Unpredictable and uncontrollable stress impairs neuronal plasticity in the rat hippocampus

Almost by definition, learning and the effect of stress on learning represent modifications of existing neuronal circuitry. Under some circumstances, this modification can be measured electrophysiologically. One such measure of plasticity is long-term potentiation (LTP), a long-lasting increase in synaptic efficacy following brief exposure to tetanic stimulation. In 1987, Foy et al. reported that hippocampal LTP was impaired by exposure to inescapable shock. We have recent evidence that the impairment in LTP can be prevented by allowing the animal to learn to escape the shock (Shors et al., 1989), indicating that the stress effect is to some extent mediated by "psychological" variables. Regardless of LTP's putative role in learning and memory processes, such a stress-induced decrease in neuronal plasticity is likely to have profound effects on the behaving organism.     

The concept of distinct but voluminous groups of bipolar and unipolar diseases

Summary One hundred and six affective (76 unipolar and 30 bipolar) and 101 schizoaffective patients (45 unipolar and 56 bipolar) were investigated after a long-term course of illness, evaluating sociodemographic and general data, the long-term course of illness, disability and psychosocial alterations according to WHO/DAS, WHO/PIRS and GAS, as well as several social consequences of the illness (living situation at the end of the observation time, downward occupational drift, downward social drift, premature retirement, achievement of the expected social development). Comparing the 30 bipolar affective and 56 bipolar schizoaffective disorders, no differences were found regarding (a) sociodemographic and general data (i.e. sex distribution, age at onset, education and occupation at onset, stable heterosexual relationship, premorbid personality and social interactions, mental illness in the family, broken home, life events, season of birth and social classes) and (b) relevant patterns of the long-term course. Regarding long-term out-come the only difference found concerned the more favourable outcome of the bipolar affective disorders according to WHO/DAS, while using GAS the difference was not statistically significant. No difference was found either between the two bipolar groups in the social consequences of the illness. The combining of both bipolar groups as bipolar diseases is discussed, as well as the use of the terms bipolar disease, affective subtype and bipolar disease, schizoaffective subtype.     

晚期肿瘤的治疗及其价值

晚期肿瘤是否有治疗意义的讨论越来越受到社会的关注。作者从医学及伦理学两方面论述晚期肿瘤的治疗意义,认为治疗有助于疾病的控制,有利于提高患者的生存质量。指出晚期肿瘤的治疗并非无效治疗,患者能从治疗中得益。     

幽门螺杆菌感染与肝硬化关系的研究

目的：研究肝硬化患者的幽门螺杆菌（HP）感染状况及其对肝性脑病和上消化道出血的影响。方法：用尿素酶快速染色和瑞一姬染色确定HP的感染,分析肝硬化与十二指肠疾病患者HP感染率的差异;HP感染对肝硬化患者血氨浓度的影响;随访HP阳性与阴性肝硬化患者肝性脑病的发生率;观察肝硬化并上消化道出血与非出血患者间HP感染的差异。结果：肝硬化与胃十二指肠疾病患者HP感染无明显差异;HP感染能使肝硬化患者血氨浓度增加,从而使肝性脑病发生率增高;肝硬化并出血与非出血组HP感染无明显差异。结论：肝硬化患者的HP感染无特异性;HP感染能促使肝性脑病的发生;HP感染在肝硬化并上消化道出血中未起主要作用。     

二尖瓣-主动脉瓣置换术近期和远期效果的评价

目的 :评价单瓣与双瓣置换术的近期与远期效果。方法 :70例风湿性心脏病人采用国产上海碟瓣行机械瓣置换术 ,其中单纯行二尖瓣 (MV)置换术者 47例 ,二尖瓣加主动脉瓣 (AV)双瓣置换术者 2 3例。生存者 10 0 %随访 1～ 7年 (平均 4.76± 1.7年 )。结果 :院内死亡 4例 ,死亡率为 5 .71%。随访中死亡 2例 ,远期死亡率为 0 .63 %人·年。 7年生存率为 95 .69% ,10年生存率为 93 .89%。 94.0 0 %术后心功能均改善Ⅰ～Ⅱ级。结论 :房颤 (Af)并Ⅱ度房室传导阻滞的病人应暂缓手术 ;国产上海碟瓣有良好的血流动力学特性 ;只要处理恰当 ,双瓣手术的危险性不比单瓣手术的危险性高。     

