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151.
Jing-Ya Zeng Jing-Jing Du Ying Pan Jian Wu Hai-Liang Bi Bao-Hong Cui Tai-Yu Zhai Yong Sun Yi-Hua Sun 《International journal of molecular sciences》2016,17(9)
Acute myocardial infarction (AMI) is a condition triggered by an inflammatory process that seriously affects human health. Calcium-sensing receptor (CaSR) in T lymphocytes is involved during the inflammation reaction. However, the relationship between them is not very clear. In this study, we collected human peripheral blood T lymphocytes from patients with AMI and in different stages of percutaneous coronary intervention (PCI) (at the onset of AMI, the first day after PCI (PCI-1), PCI-3, and PCI-5) to study the CaSR and NF-κB pathway protein expression, cytokine release and T cell apoptosis. The results showed that the expressions of CaSR, P-p65, Caspase-12, and the secretions of Th-1 and Th-2 type cytokines were increased at the onset of AMI, especially on the PCI-1. Meanwhile, the apoptosis rate of CD3+, CD4+ and CD8+ T lymphocytes also increased. However, from PCI-3, all the indicators began to decline. In addition, we also found that positive CaSR small interfering RNA (siRNA) transfection in T lymphocytes and NF-κB pathway blocker Bay-11-7082 reversed the increased expressions of CaSR, P-p65, Caspase-12, reduced the secretions of Th-1 and Th-2 type cytokines, and decreased T lymphocytes apoptosis rate not only in the AMI patients but also in the normal controls. All of these results indicated that CaSR in the human peripheral blood T lymphocytes were involved in the AMI onset and progression, which probably was related to the NF-κB pathway. Our study demonstrated the relationship between AMI and CaSR, and will provide new effective prevention theory and new targets for drug treatment. 相似文献
152.
B‐lymphocyte activation plays an important role in humoral immune system, and its process has been studied well in vivo and in vitro. However, the ultrastructure and adhesion property changes remain unclear. In this study, changes in the morphology and mechanical properties of human peripheral blood B lymphocytes were first studied by atomic force microscopy (AFM). B lymphocytes were treated with the mitogen, pokeweed mitogen (PWM), and Staphylococcus aureus Cowan strain I (SAC) for 24 hr. After B lymphocyte is stimulated by the mitogen, the cell height, diameter, and volume are changed in different degree. The ultrastructure of the B lymphocytes membrane obviously displayed proteins gathering, corresponding with larger changes of average roughness and mean height of particles on cell membrane. Meanwhile, we detected the adhesion force of B lymphocytes after being stimulated by PWM and SAC. We found that the treated cells had a higher adhesion force of 304.16 ± 60.30 pN (PWM) and 249.63 ± 58.03 pN (SAC) than that of control group (104.28 ± 21.77 pN). Therefore, our results could provide new information to further understand the B‐lymphocyte activation process and their structure‐function analyses. SCANNING 34: 60–67, 2012. © 2011 Wiley Periodicals, Inc. 相似文献
153.
以水解度为指标,优化了中性蛋白酶酶解鸡胸软骨Ⅱ型胶原的条件,在此基础上制备不同水解度Ⅱ型胶原酶解复合物,并以淋巴细胞增殖率为指标对其免疫活性进行研究。结果表明,中性蛋白酶的酶解能力最强,其最佳酶解条件为:酶解温度50 ℃、pH 7.5、底物质量浓度25 mg/mL、加酶量40 U/mg、酶解时间150 min。当Ⅱ型胶原在水解度为18%时,其对淋巴细胞的增殖活性达到58.69%。Ⅱ型胶原酶解复合物的质量浓度对淋巴细胞的增殖率也有显著影响,当其质量浓度达到1 mg/mL时,对淋巴细胞增殖能力达到最大。免疫活性较高的Ⅱ型胶原酶解复合物的分子质量主要分布于1 000~180 D范围内,占其总含量的75.21%。 相似文献
154.
