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71.
The biological functions of the tumor suppressor ING1 have been studied extensively in the past few years since it was cloned. It shares many biological functions with p53 and has been reported to mediate growth arrest, senescence, apoptosis, anchorage-dependent growth, chemosensitivity, and DNA repair. Some of these functions, such as cell cycle arrest and apoptosis, have been shown to be dependent on the activity of both ING1 and p53 proteins. Two recent reports by Scott and colleagues demonstrate that p33ING1 (one of the ING1 isoforms) translocates to the nucleus and binds to PCNA upon UV irradiation. Here we report that p33ING1 mediates UV-induced cell death in melanoma cells. We found that overexpression of p33ING1 increased while the introduction of an antisense p33ING1 plasmid reduced the apoptosis rate in melanoma cells after UVB irradiation. We also demonstrated that enhancement of UV-induced apoptosis by p33ING1 required the presence of p53. Moreover, we found that p33ING1 enhanced the expression of endogenous Bax and altered the mitochondrial membrane potential. Taken together, these observations strongly suggest that p33ING1 cooperates with p53 in UVB-induced apoptosis via the mitochondrial cell death pathway in melanoma cells. 相似文献
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目的:探讨布地奈德福莫特罗吸入治疗对慢性支气管哮喘患者的临床疗效及其对患者血清炎性因子水平、肺功能和生活质量的影响。方法:选择2014年2月至2016年2月于我院呼吸内科就诊并确诊为慢性支气管哮喘患者123例,根据随机数字表法分为观察组65例和对照组58例。比较两组患者治疗前后血清白介素17(IL-17)、白介素33(IL-33)、基质金属蛋白酶9(MMP-9)、肺功能、生活质量评分的变化、临床疗效有效率及不良反应的发生情况。结果:观察组的总有效率为92.3%(60/65),显著高于对照组(81.03%,P0.05)。治疗后,两组患者的血清IL-17、IL-33水平与治疗前相比均显著降低(P0.05),且观察组显著低于对照组(P0.05);两组血清MMP-9水平与治疗前相比差异均无统计学意义(P0.05);观察组患者的第一秒用力呼吸容积(FEV1)、峰值呼气流速(PEF)与第一秒用力呼气容积与用力肺活量比值(FEV1/FVC)水平均明显增加,且观察组上述指标明显高于对照组(P0.05);圣.乔治呼吸问卷(SGRQ)评分结果显示观察组患者的生活质量显著高于对照组患者。结论:布地奈德福莫特罗吸入治疗对慢性支气管哮喘临床效果显著,可显著控制炎症反应,改善肺功能,显著提升患者生活质量。 相似文献
74.
Roles of ST2, IL‐33 and BNP in predicting major adverse cardiovascular events in acute myocardial infarction after percutaneous coronary intervention 下载免费PDF全文
Xiao‐Long Wang Jun‐Yi Liu Fang‐Yun Jiang Xiao‐Li Huang Jing‐Yu Hang Wei Qin Shi‐Xin Ma Jie Zhang Min‐Jie Yuan Jing‐Bo Li Zhi‐Gang Lu Meng Wei 《Journal of cellular and molecular medicine》2017,21(11):2677-2684
This study investigated roles of serum ST2, IL‐33 and BNP in predicting major adverse cardiovascular events (MACEs) in acute myocardial infarction (AMI) after percutaneous coronary intervention (PCI). Blood samples were collected from the included AMI patients (n = 180) who underwent PCI. All patients were divided into the MACEs and MACEs‐free groups. Enzyme‐linked immunosorbent assay was performed to measure serum levels of ST2, IL‐33 and BNP. Severity of coronary artery lesion was evaluated by Gensini score. Pearson correlation analysis was used. A receiver operating characteristics curve was drawn to evaluate the potential roles of ST2, IL‐33 and BNP in predicting MACEs, and Kaplan–Meier curve to analyse the 1‐year overall survival rate. Logistic regression analysis was conducted to analyse the independent risk factors for MACEs. Compared with the MACEs‐free group, the serum levels of ST2, IL‐33 and BNP were significantly higher in the MACEs group. Serum levels of ST2, IL‐33 and BNP were positively correlated with each other and positively correlated with Gensini score. The area under curves of ST2, IL‐33 and BNP, respectively, were 0.872, 0.675 and 0.902. The relative sensitivity and specificity were, respectively, 76.27% and 85.92%, 69.49% and 58.68%, as well as, 96.61% and 77.69%. Serum levels of ST2, IL‐33 and BNP were independent risk factors for MACEs. The 1‐year overall survival rate was higher in AMI patients with lower serum levels of ST2, IL‐33 and BNP. In conclusion, serum levels of ST2, IL‐33 and BNP have potential value in predicting MACEs in AMI patients undergoing PCI. 相似文献
