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71.
目的 通过测定生长激素缺乏症 (GHD)患儿用国产重组人生长激素 (recom bined hum angrowth horm one,rh GH)治疗时血清生长激素抗体 (GH- Ab)水平及其结合特性 ,探讨 rh GH的免疫原性及其对疗效的影响。方法 对 6 1例 (男 49例 ,女 12例 ) GHD患儿用国产 rh GH治疗 ,每晚睡前皮下注射 rh GH 0 .1IU /kg共6个月 ;用放射免疫法测定治疗期间患儿血清 GH- Ab水平和滴度 ,并计算抗体结合容量、亲和常数 (Ka)。结果 48%患儿 (2 9/6 1)用药后 3个月血清 GH - Ab呈阳性至试验结束时仍未消失 ,其中 2 0例抗体为弱阳性 (结合率 <10 % ) ,9例呈强阳性 (结合率 >15 % ) ;5 2 %患儿 (32 /6 1)治疗期间抗体为阴性 ;血清 GH- Ab的结合容量、Ka及滴度均为低水平 ,分别为 (0 .1~ 4.8) pmol/L、(1.7× 10 7~ 6 .5× 10 8) L /mol和 1∶ 4~ 1∶ 8。GH- Ab阳性患儿治疗后的身高、身高增长速率及身高落后于正常 SD值的变化与同期阴性者比较无统计学差异 (P>0 .0 5 )。结论 本试验所用国产 rh GH对 GHD患儿身高增长具有确切的促进作用 ,其免疫原性所导致产生的 GH - Ab未对患儿体格线性增长产生负性影响 相似文献
72.
U. Ravens Michael O. Flüß Q. Li Herbert M. Himmel Erich Wettwer Michael Klockow Inge Lues 《Naunyn-Schmiedeberg's archives of pharmacology》1997,355(6):733-742
The thiadiazinone derivative [+]-EMD 60263 ((+)-5-(1-(α-ethylimino-3,4-dimethoxybenzyl)-1,2,3,4- tetrahydroquinoline-6-yl)-6-methyl-3,6-dihydro-2H-1,3,4
-thiadiazine-2-on) is a Ca2+-sensitizing agent with only minor phosphodiesterase inhibitory activity. Our aim was to characterize the inotropic and electrophysiological
effects of [+]-EMD 60263 and its enantiomer [-]-EMD 60264 in several cardiac muscle preparations. The Ca2+-sensitizing activity resided in the [+]-enantiomer only. [+]-EMD 60263 (3 μM) shifted the EC50 of Ca2+ for contractile activation of skinned fibers of pig heart from 2.41 μM to 0.73 μM, whereas [-]-EMD 60264 (30 μM) was ineffective.
In Langendorff-perfused guinea pig hearts, [+]-EMD 60263 and [-]-EMD 60264 induced concentration-dependent positive and negative
inotropic effects, respectively; both enantiomers reduced spontaneous heart rate but did not influence perfusion pressure.
The maximum increase in force of human atrial trabeculae was 35 % of pre-drug control with [+]-EMD 60263 in comparison to
113 % with forskolin. In guinea-pig papillary muscles, [+]-EMD 60263 and [-]-EMD 60264 had opposite inotropic responses, however,
both agents similarly prolonged action potential duration. Both enantiomers concentration-dependently blocked the rapidly
activating component IKr of the delayed rectifier in guinea-pig myocytes. The block saturated at potentials positive to +30 mV, closely resembling
the effects of the antiarrhythmic agent E-4031 which had been originally used to define IKr. It is concluded, that the positive inotropic action of [+]-EMD 60263 can be explained by prevalence of the Ca2+-sensitizing effect. The accompanying prolongation in action potential duration is caused by block of the IKr component of the delayed rectifier. While the inotropic effects are stereoselective, most of the electrophysiological actions
are clearly independent of sterical configuration. The combination of Ca2+-sensitizing with class-III antiarrhythmic action may provide an interesting pharmacological profile of potential therapeutic
use.
Received: 7 January 1997 / Accepted: 25 February 1997 相似文献
73.
J. Viac C. Goujon L. Misery V. Staniek M. Faure D. Schmitt A. Claudy 《Photodermatology, photoimmunology & photomedicine》1997,13(3):103-108
Ultraviolet radiation B (UVB) on the skin induces erythema, inflammation and modifications of the immune system. These changes have been reported after excessive short-term or long-term exposure to broad spectrum UVB. In this study, we examined the effects of local repetitive UVB irradiation of 311 nm wavelength on the skin of seven young volunteers. Skin biopsies were taken before and after UVB irradiation, and we immunohistochemically analyzed the expression of CD1a and HLA-DR antigens of Langerhans cells (LC), the possible infiltration of dermis/epidermis by CD11b macrophages, the modifications or the induction of intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1 (VCAM-1) involved in the binding of leukocytes to the endothelial surface and the development of perivascular infiltrates of LFA-1+ mononuclear cells. We also determined the expression of substance P receptors (SPR) using biotinylated substance P (SPB). Exposure of UVB 311 nm induced a drastic reduction of CD1a+ cells and a moderate increase of HLA-DR+ dendritic cells in the epidermis without infiltration by CD11b macrophages. An increase of the binding of SPB to upper layer epidermal cells was noted in five of seven biopsies. In the dermis, vessel-associated ICAM-1 expression increased and an induction of E-selectin occurred on nearly 20 to 40% of endothelial cells, but VCAM-1 expression remained undetectable. The percentage of LFA-1+ cells did not change significantly after irradiation. These observations may be compatible with a selective role of UVB 311 nm on the skin immune response. 相似文献
74.
