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1.
W. B. Quay 《Journal of neural transmission (Vienna, Austria : 1996)》1981,52(1-2):107-115
Summary Quantitative aspects of the microanatomy of the pineal gland and other neuroendocrine and circumventricular structures were studied in a small, reproductively suppressed, female Naked Mole-rat from central Kenya, Africa. The atrophic pineal is the smallest in absolute size (0.002135 mm3) of any so far described in a species of rodent, and in size relative to body weight is second only to that of another tropical species. The subcommissural organ and posterior collicular recess are also relatively small and less well differentiated than those in most other examined rodent species. In contrast, the subfornical organ, OVLT and median eminence are large and well vascularized. It is concluded that the pineal in this species follows the previously described trend among rodents of relatively smaller size in species whose centers of distribution are in lower latitudes. Although the pineal is atrophic, the Naked Mole-rat still exhibits 24-hour and seasonally timed patterns of behavior and seasonal reproduction. However, in this species these events are probably cued by moisture, temperature and social factors rather than by photic information. 相似文献
2.
3.
目的:对环境复杂,基础设施陈旧的大型饲料厂进行鼠害防治研究;方法:在了解大型饲料厂的环境特点及该环境下鼠类的生态特点的基础上,车间及仓库投放0.005%的溴敌隆毒水,外环境投放0.005%的大隆新鲜甜玉米毒饵进行灭鼠;结果:防制措施实施10d后,鼠密度从75.74%降至3.89%;结论:根据鼠的主要生态习性及其生活环境特点,采用投放抗凝血灭鼠药为主的防制办法,完全可以在即不停产不清库的情况下有效地控制大型饲料厂的鼠害。 相似文献
4.
M. Ahmad Agil S. Risco M. Mir M. C. Navarro M. A. Ocete J. Jimnez 《Phytotherapy research : PTR》1995,9(2):135-138
The dried (elaterium) or fresh juice from Ecballium elaterium fruit is used in the treatment of various inflammatory conditions in popular medicine. In this study the elaterium is examined for its analgesic and antipyretic effects in several animal models. The elaterium exhibits both analgesic and antipyretic activities. 相似文献
5.
Steady-state nerve growth factor (NGF) mRNA levels were estimated in male sex organs of the mouse, rat, and guinea pig by RNA blot hybridization analysis. The abundance of NGF mRNAs was in the order vas deferens greater than epididymis greater than or equal to seminal vesicles much greater than testis. NGF mRNA levels in these organs were compared with those estimated for other rat peripheral tissues and were found to correlate with the density of their sympathetic innervation, with the exception of guinea pig prostate. Castration had no significant effect on NGF mRNA levels in the guinea pig prostate, suggesting that NGF synthesis in this tissue is not under direct androgen control. NGF-like and proNGF-like immunoreactivities were localized by immunohistochemical techniques in the secretory cells of the glandular epithelium of the guinea pig prostate and in germ cells in the seminiferous tubules of the mouse testis. 相似文献
6.
灭鼠后家鼠数量恢复的研究 总被引:7,自引:3,他引:4
目的 :探讨灭鼠后家鼠数量恢复情况和规律 ,为制定灭鼠巩固措施提供依据。方法 :采用 0 .0 0 5 %溴敌隆毒米饱和投毒灭鼠 ,后逐月用粉迹法和笼夜法测定鼠密度。结果 :灭鼠较彻底、环境卫生条件好的住宅区 ,低鼠密度可保持 5~ 6个月 ,8个月后鼠密度即恢复到灭鼠前的水平。环境卫生差 ,鼠密度高的农村 ,仅通过毒鼠难以把鼠密度降到较低水平 ;即使通过连续灭鼠把密度大幅度降下来 ,但 1~ 2个月后又恢复至灭鼠前的水平。不同季节灭鼠效果有明显差异。结论 :灭鼠后家鼠数量恢复的速度与灭鼠率、环境卫生条件有关 ,即灭鼠率高、环境卫生条件好的恢复慢 ;否则 ,恢复快。农村灭鼠必须把毒鼠和改造环境结合起来 ,方能有效控制鼠害。 相似文献
7.
Pellegrini-Giampietro DE Cozzi A Peruginelli F Leonardi P Meli E Pellicciari R Moroni F 《The European journal of neuroscience》1999,11(10):3637-3647
Metabotropic glutamate (mGlu) receptors have been implicated in a number of physiological and pathological responses to glutamate, but the exact role of group I mGlu receptors in causing postischaemic injury is not yet clear. In this study, we examined whether the recently-characterized and relatively selective mGlu1 receptor antagonists 1-aminoindan-1,5-dicarboxylic acid (AIDA) and (S)-(+)-2-(3'-carboxybicyclo[1.1.1]pentyl)-glycine (CBPG) could reduce neuronal death in vitro, following oxygen-glucose deprivation (OGD) in murine cortical cell and rat organotypic hippocampal cultures, and in vivo, after global ischaemia in gerbils. When present in the incubation medium during the OGD insult and the subsequent 24 h recovery period, AIDA and CBPG significantly reduced neuronal death in vitro. The extent of protection was similar to that observed with the nonselective mGlu receptor antagonist (+)-alpha-methyl-4-carboxyphenylglycine [(+)MCPG] and with typical ionotropic glutamate (iGlu) receptor antagonists. Neuroprotection was also observed when AIDA or CBPG were added only after the OGD insult was terminated. Neuronal injury was not attenuated by the inactive isomer (-)MCPG, but was significantly enhanced by the nonselective mGlu receptor agonist (1S,3R)-1-aminocyclopentane-1, 3-dicarboxylic acid [(1S,3R)-ACPD] and the group I mGlu receptor agonist 3,5-dihydroxyphenylglycine (3,5-DHPG). The antagonists (+)MCPG, AIDA and CBPG were also neuroprotective in vivo, because i. c.v. administration reduced CA1 pyramidal cell degeneration examined 7 days following transient carotid occlusion in gerbils. Our results point to a role of mGlu1 receptors in the pathological mechanisms responsible for postischaemic neuronal death and propose a new target for neuroprotection. 相似文献
8.
