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61.
Hajime Kuhara Kazunori Ikei Takashi Wakabayashi Hidemasa Kishimoto 《Pathology international》1986,36(7):1083-1088
A 58-year-old man with liposarcoma originating from the right paratesticular area was reported. Histologically, liposarcoma showed a well-differentiated sclerosing type. Coexistence of transitional cell carcinoma of the urinary bladder and liposarcoma was also revealed. The cases of paratesticular liposarcoma in the literature are briefly reviewed. 相似文献
62.
Makoto Nagasaki Takayuki Harada Ikuko Torii Akinobu Nakano Hiroshi Furuya Junichi Tanaka Kanji Hirai Shigeru Morikawa 《Pathology international》1994,44(12):850-856
A case of acquired immunodeficiency syndrome (AIDS) with preceding aplastic anemia is reported. The patient was a 36 year old female who had been diagnosed as having aplastic anemia 10 years before and thereafter had received multiple transfusions. Human immunodeficiency virus (HIV)-seropositivity was revealed 10 months prior to her death, but no particular clinical signs indicating HIV infection, pre-AIDS or onset of AIDS were recognized before serological diagnosis, although the slow progression of leukopenia was noted along with thrombocytopenia. Her general condition deteriorated during the last 10 months accompanied by an acute decrease In the CD4/CD8 ratio. Autopsy revealed full-blown AIDS: systemic aspergillosis, progressive multifocal leukoencephalopathy, Epstein-Barr virus-related B cell lymphoma arising in the diaphragm and severe lymphocyte depletion in the lymph nodes and spleen. Markedly hypo-plastic bone marrow was considered to be primarily attributable to the aplastic anemia but the affection of AIDS was not excluded. The possible transmission route of HIV and the effect of the preceding aplastic anemia on the infection and clinical course of AIDS are discussed. 相似文献
63.
Wakamatsu T Saito T Hayashi J Takeichi T Kitamoto K Aizawa K 《Medical molecular morphology》2005,38(4):225-232
Flexible treatments for intimal hyperplasia after angioplasty are still needed. The aim of this study was to demonstrate the
long-term effects of vascular photodynamic therapy with talaporfin sodium on intimal hyperplasia following interventional
injury. Intimal hyperplasia was induced by balloon distension injury to the carotid artery in 31 rabbits. Talaporfin, 5.0 mg/kg,
was delivered systemically immediately after balloon injury. The injury site was irradiated with a diode laser light of wavelength
664 nm using a fluence of 50 J/cm2 after 30 min. At day 3 and weeks 3, 6, 9, 15, and 25 after photodynamic therapy, the treated artery of each rabbit was excised
and examined immunohistochemically. Thirty minutes after talaporfin administration, drug fluorescence was found only in the
balloon-injured carotid artery wall. At 3 days, no smooth muscle cells were seen in the media of the photodynamic therapy-treated
arterial segments. Intimal hyperplasia developed progressively in the balloon-injured and untreated segments; however, in
the segments treated with photodynamic therapy, intimal hyperplasia was markedly suppressed until 25 weeks and the media was
repopulated by smooth muscle cells without macrophages. Vascular photodynamic therapy with talaporfin may be used to inhibit
restenosis after vascular intervention.
An erratum to this article is available at . 相似文献
64.
Kazuo Watanabe Atsuko Saito Hironao Wakabayashi Takanori Kawaguchi Toshimitsu Suzuki 《Pathology international》1991,41(6):461-465
Two autopsy cases of leiomyosarcoma of the liver in a 49-year old female and 63-year-old male are reported. Both of the liver tumors showed electron microscopically dense patches in the cytoplasm and intermediate junctions between the tumor cells, suggesting a smooth muscle cell origin, irrespective of their different histological features. The nature of both tumors was confirmed by positive immunoreactivity for muscle-specific actin in the tumor cells, whereas desmin immunoreactivity was labile in both cases, showing a higher diagnostic value of the former compared with the latter in these leiomyosarcomas. Both cases, showed extensive distant metastases in spite of an evident difference in their mitotic indices, indicating that this index is not reliable for judging the metastatic potential of these tumors. Acta Pathol Jpn 41: 461–465, 1991. 相似文献
65.
