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201.
大鼠大脑皮质投向小脑前核纤维终末的超微结构和突触联系 总被引:3,自引:0,他引:3
白德成 《兰州大学学报(自然科学版)》1997,33(4):101-106
用溃变电镜法观察了12只大鼠小脑前核中皮质下行纤维终末的溃变变化,纤维形式及突触联系,结果表明,皮质纤维有三种溃变变化,以电子致密型变化为主。电子致密型溃变终末有三种纤维形式,即含圆形清亮小泡,多形小泡和混合型小泡终末。 相似文献
202.
《科学通报(英文版)》1993,38(24):2083-2083
203.
S. Curello C. Ceconi C. Bigoli R. Ferrari A. Albertini C. Guarnieri 《Cellular and molecular life sciences : CMLS》1985,41(1):42-43
Summary In the isolated and perfused rabbit heart ischemia induced a rapid decline of contractility, associated with a reduction of the content of tissue GSH with no significant changes in GSSG. Reperfusion induced a small recovery of contractility, a substantial release of total glutathione and a further decrease in the content of tissue GSH with a significant increase of tissue GSSG. Glutathione reductase and glutathione peroxidase activities were not affected by ischemia and reperfusion. This study suggests a possible role for glutathione in the determination of functional damage induced by myocardial ischemia and reperfusion.This study was supported by a grant from Ministero Pubblica Istruzione and CNR Rome (no 8202331.56). 相似文献
204.
WUDanli ZHANGYourong LAOMiaofen YUANLizhen WANGLan HAXiaoqin WUZuze 《科学通报(英文版)》2004,49(14):1464-1469
After the study in vitro and in rats, we assessed further the effects and safety of local angiogen therapy using intramyocardial delivery of an adenovirus carrying hepatocyte growth factor gene (Ad-HGF) in a canine ischemia model. The angiogenic activity of Ad-HGF was evaluated from three aspects. First, the augmentation of collateral vessel development was assessed by angiography 30 d after surgery. The results showed that the density of collateral vessels in treated group was higher than that of control group. Secondly, infarct size was evaluated by TTC staining and image analysis. The results showed that the infarct size of treated group was smaller than that of control group. Thirdly, the myocardial regional blood flow was determined by the method of colored microspheres. The results showed that the blood flow recovered to the level before ligation in treated group, but that of the control group was lower than normal level. In addition, during the study of chronic toxicity, we tested the anti-adenovirus antibodies by neutralization method. The antibodies yielded after the fourth injection decreased slowly from peak level and disappeared 12 weeks after drug withdrawal. Overall, Ad-HGF can promote angiogenesis in ischemic myocardium and reduce infarct size. So this method may be considered as a therapeutic angiogenesis induction strategy for ischemic disease including myocardial infarction and peripheral artery disease. At the same time, Ad-HGF could induce the yield of anti-adenovirus antibodies to neutralize adenovirus, which may be the mechanism of adenovirus clearance. 相似文献
205.
为讨论缝隙连接阻断剂18β—GA在脑血管收缩反应中的可能作用。采用压力肌动图技术,在急性分离的Wistar大鼠的大脑中动脉(直径〈300μm),观察18β—GA干预前后不同浓度的收缩剂KCl对血管直径的影响。结果显示,KCl可以浓度依赖性的引起脑中动脉收缩,且30~80mmol/L引起的收缩与血管静息状态下的直径相比具有统计学差异(P〈0.05,n=7)。18βGA也可浓度依赖性的引起脑中动脉收缩,且10~100〉mol/L引起的收缩与未加药前相比具有统计学差异(P%0.05,n=8)。预灌流18β—GA(100/amol/L)后,50~80mmol/L KCl引起血管收缩幅度减小,拟合曲线下移,且差异具有统计学意义(P〈0.05,n=7)。由此可知:18B—GA可抑制KCl对脑血管的收缩作用,提示细胞问缝隙连接参与脑血管收缩活动。 相似文献
206.
207.
Summary The subcommissural organ (SCO) of the congenital hydrocephalus spontaneously occurring in CWS/Idr rats was severely reduced in size and displaced at some distance from the anterior end of the cerebral aqueduct. The cerebral aqueduct of the hydrocephalic rats was open throughout its total length during postnatal days 1–20, though it was somewhat narrower at its middle region than in the normal brain. 相似文献
208.
209.
Rostagno A Tomidokoro Y Lashley T Ng D Plant G Holton J Frangione B Revesz T Ghiso J 《Cellular and molecular life sciences : CMLS》2005,62(16):1814-1825
The importance of cerebral amyloid deposition in the mechanism of neurodegeneration is still debatable. Classic arguments are usually centered on amyloid β(Aβ) and its role in the neuronal loss characteristic of Alzheimer’s disease, the most common form of human cerebral amyloidosis. Two non-Aβ cerebral amyloidoses, familial British and Danish dementias (FBD and FDD), share many aspects of Alzheimer’s disease, including the presence of neurofibrillary tangles, parenchymal preamyloid and amyloid deposits, cerebral amyloid angiopathy and a variety of amyloid-associated proteins and inflammatory components. Both early-onset conditions are linked to specific mutations at or near the stop codon of the chromosome 13 gene BRI2 that cause generation of longer-than-normal protein products. Furin-like processing of these longer precursors releases two de novo-created peptides, ABri and ADan, which deposit as amyloid fibrils in FBD and FDD, respectively. Due to the similar pathology generated by completely unrelated amyloid subunits, FBD and FDD, collectively referred to as chromosome 13 dementias, constitute alternative models for studying the role of amyloid deposition in the mechanism of neuronal cell death.Received 4 March 2005; received after revision 24 April 2005; accepted 26 April 2005 相似文献
210.
FANG Ke LI Yingxia LIU Hua LIAO Weijing & LEI Hao .State Key Laboratory of Magnetic Resonance Atomic Mo- lecular Physics Wuhan Institute of Physics Mathematics Chinese Academy of Sciences Wuhan China .Zhongnan Hospital of Wuhan University Wuhan China 《科学通报(英文版)》2004,49(17):1834-1840
Manganese enhanced magnetic resonance imaging(MEMRI) is a novel neuroimaging technique first intro-duced by Lin et al. in 1997[1]. In this technique, bivalentmanganese ion (Mn2+) is used as a tracer for Ca2+, an im-portant substrate for neurotransmission. By monitoring thetransportation of Ca2+ between the cells and synapses,MEMRI can be used in vivo to trace neuronal tracts and tostudy brain functions dynamically. That Mn2+ can be usedas the tracer for Ca2+ is because it has two special… 相似文献