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41.
42.
Seiitsu Ono Takashi Imai Shigeru Munakata Keiichi Takahashi Fumio Kanda Kazuki Hashimoto Takahiko Yamano Natsue Shimizu Koichi Nagao Mitsuo Yamauchi 《Journal of the neurological sciences》1998,160(2):565-147
During the last 10 years, we have demonstrated morphological and biochemical abnormalities of skin extracellular matrices in amyotrophic lateral sclerosis (ALS). However, currently little is known concerning collagen of the spinal cord in ALS. We measured the amount of collagen and characterized collagen at light and electron microscopic levels in posterior funiculus, posterior half of lateral funiculus and anterior horn of cervical enlargement of the spinal cord obtained from ten patients with ALS, 11 patients with other neurologic diseases (control group A), and ten patients without neurologic ones (control group B). In posterior half of lateral funiculus and anterior horn, (1) by light microscopy, there was no significant difference in vessel wall area between ALS patients and control groups A and B; (2) ultrastructurally, collagen bundles were more fragmented and widely separated, and the fibrils were randomly oriented in the perivascular space of capillaries in ALS patients, which were not observed in any areas of control groups or in posterior funiculus of ALS patients; and (3) the collagen contents in ALS were significantly lower (P<0.001 and P<0.001, respectively) than those in control groups A and B. Fragmented and widely separated collagen bundles in the interstitial tissue surrounding capillaries and markedly decreased amount of collagen in posterior half of lateral funiculus and in anterior horn of ALS could be related to the degeneration of the upper and lower motor neurons in the spinal cord in ALS, that is, selective neuronal vulnerability in ALS. 相似文献
43.
44.
M Hayashi J Kimura K Yamaki Y Suwabe M Dozen Y Imai S Oh-ishi 《Thrombosis research》1987,48(3):299-310
PAF-likely activity, detected as aggregation of washed platelets, was found in the exudate of rats with pleurisy induced by phorbol myristate acetate (PMA, 1 nmol). At 30 min after the injection of PMA, 400-500 pg of PAF was detected in the pleural exudate. An extract of the exudate was made and analysed by HPLC and by rabbit platelet aggregation. The activity was characterized as that of PAF as a result of the inhibition seen with the PAF-antagonist CV-3988 and the loss of activity by treatment with phospholipase A2. Indirect evidence was previously reported in that CV-3988 suppressed the pleural fluid accumulation in the pleurisy induced by PMA. Taken together these facts it indicates that PAF could be an important mediator of acute inflammation, especially of the plasma exudation resulting from an increase in vascular permeability. Evidence that pleural cells produce PAF was also examined in an in vitro experiment. PAF was found in the supernatant and cellular fractions of the incubation mixture of the pleural cells from normal rats when stimulated by PMA (1 microM) or A23187 (5 microM), and the results indicate that the pleural cells produce PAF and release a portion of it. 相似文献
45.
46.
Seiji Nakata Jin Sato Kyoichi Imai Hidetoshi Yamanaka Yoshio Ichinose 《International journal of urology》1995,2(3):191-197
Background Prostate cancer is rare in Asia, but the number of patients is increasing in Japan. We conducted an epidemiological study of prostate cancer in Gunma Prefecture, Japan, to investigate the trends and characteristics of the disease.
Methods: The subjects were 1.411 prostate cancer patients newly diagnosed between 1985 and and 656 patients who died from prostate cancer between 1981 and 1992. The incidence and mortality rates were calculated by year, demographic region and age.
Results: The yearly incidence rate showed an increase but the mortality rate showed no marked fluctuations. There was no significant difference between urban and ruraI districts in either incidence or mortality rate. The incidence rate tended to be high in the northern part of the prefecture, but no marked variation in mortality rate was seen. The incidence and mortality rates in districts with a history of manganese mining were high compared to those in districts without mining. In contrast, the incidence and mortality rates in districts with a history of zinc mining were comparatively lower. Both incidence and mortality rates showed a marked increase with age. The age-specific incidence showed a double logarithmic relationship to age.
