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991.
A 25-year-old woman complained of anasarca and was admitted to Sakura National hospital on the presumptive diagnosis of nephrotic syndrome with 10.7 g of 24-hour urinary protein. At first, lupus nephritis with antiphospholipid antibody syndrome was suspected because of prolongation of APTT, existence of lupus anticoagulant and elevation of serum anticardiolipin antibody titer (IgM) in addition to positive ANA, lymphocytopenia and the biologically false positive test for syphilis (BFPTS). On day 28 of hospitalization, renal biopsy findings revealed severe endocapillary cell damage, such as swelling and proliferation of endothelial cells, fragmentation and double contour of the basement membrane walls, which were located only in the capillary lumens with a few thrombi. Immunofluorescent micrography revealed the absence of specific immunoglobulin or complement deposit. Therefore, the diagnosis of lupus nephritis was negated as these findings were suggestive of characteristic glomerulopathy due to primary antiphospholipid antibody syndrome. She was treated initially with oral prednisolone 60 mg and intravenous infusion of heparin 20,000 units daily. Moreover, cyclophosphamide 750 mg was administered intravenously as pulse therapy on day 13 as her serum level of CH50 had fallen suddenly, and hemodialysis was necessary because her renal function had deteriorated and she was suffering from cough and orthopnea with overhydratin. After the combined therapy, BFPTS disappeared and APTT returned to the normal range: dialysis treatment was not required further after the 4th hemodialysis. Thereafter, renal function improved and complete remission of nephrotic syndrome was obtained. This patient was a case of primary antiphospholipid antibody syndrome in which endothelial cell damage was located exclusively in the capillary lumens and pulse cyclophosphamide therapy in addition to prednisolone and anticoagulant was effective. We present this instructive case to promote understanding of the pathogenesis of primary antiphospholipid antibody syndrome.  相似文献   
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We examined the effects of hand dominance and the patients' stated preference of the sleeping position on the survival of vascular accesses for hemodialysis in different locations. Analysis was made of vascular access survival times after 1, 126 vascular access surgeries performed between January 1, 1989, and December 31, 1994. We found that hand dominance and access site were not related to any survival differences in patients with autogenous fistulas, but thigh grafts on both sides had greater survival than arm grafts. The preferential side for sleeping similarly did not seem to affect access survival, but patients who stated a sleep preference on the side opposite their vascular graft tended to have longer access survival time.  相似文献   
994.
BACKGROUND: Irradiation of platelet concentrates (PCs) with ultraviolet-B (UVB) light inactivates the contaminating white cells and might be an alternative to filtration for the prevention of alloimmunization to HLA antigens and subsequent refractoriness to further platelet transfusions in multiply transfused patients with bone marrow failure. STUDY DESIGN AND METHODS: Patients with hematologic malignancy, mainly acute myeloid leukemia, were prospectively assigned in a random manner to receive either UVB-irradiated or control, nonirradiated PCs. All patients were given red cells that were white cell reduced by filtration. Transfusion efficacy and alloimmunization were assessed by means of corrected count increments, requirement for red cells and PCs, and measurement of lymphocyte-reactive antibodies. RESULTS: UVB-irradiated PCs had a clinical efficacy similar to controls as judged by corrected count increments at 1 to 6 and 12 to 24 hours and by the median requirement for red cell and platelet transfusions. Alloimmunization determined by measurements of lymphocyte-reactive antibodies using both conventional and antiglobulin-augmented lymphocytotoxicity techniques was not abolished in recipients of UVB-irradiated PCs (4/30, 13%) but was less than that in controls (5/20, 25%; p = NS). The mean number of platelet transfusion episodes prior to the occurrence of alloimmunization was greater in the control group (27 vs. 10; p = 0.017). CONCLUSION: In this trial, UVB irradiation did not diminish the clinical efficacy of platelet transfusions. There was a small but nonsignificant reduction alloimmunization, but no difference in refractoriness of the two groups was observed. Larger prospective randomized studies are required to confirm these findings and to compare UVB irradiation with white cell reduction.  相似文献   
995.
