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1.
目的:探究喜树碱-氟尿苷(CPT-FUDR)纳米颗粒对口腔鳞癌Tca-8113细胞增殖与迁移的影响。方法:制备喜树碱-氟尿苷纳米颗粒,通过丁达尔现象证明已组装完毕。将制备好的纳米颗粒组和喜树碱(CPT)单药组、氟尿苷(FUDR)单药组以及两种单药混合组(CPT/FUDR)作对比,采用MTT实验检测药物对口腔鳞癌细胞Tca-8113增殖的抑制作用,通过划痕实验探究CPT-FUDR纳米颗粒和CPT/FUDR混合药物对细胞迁移能力的影响。结果:MTT结果显示:在药物浓度大于0.1μM时,随着浓度的增加,四组细胞存活率均明显下降(P0.05),而CPT-FUDR纳米颗粒组Tca-8113细胞的存活率明显低于单药CPT、FUDR和CPT/FUDR混合物组(P0.05)。在划痕实验中,培养48 h后,CPT/FUDR混合物组和CPT-FUDR纳米颗粒组均显著低于空白组(P0.05),且CPT-FUDR纳米颗粒组显著低于CPT/FUDR混合物组(P0.05)。结论:在体外,CPT-FUDR纳米颗粒对口腔鳞癌Tca-8113细胞的增殖与迁移有较好的抑制作用,且抑制效果优于CPT/FUDR两种单药混合。  相似文献   
2.
Hoverman JT  Relyea RA 《Oecologia》2007,154(3):551-560
Studies of inducible defenses have traditionally examined prey responses to one predator at a time. However, prey in nature encounter combinations of predators that should force them to produce phenotypic compromises. We examined how snails (Helisoma trivolvis) alter their phenotype in the presence of three different predator species that were presented alone and in pairwise combinations. When snails were exposed to each predator alone, they formed predator-specific defenses that reflected the differences in each predator’s foraging mode. When snails were exposed to pairwise combinations of predators, their phenotype was dependent on their ability to detect each predator, the risk posed by each predator, and the effectiveness of a given defense against each predator. Consequently, responses to combined predators were typically biased towards one of the predators in the pair. This suggests that prey facing combined predators do not form simple intermediate defenses and, as a result, may experience enhanced mortality risk when they encounter natural predator regimes.  相似文献   
3.
现常用于检测高血压病的彩色、脉冲多普勒及二维、M型超声心动图几种方法,各有其优点与不足。本文利用其各自的优点,运用上述复合超声心动图法检测96例高血压病患者及86例正常人,进行了分析研究。认为,此法检诊高血压病是实用、可行的。  相似文献   
4.
复合污染研究的新进展   总被引:59,自引:4,他引:59  
对多种污染物相互作用形成的复合污染效应的研究已成为环境科学发展的重要方向之一。本文从元机复合污染、无机-有机复合污染以及有机复合污染3个方面对复合污染效应的最新进展进行了综述,并从化学、生理学、酶学、细胞学等角度出发探计了复合污染机理,指出了复合污染研究中存在的若干问题和发展方向。  相似文献   
5.
Objective: The research is to explore the diagnostic value of several detection methods including separated and combined detection of the related genes and related proteins of breast cancer and combined detection of all genetic markers and serum protein markers on breast cancer. Method: The mRNA level expression of the related genes of breast cancer was detected by FQ-PCR technique and the ratio of BRCA-1, Myc, C-erbB2 and β2 micro-globulin was used to express levels of BRCA-1, Myc and C-erbB2; the related proteins of breast cancer were detected through ELISA. Then the research data was analyzed by SPSS19.0 software with t-test as comparison method, and ROC curve was used to calculate the sensitivity, specificity and accuracy of the diagnostic models. Result: No difference can be found among the six indexes in the control group and benign breast tumor group while compared with the benign breast tumor group and the control group, the breast cancer group was significantly different from them; combined detection of genes and that of proteins were both superior to their separated detection; all-marker combined detection was superior to separated detection, which is consistent with combined detection of genes and proteins. Conclusion: More detection indexes will not necessarily outcome better detection effect. Hence, appropriate detection indexes and number are needed to achieve better diagnosis effect. In order to conduct more specific method, more test samples are needed for further researches.  相似文献   
6.
