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101.
本文根据光辐射的基本概念,应用数学物理方法,导出了血液辐射治疗仪中带反射罩的紫外线灯的辐照度的计算公式,用XT-A型紫外光功率计,对XL-200型血液辐射治疗仪进行实测,经过计算分析,定出了公式中的待定参数,并应用公式对各实测点进行计算对比,计算值与实测值符合得非常好,发现紫外灯辐射度并简单的指标衰减,为近距离辐照剂量的估算提供了一个有价值的公式,从而将光量子疗法中关于辐照剂量问题的研究定量化。 相似文献
102.
The effect of intrauterine devices (stainless steel ring, copper-T220 and levonorgestrel) on the DNA content in isolated human endometrial cells 总被引:1,自引:0,他引:1
P D Zhu H Z Luo J Cheng R H Xu Y F Liu W M Zheng G Y Song J H Chen Z H Zhou Y M Wu 《Contraception》1989,40(5):591-604
The effect of three different intrauterine devices on the DNA content in human endometrial cells has been studied in 29 women before and after the insertion of an IUD; a stainless steel ring (9 subjects), Copper-T220 (11 subjects) and a medicated IUD releasing levonorgestrel at a rate of 2 micrograms/day (9 subjects). The material was grouped into "bleeders" (having more than 8 days of bleeding and spotting per month) and "non-bleeders" (having less than 8 days of bleeding and spotting per month). The DNA content was assessed on isolated endometrial cells smeared from thin biopsies and the amount of DNA per cell nucleus was measured by means of a Feulgen microspectrophotometric method. No significant difference was found between the "bleeders" and the "non-bleeders" as to the DNA content. Nevertheless, when the total number of subjects were pooled together, a significant increase in the DNA content was found in the post-insertion specimens in the groups of women using the SS and the T-Cu IUDs. Furthermore, a significant decrease in the DNA content was also found when the specimens obtained after the insertion of the LNG IUD were compared with those obtained after 24 months' use of the stainless steel ring and the Copper-T220 device (p less than 0.01 and p less than 0.002, respectively). It is concluded that the insertion of an inert IUD or an T-Cu IUD, induces significant alterations in the DNA content of the human endometrium adjacent to the device, whereas the use of the LNG device does not significantly modify the DNA synthesis when used for 3-10 months. No correlation was found between the DNA content per cell and the number of days of bleeding and spotting. 相似文献
103.
A randomized comparison of pre-and post-experimental design was used to examine the effects of a fall prevention exercise program (FPEP) on muscle strength, ankle flexibility, balance, instrumental activities of daily living (IADLs), and depression for the community-dwelling elderly in Korea. Twenty-two subjects were assigned to an experimental group and twenty-three to a control group. The experimental group participated in a 4-day-per week FPEP of 8 weeks duration, twice a week by direct instruction and twice a week with videotaped instruction by the program instructor at each senior center. The eight-week FPEP turned out to be significantly effective in enhancing muscle strength, ankle flexibility and balance, and in reducing depression, after intervention among community-dwelling elderly in Korea. IADLs, however, was not changed by the intervention. Further research with a larger sample and longer follow up period is needed to expand our understanding about the effects of FPEP. Future study is also recommended to differentiate between the effects of FPEP by direct instruction and by videotaped. 相似文献
104.
105.
Wang H Gordon D Olszewski B Song YL Kovesdi I Keiser JA 《International journal of molecular medicine》2000,6(6):645-653
Therapeutic angiogenesis, either by protein injection or gene therapy, holds considerable promise for the treatment of coronary and peripheral artery diseases. Given the large number of angiogenic genes available, a simple, well defined, standard system to compare the relative angiogenic efficacy of such genes would be valuable. We have employed a replication-deficient adenovirus vector (complete E1a-, partial E1b- and partial E3-) to deliver the beta-galactosidase (beta-gal, AdLacZ) reporter gene or the human VEGF121 gene (AdGV VEGF121.10) to a rat sponge implant model of angiogenesis. beta-gal staining results reveal a transfection efficiency as high as 60% 24 h after 2x1010 particle units AdLacZ injection. Our results also indicate that a single injection of 2x1010 particle units of AdGVVEGF121.10 in the sponge results in >10, 000 pg VEGF protein expression per milligram of sponge tissue 24 h later. VEGF121 protein concentrations decreased 10-fold within 3 days and 100-fold within 7 days after injection. Significant VEGF121 protein levels were still detectable 14 days after initial virus injection. The high level of gene transfection efficiency was accompanied by enhanced angiogenesis in the sponge, a tissue devoid of any vessels before implantation. Compared to control (AdNull: adenovirus vector without the VEGF gene), AdGVVEGF121.10 induced a 2- to 3-fold up-regulation of angiogenesis at 7 and 14 days post vector injection as determined by both increased capillary number and increased tissue ingrowth. The angiogenic effects of AdGVVEGF121. 10 were dose-related in this model system. These findings demonstrate a dose-related angiogenic response to adenovirus-mediated gene therapy in this model. 相似文献
106.
