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81.
p53蛋白的免疫亲和层析纯化 总被引:2,自引:0,他引:2
建立了p53单克隆抗体pAb1801的免疫亲和层极法纯化p53蛋白,所纯化的p53蛋白经Western Blot(ECL法)检测证明:用此法从p53阳性的SW480细胞中分离到p53蛋白。银染显示pH2.0甘氨酸缓冲液比pH2.8的甘氨酸缓冲液洗脱效果好,这种方法的建立将为分离肿瘤细胞中引起p53蛋白功能失活和研究肿瘤发生机制提供一种有效途径。 相似文献
82.
Human mini-chromosomes in mouse embryonal stem cells 总被引:3,自引:2,他引:3
We have introduced human mini-chromosomes of 4 Mb and approximately 15 Mb
in size into mouse embryonal stem cells. Although these human mini-
chromosomes are stable in hamster and chicken cells, they re-arrange or
segregate aberrantly in the embryonal stem cells and are rapidly lost in
the absence of selection. However, one of the mini-chromosomes re-
arranged, acquired mouse centromeric sequences and was then stably
maintained for at least 60 population doublings in culture. This mini-
chromosome, which is 4 Mb in size, is a candidate for a mouse germ line
chromosome vector.
相似文献
83.
Determination of the parent of origin in nine cases of prenatally detected chromosome aberrations found after intracytoplasmic sperm injection 总被引:1,自引:17,他引:1
Van Opstal D; Los FJ; Ramlakhan S; Van Hemel JO; Van Den Ouweland AM; Brandenburg H; Pieters MH; Verhoeff A; Vermeer MC; Dhont M; In't Veld PA 《Human reproduction (Oxford, England)》1997,12(4):682-686
Prenatal cytogenetic analysis of 71 fetuses conceived by intracytoplasmic
sperm injection (ICSI) resulted in the detection of nine (12.7%) chromosome
aberrations including two cases of 47,XXY, four cases involving a 45,X cell
line and three autosomal trisomies. Molecular analysis of the parental
origin of the deleted or supernumerary chromosome was performed by using
polymorphic microsatellite markers. Six cases involving a sex chromosome
abnormality were found to be of paternal origin while the two trisomic
cases that could be analysed were of maternal origin. Two cases involved
the same infertile couple who had two consecutive ICSI pregnancies
terminated because of a chromosome abnormality. The replaced embryos in
both cases originated from a single batch of ICSI fertilized oocytes of
which part was used to initiate the first pregnancy and part was
cryopreserved and used to initiate the second pregnancy.
相似文献
84.
Difference in cell binding patterns of two monoclonal antibodies recognizing distinct epitopes on a human melanoma-associated oncofetal antigen 总被引:1,自引:0,他引:1
Two monoclonal antibodies (MAbs), 140.240 and 96.5, generated independently in different laboratories, have been shown to detect the target structures of 87,000 (gp87) and 97,000 (p97) glycoproteins, respectively, both strongly expressed by melanoma cells and fetal small intestine. To determine whether MAb 140.240 and MAb 696.5 recognized a same target structure, they were tested in immunoprecipitation/SDS-PAGE using NP-40 lysates of melanoma cells labelled with [35S]methionine for 18 hr. Both antibodies precipitated a single band with Mr = 87,000. Reciprocal immunodepletion studies showed that neither of the two antibodies detected the 87,000 band in the lysate immuno depleted by either antibody, suggesting that these two antibodies recognize the same or extremely similar molecules. Two-dimensional tryptic peptide mapping analysis showed that the two identified molecules shared the same finger-printing pattern. A 40,000 fragment of the 87,000 molecule produced by protease digestion was precipitated by MAb 96.5 but not MAb 140.240, indicating that the epitopes recognized by the two antibodies are localized at discrete sites on the molecule. Serological studies on these two antibodies revealed slightly different binding patterns in the MAb 140.240 exhibited a more melanoma-restricted specificity, while MAb 96.5 had a specificity to melanoma and to some other cell types. The observed difference in epitope specificity may be important in the clinical applications of these antibodies. 相似文献
85.
Lam GK Liao HX Xue Y Alam SM Scearce RM Kaufman RE Sempowski GD Haynes BF 《Journal of clinical immunology》2005,25(1):41-49
CD7 is an immunoglobulin superfamily molecule expressed on T, NK, and pre-B lymphocytes. Previous studies have demonstrated a role for CD7 in T- and NK-cell activation and cytokine production. Recently, an epithelial cell secreted protein, K12, was identified as a CD7 ligand. Although CD7 is expressed intrathymically, it is not known if K12 is produced in human thymus. To determine roles that K12 might play in the human thymus, we analyzed expression of K12 in human thymocytes, thymic epithelial cells (TE), and thymic fibroblasts. We found that recombinant human K12 bound strongly to soluble hCD7, with a Keq of 37.6×10–9M, and this interaction was inhibited by a novel antihuman K12 monoclonal antibody (K12-A1). K12 mRNA was detected by RT–PCR and northern analysis in human TE and thymic fibroblasts, but not in human thymocytes. Expression of K12 in TE cells was upregulated by IFN- . Taken together, these data demonstrated that K12 is produced by human TE cells and thymic fibroblasts, and is regulated in thymus by IFN- . These data suggest a role for thymic microenvironment-produced K12 in regulation of thymocyte signaling and cytokine release, particularly in the setting of thymus pathology where IFN- is upregulated such as myasthenia gravis. 相似文献
86.
