Heart rate changes after reinforcing brain stimulation in rats

Cardiac responses to hypothalamic and septal stimulation are polyphasic, the first component being accelerative. As interstimulus intervals are decreased, only accelerative components appear, but prestimulus heart rates ("background levels") are decreased upon septal and are either increased or unchanged upon hypothalamic stimulation. The suggestion that parasympathetic responses accompany reinforcing brain stimulation was not supported.     

林区桥梁改造与加固的探讨

林区不同结构类型的桥梁,由于设计、施工、维修养护等诸原因,经过长期的车辆运行,存在着不同程度的破坏和损伤,承载能力及通过能力难以满足现行荷载和日益增长交通量的需要,迫切需要改建或加固补强。本文阐述了林区桥梁改建加固的实用价值和经济效果,并根据其特点介绍了几种可行方案。同时据丰林大桥静、动荷载试验及外观检查结果,提出了加固补强的具体方法。     

钢筋下料长度计算方法探讨

根据钢筋弯曲前后轴线长度不变的特点，提出了用钢筋轴线长度代替钢筋设计长度和下料长度。按照新规范导出钢筋混凝土结构中各种图形、各种规格钢筋的长度计算公式。并将矩形、圆形、绑扎和箍筋的增加长度制成表格。该方法解决了设计尺寸和施工下料长度的统一。     

Intracranial self-stimulation in man

Intracranial self-stimulation techniques, modified for use with neuropsychiatric patients, provide data suggestive of positive and negative reinforcing properties of brief electrical stimulation to various subcortical structures of the human brain.     

Two types of somatostatin receptors differentiated by cyclic somatostatin analogs

Somatostatin receptors in rat brain, pituitary, and pancreas were labeled with two radioiodinated analogs of somatostatins 14 and 28. Two cyclic analogs of somatostatin, SMS201-995 and cyclo(Ala-Cys-Phe-D-Trp-Lys-Thr-Cys), showed biphasic displacement of binding to somatostatin receptors by these radioligands. In contrast, all other somatostatin analogs, including somatostatin-14, competed for the receptor sites with monophasic displacement of radioligand receptor binding. Thus two types of somatostatin receptors were identified. It was found that the pituitary and pancreas have predominantly one type of somatostatin receptor whereas the brain has both, and that different regions of the brain have various proportions of the two types. These findings suggest methods to characterize other types of somatostatin receptors subserving somatostatin's diverse physiological functions, including a potential role in cognitive function and extrapyramidal motor system control.     

基于毒邪理论辨治神经感染性疾病及代谢性脑病——中医脑病理论与临床实证研究(七)

应用毒邪理论指导神经感染性疾病及代谢性脑病的辨治。认为其病机关键是内外之毒,毒损脑络、脑膜、玄府,伤及脑髓;毒邪壅滞,损伤津、血、精、髓等,脑髓失养;由脑府神机受损致全身脏腑功能失调,神机失用。通过列举病毒性脑膜炎、尿毒症性脑病、肺性脑病、一氧化碳中毒迟发性脑病4个医案,阐明针对六淫特征及兼夹内邪特征辨证用药的中药解毒方法,祛邪即解毒,排毒即解毒,扶正即解毒。同时,针对毒邪特征必须注重选择配伍芳香或者苦寒入脑药物解毒。     

Brain evolution triggers increased diversification of electric fishes

Communication can contribute to the evolution of biodiversity by promoting speciation and reinforcing reproductive isolation between existing species. The evolution of species-specific signals depends on the ability of individuals to detect signal variation, which in turn relies on the capability of the brain to process signal information. Here, we show that evolutionary change in a region of the brain devoted to the analysis of communication signals in mormyrid electric fishes improved detection of subtle signal variation and resulted in enhanced rates of signal evolution and species diversification. These results show that neural innovations can drive the diversification of signals and promote speciation.     

