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821.
Ten cases of primary subacute osteomyelitis illustrate its clinical resemblance to various bone neoplasms. Diagnosis was established by open biopsy. Treatment with curettage, cast immobilization, and antibiotics, when indicated, resulted in radiographic healing and resolution of symptoms.  相似文献   
822.
823.
The serum immunoglobulin levels of 200 first-degree relatives and 23 spouses of 32 patients with myelomatosis were compared with those of age- and sex-matched control persons. First-degree relatives of myeloma patients appeared to have higher serum levels of IgG (P less than 0.05), IgA (P less than 0.05), and IgM (P less than 0.01) than their age- and sex-matched controls. The spouses as a group did not differ from their controls in this respect. No statistically significant difference in the incidence of M-components among family members (0.6%) and spouses (4.3%) was found compared with the incidence in the general population (0.9%). Myelomatosis as such appeared to be more frequent than in the general population (P less than 0.05).  相似文献   
824.
The retinex theory of color vision   总被引:8,自引:0,他引:8  
  相似文献   
825.
The mortality from coronary heart disease (CHD) in Norway increased rapidly during 1951-70, the highest mortality rates as well as the most rapid increases being found in Northern Norway. Several surveys of CHD were then planned, one of them is reported here. All men, 20-49 years of age, living in the municipality of Troms?o, Troms county, were called up for examination. In total, 6595 men, 74.4% of those invited, were examined. Cholesterol, triglyceride and Hb values, BP, body weight and height, the percentage of smokers, and cigarette consumption have been tabulated according to area, age, work schedule, health condition, physical activity and ethnic background. The results suggest that the relatively high mortality from CHD in Northern Norway is associated with high serum cholesterol concentrations as well as a relatively high prevalence of smoking. During the screening there were indications of changes in dietary habits in the municipality, presumably as a result of accompanying publicity.  相似文献   
826.
Lethal gas embolism always occurs after FC 80 liquid fluorocarbon is injected intravenously (0.1 ml/kg body mass) in dogs breathing room air but not in dogs breathing oxygenated FC 80 liquid fluorocarbon. Gas embolism is not prevented in dogs that have been injected intravenously with FC 80 when they are exposed to 2 ATA (atmospheres absolute) 20% 02-80% N2, 9 ATA 5% O2-95% He, or 1 ATA 100%, O2. In dogs that die of FC 80-induced gas embolism, free gas in the right atrium contains approximately 0.5 g FC 80/liter, and Po2 and Pco2 in the gas are in equilibrium with their corresponding tensions in right atrial blood. These observations are consistent with the hypothesis that PFC 80 in alveolar gas does not equilibrate with PFC 80 (55 mmHg) in blood. The total gas tension in pulmonary capillary blood containing FC 80 and its vapor thus exceeds the total tension of alveolar gases (atmospheric pressure). Bubbles of O2, CO2, N2, FC 80, and water vapor form in the regions of the pulmonary capillary bed where the total tension of gases dissolved in blood exceeds the absolute blood pressure.  相似文献   
827.
828.
Neuromuscular junction ultrastructure in rat forelimb digit extensor muscle was sequentially and quantitatively investigated in experimental autoimmune myasthenia gravis (EAMG). Experimental animals were immunized with highly purified eel electroplax acetylcholine receptor protein plus complete Freund's adjuvant and B pertussis vaccine; control animals received only adjuvant and vaccine. During the first 7 days (latent period) after immunization end-plate structure and neuromuscular transmission remained normal in the experimental group. Between day 7 and 11 (acute phase) mononuclear cells infiltrated those regions of muscle where the end-plates were located and there was intense degeneration of the postsynaptic regions with splitting away of abnormal junctional folds from the underlying muscle fibers. Macrophages entered the gaps thus formed and removed the degenerating folds by phagocytosis. The nerve terminals were displaced from their usual location but maintained their structural integrity. Neuromuscular transmission was blocked in many muscle fibers. Miniature end-plate potentias (MEPPs), detectable in only a few fibers, were of abnormally low amplitude. After day 11 (chronic phase) the nerve terminals returned to the highly simplified postsynaptic folds became reconstituted and again degenerated. Immature junctions with poorly differentiated postsynaptic regions and nerve sprouts near end-plates were also observed. In two animals relapsing during the chronic phase degeneration of the postsynaptic folds was more intense than in the other chronic-phase animals. The posysynaptic membrane length and length per unit area and the MEPP amplitudes were significantly decreased in all chronic phase animals and the decreases were greater in the relapsing than in the non-lapsing animals. Minor morphometric alterations were also observed in the nerve terminals. These might have been secondary to the postsynaptic changes. The postsynaptic region is the primary target of the autoimmune reaction in EAMG. The ultrastructural, morphometric and electrophysiological abnormalities of the end-plate in chronic EAMG resemble those which have been observed in human myasthenia gravis.  相似文献   
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