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Chest radiographs of 18 newborns treated with endotracheal instillation of human surfactant for respiratory distress syndrome (RDS) were compared with those of 18 similar but untreated infants. In the treated infants, severity of RDS significantly improved after surfactant administration. Most treated infants (16/18) exhibited a left-to-right shunt, presumably through a patent ductus arteriosus; similar findings were noted in untreated infants (17/18). Complications of respiratory assistance in the treated infants included transient pulmonary interstitial emphysema (n = 1), pneumothorax (n = 1), and mild (n = 4) to moderate (n = 2) bronchopulmonary dysplasia; the incidences of these complications did not exceed those in untreated infants. In three treated infants, a transient interstitial lung disease developed 3-4 days after surfactant administration.  相似文献   
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Non-immunologic and immunologic stimulation of mast cells have been compared. Non-immunologic stimulation relys heavily on cellular Ca, is unaffected by neuraminidase treatment, shows a rapid inactivation, and elicits no increase in the incorporation of 3H-methyl groups into the lipid fraction. In contrast, stimulation by immunologic agents relys primarily on extracellular Ca, is inhibited by neuraminidase treatment, shows a comparatively slow rate of inactivation, and causes a significant increase in the incorporation of 3H-methyl groups into the lipid fraction. We found no evidence of cross-inactivation or desensitization between immunologic and non-immunologic agents. However, pretreatment of mast cells with neurotensin desensitized them to subsequent stimulation by compound 48/80. Our results support the hypothesis that immunologic and non-immunologic agents activate exocytotic mast cell secretion via separate mechanisms.  相似文献   
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Interleukin-1 alpha (IL-1 alpha) can act as both a hematopoietic growth factor and a stimulant of cellular and humoral immune responses. To promote acceleration of hematologic recovery and induce immune antitumor activity, we initiated a phase I/II dose escalation trial of 6-hour daily infusions of recombinant human IL-1 alpha after autologous transplantation. Forty patients with Hodgkin's disease (n = 9) and non- Hodgkin's lymphoma (n = 31) transplanted with unmobilized autologous peripheral blood stem cells or bone marrow stem cells received daily 6- hour infusions of IL-1 alpha (day 0 to day +13) at daily doses between 0.1 to 10 micrograms/m2/d; 7 patients received only 7 planned days of IL-1 alpha (day 0 through 6). Most patients received all 14 days of therapy, although 5 patients discontinued treatment early (after 1 to 6 doses) because of fever and severe chills. Toxicity included IL-1 alpha- related fever (occurring on a median of 9 of 14 treatment days), fatigue, and severe chills. Hypotension was dose-limiting and led to discontinuation of IL-1 alpha in both patients receiving 10 micrograms/m2/d. IL-1 alpha-treated patients receiving 3.0 micrograms/m2/d (the maximum tolerated dose) achieved neutrophil recovery (absolute neutrophil count greater than 500/microL) significantly earlier (median, 12 days; range, 11 to 27) than untreated control patients or those receiving IL-1 alpha at 0.1 to 1.0 micrograms/m2/d (median, 27; range, 9 to 63; P < .0001). In addition, the IL-1 alpha patients' bone marrows at day +14 were significantly enriched with committed myeloid progenitor cells. Strong trends to earlier freedom from red blood cell (P = .06) and platelet (P = .09) transfusions were also noted after IL-1 alpha treatment. This earlier hematopoietic engraftment after 3.0 micrograms/m2/d IL-1 alpha allowed earlier hospital discharge (median, 25 v 37 days for control or low- dose IL-1 alpha patients [P < .0001]) and a concomitant reduction (by $38,000) in median hospital charges (P = .01). The clinical toxicities of IL-1 alpha infusion are substantial, though not life-threatening. The accelerated hematopoiesis and immune response activation observed in this trial suggest the value of its further investigation in controlled trials and perhaps in combination with other hemopoietins after transplantation.  相似文献   
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We report the first clinical experience with a new method for projective imaging of blood vessels (angiography) using magnetic resonance. Vascular contrast is produced noninvasively by the phase response of moving protons. Diastolic and systolic gated images produce, respectively, flow signal and flow void; the difference image is a map of the pulsatile flow: an arteriogram. Preliminary studies are presented of the lower extremities of one healthy volunteer and four patients (one each with occlusive disease, soft-tissue tumor, arteriovenous malformation, and venous femoral-popliteal graft). Patient data are compared with accompanying conventional arteriograms, and the new method is discussed.  相似文献   
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Benacerraf  BR; Stryker  J; Frigoletto  FD  Jr 《Radiology》1989,171(1):151-153
Certain fetal cranial abnormalities found on second-trimester sonograms can be signs of an open spina bifida. In particular, an abnormal configuration of the cerebellum, known as the banana sign, has been associated with neural tube defects. To further evaluate the usefulness of this sign, the authors compared images of the posterior fossa in 23 fetuses who had documented neural tube defects with those of 38 control fetuses who underwent sonography because of an elevated maternal serum alpha-fetoprotein level. Twenty-two of the 23 fetuses with neural tube defects had compression and anterior alignment of the cerebellar hemispheres (the banana sign), and follow-up confirmed the presence of an open neural tube defect. One fetus had a normal-appearing posterior fossa; however, the neural tube defect at birth was completely covered with skin. Four of the neural tube defects were difficult to see sonographically, and the abnormal configuration of the cerebellum, as well as the flattening of the frontal bone (lemon sign), was instrumental in suggesting the correct diagnosis. The 38 control fetuses had normal-appearing posterior fossae.  相似文献   
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