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991.
The dispensable N-terminus of iso-1-cytochrome c (iso-1) in the yeast Saccharomyces cerevisiae was replaced by 11 different amphipathic structures. Rapid degradation of the corresponding iso-1 occurred, with the degree of degradation increasing with the amphipathic moments; and this amphipathic-dependent degradation was designated ADD. ADD occurred with the holo-forms in the mitochondria but not as the apo-forms in the cytosol. The extreme mutant type degraded with a half-life of approximately 12 min, whereas the normal iso-1 was stable over hours. ADD was influenced by the +/– state and by numerous chromosomal genes. Most importantly, ADD appeared to be specifically suppressed to various extents by deletions of any of the YME1, AFG3, or RCA1 genes encoding membrane-associated mitochondrial proteases, probably because the amphipathic structures caused a stronger association with the mitochondrial inner membrane and its associated proteases. The use of ADD assisted in the differentiation of substrates of different mitochondrial degradation pathways. 相似文献
992.
蛋白转导域介导BCR/ABL抗原对CML患者T细胞的活化作用 总被引:2,自引:0,他引:2
目的:研究蛋白转导域(PTD)介导的BCR/ABL抗原对慢性髓细胞白血病(CML)患者T细胞的特异性活化作用。方法:利用基因工程技术,将PTD基因与CML b3a2 bcr/abl基因融合并原核表达。将纯化的PTD—BCR/ABL融合蛋白与CML患者外周血单个核细胞(PBMC)体外共孵育,用流式细胞仪分别检测CD4^ 、CD8^ T细胞上活化抗原CD25的表达。结果:终浓度为100mg/L的PTD—BCR/ABL抗原体外刺激4d后,10例CML患者中,5例表现为CD8^ T细胞活化,2例表现为CD4^ T细胞活化,其中有1例CD8^ 和CD4^ T细胞同时活化;而作为对照的BCR/ABL抗原刺激组无一例表现为CD8^ 或CD4^ T细胞活化。结论:PTD能将外源性BCR/ABL抗原转导入抗原呈递细胞内,加工呈递后激活抗原特异性CD8^ 及CD4^ T细胞,为CML特异性CD8^ 、CD4^ T细胞的体外活化及细胞免疫治疗开辟一条新的途径。 相似文献
993.
994.
Pregnancy following treatment of symptomatic myomas with laparoscopic bipolar coagulation of uterine vessels 总被引:7,自引:0,他引:7
Chen YJ Wang PH Yuan CC Yen YK Yang MJ Ng HT Chang SP Liu WM 《Human reproduction (Oxford, England)》2003,18(5):1077-1081
BACKGROUND: Laparoscopic bipolar coagulation of uterine vessels (LBCUV) has been employed for women with symptomatic uterine myomas, but its effect on subsequent pregnancy has not been characterized. METHODS: Four-hundred and twenty-three women entered the study between March 1999 and December 2001. Of these, 142 women (33.6%) were under the age of 40 years at the time of LBCUV, 36 of whom (36/142, 25.3%) were sexually active without contraception. In a prospective study of 142 patients (<40 years old) undergoing LBCUV for symptomatic myomas, 15 women became pregnant (17 total pregnancies) and were evaluated by physical and ultrasound examinations. RESULTS: The volume of the dominant myoma was 117.4 +/- 118.4 and 36.8 +/- 56.8 cm(3) before and after LBCUV respectively. Volume of the dominant myoma after pregnancy was 46.2 +/- 76.7 cm(3) (mean +/- SD). There was a significant difference in myoma volume before and after LBCUV (P = 0.002), but no significant difference in myoma volume when comparing post-partum size with post-LBCUV size (P = 0.269). Pregnancy outcomes included seven miscarriages in the first trimester and one premature rupture of membrane (PPROM). Although the other pregnancies were regarded as uncomplicated, only two women were delivered of normal neonates as the other seven pregnancies were terminated secondary to patient request. CONCLUSIONS: The pregnancy and term pregnancy rates in sexually active women without contraception were 41.6% (15/36) and 5.6% (2/36) respectively. Because a relatively high rate (7/17, 41.2%) of early miscarriages was observed, we recommend that this procedure be employed only for women who do not desire additional children. 相似文献
995.
