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21.
Jun Maeda Mitsunori Ohta Hirohisa Hirabayashi Hikaru Matsuda 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(4):196-198
We present a case of lung cancer that showed false positive accumulation in an 18F fluorodeoxyglucose positron emission tomography (FDG-PET) scan following induction chemotherapy for suspected metastasis
and progression of malignancy. A 66-year-old man was diagnosed with squamous cell carcinoma in the lung, classified as clinical
stage IIIA (T2N2M0), and underwent induction chemotherapy. An FDG-PET scan prior to chemotherapy demonstrated accumulation
only in the tumor, whereas following treatment it revealed a strong accumulation not only in the tumor, but also in the supraclavicular
lymph nodes, which indicated lymph node metastasis. The patient underwent a biopsy of the right supraclavicular lymph node
and mediastinoscopy, after which all dissected lymph nodes showed sarcoid reactions and no tumor cells were found pathologically.
We concluded that when evaluating the effect of induction chemotherapy for malignancy, a sarcoid reaction might lead to the
false positive accumulation of FDG. 相似文献
22.
Yasushi Sano Hirohisa Machida Kuang‐I. Fu Hiroaki Ito Takahiro Fujii 《Digestive endoscopy》2004,16(Z1):S93-S96
The goal of endoscopic mucosal resection (EMR) is to allow the endoscopist to obtain tissue or resect lesions not previously amenable to standard biopsy or excisional techniques and to remove malignant lesions without open surgery. In this article, we describe the results of conventional EMR and EMR using an insulation‐tipped (IT) electrosurgical knife (submucosal dissection method) for large colorectal mucosal neoplasms and discuss the problems and future prospects of these procedures. At present, conventional EMR is much more feasible than EMR using IT‐knife from the perspectives of time, money, complication, and organ preservation. However, larger lesions tend to be resected in a piecemeal fashion; and it is difficult to confirm whether EMR has been complete. For accurate histopathological assessment of the resected specimen en bloc EMR is desirable although further experience is needed to establish its safety and efficacy. Further improvements of in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms. 相似文献
23.
T. Mizutani S. Sakamaki N. Tsuchiya S. Kamei H. Kohzu R. Horiuchi M. Ida R. Shiozawa T. Takasu 《Acta neuropathologica》1992,84(4):372-377
Summary We describe two patients with sporadic amyotrophic lateral sclerosis (ALS), who had developed progressive external ophthalmoplegia of a predominantly supranuclear type while they survived on respirators, and displayed histopathological abnormalities both typical and atypical of ALS. Patient 1 was a 43-year-old man with ALS of 5-year duration, who had initially exhibited fulminant ALS, and remained on a respirator for 4 years. Patient 2 was a 51-year-old man with ALS of 13-year duration, who remained on a respirator for 8 years. Both patients died in a totally locked-in state. Autopsy of both patients revealed not only histopathological abnormalities consistent with ALS, but also multisystem degeneration which involved the pontine tegmentum, substantia nigra, Clarke's dorsal nuclei and spinocerebellar tracts. In addition, Patient 2 displayed intracyto-plasmic neuronal basophilic inclusion bodies which exhibited marked immunoreactivity to anti-ubiquitin antibodies. Our case reports indicate that the longer survival which is possible through the use of respirators may make one subgroup of ALS patients prone to develop atypical clinical and neuropathological features which are not observed during the natural cours of ALS.Supported by a Grant-in-Aid from the Research Committee of CNS Degenerative Diseases, the Ministry of Health and Welfare of Japan, and by a Grant from Nihon University School of Medicine, Tokyo 相似文献
24.
Hirohisa Miyake Patrick O. Eghwrudjakpor Takashi Sakamoto Koreaki Mori 《Child's nervous system》1992,8(5):243-246
Experimental hydrocephalus was induced in rats by intracisternal injection of kaolin suspension. The amounts of norepinephrine and dopamine were determined in the whole brain and specific brain regions at 1 week (acute phase) and 4 weeks (chronic phase). The turnover of catecholamine, an index of the activity of catecholamine-containing neurons, was determined by measuring the decrease in catechlamine contents 2 h after intraperitoneal injection of -methyl-p-tyrosine (250 mg/kg), an inhibitor of tyrosine hydroxylase. We observed that the catecholamine contents in kaolin-induced hydrocephalus were not significantly different from control values. Following injection of -methyl-p-tyrosine, there was decrease in levels of catecholamines in both control and hydrocephalic rats. This decrease was, however, significantly less in induced hydrocephalus than in control animals. This result suggested that in hydrocephalus, the activities of norepinephrinergic and dopaminergic neurons are reduced. 相似文献
25.
