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891.
A model of pulmonary blastomycosis in the mouse, in which the portal of entry is the same as natural human infection, was used to study resistance to challenge after subcutaneous infection. One week after subcutaneous infection, mice were partially resistant to pulmonary challenge, and mice challenged two weeks after infection were resistant. Measurement of cellular and humoral immune responses to Blastomyces dermatitidis antigens after subcutaneous infection showed the following. (i) Delayed-type hypersensitivity appeared 1 week after infection, and responses increased for 3 weeks thereafter. (ii) Proliferative responses in vitro appeared in spleen cells at 1 week and in contralateral lymph node cells at 3 weeks, (iii) Serum antibody, detected by an enzyme-linked immunosorbent assay, appeared 1 week after infection and then increased in titer. (iv) Peritoneal macrophages were activated to inhibit replication of B. dermatitidis in vitro by the first week after infection. Prior subcutaneous infection also resulted in rapid clearing of a second subcutaneous challenge, as well as resistance to a lethal intraperitoneal challenge. This resistance was associated with the development of cell-mediated and humoral immune responses. These data provide a chronological framework for selective transfer experiments. 相似文献
892.
DA Sarti 《Canadian Metallurgical Quarterly》1977,125(3):789-793
Three cases of pancreatic pseudocyst were followed serially by ultrasound examination. The entity was found to be more dynamic than has been generally thought. The rapid development and spontaneous regression of pancreatic pseudocysts was documented. The timing of surgical intervention in these cases must be reevaluated. 相似文献
893.
894.
VH Denenberg M Hofmann JA Garbanati GF Sherman GD Rosen DA Yutzey 《Canadian Metallurgical Quarterly》1980,200(1):123-133
Rats were handled for the first 20 days of life or were not disturbed. When adults, they were trained to approach and drink from a bottle containing sweetened milk and were then given an injection of lithium chloride to induce a taste aversion conditioned emotional response. Others were injected with physiological saline. Rats within each of the treatment groups were then randomly assigned to 4 surgical procedures: removal of the right or left neocortex; sham surgery; or no surgery. Postoperatively, they were tested for retention of taste aversion by presenting the sweetened milk and recording the amount consumed. The initial consummatory behavior was very low (showing retention of the aversion) and increased over time. There were no differences in the reacquisition curves of the non-handled groups which had received lithium chloride. The curves of the handled groups did differ: thos with an intact right hemisphere (left neocortical lesion) had the lowest asymptote, followed by the group with an intact left brain, while those with intact whole brains consumed the greatest amount of milk. In the groups given an injection of physiological saline, those with a left hemisphere lesion consumed less milk than the other groups, regardless of their early handling experience. The data show: (1) that the rat's brain is lateralized, with the right hemisphere being preferentially involved in conditioned emotional behavior; and (2) that handling in infancy makes the left hemisphere less suceptible to conditioned fear. 相似文献
895.
896.
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898.
Plasma fibrinogen and white blood cell count were compared in fifty patients aged 25-50 years with periodontal disease and in fifty age-matched controls with relatively healthy periodontal tissues. Patients had significantly higher levels of fibrinogen and white cell count, and dental indices correlated significantly with these two cardiovascular risk factors on multivariate analyses. We suggest that inflammatory dental disease may be a determinant of fibrinogen level and white cell count in the general population, and that fibrinogen and white cell count may be two mediators of the link between dental disease and myocardial infarction. 相似文献
899.
DA Parsons B Lawhorn MA Walker JF Edwards BA Hague 《Canadian Metallurgical Quarterly》1998,212(2):262-264
A sporadic case of trilateral retinoblastoma in a male child of 20 months is described using clinical and imaging approaches. Attempts were made to find out a tumour marker by analysing human chorionic gonadotrophin (hCG), alpha-feto protein (AFP), carcinoembryonic antigen (CEA), and lactic dehydrogenase (LDH) in blood and cerebrospinal fluid (CSF). Only LDH was elevated in CSF and the rest were normal. Retinoblastoma gene could not be isolated in this patient. It is proposed that LDH in CSF should be analysed in patients with bilateral retinoblastoma who had normal brain scan initially. If LDH level in CSF is elevated, the patient should be periodically monitored by non-invasive imaging of the brain to detect intracranial tumour at an early stage. 相似文献
900.
A growing group of institutions and individuals use Internet connections to reach information sources. Large health care organizations now see electronic records as essential to providing cost-effective health care. The Visible Human Project represents the entire three-dimensional anatomy of a cadaver. 相似文献