Yongchol Shin Atsushi Kitayama Tetsuya Koide Daniel A Peiffer Makoto Mochii Arnold Liao Naoto Ueno Ken W Y Cho 《Developmental dynamics》2005,232(2):432-444
To isolate novel genes regulating neural induction, we used a DNA microarray approach. As neural induction is thought to occur by means of the inhibition of bone morphogenetic protein (BMP) signaling, BMP signaling was inhibited in ectodermal cells by overexpression of a dominant-negative receptor. RNAs were isolated from control animal cap explants and from dominant-negative BMP receptor expressing animal caps and subjected to a microarray experiment using newly generated high-density Xenopus DNA microarray chips representing over 17,000 unigenes. We have identified 77 genes that are induced in animal caps after inhibition of BMP signaling, and all of these genes were subjected to whole-mount in situ hybridization analysis. Thirty-two genes showed specific expression in neural tissues. Of the 32, 14 genes have never been linked to neural induction. Two genes that are highly induced by BMP inhibition are inhibitors of Wnt signaling, suggesting that a key step in neural induction is to produce Wnt antagonists to promote anterior neural plate development. Our current analysis also proves that a microarray approach is useful in identifying novel candidate factors involved in neural induction and patterning. 相似文献
87.
88.
细胞周期蛋白E对乳腺癌细胞MCF-7生长及周期相关基因的影响 总被引:3,自引:1,他引:3
观察细胞周期蛋白(cyclin)E的表达对乳腺癌细胞MCF-7生长及其他周期相关基因的影响。方法构建正义和反义cyclin E cDNA真核表达载体,并采用lipofect AMINE转染,将其导入MCF-7细胞,获得稳定表达正义及反义cyclinE的细胞系,经Southern和Western blot检测有外源性片片段的插入及表达,并作细胞生长曲线、四甲偶氮唑盐(MTT)法和流式细胞计数分析;用 相似文献
89.
Min-Nan Hung Shey-Ying Chen Jiun-Ling Wang Shan-Chwen Chang Po-Ren Hsueh Chun-Hsing Liao Yee-Chun Chen 《Journal of microbiology, immunology, and infection》2005,38(6):436-443
A prospective observational study was conducted to evaluate the clinical characteristics and outcome of community-acquired anaerobic bacteremia. From June 1 2001 through May 31 2002, 52 patients with community-acquired anaerobic bacteremia were enrolled at the emergency department in a teaching hospital. There were 19 patients (34%) with polymicrobial bacteremia and Escherichia coli was the most common copathogen (n = 6). Of 62 anaerobic isolates, species of the Bacteroides fragilis group were the most common isolates (n = 28, 45%), followed by Clostridium spp. (n = 11, 18%). Among the 52 patients enrolled, up to 27% had underlying malignancy and the gastrointestinal tract accounted for 48% of the sources of infection. Clinical manifestations suggesting anaerobic infections were common and three-quarters (n = 39) of 52 patients received adequate empirical antimicrobial treatment. Documentation of anaerobic bacteremia seldom influenced antimicrobial treatment. The 30-day mortality was 25%. Although univariate analysis revealed that underlying malignancy (p=0.003), leukopenia (p=0.044) and absence of fever (p=0.047) were associated with mortality, only malignancy (p=0.007) was an independent risk factor in the multivariate analysis. 相似文献
90.
At the University of California, Irvine Medical Center, an end-of-life curriculum was implemented in 2000 for an internal medicine residency utilizing a longitudinal approach that allowed residents to follow patients through their entire hospice experience. An elective home hospice rotation was developed for which third-year residents served as primary care physicians for patients at the end of life over a one-year period. Residents were supervised by faculty who were hospice medical directors. They also learned through case vignettes, quarterly meetings, textbook reading, and personal projects. From July 2000 to June 2002, residents demonstrated positive attitudes towards hospice care and recommended the rotation highly (mean 8.86 on a scale of 1-10). The rotation grew in popularity from six initial residents to ten residents the next year, and has since become a mandatory rotation for all senior residents. A 360-degree evaluation uniformly indicated positive resident performance from the hospice team (mean scores 7.56-8.69 on a 1-9 scale), family (mean scores 9.3-9.7 on a 1-10 scale) and faculty (mean scores 7.29-7.72 on a 1-9 scale). Residents were also pleased with the level of teaching (mean 8.86 on a scale of 1-10) and felt that the patient care load was "just right." Their knowledge improved by 8% (p =.0175). In conclusion, a longitudinal hospice rotation was implemented that fulfilled curricular goals without undue burden on the residents or residency program. 相似文献