Introduction: The aim of this study was to compare reaction of quiescent and proliferating PHA (mitogenic lectin phytohemagglutinin)-stimulated human peripheral blood mononuclear cells (PBMCs) to γ-radiation (IR) and analyze changes of proteins related to repair of DNA damage and apoptosis, such as γH2A.X, p53 and its phosphorylations on serine 15 and 392, and p21. Materials and methods: PBMC were acquired from venous blood of normal donors by centrifugation over Histopague. The lymphocytes were cultured in IMDM medium suplemented with 20% fetal calf serum and antibiotics. For mitogenic stimulation of lymphocytes was added 10 μg/ml PHA. The viability of the PBMC has been identified by flow cytometry. Western blotting has been used for p53 and its phosphorylation form, p21 and H2AX detection. T-lymphocytes and PBMC were irradiated and lysed. To enhance detection sensitivity the Total p53 and PathScan p53ser15 Sandwich ELISA Kits were used. Results: PBMCs were stimulated to enter the cell cycle by treatment with the PHA. After 72 h long stimulation by PHA 96 % of CD3+cells were CD25+ and 12 % entered cell cycle (S+ and G2 phase). PHA-stimulation itself causes increase in γH2A.X, p53, and p21, but not phosphorylation of p53. After the irradiation of these stimulated PBMCs we detected increase in p53 and its phosphorylations on serine 15 and 392, and further increase in p21 from 4 h after the irradiation. Also level of γH2A.X increased significantly. Increase of p53 phosphorylation on serine 15 is dose-dependent 4 h after the irradiation in the whole studied dose range (0.5-7.5 Gy) in stimulated PBMCs. We compared p53, p53ser15 and ser392, p21 and H2AX between grouply of phytohemaglutinin-stimulated and non-stimulated PBMC 4 hours after 0,5-7,5Gy as well as 1-72 hours after 4Gy irradiation.. We were unable to detect p53 accumulation or phosphorylation in response unstimulated PBMC to gamma radiation induced DNA damage. We induced cell cycling by phytohemaglutinin in the T-cell fraction of PMBC preparations. Althougly total p53 protein expression was unchanged after 4 Gy irradiation, we found p53ser392 time-dependent expression (1-72 hours, 4 Gy) and p53ser15 dose-dependent expression in range of 0,5-7,5 Gy 4 hours after irradiation in phytohemaglutinin- stimulated PBMC. Neither total p53 protein nor p53ser392 was not altered by irradiation in non-stimulated PBMC. Conclusions: We suggested that p53 protein accumulation is a common mechanism for induction apoptosis of irradiated cells. We suggest that this pathway is activated in proliferating lymphocytes, unlike quiescent lymphocytes. https://doi.org/10.1051/radiopro:2008665 相似文献
155.
徐林 《水利水运工程学报》2017,15(8)
【】目的 评估中性粒细胞淋巴细胞比值对急性心肌梗死的临床价值。方法选取在我院住院的AMI和冠心病患者,所有患者均行冠状动脉造影,分为AMI组和冠心病组,比较两组患者基线资料,分析中性粒细胞淋巴细胞比值与急性心肌梗死的关系。 结果 ①与冠心病组相比,AMI组患者的Neu水平(t= -10.501,P<0.01)及NLR水平(t=--10.695,P<0.01)明显升高,Lym水平(t= 2.603,P=0.01)明显降低,具有统计学差异;②急性心肌梗死发生的多元logistic回归分析示,NLR是急性心肌梗死发生的危险因素(OR:2.116,95%CI:1.313-3.411,P=0.002);③PLR取3.528作为预测患者发生急性心肌梗死的临界值时,曲线下面积0.869[95%CI:0.824-0.915],灵敏性为0.831,特异性为0.771,P<0.01。结论 NLR与急性心肌梗死有关,可以预测急性心肌梗死的发生。 相似文献
156.
针对传统的两种糖基化接枝方法和改进方法从糖基化反应程度进行系统比较,并对产物氨基酸组成进行分析,以期进一步揭示蛋白质糖基化方法对于糖基化反应过程及产物的影响机制。本文利用干热法、湿热法和加压辅助湿热三种糖基化方法,对大豆7S球蛋白和葡聚糖的糖基化产物从反应程度、氨基酸组成等方面进行研究发现,结果表明:三种制备方法的反应程度高低顺序依次为:湿热法>加压辅助湿热法>干热法,说明压力能够对Maillard反应的进行具有一定的抑制作用,可以控制反应向理想阶段进行。大豆7S球蛋白和葡聚糖的糖基化主要发生在蛋白质肽链上的赖氨酸和精氨酸侧链上的自由氨基,干热法与其它两种方法相比糖链更有易于和精氨酸侧链上的自由氨基发生共价交联,而湿热法和加压辅助湿热法相比糖链更易于和赖氨酸侧链上的自由氨基发生共价交联。 相似文献
157.
