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1.

Background and aims

It has been previously verified that mesenchymal stromal cells (MSCs) have a good therapeutic effect on severe acute pancreatitis (SAP) and the potential for regeneration of damaged pancreatic tissue, but the exact molecular mechanism remains unclear. In this study, we demonstrated the therapeutic effect of bone morrow MSCs (BMSCs) on SAP, probably by targeting heme oxygenase-1 (HO-1).

Methods

Six hours after SAP induction, either phosphate-buffered saline (PBS) or BMSCs were transfused into the caudal vein of rats, zinc protoporphyrin (ZnPP) was administered intraperitoneally. Pancreatic pathological scoring, serum levels of amylase and inflammatory factors, as well as levels of reactive oxygen species (ROS), malondialdehyde (MDA) and myeloperoxidase (MPO), superoxide dismutase (SOD) and catalase (CAT) activity in the pancreas were evaluated.

Results

Our data showed that BMSCs significantly reduce inflammation and oxidative stress, reduce apoptosis and promote angiogenesis of damaged pancreas. Moreover, BMSCs increased the level of HO-1 in the serum and pancreatic tissue in rats with SAP. In addition, the protective effect of BMSCs was partially neutralized by the HO-1 activity inhibitor ZnPP, suggesting a key role of HO-1 in the therapeutic effect of BMSCs on SAP.

Conclusions

BMSCs ameliorated SAP, probably by inducing expression of HO-1, which can exert anti-inflammatory and anti-oxidant effects, reduce apoptosis and promote angiogenesis.  相似文献   
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3.
A note on a test for Poisson overdispersion   总被引:3,自引:0,他引:3  
HNING  DANKMAR BO 《Biometrika》1994,81(2):418-419
  相似文献   
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5.
In situPCR on Plant Material with Sub-cellular Resolution   总被引:4,自引:0,他引:4  
JOHANSEN  BO 《Annals of botany》1997,80(5):697-700
In situPCR and reverse transcribedin situPCR have been testedon leaves of sugar cane fixed in FAA, 4% PFA or 2% PFA+2.5%GA.In situPCR amplification of the gene coding for ribulose-1,5-bisphosphatecarboxylase/oxygenase (rbcL) was successfully performed followingall three fixation protocols. As expected the PCR product wasrestricted to the plastids of all cells. Reverse transcribedinsituPCR was performed onrbcL mRNA and in this case the PCR productwas restricted to the plastids of the bundle sheath cells. Thisis the first report ofin situPCR on plant material and onlythe second report ofin situPCR with sub-cellular resolution.InsituPCR onrbcL may prove to be a valuable positive control forfuturein situPCR studies on plant material.Copyright 1997 Annalsof Botany Company In situPCR; reversed transcribedin situPCR; rbcL; C4-plants  相似文献   
6.
廖永伯  张琪  丁金凤 《生理学报》1991,43(4):368-375
培养的卒中型自发性高血压大鼠(SHR_(sp))及其对照 WKY 大鼠主动脉平滑肌细胞(VSMC)上存在心房钠尿肽(ANP)的特异性受体,它们与~(125)I-ANP 的最大结合量(B_(max))是:SHR_(sp)3.65±0.13和 WKY 1.89±0.09 pmol/mg pr(P<0.01);解离平衡常数(Kd)值分别是72.6±10.2和42.0±4.8×10~(-12)mol/L(P<0.01)。 两种细胞内介导舒血管作用的第二信使、环磷酸乌苷(cGMP)的基础浓度无显著差异,对相同剂量 ANP 刺激引起 cGMP 分别增加139(SHRsp)和271(WKY)倍。可见 SHRsp 的 VSMC ANP 受体数量虽比 WKY大鼠增多,但对相同剂量 ANP 引起的 cGMP 增加反应及 ANP 受体的亲和力均显著降低。高盐培养液孵育24h 后,细胞表面 ANP 受体的亲和力改变不明显,但受体数量下调,SHRsp 和 WKY 大鼠分别降至对照的34.8±8.2%和38.6±9.4%,细胞对 ANP 引起的 cGMP增加反应明显降低,且均以 SHR_(sp)较显著。提示后两种变化可能在高盐促进血压升高的机制中起作用。  相似文献   
7.
    