Hery?Wijayanto Yuriko?Hirai Yosirou?Kamanaka Akira?Katho Dondin?Sajuthi Hirohisa?HiraiEmail author 《Chromosome research》2005,13(7):715-722
The course of chromosome evolution in small apes is still not clear, though painting analyses have opened the way for elucidating
the puzzle. Even the C-banding pattern of the lar-group of gibbons (the genus Hylobates) is not clarified yet, although our previous studies suggested that lar-group gibbons have a unique C-banding pattern. We
therefore made observations to establish C-banded karyotypes of the agile gibbons included in the lar-group. The data were
compared with those of siamangs (the genus Symphalangus), which carry distinctive C-bands, to determine the chromosomal patterns in each group. C-banded chromosomes of agile gibbons
showed several terminal, interstitial and paracentric bands, whose patterns are specific for each chromosome, whereas the
C-bands of siamangs were located only at the terminal and centromeric regions in most chromosomes. Moreover, the C-bands of
agile gibbons and siamangs were shown to be G+C-rich and A+T-rich DNA, respectively, by DAPI/C-band sequential staining. Additionally,
PRINS labelling with a telomere primer revealed that agile gibbons have telomeric DNA only at chromosome ends where there
is no C-band (non-telomeric heterochromatin), whereas the telomeric DNA of siamangs is located in the terminal C-banded regions
(telomeric heterochromatin). Although the evolutionary mechanisms in small apes are still unknown, C-banding patterns and
distribution of telomeric DNA sequences should provide valuable data to deduce the evolutionary pathways of small apes. 相似文献
26.
27.
Bi X Gatanaga H Tanaka M Honda M Ida S Kimura S Oka S 《Journal of acquired immune deficiency syndromes (1999)》2005,38(1):1-4
The Dynabeads method showed the potential for enumerating CD4 T lymphocytes (CD4 count) in HIV-1-infected individuals. The large volume of Dynabeads required for 1 sample and complex procedure made the method expensive and not easy for use, however. To decrease the cost and simplify the procedure, we reduced the volume of the Dynabeads, added wash times, and skipped over the staining step so as to count the CD4 cells directly under an optical microscope. The CD4 count of 246 blood samples using our modified Dynabeads method (DynabeadsCD4) showed a significant correlation with that obtained by flow cytometry (FlowcytoCD4) (r = 0.91 [P < 0.0001]; slope = 1.03, intercept = -16). The sensitivity and specificity for a CD4 count less than 200 cells/microL were 79% and 94%, and for a CD4 count less than 350 cells/microL, the sensitivity and specificity were 95% and 88%, respectively. The positive and negative predictive values for a CD4 count less than 350 cells/microL were 97% and 83%, respectively. The systematic error was 8 cells/microL (95% confidence interval [CI]: 0.4-16). The cost of Dynabeads for 1 sample was less than $1.00; thus, the estimated cost per DynabeadsCD4 test is less than $3.00, including the cost of other disposable materials. Our modified method is simple, economic, and accurate enough to monitor antiretroviral therapy in resource-limited situations. 相似文献
28.
Tanaka M Hirabayashi Y Gatanaga H Aizawa S Hachiya A Takahashi Y Tashiro E Kohsaka T Oyamada M Ida S Oka S 《Scandinavian journal of immunology》1999,50(5):550-554
Previous studies have suggested that CD4+ T lymphocytes shift from the Th1 type to the Th2 type during disease progression in patients with the human immunodeficiency virus type-1 (HIV-1). In the present study, we used a modified method that allowed a direct measurement of intracellular cytokines in CD4+ CD8- T cells. A total of 48 HIV-1-infected (HIV+) and 16 HIV-1-uninfected (HIV-) individuals were studied. The percentages of CD4+ CD8- T cells producing interleukin-2 (IL-2), interferon-gamma (IFN-gamma), interleukin-4 (IL-4), or interleukin-5 (IL-5) in HIV+ and HIV- subjects were 23.6% versus 34.9% (P < 0.01), 13.7% versus 13.2%, 1.3% versus 1.0%, and 1. 2% versus 0.9%, respectively. The population of IL-2-producing cells decreased proportionately with reductions in CD4 counts (< 200/mm3, 200-500/mm3, and > 500/mm3 to 18.0%, 23.5%, and 30.5%, P < 0.05, respectively). There was an inverse correlation between the percentage of IL-2-producing cells and plasma viral load (r = - 0. 446, P < 0.05). However, the percentages of CD4+ CD8- T cells producing other cytokines were not different between HIV+ and HIV-. Our cross-sectional study demonstrated a decrease in IL-2-producing cells but not the Th1 to the Th2 shift in the CD4+ CD8- T cell population in the moderate and advanced stages of HIV-1-infection. 相似文献
29.
N Ida S Sakurai T Hosaka K Hosoi T Kunitomo Y Matsuura M Kohase 《Journal of immunological methods》1990,133(2):279-284
An enzyme-linked immunosorbent assay has been developed to measure human interleukin-6. The assay, based on the avidin-biotin amplified two-step sandwich method, is quick (requiring 4.5 h), sensitive (detecting 9.5 pg/ml) and satisfactory in reproducibility and specificity. It shows good correspondence with the results of bioassays, and it is not affected by serum and plasma components. These results indicate that this ELISA is suitable for application to clinical samples, which is a major advantage over the widely used bioassays. 相似文献
30.