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Thrombocytopoietic properties of oncostatin M   总被引:1,自引:2,他引:1  
Oncostatin M (OM) is a 28-kD glycoprotein that exhibits a panoply of biologic effects. Based on histologic observations of increased splenic megakaryocytes in nude mice implanted with an OM-secreting cell line, the thrombocytopoietic properties of OM in mice were investigated in culture and in vivo. Alone, OM did not induce megakaryocytic colony formation, but in combination with murine interleukin-3 (IL-3), OM markedly enhanced colony formation. The effects of OM on colony formation were similar to those of IL-6. OM alone augmented acetylcholinesterase in short-term marrow cultures. In normal mice, the administration of OM augmented platelet counts without increasing other circulating blood cell counts. The increment in counts exceeded that observed with IL-6. The kinetics of the OM response suggested that maximal increases in platelets occurred 3 days after the cessation of OM administration, irrespective of the duration of administration. In irradiated mice, OM administration accelerated platelet recovery and prevented the decrease in red blood cells observed in irradiated control animals. The data show that OM behaves as a megakaryocytic maturation factor in vitro and augments platelet production in vivo. Based on these animal data, OM may have potential clinical utility as a thrombocytopoietic agent.  相似文献   
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This study involved an evaluation of two versions of the "premature aging" theory of chronic alcoholism: the accelerated aging and increased vumerabHty versions. The major dependent measures used were the tests included in Reitan's brain age quotient (BAO), a series of neuropsychological tests known to be sensitive to the effects of alcoholism and aging. Subjects were 40 chronic alcoholic inpatients and 40 matched controls, divided into age groups by; decade, ranging from the 30s to the 60s. It was proposed that an j interaction between age and presence or absence of alcoholism, with BAO test differences between alcoholics and controls widening as age increases, would support the increased vulnerability version, while the absence of such aw interaction would support the accel-] erated aging version. The results dearty favored the accelerated aging version, with merited BAO test differences between alcoholics, and controls appearing even in the 30-year-old groups. It was concluded that chronic ateohoftcs tend to perform at levels found for nonalconoiics 10 years their senior, but the discrepancy between, alcoholics and nonalcohoics does not increase with age.  相似文献   
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Inflammatory breast cancer is a distinct clinicopathologic entity that accounts for 1 percent of all cases of breast cancer. The diagnosis should be strongly suspected on the basis of the distinctive clinical findings, which include edema of the breast, inflammation, wheals, and a typical reddish-purple color of the overlying skin. Pathologic examination usually shows infiltration of the dermal lymphatics with carcinoma. Evidence of distant metastatic spread is more frequent than with other types of breast cancer and is seen in approximately 30 percent of patients. The five-year disease-free survival rate is less than 5 percent when local therapy alone (mastectomy and/or local radiotherapy) is used. The addition of combination chemotherapy to high-dose local radiotherapy has improved the five-year survival rate to approximately 30 percent. The potential for long-term survival is limited to the subgroup of patients with only local-regional disease at the time of diagnosis. Patients with inflammatory breast cancer should be treated with combined-modality therapy using combination chemotherapy and high-dose radiotherapy to the breast, since this approach is potentially curative. The fatalism formerly associated with this diagnosis is no longer warranted, particularly in patients with local-regional disease. Failure to employ intensive combined-modality treatment will deny some patients a chance for long-term survival.  相似文献   
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Drug-induced lung injury   总被引:2,自引:0,他引:2  
Lung injury is an increasing cause of morbidity and mortality in patients treated with cytotoxic and noncytotoxic drugs. Prompt diagnosis is important because early drug-induced lung injury will often regress with the cessation of therapy. Diagnosis requires a high index of suspicion because infection, radiation pneumonitis, and recurrence of the underlying disease can manifest clinically and radiologically in a similar manner. Because the lungs have only a limited number of histopathologic responses to injury, including pulmonary edema/diffuse alveolar damage, NSIP, BOOP, EP, and pulmonary hemorrhage, knowledge of these manifestations and the corresponding radiologic manifestations can often be useful in suggesting a diagnosis of drug-induced lung injury. An understanding of the drugs most commonly associated with lung injury can also facilitate diagnosis.  相似文献   
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Introduction : Hypertrophic scar is a devastating sequel to burns and other tangential skin injuries. It follows deep dermal injuries and does not occur after superficial injuries. Nitric oxide (NO) plays many important roles in wound healing from inflammation to scar remodeling. Studies have shown that expression of nitric oxide synthase and nitric oxide production are decreased in human hypertrophic scar. However little is known about NO involvement in the early stages of hypertrophic scarring, because of the lack of an animal model. It was recently reported that the female red Duroc pig (FRDP) makes thick scar, which is similar to human hypertrophic scar. We hypothesized that NO production in wounds on the female, red Duroc pig is similar to that of human hypertrophic scar and that NO involvement in deep wounds is different from that in superficial wounds. Methods : Superficial (0.015” to 0.030”) and deep (0.045” to 0.060”) wounds were created on the backs of four FRDPs. Biopsies were collected at weeks 1.5, 4, 8 and 21 post wounding including samples of uninjured skin. Nitric oxide levels were measured with the Griess reaction assay and normalized with tissue protein level. Results : Superficial wounds healed with an invisible scar whereas the deep wounds healed with scar resembling mild hypertrophic scar. The thickness of the scars from the deep wounds was significantly greater than uninjured skin and healed superficial wounds (p < 0.01). NO levels were increased at 1.5 weeks in deep wounds compared to superficial wounds and uninjured skin (p < 0.05). At 8 weeks, NO levels in deep wounds had returned to the level of uninjured tissue and superficial wounds. By 21 weeks, NO levels had decreased significantly when compared to superficial wounds (p < 0.01). There were no differences in NO levels between uninjured skin and superficial wounds at any time point (p > 0.05). Conclusions : NO production is similar in late, deep wounds on the female, red Duroc pig to that reported in the literature for human hypertrophic scar further validating this animal model. NO production is quite different after deep wounds as compared to superficial wounds in the FRDP. Early elevation in nitric oxide production might account for excessive inflammation in deep wounds that become thick scars in the FRDP. Nitric oxide regulators and effects at early stages of scar formation should be elucidated further and the FRDP appears to be a useful model.  相似文献   
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