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61.
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Biomarkers have long held out the promise that malignancies might be diagnosed early and that patients could be monitored more confidently during their clinical course to more reliably predict recurrence and the effect of therapy. Reliable tumor markers have been described for colon carcinoma, hepatomas, and other tumors, but no reliable marker has been identified to monitor the course of malignant melanoma. Recently, the plasma level of lipid-bound sialic acid (LASA-P) has been described as reflecting an alteration in the surface membrane of cancer cells. An attempt was made to correlate the LASA-P level, along with the serum level of neuron-specific enolase, a glycolytic enzyme specific to cells of neuroectoderm origin including melanocytes, with clinical disease activity with a follow-up to at least 2 years. Two hundred seventy patients had blood samples drawn at various times during their clinical course for assay of LASA-P and neuron-specific enolase. Eighty of the patients (30%) sampled developed a recurrence sometime during their clinical course, whereas another 10 patients had active disease noted at diagnosis with evaluative tumor markers. The sensitivity and specificity of neuron-specific enolase was 27% and 77%, respectively, and cannot be recommended as a marker for melanoma. LASA-P showed a sensitivity of 65%, with 55 patients recurring and having active disease with abnormally high markers and 35 patients recurring or having active disease with normal markers. Specificity of the LASA-P test was 76%. When recurrence was associated with elevated LASA-P levels, the elevated level preceded recurrence by a median of 9.3 months. LASA-P may be a useful marker to follow patients with malignant melanoma. 相似文献
63.
The potential value of retroviral gene transfer as a means of targeting therapeutic genes to neoplastic cells is threatened by the tendency of occasional cells to lose transduced genes or their expression. To determine whether this threat could be reduced by transducing multiple copies of a therapeutic gene, we compared 8 murine sarcoma sublines carrying from 1 to 6 copies of a retrovirally transduced herpes simplex virus thymidine kinase gene, which sensitizes cells to ganciclovir (GCV). When variability consequent to differences in vector integration site was excluded, increased copy number was associated with an increase in GCV sensitivity and a major reduction in the frequency of GCV-resistant mutants. The results suggest a potential means of preserving the efficacy of future antineoplastic gene therapy strategies. 相似文献
64.
Asymmetric growth of the lateral cerebral ventricle in infants with posthemorrhagic ventricular dilation 总被引:1,自引:0,他引:1
Lateral cerebral ventricular volume in 36 preterm infants with or without an intraventricular hemorrhage, and with or without posthemorrhagic hydrocephalus, was measured longitudinally and compared with the ventricular index measurements of the same ventricles. A poor correlation was found (r2 = 0.67). To determine a reason for this poor relationship, we analyzed the volumes of the regions of the ventricles by a segmental volume analysis. The occipital region of the lateral cerebral ventricle enlarged at a much faster rate (1.904 +/- 0.477 ml/day) than either the anterior region (0.546 +/- 0.253 ml/day; p less than 0.01) or the middle region (-0.209 +/- 0.334 ml/day; p less than 0.01) in infants with posthemorrhagic hydrocephalus. The rate of growth of the middle region of the lateral cerebral ventricles was the same for all infants. Linear indexes, such as the ventricular index and the lateral ventricular ratio, do not allow for accurate serial estimates of ventricular size in posthemorrhagic hydrocephalus because of asymmetric growth of the lateral cerebral ventricle. We conclude that sequential volume measurements are more useful than ventricular index measurements to follow ventricular size sequentially in infants with posthemorrhagic hydrocephalus. 相似文献
65.
A case of mycotic carotid artery aneurysm due to cervical lymphadenitis in a four-year old child is presented. Sonography and computed tomography (CT) demonstrated an irregular fluid-containing neck mass, similar in appearance to an uncomplicated abscess. Continuity with the carotid artery was suggested on sonography, and CT demonstrated intense contrast enhancement of the liquid portion of the mass. Mycotic carotid artery aneurysm is a rare, but potentially fatal, complication of cervical lymphadenitis that is detectable with noninvasive diagnostic imaging studies. 相似文献
66.
Acculturation and the probability of use of health services by Mexican Americans. 总被引:11,自引:1,他引:10
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How does level of acculturation affect the probability that Mexican Americans use general health, mental health, and human social services? We studied this question using data from a general population sample of Mexican Americans (N = 1,055). Data were elicited in face-to-face interviews. After controlling for sociodemographic and economic factors, health status, and insurance coverage, Mexican Americans who were less acculturated had significantly lower probabilities of an outpatient medical visit for physical health problems and of a visit to a mental health specialist or human service provider for emotional problems. The less acculturated with good perceived general health were especially unlikely to receive outpatient medical care. Having Medicaid coverage was associated with a larger increase in the probability of an inpatient medical admission for the more acculturated than for the less acculturated. Other individual characteristics had generally similar effects on use of medical and mental health services for both the more and the less acculturated Mexican Americans. 相似文献
67.
Effect of corticosteroid prophylaxis on lipopolysaccharide levels associated with intestinal ischemia in cats 总被引:1,自引:0,他引:1
Ischemia of the intestines damages the permeability of the intestinal wall, allowing lipopolysaccharide (LPS) (endotoxin) to leak from the gut lumen into the blood circulation, causing shock and death. We measured LPS levels associated with corticosteroid treatment vs. no treatment in cats whose superior mesenteric artery had been occluded for 60 min. In untreated cats, the preocclusion mean plasma LPS concentration remained stable at 0.069 +/- 0.015 ng/ml. Toward the end of the occlusion period, mean plasma LPS rose to 0.239 +/- 0.032 ng/ml (p less than .01). Release of the clamp and reperfusion with oxygenated blood was followed within 20 min by a large rise in plasma LPS concentration to 0.825 +/- 0.11 ng/ml (p less than .01), which had returned to preocclusion levels about 80 min later. Methylprednisolone (30 mg/kg) was infused into a second group of cats 1.5 h before SMA occlusion. In these cats there was a complete inhibition of the LPS rise both during and after occlusion. These data suggest that the reported beneficial effect of corticosteroids in the treatment of septic shock may be mediated, in part, by reducing LPS leakage from the gut. 相似文献
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Coronary sinus thrombosis was found at necropsy in a girl with spina bifida who underwent ventriculoatrial shunt revision. There was secondary myocardial infarction, close to the conducting system within the interventricular septum. We suggest that this led to cardiac arrest and sudden death. 相似文献