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991.
992.
Toshitaka Yoshii Hiroko Ueki Tsuyoshi Kato Shoji Tomizawa Atsushi Okawa 《Skeletal radiology》2014,43(10):1477-1480
Percutaneous vertebroplasty (PVP) has been increasingly performed for the treatment of osteoporotic vertebral compression fracture. Despite its minimally invasive procedure, several complications associated with PVP have been reported, including adjacent-level vertebral fracture. Although rare, recollapse of the same vertebrae after PVP has also been reported. However, previous studies have not described a case in which collapses of both the cemented vertebrae and adjacent-level vertebrae occurred following PVP. Here, we report a rare case of severe kyphotic deformity resulting from collapses at the cemented and adjacent vertebrae after PVP using calcium phosphate cement (CPC). The patient required a highly invasive reconstruction procedure as a salvage surgery. 相似文献
993.
Takahiro Akaishi Naruhiro Ishida Atsushi Shimazaki Hideaki Hara Yasuaki Kuwayama 《Journal of ocular pharmacology and therapeutics》2005,21(6):436-444
AIM: The aim of this study was to examine the effect of a 12-week treatment with two formulations of timolol maleate on the amplitude of the circadian fluctuation in intraocular pressure (IOP). METHODS: Conscious Japanese White rabbits housed under a controlled 12-hour light-dark cycle were used. IOP was measured by a telemetry system. Each animal was treated topically for 12 weeks with 0.5% timolol solution (TM) twice-daily, 0.5% timolol gel-forming solution (TM-gel) once-daily, or saline twice-daily, and the circadian variation in IOP was measured every week. RESULTS: Administration of TM or TM-gel did not change IOP in the light phase, but significantly reduced it in the dark phase in each of the 12 weeks. The IOP reductions at 2 h after administration in the TM and TM-gel groups over the 12 weeks were, respectively, 3.6 +/- 0.3 mmHg and 3.4 +/- 0.2 mmHg versus the Saline group. The amplitudes of the circadian fluctuations in IOP in the TM group in weeks 3, 6, and 12 were 15%, 15%, and 18% smaller than those in the Saline group, while the corresponding values for the TM-gel group were 18%, 16%, and 19%, respectively. CONCLUSIONS: TM-gel administered once-daily was as effective at lowering IOP as TM administrated twice-daily over the 12-week experimental period. This study reveals that, in rabbits, both formulations of the timolol maleate induced significant IOP reductions in the dark phase and decreased the amplitudes of the circadian fluctuations in IOP for 12 successive weeks. 相似文献
994.
Shimoji K Aoki S Nakanishi A Suzuki M Hori M Sato S Hoshito H Kyogoku S Cho N Ozaki Y Suzuki M Kuwatsuru R Sasai K 《Japanese journal of radiology》2012,30(2):116-119
Purpose
The aim of this study was to elucidate the distribution of estimated glomerular filtration rate (eGFR) values in patients who underwent gadolinium-based contrast agent (GBCA)-enhanced magnetic resonance imaging (MRI) at different types of hospitals.Materials and methods
We retrospectively studied 2,550 patients who underwent MRI at five institutions. We recorded the date and value of each patient??s eGFR test. The distribution of eGFR values was compared with that in the general Japanese population.Results
A total of 84.3% of patients had their eGFRs evaluated before GBCA-enhanced MRI. Of these, 84.7% were evaluated within 3?months before the GBCA-enhanced MRI, and 1.3% were evaluated on the day of the GBCA-enhanced MRI. A total of 87.2% of patients tested had an eGFR of ??60?ml/min/1.73?m2; 12.8% had an eGFR of <60 and ??30?ml/min/1.73?m2, and no patients had an eGFR of <30?ml/min/1.73?m2.Conclusion
The rate of renal function evaluation differed among hospitals. The prevalence of low eGFR values was greater in Juntendo Tokyo Koto Geriatric Medical Center than in the other hospitals, and the prevalence of low eGFR values was greater in patients who underwent GBCA-enhanced MRI than in the general Japanese population. 相似文献995.
