 123 (RS100) and 146 microm (P-4135F). Generally, higher encapsulation rates were found with RS100 (5-FU, 60.3+/-9.7%; LV, 81.4+/-8.6%) compared to P-4135F (5-FU, 48.3+/-2.0%; LV, 55.4+/-2.7%). Microparticles made from Eudragit RS100 released the incorporated drug combination within 8 h not exhibiting general differences between the kinetics of both drugs. P-4135F was found to maintain the undesired 5-FU release at pH 6.8 lower than 25% within 4 h while at pH 7.4, a nearly immediate release (within 15 min) was observed. Although the release was similar at pH 7.4, at pH 6.8 LV showed a distinct initial drug loss of about 60% and a complete release within 2 h. SEM analyses revealed a substantial presence of LV crystals on the particle surface provoking a distinct burst effect of LV. These observations were concluded to be related to the high lipophilicity of P-4135F provoking a separation between P-4135F and LV during the preparation process.  相似文献   
4.
Scorpion venoms are composed of a number of neurotoxic peptides. A variety of toxins have been isolated from the venoms of scorpions of the family Buthidae, however, little interest has been paid to non-Buthidae scorpions. In this study, we examined the toxicity of the venom of Liocheles australasiae (Hemiscorpiidae) to mice and crickets, and characterized the peptide components by HPLC and mass spectrometry. Over 200 components were detected in the L. australasiae venom by LC/MS analysis, with components of molecular masses ranging from 500 to 5000 Da being particularly abundant. A number of peptides contained two to four disulfide bridges, which was estimated based on the mass difference after derivatization of Cys residues. A peptide having a monoisotopic molecular mass of 7781.6 Da and four disulfide bridges was isolated from the venom. The peptide has a primary structure similar in terms of the position of eight Cys residues to those observed in several peptides found from scorpions, ticks and insects, although biological roles of these peptides are unknown.  相似文献   
5.
A 33-year-old man with a left testicular tumor was referred to Shinshu University Hospital for advanced therapy. Radiographic imaging revealed multiple metastases in the retroperitoneal lymph nodes (RPLN) and bilateral lungs, as well as tumor thrombus that extended from the left renal vein to the inferior vena cava (IVC) adjacent to the right atrium. After orchidectomy, a diagnosis of embryonal carcinoma was made with a clinical stage of T1N2M1bS3, which has a poor prognosis, based on the International Germ Cell Cancer Collaborative Group consensus. After eight courses of chemotherapy, the patient's tumor markers normalized and the lung metastases disappeared, but the RPLN and tumor thrombus remained. Retroperitoneal lymph node dissection and thrombectomy were performed using a veno-venous bypass (VVB). The pathological examination of the thrombus revealed a mature teratoma. The patient has been disease-free since surgery.  相似文献   
6.
Solitary fibrous tumors (SFT) have recently been established to be of mesenchymal origin. Although there are numerous reports of SFTs arising from the pleura, reports of the tumor arising from extrapleural sites are comparatively rare [Fletcher CDM, Unni K, Mertens F (eds) World Health Organization classification of tumors, pathology & genetics, tumors of soft tissue and bone. IARC Press, Lyon, pp 86–901, 2002]. We report a case of SFT arising in the inguinal region.  相似文献   
7.
We report a case of Gianotti-Crosti syndrome associated with human herpesvirus-6 (HHV-6) infection. An eight-month-old girl developed monomorphous papules on her cheeks, buttocks, and extremities after the subsidence of exanthema subitum. Viral antibody analysis confirmed primary HHV-6 infection. HHV-6 may be added to the list of causative agents of Gianotti-Crosti syndrome.  相似文献   
8.
The effect of (+)-5-oxo-D-prolinepiperidinamide monohydrate (NS-105), a novel cognition enhancer, on adenylate cyclase activity was investigated in cultured neurons of the mouse cerebral cortex. NS-105 (10–7 and 10–6 M) inhibited forskolin-stimulated cyclic AMP formation, an action that was dependent on pertussis toxin-sensitive G proteins. Conversely, in pertussis toxin-pretreated neurons, NS-105 (10–7 –10–5 M) significantly enhanced the forskolin-stimulated cyclic AMP formation, and this action was completely reversed by cholera toxin. A metabotropic glutamate receptor agonist (1S, 3R)-1-aminocyclopentane-1, 3-dicarboxylic acid (1S, 3R-ACPD) produced similar bi-directional actions on the cyclic AMP formation. Both of these inhibitory and facilitatory actions of NS-105 and 1S, 3R-ACPD were blocked by L(+)-2-amino-3-phosphopropinoic acid (L-AP3). NS-105 (10–6 M) and 1S, 3R-ACPD (10–4 M) significantly enhanced isoproterenol- and adenosine-stimulated cyclic AMP formation. The enhancement of such Gs-coupled receptor agonists-stimulated cyclic AMP formation was also produced by quisqualate but not by L(+)-2-amino-4-phosphonobutanoate (L-AP4). The phosphoinositides hydrolysis was enhanced by 1S, 3R-ACPD (10–4 M) but not by NS-105 (10–6 M), however, 1S, 3R-ACPD-induced increase in phosphoinositides turnover was attenuated by NS-105. These findings suggest that NS-105 stimulates metabotropic glutamate receptor subclasses that are coupled both negatively and positively to adenylate cyclase, but it acts as an antagonist at the receptor subclasses that are linked to phosphoinositides hydrolysis. Received: 3 February 1997 / Accepted: 25 April 1997  相似文献   
9.
Abstract: Light microscopic observations on the superficial pineal gland of Wistar-King rats were made to examine whether or not pineal volume and pinealocyte size, expressed as nuclear density, at daytime or nighttime are affected by long-term exposure to 50 Hz rotating magnetic field (MF) at 5.0 μT. Determinations of pineal volume and pinealocyte size were repeated twice (April and October) during the year. Size of pinealocytes in MF-exposed and sham-exposed rats exhibited, in addition to the difference between peripheral and central regions, regional differences in a proximodistal direction; pinealocytes in the distal and middle-peripheral regions were usually larger than those in the proximal and middle-central regions at daytime or nighttime. In October, distal and proximal pinealocytes showed significant day-night changes in size in sham-exposed rats, but not in MF-exposed animals. The situations in the two groups were almost reversed in April. Significant day-night differences were scarcely found in pinealocyte size in the middle region in the two groups. Throughout the study, pineal volume and pinealocyte size in each region were generally the same between MF-exposed and sham-exposed rats at daytime or nighttime. The results suggest that pinealocytes in the distal and proximal regions, but not those in the middle region, are affected by MF-exposure; day-night differences in sizes of distal and proximal pinealocytes appear in April and disappear in October under the influence of MF. MF may exert an effect on mechanisms controlling day-night rhythms of pinealocyte size in the rat.  相似文献   
10.
Multifactorial analysis on 395 patients revealed important factors which prolong the pyuria after transurethral prostatectomy. They were the age of the patient, anemia and leukocytosis before surgery. These are factors which relate with the defense mechanism of the patient. Local factors, such as the duration of indwelling urethral catheter, the size of the prostate or prostatic bed and preoperative infection, were not so important for prolonging the pyuria after transurethral prostatectomy. The time of the resection and weight of the prostate had an intimate relation each other, and the former was the more important factor. The use of antimicrobials probably controlled these local risk factors, thus making them unimportant in the prolongation of the pyuria after transurethral prostatectomy.  相似文献   
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