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41.
所有背根节和迷走神经结状节出现大量P物质(SP)阳性胞体和纤维,小细胞占92%,大中型细胞占8%,仅有极少数生长抑素(SS)样神经胞体。大量含SP的纤维和终未见于颈上节和腹腔-前肠系膜神经节,但含SS的纤维和终末主要见于腹腔-前肠系膜神经节,颈上节甚少。交感节中无SP和SS阳性胞体。出现于交感神经节中的SP和SS纤维和终末,可能来自背根节初级感觉神经元的外周侧支或肠神经元。按照这个模式,SP和SS可通过不涉及中枢神经系统的外周短反射环路;去调节交感神经的反应。  相似文献   
42.
Hepatic fibrosis is an effusive wound healing process, characterized by an excessive deposition of extracellular matrix (ECM), as the consequence of chronic liver injury of any etiology. Current therapeutic repertoire for hepatic fibrosis is limited to withdrawal of the noxious agent, which is not always feasible. Hence, in this article, the antifibrotic effects and possible mechanisms of r-sHSA, a recombinant protein with hepatoprotection potential, were investigated. Using NIH/3T3 (mouse embro-fibroblast cell line), skin fibroblasts (human skin fibroblasts, SFBs) and HSC-T6 (rat hepatic stellate cell line), the in vitro effect of r-sHSA was evaluated by measuring the expression levels of alpha-1 Type I collagen (Col1A1) and α-smooth muscle actin (α-SMA). It turned out those fibrosis indicators were typically inhibited by r-sHSA, suggesting its capacity in HSCs inactivation. The antifibrotic activity of r-sHSA was further investigated in vivo on CCl4-induced hepatic fibrosis, in view of significant improvement of the biochemical and histological indicators. More specifically, CCl4-intoxication induced a significant increase in serological biomarkers, e.g., transaminase (AST, ALT), and alkaline phosphatase (ALP), as well as disturbed hepatic antioxidative status; most of the parameters were spontaneously ameliorated to a large extent by withdrawal of CCl4, although the fibrotic lesion was observed histologically. In contrast, r-sHSA treatment markedly eliminated fibrous deposits and restored architecture of the liver in a dose dependent manner, concomitantly with the phenomena of inflammation relief and HSCs deactivation. To sum up, these findings suggest a therapeutic potential for r-sHSA in hepatic fibrosis, though further studies are required.  相似文献   
43.
本研究旨在探讨催产素(OT)是否可以影响雌性山羊腹腔肠系膜前神经节的活动。采用免疫组化SP法观察催产素受体(OTR)在雌性山羊腹腔肠系膜前神经节的分布特点。结果显示,催产素受体在腹腔肠系膜前神经节分布广泛,节内的神经细胞、支持细胞和过路纤维均有OTR免疫阳性产物分布;OTR主要在神经细胞中表达,相对表达量与其他非神经结构相比差异性极显著(P<0.01);在神经细胞中,OTR免疫阳性产物主要存在于胞膜和胞质,核不着色。雌性山羊腹腔肠系膜前神经节神经元对OT具有反应性,提示OT可能通过影响腹腔肠系膜前神经节神经元的活动,从而经其发出的交感节后神经这一途径调节胃肠的生理活动。  相似文献   
44.
AIM: To evaluate the effect of senegenin (Sen) on H2O2-treated retinal ganglion cells (RGCs) and to explore its underlying mechanisms. METHODS: RGCs were retrograde labeled by injection of fluorogold into the superior colliculi of SD rats on the postnatal day 3. On the postnatal days 6 to 8, the retinas were dissociated with papain and cultured. Primary RGCs cultured in vitro were treated with H2O2 and/or various doses of Sen. The viability of RGCs was evaluated by counting the fluorescence-labeled neurons under microscope. The morphological changes of the nuclei in the retinal neurons were observed by Hoechst 33258 staining. Western blotting was applied to determine the expression of cleaved caspase-3, cytochrome C and Bcl-2 in cultured retinal neurons. RESULTS: Compared with the control cells, Sen at doses of 10, 20 or 40 μmol/L had no toxicity to RGCs (P>0.05). However, Sen at doses of 80 and 160 μmol/L had significant toxicity to RGCs (P<0.01). Compared with H2O2-injured group, Sen at doses of 10, 20 and 40 μmol/L effectively protected against H2O2-induced injury in RGCs (P<0.05) with the best efficiency at 40 μmol/L. Hoechst 33258 staining showed that the neuronal apoptosis caused by H2O2 was reduced by Sen. The results of Western blotting showed an up-regulation of Bcl-2, and decreased cytochrome C and cleaved caspase-3 levels by Sen in H2O2-treated retinal neurons. CONCLUSION: Sen is able to protect RGCs from H2O2-induced injury by enhancing Bcl-2 expression and inhibiting cell apoptosis.  相似文献   
45.
