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61.
We report two cases of idiopathic intracranial hypertension in patients with Graves' ophthalmopathy. These patients, with known Graves' ophthalmopathy, presented with new onset optic disc edema and preserved visual function. Moderate enlargement of the extraocular muscles was observed in one case and moderate expansion of the orbital fat volume was observed in the second case. Lumbar puncture revealed an elevated opening pressure and normal cerebrospinal fluid composition in both patients. Also, no intracranial abnormalities were seen with neuroimaging studies. The findings in these patients suggest idiopathic intracranial hypertension as a second concurrent diagnosis, and should be considered as a possible etiology of optic disc edema in patients with Gravest ophthalmopathy and preserved visual function.  相似文献   
62.
The effectiveness of an antiarrhythmic drug is judged by the degree of ventricular arrhythmia (VA) suppression. We evaluated the relationship between the degree of VA suppression and survival in a dose-adjusted trial of 110 symptomatic patients treated with amiodarone. Cohorts had left-ventricular ejection fraction (LVEF) of 41 plus minus 18%, ventricular premature contractions (VPCs) of 445 plus minus 571 h, couplets (C) of 733 plus minus 1498 24 h and nonsustained (N) ventricular tachycardia (VT) of 65 plus minus 217 24 h; these conditions were followed for 15 plus minus 11.5 months. Amiodarone was initiated with an oral loading of 670 plus minus 111.7 mg per day for 10 days and continued on maintenance of 274.9 plus minus 102 mg per day. Survival rates of responders and nonresponders with VPCs <70%, 70--89%, greater-than-or-equal90%; C greater-than-or-equal 90%; NVT (100%); and the response to all 3 criteria (suppresion of VPCs greater-than-or-equal70%, C greater-than-or-equal 90% and complete abolition of NVT) were not statistically significant. Survival rates as a function of LVEF <40% (51 patients) or greater-than-or-equal40% (59 patients), as well as responders or nonresponders to all three criteria, were not significant (p = NS). We conclude that, in patients treated with low-dose amiodarone, the degree of VA suppression of PVCs, C and NVT does not predict survival; the survival of patients with LVEF <40% improved irrespective of VA suppression; and criteria for VA suppression should be reassessed at lower levels of suppression for the improvement of the drug risk:benefit ratio. More improvement is not necessarily better.  相似文献   
63.
64.
A dihydropyridine pyridinium salt redox carrier-based chemical delivery system for benzylpenicillin (1) was complexed with 2-hydroxypropyl--cyclodextrin (HPCD). The solubility of the lipophilic 1, which is incompatible with aqueous formulations, was dramatically increased and showed a linear dependency on the HPCD concentration. The degree of incorporation was 20 mg of 1 per g of complex. The stability study of 1 in various pH buffers indicated the base-catalyzed hydrolysis of the acyloxyalkyl linkage and the hydration of the 5,6 double bond of the dihydropyridine as the main degradation processes. The overall loss of 1, which follows first-order kinetics, was not influenced by changes in ionic strength and elimination of oxygen from the reaction medium. The HPCD complex of 1, which has a stability constant of 720–940 M –1, stabilized the chemical delivery system. The influence of the temperature on the stability of 1 is also discussed.  相似文献   
65.
This study explored the relationship between adenine nucleotide levels in canine renal cortex and renal function following: (a) graded periods of warm ischemia; (b) 48 hours' flush cooling with electrolyte solutions and ice storage; and (c) continuous hypothermic perfusion. Exposure to normothermic ischemia resulted in a rapid (within 15 minutes) degradation of ATP to ADP and AMP as well as a slow decline in total adenine nucleotide (TAN) to levels which were proportional to the duration of the ischemic injury. No functional impairment was evident after 15 minutes' ischemia, but with longer times, both the extent of decline in TAN and the degree of recovery following restoration of blood flow could be used to predict the quality of renal function.The relationship between TAN levels and function was of less predictive value following cold storage or continuous perfusion. The efficacy of intracellular flush solutions could not be attributed solely to conservation of TAN, nor did the well-maintained TAN levels during continuous perfusion necessarily lead to significantly better 48-hour storage than flush cooling with C2 solution.
Résumé Cette étude faite chez le chien examine la corrélation entre la fonction rénale et le taux d'adénine nucléotide dans le cortex rénal suite à: 1) différentes périodes d'ischémic chaude; 2) entreposage sur glace pendant 48 heures apres flushing avec des solutions électrolytiques; 3) hypotermie par perfusion continuelle. L'ischémie chaude a produit une dégradation rapide de l'ATD en ADP et AMP (en moins de 15 minutes) et une diminution progressive de la quantité totale d'adénine nucléotide (TAN) proportioneile à la durée de la période ischémique. La fonction rénale n'a pas été affectée par des périodes d'ischémie de 15 minutes ou moins. Suite à des périodes ischémiques plus longues cependant, la chutte des taux de TAN et leur niveau de rétablissement après réouverture de la circulation sanguine ont permis de prédire la qualité de la fonction rénale. Après storage au froid ou perfusion continue, la relation entre les taux de TAN et la fonction rénale est disparue. Le flushing à l'aide des solutions de type intracellulaire, malgré sa faible capacité à conserver les taux de TAN s'est avéré une méthode d'entreposage aussi efficace que la perfusion continuelle, laquelle a maintenu des taux normaux de TAN.


Supported by Veterans Administration Research Grant 1519-01.  相似文献   
66.
