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11.
Emerging evidence has indicated that long noncoding RNA (lncRNAs) play crucial roles in regulating thyroid cancer (TC) development. Linc00210 is a newly identified lncRNA which plays an oncogenic role in hepatocellular carcinoma and nasopharyngeal carcinoma, but whether Linc00210 can modulate the development of TC remains elusive. Here, we found that Linc00210 expression was upregulated in TC tissues compared to the matched noncancerous tissues. Overexpression of Linc00210 augmented the proliferation, migration, and invasion of TC cells. Mechanistically, Linc00210 served as a sponge for miR-195-5p, thereby counteracting its ability in downregulating the expression of IGF1R and the activation of PI3K/Akt signaling. Moreover, inhibition of Linc00210 suppressed the growth of TC cells in nude mice. Our findings for the first time uncovered the oncogenic property of Linc00210 in TC.  相似文献   
12.
The aim of this study was to investigate the pathogenesis of Mycoplasma pneumoniae (MP) infection and its association with cardiac and hepatic damage. Between March 2013 and March 2014, 59 children with MP pneumonia (MPP) and 30 healthy children were enrolled. Serum titers of TLR4, T cell immunoglobulin and mucin‐domain (TIM) 3, IL‐10, TNF‐α, and IFN‐γ were measured both in children with MPP and healthy children. Additionally, MP‐specific antibody titer and creatine kinase‐MB (CK‐MB), and alanine transaminase (ALT) titers were measured in patients with MPP. There were significant differences between the MPP patients and healthy controls in titers of TIM1 (P < 0.01), TLR2 (P = 0.028), TLR4 (P = 0.019), IL‐10 (P < 0.01), TNF‐α (P < 0.01) and IFN‐γ (P < 0.01); however, no significant difference was found in TIM3 titers (P = 0.8181). TIM1 was correlated with CK‐MB (P = 0.025), whereas both TIM1 and TLR2 titers were correlated with MP‐specific antibody titers (P < 0.001; P = 0.003, respectively). Additionally, there were correlations between ALT, TIM3, and TLR2 titers (P = 0.025; P = 0.037, respectively). The titers of TIM1 were significantly higher in patients with cardiac damage (P = 0.007) than in those without it, whereas the titers of TLR2 were significantly higher in patients with hepatic damage (P = 0.026) than in those without it. TLR2, TLR4 and TIM1 may be involved in the process of MP infection. Additionally, TLR2, TLR4, TIM1 and TIM3 may play particular roles in the pathogenesis of MPP‐associated cardiac and hepatic damage.  相似文献   
13.
基于InVEST模型的疏勒河上游产水量时空变化特征分析   总被引:1,自引:0,他引:1  
开展山区流域产水量的定量评估研究,有利于区域水资源保护规划的制定、生态补偿机制的建立以及生态平衡的维系。然而,目前对我国西部高寒山区产水量的时空变化评估及其影响因素的研究依然较为缺乏。选取青藏高原东北缘祁连山西段疏勒河上游为研究区,基于InVEST(Integrate Valuation of Ecosystem Services and Tradeoffs Tools)模型定量估算并分析了2001-2019年产水量的时空变化特征及影响因素。结果表明:(1)2001-2019年,研究区年均气温和年实际蒸散量呈增加趋势(P>0.05),年降水量和NDVI则显著增加(P<0.05);(2)年均总产水量为13.66×108 m3,空间分布呈现山地高海拔区较高,河谷低海拔区较低的特征;(3)19年来产水量以0.26×108 m3/a的速率显著增加(P<0.01)。其中,高海拔区的产水量显著增加,约占整个研究区的32.01%;然而,仅有8.39%的低海拔区产水量显著下降(P<0.05)且集中分布在西北部;(4)产水量与降水量显著正相关,同气温、实际蒸散量、归一化植被指数(NDVI, Normalized Difference Vegetation Index)和根系深度显著负相关(P<0.001);(5)产水功能一般重要级别区占研究区面积的47.26%,极重要和高度重要级别区占总面积的28.25%。研究为祁连山国家公园水资源的动态评估、有效管理和可持续发展提供了科学参考。  相似文献   
14.
