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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   
3.
Alcohol consumption during pregnancy is teratogenic and induces severe alterations in hepatocytes. In the hepatocyte peroxisomal system, ethanol is converted in the presence of H2O2 to acetaldehyde and water. Therefore, peroxisomal catalase also acts as an antioxidant defence mechanism by removing H2O2 and preventing the formation of hydroxyl radicals in the cell. Alterations in peroxisomal catalase after pre- and pre+postnatal alcohol exposure were investigated in the rat. The effect of pre- and postnatal exposure to ethanol on hepatocyte subpopulations was analysed in isolated hepatocytes originating from periportal, intermediate and perivenous zones. Analysis of catalase revealed that the total activity and content of this enzyme were higher in 12-day-old cells than in cells from newborns and that this increment was more pronounced in treated cells. In controls, the amount of peroxisomal catalase increased mainly in periportal cells, whereas alcohol exposure induced a significant increase in the catalase of perivenous hepatocytes. We conclude that pre- and postnatal alcohol exposure mainly affects the perivenous hepatocyte peroxisomes and that the increase in peroxisomal catalase could constitute a defence mechanism against free radical generation induced by alcohol exposure during the perinatal period.  相似文献   
4.
We investigated the expression of intercellular adhesion molecule-1 (ICAM-1) and lymphocyte function-associated antigen-3 (LFA-3) by thyrocytes and their regulation by cytokines. Immunofluorescence studies on cryostat sections and on freshly dispersed cell preparations showed that ICAM-1 and LFA-3 are barely detectable in non-autoimmune thyrocytes. However, thyrocytes acquired ICAM-1 expression in culture. IFN-gamma, IL-1 beta and TNF-alpha produced a clear enhancement of ICAM-1 expression. When tested in combination, IL-1 beta and TNF-alpha were additive to the IFN-gamma effect. LFA-3 expression was not modulated by these cytokines. In the HT93 thyroid cell line generated by transfection with SV40, ICAM-1 and LFA-3 were both constitutively expressed at high levels. Cytokines modulated ICAM-1 expression similarly, but to a greater extent than in normal thyrocytes. LFA-3 remained unmodified. These results support the notion that normal thyrocytes are immunologically silent cells. The capability of cytokines to induce ICAM-1 together with HLA class I and class II-expression on thyrocytes suggests that under their influence, these cells may express all the surface molecules required for antigen presentation and/or for being recognized as target cells in the context of thyroid autoimmune disease.  相似文献   
5.
We evaluated the occurrence of REM sleep behaviour disorder (RBD) and vocal cord abductor paralysis (VCAP) in a group of 9 Machado-Joseph disease (MJD) patients. RBD was diagnosed by clinical history plus audiovisual polysomnography in 4 men and 1 woman (55%). While dreaming, 4 fell out of the bed and the other injured his arms. Laryngoscopy detected bilateral VCAP in 1 patient with stridor who required emergency tracheotomy, and partial vocal cord abductor restriction in 2. RBD and VCAP are two potentially injurious conditions that should be considered part of the clinical spectrum of MJD.  相似文献   
6.
Cholesterol embolism is a rare but serious complication of heart catheterization. We report a patient in whom cholesterol embolization syndrome developed after coronary angioplasty complicated by an acute myocardial infarction which was treated with streptokinase and heparin. The clinical outcome was satisfactory. Cholesterol embolism occurrence might have been precipitated in this patient by thrombolytic and anticoagulant therapy.  相似文献   
7.
The grumose degeneration observed in the dentate nuclei of 7 cases of progressive supranuclear palsy (PSP) was studied with a panel of antibodies which included 2 neurofilaments, Tau and ubiquitin. Dentate nucleus neurons were negative with all antibodies except ubiquitin which showed a slightly positive homogeneous pattern of staining. The amorphous material surrounding swollen or normal neurons was strongly positive for neurofilament and subunits and numerous torpedoes were observed in the granular layer of the cerebellar cortex. Our results confirm that grumose degeneration consists in degeneration of terminal axons of Purkinje cells in the dentate nucleus. The positivity of dentate nucleus neurons for ubiquitin may support the concept of synaptic dysfunction between Purkinje cells and dentate nucleus neurons.  相似文献   
8.
