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131.
A small but significant number of tritiated thymidine labelled cells were found, by autoradiography, in the glomeruli of rats with Masugi nephritis or chronic serum sickness nephritis. There were no labelled glomerular cells in sections of untreated animals. The findings favour the contention that in proliferative glomerulonephritis, glomerular hypercellularity is due to infiltration of monocytic cells into the tufts where they divide.  相似文献   
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The role of macrophages on the course of an infection with Toxoplasma gondii has been examined. Stimulation of macrophage function by killed Bordetella pertussis cells did not show any beneficial effect as an increased susceptibility became apparent. The functional blockade of macrophages by dextran sulfate or carbon particles did not result in a higher susceptibility of mice to the lethal primary infection with T. gondii. Thus in vivo macrophages apparently do not play an essential role as effector cells as they do in infections with other obligate intracellular infective organisms such as Listeria monocytogenes. The spleen is apparently of crucial importance for resistance against T. gondii infection, since death occurred earlier in splenectomized mice than in control animals.  相似文献   
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PURPOSE: Pelvic radiation is standard treatment for women with stage IIb to IVa cervical cancer, but treatment results are disappointing, particularly for women with bulky tumors. We investigated the role of primary chemotherapy followed by pelvic radiotherapy in a randomized trial. PATIENTS AND METHODS: Two hundred sixty patients with stage IIb and IVa cervical cancer received either standard pelvic radiotherapy or primary chemotherapy with cisplatin 60 mg/m2 and epirubicin 110 mg/m2 administered at 3-week intervals for three cycles, followed by pelvic radiotherapy. RESULTS: Ninety-nine patients have relapsed with a median follow-up duration of 1.3 years; in 62 patients, the first site of progressive disease was the pelvis. Patients who received primary chemotherapy had a significantly higher pelvic failure rate than those who received radiotherapy alone (P < .003). Seventy-six patients have died, and those who received primary chemotherapy had significantly inferior survival compared with those who received radiotherapy alone (P = .02). Tumor response following chemotherapy was observed in 63%. After radiotherapy, tumor response occurred in 72% of those who received combined modality treatment, compared with 92% of those who received radiotherapy alone. CONCLUSION: Primary chemotherapy with epirubicin and cisplatin, although resulting in tumor response in a significant proportion of patients, is accompanied by an inferior local control rate and survival compared with standard pelvic radiotherapy alone.  相似文献   
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半导体激光双稳运转中的相变   总被引:1,自引:0,他引:1  
张远程  宋骞  何绍伟 《中国激光》1992,19(9):682-686
利用Landau相变理论对光纤耦合输出反馈泵浦半导体激光双稳系统运转中的非平衡相变进行了理论分析。指出,反馈参量的增加是系统由二级相变向一级相变转化的条件。由此导出了系统三种工作模式及其用于光信号放大和处理的参数,与实验一致。  相似文献   
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Workers exposed to metallic mercury vapor were subjects for tremor, EMG, and psychomotor tests. Regression analysis revealed statistically significant trends in these test results related to workers' urine mercury histories. Effects were subclinical, functionally insignificant and most associated with those workers whose urine mercury had exceeded 0.5 mg/L in the previous year. In agreement with previous reports, effects were reversible upon reduction of mercury exposure.  相似文献   
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This article reviews the literature on the dreams of persons beyond 50 years of age. A reduced dream recall rate, if at all, does not appear to be the result of weakened memory capacities at that age, but may rather be due to a lower rate of current concerns. In a similar way, the changes in contents are not a function of aging per se, but have taken place already between the 20th and 45th year of age. The dreams of the dying can, because of the unusualness of the situation experienced by this group, be of a very particular nature and quality. At any age of life, the dream can become instrumental in healing processes. Dreams seem to be of vital importance in supportive psychotherapy after bereavement and, of course, during the process of dying.  相似文献   
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