Shigeki Wakiyama Katsuhiko Yanaga Yuji Soejima Takashi Nishizaki Tomoharu Yoshizumi Keizo Sugimachi 《Transplant international》1996,9(4):359-363
We studied the significance of N-acetyl--glucosaminidase (-NAG) and type III procollagen peptide (P-III-P) in the effluent of rodent hepatic grafts. After total hepatectomy, the livers were preserved in chilled, lactated Ringer's solution and then divided into five groups (n=10 each): group 1, 4 h preservation only; group 2, 4 h preservation and rewarming; group 3, 6 h preservation only; group 4, 6 h preservation and rewarming; and group 5, minimal preservation only. The -NAG of groups 2 and 4 was significantly higher than that of groups 1 and 3 (0.98±0.5 U/l vs 0.21±0.12 U/l; P<0.01 and 1.76±0.67 U/l vs 0.38±0.25 U/l, respectively; P<0.01), while that of group 4 was significantly higher than that of group 2 (1.76±0.67 U/l vs 0.98±0.50 U/l; P<0.05). The P-III-P of group 4 was significantly higher than that of group 2 (0.133±0.008 U/ml vs 0.110±0.015 U/ml; P<0.01). We conclude that -NAG is a novel parameter of parenchymal and nonparenchymal cells, while P-III-P reflects the integrity of the hepatic sinusoidal extracellular matrix. 相似文献
9.
The auditory cortex of the Mongolian gerbil comprises several physiologically identified fields, including the primary (AI), anterior (AAF), dorsal (D), ventral (V), dorsoposterior (DP) and ventroposterior (VP) fields, as established previously with electrophysiological [Thomas et al. (1993) Eur. J. Neurosci., 5, 882] and functional metabolic techniques [Scheich et al. (1993) Eur. J. Neurosci., 5, 898]. Here we describe the cyto-, myelo- and chemoarchitecture and the corticocortical connections of the auditory cortex in this species. A central area of temporal cortex corresponding to AI and the rostrally adjacent AAF is distinguished from surrounding cortical areas by its koniocortical cytoarchitecture, by a higher density of myelinated fibres, predominantly in granular and infragranular layers, and by characteristic patterns of immunoreactivity for the calcium-binding protein parvalbumin (most intense staining in layers III/IV and VIa) and for the cytoskeletal neurofilament protein (antibody SMI-32; most intense staining in layers III, V and VI). Concerning the cortical connections, injections of the predominantly anterograde tracer biocytin into the four tonotopically organized fields AI, AAF, DP and VP yielded the following labelling patterns. (i) Labelled axons and terminals were seen within each injected field itself. (ii) Following injections into AI, labelled axons and terminals were also seen in the ipsilateral AAF, DP, VP, D and V, and in a hitherto undescribed possible auditory field, termed the ventromedial field (VM). Similarly, following injections into AAF, DP and VP, labelling was also seen in each of the noninjected fields, except in VM. (iii) Each field projects to its homotopic counterpart in the contralateral hemisphere. In addition, field AI projects to contralateral AAF, DP and VP, field DP to contralateral AI and VP, and field VP to contralateral AI and DP. (iv) Some retrogradely filled pyramidal neurons within the areas of terminal labelling indicate reciprocal connections between most fields, both ipsilateral and contralateral. (v) The labelled fibres within the injected and the target fields, both ipsilateral and contralateral, were arranged in continuous dorsoventral bands parallel to isofrequency contours. The more caudal the injection site in AI the more rostral was the label in AAF. This suggests divergent but frequency-specific connections within and, at least for AI and AAF, also across fields, both ipsilateral and contralateral. (vi) Projections to associative cortices (perirhinal, entorhinal, cingulate) and to other sensory cortices (olfactory, somatosensory, visual) from AAF, DP and VP appeared stronger than those from AI. These data support the differentiation of auditory cortical fields in the gerbil into at least 'core' (AI and AAF) and 'noncore' fields. They further reveal a complex pattern of interconnections within and between auditory cortical fields and other cortical areas, such that each field of auditory cortex has its unique set of connections. 相似文献
10.
广州市家栖鼠对第一代抗凝血灭鼠剂抗药性研究 总被引:3,自引:8,他引:3
目的探讨家栖鼠对抗凝血灭鼠剂的抗药性变化。方法按全国鼠类抗药性监测协作组统一方法,进行无选择性摄毒试验。结果经对广州市所辖9区内捕获的130只褐家鼠、31只黄胸鼠、18只小家鼠进行抗药性监测,其抗性率分别为8.5%、45.2%和27.8%,总平均摄药剂量分别为17.72、278.46和1164.24mg/kg,按家栖鼠抗药性检验标准,黄胸鼠和小家鼠对第一代抗凝血剂杀鼠灵已形成抗药性种群,褐家鼠有抗药性个体产生。结论以黄胸鼠和小家鼠为优势种的场所,要考虑使用第二代抗凝血灭鼠剂;以褐家鼠为主的场所,则可继续使用第一代抗凝血灭鼠剂,但应加强对灭鼠药物的敏感性监测,科学、合理用药。 相似文献