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31.
We undertook a prospective study of standard peripheral pulse oximetry versus a modified pulse oximeter probe applied to the tongue in order to determine the efficacy of this alternative monitoring site in children with thermal injuries. Ten patients with a mean age (± SD) of 7.5 ± 4.5 yr were studied on 15 occasions. The mean weight +- SD) was 31.4+- 13.7 kg and percent surface area burn (± SD) was 56+- 21%. A total of 1,992 min of anaesthesia time was monitored. Both sites functioned simultaneously 47% of the time; the lingual but not the peripheral site functioned 28% of the time and only the peripheral site and not the lingual functioned 22% of the time. Neither site functioned 3% of the time. The tongue oximeter provided 563 min more monitoring time than the peripheral sites. The tongue oximeter also functioned in children with peripheral vasoconstriction when the peripheral sensor failed and was less susceptible to electrocautery interference. The tongue oximeter is a reasonable adjunct but not a substitute for peripheral oximetry since its application is limited to paralyzed, intubated patients.  相似文献   
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To determine the influence of infiltrating lobular histology on local tumor control, the authors studied 49 patients with Stages I and II infiltrating lobular breast carcinoma treated by limited excision of the tumor and radiotherapy between 1968 and 1981 (median follow-up, 75 months). Results were compared with those in 561 cases of infiltrating ductal carcinoma similarly treated during the same period. The 5-year actuarial risk of local recurrence was similar for patients with infiltrating lobular or ductal carcinoma when the latter was evaluated as a single group (12% versus 11%). However, the 12% 5-year actuarial local recurrence risk for patients with infiltrating lobular carcinoma was intermediate between that for patients with infiltrating ductal carcinomas with an extensive intraductal component (23%) and those without an extensive intraductal component (5%). The pattern of recurrence in the breast was similar in the infiltrating lobular and ductal groups. All recurrences in patients with infiltrating lobular carcinoma and 80% of recurrences in the infiltrating ductal group occurred in the vicinity of the primary tumor (P = not significant). None of the clinical or morphologic features examined significantly influenced the risk of local recurrence in patients with infiltrating lobular carcinoma. The authors conclude that combined conservative surgery and radiotherapy appear to be a reasonable treatment option for patients with infiltrating lobular carcinoma, but further follow-up will be required to confirm these results.  相似文献   
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Twelve patients with frequent ventricular premature depolarizations (VPDs) received amiodarone, 600 mg/day, for up to 8 weeks. On days 0, 1, 4, 8, 15, 22, 36, and 57 of treatment, 24-hour ambulatory ECGs were obtained, and multiple blood samples were taken for determination of amiodarone and desethylamiodarone plasma concentrations. All patients had at least 75% suppression of VPDs. The mean duration of therapy before the onset of antiarrhythmic effect was 13.2 days (range 1 to 36 days). Trough amiodarone and desethylamiodarone plasma concentrations at the time of onset of antiarrhythmic effect were 0.86 +/- 0.48 mg/L and 0.23 +/- 0.15 mg/L, respectively. Sixty-seven percent of patients responded at amiodarone concentrations below 1.0 mg/L. For each patient there was a progressive decrease in frequency of VPDs as both amiodarone and desethylamiodarone concentrations increased. Regression modeling indicated that both amiodarone and desethylamiodarone plasma concentrations explained significant variability in the frequency of VPDs, and amiodarone and desethylamiodarone plasma concentrations were highly correlated with each other. There was a trend for desethylamiodarone to explain more variability in frequency of VPDs than amiodarone.  相似文献   
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Monocyte chemoattractant protein 1 (MCP-1) is a member of the chemokine family of cytokines that mediate leukocyte chemotaxis. The potent and specific activation of monocytes by MCP-1 may mediate the monocytic infiltration of tissues in atherosclerosis and other inflammatory diseases. We have isolated cDNAs that encode two MCP-1-specific receptors with alternatively spliced carboxyl tails. Expression of the receptors in Xenopus oocytes conferred robust mobilization of intracellular calcium in response to nanomolar concentrations of MCP-1 but not to related chemokines. The MCP-1 receptors are most closely related to the receptor for the chemokines macrophage inflammatory protein 1 alpha and RANTES (regulated on activation, normal T expressed and secreted). The identification of the MCP-1 receptor and cloning of two distinct isoforms provide powerful tools for understanding the specificity and signaling mechanisms of this important chemokine.  相似文献   
