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181.
JM Bardin  ; Y Sultan 《Transfusion》1990,30(5):441-443
Hemophilia B patients are usually treated for the prevention and control of bleeding episodes with a plasma derivative containing the four vitamin K-dependent clotting factors (PPSB). Prothrombin complex concentrate and the French PPSB concentrate are known to be thrombogenic when used in long-term treatment of surgical patients. The present study reports two cases of thrombotic episodes following surgery in PPSB-treated hemophilia B patients. Since 1986, there has been available a factor IX (FIX) concentrate depleted of the other vitamin K-dependent clotting factors and virally inactivated by the solvent-detergent method. This preparation has been used as replacement therapy in six patients with severe hemophilia B who were to undergo orthopedic surgery. The management of the patients before and after operation was without any thrombotic complication or undesirable side effects. The present study suggests that there is a need for an FIX preparation devoid of the other vitamin K-dependent clotting factors for long-term therapy of hemophilia B patients.  相似文献   
182.
The American Association of Blood Banks (AABB) requires that blood samples used for pretransfusion testing of recently transfused (or pregnant) patients must be obtained within 3 days of scheduled transfusions. This requirement, which became effective in July 1988, amended Standard G2.000 of the AABB, which previously required that pretransfusion testing must be done on blood samples obtained within 2 days of scheduled transfusions. The present study was designed to estimate the risk associated with adopting the amended version of Standard G2.000. Sixty patients who developed significant unexpected alloantibodies after transfusion were studied retrospectively. Thirteen of the 60 patients were found to have newly detectable antibodies within 83 hours of a sample reported to be negative for the new antibody. Had the amended version of Standard G2.000 been in effect, the detection of some of these antibodies might have been delayed up to 24 hours. It was estimated that the implementation of the new AABB requirement at the authors' institution could potentially place about 1 in 3000 transfused patients at risk for an acute or delayed hemolytic transfusion reaction.  相似文献   
183.
To understand better the relationships between blood-group antigens and bacterial constituents, examples of 23 gram-negative bacteria (representing the 10 genera Citrobacter, Edwardsiella, Enterobacter, Escherichia, Klebsiella, Proteus, Pseudomonas, Salmonella, Serratia, and Shigella) were tested for the presence of Kl-like antigens by hemagglutination-inhibition (HAI) assays against both IgG and IgM anti-Kl. Saline-suspended whole organisms, cell-free culture media, and disrupted organisms were used to test for such antigens in, on, and secreted by the microorganisms examined. Disrupted organisms of an isolate of Shigella sonnei nonspecifically inhibited IgG anti-Kl as well as IgG antibodies of the specificities Kpb, Fya, S, and c. However, only Escherichia coli 0125:B15, subtype 12808, had specific K1-like activity (no activity with other IgG [(k, Kpb, Jka, Fya, S, c] and IgM [A, B, M, P1] antibodies). Disrupted organisms inhibited IgM but not IgG anti-K1 in the HAI assay. A second subtype, E. coli 0125:B15, subtype 12809, exhibited no K1-like activity. These findings support the report of K1 activity in cell-free broth cultures of E. coli 0125:B15 (subtype unspecified). Thus, although not all E. coli 0125:B15 possesses K1-like activity, the finding of such activity in at least one E. coli subtype confirms the idea that bacterial components may play a role in the production of naturally occurring antibodies directed against non-ABO red cell antigens.  相似文献   
184.
Headache in lacunar stroke   总被引:1,自引:0,他引:1  
The presence of headache within a 72-h interval of stroke onset was investigated in a cohort of 145 lacunar infarcts. Fourteen (10%) experienced diffuse or bilateral headache. Hypertension was less frequent (43 vs 76%; 95% CI: 6 to 60%) and of shorter duration (2.4 vs 7.8 years; t = 2.29; p = 0.02) among patients with headache. Leukoaraiosis was less frequent (40% vs 71%; 95% CI: −57 to −7%) and severe (7 vs 24%; 95% CI: −33 to −2%) in patients with headache. Age, sex, stroke risk factors, type of lacunar stroke, mode of onset, stroke severity, ultrasound and other CT findings were similar in patients with and without headache. No differences in the sixth month neurological or functional outcome were detected between lacunar patients with and without headache. Headache in lacunar stroke cannot be predicted by the clinical characteristics of the stroke and is not due to coexisting cardiembolism, intra or extracranial disease. Hypertensive small-vessel disease is less common and severe in lacunar strokes with associated headache.  相似文献   
185.
