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101.
102.
Two pregnant women were treated for both insulin-dependent diabetes and sickle cell disease. Careful application of treatments developed for each of these conditions allowed both pregnancies to be successfully carried to term. 相似文献
103.
Adolescents frequenting indoor tanning facilities may have an increased risk of skin cancer. The high level of indoor tanning
by this age group may be due, in part, to the large number of tanning facilities in US cities. This study examined how facilities
are distributed throughout one large county. Based on ecological models, it was predicted that tanning facilities are more
likely to be located within certain neighborhoods based on the neighborhood’s distributions of demographic factors, including
income, educational attainment, race/ethnicity, age, and sex. We also explored whether selected aspects of the built environment,
including the numbers of high schools and fitness centers, would predict the number of tanning facilities. The number of tanning
facilities within 605 census tracts of San Diego County was examined through geographic information systems mapping. Results
from multivariate Poisson log-linear regression indicated that higher numbers or proportions of the following variables within
a census tract were significantly, positively correlated with the number of tanning facilities: fitness centers, teenagers
15–19 years, females 15–24 years, females 25–29 years, and non-Hispanic Whites. Results from additional analyses using a 1000-foot
buffer zone around each census tract boundary showed that higher relative distributions of the following variables were significantly,
positively correlated with the number of tanning facilities: high schools, fitness centers, females 15–24 years, females 25–29 years,
and non-Hispanic Whites. These findings suggest a relationship exists between the numbers of tanning facilities and certain
built-environmental and demographic characteristics within census tracts. Determining this relationship is important for developing
future interventions. 相似文献
104.
Activation of the CPP32 protease in apoptosis induced by 1-beta-D- arabinofuranosylcytosine and other DNA-damaging agents 总被引:2,自引:0,他引:2
The response of human myeloid leukemia cells to treatment with 1-beta- arabinofuranosylcytosine (ara-C) includes the induction of apoptosis. Ara-C induced apoptosis is associated with proteolytic cleavage of poly(ADP-ribose) polymerase (PARP) and protein kinase C (PKC) delta. However, the signals involved in this response are unknown. The present studies show that ara-C treatment of U-937 cells is associated with induction of a protease activity that cleaves the tetrapeptides Ac-DEVD- pNA and Ac-DMOD-pNA found at the cleavage sites of PARP and PKC delta, respectively. The ara-C-induced protease activity was sensitive to overexpression of the anti-apoptotic protein Bcl-xL and the baculovirus protein p35. By contrast, overexpression of the cowpox virus protein CrmA blocked apoptosis induced by engagement of the Fas receptor but not that induced by ara-C. CrmA overexpression also had no detectable effect on ara-C-induced cleavage of PKC delta. The results further show that ara-C induces activation of the CPP32 protease by a CrmA- insensitive and p35-sensitive mechanism. Similar results were obtained with cisplatinum, etoposide, and camptothecin. These findings indicate that ara-C and other DNA-damaging agents activate a CrmA-insensitive apoptotic pathway involving CPP32 and that these signals differ from those associated with apoptosis induced by the Fas receptor. 相似文献
105.
Severe Delayed Hemolytic Transfusion Reaction Complicating an ABO-Incompatible Bone Marrow Transplantation 总被引:2,自引:0,他引:2
Phyllis I. Warkentin Roslyn Yomtovian David Hurd Richard Brunning Jane Swanson John H. Kersey and Jeffrey McCullough 《Vox sanguinis》1983,45(1):40-47
A 26-year-old, blood group O bone marrow transplant recipient experienced a severe, delayed hemolytic transfusion reaction 6 days following transplantation of marrow from his HLA-mixed lymphocyte culture - identical, blood group AB sister. The patient's pretransplant serum contained both anti-A (IgG titer = 1:128; IgM = 1:32) and anti-B (IgG = 1:16; IgM = 1:64) which was reduced by a two-plasma volume plasma exchange followed by transfusion of four units of incompatible, donor type red cells. The patient experienced no immediate adverse reaction. On the 6th posttransplant day, he became acutely dyspneic. His hematocrit dropped to 18%; the direct antiglobulin test was positive for IgG and complement; anti-A and anti-B were eluted from his red cells. His peripheral blood smear demonstrated extensive agglutination resembling a mixed field reaction. This case demonstrates that significant morbidity may be associated with major ABO-incompatible bone marrow transplantation, that the transfusion of incompatible red cells should be undertaken with extreme caution, and that efforts should be continued to develop methods of pretransplant in vitro red cell removal from the infused bone marrow. 相似文献
106.
