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21.
Christine Ceci 《Nursing philosophy》2003,4(1):61-76
Abstract The paper contrasts understandings of knowledge grounded in Enlightenment norms with the departures from those norms taken by some strands of feminism and hermeneutics, as well as the contributions made by the writing of Michel Foucault. A reading of Foucault's writings on knowledge, power and the discursive constitution of self and world is offered as a potentially useful frame within which to raise questions about nursing, nurses and knowledge. 相似文献
22.
Effects of basic fibroblast growth factor on biological characteristics of osteoblasts 总被引:8,自引:0,他引:8
Objective: To elucidate the effects of exogenous basic fibroblast growth factor ( bFGF ) on biological characteristics of rat osteoblasts cultured in vitro. Methods: The osteoblasts isolated from a Sprague-Dawley rat and cultured in vitro were treated with different concentrations of bFGF ( 5-50 ng/ml) respectively. At 24 hours after treatment, the proliferating cell nuclear antigen was measured with immunocytochemistry, alkaline phosphatase (ALP) activity was determined and the expression of transforming growth factor beta 1 ( TGF-β1 )was detected to observe the effects of bFGF on growth and differentiation of osteoblasts. Resu/ts: bFGF ( 5-50 ng/ml ) could obviously promote the growth of osteoblasts. The intracellular expression of TGF-β1 mRNA increased significantly, but the intracellular ALP content decreased. Conclusions: bFGF can obviously stimulate the proliferation of osteoblasts and promote the synthesis of TGF-β1, but cannot promote the differentiation of osteoblasts. 相似文献
23.
John T. Leith 《The Prostate》1994,24(3):119-124
Because there is extremely limited information on the intrinsic radiosensitivity of human prostatic cancer cells, we have investigated the in vitro radiation response of exponentially growing LNCaP cells. Due to the very poor colony-forming potential of the LNCaP cells, radiation survival was investigated using the dose-dependent (0-6 Gy) changes seen after X-irradiation in the shapes of regrowth curves. Survival was described using both the single-hit, multitarget (SHMT) equation and the linear-quadratic (LQ) equation. The values and 95% confidence limits of the extrapolation number (n), quasi-threshold dose (Dq), and mean lethal dose (Do) in SHMT terminology were respectively: 0.9 (0.7-1.0), 0.0 Gy, and 1.39 (0.11) Gy. The LQ alpha and beta parameters were respectively 6.80 (1.13) and -0.53 (2.89). The X-ray dose response of the LNCaP line is, therefore, purely exponential. The mean survival at the clinically relevant dose of 2 Gy (S2) was 51.2% for the LNCaP line. Comparison of the S2 value for the LNCaP line with previous investigations with other human prostatic cancer cell lines (DU145 and PC-3) indicates a mean S2 value of 47.6%, which suggests that human prostate cancer cells might lie toward the resistant side of the spectrum for various classes of human neoplasms. © 1994 Wiey-Liss, Inc. 相似文献
24.
介绍了一种新型的防腐杀菌剂--二羟甲基二甲海因的合成方法,采用5,-5二甲海因与甲醛在常压、碱性、冰浴下,反应2小时,产率88.6%。 相似文献
25.
新生儿呼吸机选择的要素 总被引:1,自引:1,他引:0
根据新生儿和成人之间呼吸生理的不同,认为新生儿呼吸机与儿童、成人呼吸机无论从那方面来讲都有较大的区别,并从新生儿呼吸生理的特点出发,提出购买新生儿呼吸机时要注意的几个要素。 相似文献
26.
Otagiri Masaki Yamamichi Ryuji Marayama Toru Imai Teruko Suenaga Ayaka Imamura Yorishige Kimachi Kazuhiko 《Pharmaceutical research》1989,6(2):156-159
The interactions of acidic and basic drugs with 1-acid glycoprotein (1-AGP) were investigated using circular dichroism (CD) measurements. Extrinsic Cotton effects were generated by the binding of drugs to 1-AGP. The CD data suggested the presence of a single binding site on the 1-AGP molecule. The induced ellipticities of the acidic drug–1-AGP system decreased with increasing pH, while the ellipticities for the basic drugs increased with pH. The ellipticities for all drugs were reduced by the addition of fatty acids. Furthermore, the induced ellipticities decreased in the presence of cesium chloride for basic drugs bound to 1-AGP. The extrinsic Cotton effects therefore appear to result from hydrophobic interaction with 1-AGP for the acidic drugs and from hydrophobic and electrostatic interactions for the basic drugs. 相似文献
27.
