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21.
目的:探讨双环己酮草酰二腙(cuprizone,CPZ)介导急性脱髓鞘小鼠海马中nestin的表达。方法:用掺入0.2%CPZ的普通饲料饲养C57BL/6小鼠6周,制备脱髓鞘模型,然后使用免疫荧光染色、q RT-PCR、Western Blot方法,检测小鼠脑内髓鞘脱失后海马中nestin的表达变化。结果:(1)体重称量结果显示:CPZ组体重明显低于对照组(P0.01);(2)免疫荧光结果显示:CPZ组海马CA区和DG区颗粒细胞层中nestin阳性细胞明显低于对照组分别为:P0.05,P0.01;(3)Western Blot和q RT-PCR实验结果显示:CPZ组海马中nestin蛋白和m RNA含量均明显低于对照组(P0.05)。结论:CPZ介导小鼠急性脱髓鞘后海马内nestin表达降低,提示髓鞘脱失可能会抑制nestin表达。  相似文献   
22.
目的:采用免疫组化方法标记大鼠肝卵圆细胞中巢蛋白Nesin的表达,探讨肝卵圆细胞新的表面标记蛋白。方法:用化学致癌剂3’-甲基4-二甲基氨偶氮苯(3’-Methy-4-dimethylaminoazobenzen,3’-me-DAB)喂养SD大鼠4周,取大鼠肝脏,用免疫组化法标记神经前体细胞的特异性表面标记物巢蛋白Nestin在大鼠肝卵圆细胞中的表达。结果:汇管区靠近界板处卵圆细胞表达Nestin阳性,Nestin阳性细胞成簇状分布或呈双层排列成管状,主要集中在赫令氏管周围并见Nestin阳性细胞向肝小叶内迁移,散在分布于肝细胞索。结论:大鼠肝内存在Nestin表达阳性的卵圆细胞,Nestin可能是肝卵圆细胞新的标记蛋白。  相似文献   
23.
大鼠骨髓细胞体外诱导分化神经细胞的演变规律   总被引:3,自引:0,他引:3  
[目的] 摸索从全骨髓诱导培养分化神经细胞的方法,并从神经巢蛋白(nestin)和神经核蛋白(NeuN)两种标记物上观察其分化的演变规律.[方法] 抽取 SD大鼠骨髓做全骨髓细胞培养,采用免疫细胞化学和荧光激活细胞计数仪 (FACS)追踪由骨髓到神经元样细胞不同阶段 nestin和 NeuN的表达趋势,给予定性、定量分析.[结果] 免疫细胞化学检测,细胞培养 5 d时对上述抗体呈弱阳性,逐渐增强,培养第 15天细胞呈典型 nestin强阳性反应,而 NeuN强阳性反应在 25~ 30 d达到高峰,发育成为神经元样细胞. FACS同步追踪显示了 nestin和 NeuN在培养第 5天时即有表达,前者 3.4%,后者 2.5%.随着骨髓细胞的分化,在 15 d时 nestin阳性细胞为 22.7%,达到高峰,随后下降. NeuN于 30 d达到高峰为 41 2%,而此时 nestin阳性细胞为 5.9%.[结论] 从神经干细胞和神经细胞特征性标记物演变探知骨髓细胞的分化发育规律;骨髓细胞可分化为神经细胞;骨髓源性神经前体细胞早期亦有 nestin和 NeuN的表达.  相似文献   
24.
25.
Tritiated thymidine studies suggest that Müller cells are the last cells born in the retina, although several authors describe Müller cells throughout the retina from very early ages. In this study immunohistochemistry was used to identify progenitor and Müller cells in human foetal retina. Antibodies to nestin (an intermediate filament protein expressed by neural progenitor cells), vimentin, cellular retinaldehyde binding protein (CRALBP) and glutamate and aspartate transporter (GLAST), which are each expressed by Müller cells, were used in combination with anti-Ki67 to identify proliferating cells. By definition, Ki67-positive proliferating cells were present in undifferentiated retina, but not in differentiated retina. Nestin-immunoreactive (IR) cells colocalized with vimentin throughout the retina. CRALBP-IR was detected in differentiated retina and in some proliferating cells. GLAST-IR cells were present only within the differentiated region. Nestin, vimentin and CRALBP each colocalized with mitotic Ki67-IR cells, suggesting that in foetal retina Müller cells and retinal progenitor cells are overlapping populations and that Müller cells are end-stage progenitor cells.  相似文献   
26.
Ha Y  Lee JE  Kim KN  Cho YE  Yoon DH 《Acta neurochirurgica》2003,145(6):483-487
  相似文献   
27.