Katsuhiko Ogasawara Jun Hashimoto Koichi Ogawa Atsushi Kubo Nobutoku Motomura Hyoji Hasegawa Takashi Ichihara 《European journal of nuclear medicine and molecular imaging》1998,25(11):1537-1544
The aim of this study was to obtain quantitative iodine-123 brain single-photon emission tomographic (SPET) images with scatter
and attenuation correction. We used a triple-headed SPET gamma camera system equipped with fan-beam collimators with a technetium-99m
line transmission source placed at one of the focal lines of the fan-beam collimators. Four energy windows were employed for
data acquisition: (a) 126–132 keV, (b) 132–143 keV, (c) 143–175 keV and (d) 175–186 keV. A simultaneous transmission-emission
computed tomography scan (TCT-ECT) was carried out for a brain phantom containing 123I solution. The triple energy window scatter correction was applied to the 123I ECT data measured by means of the windows (b), (c) and (d) acquired by two detectors. Attenuation maps were reconstructed
from 99mTc TCT data measured by means of the windows (a), (b) and (c) acquired by one detector. Chang’s iterative attenuation correction
method using the attenuation maps was applied to the 123I ECT images. In the phantom study cross-calibrated SPET values obtained with the simultaneous mode were almost equal to those
obtained with the sequential mode, and they were close to the true value, within an error range of 5.5%. In the human study
corrected images showed a higher grey-to-white matter count ratio and relatively higher uptake in the cerebellum, basal ganglia
and thalamus than uncorrected images. We conclude that this correction method provides improved quantification and quality
of SPET images and that the method is clinically practical because it requires only a single scan with a 99mTc external source.
Received 6 June and in revised form 27 July 1998 相似文献
996.
Interaction between low dose-rate irradiation, mild hyperthermia and low-dose caffeine in a human lung cancer cell line. 总被引:4,自引:0,他引:4
H Sakurai N Mitsuhashi Y Tamaki T Akimoto O Murata Y Kitamoto K Maebayashi H Ishikawa K Hayakawa H Niibe 《International journal of radiation biology》1999,75(6):739-745
PURPOSE: To investigate cell killing by means of low dose-rate irradiation (LDRI) combined with concurrent mild hyperthermia and to determine the effect of low-dose caffeine on this combination treatment. MATERIALS AND METHODS: Human lung adenocarcinoma cells, LK87, were treated with LDRI (50 cGy/h) in combination with mild hyperthermia at 41 degrees C and low-dose caffeine (1 mM). Cell survival was estimated by clonogenic assay. Flow-cytometry was performed with PI staining using FACScan. Heat-shock protein (HSP72/73) was measured by the Western blotting method. All treatments were simultaneously performed for up to 48 h (24 Gy). RESULTS: LDRI cytotoxicities were enhanced by hyperthermia at 41 degrees C. D0 calculated from the dose-response curve for LDRI combined with 41 degrees C was 3.46 Gy whereas it was 6.55 Gy for LDRI alone. The survival curve for LDRI +41 degrees C demonstrated no chronic thermotolerance up to 48 h. For LDRI + simultaneous low-dose caffeine, cell killing was also enhanced, where D0 was 3.38 Gy at 37 degrees C. Radiosensitization caused by caffeine was enhanced by combination with simultaneous mild hyperthermia at 41 degrees C, where D0=1.78 Gy. Cell cycle analysis demonstrated remarkable G2 and mild G1 arrest for LDRI alone, but only G1 arrest was observed for LDRI combined with 41 degrees C and for LDRI combined with caffeine. Strong and early G1 arrest was observed in the treatment with LDRI + caffeine at 41 degrees C. The amount of HSP72/73 in the combination of LDRI with caffeine at 41 degrees C was less than that at 41 degrees C alone. CONCLUSION: LDRI cytotoxicity was enhanced by non-lethal hyperthermia. Low dose caffeine produced further cell killing in the combination of LDRI with mild hyperthermia. 相似文献
997.
Yasuo Kuwabara Yuichi Ichiya Makoto Otsuka Takashi Tahara Toshimitsu Fukumura Ranjan Gunasekera Atsushi Ichimiya Kouji Masuda 《Annals of nuclear medicine》1990,4(3):75-82
We compared I-123 IMP and 99m-Tc HMPAO SPECT studies with 0-15 H2O and F-18 FDG PET studies, and evaluated the clinical significance of SPECT studies in dementia. Seventeen patients including 9 patients with Alzheimer's disease, 3 patients with Pick's disease and 5 patients with multi-infarct dementia were studied. IMP and HMPAO SPECT studies could not detect mildly affected areas when compared with FDG PET. However, they revealed decreased perfusion in the bilateral parietal regions in Alzheimer's disease and in the bilateral frontal regions in Pick's disease, while MRI and/or CT showed mild to moderate cerebral atrophy. IMP and HMPAO SPECT studies can be easily performed in clinical practice, and these findings were useful in the differential diagnosis of dementia. Our preliminary results suggested that SPECT studies with I-123 IMP and Tc-99m HMPAO, despite their limitations, are useful in the differential diagnosis of dementia. 相似文献
998.