Purpose: The purpose of this study was to determine whether α-galactosylceramide (α-GalCer), a synthetic glycolipid agonist of natural killer T (NKT) cells, can ameliorate exercise-induced immune imbalance. Methods: Eight-week-old female Sprague-Dawley rats were trained with a progressively increasing load for 9 weeks. At 36 h and at 7 d after training, groups of rats were euthanized. The whole blood was used to detect hemoglobin(Hb), plasma was analyzed for hormones testosterone(T) and corticosterone(C), and spleen was harvested for detecting NKT cells and interferon-γ (IFN-γ) and interleukin (IL)-4 producing cells. Results: Two-way analysis of variance (ANOVA) showed significant differences between training and time in Series 1. The results showed, at 36h after training, that the decrease in Hb, T and C concentration reflected overtraining or excessive exercise. At 7 d after training, NKT cell populations decreased, and a T helper 1/T helper 2 (Th1/Th2) lymphocyte imbalance occurred. In Series 2, α-galactosylceramide (α-GalCer), an NKT cell activator was found to enhance NKT cell numbers by 69% and shift the Th1/Th2 lymphocyte imbalance by observably decreasing the frequency of IL-4 secreting cells. Conclusion: These data showed that, in addition to Th1/Th2 self-regulation, α-GalCer played an important modulatory role in the exercise-induced Th1/Th2 lymphocyte imbalance, which may be correlative with NKT immunoregulatory cells.  相似文献   
15.
Liu  Yanqi  Li  Xinjuan  Wu  Hanchun  Zeng  Zhuo  Zhang  Duan  Wang  Peijie  Zhang  Lisheng  Fang  Yan 《Plasmonics (Norwell, Mass.)》2017,12(6):1861-1867
Plasmonics - Tip-enhanced Raman spectroscopy (TERS) has received much attention due to excellent spatial resolution and high detection sensitivity. However, its performance depends crucially on the...  相似文献   
16.
Guozhen Wu  Peijie Wang 《Chirality》2014,26(5):255-259
The bond polarizability and differential bond polarizability are introduced to interpret the Raman and Raman optical activity (ROA) intensities, calculated by the ab initio method. Chiral S 2‐amino 1‐propanol is taken as a model molecule. Through these bond polarizabilities, we observe that symmetric and antisymmetric coordinates are, respectively, more significant in Raman and ROA. It is noted that in S 2‐amino 1‐propanol those bonds lying on a common plane share the same differential bond polarizability sign while that of the asymmetric C‐H bond which protrudes out of the plane possesses the opposite sign. We conclude that ROA can offer more stereostructural implications than Raman and that the differential bond polarizability is potentially the appropriate parameter in interpreting the 3D configuration of a molecule. Chirality 26:255–259, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
17.
Peijie C  Hongwu L  Fengpeng X  Jie R  Jie Z 《Life sciences》2003,72(20):2255-2262
To determine whether immunity and neuroendocrine system is altered by different loads of exercise training in rats, eight-week-old male Sprague-Dawley rats were randomly assigned to one of the three groups: 1) cage control group (CCG); 2) moderate load training (MLT) (swimming at the intensity of 1.4 m/sec water flowing for 60 min per day); 3) heavy load training (HLT) (swimming at the intensity of 1.8 m/sec water flowing for 120 min per day). MLT and HLT rats were assigned to swim for 6 days per week for total of 6 weeks. All rats were sacrificed 36 h after their last training session. Splenocytes were pooled for assay of cell proliferation and neuropeptide contents in the hypothalamus, hypophysis and plasma were determined by radioimmunoassay while glucocorticoid specific binding in intact thymus was measured by radioligand binding assay. All rats were weighed weekly. The results showed that after 6-week training, rat splenocyte proliferation in response to Con A and LPS decreased in HLT rats compared with MLT and CCG rats. In addition, the contents of beta-endorphin, dynorphin A, arginine vasopressin and oxytocin in the hypothalamus, hypophysis and plasma were altered by HLT, as shown by increased plasma concentration of glucocorticoids and decreased glucocorticoids specific binding in intact thymus compared with MLT and CCG. Furthermore, a decreased body mass in HLT rats has been observed. The body mass of HLT rats was significantly lower than that in CCG and MLT rats at the end of the swimming training period. These data suggest that 6-week heavy load training induces the dysfunction of immunity and neuroendocrine responses, which might be one of the underlying mechanisms of immune dysfunction in overtraining.  相似文献   
18.