Many tissues arise from pluripotent stem cells through cell-type specification and maturation. In the bone marrow, primitive stem cells generate all the different types of blood cells via the sequential differentiation of increasingly committed progenitor cells. Cell-surface markers that clearly distinguish stem cells, restricted progenitors, and differentiated progeny have enabled researchers to isolate these cells and to study the regulatory mechanisms of hematopoiesis. Neuronal differentiation appears to involve similar mechanisms. However, neural progenitor cells that are restricted to a neuronal fate have not been characterized in vivo, because specific cell-surface markers are not available. We have developed an alternative strategy to identify and isolate neuronal progenitor cells based on dual-color fluorescent proteins. To identify and isolate directly progenitor cells from brain tissue without the need for either transfection or intervening cell culture, we established lines of transgenic mice bearing fluorescent transgenes regulated by neural promoters. One set of transgenic lines expressed enhanced yellow fluorescent protein (EYFP) in neuronal progenitor cells and neurons under the control of the Talpha1 alpha-tubulin promoter. Another line expressed enhanced green fluorescent protein (EGFP) in immature neural cells under the control of the enhancer/promoter elements of the nestin gene. By crossing these lines we obtained mice expressing both transgenes. To isolate neuronal progenitor cells directly from the developing brain, we used flow cytometry, selecting cells that expressed EGFP and EYFP simultaneously. We expect this strategy to provide valuable material with which to study the mechanisms of neurogenesis and to develop cell-based therapies for neurological disorders.  相似文献   
28.
Cancer stem cell-related (CSC) markers have been suggested to have promising potentials as novel types of prognostic and predictive markers in gliomas. However no single CSC-related marker is currently used in clinical decisions. The aim of this study was to investigate the prognostic value of CD133 and nestin separately and in combination using a novel quantitative approach in a well-characterized population-based cohort of glioma patients. The expression of CD133 and nestin was measured by systematic random sampling in stained paraffin sections from 239 glioma patients diagnosed between 2005 and 2009. We found that the expression of CD133 did not correlate with WHO grade, and there was no association with overall survival (OS). The level of nestin correlated positively with WHO grade. In patients with WHO grade II tumors, a high level of nestin was associated with short progression-free survival (PFS) in multivariate analysis. High levels of co-localization were associated with poor PFS in patients with WHO grade II tumors, but not with OS. We conclude that CD133 was not an independent prognostic factor, but a high level of nestin was associated with poor PFS in patients with WHO grade II tumors. The combination of double-immunofluorescence and automated analysis seems to be a feasible and reproducible approach for investigation of the prognostic potential of biomarkers.  相似文献   
29.
目的 探讨剥夺卵巢雌激素对成年大鼠基底前脑神经元表达Nestin的影响。方法 将健康成年雌性大鼠随机分为正常对照、卵巢切除2周及4周三组,用免疫组化法观察卵巢切除后基底前脑的内侧隔核(MS)、斜角带垂直支(vDB)及水平支(bDB)Nestin免疫反应阳性(Nestin-IR) 神经元的形态和数目变化。结果 卵巢切除2周、4周组MS、vDB及hDB的Neshn-IR神经元形态与正常对照组相比无明显变化;但卵巢切除2周、4周组MS、vDB及hDB的 Nestin-IR神经元的数目与正常对照组相比均有不同程度的减少,尤以hDB的减少最明显(P<0.01,P<0.05)。结论 提示基底前脑Nestin-IR神经元的Neshn表达受卵巢雌激素的影响,hDB的Neshn-IR神经元的表达受此影响更大。  相似文献   
30.
背景:肿瘤干细胞理论认为肿瘤中存在一小部分具有无限增殖潜能和自我更新能力,能够分化为成熟细胞表型的干细胞样细胞,对肿瘤发生、增殖、侵袭起关键作用。目的:建立体外分离、培养与鉴定星形胶质细胞瘤干细胞的方法。方法:采用直接培养法分离培养星形胶质细胞瘤干细胞。参照神经干细胞培养条件,进行体外培养。观察其增殖、分化并进行巢蛋白、CD133免疫细胞化学鉴定和诱导分化后神经元特异性烯醇化酶、胶质纤维酸性蛋白及O4免疫细胞化学鉴定。结果与结论:培养7-10d,可形成大量悬浮生长巢蛋白及CD133免疫阳性的神经球,经诱导分化后细胞呈神经元特异性烯醇化酶、胶质纤维酸性蛋白或O4免疫阳性。提示星形胶质细胞瘤中存在具有神经干细胞特性的肿瘤干细胞。CD133和巢蛋白是星形胶质细胞瘤干细胞重要的表面标记,可以用于星形胶质细胞瘤干细胞的分离。  相似文献   
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