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991.
Summary Squamous cell carcinoma of the head and neck is a disease predominantly of males and is due to a variety of known environmental irritants, notably cigarette smoke. Dietary, viral and immunological factors may also be relevant. Head and neck squamous cancers express epidermal growth factor receptors and some show weak levels of oestrogen receptor activity, but a reliable serum marker of tumour burden remains to be identified. The prognosis is found to be less favourable in females, in those with advanced T stage, in association with multiple node involvement, especially where extracapsular spread is present and where the T4/T8 ratio is elevated. Administration of heterologous blood during therapy may also have an adverse effect on prognosis. Interested clinicians must remember that most cases are preventable. Correspondence to: A.G.D. Maran  相似文献   
992.
Cultured keratinocytes were used as allografts on burn wounds in two patients. In both patients successful covering of the wounds was obtained. DNA fingerprinting of the epidermis covering the wounds 21 days later showed that the cultured keratinocytes were replaced by the patients' cells.  相似文献   
993.
To investigate the role of cell-mediated immunity (CMI) in glomerulonephritis (GN), we identified the infiltrating immune cells both within the glomerulus and in the interstitium. Frozen sections from 103 patients with various forms of GN: 10 with minor glomerular abnormality (MGA) as control, 10 with minimal change nephrotic syndrome (MCNS), 10 with membranous nephropathy (MN), 9 with focal glomerulosclerosis (FGS), 30 with IgA nephropathy (IgAN), 22 with acute post streptococcal glomerulonephritis (APSGN), and 2 with rapidly progressive glomerulonephritis (RPGN) were examined using monoclonal antibodies (MoAb) by indirect immunoalkaline-phosphatase labelling. In most glomerulonephritis, monocyte/M phi and helper/inducer T cells were predominantly infiltrating in the interstitium, but intraglomerular infiltration was rare, except for APSGN. This interstitial infiltration increased proportionally to the level of serum creatinine, and was most prominent in RPGN. Apparently different distribution was seen in APSGN, that is, prominent increase in total number of intra-glomerular monocyte/M phi infiltration with slightly increased T cells. The change was correlated with time after onset; namely the more leucocytic infiltration was observed when the tissue was taken earlier. These data suggest that in APSGN, monocyte/M phi accumulate in glomeruli via cell mediated immunity in addition to humoral immune mechanism resulting in glomerular hypercellularity, whereas in most chronic glomerulonephritis interstitial leucocyte infiltration, particularly helper T cells and monocyte/M phi may play an important role in the progression of glomerulonephritis.  相似文献   
994.
We have presented a rare case of primary involvement of the anterior mediastinum by osteogenic sarcoma in which CT was useful in demonstrating calcium within the mass, and in distinguishing the mass from surrounding bony structures. Although rare, extraosseous osteogenic sarcoma should be included in the differential diagnosis of a calcified anterior mediastinal mass.  相似文献   
995.
Six patients with pregnancies of 19-31 weeks' duration showing evidence of erythroblastosis fetalis were treated with 25 fetal intracardiac blood transfusions. Complications related to the procedure occurred on five occasions in three patients. In two of the six patients the fetus died, but it was unlikely that death was related to the intracardiac transfusions. Fetal intracardiac blood transfusion may result in potentially severe complications but offers an alternative when transfusion cannot be performed into the umbilical cord.  相似文献   
996.
The effects of physiological and pathological concentrations of glucocorticoids were investigated using the glucocorticoid antagonist RU486 and the synthetic glucocorticoid dexamethasone, respectively. The effects of these treatments on the concentrations of glutamine and other amino acids in skeletal muscle and plasma and on the rates of release of glutamine and alanine from incubated preparations of skeletal muscle of the rat were investigated. Dexamethasone treatment increased the concentration of glutamine and the rate of release of this amino acid from incubated soleus muscle preparations. This treatment decreased the concentration of glutamine in both gastrocnemius and EDL muscles, but was without effect on the rate of glutamine release from EDL muscles. In contrast, administration of the glucocorticoid antagonist RU486 decreased the rate of glutamine release from muscle. It is concluded that glucocorticoids have marked effects on the metabolism of glutamine by skeletal muscle per se and that these hormones may be important in the control of the rate of glutamine release from muscle in both physiological and pathological conditions.  相似文献   
997.
The present authors investigated the excretion, distribution and pharmacokinetics of the novel potential antirheumatic agent flobufen and its active metabolite after p.o. and i.v. doses of 2, 10 and 50 mg/kg administered to rats. The drug is resorbed well from the digestive tract and mostly it is metabolized to the principal metabolite M, which is only slowly excreted from the organism mainly by renal clearance. Within the whole dose range the kinetics of the drug is linear. Binding of flobufen and M to proteins is high (95-99%). The highest concentrations of radioactive metabolites (mostly M) were found in the plasma, liver, lungs, kidneys, connective tissue and inflammatory foci. The penetration of metabolites through the placenta and excretion in human milk are relatively important.  相似文献   
998.
999.
PCP and related compounds inhibit 3H-mazindol binding to the cocaine receptor on dopamine transporters. The relative potencies of these compounds are such that some of the behavioral effects of PCP could be related to its action at the cocaine receptor; however, the affinity of PCP at the cocaine site (Ki = 1.59 microM) is less than its affinity at its own receptor (Ki about 0.12 microM). More data will be needed to conclusively implicate the cocaine receptor in the action of PCP.  相似文献   
1000.
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