北京鸭视网膜节细胞层细胞的分布   总被引:3,自引:0,他引:3  
利用 Nissl染色和计算机图像处理的方法 ,研究了 3 0日龄北京鸭 (P3 0 )视网膜节细胞层 (ganglion cell layer,GCL )细胞的形态大小、数量和密度分布。结果表明 ,北京鸭视网膜节细胞层细胞形态多样 ,有圆形、椭圆形和多角形等。不同区域细胞大小差异显著 ,由视网膜中央区向周边部逐渐增大 (CA为 (53 .3 2± 2 0 .53 )μm2 ;NP 为 89.73± 53 .0 1 μm2 ;TP 为1 4 8.71± 86.2 1 μm2 )。细胞数量分布很不均匀 ,在视网膜中央有一个高密度区即中央高密度区(CA约为为 1 0 660个 / mm2 ) ,且由视网膜中央部向视网膜周边部细胞密度逐渐降低 (TP约为53 40个 / mm2 ;NP约为 583 0个 / mm2 )。可见 ,节细胞层细胞由中央区至周边部由小至大递增而细胞密度梯度呈现递减的变化  相似文献   
46.
AIM:To investigate the pharmacological effects of recombined basic fibroblast growth factor (rbFGF) on retinal ganglion cells (RGCs) of rats.METHODS:Using calibrated cross-action forceps a moderate crush injury was inflicted on the nerve. After crush injury, rbFGF, saline and VB12 were administered by retrobublar injection. Four weeks after injury, the apoptosis of RGCs was measured with flow cytometer.RESULTS:Four weeks after operation, it was shown that the rbFGF, but not saline or VB12 injection could significantly improve the maintainance of RGCs of rats. After 800 U, 1600 U and 2400 U rbFGF injection, the injured RGCs were rescued by 24.5%, 27.3% and 28.5% respectively. Furthermore, it was also found that rbFGF injection could effectively prevent the axons from injury. The flow cytometer showed that the rate of apoptosis was reduced markedly on 7 days at rbFGF group. CONCLUSION:rbFGF can significantly promote the functional repair of injured optic nerve.  相似文献   
47.
番茄E8启动子乙烯应答元件克隆及DNA序列分析   总被引:2,自引:0,他引:2  
E8启动子是常用的番茄果实特异表达启动子之一,是指番茄E8基因5’侧翼近2.2kb的DNA序列。前人的研究表明,E8基因5’侧翼-2181~-1088区段的删除使E8基因表达量大幅度下降(仅为完整E8启动子的1/10),同时该区段还是E8基因对乙烯应答的充分必要区域;这说明了该区段是E8基因表达调控的重要元件。  相似文献   
48.
AIM: To investigate the differentiation of neural stem cells (NSCs) after transplanted into vitreous and the effects on the regeneration of retina ganglion cells (RGCs) after optic nerve microcrushed.METHODS: After optic nerve microcrushed in adult rat,2×104/2 μL NSCs or 2 μL 0.1 mol/L PBS was injected into vitreous.Animals were divided into control group (MC group,MC+PBS group) and experiment group (MC+NSCs).Animals in each group were allowed to survive for 3,4,5 weeks,respectively.The regenerating RGCs were labeled retrogradely with granular blue,and the numbers of regenerating RGCs in each retina were observed under fluorescent microscope.In addition after 5 animals in MC+NSCs group survived for 4 weeks,rat eyeballs were removed and prepared as freezing microtome sections for observing the migration of NSCs and NF,GFAP,CNP immumodetection.RESULTS: Compared the mean numbers of regenerating RGCs between experiment group and control group at 3,4,5 weeks,the difference was significant (P<0.01).NSCs expressed NF,GFAP and CNP at 4 weeks and were not found to incorporate into retina.CONCLUSION: It suggests that NSCs enhance the RGCs regeneration after ON microcrushed and differentiate into neurons,astrocytes and oligodendrocytes.  相似文献   
49.
The purpose of this study was to define ganglion cell density, size and topography in the retina of the mallard duck. After killing adult mallard ducks (Anas platyrhynchos var. domesticus), their eyes were removed using pentobarbital (30 mg/kg). The retinas were isolated, whole mount specimens were prepared by staining with 0.1% cresyl violet and then fixing the tissues for study. The retinal ganglion cells were counted, mapped and measured. The mean total number of ganglion cells was estimated at approximately 1.7 × 106 and the retinal area centralis had the highest ganglion cell density with 15 820 cells/mm2. The number of ganglion cell bodies was highest in the temporal area, followed by the nasal, dorsal and ventral areas. Ganglion cell size ranged from 56 to 406 μm2. A population of small ganglion cells persisted into the central area just above the optic disc and the largest soma area was in the ventral zone of the retina. This localization of ganglion cells suggests that the quality of vision is not equal in all the areas of the duck retina and the central part may have the highest vision quality as a function of the retinal ganglion cells.  相似文献   
50.
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