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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
961.
H Shiozaki T Ide J Nakao T Imamura M Nakamura K Shimada Y Miura T Suda 《Japanese journal of cancer research》1992,83(5):499-504
LD78 is a cDNA newly isolated from human stimulated tonsillar lymphocytes. The expression of LD78 is related to inflammatory responses and its structure has a homology with macrophage inflammatory protein 1-alpha, which is known to have an inhibitory effect on murine CFU-S. Using a colony assay technique, we examined the effects of LD78 on human hemopoietic progenitors. The addition of doses of 100 ng/ml or more of LD78 suppressed the colony formation of KMT-2, a factor-dependent myelomonocytic cell line established from cord blood cells; this suppressive activity was neutralized by the addition of antibody against LD78. The same doses of LD78 suppressed the formation of neutrophil, macrophage, and megakaryocytic colonies which were supported by human interleukin-3 and erythropoietin; however, LD78 did not affect colony formation by either non-phagocytic mononuclear cells or sorted CD34+ cells. The conditioned medium of KMT-2 cells or peripheral blood mononuclear cells cultured with LD78 suppressed colony formation by CD34+ cells. From these findings, it is suggested that LD78 affects phagocytic cells and induces factors that are inhibitory for hemopoiesis. We consider LD78 to be a new cytokine that plays an inhibitory role in hemopoiesis. 相似文献
962.
E Kvist K E Sj?lin H Laursen T F Orntoft M A Sturmer 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》1992,100(7):650-654
In a retrospective study of 28 women and eight men with squamous cell metaplasia in different parts of the bladder, including the trigone, no histopathological differences were observed among the regions. All the five (female) patients with parakeratosis had a concomitant invasive bladder tumour. Thirty-eight% of all the patients had a simultaneous neoplastic tumour. The metaplastic lesions were investigated for keratin in 13 patients, and all were positive. In seven out of eight patients, the urothelium adjacent to the squamous cell metaplasia was also positive for keratin, indicating a direct transformation of the urothelium to squamous cell epithelium. The metaplastic cells were investigated for oestrogen receptors in five men and five women, and all were negative, suggesting no relationship between estrogens and squamous cell metaplasia of the bladder. Squamous cell metaplasia in the bladder is not considered a premalignant condition. However, metaplasia and neoplastic tumours are often associated with chronic tissue damage, and the presence of metaplasia may give a warning of conditions that can also cause cancer. 相似文献
963.
F J Skj?rten S H Brorson B Roald E H Str?m B Lund 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》1992,100(11):1001-1007
Fifty renal biopsies were studied by immunoelectron microscopy after embedding in a partly hydrophilic polyacrylic resin (LR White). Immunofluorescence studies were carried out on frozen sections of parallel tissue samples. Polyacrylic embedding gave good preservation of the renal ultrastructure and precise localization of immunoglobulin and C3c antibodies within glomerular electron-dense deposits. Non-specific staining of plasma proteins within vascular lumina could easily be detected. There was good correlation between immunoelectron and immunofluorescence microscopy. Immunoelectron microscopy is a very sensitive method, which can detect small amounts of antigen. More cases were, however, positive by immunofluorescence than by immunoelectron microscopy. This discrepancy may be explained by difference in sample size, and by difference in resolution of morphological details (electron microscopy versus fluorescence microscopy). 相似文献
964.
L Goedel-Meinen M Hofmann G Schmidt W Maier-Rudolph P Barthel A Schrag W Baedeker H Bl?mer 《Zeitschrift für Kardiologie》1991,80(3):187-193
This prospective study examined the influence of long-term amiodarone therapy on the parameters of the signal-averaged ECG and their relation to simultaneously derived Holter monitoring data. For this purpose, 23 patients with angiographically confirmed dilated cardiomyopathy or coronary heart disease and high-grade ventricular arrhythmias, in whom an average of four class I antiarrhythmic drugs had proven ineffective, were stabilized on amiodarone. Before the beginning of therapy, as well as after 2 months and, subsequently, every 3 months, a resting ECG, a signal-averaged ECG by Simson's method, and Holter monitoring were performed. Compared to the initial measurement, we found a significant increase in the duration of the total filtered QRS complex from an average of 114 +/- 24 ms to 127 +/- 35 ms, while the change in voltage did not reach the significance level. The incidence of late potentials remained largely constant under amiodarone; 10 patients showed a constant late potential, 12 patients had no late potential, and one patient with coronary heart disease developed a new late potential. In the long-term follow-up, we ascertained a relatively high responder rate under amiodarone between 41% and 81%. No relation could be detected between the results of the signal-averaged ECG and those of 24-h Holter monitoring. 相似文献
965.
L Papp A Kollár F Rényi-Vámos T Gy?ngy F Horkay L V Hermes E Moravcsik E Bodor Z Szabolcs Z Szabó 《Orvosi hetilap》1992,133(15):901-908
In Hungary valve replacement is still a major indication for heart surgery in adults. In the Cardiovascular Surgical Clinic of Semmelweis Medical University of Budapest from 1976 to 1990 2435 patients were operated for valve disease. Majority of the cases had single (aortic n = 856, mitral n = 912) or double (aortic + mitral n = 513) valve replacement. Over this 15 years period there have been many alterations in patients characteristics and surgical technique as well. In spite of the increasing mean age of patients the operative mortality has decreased (in the last 5 years period it was 2.7%, 5.5% and 7.9% in the three groups respectively). At the same time the number of patients requiring valve re-replacement or combined valve + coronary procedure has increased. The use of bioprosthetic valves has fallen below 10 percent from the 60--80 percent observed between 1976--1980. The analysis showes excellent surgical results in the field of valve replacement in Hungary. 相似文献
966.