Toshiie Sakata Masataka Fukushima Junichi Kodama Hideaki Fuchimoto 《Physiology & behavior》1977,19(3):397-400
Running-wheel activity for 24 hr and activity patterns were studied during chronic theophylline administration. Theophylline altered the normal relations between activity level and illumination. Dark-time activity was decreased to approximately 50% and 24 hr activity was unaffected. These observations were consistent with previous results showing that theophylline suppressed dark-time feeding but had no effect on 24 hr food intake. A possible mechanism to account for these results may be dependent on levels and turnover of brain norepinephrine. 相似文献
66.
Tokuo Ogawa Junichi Sugenoya Norikazu Ohnishi Keiko Natsume Kazuno Imai Yoshikazu Kandori Akira Ishizuka Atsushi Osada 《European journal of applied physiology》1993,67(4):354-359
Summary We have examined the nonparallel changes in tampanic membrane temperatures (T
ty) from the two ears in response to various changes in body and head positions. Upon assuming a lateral recumbent position, the T
ty on the lower side increased while that on the upper side decreased. Pressure application over a wide area of the lateral chest only caused inconsistent and obscure asymmetric changes in T
ty. A lateral flexion of the head with the subject sitting upright and a rotation of the head to the side in a supine position induced an increase in the T
ty on the lower side compared to that on the upper side. The temperature and blood flow of the forehead often decreased on the lower side and increased on the upper side, although such responses were not always concomitant with the asymmetric changes in T
ty. A dorsal flexion of the head with the subject in a reclining position caused a slight increase in the T
ty, whereas raising the head upright induced a slight decrease in them. Two additional experiments were carried out with single photon emission computed tomography using 99mTc-hexamethylpropyleneamine oxime as tracer, and a slight, relative decrease in counts was noted in the right hemisphere during rotation of the head to the right. These results would strongly suggest that unilateral increases and decreases in T
ty could have been caused by one-sided decreases and increases, respectively, in blood flow to the brain and/or the tympanic membrane, induced by a vasomotor reflex involving vestibular stimulation. 相似文献
67.
The effect of celecoxib, a cyclooxygenase-2 inhibitor, in familial adenomatous polyposis 总被引:105,自引:0,他引:105
Steinbach G Lynch PM Phillips RK Wallace MH Hawk E Gordon GB Wakabayashi N Saunders B Shen Y Fujimura T Su LK Levin B Godio L Patterson S Rodriguez-Bigas MA Jester SL King KL Schumacher M Abbruzzese J DuBois RN Hittelman WN Zimmerman S Sherman JW Kelloff G 《The New England journal of medicine》2000,342(26):1946-1952
BACKGROUND: Patients with familial adenomatous polyposis have a nearly 100 percent risk of colorectal cancer. In this disease, the chemopreventive effects of nonsteroidal antiinflammatory drugs may be related to their inhibition of cyclooxygenase-2. METHODS: We studied the effect of celecoxib, a selective cyclooxygenase-2 inhibitor, on colorectal polyps in patients with familial adenomatous polyposis. In a double-blind, placebo-controlled study, we randomly assigned 77 patients to treatment with celecoxib (100 or 400 mg twice daily) or placebo for six months. Patients underwent endoscopy at the beginning and end of the study. We determined the number and size of polyps from photographs and videotapes; the response to treatment was expressed as the mean percent change from base line. RESULTS: At base line, the mean (+/-SD) number of polyps in focal areas where polyps were counted was 15.5+/-13.4 in the 15 patients assigned to placebo, 11.5+/-8.5 in the 32 patients assigned to 100 mg of celecoxib twice a day, and 12.3+/-8.2 in the 30 patients assigned to 400 mg of celecoxib twice a day (P=0.66 for the comparison among groups). After six months, the patients receiving 400 mg of celecoxib twice a day had a 28.0 percent reduction in the mean number of colorectal polyps (P=0.003 for the comparison with placebo) and a 30.7 percent reduction in the polyp burden (the sum of polyp diameters) (P=0.001), as compared with reductions of 4.5 and 4.9 percent, respectively, in the placebo group. The improvement in the extent of colorectal polyposis in the group receiving 400 mg twice a day was confirmed by a panel of endoscopists who reviewed the videotapes. The reductions in the group receiving 100 mg of celecoxib twice a day were 11.9 percent (P=0.33 for the comparison with placebo) and 14.6 percent (P=0.09), respectively. The incidence of adverse events was similar among the groups. CONCLUSIONS: In patients with familial adenomatous polyposis, six months of twice-daily treatment with 400 mg of celecoxib, a cyclooxygenase-2 inhibitor, leads to a significant reduction in the number of colorectal polyps. 相似文献
68.
