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排序方式: 共有662条查询结果,搜索用时 31 毫秒
51.
52.
Canthaxanthin induces apoptosis in human cancer cell lines 总被引:3,自引:1,他引:2
Palozza P; Maggiano N; Calviello G; Lanza P; Piccioni E; Ranelletti FO; Bartoli GM 《Carcinogenesis》1998,19(2):373-376
To investigate the possibility that canthaxanthin inhibits cancer cell
growth by inducing apoptosis, human WiDr colon adenocarcinoma and SK- MEL-2
melanoma cells were treated with two different doses of the carotenoid for
48 h. Canthaxanthin was incorporated and/or associated to cells. The
treatment with the carotenoid caused growth inhibition in both cell types.
Concomitantly, apoptosis was induced. Increasing time of exposure and
carotenoid concentration, this effect was more pronounced. At 48 h, the
percentages of apoptotic cells were 13 and 15, using 1 microM
canthaxanthin, and 18 and 20, using 10 microM canthaxanthin in WiDr and
SK-MEL-2 cells, respectively. This study represents the first demonstration
that canthaxanthin is able to induce apoptosis in tumour cells.
相似文献
53.
Effects of allergy and age on responses to salbutamol and ipratropium bromide in moderate asthma and chronic bronchitis. 总被引:2,自引:2,他引:0
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The bronchodilating responses to 400 micrograms salbutamol and 80 micrograms ipratropium bromide were studied in 188 patients with chronic bronchitis (n = 113) or asthma (n = 75) and mild to moderate airflow obstruction (forced expiratory volume in one second (FEV1) above 50% but below 2 SD of predicted value) in a crossover study on two days a week apart. Both the patients with asthma and the patients with chronic bronchitis varied considerably in their responses to the salbutamol and the ipratropium bromide. The mean increase in FEV1 in the subjects with asthma was higher after salbutamol (0.371 or 18% of the prebronchodilator value) than after ipratropium bromide (0.26 1 or 13%). In chronic bronchitis there was no difference between the increase in FEV1 after salbutamol (0.161 or 7%) and after ipratropium bromide (0.191 or 8%). When patients were categorised into those with a better response to salbutamol 400 micrograms and those with a better response to ipratropium bromide 80 micrograms, patients with chronic bronchitis responded better in general to ipratropium bromide whereas asthmatic patients responded better to salbutamol. The response pattern was also related to allergy and age, allergic patients and patients under 60 being more likely to respond better to salbutamol 400 micrograms than non-allergic patients and older patients, who benefited more from ipratropium bromide 80 micrograms. The response pattern was not related to sex, smoking habits, lung function, bronchial reactivity, respiratory symptoms, or number of exacerbations during the preceding year. 相似文献
54.
应用灰关联分析及信息处理方法评价骨质疏松症复方中药治疗的用药规律 总被引:1,自引:0,他引:1
学术背景:中医药在防治骨质疏松症方面具有独特优势,但目前关于该病的中药复方用药规律的研究较少,而且多以统计用药频率为主。此法往往需要大样本且须具有典型的概率分布。此外,在中医诊治过程中,个人经验也造成处方配伍用药的偏倚,药物剂量相距甚远,这使药物治疗的安全性和有效性难以保证。目的:应用灰关联分析及信息处理方法探讨治疗骨质疏松症的用药规律。
检索策略:由第一、三、四作者应用计算机检索中国知网1995-01/2005-12期间的相关文献。所用中文检索词包括“骨质疏松,骨萎,中药,治疗”。共检索到169篇文献。纳入标准:①治疗方法为单纯使用中药治疗,不包括其他辅助治疗,如西药、手法、针灸等。②所有中药复方必须药味完整,剂量准确,主治明确,疗效确切。排除标准:排除含有辅助治疗及疗效不确切,药味不全、没有给出药物剂量或剂量不准确的文献。结果选出104篇符合标准的文章。
文献评价:文献的来源主要是通过对治疗骨质疏松症的中药复方的相关文章进行循证医学系统查询,通过灰关联分析及信息处理方法分析查询结果,以此探讨治疗骨质疏松症的中药复方用药规律。资料综合:在治疗骨质疏松症的104首中药复方中共使用106种药物1204频次。其中,使用频次在10次以上的依次为熟地、淫洋藿、杜仲等34味中药,使用总频次为890次,灰关联系数大小依次为山药、淫羊藿、骨碎补等。性温、平,味甘、苦、辛,归肾经、肝经和脾经的药物所占比例较大。在药物分类中,补益药达到23种,占总数的67.6%。其中,又以补阳药为主,其次为补气药。
结论:灰关联分析及信息处理结果认为骨质疏松症的主要病理是脾肾阳虚,其次为气虚、阴虚和血虚,在用药中主要使用补益肝肾、补脾益气、滋阴活血药。 相似文献
55.
