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951.
Stefan Koudstaal Sanne J. Jansen of Lorkeers Johannes M.I.H. Gho Gerardus P.J van Hout Marlijn S. Jansen Paul F. Gründeman Gerard Pasterkamp Pieter A. Doevendans Imo E. Hoefer Steven A.J. Chamuleau 《Journal of visualized experiments : JoVE》2014,(86)
Introduction of newly discovered cardiovascular therapeutics into first-in-man trials depends on a strictly regulated ethical and legal roadmap. One important prerequisite is a good understanding of all safety and efficacy aspects obtained in a large animal model that validly reflect the human scenario of myocardial infarction (MI). Pigs are widely used in this regard since their cardiac size, hemodynamics, and coronary anatomy are close to that of humans. Here, we present an effective protocol for using the porcine MI model using a closed-chest coronary balloon occlusion of the left anterior descending artery (LAD), followed by reperfusion. This approach is based on 90 min of myocardial ischemia, inducing large left ventricle infarction of the anterior, septal and inferoseptal walls. Furthermore, we present protocols for various measures of outcome that provide a wide range of information on the heart, such as cardiac systolic and diastolic function, hemodynamics, coronary flow velocity, microvascular resistance, and infarct size. This protocol can be easily tailored to meet study specific requirements for the validation of novel cardioregenerative biologics at different stages (i.e. directly after the acute ischemic insult, in the subacute setting or even in the chronic MI once scar formation has been completed). This model therefore provides a useful translational tool to study MI, subsequent adverse remodeling, and the potential of novel cardioregenerative agents. 相似文献
952.
Our understanding of the mitochondrial or intrinsic apoptosis pathway and its role in chemotherapy resistance has increased significantly in recent years by a combination of experimental studies and mathematical modelling. This combined approach enhanced the quantitative and kinetic understanding of apoptosis signal transduction, but also provided new insights that systems-emanating functions (i.e., functions that cannot be attributed to individual network components but that are instead established by multi-component interplay) are crucial determinants of cell fate decisions. Among these features are molecular thresholds, cooperative protein functions, feedback loops and functional redundancies that provide systems robustness, and signalling topologies that allow ultrasensitivity or switch-like responses. The successful development of kinetic systems models that recapitulate biological signal transduction observed in living cells have now led to the first translational studies, which have exploited and validated such models in a clinical context. Bottom-up strategies that use pathway models in combination with higher-level modelling at the tissue, organ and whole body-level therefore carry great potential to eventually deliver a new generation of systems-based diagnostic tools that may contribute to the development of personalised and predictive medicine approaches. Here we review major achievements in the systems biology of intrinsic apoptosis signalling, discuss challenges for further model development, perspectives for higher-level integration of apoptosis models and finally discuss requirements for the development of systems medical solutions in the coming years. 相似文献
953.
组织工程技术已被普遍认为是解决组织、器官缺损修复与功能重建的有效手段,它的飞速发展依赖于细胞学、材料学、工程学、临床医学等多学科的交叉渗透.作为组织工程的三大核心,种子细胞、生物材料、组织构建各方面的突破,为组织工程技术的发展奠定了基础.组织工程国家工程中心近年来围绕上述核心开展了系列研究,通过研究胚胎干细胞、成体干细胞、同种异体干细胞、以及发育同源细胞替代的探索,为解决种子细胞来源问题提供了多种选择;生物支架材料的开发,为细胞增殖分化、组织再生提供理想的支持与空间,而生物反应器的开发与应用,进一步提高了组织构建技术,为促进组织的体外形成、重塑和功能成熟创造了条件.在此基础上,开展了大动物体内组织构建和缺损修复的研究,形成了以应用为目标的研究特色,并成功将部分技术应用于临床治疗.本文将对组织工程国家工程中心已有进展做简单介绍并对面临的挑战进行分析. 相似文献
954.
Akatsuki Kokaze Mamoru Ishikawa Naomi Matsunaga Kanae Karita Masao Yoshida Tadahiro Ohtsu Hirotaka Ochiai Takako Shirasawa Hinako Nanri Nobuyuki Saga Iichiro Ohtsu Hiromi Hoshino Yutaka Takashima 《Journal of physiological anthropology》2014,33(1)
Background
Mitochondrial DNA 5178 cytosine/adenine (Mt5178 C/A) polymorphism reportedly modulates the effects of coffee consumption on the risk of hypertension, dyslipidemia and abnormal glucose tolerance. The objective of this analysis was to investigate whether Mt5178 C/A polymorphism modifies the effects of coffee consumption on erythrocytic parameters in male Japanese health check-up examinees.Methods
A total of 436 men (mean age ± standard deviation, 54.1 ± 7.8 years) were selected from among individuals visiting the hospital for regular medical check-ups. After Mt5178 C/A genotyping, an exploratory cross-sectional analysis assessing the joint effects of Mt5178 C/A polymorphism and coffee consumption on red blood cell counts, hematocrit and hemoglobin was conducted.Results
For Mt5178C genotypic men, after adjustment for age, body mass index, alcohol consumption, habitual smoking and green tea consumption, coffee consumption significantly decreased red blood cell counts (P for trend = 0.022) and hemoglobin (P for trend = 0.035). The risk of anemia, defined as hemoglobin of <14 g/dL, after the aforementioned adjustment, appeared to depend on coffee consumption (P for trend = 0.078), and the adjusted odds ratio for anemia was significantly higher in men who consumed ≥4 cups of coffee per day than in those who consumed <1 cup per day (odds ratio = 3.771, 95% confidence interval: 1.088 to 13.06, P = 0.036). For Mt5178A genotypic men, coffee consumption possibly reduced the risk of anemia (P for trend = 0.049). However, after the aforementioned adjustment, the statistical significance disappeared (P for trend = 0.137).Conclusions
This exploratory cross-sectional analysis suggests that Mt5178 C/A polymorphism modulates the effects of coffee consumption on erythrocytic parameters and the risk of anemia in male Japanese health check-up examinees. 相似文献955.
