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991.
M J Dunn 《Gastroenterology》1984,87(6):1392-1395
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992.
Alveolar proteinosis (AP) is characterized by excessive surfactant accumulation, and most cases are of unknown etiology. Standard therapy for AP is whole-lung lavage, which may not correct the underlying defect. Because the hematopoietic cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF) is required for normal surfactant homeostasis, we evaluated the therapeutic activity of GM-CSF in patients with idiopathic AP. Fourteen patients received 5 microg/kg/d GM-CSF for 6 to 12 wk with serial monitoring of the alveolar-arterial oxygen gradient ([A-a]DO2), diffusing capacity of carbon monoxide, computed tomographic scans, and exercise testing. Patients not responding to 5 microg/kg/d GM-CSF underwent stepwise dose escalation, and responding patients were retreated at disease recurrence. Stored pretreatment sera were assayed for GM-CSF-neutralizing autoantibodies. According to prospective criteria, five of 14 patients responded to 5 microg/kg/d GM- CSF, and one of four patients responded after dose escalation (20 microg/kg/d). The overall response rate was 43% (mean improvement in [A-a]DO2 = 23.2 mm Hg). Responses lasted a median of 39 wk, and were reproducible with retreatment. GM-CSF was well-tolerated, with no late toxicity seen. The only treatment-related factor predictive of response was GM-CSF-induced eosinophilia (p = 0.01). Each of 12 patients tested had GM-CSF-neutralizing autoantibodies present in pretreatment serum. We conclude that GM- CSF has therapeutic activity in idiopathic AP, providing a potential alternative to whole-lung lavage.  相似文献   
993.
Sabin CA  Walker AS  Dunn D 《Lancet》2004,364(9436):757-8; author reply 758
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994.
The predictive value of the measurement of changes in ST segment elevation was assessed as a non-invasive marker of coronary artery reperfusion after thrombolytic treatment. Forty five patients with acute myocardial infarction (23 anterior, 22 inferior) of less than six hours' duration were given thrombolytic treatment by either the intravenous (n = 28) or the intracoronary route (n = 17). A proportional value for the shift in ST segment, termed the fractional change, was calculated both from 12 lead electrocardiograms and from the Holter tape for each patient. Coronary artery patency in an initial group of 22 patients (training group) was associated with a fractional change value of greater than or equal to 0.5 (100% specific, 88% sensitive by Holter analysis; 100% specific, 94% sensitive by 12 lead electrocardiogram). This rule performed well when it was applied to a test group of 17 patients (100% specific, 93% sensitive by Holter analysis; and 67% specific, 93% sensitive by 12 lead electrocardiogram). Linear discriminant analysis was then used to determine which features gave the best separation of those in whom there was reperfusion and those in whom there was not. This gave 100% specificity and 100% sensitivity when applied to the training group for either the 12 lead electrocardiogram or Holter monitoring. When it was applied to the test group, the sensitivity was maintained at 100%, but the specificity dropped to 33% irrespective of whether the basis of the test was Holter monitoring or the 12 lead electrocardiogram. These results suggest that a fractional change of >/= 0.5 calculated from a single lead showing myocardial injury is a useful non-invasive marker of reperfusion. The technique can be applied to either 12 lead electrocardiograms or Holter monitoring. The use of a more complex classification increased the sensitivity of the test at the expense of its specificity.  相似文献   
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996.
Twenty-one elderly patients with essential hypertension, all over 65 years of age, were subjected to automated noninvasive 24-hour blood pressure measurement. Readings were obtained every 7.5 minutes throughout the day. The data were analyzed with respect to: correlation between office and ambulatory pressure measurements; possible differences in the circadian blood pressure pattern; and the existence of hypertensive or atherosclerotic cardiovascular complications. In all patients, the office systolic pressures were significantly higher than the ambulatory daytime pressures; diastolic pressures were similar. At night, two patterns of blood pressure emerged. In one there was a further fall in both systolic and diastolic pressures to normotensive levels, whereas the other pattern revealed no change in diastolic pressure, although systolic pressure increased significantly to similar levels as measured in the office. The prevalence of hypertensive or atherosclerotic cardiovascular complications in the patients with the first pattern was significantly less than in the group of patients with the second pattern (chi square, P less than 0.025). The data reported herein indicate that ambulatory blood pressure monitoring may help in the overall clinical evaluation of elderly patients with hypertension.  相似文献   
997.
A deficiency of adenosine deaminase, an enzyme important in purine nucleoside catabolism, is associated with a severe combined immunodeficiency disease in children. Inhibition of this enzyme in vitro and in vivo results in an impairment in lymphoblast proliferation. We have investigated the pharmacologic inhibition of this enzyme by 2'-deoxycoformycin in 15 patients with hematologic malignancies. Biochemical consequences of the administration of this agent were closely monitored in erythrocytes, nucleated peripheral blood and bone marrow cells, serum, and urine. A marked rise in erythrocyte dATP was accompanied by a depletion of ATP in those patients exhibiting toxicity. Most patients excreted large amounts of deoxyadenosine but not adenosine in the urine. Serum deoxyadenosine rose in patients demonstrating a marked decrease in cell mass. The biochemical disturbances and clinical toxicity, including hepatic, renal, and conjunctival abnormalities, were usually reversible. Central nervous system toxicity, which potentially was the most serious consequence, was associated with high erythrocyte dATP/ATP ratios and high levels of cerebrospinal fluid deoxyadenosine. In patients with lymphoma and leukemia, objective responses were observed but were short- lived. Patients with chronic lymphocytic leukemia receiving weekly low doses of the drug demonstrated minimal toxicity and some efficacy. The chemotherapeutic potential o 2'-deoxycoformycin, as either a single agent or in combination with Ara-A, merits further exploration.  相似文献   
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ObjectiveTo describe what women of reproductive age who received primary care at a refugee health clinic were using for contraception upon arrival to the clinic, and to quantify the unmet contraceptive needs within that population.DesignRetrospective chart review.SettingCrossroads Clinic in downtown Toronto, Ont.ParticipantsWomen of reproductive age (15 to 49 years) who first presented for care between December 1, 2011, and December 1, 2012. To be included, a woman had to have had 2 or more clinic visits or an annual health examination. Exclusion criteria for the contraception prevalence calculation were female sexual partner, menopause, hysterectomy, pregnancy, or trying to conceive.ResultsOverall, 52 women met the criteria for inclusion in the contraceptive prevalence calculation. Of these, 16 women (30.8%) did not use any form of contraception. Twelve women were pregnant at some point in the year and stated the pregnancy was unwanted or mistimed. An additional 14 women were not using contraception but had no intention of becoming pregnant within the next 2 years. There were no women with postpartum amenorrhea not using contraception and who had wanted to delay or prevent their previous pregnancy. In total, 97 women were married or in a union, or were sexually active. Unmet need was calculated as follows: (12 + 14 + 0)/97 = 26.8%.ConclusionThere was a high unmet contraceptive need in the refugee population in our study. All women of reproductive age should be screened for contraceptive need when first seeking medical care in Canada.  相似文献   
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