107.
al-Shahi R; Mason JC; Rao R; Hurd C; Thompson EM; Haskard DO; Davies KA 《Rheumatology (Oxford, England)》1997,36(7):794-798
Thrombocytopenia in patients with acute systemic lupus erythematosus (SLE)
frequently presents the clinician with considerable diagnostic and
therapeutic difficulties. In this Grand Round, we present a 48-yr- old
woman with a 7 yr history of lupus, who presented with acute proliferative
glomerulonephritis and nephrotic syndrome, pneumonia, profound
hypocomplementaemia and a severe microangiopathic haemolytic anaemia with
associated thrombocytopenia. Her thrombocytopenia proved initially
refractory to conventional immunosuppressive therapy, and corticosteroids,
and resolved only with plasma exchange and repeated fresh frozen plasma
infusions. Serological testing revealed high-titre antinuclear antibodies
(ANA) and markedly raised antibodies to double- stranded (ds) DNA, but no
significant elevation in anticardiolipin antibodies. Platelet-associated
IgG and IgM and antibodies to the CD36 glycoprotein antigen, expressed on
platelets and endothelium, were detected in the serum. We address some of
the difficult diagnostic and management issues raised by this complex
patient and the possible immunopathological links between antibodies to
CD36, immune-mediated red cell destruction, thrombocytopenia and thrombotic
microangiopathic haemolytic anaemia.
相似文献
108.
109.
Genotyping for platelet-specific antigens: techniques for the detection of single nucleotide polymorphisms 总被引:13,自引:0,他引:13
Accurate typing of patients for platelet-specific (human platelet) antigens (HPA) is required in several different clinical situations, and blood services need to maintain panels of HPA-typed apheresis platelet donors and whole-blood donors to support HPA alloimmunized patients. Six clinically relevant HPA alloantigen systems have been described and, in addition, a significant number of HPA alloantigens with a highly skewed allele frequency or of very low immunogenicity have been reported. Certain well-characterized biallelic systems such as Gov have not as yet been included in the HPA nomenclature but are included in this review. Biochemical studies have identified the platelet membrane proteins on which the HPA antigens are localized. Cloning of the genes encoding these proteins and the realization that there is adequate mRNA in fresh platelets has led to identification of the molecular basis of HPA antigens over the last decade. All but one of the biallelic platelet-specific alloantigen systems are based on a single nucleotide polymorphism in the DNA sequence, corresponding to a single amino acid substitution in the encoded primary protein sequence. The discovery of the genetic basis of the alloantigens has allowed the development of polymerase chain reaction-based techniques for HPA genotyping using genomic DNA. The genetic basis of the HPA alloantigens, the most commonly used genome typing techniques and their pitfalls, and future developments, are discussed in this review. 相似文献
110.
Evidence has been found to document the presence of circulating immune complexes in all patients with Felty's syndrome. The sera of all 12 patients studied showed intermediate complexes by analytical ultracentrifugation. The sera of 9 of 12 patients (75%) showed precipitin lines upon immunodiffusion against IgM rheumatoid factor. Both findings were statistically increased above those in a matched group of patients with classic rheumatoid arthritis. The presence of circulating immune complexes in the sera of the Felty patients was consistent with the observation that large inclusions containing IgG, IgM, and complement were phagocytized by normal polymorphonuclear cells when incubated with sera of Felty patients. Normal polymorphonuclear cells phagocytosed inclusions from 77% of Felty sera, compared with 27% classic rheumatoid arthritis sera. It is suggested that the uptake of immune complexes by polymorphonuclear cells plays a role in the neutropenia of Felty's syndrome. 相似文献