标准通道经皮肾镜取石术治疗孤立肾肾结石的长期安全性和有效性

目的: 探讨超声引导下标准通道经皮肾镜取石术(percutaneous nephrolithotomy,PCNL)治疗孤立肾肾结石患者的长期有效性和安全性。方法: 回顾性分析2008年9月至2014年6月于北京大学人民医院行PCNL治疗的22例孤立肾肾结石患者临床资料以及5年以上随访资料,记录围手术期相关指标、术后无石率(stone free rate,SFR)及并发症发生率,采用超声检查评估远期结石复发率,通过血肌酐及估计肾小球滤过率(estimated glomerular filtration rate, eGFR)评估肾功能情况。结果: 本组22例患者中,平均年龄为(50.3±11.8)岁,10例解剖性孤立肾,12例功能性孤立肾,中位结石直径为1.65(1.1~3.9) cm,全部为多发结石,包括7例鹿角形结石。术前的中位血肌酐为104.5(60.0~460.0) μmol/L,平均eGFR为(60.3±29.4) mL/min。平均手术时间为(88.2±42.0) min,各有11例单通道和双通道PCNL。术后第一天的中位血肌酐为102.0(63.0~364.0) μmol/L,平均eGFR为(58.0±25.1) mL/min,与术前相比差异均无统计学意义。术后平均住院时间为(8.7±5.2) d。本组有5例(22.7%)患者出现短期并发症,其中4例患者同时出现术后感染和大量出血,保守治疗后好转,1例患者出现胸膜损伤,行胸腔闭式引流后好转; 2例(9.1%)患者出现长期并发症,术后3个月发生输尿管狭窄,行球囊扩张术后好转;其余15例(68.2%)患者均未见并发症。中位随访时间为6.2(4.7~11.1)年,最近一次随访的中位血肌酐为104.0 (72.4~377.0) μmol/L,平均eGFR为(60.1±23.7) mL/min,与术前相比差异均无统计学意义,6例(27.3%)患者出现肾功能减退。术后初始和最终SFR分别为72.7%和100%; 6.2年的随访时间内9例(40.9%)患者结石复发,复发后共进行13次取石手术,最近一次随访的SFR为63.6%。结论: 本研究目前是国内外已有报道中关于孤立肾肾结石患者PCNL术后随访时间最长的研究,超声引导下标准通道PCNL治疗孤立肾肾结石是安全有效的,可以达到理想的SFR。长期随访结果表明仍有较高的结石复发率,但术后患者远期肾功能稳定,部分患者出现轻度肾功能减退。     

头高位倾斜时心血管反应的仿真

仿真头高位倾斜时心血管系统的反应,进一步研究有关立位应激的生理机制。方法以仿真下体负压时心血管反应的模型为基础,在血液重新分配子模中引入了重力致血液重新转移的环节,在压力反射控制子模型中考虑了心水平与颈动脉压力感受器间的流体静压差。     

综合医院确诊的39例肺结核患者转诊结果随访调查

目的;了解并评价综合医院内科确诊的活动性肺结核病例转诊结果。方法：对我院呼吸内科１９９５年８月－１９９８年８月确认的３９例活动性肺结核患者（不包括结核性胸膜炎）转往结构防治专业机构的结果进行信访和电话随访。结果：仍的３９例活动性肺结核患者中有３５例在确诊后１周内结核病接受０．５ａ－１ａ的全地化疗,３３例获得良好效果,２例死亡,死因分别为肺间质纤维化合并感染肺心病及呼吸衰竭。３例慢性纤维空洞型肺结核     

国产房水引流物置入术治疗难治性青光眼远期疗效观察

１９９３年７月～１９９８年１月为１０３例（１０６只眼）难治性青光眼患者施行国产房水引流物（ＨＡＤ）置入术。术后平均随访３２８月。术后１年时平均眼压２２±１．４ｋＰａ。术后１～５年的手术成功率分别为８３８％,８０４％,７７１％,７１０％及６４３％。术中联合应用丝裂霉素Ｃ的病例,其术后１年时的成功率为８９５％。术后常见的并发症有持续性浅前房,局限性脉络膜脱离及眼压升高等。认为ＨＡＤ可用于治疗难治性青光眼。     

A 'long-term-potentiation-like' facilitation of hippocampal synaptic transmission induced by the nootropic nefiracetam

Nefiracetam, a nootropic agent, enhanced the slope of field excitatory postsynaptic potentials in the CA1 region of rat hippocampal slices to about 170% of basal levels, being evident still at 4-h washing-out of the drug. A similar sustained enhancement (>/=16 h after i.m. injection with nefiracetam) was observed in the population spikes recorded from the granular cell layer of the intact mouse hippocampus. Saturation of the enhancement in the synaptic strength occluded potentiation obtained with long-term potentiation (LTP) induced by high-frequency (tetanic) stimulation, and vice versa. Interestingly, the facilitatory action of nefiracetam was blocked by either the nicotinic acetylcholine (ACh) receptor antagonists, alpha-bungarotoxin and mecamylamine, or the selective protein kinase C (PKC) inhibitor, GF109203X, but in contrast, it was not affected by D-2-amino-5-phosphonovaleric acid (APV), a selective N-methyl-D-aspartate (NMDA) receptor antagonist. The results of the present study suggest that nefiracetam, whereas the action is independent of NMDA receptors, induces an 'LTP-like' facilitation of hippocampal synaptic transmission as a consequence of modulation of nicotinic ACh receptors and PKC. This may represent a likely mechanism underlying the cognition-enhancing actions of nefiracetam.