The conditions under which the localized surface plasmon resonance (LSPR) model can be applied to the calculation of surface-enhanced Raman scattering (SERS) enhancement factors have been questioned because the chemical effect presents simultaneously with LSPR effect, resulting in calculations that are not always consistent with the measured data. The SERS spectra of crystal violet (CV) molecules on single, dimer, trimer, and aggregates of silver microparticles surface-modified with nanostructures (MSMN) were obtained. It is found that the chemical effect is determined by the chemical adsorption behavior of CV molecules on single particle. As more particles are introduced as amplifiers, to assemble dimer, trimer, and aggregates, no new SERS signals related to the chemical effect can be observed, except for the further enhancement to the original signals. The further enhancement is attributed to the LSPR effect from the electromagnetic coupling with introduced particles. This is also demonstrated by dark field scattering. The LSPR theoretical values of single, dimer, trimer, and aggregates of MSMNs should fit the measured enhancement factor (G LSPR) after correcting the SERS enhancement factor (G SERS) with the chemical enhancement factor on the single particle (G Chem-Sgl), i.e., G LSPR?=?G SERS/G Chem-Sgl. Tip-enhanced Raman spectroscopy with a gold nanoparticle further implies that this could be extended to nanoparticle systems. This work provides an effective and simple route, whereby only the chemical effect from a single particle needs to be considered when studying the fit between the LSPR model and the measured LSPR enhancement factor.  相似文献   
19.
疏勒河源高寒草甸土壤微生物生物量碳氮变化特征   总被引:3,自引:2,他引:3  
刘放  吴明辉  魏培洁  贾映兰  陈生云 《生态学报》2020,40(18):6416-6426
土壤微生物生物量是土壤有机质的活性部分,是反映土壤质量和碳氮循环机制的重要指标。本文以青藏高原东北缘疏勒河源高寒草甸为研究对象,对土壤微生物生物量碳(SMBC, mg/kg)和微生物生物量氮(SMBN, mg/kg)的不同季节(春、夏、秋、冬)和土层(0—10、10—20、20—30、30—40、40—50 cm)变化特征及其影响因素进行研究。结果表明:(1)不同土层SMBC均表现为春季开始逐渐升高、夏季达到最大值、秋季逐渐降低、冬季值最小,而SMBN春季开始逐渐降低、夏季值最小、秋季逐渐升高、冬季达到最大值。(2)SMBC、SMBN随着土壤深度的增加而下降,0—10 cm层SMBC、SMBN显著高于40—50 cm层,且SMBC、SMBN0—10 cm层的季节变幅显著大于40—50 cm层。(3)0—50 cm土层SMBC/SMBN表现为春季开始逐渐升高、夏季达到最大值、秋季逐渐降低、冬季值最小,其季节变化范围为8.77—23.59,处于较高水平。(4)SMBC、SMBN、SMBC/SMBN的季节和土层变化主要受植被地下生物量和土壤温度的影响。(5)各土层SMBC/SOC均表现为春季开始逐渐升高、夏季达到最大值、秋季逐渐降低、冬季值最小,而SMBN/TN春季开始逐渐降低、夏季值最小、秋季逐渐升高、冬季达到最大值。除夏季土层间无显著差异外,SMBC/SOC与SMBN/TN均表现为0—10 cm层显著高于40—50 cm层。(6)0—50 cm土层SMBC/SOC夏秋季显著高于冬春季且其季节变化范围为0.58%—1.18%,而SMBN/TN秋冬季显著高于夏季且其季节变化范围为0.39%—0.72%。综上,季节变化和剖面深度均对SMBC、SMBN产生显著影响且0—10 cm土层对SMBC、SMBN的累积能力最强。  相似文献   
20.
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