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211.
The effects of primary tumors on the host systemic environment and resulting contributions of the host to tumor growth are poorly understood. Here, we find that human breast carcinomas instigate the growth of otherwise-indolent tumor cells, micrometastases, and human tumor surgical specimens located at distant anatomical sites. This systemic instigation is accompanied by incorporation of bone-marrow cells (BMCs) into the stroma of the distant, once-indolent tumors. We find that BMCs of hosts bearing instigating tumors are functionally activated prior to their mobilization; hence, when coinjected with indolent cells, these activated BMCs mimic the systemic effects imparted by instigating tumors. Secretion of osteopontin by instigating tumors is necessary for BMC activation and the subsequent outgrowth of the distant otherwise-indolent tumors. These results reveal that outgrowth of indolent tumors can be governed on a systemic level by endocrine factors released by certain instigating tumors, and hold important experimental and therapeutic implications.  相似文献   
212.
魏家窝铺遗址位于内蒙古赤峰市红山区文钟镇魏家窝铺村,是一处大型的红山文化中期环壕聚落遗址。在2009-2011年发掘出土的陶器中,许多平底器类标本内壁表面都发现有细腻的黑色灰烬,我们对这些灰烬和几件不含灰烬的陶器标本进行了植物残留物提取和鉴定,从六份样品中观测到了植物淀粉粒,这些淀粉粒可根据形态分为四种类型,分别代表了禾本科、植物地下储藏器官、疑似坚果的植物种类和未知种类。大量的禾本科淀粉粒在形态上与粟类(小米)淀粉粒极为相似,加之遗址中出土的大量炭化粟,我们推测,这些陶罐中的黑色灰烬为内部盛装的粟炭化分解所致,这些陶器正是红山文化中的食物储藏器。存在的其他类型淀粉粒表明,尽管魏家窝铺遗址出土的植物遗存已显示了较为确凿的农业经济,但采集经济也仍占有重要地位。  相似文献   
213.
Hemangioendotheliomas can express type 3 iodothyronine deiodinase and cause severe hypothyroidism. The risk of congenital malformations such as vertebral and cardiac abnormalities in infants of diabetic mothers is higher than in babies of healthy women. Here we report an infant of a diabetic mother with hypothyroidism caused by liver hemangioendothelioma. Consumptive hypothyroidism should be an indicator to search for a vascular tumor in infants. Supranormal doses of L-thyroxine might be required for normalization of thyroid function until the tumor involutes or is resected.  相似文献   
214.
Apricot stones were carbonised and activated after treatment with sulphuric acid (1:1) at 200 degrees C for 24 h. The ability of the activated carbon to remove Ni(II), Co(II), Cd(II), Cu(II), Pb(II), Cr(III) and Cr(VI) ions from aqueous solutions by adsorption was investigated. Batch adsorption experiments were conducted to observe the effect of pH (1-6) on the activated carbon. The adsorptions of these metals were found to be dependent on solution pH. Highest adsorption occurred at 1-2 for Cr(VI) and 3-6 for the rest of the metal ions, respectively. Adsorption capacities for the metal ions were obtained in the descending order of Cr(VI) > Cd(II) > Co(II) > Cr(III) > Ni(II) > Cu(II) > Pb(II) for the activated carbon prepared from apricot stone (ASAC).  相似文献   
215.
Mitochondrial involvement in amyotrophic lateral sclerosis   总被引:8,自引:0,他引:8  
The causes of motor neuron death in amyotrophic lateral sclerosis (ALS) are so far unknown. The involvement of mitochondria in the disease was initially suggested by ultrastructural studies. More recently these observations have been supported by studies of mitochondrial function in ALS. Alterations in the activity of complexes which make up the mitochondrial electron transport chain have been recorded as well as mutations in the mitochondrial genome. The calcium buffering function of the mitochondria may also be affected in the disease. This review will discuss how mitochondrial dysfunction could be of relevance in ALS and the evidence that an alteration of mitochondrial function is a feature of the disease. The way in which the involvement of mitochondria fits with other aetiological hypotheses for ALS will also be discussed.  相似文献   
216.
217.
