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941.
A case of cryptococcal meningoencephalitis, as presented by a hypertensive hydrocephalus, is described. To our knowledge, this is the 24th case described in Italy since 1953. The diagnosis was made with ventricular fluid examination: the patient was successfully treated with amphotericin B and 5-fluorocytosine, thus avoiding the risks of surgical treatment of hydrocephalus. Early diagnosis and proper therapy are necessary in order to decrease the high lethality of cryptococcosis.  相似文献   
942.
Osteomalacia and bone disease arising from aluminum   总被引:2,自引:0,他引:2  
  相似文献   
943.
Immersion of rat hemidiaphragms in Ca2+-free Krebs solution (KS) containing Ca2+ chelator in vitro leads to separation of basal lamina from the plasma membrane, as well as transient contracture and rapid loss of twitch response [calcium paradox (CP) phase 1]. Subsequent immersion in regular KS results in necrosis of muscle fibers accompanied by slowly increasing contracture (CP phase 2). This contracture could be prevented or reduced by using either Ca2+-free KS or calcium channel blockers, but not by dantrolene sodium, implying that after drastic reduction of extracellular and sarcolemmal Ca2+ during CP phase 1, the sarcolemma has lost its ability to control normal Ca2+ fluxes. Contracture did not develop at 21 degrees C. CP is a convenient model to study calcium-induced muscle cell death and the role of Ca2+ in maintaining sarcolemmal integrity.  相似文献   
944.
Estimating the economic costs of a disease is an important prerequisite to determining the costs and benefits of various preventive programs. For preventive programs, incidence-based costing is a more appropriate means of estimation than is prevalence-based costing. In this study the cost of acute myocardial infarction (AMI) in New South Wales has been estimated using an incidence-based approach. The calculated cost of AMI in 1979 was $301.0 million, made up of $32.3 million as direct costs and $268.7 million as indirect costs. In a sensitivity analysis, the cost was shown to be most sensitive to the incidence of AMI, the discount rate, and the assumption of a wage for housework. Both the direct costs and indirect costs per case are substantially higher in the United States than in Australia, and this reflects higher physician charges, higher hospital costs, and in the case of indirect costs, higher average weekly earnings.  相似文献   
945.
In brain regions containing noradrenergic (NA) cell bodies or terminals, DSP-4 induces changes in the activity of catecholamine-synthesizing enzymes which suggest that central NA neurons are lesioned by this neurotoxin. In contrast, the lack of change in the same enzymatic activities in an area containing mostly adrenergic (A) neurons (C2 region), favors the hypothesis of a resistance of the A neurons to DSP-4. Furthermore, the enzymatic changes observed in peripheral organs suggest a peripheral activation of the NA cell bodies in response to lesioning of the sympathetic terminals by DSP-4.  相似文献   
946.
947.
948.
T-514 (Peroxisomicine A(1)) from Karwinskia humboldtiana is a dimeric hydroxyanthracenone with a highly selective cytotoxic effect on tumor cells. We evaluated the metabolism of this compound in two in vitro systems (liver microsomes and hepatocytes) and assessed the cytotoxicity of its metabolites on normal and tumor cells. Microsomes (12.5, 125 and 250 microg of protein/ml) and hepatocytes (1 x 10(6) cells/ml) were incubated with the toxin (25 microM) for 0.5, 1, 3, 6, 9, 12 and 24 h and the samples were examined using chromatographic analysis and UV spectra. Two metabolites (M1 and M2) were detected in the rat microsomes and one (M1) in the monkey microsomes. The retention times and UV spectra of the peaks were very similar to those of the toxin T-514. M1 was isolated and identified as a mixture of two isomers. The cytotoxicity of the metabolites was evaluated in Chang liver and Hep G2 cells but they did not show the selective cytotoxic effect on tumor cells seen in the original compound.  相似文献   
949.
PURPOSE: The use of gefitinib, the first drug approved to inhibit the epidermal growth factor receptor tyrosine kinase, is indicated in patients with non-small-cell lung cancer with tumors progressive after chemotherapy. The unique mechanism of action of this agent leads to distinctive patterns of response and toxicity in persons with lung cancer. Many of the principles of management relevant to gefitinib are distinct from those with conventional cytotoxic drugs. To meet this need, we present practical guidelines on the use of gefitinib in patients with non-small-cell lung cancer. METHODS: This article reviews gefitinib's indications, dosing, response phenomena, and patterns of relapse in individuals with radiographic response. RESULTS: We present our recommendations for the management of rash and diarrhea caused by this agent. CONCLUSION: This information can guide practitioners and help them inform their patients about what to expect when they receive gefitinib.  相似文献   
950.
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