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101.
生物软组织可视为具有多层次结构的织构复合水凝胶体系(TCHS)、以水凝胶复合元件(HCE)为基本的构件(CP),通过一定的组合、排列方式构筑一系列多层次结构的不同软组织。软组织中任何层次的结构单元既可视为织构复合水凝胶体系又可视为构件。任何层次的TCHS中,构件的结构及其组合排列方式决定着该层次单元的功能。以织构复合水凝胶体系的观点考察了真核细胞、角膜和骨骼肌的多层次结构。双层网络水凝胶、皮芯复合水凝胶纤维人工肌肉模型、时空匹配可降解细胞支架等研究成果初步地证明了提出织构复合水凝胶体系观点的合理性。 相似文献
102.
Production of hypoprothrombinemia by moxalactam and 1-methyl-5-thiotetrazole in rats 总被引:2,自引:4,他引:2 下载免费PDF全文
To determine whether the hypoprothrombinemia associated with antibiotics containing a 1-methyl-5-thiotetrazole (MTT) group is a result of the presence of the MTT group, rats were maintained on a vitamin K-deficient diet for 10 days and then received either intravenous moxalactam or cefotaxime or oral MTT for two additional days. MTT and moxalactam, which contains the MTT group, prolonged prothrombin time. Cefotaxime, which lacks the MTT group, had no effect. 相似文献
103.
H Liang Y Nishioka C F Reich D S Pisetsky P E Lipsky 《The Journal of clinical investigation》1996,98(5):1119-1129
To investigate the potential of DNA to elicit immune responses in man, we examined the capacity of a variety of oligodeoxynucleotides (ODNs) to stimulate highly purified T cell-depleted human peripheral blood B cells. Among 47 ODNs of various sequences tested, 12 phosphorothioate oligodeoxynucleotides (sODNs) induced marked B cell proliferation and Ig production. IL-2 augmented both proliferation and production of IgM, IgG, and IgA, as well as IgM anti-DNA antibodies, but was not necessary for B cell stimulation. Similarly, T cells enhanced stimulation, but were not necessary for B cell activation. After stimulation with the active sODNs, more than 95% of B cells expressed CD25 and CD86. In addition, B cells stimulated with sODNs expressed all six of the major immunoglobulin VH gene families. These results indicate that the human B cell response to sODN is polyclonal. Active sODN coupled to Sepharose beads stimulated B cells as effectively as the free sODN, suggesting that stimulation resulted from engagement of surface receptors. These data indicate that sODNs can directly induce polyclonal activation of human B cells in a T cell-independent manner by engaging as yet unknown B cell surface receptors. 相似文献
104.
The pharmacology of a new pasteurized factor VIII (FVIII) concentrate derived from human blood plasma was studied in 23 adults with hemophilia A. In Part 1 of the study involving six nonbleeding subjects, the mean increase in FVIII activity was 1.43 +/- 0.34 U per ml 10 minutes after an intravenous dose of 50 U per kg. The intravascular survival kinetics in these six patients showed a biphasic decay curve with an initial mean half-life of 5.1 +/- 1.2 hours probably representing early redistribution, and a late half-life of 13.3 +/- 4.9 hours. In Part 2 of the study, the activity at 10 minutes was measured in another 17 patients, as well as in one patient already studied in Part 1. The mean increase in activity with the 24 observations was 1.13 +/- 0.37 U per ml with a mean FVIII dosage of 51.0 +/- 2.6 U per kg of body weight. Only one patient had an allergic reaction, which did not recur when the patient was given a second lot. 相似文献
105.
Percutaneous umbilical blood samples (PUBS), obtained under ultrasound guidance, are used for prenatal diagnosis and management of hemolytic disease of the newborn (HDN) and other fetal disorders. Rapid testing at the time of sampling is vital to distinguish fetal from maternal blood. Blood typing was performed by slide technique in the treatment room during 38 procedures on 25 patients. Anti-I was used to test 50 presumed PUBS; venous I-positive maternal blood was tested in parallel. Because anti-I cannot detect fetal blood after umbilical vein transfusion (UVT) of I-positive donor blood, ABO and Rh blood typing reagents were used to test 29 samples when maternal and fetal or donor blood groups differed. Monoclonal reagents were used for optimal detection of weak AB antigens in fetal blood. Avid, chemically modified anti-D was used for Rh typing. Blood typing showed 27 (34%) of 79 samples to be maternal blood. Fetal blood was obtained in 8 of 10 cases investigated for fetal disorder and in 16 cases of potential HDN (anti-D, 5; -CD, 5; -cE, 2; -K, 2; -c; -E). The absence of HDN (antigen-negative fetus) was determined in 4 cases. UVT afforded live birth of 9 of 10 infants with HDN and was not indicated in two cases. 相似文献
106.
