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Parental AKR/J, and AKB6F1 and AKD2F1 hybrid mice were injected subcutaneously with a spontaneously arising AKR/J tumor. The highly responsive AKB6F1 strain never exhibited any depression of immune functioning during the course of tumor growth and regression. The (AKR/J) intermediately responsive strain, while able to generate a successful anti-tumor response, did display a transient reduction of immunological capability, but only during the period tumor growth and not during tumor regression. Cells able to suppress antibody, but not cell-mediated responses, were found. The unresponsive AKD2F1 strain was characterized by both a marked depression of immune responsiveness, as well as the generation of suppressor cells to both antibody, and later, cell-mediated responses. Depression of immune responsiveness, and the generation of suppressor cells, appeared to correlate with the strength or weakness of the anti-tumor response in these strains of mice. 相似文献
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916.
Influenza C was propagated by serial undiluted passage; conditions known to produce non-infectious (von Magnus) particles with influenza A and B. Following each passage infectious material was assayed for infectivity and haemagglutinating activity and the values related by calculating the log difference between infectivity and haemagglutinating titre (I:A ratio). Infectious material from each pass was examined for ultrastruct aberrations by negative strain electron microscopy. Influenza C exhibited a significantly smaller decrease in I:A ratio than exhibiyed by similarly propagated influenza A and B. Ultrastructural examination of the serially passed influenza C revealed no production of morphologically aberrant forms, whereas serially passed influenza B produced a strikingly altered morphology. 相似文献
917.
150 human arterial segments of high or low susceptibility to develop atheromas were studied for differences in the amount of histochemically demonstrable acid esterase in them. An inverse relationship was found between intimal or medial enzyme content and susceptibility to atheroma formation. 相似文献
918.
We reviewed 179 patients who had undergone thoracotomy and resection of a suspected malignant coin lesion of the lung over the past 20 years to see if a policy of early thoracotomy was therapeutically valid. The average diameter of all lesions was 1.6 cm; the average diameter of 27 malignant lesions (15 percent) was 1.8 cm. Follow-up of the 27 patients with malignant neoplasms was 100 percent. The present survival rate of the 19 patients with primary lung cancer is 89 percent (17/19). Of 12 cases of primary lung cancer followed for five years, ten (83 percent) survived. The five-year survival of the eight patients with metastatic lesions was 25 percent (2/8). There were no postoperative deaths and few serious postoperative complications (four patients or 2 percent). Very small primary lung cancers detected and treated early do have the same poor prognosis as larger primary cancers. 相似文献
919.
GM Peavy S Silverman EB Howard RS Cooper LJ Rich GN Thomas 《Canadian Metallurgical Quarterly》1976,169(9):915-919
An adult, female sulfur-crested cockatoo (Kakatoe sp) was examined because of dyspnea associated with hemoptysis. On radiographic examination there was a large cystic pulmonary mass that, on aspiration, was found to contain thick sanguineous fluid. Ziehl-Neelsen staining of aspirate smears revealed numerous acid-fast organisms. Gross necropsy and microscopic findings suggested a diagnosis of tuberculosis, with primary focus of infection in the pulmonary tissues. Bacteriologic isolation and typing confirmed a diagnosis of tuberculosis and established Mycobacterium avium as the etiologic agent. 相似文献
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