Mixed lymphocyte reactivity and cell-mediated lympholysis to trinitrophenyl-modified autologous lymphocytes in C57BL/10 congenic and B10.A recombinant mouse strains
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GM Shearer EC Lozner TG Rehn A Schmitt-Verhulst 《The Journal of experimental medicine》1975,141(4):930-934
Cell-mediated lympholysis (CML) to trinitrophenyl (TNP)-modified autologous splenic lymphocytes has been recently reported in the mouse (1). Both the sensitization and effector phases of this phenomenon were shown to be T-cell mediated. Effector cell specificity studies indicated that modification of the target cells is a necessary but insufficient requirement for cytolysis, and suggested that altered cell surface components controlled by genes mapping in the mouse major histocompatibility H-2 complex (MHC) are important in the specificity of the cytotoxic reaction (1). In allogeneic models the generation of cytotoxic effector cells has been shown to be preceded or accompanied by immunogen- induced proliferation of responding lymphocytes, i.e. a mixed lymphocyte reaction (MLR) (2-5), although the generation of effectors may not necessarily always be the consequence of extensive cell proliferation (5). If the induction of cytotoxic effector lymphocytes by modified syngeneic spleen cells is characteristic of sensitization with cellular alloantigens, one would expect to find that sensitization with TNP-modified autologous cells would also induce thymidine incorporation by the responding cells in the culture. The present report demonstrates that both stimulation of thymidine incorporation and generation of cytotoxic effector cells are part of the in vitro response to TNP-modified autologous lymphocytes. However, the MLR to TNP- modified autologous cells consistently appeared to be less pronounced when compared with an allogeneic MLR, whereas the cytotoxic activity of the effector cells generated by sensitization against TNP-modified autologous cells was frequently as high as that detected against H-2 alloantigens. These two components of reactivity to “modified self” are verified in several C57BL/10 congenic and B10.A recombinant mouse strains. 相似文献
56.
H-2-restricted cytotoxic effectors generated in vitro by the addition of trinitrophenyl-conjugated soluble proteins 总被引:3,自引:3,他引:3
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A Schmitt-Verhulst CB Pettinelli PA Henkart JK Lunney GM Shearer 《The Journal of experimental medicine》1978,147(2):352-368
Murine spleen cells from normal donors were cultured in vitro with trinitrobenzene sulfonate (TNBS)-conjugated soluble proteins, i.e., bovine gamma globulin (TNP-BGG) or bovine serum albumin (TNP-BSA). Addition of 100 μg of any of these TNP-proteins to the spleen cell cultures led to the generation of cytotoxic T-cell effectors which were H-2-restricted and TNP- specific. The lytic potential of such effectors was comparable to that generated by sensitization with TNBS-modified syngeneic cells, and was restricted to haplotypes shared at the K or K plus I-A, or the D regions of the H-2 complex. Greater effecter cell activity was generated by addition of TNP-BGG against TNBS-modified targets which shared K plus I-A than against modified targets which shared the D region with the responding cells, which suggests that the same immune response genes are involved when the response is generated by the addition of TNP-conjugated soluble proteins or of TNBS- modified cells. H-2-restricted, TNP-specific effecter cells were generated by culturing mouse spleen cells with syngeneic cells which had been preincubated with TNP- BGG or TNP-BSA for 1.5 h. The addition of unconjugated soluble proteins to the cultures did not result in cytotoxic effectors detectable on H-2-matched targets, whether the targets were prepared by modification with TNBS, or by incubation with either the unconjugated or TNP-conjugated proteins. Depletion of phagocytic cells in the tumor preparation by Sephadex G-10 column fractionation before incubation with TNP-BSA had no effect on their lysis by the relevant effector cells. Immunofluorescent staining of tumor target cells with anti-TNP antibodies indicated that TNP could be detected on the tumor cells within 10 rain of incubation with TNP-BSA. The cytotoxic response generated by addition of the TNP-proteins to spleen cell cultures was found to be T-cell dependent at the effector phase, as shown by the sensitivity of the lytic phase to absorbed RAMB and complement. Furthermore, the response did not appear to be attributable to antibody-dependent cellular cytotoxicity. Three mechanisms were considered which could account for the generation of H-2-restricted, TNP-specific, cytotoxic T-cell effectors by the addition of soluble TNP-proteins. These include covalent linkage of activated TNP groups from the soluble proteins to cell surface components, macrophage processing of the soluble conjugates and presentation to the responding lymphocytes in association with H-2-coded self structures, or hydrophobic interaction of the TNP-proteins to cell surfaces. Results obtained from sodium dodecyl sulfate gel patterns indicating that cell-bound TNP was still linked to BSA, and the observation that phagocytic-depleted cells could interact with the soluble TNP-proteins and function as H-2-restricted targets, appear not to favor the first two proposed mechanisms. 相似文献
57.