Adenosine A1 receptor-mediated presynaptic inhibition of GABAergic transmission in immature rat hippocampal CA1 neurons 总被引:4,自引:0,他引:4
In the mechanically dissociated rat hippocampal CA1 neurons with native presynaptic nerve endings, namely "synaptic bouton" preparation, the purinergic modulation of spontaneous GABAergic miniature inhibitory postsynaptic currents (mIPSCs) was investigated using whole-cell recording mode under the voltage-clamp conditions. In immature neurons, adenosine (10 microM) reversibly decreased GABAergic mIPSC frequency without affecting the mean current amplitude. The inhibitory effect of adenosine transmission was completely blocked by 8-cyclopentyl-1,3-dipropylxanthine (DPCPX, 100 nM), a selective Alpha(1) receptor antagonist, and was mimicked by N(6)-cyclopentyladenosine (CPA, 1 microM), a selective Alpha(1) receptor agonist. However, CPA had no effect on GABAergic mIPSC frequency in postnatal 30 day neurons. N-ethylmaleimide (10 microM), a guanosine 5'-triphosphate binding protein uncoupler, and Ca(2+)-free external solution removed the CPA-induced inhibition of mIPSC frequency. K(+) channel blockers, 4-aminopyridine (100 microM) and Ba(2+) (1 mM), had no effect on the inhibitory effect of CPA on GABAergic mIPSC frequency. Stimulation of adenylyl cyclase with forskolin (10 microM) prevented the CPA action on GABAergic mIPSC frequency. Rp-cAMPS (100 microM), a selective PKA inhibitor, also blocked the CPA action. It was concluded that the activation of presynaptic Alpha(1) receptors modulates the probability of spontaneous GABA release via cAMP- and protein kinase A dependent pathway. This Alpha(1) receptor-mediated modulation of GABAergic transmission may play an important role in the regulation of excitability of immature hippocampal CA1 neurons. 相似文献
69.
Junichi Tanaka Arthur P. Arnold 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,94(2):301-307
The bulbocavernosus (BC) reflex, produced in the BC motor nerve in response to electrical stimulation of the contralateral pudendal sensory nerve, was investigated in intact, castrated, and testosterone-treated castrated male rats under urethane anesthesia. No significant group differences in the reflex latency, sensory or motor conduction velocity, or central delay were observed. A conditioning pulse to the pudendal sensory nerve caused suppression of the averaged antidromic field potential recorded in the contralateral spinal nucleus of the bulbocavernosus (SNB) after stimulation of the SNB axons in the BC motor nerve. The suppression occurred at 6- to 35-ms intervals between shocks to pudendal sensory nerve and BC motor nerve, and was markedly smaller in castrated males than in the other two groups. In contrast, a conditioning pulse to the contralateral BC motor nerve had no effect on the SNB antidromic field potential. These results indicate that androgen modulates the efficacy of synaptic transmission onto SNB motoneurons or other neurons involved in the BC reflex. 相似文献
70.