A group of unique Epstein-Barr virus-containing cell lines was derived from the bone marrow of three patients with X-linked agammaglobulinemia. Efforts to obtain cell lines from the peripheral blood of these patients were uniformly unsuccessful. Immunofluorescence analyses as well as biosynthetic studies with [(35)S]methionine indicated unusual patterns of Ig synthesis in many of these bone marrow derived lines. Seven of the lines were of particular interest in that two produced no Ig of any type; two others showed no Ig by fluorescence but small amounts by [(35)S]methionine labeling; one expressed only cytoplasmic μ chains without any evidence of light chain synthesis, and two produced primarily μ chains with only slight amounts of light chains. One of the lines without membrane or cytoplasmic Ig studied in detail grew like a typical lymphoid line and was carried in intermittent culture over a period of 2 yr without Ig expression. One line grew quite differently and resembled the round cell type described previously, which has been obtained from a variety of sources. The cell line with cytoplasmic μ chains and no light-chain expression had the characteristic properties of pre-B cells. Three normal type Ig-producing cell lines also were obtained from the patients. The accumulated evidence obtained in the present study indicates that these unusual cell lines represent normal precursor cells of the B-cell lineage; these grew out in these cases because of the virtual absence of mature B cells that ordinarily overgrow the culture system. However, the possibility that in certain instances they reflect abnormal Ig synthesis characteristic of the disease has not been ruled out.  相似文献   
186.
BACKGROUND: To verify the criteria for human T-lymphotropic virus (HTLV) seropositivity in Western blot (WB) proposed by the Retrovirus Study Group of the French Society of Blood Transfusion, 186 blood donations that were repeatedly reactive in HTLV enzyme-linked immunosorbent assay, selected according to their WB pattern, were tested by polymerase chain reaction (PCR) and radioimmunoprecipitation assay (RIPA). STUDY DESIGN AND METHODS: In two commercially available WBs, 12 samples were confirmed as positive (rgp21+p19+p24) and 174 were interpreted as indeterminate (one or two reactivities to these proteins). The primer pairs used for the PCR allowed the amplification of type I (HTLV-I) or type II (HTLV-II) (or both) sequences. The RIPA was performed with two 35S-labeled cell lines: HTLV-I infected HUT 102/B2 and HTLV-II-infected MoT. RESULTS: Of the 12 positive samples, 11 were classified as HTLV-I-positive and one as HTLV-II-positive. Among the 174 indeterminate samples, three (WB pattern: rgp21+, p19+, p24-) were HTLV-I positive in PCR (one of them was positive in RIPA also); the other 171 were HTLV negative. CONCLUSION: In the study of a population in which 97 percent of HTLV infections are due to HTLV-I, these data support the three-protein criteria (rgp21, p19, and p24) for a positive blot reading. No HTLV infection was observed when rgp21 did not react. Consequently, p19 and/or p24 band patterns represent false reactivity and do not require PCR or RIPA confirmation. To discriminate between false- and true-positive results in the absence of MTA-1 or K55 reactivity, PCR and/or RIPA is required only when rgp21 reactivity is associated with one gag band (p19 or p24).  相似文献   
187.
The use of eye-patches allows to modulate the visual information treating process. Twelve subjects with a left unilateral spatial neglect, randomly divided into three groups — non treated, treated by right eye complete patching, treated by right hemifield patching — were assessed at 1 month and 3 months after acute episode, by means of functional and neuropsychological tests. Results in the subjects treated by complete eye-patch [5]show an improvement of all the assessment parameters whatever the unilateral spatial neglect seriousness degree may be. The progression is less convincing in the patients treated by eye-patch in right hemifield. The effects of the different modalities of occultation interpreted on the basis of anatomo-physiological and psychophysiological patterns of attention, suggest the role of ocular occultation in the initial, voluntary and directed, coven attention recovery and secondary of the automatic and divided overt attention.  相似文献   
188.
Isolated headache as the presenting clinical manifestation of intracranial tumors: a prospective study. Cephalalgia 1994;1'4:270-1. Oslo. ISSN 0333-1024We prospectively studied over two years the incidence of headache as the initial and isolated clinical manifestation of adult patients suffering from intracranial tumors ( n = 183). Fifteen patients (8%) exhibited headache as their first and isolated clinical manifestation. Age, sex, neoplasm localization, or pathological diagnosis did not correlate with the presence of headache. Posterior fossa location and hydrocephalus, though not reaching statistical significance, were more frequent in patients who presented with headache as the first symptom. At the moment of diagnosis, 59 (31%) of the patients admitted to headache, though only I out of the 15 patients starting as headache still had this symptom as the only manifestation. From our experience in adults, isolated headache for longer than 10 weeks will only exceptionally be secondary to an intracranial neoplasm.  相似文献   
189.
190.
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   
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