Conclusions: The increase of the yearly incidence rate might be due to changes in lifestyle and environmental factors, improved diagnostic techniques, and increased awareness among the general public regarding prostate disease. Further investigation is needed to clarify the pattern and the causes of regional differences in the incidence and mortality rates. The possibilities that manganese and zinc might be related to prostatic carcinogenesis are suggested. Int J Urol 1995:2:191–197 相似文献
Methods: The subjects were 1.411 prostate cancer patients newly diagnosed between 1985 and and 656 patients who died from prostate cancer between 1981 and 1992. The incidence and mortality rates were calculated by year, demographic region and age.
Results: The yearly incidence rate showed an increase but the mortality rate showed no marked fluctuations. There was no significant difference between urban and ruraI districts in either incidence or mortality rate. The incidence rate tended to be high in the northern part of the prefecture, but no marked variation in mortality rate was seen. The incidence and mortality rates in districts with a history of manganese mining were high compared to those in districts without mining. In contrast, the incidence and mortality rates in districts with a history of zinc mining were comparatively lower. Both incidence and mortality rates showed a marked increase with age. The age-specific incidence showed a double logarithmic relationship to age.
Conclusions: The increase of the yearly incidence rate might be due to changes in lifestyle and environmental factors, improved diagnostic techniques, and increased awareness among the general public regarding prostate disease. Further investigation is needed to clarify the pattern and the causes of regional differences in the incidence and mortality rates. The possibilities that manganese and zinc might be related to prostatic carcinogenesis are suggested. Int J Urol 1995:2:191–197 相似文献
47.
Clinical similarities of hereditary progressive/dopa responsive
dystonia caused by different types of mutations in the GTP
cyclohydrolase I gene
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Y. Tamaru M. Hirano H. Ito J. Kawamura S. Matsumoto T. Imai S. Ueno 《Journal of neurology, neurosurgery, and psychiatry》1998,64(4):469-473
OBJECTIVE—Hereditary progressive dystonia withpronounced diurnal fluctuation ((HPD)/dopa responsive dystonia (DRD))is a childhood onset dystonia which responds to levodopa. Variousclinical signs and symptoms of HPD/DRD have been recognised to date.Mutations in the GTP cyclohydrolase I (GTP-CH-I) gene were recentlyidentified as the cause of HPD/DRD. In the present study, the GTP-CH-Igene and the clinical features of eight HPD/DRD patients from sixfamilies were analysed to determine the correlationsbetween clinical expression and the mutations in the GTP-CH-I gene.
METHODS—The exons, exon-intron junctions, and anindispensable part of the 5' flanking region of the GTP-CH-I gene weresequenced in the eight clinically diagnosed patients with HPD/DRD andtheir asymptomatic parents.
RESULTS—Three independent mutations in theGTP-CH-I gene were found in three patients. One of the patients and herasymptomatic mother were heterozygous for a novel mutation at theinitiation codon. The three patients with dissimilar GTP-CH-I mutationsexhibited similar clinical features. The other five patients withnormal sequences presented several features not manifested by the three patients with the mutations. No mutation was found in the 5' flanking region of any patients or their parents.
CONCLUSIONS—A novel initiation codon mutation wasfound in a Japanese patient with HPD/DRD. The clinical manifestationscommon to the patients with HPD/DRD with a mutated GTP-CH-I gene werealso identified. Although focal manifestations of HPD/DRD associatedwith the mutations of this gene will be broadened, it is inferred thatthese clinical features are fundamental to HPD/DRD caused by mutationsin this gene.
相似文献
METHODS—The exons, exon-intron junctions, and anindispensable part of the 5' flanking region of the GTP-CH-I gene weresequenced in the eight clinically diagnosed patients with HPD/DRD andtheir asymptomatic parents.
RESULTS—Three independent mutations in theGTP-CH-I gene were found in three patients. One of the patients and herasymptomatic mother were heterozygous for a novel mutation at theinitiation codon. The three patients with dissimilar GTP-CH-I mutationsexhibited similar clinical features. The other five patients withnormal sequences presented several features not manifested by the three patients with the mutations. No mutation was found in the 5' flanking region of any patients or their parents.
