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31.
BACKGROUND: Before 1987, fewer than 50 patients per year at the authors' laboratory had a positive antibody detection test due to antepartum Rhesus immunoprophylaxis. However, after 1987, a marked increase was observed in the number of patients who had received Rh immune globulin (RhIG) during pregnancy as part of routine antepartum Rh immunoprophylaxis. In anticipation that an increased use of RhIG during pregnancy would increase the number of patients in whom anti-D was detected by this laboratory, a protocol was developed to abbreviate the process required to identify anti-D. Although this protocol was adopted primarily to address an anticipated increase in antenatal RhIG usage in women, it was also applied to alloimmunized Rh-negative males. STUDY DESIGN AND METHODS: When an Rh-negative patient (male or female) had a reactive screening test for unexpected antibodies and met certain other criteria, the patient's serum was tested with a three-vial set of Rh-negative reagent red cells (Rh-negative screening RBCs), instead of with panels of typed RBCs (panel RBCs), for the identification of anti- D or the detection of non-D antibodies. If the serum under test did not agglutinate or hemolyze Rh-negative screening RBCs, anti-D was identified and no further testing was performed. If the serum agglutinated or hemolyzed Rh-negative screening RBCs, conventional testing with panel RBCs was done to determine the antibody specificity. RESULTS: Rh-negative patients (n = 1174) who had reactive screening tests for unexpected antibodies were tested with Rh-negative screening RBCs; 1079 were found to have anti-D as a single antibody. Seven of these patients subsequently developed a non-D alloantibody, after transfusion or pregnancy, and one patient had anti-C that escaped detection at the time of initial testing with Rh-negative RBCs (a false- negative result). Ninety-two patients had anti-D in combination with a non-D antibody, and three patients had a non-D antibody but not anti-D. Use of the anti-D identification protocol actually reduced the laboratory workload by 176 College of American Pathologists workload units per month, in spite of a marked increase in the number of patients in whom anti-D was detected. No hemolytic transfusion reaction was attributed to the abbreviation of anti-D identification. CONCLUSION: The identification of anti-D may be abbreviated without jeopardizing patient safety. Such a protocol can reduce laboratory workload and might be particularly appealing to health care facilities that perform antibody detection testing on large numbers of Rh-negative pregnant women, especially if antepartum RhIG is administered routinely. 相似文献
32.
Iodinated contrast media-induced nephropathy: pathophysiology, clinical aspects and prevention 总被引:2,自引:0,他引:2
Summary— Administration of iodinated contrast media (CM) for radiographic purposes is a preoccupying cause of acute renal failure. This review of the literature deals with what is known about physiopathology, clinical course, risk factors and prevention. Factors involved in the pathophysiology of CM-induced acute renal failure are vasoconstriction, direct tubular cell injury and tubular obstruction by casts. In the case of pre-existing renal hypoperfusion, CM may disturb the complex interaction between factors which modulate renal haemodynamics by increasing vasoconstrictor factors, notably endothelin peptides. The renal medulla, a zone characterized by a high metabolic activity and a low oxygen tension, may be a specific target for CM-induced effects. CM-induced nephropathy (CMN) is essentially observed in patients with one or more associated risk factors (chronic renal failure, dehydration, diabetes mellitus with impaired renal function, multiple myeloma, large CM volume, intra-arterial rather than intravenous route, etc). There is much debate as to whether newer low osmolar CM (LOCM) are better tolerated than conventional high osmolar CM (HOCM). Most of the animal studies clearly demonstrate the advantages of LOCM over HOCM. Clinical literature is far more confusing, although some recent studies and one meta-analysis demonstrate that LOCM are better tolerated in patients with impaired renal function. The low number of comparative clinical trials carried out in high risk patients, wide variability in CMN definitions, limited number of patients enrolled and inadequacy of various selected endpoints may explain difficulties experienced in demonstrating this advantage. Furthermore, while hydration is correctly maintained during clinical trials, this is not always true in clinical practice. Such a discrepancy could lead to underestimation of the potential advantage of LOCM over HOCM. Effective prevention should associate the correct hydration of patients, identification and, when possible, optimal correction of risk factors, avoidance of repeated CM injections within a short period of time and temporary disruption of treatment with other nephrotoxic drugs (non steroidal antiinflammatory drugs, aminoglycosides, etc). 相似文献
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GF Tremblay JM Anderson DLW Davidson 《Journal of neurology, neurosurgery, and psychiatry》1982,45(2):175-178
A case of cerebral mycosis fungoides co-existing with progressive multifocal leucoencephalopathy presented with dementia. Brain biopsy established the diagnosis of mycosis fungoides after cerebrospinal fluid examinations and computerised tomographic scanning of the brain produced non-specific abnormalities. 相似文献
38.