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Placement of a cell into an external electric field causes a local charge redistribution inside and outside of the cell in the vicinity of the cell membrane, resulting in a voltage across the membrane. This voltage, termed the induced membrane voltage (also induced transmembrane voltage, or induced transmembrane potential difference) and denoted by ΔΦ, exists only as long as the external field is present. If the resting voltage is present on the membrane, the induced voltage superimposes (adds) onto it. By using one of the potentiometric fluorescent dyes, such as di-8-ANEPPS, it is possible to observe the variations of ΔΦ on the cell membrane and to measure its value noninvasively. di-8-ANEPPS becomes strongly fluorescent when bound to the lipid bilayer of the cell membrane, with the change of the fluorescence intensity proportional to the change of ΔΦ. This video shows the protocol for measuring ΔΦ using di-8-ANEPPS and also demonstrates the influence of cell shape on the amplitude and spatial distribution of ΔΦ. 相似文献
77.
Melissa Paulite Zahra Fakhraai Boris B. Akhremitchev Kerstin Mueller Gilbert C. Walker 《Journal of visualized experiments : JoVE》2009,(33)
This paper aims to instruct the reader in the assembly and operation of an infrared near-field microscope for imaging beyond the diffraction limit. The apertureless near-field microscope is a light scattering-type instrument that provides infrared spectra at circa 20 nm resolution. A complete list of components and a step-by-step protocol for use is provided. Common errors in assembly and instrument tuning are discussed. A representative data set that shows the secondary structure of an amyloid fibril is presented. 相似文献
78.
Xiaojin Liu Yan Wu Yanchun Zhou Liangming Zeng Tian Huang 《Biochemical and biophysical research communications》2009,386(1):181-185
Interleukin (IL)-33 is a recently described member of the IL-1 family and has been shown to induce production of T helper type 2 cytokines. In this study, an anti-IL-33 antibody was evaluated against pulmonary inflammation in mice sensitized and challenged with ovalbumin. The anti-IL-33 or a control antibody (150 μg/mouse) was given intraperitoneally as five doses before the sensitization and antigen challenge. Treatment with anti-IL-33 significantly reduced serum IgE secretion, the numbers of eosinophils and lymphocytes, and concentrations of IL-4, IL-5, and IL-13 in bronchoalveolar lavage fluid compared with administration of a control antibody. Histological examination of lung tissue demonstrated that anti-IL-33 significantly inhibited allergen-induced lung eosinophilic inflammation and mucus hypersecretion. Our data demonstrate for the first time that anti-IL-33 antibody can prevent the development of asthma in a mouse model and indicate that blockade of IL-33 may be a new therapeutic strategy for allergic asthma. 相似文献
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We have studied the naturally split α subunit of the DNA polymerase III (DnaE) intein from Nostoc punctiforme PCC73102 (Npu) using purified proteins and determined an apparent first-order rate constant of (1.1±0.2)×10-2 s−1 at 37 °C. This represents the highest rate reported for the protein trans-splicing reaction so far (t1/2 of ∼ 60 s). Furthermore, the reaction was very robust and high-yielding with respect to different extein sequences, temperatures from 6 to 37 °C, and the presence of up to 6 M urea. Given these outstanding properties, the Npu DnaE intein appears to be the intein of choice for many applications in protein and cellular chemistry. 相似文献