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71.
Akihiro Ito Tadateru Takahashi Hiromitsu Watanabe Peter Osa Ogundigie Taro Okamoto 《Cancer science》1992,83(10):1052-1056
Mouse liver tumors occurring in C3H/HeN, C57BL/6N and C3B6F1 hybrid (C3H × C57BL) were studied following 252 Cf fission neutron irradiation. Three strains of mice of both sexes (about 30 mice/group) were irradiated once with 252 Cf at doses of 0,12.5, 50 and 200 cGy. The groups were observed for 13 months after irradiation. The incidence of liver tumors in the non-irradiated controls was 0% in both sexes of CS7BL/6N, 11.7% in males and 0% in females of C3B6F1 and 39.5% in males and 11.4% in females of C3H/HeN mice. In the four strains of mice thus far studied, including B6C3F1 hybrid (CS7BL × C3H) which was previously studied, 252 Cf irradiation has increased the tumor incidence dose-dependently in males and in females, but less effectively in females. The mean number and size of liver tumors were clearly correlated with tumor incidence. The incidence was always highest in C3H/HeN mice of both sexes, followed by B6C3F1, C3B6F1 and C57BL/6N mice. The influence of sex hormones was studied in B6C3F1 mice of both sexes after 200 cGy of 252 Cf irradiation. In males, the incidence of liver tumors was significantly decreased from 55.2% to 23.3% and 25.9% after orchidectomy, and in females it was slightly decreased from 27.6% to 14.8% and 18.8% after ovariectomy. Supplementation of testosterone in orchidectomized mice did not restore the occurrence of liver tumors. 相似文献
72.
The purpose of this study was to clarify the bronchodilating effect of pirenzepine (PZ) and to verify its mechanism. Ten asthmatic patients (6 men, 4 women: aged 20 to 65, 5 atopic 5 non-atopic) and ten non-asthmatic volunteers (8 men, 2 women: aged 25 to 60) were studied. Forced vital capacity (FVC), forced expiratory volume in one second (FEV1.0) and peak expiratory flow rate (PEFR) were measured after intravenous administration of 20 mg PZ. PZ increased FVC, FEV1.0 and PEFR significantly by 15%, 29% and 37% respectively in asthmatic patients (p less than 0.01). We also studied the effects of PZ on the contractile responses of tracheal smooth muscle to intra-arterially administered acetylcholine (ACh) and the electrical stimulation of the vagus nerves (VNS) using isometric technique in situ in 5 mongrel dogs. PZ significantly inhibited the contractile responses elicited with ACh at doses larger than 1000 micrograms/kg (p less than 0.01). PZ also significantly inhibited the contractile responses elicited by VNS at doses larger than 100 micrograms/kg (p less than 0.01). These data demonstrate that intravenously administered PZ dilates the airway in asthmatic patients and also suggest that the bronchodilating effect of PZ related to inhibition of the M1 and M3 muscarinic receptors. 相似文献
73.
W Higuchi Y Moriyama K Kishi T Koike A Shibata S Shinada I Tada A Miura 《Bone marrow transplantation》1991,7(2):163-166
We describe a patient with acute lymphoblastic leukemia (ALL) in whom hemopoiesis recovered after an autologous marrow graft purged by in vitro hyperthermia. A 17-year-old woman was diagnosed as having ALL in April 1985. After clinical remission was induced, marrow cells were harvested. The marrow cells were treated with hyperthermia at 42.0 degrees C for 1 h in the presence of alpha-interferon to eliminate residual leukemic cells, and then cryopreserved. In January 1990, during her fourth remission she was treated with busulfan and cyclophosphamide, and then received the thawed autologous marrow. Her hematopoietic recovery was prompt with normal trilineage regeneration without any life-threatening complications. She is in good health without evidence of a leukemic relapse at 6 months after autologous bone marrow transplantation. This case suggests that human multilineage progenitor cells retain self-renewal capacity in vivo even after treatment with heat and alpha-interferon in vitro followed by the freezing and thawing procedures. 相似文献
74.
Morito Nakayama MD Naoyuki Kataoka MD Yutaka Usui MD Naohiko Inase MD Shigemitsu Takayama MD Hirotaro Miura MD 《The Journal of emergency medicine》1992,10(6):729-734
When nasotracheal intubation with a fiberoptic bronchoscope is performed, the tube may be blocked in the nasal cavity or larynx, resulting in several complications including epistaxis and hoarseness. We review the causes and complications of tube blockage and discuss optimal techniques for minimizing it. 相似文献
75.