Developmental Progression in Children's Knowledge of AIDS: Implications for Education and Attitudinal Change 总被引:1,自引:1,他引:1
Osborne Mary L.; Kistner Janet A.; Helgemo Benjamin 《Journal of pediatric psychology》1993,18(2):177-192
The effectiveness of curricula designed to enhance a child'sunderstanding of AIDS may hinge partially upon incorporatinginformation adjusted to the child's developmental status. Accordingly,we examined the developmental progression of children's understandingof illness transmission in general and AIDS in particular, aswell as explored the relation between a child's knowledge ofAIDS and his/her attitudes toward persons with AIDS. Knowledgeof AIDS was manipulated through use of a brief educational intervention.Results support a developmental progression in knowledge aboutAIDS that is consistent with progressions related to illnessesin general. Knowledge enhancement was associated with positivechanges in attitude. 相似文献
28.
Meister U Finck C Stöbel-Richter Y Schmutzer G Brähler E 《Human reproduction (Oxford, England)》2005,20(1):231-238
BACKGROUND: Preimplantation genetic diagnosis (PGD) is a technique which is often related to emotional debates because of its ethical and social implications. Worldwide there are different forms of legislation; Germany constitutes an interesting case because of the historical background concerning eugenics and dealing with handicapped persons at the time of national socialism. PGD is currently not legal but there are still polarized positions and legalization remains an issue. Studies about the attitudes of the general population towards PGD are rare. METHODS: Data were collected in a representative survey carried out in November 2003. Subjects were 2110 persons in Germany aged 18-50 years. RESULTS AND CONCLUSIONS: Respondents had little knowledge about PGD. There were incorrect assumptions about the diagnostic possibilities and a lack of basic genetic knowledge. A tendency towards a general acceptance of PGD for medical indications was found. Non-medical indications such as sex selection were generally not accepted. It could be observed that respondents who already had a notion about PGD overestimated the diagnostic possibilities and would eventually use PGD in the future more than respondents who had never heard about PGD before. 相似文献
29.
Marco Salvetti Giovanni Ristori Mauro D'Amato Carla Buttinelli Marika Falcone Cesare Fieschi Hartmut Wekerle Carlo Pozzilli 《European journal of immunology》1993,23(6):1232-1239
T lymphocytes from patients with multiple sclerosis (MS) recognize multiple myelin basic protein (MBP) epitopes. This situation complicates the design of specific immunotherapies. We investigated to which extent the T cell response to MBP is heterogeneous in single subjects in terms of preferentially recognized regions of the molecule, major histocompatibility complex (MHC) restriction, and stability over time. From each of nine patients with MS, a minimum of six MBP-specific T lymphocyte lines (TLL) were assayed for the proliferative response to a panel of overlapping peptides, encompassing the whole MBP. Predominant Tcell recognitions of distinct MBP regions were present in three patients, all HLA-DR2+, independently of the clinical features of their disease. Tcell reactivity was preferentially directed to residues 16-38 in one patient. In this case the response was also stable over time, during different phases of the disease. Predominant reactivity to residues 86-99 was detected in the two other DR2+ patients. In each of the patients with other HLA-DR haplotypes (DR2?), as well as in three DR2+ non-MS donors, the Tcell response to MBP appeared to be considerably more heterogeneous. The HLA restriction element varied among TLL recognizing the same MBP region, even when raised from the same individual. The genomic HLA typing, performed on the DRB1 and DRB5 genes in the DR2+ subjects, showed no obvious correspondence between preferential responses to regions of MBP and HLA-DR2 subtypes. In this context, a simple, new method for the genomic typing of the HLA-DRB1 gene in individuals with the HLA-DR2 serological specificity is also described. We conclude that predominant and stable T cell responses to a single MBP region can be detected in some patients with MS. In these individuals, the MHC restriction of the T cell recognition of predominant regions appears to be variable. Polymorphisms of the HLA-DR2 gene products alone do not account for the selection of the dominant MBP Tcell epitope. 相似文献
30.
目的:为临床研究提供形态学资料。方法:用免疫组化方法,观察碱性成纤维细胞生长因子(bFGF)在糖尿病小鼠视网膜的分布及表达密度;用透射电镜观察不同病程视网膜细胞的损害情况。结果:糖尿病及正常小鼠视网膜各层细胞均表达bFGF,反应强度和密度不同。发病组自6月龄起,居于大血管周围的阳性节细胞密度增加;不同病程bFGF的表达有不同程度的增加。随糖尿病病程延长,细胞超微结构受到不同程度的损害。结论:糖尿病时增多的bFGF直接或间接作用于血管内皮细胞和平滑肌细胞,刺激二者增殖,促进微血管病变的发生;另一方面,减弱视细胞与双极细胞间的信息传递,对糖尿病性盲的发生起重要作用。同时,各种细胞的超微结构及相应的功能也受到不同程度的损害。 相似文献