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Ten thrombocytopenic patients (platelets < 10–24 × 10(9)/L) who were refractory to platelet transfusion were investigated for their responsiveness to staphylococcal protein A column therapy. Nine patients had previously been treated with steroids, intravenous immune globulin, and/or other forms of immunosuppressive therapy without improvement in their transfusion response. All patients were receiving multiple platelet transfusions without achieving 1-hour corrected count increments (CCIs) > or = 7500. Eight patients had antibodies that reacted with platelets and were directed against HLA class I antigens, ABO antigens, and/or platelet-specific alloantigens. Plasma (500-2000 mL) from each patient was passed over a protein A silica gel column and then returned to the patient. Patients received from 1 to 14 treatments. A positive response to protein A therapy was defined as at least a doubling of the pretreatment platelet count and/or two successive 10- to 120-minute posttransfusion CCIs > or = 7500. Following plasma treatments, 6 of 10 patients responded with daily platelet counts that averaged 48 +/− 11 × 10(9) per L as compared with counts of 16 +/− 7 × 10(9) per L (p < 0.0005) before treatment. Posttransfusion CCI values determined in four of these patients averaged 2480 +/− 810 and 10,010 +/− 3540 (p < 0.005) before and after treatment, respectively. In contrast, among the four unresponsive patients, platelet counts averaged 10 +/− 9 and 13 +/− 10 × 10(9) per L (p = NS), respectively, while posttransfusion CCIs were 700 +/− 1410 and 1520 +/− 2460 (p = NS), respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Adipsin gene expression is severely diminished in certain forms of genetic and acquired rodent obesity. Common to many of these models of obesity is decreased sympathetic nervous system (SNS) activity. In addition, treatment of MSG obese mice with the sympathomimetic drug mixture ephedrine and caffeine restores adipsin deficiency to normal, while reversing obesity. Based on these observations, we hypothesized that adipsin gene expression might be regulated through changes in SNS activity with deficient adipsin gene expression in obesity being the result of impaired SNS activity. In the present study we used three models to assess the role of the SNS in regulating adipsin gene expression. First we exposed mice to the cold (4 degrees C), a potent activator of SNS activity. Second, we chemically sympathectomized mice with 60H-dopamine. Third, we treated mice with BRL 26830A, an atypical beta adrenoreceptor agonist. In contrast to our initial hypothesis, these studies demonstrate that alterations of SNS activity do not affect adipsin gene expression in normal mice. Neither increased SNS activity secondary to cold exposure nor decreased SNS activity resulting from sympathectomy alter serum adipsin concentration or adipsin mRNA levels in white (WAT) and brown adipose tissue (BAT). Surprisingly, treatment of lean mice with BRL 26830A decreases both adipsin serum concentrations and adipsin mRNA levels, suggesting a potential role for atypical beta adrenoreceptors in pathways that suppress adipsin expression in vivo. The significance of this observation with respect to adipocyte physiology is unclear at present. Future studies will be aimed at defining the molecular mechanisms by which BRL 26830A suppresses adipsin gene expression and the physiological significance of this effect. 相似文献
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Perforated colorectal neoplasms: correlation of clinical, contrast enema, and CT examinations 总被引:2,自引:0,他引:2
Hulnick DH; Megibow AJ; Balthazar EJ; Gordon RB; Surapenini R; Bosniak MA 《Radiology》1987,164(3):611-615
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm. 相似文献
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