Salim Khan Khanda Jabeen Mirza Fahad Al-Qurainy Malik Zainul Abdin 《Saudi Journal of Biological Sciences》2011,18(3):287-292
In this study “RAPD” molecular marker was employed for the identification of Sennaangustifolia, Sennaacutifolia, Sennatora and Sennasophera. Total 32 decamer primers were screened in amplification with genomic DNA extracted from all species, of which 6 primers yielded species-specific reproducible bands. Out of 42 loci detected, the polymorphic, monomorphic and unique loci were 24, 2 and 16, respectively. Based on dendrogram and similarity matrix, 4 species were differentiated from each other and showed more divergence. Thus, this technique may prove and to contribute the identification of these species of Senna having similar morphology sold in the local markets. 相似文献
956.
Predicting the response to medical therapy and subsequently individualizing the treatment to increase efficacy or reduce toxicity
has been a longstanding clinical goal. Not least within oncology, where many patients fail to be cured, and others are treated
to or beyond the limit of acceptable toxicity, an individualized therapeutic approach is indicated. The mapping of the human
genome and technological developments in DNA sequencing, gene expression profiling, and proteomics have raised the expectations
for implementing genotype-phenotype data into the clinical decision process, but also multiplied the complex interaction of
genetic and other laboratory parameters that can be used for therapy adjustments. Thus, with the advances in the laboratory
techniques, post laboratory issues have become major obstacles for treatment individualization. Many of these challenges have
been illustrated by studies involving childhood acute lymphoblastic leukemia (ALL), where each patient may receive up to 13
different anticancer agents over a period of 2-3 years. The challenges include i) addressing important, but low-frequency
outcomes, ii) difficulties in interpreting the impact of single drug or single gene response data that often vary across treatment
protocols, iii) combining disease and host genomics with outcome variations, and iv) physicians' reluctance in implementing
potentially useful genotype and phenotype data into clinical practice, since unjustified downward or upward dose adjustments
could increase the of risk of relapse or life-threatening complications. In this review we use childhood ALL therapy as a
model and discuss these issues, and how they may be addressed. 相似文献
957.
朝医药是朝鲜民族在长期生活经验中总结出的抵抗病邪的智慧结晶,该医学的核心是四象理论,在治疗上倡导"药乃局限于人"的药性观。鹿茸是鹿科动物梅花鹿或马鹿等雄鹿头上长出的尚未骨化而带毛的幼角,在朝医药中归类于太阴人药,其功效有补肺、补肾阳、益精血等作用,主要用于太阴人的虚劳及气虚证。通过对鹿茸在临床上的应用以及其基础的研究,发现在药物的应用方面上,朝医药与中医药之间有着某些差异,如果探讨两者之差异的根源以及其中关联,那么对药物的基础研究一定会开辟更多的思路并对临床应用也提供更有效的方法。 相似文献
958.
959.
目的:优化白芷中药材有效成分的提取工艺;全面系统地考察与研究市场上白芷中药材的质量。方法:以白芷中欧前胡素和异欧前胡素的含量为指标,采用高效液相色谱法测定,利用正交试验,对渗漉法提取白芷有效成分的工艺条件进行优选;按照《中国药典》2005年版一部白芷项下[含量测定]方法检验了62批次市场上销售的白芷药材中香豆素类物质的含量。结果:乙醇渗漉提取法:药材浸泡24h,加80%乙醇8倍量渗漉,欧前胡素和异欧前胡素的平均提取率为78%;市场上销售的白芷药材中香豆素类物质的含量符合药典的要求。结论:应用渗漉法工艺提取白芷中药材有效成分效率高,稳定性好,适合工业化生产;目前市场上流通的白芷中药材的质量可靠。 相似文献
960.
The future of tissue engineering and cell-based therapies for tissue regeneration will likely rely on our ability to generate functional vascular networks in vivo. In this regard, the search for experimental models to build blood vessel networks in vivo is of utmost importance. The feasibility of bioengineering microvascular networks in vivo was first shown using human tissue-derived mature endothelial cells (ECs); however, such autologous endothelial cells present problems for wide clinical use, because they are difficult to obtain in sufficient quantities and require harvesting from existing vasculature. These limitations have instigated the search for other sources of ECs. The identification of endothelial colony-forming cells (ECFCs) in blood presented an opportunity to non-invasively obtain ECs (5-7). We and other authors have shown that adult and cord blood-derived ECFCs have the capacity to form functional vascular networks in vivo. Importantly, these studies have also shown that to obtain stable and durable vascular networks, ECFCs require co-implantation with perivascular cells. The assay we describe here illustrates this concept: we show how human cord blood-derived ECFCs can be combined with bone marrow-derived mesenchymal stem cells (MSCs) as a single cell suspension in a collagen/fibronectin/fibrinogen gel to form a functional human vascular network within 7 days after implantation into an immunodeficient mouse. The presence of human ECFC-lined lumens containing host erythrocytes can be seen throughout the implants indicating not only the formation (de novo) of a vascular network, but also the development of functional anastomoses with the host circulatory system. This murine model of bioengineered human vascular network is ideally suited for studies on the cellular and molecular mechanisms of human vascular network formation and for the development of strategies to vascularize engineered tissues. 相似文献