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21.
Cancer patients were given a recombinant mutant interferon by alternating IM and IV injections with weekly escalation of doses from 0.1 to 400 million U. Antibodies specific to the interferon of the IgG class were detected in 24 of 30 patients using an indirect enzyme-linked immunosorbent assay. Serum from only 1 of the 30 patients had detectable ability to neutralize interferon biological activity. Thein vivo interferon serum level, assayed as antiviral activity immediately after IV injection, was not lower than levels seen in the absence of antibodies. Antibodies did not alter the kinetics of clearance of interferon from the serum after IV administration. Antibody levels progressively decreased when interferon administration was discontinued. In most patients antibody levels decreased during a maintenance period when interferon was being administered only by the IV route. In a subsequent trial interferon was given IV, and antibody developed in only 2 of 36 patients. In contrast, in a trial in which interferon was given IM, 20 of 25 patients developed antibody. No antibody-related clinical sequelae could be detected in any of these patients.  相似文献   
22.
Journal of Prevention - Youth Mental Health First Aid (YMHFA) is a gatekeeper training designed to assist professionals in their identification and response to youth mental illness. Despite...  相似文献   
23.
Seven healthy male volunteers had their light sensitivity (melatonin suppression) and melatonin phase measured before and after treatment with temazepam (20 mg) for 7 days. Temazepam did not alter the circadian phase of melatonin secretion (the Dim Light Melatonin Onset, the timing of the peak of secretion), the total melatonin secretion nor the sensitivity of melatonin secretion to suppression by full spectrum light. This is an important negative finding which suggests that the short half-life benzodiazepine hypnotic temazepam does not confound tests of light sensitivity or melatonin phase.  相似文献   
24.
Central venous parenteral nutrition (PN) is frequently used in preterm infants. Although central venous catheters (CVC) permit reliable delivery of hypertonic solution, they may be associated with more serious complications than when a peripheral venous infusion is used. The aim of this randomised prospective study was to compare complications of central versus peripheral venous access using Silastic catheters identical expect for intravascular length. Eighty such devices were inserted, 38 central (CVC), 42 peripheral (PVC). Catheter life was not significantly different between groups: median (range) CVC 10d (2-25); PVC 7d (1-22) with no difference in overall complication rate. Although peripherally sited catheters tended not to function for as long as CVCs, they offer a useful alternative to central venous catheterisation.  相似文献   
25.
Depletion of adenosine triphosphate precursors, such as myocardial adenosine, during global ischemia results in poor postischemic adenosine triphosphate repletion and functional recovery. Neonatal hearts may be more resistant to this deleterious effect of ischemia, because they are characterized by low 5'-nucleotidase activity, which may result in higher sustained endogenous myocardial adenosine triphosphate precursor levels during ischemia. Adult hearts, however, have high levels of 5'-nucleotidase activity leading to depleted precursors during ischemia and poor postischemic functional recovery. Augmenting myocardial adenosine exogenously during ischemia in adult hearts has a beneficial effect on recovery. The present study tested if preservation of nucleotide precursors, better adenosine triphosphate repletion, and enhanced postischemic myocardial recovery in adult hearts could be achieved with a "neonatal" strategy. Therefore 5'-nucleotidase inhibitors were administered to isolated, perfused adult rabbit hearts subjected to 120 minutes of ischemia (at 34 degrees C) to determine if this improved functional recovery. Hearts received St. Thomas' Hospital cardioplegic solution (control hearts) or cardioplegic solution containing 5'-nucleotidase inhibitors: pentoxifylline, thioinosine, [s-(p-nitrophenyl)-4-thioinosine], or thioinosine's dimethyl sulfoxide vehicle alone. After ischemia and reperfusion, recovery of systolic function, diastolic function, and myocardial oxygen consumption was significantly better with 5'-nucleotidase inhibition. No changes in coronary flow were noted. We speculate and are pursuing the theory that the mechanism of 5'-nucleotidase inhibition's favorable action is due to preventing the catabolism, transport, and loss of nucleotide precursors during ischemia, maintaining adenosine triphosphate precursor availability.  相似文献   
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27.
Formal retrospective case review and sudden infant death   总被引:2,自引:0,他引:2  
A review of 24 consecutive sudden infant deaths was undertaken to evaluate the importance of the various stages in the postmortem assessment of such cases. Death in three cases was caused by obvious trauma. Of the remainder, 16 were attributed to sudden infant death syndrome (SIDS), 4 to accidental asphyxia (identified by death scene examination and/or formal case review) and 1 to a lingual thyroglossal duct cyst. Three (14%) of 21 deaths thought to be SIDS after postmortem examination were attributed to asphyxia following subsequent formal case review.  相似文献   
28.
An assessment of a non-invasive technique for measurement of stroke distance was made using a portable Doppler ultrasound machine. The aim was to determine the measurement error of repeated stroke distance measurements (Within-observer variability) and to assess measurement agreement between two operators (between-observer variability). The measurement error (within-observer variability) for both operators was similar at approximately 2 cm. However, the measurements of the two operators (between-observer variability) did not agree well. Using the mean (SD) of three readings by each operator, the mean difference between the operators was -0.21 cm (1.96) giving a 95% confidence interval for the differences of -4.0 to +3.6 cm. There were significant positive and negative correlations between stroke distance and a variety of variables (age, height, weight, heart rate), but the relations were weak. The results indicate that the Doppler ultrasound technique for measurement of stroke distance would best be used to study trend changes in an individual patient, or subject, by a single operator.  相似文献   
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We previously reported that papillomas can arise from the follicular epithelium of v-Ha-ras transgenic TGxAC mice. Since the viable-yellow mutation (A(vy)) of the mouse agouti gene which regulates coat color pigmentation by acting within the micro-environment of the hair follicle has been shown to function as a tumor promoter in the liver, we hypothesized that it may also play a role in TGxAC skin tumorigenesis. Endogenous agouti protein product was detected in the outer root sheath of anagen hair follicles following plucking of the hair shaft, but not in the interfollicular epithelium, in TGxAC mice on an FVB/N genetic background. It was also detected in papillomas from these mice produced by 12-O-tetradecanoylphorbol-13-acetate (TPA) treatment or plucking. Expression of the A(vy) allele in the v-Ha-ras transgenic TGxAC mouse line results in an approximately 2-fold increase in papilloma development compared with controls which did not carry the A(vy) allele following twice-weekly treatment with 1.25, 2.5 or 5.0 microg TPA. In addition, TPA-treated, papilloma-bearing F1 mice which carried the A(vy) allele, but not F1 mice which did not carry the A(vy) allele, exhibited a syndrome of humoral hypercalcemia mediated by parathyroid hormone-related protein (PTHrP) that led to weight loss, hypercalcemia and hypophosphatemia. Thus, we conclude that the A(vy) allele can influence the development of skin tumors and PTHrP-mediated humoral hypercalcemia in v-Ha-ras transgenic TGxAC mice.   相似文献   
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