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81.

Introduction  

The assessment of adrenal function in critically ill patients is problematic, and there is evidence to suggest that measurement of tissue glucocorticoid activity may be more useful than estimation of plasma cortisol concentrations. Interstitial cortisol concentrations of cortisol represent the available pool of glucocorticoids able to enter the cell and bind to the glucocorticoid receptor. However the concentrations of plasma cortisol may not accurately reflect interstitial concentrations. We elected to perform a preliminary study into the feasibility of measuring interstitial cortisol by microdialysis, and to investigate the relationship between total plasma cortisol, free plasma cortisol and interstitial cortisol in patients with severe burns.  相似文献   
82.
PURPOSE: Eleven patients with progressive advanced malignancy after administration of a cancer vaccine received a fully human anti-CTLA-4 monoclonal antibody (ipilimumab). The primary end point was to determine drug toxicity. Tumor response, tumor-specific CD8+ T-cell immune responses, and modulation of CD4+ CD25+ FoxP3+ regulatory T-cell (Treg) numbers were secondary end points. EXPERIMENTAL DESIGN: Three patients with colon cancer, four with non-Hodgkin's lymphoma, and four with prostate cancer were treated. The first dose was given at 3 mg/kg and subsequent doses were administered monthly at 1.5 mg/kg for a total of four cycles. RESULTS: Tumor regression was observed in two patients with lymphoma; one of which obtained a partial response of 14-month duration. Ipilimumab was well tolerated with predominantly grade 1/2 toxicities. One drug-related grade 3 toxicity was observed. One patient died within 30 days of treatment due to progressive colon cancer. No increase in vaccine-specific T-cell responses was observed after therapy. Tregs as detected by expression of CD4+CD25+CD62L+ declined at early time points but rebounded to levels at or above baseline values at the time of the next infusion. CONCLUSIONS: Ipilimumab treatment depressed Treg numbers at early time points in the treatment cycle but was not accompanied by an increase in vaccine-specific CD8+ T-cell responses in these patients previously treated with a variety of investigational anticancer vaccines. A partial response was observed in one patient with follicular lymphoma. A phase I/II trial evaluating ipilimumab in patients with follicular lymphoma is currently ongoing.  相似文献   
83.
In this paper, we examine the problems associated with using quality adjusted life years (QALYs) as the measure of effectiveness to evaluate interventions for acute conditions. We illustrate the way in which using commonly accepted benchmarks for costs per QALY, in order to adopt interventions for acute conditions, might result in decisions that are not consistent with maximizing net societal benefit. We suggest that an alternate methodology, such as willingness to pay, may be more appropriate to make allocation decisions for acute conditions.  相似文献   
84.
OBJECTIVE: To investigate the pathogenesis of the systemic hemodynamic disturbance and the renal production of vasodilator prostaglandins (PGs) in the ovarian hyperstimulation syndrome. DESIGN: Prospective longitudinal study. SETTING: Assisted Reproduction Unit of the Hospital Clínic i Provincial in Barcelona. PATIENTS: Five in vitro fertilization patients with ascites because of severe ovarian hyperstimulation syndrome. MAIN OUTCOME MEASURES: Measurement during the syndrome and 4 weeks after recovery of the following: cardiac output, arterial pressure, estimated peripheral vascular resistances, hematocrit, standard renal function tests, plasma renin activity, plasma aldosterone, norepinephrine and antidiuretic hormone concentrations, and urinary excretion of PGE2 and 6-keto-PGF1 alpha. RESULTS: During the syndrome, all patients showed arterial hypotension (74.2 +/- 3.8 versus 85.8 +/- 1.0 mm Hg), tachycardia, increased cardiac output (6.4 +/- 0.2 versus 4.4 +/- 0.1 L/min), low peripheral vascular resistance (929 +/- 52 versus 1,568 +/- 51 dyn/sec per cm-5), high plasma levels of renin (72 +/- 25 versus 0.5 +/- 0.1 ng/mL per h-1), norepinephrine (639 +/- 141 versus 203 +/- 21 pg/mL) and antidiuretic hormone (6.1 +/- 1.6 versus 1.5 +/- 0.1 pg/mL), and increased urinary excretion of PGE2 (551 +/- 152 versus 106 +/- 44 pg/min) and 6-keto-PGF1 alpha (470 +/- 76 versus 99 +/- 11 pg/min). No evidence of hemoconcentration, as assessed by hematocrit, was observed in any patient. CONCLUSIONS: (1) Severe ovarian hyperstimulation syndrome is related to marked arteriolar vasodilation that leads to underfilling of the arterial vascular compartment and stimulation of endogenous vasoconstrictor systems and (2) the increased urinary excretion of PGs probably represents a homeostatic response to antagonize the renal effects of these systems.  相似文献   
85.
The present study is an attempt to estimate the albumin concentration in the human amniotic fluid of normal pregnancy. The study has been conducted from 12th to 20th week and from 30th to 43rd weeks of gestation. The results revealed a characteristic gestational profile with an increase in the concentration with the advancement of pregnancy from the 12th till the 20th week and an inverse relationship between the albumin level and the gestational age after the 30th week till term. The relationship between the albumin levels and the order of pregnancy indicated that the albumin concentration was not influenced by the birth order.  相似文献   
86.
87.
This article is a general view of acquired disorders of color vision. The revision of the best known methods and of the etiopathogenic classification is not very important in ophthalmology but on the other hand, the detection of the blue defect advertise and associated ocular pathology. There is a major interest in serious diseases as multiple sclerosis, AIDS, diabetes melitus, when the first ocular sign can be a defect in the color vision.  相似文献   
88.
1. The basal cytotoxic effect of the organochlorine pesticides hexachlorocyclohexane and lindane on CHO-K1 cultures was assessed at fractions of their lethal doses as determined by the neutral red incorporation (NRI) assay (NRI(6.25), NRI(12.5) and NRI(25)). The sulphur-redox cycle enzymes glutathione peroxidase, glutathione reductase and glutathione S-transferase, and total and oxidized glutathione were evaluated at several points during the standard growth curve of the cultures. 2. After incubation with each compound for 24 h, both glutathione peroxidase and reductase showed a substantial increase at the lowest exposure doses (NRI(6.25))--more significantly for lindane than for 1,2,3,4,5,6-hexachlorocyclohexane (HCH)--and dropped at higher doses of both compounds. The reduced and oxidized glutathione content was greatly diminished at the lower exposures, whereas the total glutathione content was higher at NRI(12.5) values. 3. Changes in cell membrane integrity were assessed for a wide range of pesticide concentrations with the lactate dehydrogenase release assay and lipid peroxidation. Membrane leakage and peroxide production were significantly enhanced at concentrations of HCH 50 microg ml(-1), although this effect was not significant at lindane concentrations < 200 microg ml(-1). 4. Lipid peroxidation increased with exposure to HCH at concentrations as low as NRI(6.25), whereas in the case of lindane, this increase was only significant at doses of NRI(25) and above.  相似文献   
89.
Intracranial hemorrhage is an uncommon complication of phenylpropanolamine. There is an increasing awareness of this complication in the West. However, to the best of our knowledge there have been no cases reported from India. Here we report a patient who developed Intraventricular hemorrhage following ingestion of Phenylpropanolamine, from which he made an uneventul recovery over the next two weeks.  相似文献   
90.
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