CONCLUSIONS—A novel initiation codon mutation wasfound in a Japanese patient with HPD/DRD. The clinical manifestationscommon to the patients with HPD/DRD with a mutated GTP-CH-I gene werealso identified. Although focal manifestations of HPD/DRD associatedwith the mutations of this gene will be broadened, it is inferred thatthese clinical features are fundamental to HPD/DRD caused by mutationsin this gene.
相似文献
48.
Expression of intercellular adhesion molecule-1 on transitional cell cancer. Possible significance in immunity against tumor cells. 总被引:1,自引:0,他引:1
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Y. Tomita H. Watanabe H. Kobayashi T. Nishiyama S. Tsuji K. Imai T. Abo M. Fujiwara S. Sato 《The American journal of pathology》1993,143(1):191-198
Immunohistochemical examination demonstrated expression of intercellular adhesion molecule-1 (ICAM-1) on 17 of 44 transitional cell cancers (TCCs) but not on normal transitional cells. ICAM-1 was frequently expressed in higher stage tumors, especially in those with abundant immune cells scattered within tumor. Analysis of infiltrating immune cells showed that they were composed mainly of T lymphocytes and a smaller number of macrophages bearing the lymphocyte function-associated antigen-1 (LFA-1). Expression of ICAM-1 on transitional cell cancer cell lines was augmented by in vitro treatment with interferon-gamma, tumor necrosis factor-alpha, and interleukin-1 beta. Furthermore, Northern blot analysis revealed higher quantities of a 3.3-kb RNA in T24 cells exposed to interferon-gamma or tumor necrosis factor-alpha. These results suggest that the expression of ICAM-1 on transitional cell cancers might be modified by cytokines produced by infiltrating immune cells, which might facilitate immune responses against cancer cells. 相似文献
49.
Masami Hamaguchi Takaharu Ishibashi Naoki Katsumata Akio Mitomi Shoichi Imai 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1992,6(6):611-622
Summary In beagle dogs anesthetized with enfluranenitrous oxide, effects of sodium nitroprusside (SNP; MR7S1) and nitroglycerin (NTG) on hemodynamics and main organ circulation were studied to evaluate their effectiveness and safety as hypotensive agents during anesthesia. SNP (MR7S1) infusion (1–10 g/kg/min) decreased arterial blood pressure in a dose-dependent manner. The hypotension was stable during the infusion. After discontinuation of infusion, the blood pressure rapidly returned to the initial level. The hypotension was associated with decreases in cardiac output and total peripheral resistance. NTG infusion (3–10 g/kg/min) decreased arterial blood pressure, too, but the hypotension was less marked and not dose dependent, and the recovery was slower. Neither drug changed the heart rate. Infusion of SNP (MR7S1) and NTG did not change the hypotension induced by the injection of adenosine, SNP, and NTG. Furthermore, cerebral blood flow, cerebral oxygen consumption, and renal blood flow were unchanged during the hypotension produced by either drug. Coronary blood flow was decreased, but this was due to decreases in cardiac oxygen consumption. In conclusion, SNP (MR7S1) is superior to NTG as a hypotensive agent during anesthesia in efficacy, clear dose dependency, and rapid recovery. The hypotension induced by NTG as well as SNP (MR7S1) seems to have no undesirable effects on the circulation of important organs. 相似文献
50.
N Yamanaka T Imai J Miyazaki K Umezu G Kawabata K Ghoji H Yasuno H Okada S Kamidono 《Hinyokika kiyo. Acta urologica Japonica》1989,35(4):587-591
Although ileal conduit diversion is widely accepted in the treatment of the patients undergoing radical cystectomy, many patients would prefer other alternatives which allow continence. and urination through the urethra. We describe a new procedure in which a segment of detuburalized right colon is used as a continent reservoir. Eight patients, 7 after radical cystectomy for bladder cancer and one after total exenteration for rectal cancer, have undergone colon bladder replacement. New created bladder had a capacity of 300 to 600 ml. All patients could pass urine through the urethra but one is on self-catheterization. Five of the 8 patients had no residual urine. Three months after operations 4 were totally continent and 3 were satisfactorily dry during daytime but slightly enuretic. Excretory urography showed no abnormalities in their upper urinary tract. Considering the "quality of life' of a patient, this procedure can be an ideal option for selected patients. 相似文献