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Psidium guajava L., commonly known as guava is an important tropical food plant with diverse medicinal values. In traditional medicine, it is used in the treatment of various diseases such as diarrhoea, diabetes, rheumatism, ulcers, malaria, cough, and bacterial infections. The aim of this review is to provide up-to-date information on the ethnomedicinal uses, bioactive compounds, and pharmacological activities of P. guajava with greater emphasis on its therapeutic potentials. The bioactive constituents extracted from P. guajava include phytochemicals (gallic acid, casuariin, catechin, chlorogenic acid, rutin, vanillic acid, quercetin, syringic acid, kaempferol, apigenin, cinnamic acid, luteolin, quercetin-3-O-α-L-arabinopyranoside, morin, ellagic acid, guaijaverin, pedunculoside, asiastic acid, ursolic acid, oleanolic acid, methyl gallate and epicatechin) and essential oils (limonene, trans-caryophyllene, α-humulene, γ-muurolene, selinene, caryophyllene oxide, bisabolol, isocaryophyllene, δ-cadinene, α-copaene, α-cedrene, β-eudesmol, α-pinene, β-pinene, β-myrcene, linalool, α-terpineol and eucalyptol). In vitro and in vivo studies demonstrated that P. guajava possesses pharmacological activities such as antidiabetic, antidiarrhoeal, hepatoprotective, anticancer, antioxidant, anti-inflammatory, antiestrogenic, and antibacterial activities which support its traditional uses. The exhibited pharmacological activities reported may be attributed to the numerous bioactive compounds present in different parts of P. guajava. Based on the beneficial effects of P. guajava as well as its bioactive constituents, it can be exploited in the development of pharmaceutical products and functional foods. However, there is a need for comprehensive studies in clinical trials to establish the safe doses and efficacy of P. guajava for the treatment of several diseases.  相似文献   
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ObjectiveTo explore the disturbed molecular functions and pathways in clear cell renal cell carcinoma (ccRCC) using Gibbs sampling.MethodsGene expression data of ccRCC samples and adjacent non-tumor renal tissues were recruited from public available database. Then, molecular functions of expression changed genes in ccRCC were classed to Gene Ontology (GO) project, and these molecular functions were converted into Markov chains. Markov chain Monte Carlo (MCMC) algorithm was implemented to perform posterior inference and identify probability distributions of molecular functions in Gibbs sampling. Differentially expressed molecular functions were selected under posterior value more than 0.95, and genes with the appeared times in differentially expressed molecular functions ≥5 were defined as pivotal genes. Functional analysis was employed to explore the pathways of pivotal genes and their strongly co-regulated genes.ResultsIn this work, we obtained 396 molecular functions, and 13 of them were differentially expressed. Oxidoreductase activity showed the highest posterior value. Gene composition analysis identified 79 pivotal genes, and survival analysis indicated that these pivotal genes could be used as a strong independent predictor of poor prognosis in patients with ccRCC. Pathway analysis identified one pivotal pathway − oxidative phosphorylation.ConclusionsWe identified the differentially expressed molecular functions and pivotal pathway in ccRCC using Gibbs sampling. The results could be considered as potential signatures for early detection and therapy of ccRCC.  相似文献   
134.
Early and accurate detection of hepatocellular carcinoma (HCC) is essential to improve the prognosis of patients and reduce the morbidity of surgical therapy. Glypican‐3 (GPC3) is a protein abnormally expressed in HCC that has been identified as a serological and histochemical HCC marker. A novel peptide that specifically recognizes GPC3 will facilitate early detection of HCC and guide the treatment strategy. Herein, phage display screening technology is utilized to obtain a GPC3 binding peptide (GBP) using HCC cells expressing GPC3 in varying abundances. After seven rounds of panning, a peptide with sequence of THVSPNQGGLPS is identified with 735.2 ± 53.6 × 10−9 m affinity to GPC3. The ability to target GPC3 in vivo is evaluated by intravenous injection of GBP labeled with a near‐infrared dye, Cy5.5, into a HCC tumor‐bearing mouse model. Significant high tumor accumulation (tumor/muscle ratio: 6.49 ± 0.55) of Cy5.5‐GBP in HepG2 tumors is observed compared with that of the low GPC3 expressing prostate cancer cell line, PC3 (tumor/muscle ratio: 1.15 ± 0.32). By targeting GPC3, GBP differentiates tumor tissues from normal liver tissues in patients, suggesting a great clinical translation potency of GBP. Collectively, GBP demonstrates great potential for HCC detection via fluorescent imaging or histological staining.

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135.
