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991.
Anti-PL 4 in patients with systemic lupus erythematosus with severe renal and haematological disease
Marguerie C; Bunn CC; Black CM; So AK; Walport MJ 《QJM : monthly journal of the Association of Physicians》1997,90(5):347-352
Anti-PL 4 is an autoantibody which binds to a 150 kDa polypeptide and is
found in approximately 1% of SLE sera. The clinical and laboratory features
of 16 patients who have had anti-PL 4 detected in their serum are
presented. Anti-PL 4 is highly specific for SLE (100%) and identifies a
population of patients who typically develop severe renal (75%) and
haematological disease (100%).
相似文献
992.
Little information is available regarding the risk of human immunodeficiency virus type 1 (HIV-1) infection for patients transfused before routine anti-HIV-1 screening of blood donors was instituted in March 1985. A model was developed for estimating both the proportion and the number of transfusion recipients in the San Francisco Bay area who were infected by HIV-1 during each of the 7 years preceding routine donor screening for anti-HIV-1. The model is based on analysis of 1) donation histories of HIV-1-infected donors identified at the regional blood center; 2) HIV-1 seroprevalence estimates for homosexual and bisexual men in San Francisco; and 3) HIV-1 infection and survival rates for recipients traced by the Transfusion Safety Study and Irwin Memorial Blood Centers' Look Back Program. The incidence of transfusion-associated HIV-1 infection is estimated to have risen rapidly from the first occurrence in 1978 to a peak in late 1982 of approximately 1.1 percent per transfused unit. The decrease after 1982 coincided with the implementation of high-risk donor deferral measures. It is estimated that, overall, approximately 2135 transfusion recipients were infected with HIV-1 in the San Francisco region alone. This number suggests a higher prevalence of transfusion-associated HIV-1 infection than has been generally recognized and indicates the need for continued tracing of potentially exposed recipients. The data also strongly support the effectiveness of early donor education and self-exclusion measures and emphasize the importance of continued research and development in this area. 相似文献
993.
The In(Lu) gene, which inhibits the expression of Lutheran blood group antigens by red cells (RBCs), also down-regulates the expression of an 80-kD glycoprotein, In(Lu)-related p80, by both RBCs and a subset of white cells. This study examined the expression of multiple-RBC p80 epitopes by autosomal and X-linked recessive-type Lu(a-b-) RBCs in order to explore the relationship, if any, between expression of In(Lu)-related p80 and Lutheran antigens. Both autosomal and X-linked types of recessive Lu(a-b-) RBCs expressed near-normal to increased amounts of p80 antigens, as measured by radioimmunoassay. P80 from both types of recessive Lu(a-b-) RBCs had apparently normal molecular weight in denaturing polyacrylamide gels and showed normal sensitivity to digestion by trypsin and chymotrypsin. Thus, the absence of Lutheran antigens on recessive-type Lu(a-b-) RBCs is not associated with decreased or absent p80 antigens. Furthermore, the XS2 gene probably does not act via a mechanism similar to that of the In(Lu) gene, since the expression of p80 remains undiminished in X-linked recessive-type Lu(a-b-) RBCs. 相似文献
994.
The capacity of mitogen-responsive T cells to “home” to their tissue of origin, analyzed by means of chromosome markers 下载免费PDF全文
Lance and Taub (1) showed that when radioactively labeled lymphocytes were injected into a syngeneic mouse and the lymph node cells of this animal transferred to a second syngeneic recipient, the proportion of radioactivity found in the lymph node relative to the amount present in the spleen of the secondary recipient had increased markedly. The interpretation of this result was that some lymphocytes have the capacity to “home” to their organ of origin. The purpose of the experiments described here was to test the “homing” copacity of T cells by a method that did not involve radioactive labeling. It has been shown elsewhere that some or all mouse T cells are stimulated to divide in culture by the mitogens phytohemagglutinin (PHA) and concanavalin A (Con A) (2). We therefore elected to inject karyotypically distinct lymphocytes into syngeneic recipients and to follow their subsequent distribution by culture of lymph node and spleen cells of the recipient with PHA or Con A. In this manner the homing capacities of spleen and lymph node T cells could be determined, and furthermore, the effects of labeling with chromium-51 ((51)Cr) could be assayed with respect to the persistence of mitogen responsiveness in the injected cells. 相似文献
995.