JM Schulze 《Clinical genetics》2009,75(3):227-229
Mutations of LRTOMT, a fusion gene with alternative reading frames, cause nonsyndromic deafness in humans
Ahmed et al. (2008)
Nature Genetics 40: 1335–1340. 相似文献
Ahmed et al. (2008)
Nature Genetics 40: 1335–1340. 相似文献
39.
The effectiveness of a treatment protocol for male lower urinary tract symptoms in general practice: a practical randomised controlled trial
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Roelf JC Norg Kees van de Beek Piet JM Portegijs CP Onno van Schayck J Andr Knottnerus 《The British journal of general practice》2006,56(533):938-944
BACKGROUND: Randomised controlled trials have shown the efficacy of several treatment modalities for lower urinary tract symptoms (LUTS) in selected populations. The effectiveness in daily practice has hardly been investigated, especially in primary care and is dependent on choices between all possible treatment options and best investigated in a comprehensive study, including all treatment modalities (watchful waiting, alpha-blockers, 5-alpha-reductase inhibitors, and surgery). AIM: Assessment of the effectiveness of a comprehensive treatment protocol for LUTS in primary care. DESIGN OF STUDY: Randomised controlled trial. SETTING: Fourteen general practices in the Netherlands. METHOD: Intervention: treatment protocol based on a formalised expert opinion. Control condition: usual care. Study population: 208 subjects with moderate to severe LUTS (IPSS > or =8, median = 13). OUTCOME MEASURES: symptom severity (IPSS [International Prostate Symptom Score]), bother score (Dan-PSS [Danish Prostate Symptom Score]), and maximum urinary flow (Q(max)); incidence of acute urinary retention and urinary tract infections. RESULTS: In the intervention group markedly more subjects used an alpha-blocker at end of follow-up than in the usual care group (24% versus 6%). No significant differences were found between intervention and control group in IPSS, Q(max) or Dan-PSS. CONCLUSION: alpha-blockers and watchful waiting are the most frequent treatment modalities for LUTS in primary care. Our study showed no evidence that a protocol using well-defined indications for all possible treatment modalities based on a formalised expert opinion procedure has added value. Based on our results, we cannot recommend a broadening of the indication for alpha-blockers, which, however, seems to be the current trend. 相似文献
40.
Hendrik Wermann Hans Stoop Ad JM Gillis Friedemann Honecker Ruud JHLM van Gurp Ole Ammerpohl Julia Richter J Wolter Oosterhuis Carsten Bokemeyer Leendert HJ Looijenga 《The Journal of pathology》2010,221(4):433-442
Differences in the global methylation pattern, ie hyper‐ as well as hypo‐methylation, are observed in cancers including germ cell tumours (GCTs). Related to their precursor cells, GCT methylation status differs according to histology. We investigated the methylation pattern of normal fetal, infantile, and adult germ cells (n = 103) and GCTs (n = 251) by immunohistochemical staining for 5‐ cytidine. The global methylation pattern of male germ cells changes from hypomethylation to hypermethylation, whereas female germ cells remain unmethylated at all stages. Undifferentiated GCTs (seminomas, intratubular germ cell neoplasia unclassified, and gonadoblastomas) are hypomethylated, whereas more differentiated GCTs (teratomas, yolk sac tumours, and choriocarcinomas) show a higher degree of methylation. Embryonal carcinomas show an intermediate pattern. Resistance to cisplatin was assessed in the seminomatous cell line TCam‐2 before and after demethylation using 5‐azacytidine. Exposure to 5‐azacytidine resulted in decreased resistance to cisplatin. Furthermore, after demethylation, the stem cell markers NANOG and POU5F1 (OCT3/4), as well as the germ cell‐specific marker VASA, showed increased expression. Following treatment with 5‐azacytidine, TCam‐2 cells were analysed using a high‐throughput methylation screen for changes in the methylation sites of 14 000 genes. Among the genes revealing changes, interesting targets were identified: ie demethylation of KLF11, a putative tumour suppressor gene, and hypermethylation of CFLAR, a gene previously described in treatment resistance in GCTs. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献