The relationship between long latency responses and height

Summary Long latency responses to electrical stimulation of nerve trunks in upper and lower extremities were studied in 83 healthy subjects. The latency differences between the late responses, M2, and the segmental reflexes, M1, on the hand correlated with the height, confirming a transcortical reflex loop. Corresponding to the possible polysynaptic spinal origin of the late reflex response on the lower leg, there was no correlation with height. Therefore, it is not possible to calculate the intraspinal conduction time from long latency reflex examinations.     

Different neuroleptics show common dose and time dependent effects in quantitative field potential analysis in freely moving rats

Under the assumption that field potentials recorded from particular brain areas reflect the net balance of neurotransmitter activities, the dose- and time-dependent responses induced by intraperitoneal application of different neuroleptic drugs are quantified by spectral analysis of the electroencephalogram recorded from frontal cortex, hippocampus, striatum and reticular formation. The actions of haloperidol, chlorpromazine, clozapine, prothipendyl and thioridazine in general were characterized by increases of the spectral power in the alpha₁ and beta range, at higher dosages also in the theta range. This observed pattern of changes is in line with the neuroleptic induced spectral changes reported in the literature for other animals and man. In the light of the already known effects of other psychoactive drugs on the frequency content of field potentials in the rat, it should now be possible to classify different drugs in terms of their clinical indication. With respect to the type of neurotransmitter control underlying the changes produced by various neuroleptics, it is quite obvious from the comparisons with the respective drug effects that dopamine-D₁-receptor controlled transmission is not responsible for this action. On the basis of earlier findings a possible interaction between dopamin-D₂ receptor or glutamatergic transmitter control is discussed.     

圣地红景天长期毒性试验

研究圣地红景天对大鼠的长期毒性；８０只大鼠平均分成四组，其中三组灌胃给予不同剂量的圣地红景天（５０ｇ／ｋｇ，１．０ｇ／ｋｇ，０．２ｇ／ｋｇ），另一组为对照组，给予同体积蒸馏水。灌胃期间，每周测体重一次。然后在规定的时间断头取血５ｍｌ进行外周血象和肝肾功能检测；各给药组与对照组比较，各项指标均无显著性差异；圣地红景天长期使用毒性小，无延迟毒性，临床使用安全     

高龄患者肾移植的临床研究

我院自１９７８年４月至１９９３年１０月施行同种异体尸肾移植术５４７例次，其中５０岁以上患者８１例，占１４．８％。术后常见的并发症为肺部感染、脑血管意外、心肌梗塞及道出血。死亡率高于低危人群肾移植患者。１年人／明存活率为８５．７％／８１．５％。本文就高龄患者肾移植手术的适应症、术后新型免疫抑制剂的应用及长期存活的经验进行讨论。     

123I-metaiodobenzylguanidine scintigraphy in the detection of irregular regional sympathetic innervation in long QT syndrome

Twelve patients with the long QT syndrome were studied to determinethe usefulness of ¹²³I-metaiodobenzylguanidine (MIBG) single-photonemission tomography (SPECT) at 2 h and 6 h after injection;the results were compared to 10 healthy volunteers (controls).Uptake of MIBG in the left ventricle at 2 h after injectionwas significantly reduced in patients with the long QT syndrome(1.43±0.13) vs 1.66±0.15 in controls, heart-to-mediastinumratio, P <0.002) and washout after 6 h was faster on a planarview image. Decreased MIBG uptake could be observed preferentiallyin the anterior and lateral walls near the apex. The half-timevalues of MIBG washout from the left ventricle were significantlyreduced in the long QT syndrome (6.4±1.5 h) comparedto controls (16.7±15.3 h, P <0.002). In three cases,the same pattern of disturbed activity distribution was maintainedeven after surgical left cardiac sympathetic denervation. Thepresent results strongly support the hypothesis that an inhomogenousregional distribution of sympathetic nerve terminals accompaniedby an overall reduction in their absolute number may play animportant role in the pathogenesis of the long QT syndrome.Additional functional disturbances, possibly related to theuptake of catecholamines in the left ventricle may coexist withregional inhomogeneity of nerve terminals. The differences observedfrom one case to the other may be related to the variation inseverity of the disease. MIBG SPECT imaging seems an interestingnew tool for the quantitative assessment of presynaptic sympatheticnerve terminal disturbances in the left ventricle of patientswith the long QT syndrome.     