目的:探讨托珠单抗与依那西普治疗多关节炎型幼年特发性关节炎(polyarticular juvenile idiopathic arthritis,pJIA)患儿的临床疗效,免疫调节作用及安全性差异。方法:选择2017年1月至2019年3月在浙江大学医学院附属儿童医院诊治的24例重度活动性pJIA患儿,分为托珠单抗组12例和依那西普组12例,分别记录两组患儿治疗前、治疗3个月、6个月、12个月时的临床症状、实验室指标及不良反应情况,并进行对比分析。结果:治疗3个月时,托珠单抗组和依那西普组的关节肿胀数、关节压痛或活动时疼痛数、C反应蛋白(CRP)、红细胞沉降率(ESR)及JADAS 27评分均较治疗前有明显改善(P<0.05);且托珠单抗组的CRP、ESR、JADAS 27评分比依那西普组下降更明显(P<0.05)。治疗6个月时,托珠单抗组CD19+B、CD4+T细胞比例、IgG、IgA、IgM、C3、C4下降和CD8+T细胞比例升高,比较治疗前差异有统计学意义;依那西普组IgG和IgA较治疗前明显下降;托珠单抗组IgG、IgA、IgM、C3、C4比依那西普组下降更明显(P<0.05)。治疗12个月时,托珠单抗组和依那西普组的JADAS 27低疾病活动度率分别为36.4%和37.5%;两组的ACR Pedi 30/50/70/90分别达到100%/100%/87.5%/62.5%和100%/100%/81.9%/45.5%的缓解。两组患儿的不良反应最常见为感染,无严重不良事件发生。结论:托珠单抗与依那西普治疗pJIA疗效确切,托珠单抗能更快降低炎症指标,改善疾病活动度,并可调节亢进的体液免疫及调节CD4+T、CD19+B细胞。 相似文献
158.
159.
以鲜猪骨、鲜兔骨为原料,采用胰蛋白酶、木瓜蛋白酶和Alcalase碱性蛋白酶分别进行酶解制备猪、兔骨胶原蛋白肽。以小鼠脾淋巴细胞的增殖率为指标,通过单因素实验及正交实验得到最佳的酶解条件。结果表明:酶解猪骨的最佳酶为Alcalase碱性蛋白酶,酶解条件为时间4 h、pH 9.5、酶与底物比6 000 U/g、温度45℃、底物蛋白质量分数6%,其酶解液的脾细胞增殖率为83.41%;酶解兔骨的最佳酶为木瓜蛋白酶,酶解条件为4 h、pH 5.5、酶与底物比7 000 U/g、温度65℃、底物蛋白质量分数6%,其酶解液的脾细胞增殖率为80.70%。 相似文献
160.
刘力恒;万彦军;张佳琪;李平平 《电波科学学报》2025,60(7):2060-2071
矽肺是由吸入结晶二氧化硅粉尘引发的肺部进行性疾病,主要特征为慢性肺部炎症和纤维化,并伴有矽肺结节。流行病学数据显示,该病高发于采矿、建筑施工等职业暴露人群中,已成为全球重大职业卫生问题。其病理进程涉及肺泡巨噬细胞、上皮细胞及成纤维细胞等多类细胞的复杂交互作用,其中适应性免疫系统特别是T淋巴细胞的调控失衡近年来备受关注,并且机制还不十分清楚。本文总结了CD4+辅助性T细胞和CD8+细胞毒性T细胞在矽肺过程中的作用,包括不同类型T细胞间(Th1/Th2/Th17/Treg亚群)的失衡,相同类型的T细胞所分泌细胞因子及其不同细胞功能间的平衡失调都会加速矽肺发展,这种动态失衡在不同病理阶段呈现不同的特异性,并且过度的免疫紊乱会导致呼吸困难和自身免疫性疾病等多种并发症。因此,维持肺部T细胞免疫平衡对于矽肺防治至关重要。与此同时,现阶段临床干预仍局限于粉尘暴露控制、糖皮质激素对症治疗及终末期肺移植,缺乏针对致病机制的特异性疗法。基于T细胞亚群再平衡的新型治疗策略也显示出潜在价值,可能为矽肺提供了新的治疗思路。总的来说,本文系统综述T细胞在矽肺中的双重调控机制,并探讨通过免疫稳态重建实现疾病控制的治疗前景。 相似文献