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1.
Liver hemangioma: US-guided 18-gauge core-needle biopsy 总被引:6,自引:0,他引:6
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BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors. 相似文献
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Nursing informatics is the synthesis of nursing science, information management science, and computer science to enhance the input, retrieval, manipulation, and/or distribution of nursing data. The literature abounds with articles stressing the unmet computer needs of nurses. Nurses must go beyond knowing computer terms and following basic program commands; they must be informatics competent. This article proposes five courses in nursing informatics to enhance all areas of nursing: practice, administration, education, and research. 相似文献
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Association of human polyomavirus JC with peripheral blood of immunoimpaired and healthy individuals
Drries Kristina Sbiera Silviu Drews Klaus Arendt Gabriele Eggers Christian Drries Rdiger 《Journal of neurovirology》2003,9(1):81-87
JC virus (JCV) infection is regularly asymptomatic in healthy individuals. In contrast, in immunocompromised individuals, highly activated virus replication may lead to PML. Peripheral blood cells (PBCs) are found to habor JCV DNA in healthy and diseased individuals and it is discussed that they might be responsible for dissemination of the virus to the central nervous system (CNS) during persistence. To better understand the role of JCV DNA in PBCs for persistent infection and pathogenesis, the authors characterized the extent of JCV infection in Ficoll-gradient purified blood cells (peripheral blood mononuclear cells [PBMCs]) of healthy and human immunodeficiency virus type 1 (HIV-1)-infected individuals. Virus activation in PBMCs from healthy JCV-infected individuals was found at a rate of 0% to 38% at low polymerase chain reaction (PCR) sensitivity. In progressive multifocal leukoencephalopathy (PML) patients, a stronger signal was found, indicating increased virus activation. JCV DNA was regularly detected in T and B lymphocytes and in monocytes at low levels. However, granulocytes were shown to be the predominant reservoir of JCV DNA harboring high copy numbers. Although the overall distribution of viral genomes holds true for the population studied, in the individual, a markedly changed pattern of distribution can be found. 相似文献
7.
Dr. C. Hessler F. Raimund J. Regelsberger J. Madert A. Ekkernkamp C. Eggers 《Der Chirurg》2007,78(10):915-927
INTRODUCTION: This study evaluated the intra- and post-surgical complications on tumor affected spines. Complications were analyzed according to selected patient groups so that risk factors could be determined. MATERIAL AND METHODS: Between January 1999 and December 2004, 401 patients underwent surgery because of spinal metastases in the Department of Traumatology, General Hospital St. Georg in Hamburg. Data were obtained from the hospital's documentary system. The results of this study were compared to other published studies. RESULTS: The average age of patients was 63 years (24-88) and there were 172 (42.9%) females and 229 (57.1%) males. A total of 118 (29.4%) patients suffered from 235 complications and 22 (5.5%) died. DISCUSSION: Patient's age >70 years, patients with a preoperative neurological deficit, and patients with heavily bleeding metastases are at high risk for complications. The dorsoventral/dorsolateral approach had the highest complication rate. 相似文献
8.
Anesthesia in 'stone man': myositis ossificans progressiva 总被引:1,自引:0,他引:1
Myositis ossificans progressiva is a rare disease leading to complete ossification of the muscular system. Very little information about this rare disease and its anesthetic implications has appeared in anesthetic literature. This disease is felt to have an autosomal dominant pattern of inheritance and is usually associated with anomalies of the hands and feet. Afflicted patients are frequently misdiagnosed in childhood as having a rheumatologic disorder. Later in life (as true bone is formed in striated muscle, ligaments, and fascia), the correct diagnosis becomes obvious. Although muscles of the heart, diaphragm, larynx, and sphincters are spared, those of the chest wall are not, and pulmonary function progressively deteriorates. Death frequently occurs as a result of a pulmonary infection. Specific anesthetic considerations include positioning to avoid injury, potential need for fiberoptic intubation or tracheostomy, decreased thoracic compliance with the need for increased ventilating pressures, and the ultimate in disuse atrophy contraindicating the use of succinylcholine. Myositis ossificans progressiva can present the anesthesiologist with interesting challenges. Anesthetic management will need to be individualized according to the severity of the disease. 相似文献
9.
Steenbergen EJ; Verhagen OJ; van Leeuwen EF; van den Berg H; von dem Borne AE; van der Schoot CE 《Blood》1995,86(2):692-702
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL. 相似文献
10.
AE Castellano G Micieli P Bellantonio MG Buzzi S Marcheselli F Pompeo F Rossi G Nappi 《Cephalalgia : an international journal of headache》1998,18(9):622-630
Intracerebral vascular reactivity induced by the nitric oxide (NO) donor isosorbide dinitrate (IDN, 5 mg sublingually) is more major and longer-lasting in migraine patients who develop delayed headache in response to the drug. The headache is purportedly due to neuronally-mediated vascular mechanisms. Indomethacin inhibits prostaglandin synthesis, which is involved in NO generation. Indomethacin also decreases cerebral blood flow by constricting precapillary resistance vessels. In the present study, the hemodynamic effects of indomethacin were evaluated in migraine patients and healthy controls by means of transcranial Doppler monitoring. Indomethacin caused a significant decrease in mean flow velocity in the middle cerebral artery. This was an additional effect to the mean velocity decrease induced by IDN. The interactions between the two drugs suggest that their effects on cerebral hemodynamics (and pain) may be of relevance both in understanding the role of NO in migraine pathogenesis and in evaluating symptomatic treatments for migraine attacks. 相似文献