Circadian rhythm of brain self-stimulation behavior

Under constant conditions of light, sound, temperature, and humidity, rats exhibited circadian rhythmicity in rate of bar-pressing with hypothalamic and septal reinforcing brain stimulation. Variations in reinforcer magnitude aflected absolute levels of operant response emission but not the frequency of the circadian rhythm. In long sessions, the time of peak responding deviated systematically from a strict 24-hour period. Such data show marked similarity to free-running rhythms of motor activity.     

Isolation of filaments from brain

A method is presented for the isolation of filaments of 90-angstrom diameter from the white matter of bovine brain by first floating the myelinated axons in a centrifugal field and then fractionating the axons on a series of density gradients. This results in a fraction that contains two types of bundles of filaments but few other constituents. The filaments are stable over a wide range of temperatures and at both low and high ionic strength. Their density and their resistance to digestion by ribonuclease and deoxyribonuclease indicate that they are primarily protein. The molecular weight of the subunit is approximately 60,000. The protein does not comigrate with microtubule protein and does not bind cholcicine or nucleotides.     

中华绒螯蟹脑和胸腹神经团的组织学观察

利用组织切片技术研究中华绒螯蟹(Eriocheir sinensis)脑和胸腹神经团的形态学和组织学结构。结果表明中华绒螯蟹的脑位于2个眼柄基部之间,由前脑、中脑、后脑和各部分发出的神经束组成;在脑的切片中可以观察到多种髓质和不同类型的细胞体群。中华绒螯蟹胸腹神经团呈圆盘状,靠近腹甲中央,向外发出多条神经束;在其切片中也可观察到多种类型的细胞体群。详细地描述了中华绒螯蟹的脑和胸腹神经团的组织学结构,为进一步研究中华绒螯蟹的神经分泌细胞奠定了基础,同时也为研究其它甲壳类生物的脑和胸腹神经团的组织结构提供参考。     

Asymmetric cochlear processing mimics hemispheric specialization

Otoacoustic emissions or OAEs (reflections of cochlear energy produced during the processing of sound) were measured in response to two types of stimuli, rapid clicks and sustained tones, in each ear of neonates. OAEs were larger to tones when elicited in the left ear and to clicks when elicited in the right. This finding is similar to those of enhanced processing of tones in right auditory cortical areas and of rapid stimuli on the left, given strong crossed connections from ear to brain. These findings indicate that processing at the level of the ear may facilitate lateralization of auditory function in the brain.     

Mosaic organization of neural stem cells in the adult brain

The in vivo potential of neural stem cells in the postnatal mouse brain is not known, but because they produce many different types of neurons, they must be either very versatile or very diverse. By specifically targeting stem cells and following their progeny in vivo, we showed that postnatal stem cells in different regions produce different types of neurons, even when heterotopically grafted or grown in culture. This suggests that rather than being plastic and homogeneous, neural stem cells are a restricted and diverse population of progenitors.     

金属油罐加强圈的合理确定

金属油罐加强圈的合理确定，对防止油罐罐壁失稳，保证油罐安全生产具有重要作用。分析了目前油罐加强圈的设置现状，针对目前我国油罐罐壁加强圈设计中普遍存在的不足，结合油库油罐使用过程中发生罐壁失稳事故实例，指出设计同罐罐壁加强圈时必须扣除腐蚀裕量值，这样才能保证当腐蚀裕量耗尽时，油罐仍具备足够的罐壁稳定性，同时对加强圈的位置及数量提出了设置意见，考虑到油罐强度要求，扣除值应以罐壁各圈板中腐蚀裕量为最小的     

Proton relaxation rates of water in brain and brain tumors

The distribution of relaxation rates of water in "normal" (autopsy) samples of canine and human brain shows considerable overlap with that for brain tumor samples. The following ranges of values for the spin-spin relaxation rates were observed: for normal brain gray matter, 8.6 to 11.3 sec(-1) (mean, 9.5 sec(-1)); for normal brain white matter, 13.3 to 15.7 sec(-1) (mean, 15.5 sec(-1)); for six types of malignant tumor, 4.8 to 13.4 sec(-1) (mean, 9.3 sec(-1)); for five types of benign tumor, 7.1 to 16.4 sec(-1) (mean, 11.5 sec(-1)). Spin-lattice relaxation rates showed a similar pattern. At least two nonexchanging water components with different relaxation rates were indicated by the analysis of the spin-spin relaxation measurements for the white matter samples.     