The authors examine properties of daunorubicin (DNR)‐loaded oil‐core multilayer nanocapsules prepared via layer‐by‐layer approach with different polyelectrolyte (PE) coatings such as a standard one (containing polysodium 4‐styrenesulphonate/poly(diallyldimethyl‐ammonium) chloride) and a polysaccharide‐based shell (dextran/chitosan), in regard to the outer layer of poly‐l ‐glutamic acid (PGA) grafted with polyethylene glycol (PGA‐g‐PEG). The nanocarriers are obtained on a cationic nanoemulsion template (stabilized by dicephalic‐type surfactant, N ,N‐bis[3,30‐(trimethylammonio)propyl]‐dodecanamide dimethylsulfate) and layered with the PE shell of different thicknesses resulting in average size of 150 nm in diameter (as shown by dynamic light scattering, scanning electron microscopy and cryogenic‐transmission electron microscopy, and atomic force microscopy). The nanocapsules demonstrate efficient DNR encapsulation and its sustained release under physiological conditions or in the attendance of human serum albumin. The biocompatibility studies using colon carcinoma MC38 and macrophage P388D1 cell lines as well as human erythrocytes reveal that surface charge and outer PE layer type determine nanocarrier features that control their biological activity: protein adsorption, cellular internalization and localization, induction of apoptosis, and hemolytic activity. The investigations indicate that polysaccharide‐coated nanocapsules present a considerable potential for application as efficient DNR delivery systems in chemotherapy of colon cancer as an alternative to nanocarriers with PEG‐ylated shell.

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136.
Apoptin is a chicken anemia virus-derived,p53-independent,bcl-2-insensitive apoptotic protein with the ability to specifically induce apoptosis of various human tumor cells,but not of normal diploid cells.To explore the application of apoptin in tumor gene therapy,we used a recombinant fowlpox virus expressing apoptin protein (vFV-Apoptin) to investigate the anti-tumor effectes of vFV-Apoptin on human cervical carcinoma(HeLa) cells in vivo and in vitro through 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetraz...  相似文献   
137.
基于Hill动力学结合Michaelis-Menten方程,本文建立理论模型研究内质网定位的蛋白Nogo-B与冠状动脉疾病相关连接蛋白JCAD诱导肝癌(HCC)基因激活.理论模型考虑:(1) Nogo-B诱导oxidized low density lipoprotein (oxLDL)蛋白降解,降解的oxLDL(DoxLDL)通过促进Lysopho-sphatidic acid (LPA)合成而激活HCC基因表达;(2) JCAD与large tumor suppressor homolog 2 (LATS2)激酶相互作用调节Yes-associated protein (YAP)蛋白磷酸化,进而激活Hippo信号通路中与肿瘤形成相关的增殖因子,导致HCC的发生发展.研究发现,oxLDL在很短的时间内降解,DoxLDL会很快激活下游级联通路信号(Lysophosphatidylcholine (LPC)、autotaxin(ATX)、LPA等),在很大程度上提升了Hippo信号通路中YAP的活性,进而激活下游癌基因(connective tissue growth factor (C...  相似文献   
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139.
杜卫东  何超  王达  马建军 《应用数学》2013,35(7):519-522
目的研究受体型酪氨酸激酶变异体RON△160表达对结肠癌细胞迁移、浸润能力的影响.方法将携有受体型酪氨酸激酶RON变异体RON△160 cDNA的质粒转染入结肠癌细胞株RKO细胞,挑选稳定转染克隆,以过河实验和Transwel 趋化运动实验检测细胞迁移能力;Matrigel基质浸润实验检测细胞浸润能力,Western blot检测E-钙粘连蛋白(E-cadherin)表达的变化.结果转染RON△160后RKO细胞的过河时间为(38.00±1.63)h,明显短于未转染组与载体对照组的(69.50±2.52)h与(72.00±1.63)h,差异均有统计学意义(均P<0.05).转染后RKO细胞的穿膜能力显著增强,穿膜细胞数为(59.22±6.67)个/HP、未转染组为(25.90±4.56)个/HP、载体对照组为(28.33±6.75)个/HP,差异均有统计学意义(均P<0.05).转染RON△160后,RKO细胞中E-cadherin表达降低(P<0.05).结论 RON△160转染可以降低E-cadherin表达,降低肿瘤细胞间的黏附性,增加结肠癌细胞RKO的移动、浸润能力.RON△160的表达可能是结肠癌浸润、转移的机制之一.  相似文献   
140.
戴璇璇  周毅力  刘超  闫东升  王瓯晨 《应用数学》2013,35(20):1802-1806
目的:探讨甲状腺乳头状癌(PTC)中特征性的miRNA表达谱以及临床病理意义。方法对52例PTC及7例良性甲状腺肿瘤手术切除标本采用基因芯片技术及RNA印迹杂交法检测miRNA的表达,对过表达的miRNA表达水平与PTC临床病理特征之间的关系进行分析。结果(1)用基因芯片技术筛检发现 PTC 组织中5例过表达的 miRNAs(miR-375、miR-34a、miR-146b、miR-222、miR-31)。(2)RNA印迹杂交法验证芯片结果及检测其他miRNAs结果显示:miR-34a、miR-146b、miR-31、miR-21和miR-221在PTC组织中的表达水平较癌旁正常甲状腺组织显著升高(P<0.05)。MiR-146b和miR-221在PTC组织中的过表达率较良性甲状腺肿瘤组织显著升高(P<0.01)。PTC患者中包膜侵犯组、淋巴结转移组、TNM分期III- IV期组及AGES系统评分≥5分组miR-221的表达水平均明显高于相应对照组(P<0.05或0.01);而男性PTC患者的miR-146b表达水平明显高于女性PTC患者(P<0.05)。结论 miR-146b、miR-221、miR-21和miR-31的过表达与PTC的发生、发展有关;过表达的miR-221和miR-146b与PTC的预后不良有关。  相似文献   
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