Tohru Hashimoto M.D. Hironobu Nakamura Shinichi Hori Kaname Tomoda Katsuyuki Nakanishi Takamichi Murakami Takahiro Kozuka Morito Monden Mitsukazu Gotoh Chikazumi Kuroda Kenichi Wakasa Masami Sakurai 《Cardiovascular and interventional radiology》1995,18(2):82-86
Purpose: To evaluate the efficacy of transcatheter oily chemoembolization (TOCE) for hepatoceliular carcinoma (HCC) on the basis
of microscopic and macroscopic findings postembolization.
Methods: HCCs ranging in size from 0.5 to 13 cm (mean 3.6 cm) were obtained from partial hepatectomies of 100 consecutive patients
who had undergone TOCE between 20 and 246 days (mean 59.5 days) prior to surgery. The efficacy of TOCE was assessed on the
basis of the necrotic to live cell ratio of the tumors. The microscopic pattern of tumor growth was grouped into expanding
type (complete capsule formation) and replacing type (incomplete or no capsule). There were five types of macroscopic groupings:
single nodule, single nodule with extranodular growth (SNE), contiguous and noncontiguous multinodular, and massive growth
type.
Results: Among 79 cases with the expanding type, 29 (37%) had 100% HCC necrosis, but none with 100% necrosis were in the replacing
type. By macroscopic grouping, the efficacy of TOCE decreased from the single nodule type (50% of patients had 100% necrosis)
to the SNE type (21%), and the other types (9%). 相似文献
999.
Immunohistological evaluation of single small hepatocellular carcinoma with negative staining of monoclonal antibody Hepatocyte Paraffin 1 总被引:1,自引:0,他引:1
BACKGROUND AND OBJECTIVES: The sensitivity and specificity of the monoclonal antibody Hepatocyte Paraffin 1 (Hep Par 1) for hepatocellular carcinoma (HCC) are very high, and the usefulness for differential diagnosis of hepatic tumors has been reported. However, there are some cases of HCC with negative staining for Hep Par 1. We examined the histopathological features of HCC with negative staining for Hep Par 1. METHODS: We examined 69 samples of single nodular HCC less than 2 cm in greatest dimension, resected from 1985 to 1994 in our hospital, with immunohistological staining for Hep Par 1, cytokeratin 19 (CK 19), MUC-1 glycoprotein (MUC-1), and epithelial membrane antigen (EMA). RESULTS: Hep Par 1 staining was positive in 64 cases (93%) and negative in 5 cases (7%). With regard to the histological structure, 3 of the 5 negative cases were scirrhous HCC. With regard to the grade of histological differentiation, 2 cases were poorly differentiated HCC, 3 cases were moderately differentiated HCC, and no well-differentiated HCC was found in the negative cases. CK 19, MUC-1, and EMA staining were negative in all cases. CONCLUSIONS: It is necessary to recognize the existence of Hep Par 1 negative HCC, in particular scirrhous HCC. This may be due to a different mechanism in the earlier stage of hepatocarcinogenesis. 相似文献
1000.
Ohmura Y Matsunaga K Motokawa I Sakurai K Ando T 《Cancer biotherapy & radiopharmaceuticals》2003,18(5):769-780
We investigated the effects of a protein-bound polysaccharide, PSK, on the resistance of tumor-bearing mice against Candida albicans infection. In BALB/c mice that had received subcutaneous (sc) transplantation of fibrosarcoma Meth A, viable fungal counts were increased in the kidney and the mean survival period was shortened after challenge with C. albicans, compared with healthy mice. Oral administration of PSK to such mice resulted in a significant decrease of viable fungal counts and a prolongation of the mean survival period. The ratio of CD4-positive T cells in the spleen was decreased in noninfected tumor-bearing mice and the decrease was prevented by PSK, although in vitro anticandida activities of phagocytes were not significantly affected by tumor burden or PSK. Further, intracellular interferon (IFN)-gamma productivity was enhanced and the number of IFN-gamma-producing CD4-positive T cells was enhanced by PSK. PSK enhanced the gene expression of interleukin (IL)-12 and IFN-gamma in the spleen of tumor-bearing mice inoculated with C. albicans. Treatments with anti-IL-12 or anti-IFN-gamma antibody reduced the anti-infectious effects of PSK. These findings suggest that the protective effect of PSK on sublethal inoculation with C. albicans in tumor-bearing mice is possibly mediated by Th1 cell functions. 相似文献