Role of intracortical mechanisms in the late part of the silent period to transcranial stimulation of the human motor cortex

Transcranial magnetic stimulation (TMS) and transcranial electrical stimulation (TES) of the human motor cortex produce a silent period (SP) following motor evoked potentials (MEPs). The early part of the SP can be explained by decreased alpha motor neuron excitability, whereas the late part is presumably due to suprasegmental mechanisms. In order to determine the level of the suprasegmental contribution to the generation of SPs, we recorded excitatory and inhibitory responses to TMS, TES, and percutaneous electrical brainstem stimulation (PBS) in the voluntarily activated first dorsal interosseous muscle of the hand. Stimulus intensities were set so that PBS and TES induced MEPs with areas equal to or larger than those of MEPs obtained with TMS. This procedure revealed that SPs were 49% and 83% shorter with TES and PBS, respectively, than with TMS. As TMS is more effective than TES or PBS in activating cortical interneurons, these findings support the idea that a significant component of the SP arises from intracortical mechanisms.     

国产rhGH的免疫原性及其对临床疗效的影响

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     

Effect of UVB 311 nm irradiation on normal human skin

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.     

Cutaneous nerves in patients with diabetic neuropathy--an electron microscopic study

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.     

人血清白蛋白修饰的尿激酶与天然尿激酶的家兔体内过程比较

家兔静注人血清白蛋白修饰的尿激酶(MUK)和天然尿激酶(NUK)40000IU后,MUK 的体内过程符合零级速率过程,NUK 则符合一级速率过程,血纤溶活性 MUK 持续100min,而 NUK 仅20～25min。在“功能性”去除肝肾的家兔,NUK 血浓度半衰期延长3～4倍,而 MUK 血浓度下降与正常家兔相似。MUK 及 NUK 在去除纤溶抑制物的优球蛋白成份中纤溶活性相似,但在血浆中 NUK 仅存24～35%的纤溶活性,MUK 则保留了64～85%的纤溶活性。提示肝肾的摄取、代谢和消除能力降低及对血浆纤溶抑制物抵抗力增强,是 MUK 血纤溶活性长时间维持高水平的主要原因。     

短串联重复序列HumFGA、D3S1359的法医学应用研究

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。     

Multidrug transport in human glioblastoma cells is inhibited by transforming growth factors type beta 1, beta 2, and beta 1.2

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.     

bFGF对人毛囊黑素细胞增殖、活化和黑素合成作用的研究

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     

以病人选择医生为契机 全力推进人事分配制度改革

介绍了邯郸市中心医院在病人选医生中,努力完善制度,提高素质,深化内容,并以此为突破口,建立了灵活、高效的人事分配制度.用较为低廉的医疗费用,为人民群众提供了较好的医疗服务.