Wilson's disease (WD) is a rare liver-based disorder of copper metabolism. Prognostic criteria described by our group in 1986 to predict death without transplantation have not been universally validated. The clinical features of 88 children were reviewed, retrospectively in 74 and prospectively in 14. Data from the retrospectively recruited patients that died or survived on long-term chelation were used to evaluate the validity of our old scoring system and to devise a new prognostic index, then assessed in the 14 prospectively recruited patients. Using the old scoring system, 5 children scoring > or = 7, the cutoff value for death without transplantation, survived, whereas 4 scoring < or = 7 died (sensitivity 87% and specificity 90%). A new index based on serum bilirubin, international normalized ratio, aspartate aminotransferase (AST), and white cell count (WCC) at presentation identified a cutoff score of 11 for death and proved to be 93% sensitive and 98% specific, with a positive predictive value of 88%. When the new index was evaluated prospectively in 14 patients, it predicted the need for transplantation in only the 4 who required it, although 1 child with a score of 11 survived on medical treatment. In conclusion, the new Wilson Index is more sensitive and specific in predicting mortality without transplantation than the old scoring system, but needs to be validated in a larger number of patients.  相似文献   
9.
The diagnosis of idiopathic Parkinson's disease (PD) can be achieved with high degrees of accuracy in cases with full expression of classical clinical features. However, diagnostic uncertainty remains in early disease with subtle or ambiguous signs. Functional imaging has been suggested to increase the diagnostic yield in parkinsonian syndromes with uncertain clinical classification. Loss of striatal dopamine nerve terminal function, a hallmark of neurodegenerative Parkinsonism, is strongly related to decreases of dopamine transporter (DAT) density, which can be measured by single photon emission computed tomography (SPECT). The use of DAT‐SPECT facilitates the differential diagnosis in patients with isolated tremor symptoms not fulfilling PD or essential tremor criteria, drug‐induced, psychogenic and vascular Parkinsonism as well as dementia when associated with Parkinsonism. This review addresses the value of DAT‐SPECT in early differential diagnosis, and its potential as a screening tool for subjects at risk of developing PD as well as issues around the assessment of disease progression. © 2007 Movement Disorder Society  相似文献   
10.
Infections are a common complication of allogeneic bone marrow transplantation and the leading cause of transplantation-related mortality. It had been hypothesized that transplantation following nonmyeloablative preparative regimens would result in fewer infections by causing less mucosal injury, less graft-versus-host disease, and allowing earlier immune reconstitution. We have retrospectively reviewed the infectious complications of 65 consecutive patients with advanced hematologic malignancies who underwent bone marrow transplantation using a novel preparative regimen consisting of cyclophosphamide, thymic irradiation, and in vivo T-cell depletion. Cytomegalovirus (CMV) infection occurred in 52% of cases in which the donor or recipient had evidence of prior CMV exposure. Using a strategy of preemptive therapy and secondary prophylaxis with ganciclovir, no CMV disease occurred. Infections with gram-positive bacteria predominated over the first 100 days after bone marrow transplantation. Thereafter, the relative proportion of gram-negative infections increased without a significant increase in episodes of neutropenia. The rate of bacterial infections was not influenced by relapse of the underlying malignancy. Seven patients developed infections with Aspergillus species, which was the most common infectious cause of death in these patients. Infections with viruses other than CMV (n=10) and with protozoan organisms (n=2) also occurred. The use of HLA-mismatched donors, the occurrence of grade II-IV acute graft-versus-host disease, and treatment with corticosteroids did not influence the risk of CMV or bacterial or fungal infections in patients who underwent transplantation following this preparative regimen. Overall, the incidence and spectrum of infections in this series was similar to the reported incidence of infections following conventional myeloablative allogeneic stem cell transplantation. We conclude that a quantitative T-cell deficiency in these extensively T-cell depleted patients may be a risk factor for infection, even in the absence of graft-versus-host disease.  相似文献   
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