目的:回顾分析各种非小细胞肺癌(non-small cell lung cancer,NSCLC)的治疗方案及影响其治疗预后的因素,为合理制定个体化的综合治疗方案提供参考。方法:回顾分析近年来NSCLC治疗的研究报道,分析如病理分期、实验室检查结果(VEGF、WBC、Hg等)影响治疗预后的因素,建议相应的治疗对策。结果:1.Ⅰ期、Ⅱ期及部分Ⅲa期NSCLC的患者治疗措施首先以手术治疗为主,同步放化疗比单纯放、化疗及序贯放化疗更能有效改善晚期NSCLC的预后;2.个体相关因素、肿瘤相关因素和治疗相关因素影响NSCLC治疗预后。结论:同步放化疗在晚期NSCLC的治疗中有重要作用,肿瘤的病理分期、血浆VEGF浓度是影响NSCLC预后的独立因素。  相似文献   
218.
Autologous bone marrow cell transplantation (BMCs-Tx) is a promising novel option for treatment of cardiovascular disease. We analysed in a randomized controlled study the influence of the intracoronary autologous freshly isolated BMCs-Tx on the mobilization of bone marrow-derived circulating progenitor cells (BM-CPCs) in patients with acute myocardial infarction (AMI). Sixty-two patients with AMI were randomized to either freshly isolated BMCs-Tx or to a control group without cell therapy. Peripheral blood (PB) concentrations of CD34/45(+) - and CD133/45(+)-circulating progenitor cells were measured by flow cytometry in 42 AMI patients with cell therapy as well as in 20 AMI patients without cell therapy as a control group on days 1, 3, 5, 7, 8 and 3, 6 as well as 12 months after AMI. Global ejection fraction (EF) and the size of infarct area were determined by left ventriculography. We observed in patients with freshly isolated BMCs-Tx at 3 and 12 months follow up a significant reduction of infarct size and increase of global EF as well as infarct wall movement velocity. The mobilization of CD34/45(+) and CD133/45(+) BM-CPCs significantly increased with a peak on day 7 as compared to baseline after AMI in both groups (CD34/45(+): P < 0.001, CD133/45(+): P < 0.001). Moreover, this significant mobilization of BM-CPCs existed 3, 6 and 12 months after cell therapy compared to day 1 after AMI. In control group, there were no significant differences of CD34/45(+) and CD133/45(+) BM-CPCs mobilization between day 1 and 3, 6 and 12 months after AMI. Intracoronary transplantation of autologous freshly isolated BMCs by use of point of care system in patients with AMI may enhance and prolong the mobilization of CD34/45(+) and CD133/45(+) BM-CPCs in PB and this might increase the regenerative potency after AMI.  相似文献   
219.
An enigma in the field of peptide transport is the structural basis for ligand promiscuity, as exemplified by PepT1, the mammalian plasma membrane peptide transporter. Here, we present crystal structures of di‐ and tripeptide‐bound complexes of a bacterial homologue of PepT1, which reveal at least two mechanisms for peptide recognition that operate within a single, centrally located binding site. The dipeptide was orientated laterally in the binding site, whereas the tripeptide revealed an alternative vertical binding mode. The co‐crystal structures combined with functional studies reveal that biochemically distinct peptide‐binding sites likely operate within the POT/PTR family of proton‐coupled symporters and suggest that transport promiscuity has arisen in part through the ability of the binding site to accommodate peptides in multiple orientations for transport.  相似文献   
220.
Gamma interferon (IFN-γ) regulates immune defenses against viruses, intracellular pathogens, and tumors by modulating cell proliferation, migration, invasion, and vesicle trafficking processes. The large GTPase guanylate binding protein 1 (GBP-1) is among the cellular proteins that is the most abundantly induced by IFN-γ and mediates its cell biologic effects. As yet, the molecular mechanisms of action of GBP-1 remain unknown. Applying an interaction proteomics approach, we identified actin as a strong and specific binding partner of GBP-1. Furthermore, GBP-1 colocalized with actin at the subcellular level and was both necessary and sufficient for the extensive remodeling of the fibrous actin structure observed in IFN-γ-exposed cells. These effects were dependent on the oligomerization and the GTPase activity of GBP-1. Purified GBP-1 and actin bound to each other, and this interaction was sufficient to impair the formation of actin filaments in vitro, as demonstrated by atomic force microscopy, dynamic light scattering, and fluorescence-monitored polymerization. Cosedimentation and band shift analyses demonstrated that GBP-1 binds robustly to globular actin and slightly to filamentous actin. This indicated that GBP-1 may induce actin remodeling via globular actin sequestering and/or filament capping. These results establish GBP-1 as a novel member within the family of actin-remodeling proteins specifically mediating IFN-γ-dependent defense strategies.  相似文献   
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