We present here a general system for the coordination attachment of therapeutic proteins to a drug delivery system and its application in combined therapy. Proof of concept is demonstrated by the synthesis and testing of the targeted drug delivery system for cytostatics, which is based on a combination of the drug carrier Zn-porphyrin-cyclodextrin conjugates and their supramolecular coordination complexes with immunoglobulins. This system can be as readily used for a variety of therapeutic and targeting proteins including PAs, MAs, lectins, and HSA. Moreover, it allows combined photodynamic therapy, cell targeted chemotherapy and immunotherapy. When tested in a mouse model with human C32 carcinoma, the therapeutic superiority of the coordination assembly nanosystem was shown in comparison with the efficacy of building blocks used for the construction of the system.  相似文献   
7.
目的:研究药剂科积极参与下中西药联合使用对消化内科患者用药合理性的影响。方法:选取我院2014年1月至2015年12月收治且确诊为消化性疾病患者184例,通过随机数表法将患者平均分为对照组和实验组,对照组给予临床常规中西药联合治疗,观察并统计临床反应;实验组给予中西药联合治疗,由本院药剂科参与人员、临床医师联合管理。统计并分析两组疗效、用药合理性及不良反应。结果:对照组总有效率为82.60%,明显低于实验组的94.56%(X~2=5.944,p=0.015);对照组用药合理率为77.17%,明显低于实验组的89.13%(X~2=5.102,p=0.024);对照组不良反应合理率为61.96%,明显低于实验组的88.04%(X~2=18.026,p0.001)。结论:药剂科的积极参与提高了中西药联合使用对消化内科患者的疗效,也降低了不良反应的发生率。  相似文献   
8.
9.
目的:探讨联合检测血清胸苷激酶1(TK1)与乳酸脱氢酶(LDH)水平在非霍奇金淋巴瘤(NHL)患者鉴别诊断及疗效监测中的临床意义。方法:收集2016年1月至2018年6月我院诊治的111例非霍奇金淋巴瘤的初诊患者血清标本,并选择50例正常人血清标本作为对照,采用免疫印迹增强发光法检测TK1浓度,比色法检测LDH浓度。所有患者随访至少1年,分析和比较惰性NHL与侵袭性NHL及各自四类分期之间血清TK1和LDH水平的差异,化疗后完全缓解、部分缓解与未缓解组LDH水平以及NHL患者中血清TK1和LDH的阳性率。结果:高度侵袭性NHL患者和侵袭性NHL患者血清TKI和LDH水平与惰性NHL患者相比显著增高(P0.05),但惰性NHL患者血清TK1和LDH水平与正常组之间差异无统计学意义(P0.05);Ⅲ、Ⅳ期侵袭性NHL患者血清TK1和LDH水平与Ⅰ、Ⅱ期患者相比显著增高(P0.05)。与化疗前相比,四次化疗后,完全缓解组NHL患者血清LDH水平下降21.05%,部分缓解组为16.66%,病情稳定组血清LDH水平升高至11.54%,三组NHL患者血清LDH水平比较差异具有统计学意义(P0.008),两组之间的差异均有统计学意义(P0.05)。结论:联合检测血清TK1和LDH水平对于NHL患者的鉴别诊断、疗效评估均具有重要参考价值。  相似文献   
10.
The use of parallel labeling experiments for 13C metabolic flux analysis (13C-MFA) has emerged in recent years as the new gold standard in fluxomics. The methodology has been termed COMPLETE-MFA, short for complementary parallel labeling experiments technique for metabolic flux analysis. In this contribution, we have tested the limits of COMPLETE-MFA by demonstrating integrated analysis of 14 parallel labeling experiments with Escherichia coli. An effort on such a massive scale has never been attempted before. In addition to several widely used isotopic tracers such as [1,2-13C]glucose and mixtures of [1-13C]glucose and [U-13C]glucose, four novel tracers were applied in this study: [2,3-13C]glucose, [4,5,6-13C]glucose, [2,3,4,5,6-13C]glucose and a mixture of [1-13C]glucose and [4,5,6-13C]glucose. This allowed us for the first time to compare the performance of a large number of isotopic tracers. Overall, there was no single best tracer for the entire E. coli metabolic network model. Tracers that produced well-resolved fluxes in the upper part of metabolism (glycolysis and pentose phosphate pathways) showed poor performance for fluxes in the lower part of metabolism (TCA cycle and anaplerotic reactions), and vice versa. The best tracer for upper metabolism was 80% [1-13C]glucose+20% [U-13C]glucose, while [4,5,6-13C]glucose and [5-13C]glucose both produced optimal flux resolution in the lower part of metabolism. COMPLETE-MFA improved both flux precision and flux observability, i.e. more independent fluxes were resolved with smaller confidence intervals, especially exchange fluxes. Overall, this study demonstrates that COMPLETE-MFA is a powerful approach for improving flux measurements and that this methodology should be considered in future studies that require very high flux resolution.  相似文献   
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