PURPOSE: Macrophage inhibitory cytokine-1 (MIC-1) is a divergent member of the tumor growth factor beta (TGF-beta) superfamily. Several observations suggest that it plays a role in colorectal carcinoma (CRC). In particular, MIC-1 is markedly up-regulated in colorectal cancers as well as in premalignant adenomas. This study examines the relationship of serum MIC-1 levels and genotypes to clinical and pathologic features of colonic neoplasia. Experimental Design: We confirmed the presence of MIC-1 in CRC tissue and the cell line CaCo-2. The normal range for serum MIC-1 levels was defined in 260 healthy blood donors, and the differences between normal subjects and 193 patients having adenomatous polyps or CRC were then determined. In a separate cohort of 224 patients, we evaluated the relationship of MIC-1 serum level and genotype to standard tumor parameters and outcome measures. RESULTS: MIC-1 was expressed in CRC tissue and the cancer cell line CaCo-2. There was a progressive increase in serum MIC-1 levels between normal individuals [mean (M) = 495 pg/ml, SD = 210), those with adenomatous polyps (M = 681 pg/ml, SD = 410), and those with CRC (M = 783 pg/ml, SD = 491)]. Serum MIC-1 level was correlated with the extent of disease so that the levels were higher in patients with higher Tumor-Node-Metastasis stage. There were significant differences in time to relapse and overall survival between subjects with different MIC-1 levels and genotypes. CONCLUSIONS: This study identifies a strong association between MIC-1 serum levels and neoplastic progression within the large bowel. We suggest that the measurement of serum MIC-1 levels and determination of MIC-1 genotype may have clinical use in the management of patients with CRC.  相似文献   
67.
The Human Genome Project will have an enormous impact on our ability to study and understand human disease by providing maps of human genes. However, many of the most prevalent human diseases result from the complex interaction of numerous genes. Even with the use of a catalogue of human genes, the task of analyzing complex genetic and environmental interactions involved in the common human disorders will be formidable. Due to its demographic specificities and large size, the Chinese population offers a unique resource for the study of human genetics and the ability to capitalize upon the recent revolution in biotechnology. Reasons that China provides an exceptional population for genetic studies of complex diseases include: (i) the resource of 1.3 billion people makes obtaining a large number of subjects with rare (and common) diseases possible; (ii) relative genetic homogeneity in many regions has been preserved; (iii) stratification is distinct; (iv) urban/rural and geograph ic contrasts, both in environmental factors and disease occurrence, are quite marked; (v) family members tend to stay congregated; and (vi) epidemiologic study is cost-beneficial.  相似文献   
68.
69.
PURPOSE: To determine the incidence of second malignancies among patients with Hodgkin's lymphoma (HL) treated with autologous hematopoietic stem cell transplantation (AHSCT) compared with patients receiving conventional therapy alone and to identify potential risk factors for their occurrence. PATIENTS AND METHODS: We analyzed data on 1,732 consecutive patients with HL treated at the British Columbia Cancer Agency from 1976 to 2001, including 202 patients undergoing AHSCT. The median follow-up duration was 9.8 years for the whole cohort, 9.7 years for those patients treated with conventional therapy, and 7.8 years from AHSCT. RESULTS: The cumulative incidence of developing any second malignancy 15 years after therapy for HL was 9% (risk ratio = 3.5; P < .001); however, the incidence did not differ between those patients receiving conventional therapy alone compared with those undergoing AHSCT (10% and 8%, respectively; P = .48). In multivariate analysis, the only factor significantly associated with an increased risk of developing any second neoplasm or solid tumor was age > or = 35 years (P < .0001). An increased risk of therapy-induced acute myeloid leukemia and therapy-induced myelodysplastic syndrome was seen for patients aged > or = 35 years (P = .03) and stage III/IV (P = .04). CONCLUSION: Patients with HL are at increased risk of developing a second neoplasm. However, those patients undergoing AHSCT do not seem to be at greater risk compared with those patients receiving conventional therapy alone, at least during the first decade after therapy.  相似文献   
70.
PURPOSE: Ifosfamide, carboplatin, etoposide, and vincristine, alone and in combination, are highly active against small-cell lung cancer (SCLC). This trial was designed to investigate whether survival could be improved by a regimen of all four drugs (ICE-V) compared with standard chemotherapy in patients with SCLC and good performance status, and to assess the patients' quality of life (QL). PATIENTS AND METHODS: Patients were randomly assigned to receive six cycles of either ICE-V at 4-week intervals without dose reduction or standard chemotherapy administered according to local practice. The recommended standard control regimens were cyclophosphamide, doxorubicin, and etoposide; and cisplatin and etoposide. RESULTS: A total of 402 patients were randomly assigned, and 350 (87%) patients have died. Overall survival was longer in the ICE-V group (hazard ratio, 0.74; 95% CI, 0.60 to 0.91; P = .0049), median survival was 15.6 months in the ICE-V group and 11.6 months in the control group, and 2-year survival rates were 20% and 11%, respectively. There was no evidence that the relative survival benefit for ICE-V was less in extensive-stage than in limited-stage patients. An increased rate of septicemia was reported in the ICE-V group (15% v 7% in the control group), but this did not result in an increase in reported treatment-related deaths (four patients [2%] in both groups). The findings on QL were broadly similar in both groups, with some benefit in favor of ICE-V. CONCLUSION: Compared with standard chemotherapy, the ICE-V regimen improves overall survival without QL penalties, despite an increased but manageable level of toxicity.  相似文献   
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