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1.
Principle for video-assisted thoracic surgery.   总被引:2,自引:0,他引:2  
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2.
To evaluate the number and function of suppressor T cells in children with minimal change nephrotic syndrome (MCNS), we performed an inhibition test of rosette formation and measured leukocyte procoagulant activity. The number of histamine H2 receptor-bearing T lymphocytes (histamine H2 R+ lymphocytes) was markedly decreased at the onset of MCNS but gradually increased and was normalized following steroid therapy. The production of leukocyte procoagulant activity by normal T lymphocytes was abolished by incubation with patient's lymphocytes. However, pretreatment of the normal T lymphocytes with cimetidine markedly decreased the suppression. The results suggest an abnormality in the histamine H2 receptors on the patient's suppressor T lymphocytes.  相似文献   
3.
The experimental system utilized in investigating the correlation between the chemical structures of muramyl peptides and their protective activities in the sepsis type of systemic infections caused by Escherichia coli was applied in evaluating the enhancement of resistance to infection induced by 32 synthetic glycopeptide analogs, including 6-O-acyl derivatives and 1-alpha-O-benzyl derivatives of muramyl dipeptide (N-acetyl muramyl-L-alanyl-D-isoglutamine). In assessing the 6-O-acyl derivatives of muramyl dipeptide, we found that the degree of protective activity was attributable to the kinds of fatty acids introduced. Acylation of the 6-hydroxy group on the muramic acid moiety in muramyl dipeptide with natural mycolic acid or a synthetic fatty acid possessing either an alpha-branched or an alpha-branched, beta-hydroxylated group resulted in a decrease in or a disappearance of the protective activity of muramyl dipeptide. Acylation with a normal fatty acid or an iso fatty acid resulted in a retention or enhancement of muramyl dipeptide activity. The activity of acylated derivatives containing linear fatty acids was stimulated by increasing the chain length up to 18 carbon atoms. The highest degree of protective activity occurred with the derivatives acylated with straight-chain fatty acids, particularly with the derivatives acylated with palmitic acid and arachidic acid. Benzylation of the 1-hydroxy group of muramyl dipeptide resulted in a decrease in or a loss of protective activity.  相似文献   
4.
The number of complement receptor for C3b (CR1) molecules in erythrocytes from patients with renal diseases was measured by an immunoradiometric assay using monoclonal antibodies against CR1. IgA nephritis patients with high serum creatinine value (Scr) showed markedly elevated levels of CR1, whereas patients with normal Scr had normal CR1 levels. A similar increase in CR1 number was observed in membranoproliferative glomerular nephritis with high Scr. CR1 of these patients functioned normally as a cofactor of C3b inactivator in cleaving immune complex-bound C3b. In contrast, a high frequency (5/6) of negative staining of glomerular CR1 was observed in IgA nephritis patients with high Scr by immunofluorescence study. We postulate that the disease-associated, acquired factors at least in part contribute to the abnormal expression of CR1: elevated levels in erythrocytes and defective expression on glomeruli.  相似文献   
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A Koyama  H Inage  M Kobayashi  M Narita    S Tojo 《Immunology》1986,58(4):529-534
The effect of chemical cationization of antigen on the glomerular localization and formation of immune complexes (IC) was investigated utilizing the models of acute accelerated and chronic serum sickness nephritis in rabbits. In acute accelerated serum sickness, neither antibody nor antigen was detected in the glomerulus before the second injection of antigen. At 15 min after the challenge, rabbits given cationized BSA developed IC deposition along the peripheral capillary walls, whereas no IC deposition was found in rabbits given native BSA. In chronic serum sickness, rabbits injected with a high dose (5 mg/rabbit/day), but not a low dose (500 micrograms/rabbit/day) of cationized BSA developed membranous nephropathy with severe proteinuria. In the group given cationized BSA, the levels and avidity of antibodies were lower than in the group given native BSA. Sucrose density gradient analysis of the complexes composed of 125I-cationized BSA showed that IC formed in vivo were slightly larger than 7S. These antibody characteristics, i.e. low precipitation and low avidity, continued from early on to the late period of immunization. These results suggest that chemical cationization altered the immunogenicity of the antigen and resulted in the formation of antibody of low precipitability and low avidity, even during long-term immunization.  相似文献   
7.