Although the risks of allogeneic blood transfusions are small, it is wise to limit donor exposure whenever possible. A program has been developed in which one donor provided all red cell (RBC) units for each patient awaiting elective surgery. Patients were mostly children who were ineligible for autologous blood donation. Seventy-three patients and 115 donors (mostly parents) entered the program. Of the 115 donors, 90 (78%) were eligible to participate and 25 (22%) were ineligible; 21 were ineligible because of RBC incompatibility. For each of the 73 patients, one eligible donor was selected to donate all RBC units. Preoperative RBC orders were 1 to 2 units for 41 patients and > or = 3 units for 32 patients. Of the 73 donors, 58 (79%) gave all RBC units ordered; 15 (21%) failed to complete all donations, but only 1 because of anemia (hematocrit < 33% [0.33]). Of 73 patients entered, 46 (63%) underwent transfusion, and 27 (37%) did not. Of 46 patients transfused, 38 (83%) received only single-donor RBCs. Thus, the RBC needs of nearly all pediatric elective surgery patients were provided by a single donor for each patient. Single-donor blood programs should be considered for elective surgery patients who are ineligible for autologous blood donation and who would otherwise be exposed to multiple donors. 相似文献
996.
A blood cell separator with a specialized separation chamber ([TNX-6]CS- 3000 Plus) was developed for the collection of platelet concentrates with higher platelet yields and lower white cell contamination than obtained with the standard blood cell separator (CS-3000). To compare these devices, normal donors were scheduled for paired plateletpheresis procedures spaced 4 weeks apart, with one procedure using the CS-3000 Plus and the other using the CS-3000. Overall, the platelet yield per unit (mean +/− SEM) was 4.3 +/− 0.1 × 10(11) with the CS-3000 Plus versus 3.7 +/− 0.1 × 10(11) with the CS-3000 (p < 0.001), and the white cell contamination per unit (mean +/− SEM) with the former was 2.4 +/− 0.7 × 10(6) versus 84.1 +/− 21.1 × 10(6) with the latter (p < 0.001). The sequence of procedures (i.e., the order in which the devices were paired) was selected randomly, and similar results were found regardless of sequence. When donors with predonation platelet counts of > or = 200 × 10(9) per L (n = 21) were studied separately, 76 percent of the collections by the CS-3000 Plus contained > or = 4 × 10(11) platelets versus 34 percent of those by the CS-3000 (p < 0.01), and 93 percent of the collections by the former contained < 5 × 10(6) white cells (69% contained < 1 × 10(6)) versus 0 percent of those by the latter (p < 0.01). Thus, platelet collections with the TNX-6 chamber consistently demonstrated high platelet yields and strikingly low white cell contamination–qualities that justify converting standard devices to devices with a TNX-6 chamber. 相似文献
997.
Rajman I; Lip GY; Cramb R; Maxwell SR; Zarifis J; Beevers DG; Kendall MJ 《QJM : monthly journal of the Association of Physicians》1996,89(10):771-778
In a prospective longitudinal study in 17 women, we investigated the
effects of surgical menopause and subsequent oestrogen-only hormone
replacement therapy (HRT) on plasma concentrations of total cholesterol,
HDL cholesterol, LDL cholesterol, triglyceride and LDL subfractions
profile. Plasma LDL is a heterogeneous population of particles of varying
size, density and chemical composition. The predominance of small LDL
particles is a newly-recognized risk factor for coronary artery disease.
The LDL score is used to describe LDL subfractions profile and the greater
the score, the higher the proportion of small LDL particles. Six weeks
after hysterectomy and bilateral oopherectomy, total cholesterol and
triglyceride concentrations were significantly increased (p < 0.01) as
well as the LDL score (p < 0.05). After 6 weeks of oestrogen-only HRT,
total cholesterol concentration was significantly lower and HDL cholesterol
concentration significantly higher than before the treatment (p < 0.05).
At the same time, mean LDL score significantly increased and in none of the
women did LDL subfractions profile change favourably.
相似文献
998.
van der Vorst MM den Hartigh J Wildschut E Tibboel D Burggraaf J 《Critical care (London, England)》2007,11(5):R111
Introduction
The objective of the present study was to explore a continuous intravenous furosemide regimen that adapts to urine output in neonates treated with extracorporeal membrane oxygenation (ECMO). 相似文献999.
1000.
BACKGROUND: To avoid the need, in serial apheresis donors, either to delay plateletpheresis until a predonation platelet count is completed or to obtain a postdonation count after each procedure, a statistical model has been developed to predict the postdonation platelet count from the donor predonation platelet count, weight, and hematocrit. STUDY DESIGN AND METHODS: Predonation and postdonation platelet counts were measured in two groups of approximately 100 consecutive donors (Group A to test the model and Group B to validate it), and the postdonation counts were calculated with the model. Using stepwise multiple linear regression from donor data, estimated postdonation platelet counts were found to be comparable to the postdonation platelet counts actually measured. RESULTS: Estimated postdonation platelet counts × 10(9) per L (mean +/− SD) for each group, respectively, were Group A, 195 +/− 35, versus actual platelet counts of 195 +/− 39 (p = 0.43), and Group B, 183 +/− 36, versus actual platelet counts of 189 +/− 34 (p = 0.14). Sensitivity and specificity, respectively, were Group A, 57 and 99 percent and Group B, 62 and 99 percent. CONCLUSION: For most serial apheresis donors, application of this predictor model should preclude the need to obtain an extra postdonation platelet count. 相似文献