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61.
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The field of renal transplantation has grown exponentially as a result of a greater understanding of the immune system and the advent of numerous immunosuppressive agents. Although African Americans and whites have benefited from these advances, equivalent long-term success eludes African Americans who are disadvantaged in gaining access to renal transplantation. This review summarizes the obstacles for African Americans to end-stage renal disease(ESRD) care, focusing on transplantation. Factors that predispose African Americans for ESRD, impede this ethnic group from timely transplantation, and negatively influence graft survival are examined. Possible solutions to these persistent problems are offered.  相似文献   
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64.
Electromyographic and nerve conduction data in evaluation of 66 burn patients revealed a 29 per cent incidence of peripheral polyneuropathy. Patchy myopathic findings, probably related to multiple injections, were noted in the proximal muscles of 22 patients. Entrapment mononeuropathies of the ulnar, median and peroneal nerver were found. These neuromuscular abnormalities produce clinical motor and sensory deficits which limit rehabilitation in the burned patient, and further work is immediately needed to determine the pathophysiology of these abnormalities.  相似文献   
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Heterotopic pregnancy (simultaneous intrauterine and extrauterine pregnancy) is an extremely rare clinical phenomenon occurring approximately 1 in 30,000 pregnancies (1) or 1 in 2,000,000 live births (2). There have been 435 cases reported in the world literature up to 1956 (3). Simultaneous viability in heterotopic pregnancy is an even rarer event occurring in only 10.6% of cases (3).  相似文献   
67.
Immune thrombocytopenia is frequently encountered in medical practice and is generally accepted as being caused by an IgG antibody. The capability of detecting platelet-bound IgG as a diagnostic and therapeutic modality is critical for appropriate care and management of patients with idiopathic thrombocytopenic purpura (ITP), as well as other immune thrombocytopenias We have modified our previous assay (Br J Haematol 37:265, 1977) by employing protein A and PAP as a labeled antibody. Surface bound platelet IgG was quantitated by phase contrast microscopy after incubation with PAP, graded per 100 platelets and expressed as a reactive index (RI). Controls (n=13) had RIs ranging from 0.49 to 0.72 (mean 0.63 ± 0.02 SE). The nonimmune thrombocytopenic group (n=7) had an RI ranging from 0.58 to 0.72 (mean 0.64 ± 0.01 SE). In contrast, the immune thrombocytopenic group (n=28) had RIs ranging from 1.04 to 1.75 (mean 1.43 ± 0.03 SE). Platelet-associated IgG was evaluated further by absorbing representative sera samples from each group against washed granulocytes, red cells and platelets Only when sera from the immune thrombocytopenic group were absorbed against platelets did the reactive indices of pre- and postabsorption samples change significantly. These findings suggest that our assay is clinically applicable in detecting platelet-associated IgG in immune thrombocytopenia and has the advantage of being rapid, reproducible and easy to perform in a clinical laboratory.  相似文献   
68.
The present study examines gene delivery to cultured motor neurons (MNs) with the Rabies G protein (RabG)-pseudotyped lentiviral equine infectious anemia virus (RabG.EIAV) vector. RabG.EIAV-mediated beta-galactosidase (RabG.EIAV-LacZ) gene expression in cultured MNs plateaus 120 h after infection. The rate and percent of gene expression observed are titer-dependent (P < 0.001). The rat IGF-I cDNA sequence was then cloned into a RabG.EIAV vector (RabG.EIAV-IGF-I) and was shown to induce IGF-I expression in HEK 293 cells. MNs infected with RabG.EIAV-IGF-I demonstrate enhanced survival compared to MNs infected with RabG.EIAV-LacZ virus (P < 0.01). In addition, IGF-I expression in cultured MNs induced profound MN axonal elongation compared to control virus (P < 0.01). The enhanced motor neuron tropism of RabG.EIAV previously demonstrated in vivo, together with the trophic effects of RabG.EIAV-IGF-I MN gene expression may lend this vector to therapeutic application in motor neuron disease.  相似文献   
69.
PURPOSE OF REVIEW: Acute renal failure remains a significant cause of morbidity and mortality in adults and children. Despite advances in understanding the pathophysiology of acute renal failure, little progress has been made in its treatment. This review assesses the recent data on current and promising new therapies for acute renal failure. RECENT FINDINGS: The first section of the review describes the recent therapies that have been used in humans, all of whom have been adults. The second section evaluates the use of agents given in experimental animal models during or after the onset of acute renal failure. The third section describes the many animal studies using therapies before the onset of experimental renal failure. The final section discusses how the emerging field of stem cell research might be used to treat acute renal failure. SUMMARY: Among the recent studies in humans, the most intriguing have been the use of atrial natriuretic peptide in patients with nonoliguric renal failure and isotonic sodium bicarbonate infusions to prevent radiocontrast medium-induced renal failure. Among the agents used in animal studies, those with the greatest potential were hepatocyte growth factor and ethyl pyruvate, because they seem to protect against or accelerate recovery from acute renal failure after the renal insult. Finally, stem cell therapy may someday offer the best option for recovery from acute renal failure.  相似文献   
70.
Vaso-occlusive pain is a frequent manifestation of sickle cell disease, but most clinical studies have documented only those pain episodes for which patients seek acute care or require hospitalization. Based on limited previous studies, the authors suggest that pain episodes managed at home are more frequent then those resulting in acute care management but likely share a common pathophysiology. The authors determined the characteristics of vaso-occlusive pain managed at home in 30 subjects (ages 6-19 years) using a self-report diary daily for 6 months. A total of 175 pain episodes were reported in 4,885 days, with 51% lasting 1 day or less. Severe pain, rated as 7 to 10 on a 10-point scale, was reported on 12% of pain days, but most pain was of mild to moderate intensity. A combination of baseline hematologic parameters and biomarkers assessing erythrocyte/endothelial cell adhesion, including hematocrit, fetal hemoglobin, and adhesion ratio, were statistically significant predictors of pain frequency in statistical analyses. Given the overlap in clinical features and predictive hematologic parameters of home-managed and acute care-managed pain, both likely represent a continuum of frequency and severity rather than distinct clinical entities. The higher frequency of these home-managed episodes suggests their potential utility as additional outcome measures in studies of vaso-occlusive pain.  相似文献   
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