In mid-January 1993, an outbreak of Escherichia coli O157:H7 infections associated with eating hamburger patties at a fast-food restaurant chain (chain A) was reported in Washington State. From mid-December to mid-January, 9 cases of E coli O157:H7-associated bloody diarrhea and the hemolytic-uremic syndrome had been reported in San Diego County, California. A total of 34 persons had bloody diarrhea, the hemolytic-uremic syndrome, or E coli O157:H7 organisms isolated from stool during the period November 15, 1992, through January 31, 1993. Organisms of E coli O157:H7 identified from 6 persons were indistinguishable from those of the Washington outbreak strain. Illness was associated with eating at chain A restaurants in San Diego (odds ratio, 13; 95% confidence interval, 1.7, 99) and with eating regular-sized hamburgers (odds ratio, undefined; lower-limit 95% confidence interval, 1.3). Improved surveillance by mandating laboratory- and physician-based reporting of cases of E coli O157:H7 infection and the hemolytic-uremic syndrome might have alerted health officials to this outbreak sooner, which could have resulted in earlier investigation and the institution of measures to prevent more cases.  相似文献   
996.
Superantigens are a class of immunostimulatory molecules produced by bacteria and viruses. Their potent immune effects are due to their unique ability to bind to the major histocompatibility complex (MHC) outside the antigen-binding cleft and to stimulate T cells in a T-cell receptor (TCR) Vbeta-specific manner. Structural studies have revealed the binding sites involved in the MHC/superantigen/TCR complex. The bacterial superantigens are responsible for a number of syndromes, including food poisoning and toxic shock syndrome, but their effects may be not only acute but also chronic and complex. Recent evidence suggests that superantigens may be relevant to the pathogenesis of autoimmune and immunodeficiency disorders. To illustrate the detrimental effects of superantigens on disease outcome, evidence demonstrating the modulation of experimental allergic encephalomyelitis, an animal model for multiple sclerosis, by superantigen, as well as the potential role of superantigens in HIV pathogenesis of AIDS, will be presented. The information presented may provide valuable insight into the role of superantigens in autoimmunity and HIV infection.  相似文献   
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999.
Fluorescence in situ hybridization, or chromosome painting, has become an invaluable tool in the cytogenetic evaluation of historical or chronic exposure because it can be used to detect stable genetic damage, such as translocations, which persist through cell division, quickly and easily. The recent development of chromosome-specific composite DNA probes for the mouse has allowed the use of chromosome painting in this commonly used animal model. In order to measure the persistence of radiation-induced translocations, C57BL/6 female mice were given a whole body acute dose of 0, 1, 2, 3 or 4 Gy 137Cs gamma rays at 8 weeks of age. Metaphase chromosomes from both peripheral blood and bone marrow cells were obtained from four mice in each dose group at 1, 8, 15 and 30 days post-irradiation. Chromosomes 2 and 8 were painted, while the remaining chromosomes were counterstained with propidium iodide. DAPI counterstain was used to differentiate between translocations and dicentrics because it brightly labels the centromeric heterochromatin. The equivalent of 100 cells from each tissue was scored from each mouse. The results show that the percentage of reciprocal translocations, at least at doses of 3 Gy or lower, did not decrease with time in either tissue. In contrast, the frequency of non-reciprocal translocations induced by doses of 3 Gy or lower, remained unchanged in the peripheral blood, but decreased after a week in the bone marrow, then remained constant. An increase in these two types of aberration was observed between 15 and 30 days in the bone marrow and may have been due to clonal expansion. Dicentrics decreased with time in both tissues, almost none remained in the bone marrow after 8 days. These data suggest that reciprocal translocations are persistent and will serve as an effective biodosimeter for radiation exposure.  相似文献   
1000.
Attitudes of 40 interns towards rational drug use (RDU) were assessed, using a standardized Likert type scale. The assessment was repeated after 4 months to evaluate the effect of usual working conditions of the hospital. After this period, the attitudes had slided towards negative side (p < 0.01). At this point, an intervention in the form of a workshop was provided for half the group while other half served as control. A repeat assessment after another period of 4 months revealed that the attitudes of test group returned towards positive side (p < 0.01) while control group maintained its negative attitudes.  相似文献   
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