Cyanobacterial mats collected in hypersaline salterns were incubated in a greenhouse under low sulphate concentrations ([]) and examined for their primary productivity and emissions of methane and other major carbon species. Atmospheric greenhouse warming by gases such as carbon dioxide and methane must have been greater during the Archean than today in order to account for a record of moderate to warm palaeoclimates, despite a less luminous early sun. It has been suggested that decreased levels of oxygen and sulphate in Archean oceans could have significantly stimulated microbial methanogenesis relative to present marine rates, with a resultant increase in the relative importance of methane in maintaining the early greenhouse. We maintained modern microbial mats, models of ancient coastal marine communities, in artificial brine mixtures containing both modern [] (c. 70 mm ) and ‘Archean’[] (<0.2 mm ). At low [], primary production in the mats was essentially unaffected, while rates of sulphate reduction decreased by a factor of three, and methane fluxes increased by up to 10‐fold. However, remineralization by methanogenesis still amounted to less than 0.4% of the total carbon released by the mats. The relatively low efficiency of conversion of photosynthate to methane is suggested to reflect the particular geometry and chemical microenvironment of hypersaline cyanobacterial mats. Therefore, such mats were probably relatively weak net sources of methane throughout their 3.5 Ga history, even during periods of low environmental levels oxygen and sulphate.  相似文献   
8.
Prosopis flexuosa is an arboreal Leguminosae that grows in arid and semiarid temperate zones of Argentina, in the Monte eco-region. It is a promising native forest species for recovering arid and semiarid regions because it plays an important role in erosion control as well as in soil fertility. Furthermore, it provides diverse economical resources. The main challenge to the forestry sector is finding a balance between production and forest protection. For this purpose, it is necessary to gather information about genetic parameters. In this study, we measured the distribution of the variation of 14 quantitative traits in an experimental half-sib stand, where families are representative of hierarchically structured populations. We applied a multivariate extension of the classical Q ST –F ST neutrality test to determine the relative importance of drift versus selection in the distribution of genetic variability. We found strong evidence that different selective regimes act on different traits and that selection favors different optima in each sampling site. The selection to different optima is much stronger among than within provenances. This result helps explain the possible causes for the regional variation observed in P. flexuosa and to define the management units and the evolutionarily significant units for this species.  相似文献   
9.
植物miRNA在调控基因表达、细胞周期、生物体发育、抗逆等方面起重要作用。为研究胡杨(Populus euphratica Oliv.)的耐盐机制,以1年生胡杨无性系幼苗为材料,构建具有空间代表性的盐胁迫胡杨cDNA文库,利用二代测序技术测定NaCl胁迫下和正常培养条件下胡杨叶和根miRNA表达情况。结果表明,不同的miRNA之间表达量存在明显差异,表达丰度最高的miRNA有miR156、miR157、miR165、miR166和miR167等,合计占总表达量的90%以上。胡杨根部存在特异表达的miRNA,在整个耐盐调控机制中发挥着生理调节、分子调控和信号传导等极为重要的作用。盐处理样品中发现大量响应盐胁迫的miRNA,对这些转录因子进行靶基因预测和注释后,发现很多盐胁迫响应的miRNA与NAC和SPL等重要转录因子家族相关,与前人的结论一致,另外还发现许多miRNA的调控对象是ATP酶和激素响应因子。  相似文献   
10.
环境温度的变化影响野生啮齿动物的消化道形态与功能。小肠是吸收营养成分的主要部位,其结构和功能具有可塑性。为了解小肠黏膜的结构和功能对环境温度变化的响应机制,以布氏田鼠为研究对象,比较了低温组和常温组动物小肠黏膜的组织结构和小肠黏膜免疫相关细胞的数目。结果显示:(1)低温组布氏田鼠的十二指肠、空肠和回肠的绒毛长度及绒毛长度与隐窝深度的比值均高于对照组;(2)低温驯化使布氏田鼠小肠上皮内淋巴细胞的数量增加;(3)低温驯化使布氏田鼠十二指肠、空肠和回肠的杯状细胞数量均显著增加。结果表明,在低温环境下布氏田鼠的小肠黏膜结构和免疫细胞的数量发生了可塑性变化,这可能与低温环境下的高能量需求和免疫功能的变化有关。  相似文献   
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