107.
Thomas Dörner Annett M. Jacobi Peter E. Lipsky 《Journal of immunological methods》2011,363(2):187-197
The prototypic autoimmune disease, SLE, is known to be associated with polyclonal B cell hyperreactivity. Developing an understanding of the complex nature of human B cell differentiation, largely through the application of multiparameter flow cytometry to an analysis of circulating B cells has permitted an assessment of whether specific stages of B cell maturation are affected by the tendency for polyclonal B cell activation. Moreover, the analysis of perturbations of the specific stages of B cell maturation has generated new information on whether abnormalities in B cell differentiation are primarily involved in autoimmune disease immunopathology or, rather, are secondary to the inflammatory environment characteristic of subjects with this autoimmune disease. Multivariant analysis has begun to document abnormalities in B cell maturation that are primarily associated with lupus, or, alternatively related to disease duration, disease activity and concomitant medication. Together, these analyses have provided new insights on the role of B cell over-reactivity in SLE. 相似文献
108.
Patients with chronic inflammatory rheumatic diseases, such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and especially primary Sj?gren's syndrome (SS), are at higher risk than the general population of developing B-cell non-Hodgkin lymphoma (NHL). Analyses of the association between various lymphoma subtypes and specific disease entities suggest that this association might be mediated by disease-specific mechanisms, as well as by mechanisms unique to lymphoma subtype. These specific associations can provide important information about abnormal B-cell stimulation in these conditions. Patients with primary SS, SLE and RA are at high risk of developing diffuse large B-cell lymphomas, a group of high-grade NHLs with remarkable heterogeneity. Patients with primary SS are at particularly high risk of developing marginal-zone B-cell lymphomas. The risk factors of lymphoma development in primary SS seem to be closely related to the underlying mechanisms of abnormal stimulation and/or impaired censoring mechanisms of B cells. In patients with RA and SLE, more intense disease activity and/or long-lasting disease might be indications of a higher risk of lymphoma development. This Review will focus on the risk of lymphoma, common and disease-specific mechanisms of B-cell lymphoma development, and on the clinical consequences of lymphoma in patients with inflammatory rheumatic diseases. 相似文献
109.
OBJECTIVES: This study examined risk factors and ethnic differences in the relationship between intimate partner violence and unmet need for mental health treatment (perceived need for but did not receive treatment) in the general population. METHODS: The 2002 National Survey on Drug Use and Health was used; the analysis presented here included black, Hispanic, and non-Hispanic white women ages 18 to 49 who were cohabiting (N=7,924). Logistic regression was used to calculate adjusted odds ratios (AORs) and 95% confidence intervals (CIs). RESULTS: Victims of partner violence were twice as likely as nonvictims (AOR=2.11, CI=1.41-3.16) overall to report unmet need, after analyses controlled for socioeconomic factors and substance abuse. In ethnic-specific models, only Hispanic and non-Hispanic white women who experienced partner violence were more likely than their nonabused counterparts to report unmet need for treatment (AOR 4.11, CI=1.34-12.60, and AOR=2.12, CI=1.34-3.35, respectively). CONCLUSIONS: This study suggests that women who experienced partner violence, especially Hispanic women, are at increased risk of not receiving needed mental health care. These findings highlight the need for culturally sensitive and specific outreach about the effects of partner violence on women's mental health and how to access these services. 相似文献
110.
Gabor G. Illei Yuko Shirota Cheryl H. Yarboro Jimmy Daruwalla Edward Tackey Kazuki Takada Thomas Fleisher James E. Balow Peter E. Lipsky 《Arthritis \u0026amp; Rheumatology》2010,62(2):542-552