Background: In a previous paper, we reported that retinal blood flow (RBF) ceased immediately after injection of 1 nmol endothelin-1 (ET-1) and no recovery of RBF was detected for at least 50 min. In this study, we confirmed the same duration of RBF cessation and measured choroidal blood flow (CBF) for 180 min. Methods: We measured CBF in a rabbit model of transient complete obstruction of retinal vessels induced by intravitreal injection of a high dose of ET-1, using the hydrogen clearance method. We also investigated the effects of intravitreal injection of ET-1 on intraocular pressure (IOP), blood pressure, pulse rate and blood gases. Results: CBF was significantly greater in the ET-1-injected eyes than in the control eyes 40–130 min after injection of ET-1 (P < 0.05). The maximal CBF ratio in the ET-1-injected eyes was 128 ± 7.4% at 40 min. CBF decreased to the pre-injection level at 140 min after the injection of ET-1. There was no significant change in blood pressure, pulse rate and blood gases throughout this experiment, and there was no significant difference in IOP between ET-1-injected eyes and control eyes. Conclusion: It seems likely that the increase in CBF resulted from some local mechanisms of control that compensated for the decrease in RBF induced by intravitreal injection of ET-1. This model may be useful for investigation of the regulatory system of intraocular circulation, including endothelin receptors.  相似文献   
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PURPOSE: To determine the prevalence of use of complementary and alternative medicine (CAM) by patients with cancer in Japan, and to compare the characteristics of CAM users and CAM nonusers. PATIENTS AND METHODS: A questionnaire on cancer CAM and the Hospital Anxiety and Depression Scale were delivered to 6,607 patients who were treated in 16 cancer centers and 40 palliative care units. RESULTS: There were 3,461 available replies for a response rate of 52.4%. The prevalence of CAM use was 44.6% (1,382 of 3,100) in cancer patients and 25.5% (92 of 361) in noncancer patients with benign tumors. Multiple logistic regression analysis determined that history of chemotherapy, institute (palliative care units), higher education, an altered outlook on life after cancer diagnosis, primary cancer site, and younger age were strongly associated with CAM use in cancer patients. Most of the CAM users with cancer (96.2%) used products such as mushrooms, herbs, and shark cartilage. The motivation for most CAM use was recommendation from family members or friends (77.7%) rather than personal choice (23.3%). Positive effects were experienced by 24.3% of CAM users with cancer, although all of them received conventional cancer therapy concurrently. Adverse reactions were reported by 5.3% of cancer patients. CAM products were used without sufficient information by 57.3% of users with cancer and without a consultation with a doctor by 60.7% of users. CONCLUSION: This survey revealed a high prevalence of CAM use among cancer patients, without sufficient information or consultation with their physicians. Oncologists should not ignore the CAM products used by their patients because of a lack of proven efficacy and safety.  相似文献   
10.
Introduction:Uterine fibroids, which are common benign tumors, rarely cause acute complications. We herein report a case of hemoperitoneum associated with uterine fibroid that could be diagnosed preoperatively with contrast-enhanced computerized tomography (CT).Patient concerns:A 48-year-old woman with uterine fibroid developed extremely severe lower abdominal pain on the first day of her menstrual period.Diagnosis:Ultrasonography and contrast-enhanced CT revealed a uterine fibroid and extravasation from the dilated vessels of the uterine fibroid.Intervention:Emergent abdominal hysterectomy was performed.Outcomes:The total amount of bleeding was 4,600 mL. Intraoperative blood salvage (1,357 mL), 6 units of red blood cells, 4 units of fresh frozen plasma, and 20 units of platelet concentrates were transfused. The postoperative course was uneventful. Pathological examination confirmed a benign uterine fibroid.Conclusion:CT could be useful to determine a diagnosis for bleeding from ruptured subserosal uterine fibroid.  相似文献   
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