Sonic hedgehog control of size and shape in midbrain pattern formation

Little is known about how patterns of cell types are organized to form brain structures of appropriate size and shape. To study this process, we employed in vivo electroporation during midbrain development to create ectopic sources of Sonic Hedgehog, a signaling molecule previously shown to specify different neuronal cell types in a concentration-dependent manner in vitro. We provide direct evidence that a Sonic Hedgehog source can control pattern at a distance in brain development and demonstrate that the size, shape, and orientation of the cell populations produced depend on the geometry of the morphogen source. Thus, a single regulatory molecule can coordinate tissue size and shape with cell-type identity in brain development.     

加热炉炉墙的加固措施

方箱式和弹簧式加热炉是原油管道长距离输送行业使用的传统炉型，该炉型采用的砖砌重型炉墙，在使用过程中由于受热涨冷缩因素的影响，耐火砖墙经常出现内倾，凹凸，开裂等变形损坏现象，为了解决这一问题，对炉墙损坏情况进行了详细的调查后认为：三层墙（耐火砖墙、保温层、红砖墙）之间的耐火拉砖断裂，是造成砖墙损坏的主要原因，为了提高拉砖强度，结合加热炉修理，在墙砌筑时采取了，保留原有拉砖，增设钢筋耐热混凝土拉砖和设     

An opiate binding site in the rat brain is highly selective for 4,5-epoxymorphinans

In vitro binding studies have demonstrated the existence of multiple opiate receptor types. An additional site in the rat brain (termed the lambda site) is distinct from the established types by its selectivity for 4,5-epoxymorphinans (such as naloxone and morphine). While the lambda site displays a high affinity for naloxone in vivo and in vitro in fresh brain membrane homogenates, these sites rapidly convert in vitro to a state of low affinity. The regional distribution of the lambda site in the brain is strikingly different from that of the classic opiate receptor types.     

不同材质漂浮育苗小拱棚对烟苗质量的影响

为探明不同材质烤烟育苗小棚对成苗质量的影响,精简烤烟漂浮育苗小棚制作过程并提高烟苗成苗质量,对竹制池梗拱棚、土夯池梗竹制拱棚和钢筋制池梗小拱棚漂浮育苗的温度、烟苗生育期、长势、出苗率和生物学性状等指标进行对比。结果表明:钢筋制池梗拱棚的干、湿球温度和水温适宜,成苗质量高,出苗率高达93.98%,茎高、茎围、侧根数和干物质积累均表现最好。     

植筋技术在工程中的应用

探讨了植筋技术的特点、应用范围、施工流程、主要技术指标、系统组成、施工措施及质量控制和实际工程应用。     

荷那龙罗非鱼和莫桑比克罗非鱼3种同工酶的分析

采用聚丙烯酰胺凝胶垂直电泳法分析了酯酶(EST)、超氧化物歧化酶(SOD)和乳酸脱氢酶(LDH)3种同工酶在荷那龙罗非鱼O reochrom is hornorum和莫桑比克罗非鱼O.m ossam bicus肝脏、心脏、肌肉、脑和肾脏5种器官组织中的表达情况。结果表明,两种罗非鱼的这3种同工酶均具有明显的组织特异性。EST在两种罗非鱼的肝脏中表达最强,带型最复杂;EST还有种的特异性,如EST-7和EST-8仅分别存在于莫桑比克罗非鱼的心脏和脑器官中,可作为鉴别两种罗非鱼的标记;两种鱼的EST同工酶还具有多态现象。SOD和LDH在两种罗非鱼的酶谱表型、活性等方面非常相似。SOD在肌肉组织中的酶带条数最多,且多数酶带的表达量较高,而LDH在脑、肾脏中表达丰富。同工酶分析结果反映了两种罗非鱼具有较近的亲缘关系,是种间杂交的基础;同时说明两种罗非鱼含有供选择的等位基因,可用于良种选育。