The neutron capture reaction 10B(1n,4He)7Li produces two energetic particles, 4He2+ and 7Li3+ that are strongly cell toxic. Due to the short range of these nuclear fragments (5-9 microns) mainly those cells that have bound or internalized a 10B-containing substance are growth-inactivated. The most critical and difficult step in an efficient boron neutron capture therapy (BNCT) is the tumour targeting. It is today possible to synthesize a large number of boron compounds and conjugate them to tumour-seeking macromolecules, such as monoclonal antibodies or different polypeptides. The boron-containing substances presently considered for therapy are sulfhydryl boron hydride (BSH) and boron-phenylalanine, (BPA) for the treatment of gliomas and malignant melanomas respectively. Other boronated compounds considered are ligands for receptor-amplified tumour cells, antibodies for tumour cells with specific antigens and thioureas for treatment of melanotic melanomas. The required boron concentration is given by the relative dose due to neutron capture in 10B and that of the competing capture reactions in nitrogen and hydrogen. Capture in nitrogen produces protons with a range of about 10-11 microns and this gives a radiation dose to all cells in the neutron activated area. Calculations show that the local concentration of 10B near the critical radiation target, DNA, must be higher than 10 ppm (10 micrograms/g). Increased emphasis will be put on the development of combinations of treatments that fulfil the requirements for attacking the microscopic spread of the tumour. 相似文献
967.
968.
Takuo Fujita Masaaki Fukase Takao Shimada Hironosuke Yamamoto 《Journal of bone and mineral metabolism》1992,10(1):37-40
In addition to estrogen widely used all over the world for the prevention of postmenopausal osteoporosis, calcitonin and vitamin
D derivatives are commonly employed to treat established osteoporosis at higher age in Japan. In order to critically assess
the usefulness of vitamin D derivatives and calcitonin alone or in combination on the advancement of vertebral deformity at
higher age, 32 osteoporotic patients with vertebral deformity with the mean age of 79 were randomly divided into 4 groups
with indistinguishable age and severity of the vertebral deformity. Group 1 served as the control without specific medications
for osteoporosis. Group 2 was treated with 10 units elcatonin (eel calcitonin derivative) injected intramuscularly twice a
week. Group 3 was given 0.75 to 1.5μg/day 1α (OH) vitamin D3 orally. Group 4 was given a combination of treatments used in Groups 2 and 3.
In the lateral X-ray film of the spine taken prior to the test and every 6 months thereafter, the shape of the vertebral body
T8 through L4 was monitored by measuring the anterior, central and posterior heights. Decrease of the vertebral height ratio; anterior
or middle height/posterior or adjacent intact posterior height, by more than 20% of the original value or from above to below
0.80 both appeared to be inhibited during administration of 1α (OH) vitamin D3. Such effect seems to be augmented by simultaneous administration of elcatonin. Actual decrease of vertebral height ratio
values and the per cent fall from the original value significantly less in Groups 3 and 4 than in Group 1. Development of
vertebral deformity assessed by the changes of the vertebral height thus appears to decrease during treatment with 1α (OH) vitamin D3 especially together with calcitonin in established osteoporosis. 相似文献
969.
The effects of 20 weeks of physical fitness training in female patients with fibromyalgia. 总被引:7,自引:0,他引:7
During a period of 20 weeks 18 female patients with fibromyalgia participated in a 60-minute exercise program twice a week. A control group, comprising 17 patients, was told not to change their physical activity level. Eleven patients in the training group and fourteen in the control group completed the study. The results at entry were compared to those after 20 weeks, as well as being compared to the results of the control group. No statistically significant changes or differences in general pain, pain coping and fatigue were seen after 20 weeks. Improved dynamic endurance work performance for the upper extremity was found, however, in the training group, measured as the strength of the first (p = 0.01) and the last repetition (p = 0.003). These results differed from the results of the control group (p = 0.02 and p = 0.003). It is concluded that fibromyalgia patients may undergo low-intensity dynamic endurance training without experiencing exacerbation of their general pain and fatigue symptoms. 相似文献
970.
Changes in whole blood viscosity associated with hematocrit could be one of the pathways along which the cardiovascular disease (CVD) risk factors affect these diseases. Therefore, we studied in a nationwide survey comprising 514 apparently healthy Dutch elderly men and women aged 65-79 the possibility of any association between hematocrit and CVD risk factors (tobacco smoking, serum cholesterol, body mass index and blood pressure). Among men, diastolic blood pressure and total serum cholesterol were positively associated with hematocrit in both bivariate and multivariate regression analysis, whereas positive associations of hematocrit with body mass index and smoking were only significant (p < 0.05) in bivariate analysis. Among women, hematocrit was positively associated with body mass index and smoking. Except for smoking, which was associated with the mean corpuscular volume of the erythrocytes, hematocrit was positively correlated with hemoglobin and the number of erythrocytes. It is concluded that hemorrheological aspects should be considered when studying CVD among elderly people. 相似文献