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81.
INTRODUCTION: Preeclampsia is a pregnancy-specific syndrome. The immune system in preeclampsia is changed with an increased innate activity and there is a hypothesis of a shift towards Th1-type immunity. The aim of this study was to determine a spectrum of soluble immunological factors denoting different aspects of immune activation in third trimester sera from women with preeclampsia (N=15) and compare with levels in sera from normal pregnant women (N=15). MATERIAL AND METHODS: IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12 p40, IL-13, IL-15, IL-17, IFN-alpha, IFN-gamma, TNF-alpha, GM-CSF, MIP-lalpha, MIP-1beta, MCP-1, eotaxin and RANTES were measured in serum using multiplex bead arrays. The levels of soluble CD14 and soluble IL-4 receptor were measured by enzyme-linked immunoassay (ELISA). RESULTS: Preeclamptic women had significantly increased levels of circulating IL-6 (p=0.002), IL-8 (p=0.003) and soluble IL-4R (p=0.037), compared to women with normal pregnancies. CONCLUSION: This study supports the hypothesis of increased inflammatory responses in preeclampsia, illustrated by the increased levels of IL-6 and IL-8. The finding of increased levels of soluble IL-4 receptor is an intriguing finding with several interpretations, which may partly support the hypothesis of a Th1 shift in preeclampsia.  相似文献   
82.
The aim of this study was to assess whether enzymatically isolated chondrons from normal adult articular cartilage could be used as a model for the onset of osteoarthritis, by comparison with mechanically extracted chondrons from osteoarthritic cartilage. Enzymatically isolated chondrons (EC) were cultured for 4 weeks in alginate beads and agarose gel constructs. Samples were collected at days 1 and 2, and weekly thereafter. Samples were immunolabelled for types II and VI collagen, keratan sulphate and fibronectin and imaged using confocal microscopy. Mechanically extracted chondrons (MC) were isolated, immunohistochemically stained for type VI collagen and examined by confocal microscopy. In culture, EC showed the following characteristics: swelling of the chondron capsule, cell division within the capsule and remodelling of the pericellular microenvironment. This was followed by chondrocyte migration through gaps in the chondron capsule. Four types of cell clusters formed over time in both alginate beads and agarose constructs. Cells within clusters exhibited quite distinct morphologies and also differed in their patterns of matrix deposition. These differences in behaviour may be due to the origin of the chondrocytes in the intact tissue. The behaviour of EC in culture paralleled the range of morphologies observed in MC, which presented as single and double chondrons and large chondron clusters. This preliminary study indicates that EC in culture share similar structural characteristics with MC isolated from osteoarthritic cartilage, confirming that some processes that occur in osteoarthritis, such as pericellular remodelling, take place in EC cultures. The study of EC in culture may therefore provide an additional tool to investigate the mechanisms operating during the initial stages of osteoarthritis. Further investigation of specific osteoarthritic phenotype markers will, however, be required in order to validate the value of this model.  相似文献   
83.
Hepatocellular carcinoma (HCC) is one of the most frequent and deadliest cancers worldwide. Liver transplantation, surgical resection or local ablation offer the best survival advantages but most patients either present when the tumor is in an advanced stage or the degree of underlying liver disease precludes these options. Several therapies have been proposed for these patients with proven survival benefits. These therapies comprise the locoregional treatment for HCC, and include percutaneous ethanol injection (PEI), radiofrequency ablation (RFA), transarterial chemoembolization (TACE), transarterial radioembolization (TARE), and drug-eluting bead (DEB). PEI and RFA are considered curative treatments for early stage HCC; whereas TACE is a standard of care for intermediate stages. Additionally, evaluation of response to locoregional treatment in HCC is important, as objective response may become a surrogate marker for improved survival. Currently, there are several criteria for response assessment, including the World Health Organization (WHO), the Response Evaluation Criteria in Solid Tumors (RECIST), the European Association for the Study of the Liver Criteria (EASL), and the modified RECIST (mRECIST); however, there has been poor correlation between the clinical benefit provided by locoregional interventional therapies and conventional methods of response assessment.The aim of our study was to review and analyze the current evidence for radiological interventions in HCC, and to propose evidence based recommendations to improve the management of these patients.  相似文献   
84.
Zhang M  Wu N  Yang L  Zhang J  Sun X  Zhong S  Ma X  Wang Y 《The Journal of dermatology》2011,38(12):1158-1162
Herpes zoster (HZ) is a Varicella zoster virus infection disease. Previous studies have presumed the connection between development of HZ and involvement of cellular immunity in peripheral blood. However, whether cellular immunity plays a role in the local skin lesion has not been addressed. To explore the levels of T-helper cell (Th)1/Th2 type cytokine profiles in the blister fluid of the skin lesions from the patients with HZ and its role in pathogenesis, we used the cytometric bead array kit to compare the levels of cytokines (interleukin [IL]-2, tumor necrosis factor [TNF]-α, IL-10 and IL-4) in blister fluid from 46 patients with those from the suction blister fluids from 20 volunteers without any infectious disease (the control group). The results indicated that the levels of Th1 cytokines, IL-2 and TNF-α in the blister fluid from the patients' skin lesions were significantly lower than those from the control group, whereas the levels of Th2 cytokines IL-10 and IL-4 were significantly higher than those in the control group. Moreover, significant variation of the levels of Th1/Th2 cytokines (IL-2, TNF-α, IL-10 and IL-4) in the blister fluid from the HZ patients' lesions was also observed among different stages of the disease. It is concluded that a cytokine imbalance was present in the local lesions of patients with HZ during disease development. Our data suggested that the Th immunity was associated with disease activity, which may play an important role in the pathogenesis of HZ.  相似文献   
85.