培养细胞整装内质网三维结构的多态性 总被引:3,自引:0,他引:3
用高锰酸钾-锇酸固定法制备了5种培养细胞整装内质网标本,并在扫描电镜下对其三维结构进行了观察。观察结果表明内质网是由膜性小管构成的贯穿整个细胞质的管囊网络样膜性区室,并以多种形态深入到细胞伪足及突起中;细胞质中内质网则表现为簇状网络(见于GCM3T3细胞)、多态性多孔扁囊样网络、筛网状网络、条索状网络、大孔条索网状和细孔扁囊样分区网络、不规则管网状和多孔管囊分区网络(见于CV-1细胞)、细管网络(见于CCL187和CCL229细胞)、球囊网络(见于CCL187和A431细胞)和不规则管网状网络(见于A431细胞)等。内质网的这种多态性提示它是一种高度可变的结构,其可变性可能与细胞特性、分化程度、细胞功能状态及细胞骨架系统的分布变化等因素有关。 相似文献
107.
作者对抗体包被的红为性进行研究,发现抗体包被改变了红细胞的变形性,在我们研究的抗体量范围内,抗体量越多,红细胞的变形性越小,作者从血液流变学的角度对上述结果作了讨论,并提出了通过测定其对红细胞变形性的影响来比较准确地标定抗体效价的可能性。 相似文献
108.
Long Jin Jiangyue Song William F. Chandler Barry G. England James B. Smart Ariel Barkan Ricardo V. Lloyd 《Endocrine pathology》1990,1(1):25-36
The effects of the hypothalamic hormones, thyrotropin-releasing hormone (TRH), and somatostatin (SRIH), and of phorbol 12-myristate
13-acetate (PMA) on PRL and GH secretion and messenger RNA (mRNA) levels were analyzed in 10 GH and/or PRL producing adenomas
after culturing the tumor cells in the presence of these secretagogues for 7 days. The expression of chromogranin A and B
mRNAs was also examined. All four of the clinically diagnosed GH adenomas expressed or secreted both GH and PRL while four
of six clinically diagnosed prolactinomas produced or secreted both PRL and GH. Prolactinomas had less than 10% of tumor cells
expressing chromogranin A mRNA while more than 40% of the adenoma cells expressed chromogranin B mRNA. TRH stimulated PRL
secretion and increased PRL mRNA levels while SRIH decreased GH secretion and mRNA expression in some cases. Unexpectedly,
PMA stimulated PRL mRNA levels four- to sevenfold above control levels in two adenomas and generally stimulated chromogranin
A and B mRNA expression but not GH mRNA, as determined by Northern hybridization and in situ hybridization analyses.
These results indicate that cultured prolactinoma cells express significantly more chromogranin B mRNA than chromogranin A
mRNA, and that PMA increases PRL mRNA expression in some prolactinomas, although the effect of PMA on various adenomas reflects
the heterogeneity of these tumors with respect to protein kinase C stimulation. 相似文献
109.
Mimicking cell membrane and the biomolecular recognition associated with membranes represents a great technical challenge, yet it has opened doors to innovative diagnostic and therapeutic methods. Our work has focused on design and synthesis of a class of smart materials exploiting biological principals for use in biosensors: these materials are functional polymeric assemblies that mimic the cell membrane and conveniently report the presence of pathogens with a color change. Biologically active cell membrane components are incorporated into conjugated polymers with desirable optical properties and the binding of the target molecules onto the material triggers conformational and electronic shifts that are reflected in a chromatic change (a so-called biochromic shift) that is conveniently observed and recorded. Langmuir–Blodgett thin films and vesicle bilayers provide ideal configurations for precise delivery of the biological binding entity to the sensing interface, and for control of molecular orientation for effective biomolecular interaction. Polydiacetylenic membrane-mimicking materials containing cell surface receptor gangliosides and sialic acid residues, respectively were formulated into these architectures and used for colorimetric detection of bacterial toxins and influenza virus. One advantage of these biochromic conjugated polymer (BCP) sensors is that their molecular recognition and signal transduction functionalities are resident in a single functional unit, making them amenable to convenient microfabrication and use. 相似文献
110.
Application of monoclonal antibodies to detect intraocular mycoplasma antigens in Mycoplasma arthritidis-infected Sprague-Dawley rats. 下载免费PDF全文
Sprague-Dawley rats infected with Mycoplasma arthritidis by tail vein inoculation develop extensive disseminated joint inflammation, frequently accompanied by conjunctivitis and anterior uveitis. The intraocular inflammation is apparently directed at mycoplasmas localized within the stroma of the ciliary body, which have been detected with monoclonal antibodies by indirect immunofluorescence. The monoclonal antibodies are directed against an antigenic determinant on the enzyme arginine deiminase isolated from M. arthritidis, but they do not react with the same enzyme derived from Mycoplasma hominis. The antigen bound by the monoclonal antibodies can also be detected by immunofluorescence in M. arthritidis-infected tissue cultures and is not lost after glutaraldehyde fixation or paraffin-embedding procedures. The value in the application of monoclonal antibodies reactive with arginine deiminase lies in the fact that although this enzyme may be found in mycoplasmas and several other species of bacteria it is not a normal constituent of mammalian tissues. 相似文献