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排序方式: 共有1053条查询结果,搜索用时 15 毫秒
1.
目的 了解含 β-神经生长因子 (β- NGF)基因的表达质粒 PSVCEP NGF- CAT在培养肌母细胞中的表达及 L ipofect AMINE阳离子脂质体介导的转染效率。方法 将表达质粒 PSVCEP NGF- CAT经 L ipofectAMINE转染至培养成的肌母细胞中 ,用免疫细胞化学方法检测基因在肌母细胞内的表达。结果 培养肌母细胞在转染 6小时吞噬脂质体最显著 ,转染 48小时后约 40 %的肌母细胞胞质内有β- NGF基因表达。结论 含β- NGF基因的表达质粒 PSVCEP NGF- CAT可以在培养肌母细胞中表达 ,脂质体转染的方法简便、有效 相似文献
2.
Mahnaz Fatahzadeh Lida Radfar David A Sirois 《Quintessence international, dental digest》2006,37(10):777-787
Dental management of patients with autoimmune vesiculobullous disorders is complicated because of prominent involvement of oral mucosa, increased risk of oral disease, and difficulty in rendering dental care. Although these diseases are relatively uncommon, dental practitioners should be familiar with the oral sequelae of these conditions and their management. Pemphigus vulgaris, cicatricial pemphigoid, and epidermolysis bullosa represent the most common autoimmune oral vesiculobullous diseases. This case-illustrated review summarizes the pathogenesis, diagnostic features, and natural history of oral vesiculobullous disorders, placing an emphasis on the treatment and prevention of associated oral disease aimed at maintaining a healthy, functional dentition. 相似文献
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K Ungar 《Human & experimental toxicology》1992,11(3):151-154
The dissemination of information about methods in in-vitro toxicology is subject to a number of constraints which are identified and discussed, as are the ways in which INVITTOX seeks to address these problems. The continued interest of scientists in INVITTOX suggests that a real gap in information provision is being filled. 相似文献
5.
Parietal cell surface reactive autoantibody in pernicious anaemia demonstrated by indirect membrane immunofluorescence. 总被引:1,自引:4,他引:1 下载免费PDF全文
We examined, in a 'double blind' study, 60 sera from patients with pernicious anaemia for immunofluorescence reactivity with the surface membranes of viable parietal cells isolated from dog stomachs. Fifty-three sera (88%) gave an IgG autoantibody reaction with the surface membranes of parietal cells. Surface staining was also seen with parietal cells from monkey, pig, rat and mouse. The parietal cell surface reactive autoantibody was not found in any of 14 sera from patients with chronic active hepatitis, 10 from patients with systemic lupus erythematosus and 50 from healthy persons. The surface reactivity autoantibody was present in 13 of 14 sera without parietal cell microsomal antibody, 28 of 31 sera without intrinsic factor antibody and in four of four sera without microsomal and intrinsic factor antibodies. Absorption with parietal cell enriched gastric mucosal cells neutralized the activity of the surface reactive but not the microsomal antibody and cross absorption with gastric microsomes neutralized the activity of the microsomal but not the surface reactive antibody. Surface staining of parietal cells was not abolished by absorption with dog or rat hepatocytes, dog or rat kidney cells, human fibroblasts or human AB red blood cells. The results suggest that the parietal cell surface reactive antibody is probably different from the microsomal antibody. Immune reactions of the cell surface reactive antibody with parietal cell surface antigens may play a role in the pathogenesis of the gastric lesion in pernicious anaemia. 相似文献
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Quantification of specific antibody response to Cryptosporidium antigens by laser densitometry. 总被引:9,自引:9,他引:9 下载免费PDF全文
Cryptosporidium spp. is a protozoan parasite with worldwide distribution associated with diarrhea in immunocompromised patients (particularly those with acquired immunodeficiency syndrome [AIDS]) and in immunocompetent humans. Immunoglobulin M (IgM) and IgG antibody responses are readily detected by an enzyme-linked immunosorbent assay. To determine which Cryptosporidium antigens invoke antibody responses in humans, we performed polyacrylamide gel electrophoresis using purified oocysts, followed by Western blots with human sera from various populations. Of 40 sera from persons with cryptosporidiosis (24 AIDS and 16 non-AIDS patients), in 37 (93%) a 23,000-dalton antigen measured quantitatively by laser densitometry was recognized. Of 63 sera from IgM- or IgG-positive individuals, as determined by enzyme-linked immunosorbent assay, in 58 (92%) this same antigen was recognized. Up to three additional bands between 125,000 and 175,000 daltons were identified by some of these sera. These results suggest that most persons infected with Cryptosporidium spp. produce antibodies which recognize at least one common low-molecular-weight antigen. Isolation of this antigen will be useful in development of diagnostic tests and may be important in the study of immunity. 相似文献
8.