H Imai H Wakui T Ishino A Komatsuda Y Nakamoto A B Miura R Kobayashi 《Clinical nephrology》1992,37(4):169-176
IgA immune complexes and polymeric IgA are presumed to play important roles in the development and progression of IgA nephropathy. Complex-forming glycoprotein heterogenous in charge (protein HC), being inhibitors of neutrophilic chemotaxis, has been reported as binding to IgA. As a working hypothesis it was assumed that complexes of protein HC and IgA are present in glomeruli from IgA nephropathy patient in stable state. In this study, we examined the glomerular deposition of protein HC in 40 patients with IgA nephropathy and in 10 patients with non-IgA nephropathy. We used highly specific antibody against protein HC, that does not cross-react with alpha-1-microglobulin. An immunofluorescent study revealed that 10 out of the 40 patients (25%) showed an intensity of 1+, 16 (40%) showed weak positive (+/-), and the other 14 (35%) were negative. There was no deposition of protein HC in non-IgA nephropathy patients. Histopathological analysis demonstrated a significant correlation between the intensity of glomerular-deposited protein HC and pathological activity (p less than 0.005); the latter was defined as having either crescents in more than 15% of the remaining glomeruli (excluding global sclerotic glomeruli), or segmental necrosis or sclerosis in more than 30% of the remaining glomeruli. A significant correlation was observed between pathological activity and the intensity of deposited IgG, IgA and IgM (p = 0.01), and lambda chain (p less than 0.005). Considering anti-inflammatory activity of protein HC, these results suggest that protein HC cannot protect sufficiently acute inflammation or tissue damages due to co-deposited IgG and IgM and/or other factors.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
76.
Ryo Aeba Toshiyuki Katogi Kenichi Hashizume Yoshimi Iino Kiyoshi Koizumi Kentaro Hotoda Shinya Inoue Hideki Matayoshi Akihiro Yoshitake Ryohei Yozu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2003,51(7):302-307
OBJECTIVE: Severe aortic arch obstruction including an interrupted aortic arch in congenital complex heart anomalies remains a challenge in surgical management. METHODS: Treatment and outcomes in 75 consecutive patients who underwent an aortic arch repair as the first step of the staged repair protocol between 1975 and 2000 were reviewed. Their ages at repair ranged from 1 day to 8.5 months. RESULTS: Cross-sectional postoperative follow-up data were available in all the patients. The follow-up period ranged from 0 to 27.6 years (mean: 7.3 +/- 7.3 years). There were 20 postoperative hospital deaths (27%) and 7 late deaths. The Kaplan-Meier estimate of survival was 81.3% +/- 4.5% at 1 month, 68.0% +/- 5.4% at 1 year, 65.0% +/- 5.5% at 5 years, 63.1% +/- 5.7% at 10 years, 63.1% +/- 5.7% at 20 years. By Cox regression analysis, body weight of 2.5 kg or less is the only independent determinant of postoperative mortality (p = 0.04, multivariable odds ratio: 2.50, [95% confidence interval: 1.02-6.1]). The aortic arch morphology, the primary cardiac lesion, or date of operation did not reach a statistically significant level to show correlation with mortality. Reintervention to reconstruct the aortic arch was performed at 9 occasions in 8 of the 55 patients who survived the primary operation (14.5%). The Kaplan-Meier estimate of the reintervention-free rate was 91.3% +/- 4.2% at 5 years, 85.5% +/- 5.6% at 10 years, 75.6% +/- 8.2% at 20 years. Using multivariable Cox regression analysis, interrupted aortic arch (versus aortic coarctation) was the only independent predictor of a shorter time to reintervention (p = 0.001, multivariable odds ratio: 16.1, [95% confidence interval: 3.2-80.2]). CONCLUSIONS: The staged repair protocol was associated with significant limitations in patient survival and with the development of recurrent aortic arch obstruction. Thus, a primary repair protocol may serve as an alternate approach, especially in patients with low weight or with an interrupted aortic arch. 相似文献
77.
Follicular dendritic cells (FDC) in retroviral infection: host/pathogen perspectives 总被引:6,自引:0,他引:6
Gergory F. Burton Akihiro Masuda Sonya L. Heath Beverly A. Smith John G. Tew ras K. Szakal 《Immunological reviews》1997,156(1):185-197
Summary: Follicular dendritic cells (FDC) are found in the follicles of virtually all secondary lymphoid tissues. In health, these cells trap and retain antigens (Ag) in the form of immune complexes and preserve them for months in their native conformation. FDC thus serve as a long-term repository of extracellular Ag important for induction and maintenance of memory responses. In retroviral infection. FDC trap and retain large numbers of retroviral particles with profound effects on FDC. FDC-trapped retrovirus induces follicular hyperplasia, and conventional Ag trapped prior to infection are lost and new Ag cannot be trapped. Concomitantly, antibody-forming cells (AFC) specific for Ag lost from FDC decrease follow I by loss of specific serum antibody (Ab). Eventually, FDC die and follicular lysis occurs. From the pathogen perspective, binding to FDC is remarkably beneficial, bringing together virus and activated target cells that are highly susceptible to infection. Furthermore, FDC permit HIV to infect surrounding cells even in the presence of a vast excess of neutralizing Ab. Preliminary data suggest that FDC maintain virus infectivity - even when the virus cannot replicate. Thus retrovirus infection monopolizes FDC networks, thereby transforming the FDC Ag repository into a highly infectious retroviral reservoir. 相似文献
78.
79.
A rare case of suprasellar pituitary adenoma arising from the pars tuberalis in a 53-year-old woman is presented. The tumor was located exclusively above the diaphragma sellae, and no invasion into the sella turcica was noted. 相似文献
80.