 目的:用改良的培养基培养人心肌干细胞,并筛选鉴定。方法: 通过心脏外科手术取下右心耳组织,用组织块培养法来获得原代心肌干细胞,用改良的心肌干细胞培养液培养,增殖传代后进行心肌干细胞表面标志物的鉴定,再用免疫磁珠筛选以获得较纯的目的心肌干细胞。结果: 培养约2周后,贴壁良好的心肌组织块周围可见有小、圆、亮的细胞爬出,用Accutase(细胞消化液)短时间消化后冲洗细胞,培养增殖传代,其增殖能力与传统心肌干细胞培养液培养的细胞比较无显著差异,用流式细胞术鉴定c-Kit(干细胞表面标志物),其阳性率(6.8±2.1)%,之后用含抗c-Kit抗体(anti-c-Kit)的磁珠进行分选,即得较纯的c-Kit阳性(c-Kit+)心肌干细胞,它们可以分化为心肌细胞。结论: 通过心脏组织块贴壁培养法,用改良后的心肌干细胞培养基培养,再借助免疫磁珠的分选,同样可得到较纯的c-Kit+心肌干细胞。  相似文献   
86.
87.
Selective laser melting (SLM) produces a near-net-shaped product by scanning a concentrated high-power laser beam over a thin layer of metal powder to melt and solidify it. During the SLM process, the material temperature cyclically and sharply rises and falls. Thermal analyses using the finite element method help to understand such a complex thermal history to affect the microstructure, material properties, and performance. This paper proposes a novel calibration strategy for the heat source model to validate the thermal analysis. First, in-situ temperature measurement by high-speed thermography was conducted for the absorptivity calibration. Then, the accurate simulation error was defined by processing the cross-sectional bead shape images by the experimental observations and simulations. In order to minimize the error, the optimal shape parameters of the heat source model were efficiently found by using Bayesian optimization. Bayesian optimization allowed us to find the optimal parameters with an error of less than 4% within 50 iterations of the thermal simulations. It demonstrated that our novel calibration strategy with Bayesian optimization can be effective to improve the accuracy of predicting the temperature field during the SLM process and to save the computational costs for the heat source model optimization.  相似文献   
88.
腺样囊性癌细胞系中肿瘤干细胞的生物学特性初探   总被引:4,自引:0,他引:4  
目的:对腺样囊性癌细胞系ACC-2中不同表型的肿瘤细胞生物学特性进行分析和研究,为肿瘤干细胞学说提供实验依据。方法:采用单细胞体外培养法,了解腺样囊性癌细胞(ACC-2)的分裂、增殖特点;采用免疫组化方法,检测ACC-2细胞表面CD44和CD24表达的差异性;应用免疫磁珠技术,分离不同表型的ACC-2细胞后,以裸鼠成瘤试验了解不同表型ACC-2细胞的成瘤能力。采用SPSS10.0统计软件包对所得数据进行X~2检验。结果:体外单细胞培养的ACC-2,仅有4.5%可持续分裂、增殖。CD44-和CD44 /CD24 细胞在体外培养条件下均无长期存活能力。不同表型的ACC-2动物成瘤试验结果显示,CD44 /CD24-亚群的ACC-2细胞最低成瘤接种细胞数显著低于常规ACC-2细胞,CD44-和CD44 /CD24 细胞则均无成瘤能力。免疫组化染色证实,CD44 /CD24-肿瘤细胞具有分化为其他表型肿瘤细胞的能力。结论:细胞表面抗原为CD44 CD24-的肿瘤细胞仅占ACC-2肿瘤细胞的极少部分,这些细胞具有极强的增殖能力和分化为其他表型肿瘤细胞的能力。ACC-2肿瘤细胞的增殖和成瘤能力源于CD44 / CD24-细胞亚群。未分离的ACC-2细胞与CD44 /CD24-ACC-2细胞在与细胞分化、凋亡、黏连、信号传导等有关的基因上存在差异。提示ACC-2中存在肿瘤干细胞,而CD44 /CD24-是ACC-2肿瘤干细胞必须兼备的表面标志。  相似文献   
89.
高梯度磁场免疫磁珠法分离人表皮Langerhans细胞   总被引:3,自引:0,他引:3  
采用鼠抗人 OKT6单克隆抗体与包被羊抗鼠 Ig G免疫磁珠的特异性结合 ,利用钢毛产生高梯度磁场 ,进行免疫磁珠法分离纯化人表皮 L C。结果表明 LC纯化率超过 99% ,细胞活性超过 95%。该方法简单、快速、价廉、纯化率高 ,不受样本量的限制 ,易在无菌下分离纯化 ,为国内首次报道  相似文献   
90.
目的 评价两种免疫磁性纳米探针(Anti-Sp17-Silane@MNPs和Anti-Sp17-CS@MNPs)对小鼠体内肿瘤MRI的靶向效果.方法 分别将硅烷和壳聚糖修饰的磁性纳米粒与抗Sp17单克隆抗体交联,形成两种免疫磁性纳米探针(Anti-Sp17-Silane@MNPs和Anti-Sp17-CS@MNPs),对荷瘤裸鼠注射后进行MR扫描,并解剖实验鼠,取器官组织(肺、肝和肿瘤)进行普鲁士蓝染色,观察铁粒子聚集情况.结果 两种探针注射2 h后,肿瘤感兴趣区均可见T2信号明显降低,Anti-Sp17-CS@MNPs组降低更为显著.组织学检查见Anti-Sp17-Silane@MNPs注射组在肺、肝均有明显铁粒子聚集,而Anti-Sp17-CS@MNPs注射组各个器官组织铁粒子非特异聚集明显减少.结论 MRI中, 对于小鼠体内肿瘤,Anti-Sp17-CS@MNPs探针比Anti-Sp17-Silane@MNPs特异性更好.  相似文献   
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