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BACKGROUND: The mainstay of treatment for pemphigus is systemic corticosteroids. Different adjuvants have been used to reduce side-effects of long-term corticotherapy. Gold is an anti-inflammatory drug used in autoimmune diseases, whose use has waned with the advent of new immunosuppressive agents. OBJECTIVE: To study the outcome of the use of intramuscular gold treatment of pemphigus vulgaris refractory to previous therapies. METHODS: Thirteen patients with pemphigus vulgaris who had failed to respond to several prior therapies were treated with aurothiomalate, as a steroid-sparing agent. Patients were monitored to assess disease activity and gold toxicity. RESULTS: Seven patients achieved complete remission. Four patients were able to taper prednisone doses, although pemphigus flared when prednisone was discontinued or reduced. Toxicity was observed in the other two patients. CONCLUSIONS: In 53.4% of the patients, the use of chrysotherapy resulted in the complete clearing of the disease, discontinuation of all systemic therapies and induced a long-term clinical remission. Prednisone doses were able to be reduced in the remaining 46.6%. Any side-effects were reversible with drug discontinuation. Gold therapy showed efficacy as a secondary line treatment in refractory pemphigus vulgaris.  相似文献   
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BACKGROUND: Equilibration of hemoglobin concentration after transfusion has been estimated to take about 24 hours, but some studies have shown that earlier measurements reflect steady-state values in persons who have not bled recently. This study was aimed at assessing the changes over time in hemoglobin concentration after transfusion in acutely anemic patients because of recent bleeding. STUDY DESIGN AND METHODS: Thirty-two normovolemic patients recovering from an acute bleeding episode who were no longer thought to be bleeding and who received a 2- unit red cell transfusion were studied. At baseline and 15, 30, 60, and 120 minutes and 24 hours after transfusion, hemoglobin concentration and hematocrit values were measured. RESULTS: The administration of 2 units of packed red cells elicited a 24-hour increase of 22.4 +/− 6.8 g per L in hemoglobin concentration. Hemoglobin values were not different at any of the defined posttransfusion times. Hematocrit levels experienced similar changes over time. Agreement between 15-minute and 24-hour values was excellent, as only 6 percent of patients exhibited a clinically significant difference (> 6 g/L) between the hemoglobin measurements. CONCLUSION: Hemoglobin and hematocrit values rapidly equilibrate after transfusion in normovolemic patients who are recovering from an acute bleeding episode. This fact would allow a rapid assessment of the effects of transfusion and of the recurrence of bleeding in patients remaining at risk.  相似文献   
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Human prostate cancer (PC) cell lines possess epidermal growth factor (EGF) receptors and secrete EGF-related polypeptides. We used an EGF receptor-blocking antibody (anti-EGF.R) to demonstrate a functional autocrine loop, as well as the interaction between this and the effects of linoleic acid (LA), an omega-6 fatty acid, on PC cell growth. The anti-EGF.R competed effectively with [125I]EGF for receptors on DU145 PC cells, and on a high-passage DU145 variant (DU145M); when added to the culture medium, it suppressed both DU145 and DU145M cell growth in a dose-dependent manner. LA, a precursor for eicosanoid synthesis, had little effect on DU145 cell growth rate but stimulated DU145M growth in a concentration-related manner over a range of 0.25-2.0 micrograms/ml. anti-EGF.R (10(-9) M) caused suppression of LA-stimulated growth of DU145M cells in serum-free medium, which was prevented by the addition of 2 nM EGF. We conclude that an EGF.R-mediated autocrine loop is involved in PC cell growth regulation and that at least one site of action may be the synthesis of eicosanoids from their LA precursor.  相似文献   
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