Lida Bruni Barbara Angeletti Esterina Pascale Maria Cristina Tozzi Paola Giammaria Roberto Verna Ettore D'Ambrosio 《Clinical genetics》1996,50(2):89-92
Genotyping with flanking DNA markers was used to ascertain Treacher Collins Franceschetti syndrome (TCOF1) in a subject affected by tetralogy of Fallot and cryptorchidism. The proband's family consisted of a father and sister who were affected by the disease, and a healthy mother. Since cardiac malformation and cryptorchidism have been associated with the TCOF1 syndrome, the proband was suspected to be a carrier of the mutated gene. Microsatellite markers D5S527, SPARC and D5S519, which previously mapped the TCOF1 gene within a 2.1-cM interval on chromosome 5 (5q32–33.1), were used to follow the transmission of the TCOf 1 mutated locus. Flanking markers D5S519 and D5S527 were informative and enabled us to exclude inheritance of a TCOF1 mutation to the proband, while showing that cardiac malformation and cryptorchidism were unrelated in mis patient. 相似文献
9.
Jan Höltge Linda Theron Richard G. Cowden Kaymarlin Govender Sally I. Maximo Jennifer S. Carranza Bhumika Kapoor Aakanksha Tomar Angelique van Rensburg Shuang Lu Hongwei Hu Valeria Cavioni Alessia Agliati Ilaria Grazzani Yoel Smedema Gunjanpreet Kaur Kingsley G. Hurlington Jackie Sanders Michael Ungar 《The Journal of adolescent health》2021,68(3):580-588
PurposeIn situations of adversity, young people draw on individual, relational, and contextual (community and cultural) resources to foster their resilience. Recent literature defines resilience as a capacity that is underpinned by a network of interrelated resources. Although empirical studies show evidence of the value of a network approach, little is known regarding how different country contexts influence which resources are most critical within a resource network and how resources interact for adolescent resilience.MethodsNetwork analysis was conducted with data from studies that had used the Child and Youth Resilience Measure. Regularized partial correlation networks of 17 resources were estimated for 14 countries (Botswana, Canada, China, Colombia, Equatorial Guinea, India, Indonesia, Italy, Jordan, New Zealand, the Philippines, Romania, South Africa, and Syrian refugees living in Jordan). The sample size was 18,914 (mean age = 15.70 years, 48.8% female).ResultsWe observed mostly positive associations between the resources of interest. The salience and strength of associations between resources varied by country. The most central resource across countries was having supportive caregivers during stressful times because this resource had the most and strongest positive associations with other resources.ConclusionsThis study gives first empirical evidence from multiple countries that an interplay of social–ecological resources (such as individual skills, peer, caregiver and community support, and educational aspirations and opportunities) matter for adolescent resilience. Across countries, caregiver support appears to be most central for adolescent resilience. Future resilience interventions might apply this network approach to identify important, contextually relevant resources that likely foster additional resources. 相似文献
10.
P S Ungar R F Kay 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(12):5479-5481
European Miocene "apes" have been known for nearly a century and a half but their phylogenetic significance is only now becoming apparent with the recent discovery of many relatively complete remains. Some appear to be close in time and morphology to the last common ancestor of modern great apes and humans. The current study is an attempt to reconstruct the diets of these fossils on the basis of quantitative data. Results suggest that these primates varied more greatly in their diets than modern apes, with adaptations ranging from hard-object feeding to soft-object frugivory to folivory. 相似文献