上海“6.25”60Co源辐射事故中5例重、中度骨髓型急性放射病18个月的随访观察报告

目的１９９０年发生在上海的“６．２５”６０Ｃｏ源辐射事故所致的骨髓型急性放射病重度２例，中度３例急性期救治获临床治愈，在事故后１８个月进行了随访。方法按照“后效应临床随访研究组”的计划定期系统复查，观察迟发性的远后生物学效应。并进行相关治疗。结果１８个月早期系统随访观察显示：①血象、骨髓象、造血祖细胞培养各种数值仍偏低；②红细胞酶和膜的蛋白组分仍有异常；③免疫功能，尤其是细胞免疫功能仍不全；④染色体检查分析显示以稳定性畸变为主，早期表现的双着丝点加环改变已明显消退，且与病人辐射剂量相关；⑤双眼晶体后囊轻度混浊，眼底视网膜血管扩张；⑥甲皱与球结膜微循环仍显示舒－缩功能紊乱，与血清ＡＴ－１和ＡＴ－２水平未恢复正常相一致；⑦精液检查显示精子数量减少，活率和活力减退与病人辐照剂量相关；⑧部分内分泌功能仍未恢复正常。结论根据上述照后１８个月早期观察结果，说明，虽然这些病人从急性期获得了临床治愈，但他们的组织器官仍然存在潜在迟发性后继损害。因此必须从分子生物学、细胞学和整体观察水平，由多学科联合进行长期观察研究。作者提出了长期评价辐射的生物学效应的随访研究初步方案     

用牛免疫缺陷病毒筛选抗艾滋病药物的实验模型

本文应用牛免疫缺陷病毒（BIV）合胞体形成和BIV长末端重复序列（LTR）引导的萤火虫荧光素酶（Luc)基因表达分析，建立了抗艾滋病（AIDS）药物的筛选和评价模型，BIV合胞体形成及BIV－LTR引导的Luc基因活力与BIV感染的细胞呈线性关系，临床有效药物3‘叠氮胸嘧啶脱氧核苷（AZT）可显著抑制BIV合胞体的形成及BIV－LTR引导的Luc基因表达水平，并有剂量依赖关系，上述两种分析得到AZT的IC50分别为0．24和052umol/L。     

Effects of long term GnRH analogue treatment on hormone levels and spermatogenesis in patients with carcinoma of the prostate

Summary The effects of long term GnRH treatment with the biodegradable depot formulation of ICI 118.630 on hormone levels and spermatogenesis were investigated in 18 males with advanced prostate cancer. Plasma levels of FSH, LH, testosterone, DHEA-S and SHBG were monitored at regular intervals. The drug suppressed FSH, LH and testosterone significantly and did not affect DHEA-S and SHBG plasma levels. Tissue specimens for histologic assessment and quantitative analysis of germinal cell types were obtained at secondary orchidectomy in 16 patients immediately following GnRH analogue treatment. Germinal cell maturation was arrested at the spermatogonial stage. In two patients discontinuing treatment histologic assessment of secundary orchidectomy specimens 9 and 10 months after the last GnRH analogue depot injection resulted in germinal cell maturation to late spermatides in part of the tubule cross sections. These results indicate that long term administration of the GnRH analoge fails to produce complete testicular sclerosis and spermatogenic arrest might be reversible.     

Calcium-induced long-term potentiation in the hippocampal slice: Characterization of the time course and conditions

A transient increase in extracellular calcium concentration causes a long-lasting enhancement of radiatum fibers evoked excitatory postsynaptic potential and population spike responses of CA1 pyramidal neurons which resembles long-term potentiation (LTP). The duration of this potentiation is much longer than described previously and is probably limited by the survival of the preparation itself (greater than 8 hr). Therefore, Ca-induced LTP can be used for the investigation of a postulated late phase of LTP. Ca effects were activity-independent, since the subsequently evoked responses were facilitated even when the presynaptic fibers were not concurrently stimulated during or immediately after superfusion with the high Ca medium. In contrast, if too frequent testing of the synaptic input was done during the high Ca pulse, a short lasting depression instead of potentiation was observed. A lower extracellular magnesium concentration in the standard medium (1.3 instead of 2.0 mM MgSO4) prevents the potentiation of the EPSP at least for the first few hours. Presumably, both tetanus- and Ca-induced LTP share some common mechanisms, since an additional tetanization after Ca induction was not followed by an additional LTP. Compared to the potentiation following tetanization, the Ca-induced LTP was, however, not accompanied by a potentiation of the EPSP/spike ratio within the range of the population spike threshold intensity.