75.
Yuji Morimoto Osamu Kemmotsu Koichi Kitami Izumi Matsubara Ichiro Tedo 《Journal of anesthesia》1995,9(1):22-26
We evaluated whether we could predict the neurologic outcome in 55 out-of-hospital cardiac arrest patients using auditory
brainstem responses (ABR). ABR patterns were classified into one of 3 types by evaluation of 5 components: type 1, with all
5 components; type 2, lack of at least one response between the 2nd and 5th components; type 3, with only the first component
or no response. The relation between the ABR patterns on the 3rd day following resuscitation and the neurologic outcome on
hospital discharge was evaluated. The specificity that the 5 awake patients had type-1 ABR was 38%. The sensitivity that the
10 brain dead patients had type-3 ABR was 60%. In the type-1 ABR patients, the negative predictive value that the patients
were awake was 100%. In the type-3 ABR patients, the negative predictive value that the patients became brain dead was 90.9%.
These results suggest that ABR on the 3rd post-resuscitation day may not be useful for predicting if patients are awake or
become brain dead, although the loss of components may be a sign of morbidity, and the presence of the 2nd or later components
indicates possible future prevention of brain death. 相似文献
76.
Since the role of cutaneous nerves in the pathogenesis of cutaneous diseases associated with diabetes mellitus is not well defined, cutaneous nerves in ten patients with severe diabetic neuropathy were electron microscopically investigated as a preliminary study. The specimens were taken from normal-appearing skin of their lower extremities. Cutaneous nerves were seen as axon-Schwann cell complexes in which variously degenerated axons and Schwann cells coexisted with normal ones. The degenerative changes were not, however, specific for diabetes mellitus. 相似文献
77.
短串联重复序列HumFGA、D3S1359的法医学应用研究 总被引:1,自引:0,他引:1
对短串联重复序列(short tandem repeats,STR)的两个高多态位点HumFGA(human alpha fibrinogen,人类α-纤维蛋白原基因)、D3S1359的法医学应用进行研究,并通过实际检测案件统计结果进行评估。实验结果表明:两位点灵敏度高,分别为0.2、0.5ngDNA;同一性和可重复性均较理想;种属特异性好,常见动物未发现扩增产物,仅灵长类动物(黑叶猴和猕猴)有扩增条带;复合扩增体系效果良好;在352次减数分裂中,D3S1359未发现突变,HumFGA检测到1次,突变率为0.28%;实际案件统计和应用结果也显示两位点是多态性高,实用性强的两个遗传标记系统。HumFGA和D3S1359在法医学个人识别与亲子鉴定案例中有较大应用价值。 相似文献
78.
H J Schluesener 《Journal of neuroscience research》1991,28(2):310-314
The transforming growth factors type beta 1, beta 2, and beta 1.2 suppress multidrug transport in human pat-1 glioblastoma cells and even in cells that strongly over-express mdr genes and are resistant to inhibition of multidrug transport by chemosensitizers. Thus, inhibition of multidrug transport by cytokines might be a new approach to increase cellular accumulation of chemotherapeutic agents in multidrug resistant glial tumor cells. Interestingly, a member of the more distantly related decapentaplegic subgroup of transforming growth factors, the bone morphogenetic protein BMP 2, did not inhibit multidrug transport. 相似文献
79.
bFGF对人毛囊黑素细胞增殖、活化和黑素合成作用的研究 总被引:3,自引:0,他引:3
目的 研究碱性成纤维细胞生长因子 (bFGF)对人毛囊黑素细胞 (Hairfolloclemelanocyte ,HFM )增殖活化和黑素合成的影响。方法 体外培养正常人HFM ,观察不同浓度bFGF(0 3~ 1 2ng ml)对HFM形态、增殖、酪氨酸酶活性和黑素含量的影响。结果 bFGF处理HFM 7d后 ,HFM树突增多延长 ,酪氨酸酶活性和黑素含量增加显著高于对照组 (P <0 0 1) ,以 0 6ng ml组为著。结论 bFGF能诱导HFM增殖、酪氨酸酶活性和黑素合成增加 相似文献
80.