The study aim was to evaluate the effect of different attentional tasks on the amplitudes and latencies of painful and non-painful contact heat evoked potentials (CHEPs). CHEPs were recorded in 12 healthy subjects during two experimental conditions, in which attention was oriented towards the intensity and the distress caused by the stimuli and were compared with CHEPs recorded during a neutral condition. The painful heat stimulation produced a negative potential at Cz vertex with a latency around 540 ms (Cz/N540), a positive peak at Cz electrode around 730 ms (Cz/P730) and, lastly, a positive peak around 1000 ms (Pz/P1000) in the Pz traces. The Cz/P730 wave was significantly higher in amplitude only during the painful stimulation and is probably related to coding the nociceptive activity. Varying the attentional target towards different properties of the stimulus did not cause any significant change in CHEP responses amplitude and latencies compared with the neutral condition. Our results suggest that CHEPs represent a reliable functional measure of the nociceptive pathways and that they are generated by the activation of different cerebral areas involved in pain processing. The high activation level of each of these area or their spatial neighbouring might explain the strong similarity of CHEP components recorded during different attentional manipulations. 相似文献
996.
997.
998.
Serum hepatitis B virus DNA in healthy HBsAg-negative Chinese adults evaluated by polymerase chain reaction 总被引:3,自引:0,他引:3
L N Shih J C Sheu J T Wang G T Huang P M Yang H S Lee J L Sung T H Wang D S Chen 《Journal of medical virology》1990,32(4):257-260
Serum hepatitis B virus (HBV) DNA was assayed using polymerase chain reaction, in 107 HBsAg-negative normal Chinese subjects. The results showed that eight subjects (7.5%) had HBV DNA. In the subgroup with antibody to hepatitis B surface antigen (anti-HBs) and to hepatitis B core antigen (anti-HBc), 7.3% (5/68) were positive for HBV DNA; HBV DNA was not detected in six individuals with anti-HBs only and in nine with anti-HBc only. In four persons with anti-HBc and anti-HBe, one had HBV DNA. In 20 subjects negative for all hepatitis B serological markers, two (10%) were found to have HBV DNA. This study indicates that serological markers are not adequate to rule out HBV infection, and it further implies that present blood donor screening methods may need improving. 相似文献
999.
Technical advances in the field of flow cytometry have made it feasible for many academic and private hospital laboratories to purchase relatively inexpensive "user friendly" flow cytometers that do not require dedicated flow cytometer operators, special rooms, or a significant amount of laboratory space. Because the financial and physical constraints in operating a flow cytometer have been substantially reduced, many pathologists may now be considering such a purchase. By chronicling the clinical activities of a single flow cytometric immunophenotyping laboratory, this report will answer a variety of questions that may be asked by pathologists regarding both the utility of flow cytometers in clinical diagnosis and the mechanics of operating an immunophenotyping laboratory. The types of tissues that can be evaluated by flow cytometry will be detailed, and we will summarize the number and type of flow cytometric clinical studies performed in our laboratory since its development in 1983. Practical aspects of laboratory operation including technical staff requirements, specimen handling and processing procedures, monoclonal antibody selection, and quality control procedures will be presented. In addition, a comprehensive review of flow cytometric immunophenotyping studies as applied to the diagnosis of leukemias, lymphomas, and immunodeficiency disorders will be presented along with case examples that illustrate our approach to the interpretation of immunophenotyping results. 相似文献
1000.
An adhesive glycoprotein from rat ascites hepatoma cells potentiates natural cytotoxic activity by rat spleen cells. 下载免费PDF全文
In a previous paper, we have described a cell-surface associated adhesive glycoprotein (AF) that has been separated and highly purified from rat ascites hepatoma AH136B cells. AF was found to induce the aggregation and adhesiveness of hepatoma cells. AF was also shown to have a mitogenic activity on rat T lymphocytes, and to stimulate them to produce a lymphokine chemotactic for macrophages. In the present paper, we have examined the effects of AF on natural killing (NK) activity by rat spleen cells against NK-sensitive YAC-1 cells using 51Cr-release cytotoxicity assay. NK activity of spleen cells was potentiated by AF treatment in a dose-dependent manner. A short incubation with AF was sufficient for the potentiation of NK activity, whereas the potentiation by OK-432, which is well known as a potentiator of anti-tumour activity, required a longer stimulation. Macrophage depletion from spleen cells resulted in the decreased potentiating effects of OK-432, whereas the depletion failed to influence the effects of AF. IN subsequent experiments, it was found that AF could potentiate NK activity of the NK-cell enriched fraction. We further found that culture supernatants from spleen cells and peritoneal exudate cells treated with OK-432 potentiate the NK activity, whereas those from AF-treated cells fail. It was thus suggested that AF acts directly on the cells responsible for NK activity, and that the mechanisms of AF-induced potentiation of NK activity differ from those of OK-432-induced potentiation. 相似文献