Familial hemiplegic migraine: a clinical comparison of families linked and unlinked to chromosome 19 总被引:5,自引:0,他引:5
GM Terwindt RA Ophoff J Haan RR Frants MD Ferrari for the DMGRG 《Cephalalgia : an international journal of headache》1996,16(3):153-155
We compared the clinical characteristics of 50 patients from three unrelated families with familial hemiplegic migraine (FHM) linked to chromosome 19, with those of 20 patients from two families with FHM not linked to chromosome 19. We found no significant differences for age at onset, frequency and duration of attacks, duration of the paresis, and occurrence of basilar migraine symptoms. In the linked families, significantly more patients reported unconsciousness during attacks (39%, vs 15%; p<0.05) and provocation of attacks by mild head trauma (70% vs 40%; p< 0.05). In one linked family patients also displayed chronic progressive cerebellar ataxia, whereas in one unlinked family benign infantile convulsions occurred in addition to FHM. Interestingly, so far an association with cerebellar ataxia was only described in chromosome 19-linked families. FHM linked to chromosome 19 and FHM unlinked to chromosome 19 do not differ with respect to clinical features. 相似文献
58.
59.
Specificity of cytotoxic effector cells directed against trinitrobenzene sulfonate-modified syngeneic cells. Failure to recognize cell surface- bound trinitrophenyl dextran
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PA Henkart A Schmitt-Verhulst GM Shearer 《The Journal of experimental medicine》1977,146(4):1068-1078
Mouse splenic lymphocytes and lymphoid tumor cells were modified with the trinitrophenyl (TNP) group either by treatment with trinitrobenzene sulfonate (TNBS) (which covalently modifies cell surface proteins) or with TNP stearoyl dextran (TSD) (which binds to the cell by noncovalent forces). These cell preparations were compared for their ability to: (a) sensitive syngeneic splenic lymphocytes leading to the generation of cytotoxic effector cells; (b) serve as lysable targets in a 4-h(51)Cr- release assay for effector cells generated in (a); and (c) act as blocking cells in the lysis of TNBS-medified targets lysed by TNP self effector cells generated in (a). In none of these three experimental systems did TSD-medified syngeneic spleen or H-2-matched tumor cells act either as a sensitizing immunogen or as a target antigen, despite the demonstration that quantitatively equivalent mounts of TNP were exposed on the cell surface in the TNBS- and TSD-modified cells. In contrast, TNBS-modified spleen cells sensitized syngeneic lymphocytes to generate effectors against TNBS-modified syageneic targets. Furthermore, TNBS- modified, H-2-matched cells served as specific lysable targets and as inhibiting cells for such effectors. These results indicate that the manner in which TNP is associated with the cell surface is important in the immunogenicity and antigenicity of hapten-modified syngeneic stimulating cells in generating H-2-associated cell-mediated lympholysis (CML) reactions. These findings raise the possibility that a covalent or at least a stable linkage with cell surface proteins (possibly H-2- controlled products) is important for immunological function. Furthermore, these observations do not favor the dual receptor model for H-2-restricted syngeneic CML if it is assumed in such a model that one receptor is specific for the TNP moiety and the second for unmodified self major histocompatibility products. 相似文献
60.
The present criteria for confirmation of human T-lymphotrophic virus types I and II (HTLV-I/II) infection in blood donors are based on seroreactivity to p24 (gag) and gp46 and/or gp61 (env) on Western blot (WB) and radioimmunoprecipitation assays (WB/RIPA). Any single band and other combinations are classified as indeterminate. This case report documents infection in a donor with a repeatedly indeterminate pattern. The blood donor was anti-HTLV-I/II positive on enzyme-linked immunoassay, and two sera taken 5 years apart were WB/RIPA-indeterminate (p19 and gp68 only). His donations in the interval were associated with transmission of HTLV-I to four of the six recipients available for study. Other recipients of blood from donors whose WB/RIPA results were indeterminate by present criteria should be examined to determine if additional patterns are at least occasionally associated with transmission. The likelihood that such donors are infected is important to those who are counseling them and making decisions concerning recipients of their bloody. 相似文献