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排序方式: 共有461条查询结果,搜索用时 151 毫秒
141.
Hairin Taha Chung Yeng Looi Aditya Arya Won Fen Wong Lee Fah Yap Mohadeseh Hasanpourghadi Mustafa A. Mohd Ian C Paterson Hapipah Mohd Ali 《PloS one》2015,10(5)
Phytochemicals from Pseuduvaria species have been reported to display a wide range of biological activities. In the present study, a known benzopyran derivative, (6E,10E) isopolycerasoidol (1), and a new benzopyran derivative, (6E,10E) isopolycerasoidol methyl ester (2), were isolated from a methanol extract of Pseuduvaria monticola leaves. The structures of the isolated compounds were elucidated by spectroscopic methods including 1D and 2D NMR, IR, UV, and LCMS-QTOF, and by comparison with previously published data. The anti-proliferative and cytotoxic effects of these compounds on human breast cancer cell-lines (MCF-7 and MDA-MB-231) and a human normal breast epithelial cell line (MCF-10A) were investigated. MTT results revealed both (1) and (2) were efficient in reducing cell viability of breast cancer cells. Flow cytometry analysis demonstrated that (1) and (2) induced cell death via apoptosis, as demonstrated by an increase in phosphotidylserine exposure. Both compounds elevated ROS production, leading to reduced mitochondrial membrane potential and increased plasma membrane permeability in breast cancer cells. These effects occurred concomitantly with a dose-dependent activation of caspase 3/7 and 9, a down-regulation of the anti-apoptotic gene BCL2 and the accumulation of p38 MAPK in the nucleus. Taken together, our data demonstrate that (1) and (2) induce intrinsic mitochondrial-mediated apoptosis in human breast cancer cells, which provides the first pharmacological evidence for their future development as anticancer agents. 相似文献
142.
Baligh R. Yehia Alisa J. Stephens-Shields John A. Fleishman Stephen A. Berry Allison L. Agwu Joshua P. Metlay Richard D. Moore W. Christopher Mathews Ank Nijhawan Richard Rutstein Aditya H. Gaur Kelly A. Gebo HIV Research Network 《PloS one》2015,10(6)
Background
The HIV care continuum (diagnosis, linkage to care, retention in care, receipt of antiretroviral therapy (ART), viral suppression) has been used to identify opportunities for improving the delivery of HIV care. Continuum steps are typically calculated in a conditional manner, with the number of persons completing the prior step serving as the base population for the next step. This approach may underestimate the prevalence of viral suppression by excluding patients who are suppressed but do not meet standard definitions of retention in care. Understanding how retention in care and viral suppression interact and change over time may improve our ability to intervene on these steps in the continuum.Methods
We followed 17,140 patients at 11 U.S. HIV clinics between 2010-2012. For each calendar year, patients were classified into one of five categories: (1) retained/suppressed, (2) retained/not-suppressed, (3) not-retained/suppressed, (4) not-retained/not-suppressed, and (5) lost to follow-up (for calendar years 2011 and 2012 only). Retained individuals were those completing ≥2 HIV medical visits separated by ≥90 days in the year. Persons not retained completed ≥1 HIV medical visit during the year, but did not meet the retention definition. Persons lost to follow-up had no HIV medical visits in the year. HIV viral suppression was defined as HIV-1 RNA ≤200 copies/mL at the last measure in the year. Multinomial logistic regression was used to determine the probability of patients’ transitioning between retention/suppression categories from 2010 to 2011 and 2010 to 2012, adjusting for age, sex, race/ethnicity, HIV risk factor, insurance status, CD4 count, and use of ART.Results
Overall, 65.8% of patients were retained/suppressed, 17.4% retained/not-suppressed, 10.0% not-retained/suppressed, and 6.8% not-retained/not-suppressed in 2010. 59.5% of patients maintained the same status in 2011 (kappa=0.458) and 53.3% maintained the same status in 2012 (kappa=0.437).Conclusions
Not counting patients not-retained/suppressed as virally suppressed, as is commonly done in the HIV care continuum, underestimated the proportion suppressed by 13%. Applying the care continuum in a longitudinal manner will enhance its utility. 相似文献143.
Mohammed A. A. Alqumber Naseem Akhter Shafiul Haque Aditya K. Panda Raju K. Mandal 《PloS one》2014,9(4)
Aim
Allelic polymorphism in codon 72 of the p53 tumor suppressor gene causes imbalance of p53 protein expression. Earlier studies have shown association between allelic polymorphism in codon 72 of the p53 gene with risk of ovary cancer (OC); however the results are inconclusive and conflicting. Therefore, we performed this meta-analysis to investigate the relation between p53 codon 72 Arg>Pro polymorphism and overall OC susceptibility.Methods
We searched all eligible published studies based on the association between codon 72 of the p53 Arg>Pro polymorphism and risk of OC. Data were pooled together from individual studies and meta-analysis was performed. Pooled odds ratios (ORs) and 95% CI were calculated for allele contrast, homozygous, heterozygous, dominant and recessive genetic models.Results
A total of twelve studies comprising of 993 OC cases and 1264 healthy controls were included in this meta-analysis. Overall, no significant association was detected for Pro allele carrier (Pro vs. Arg: p = 0.916; OR = 0.980, 95% CI = 0.677 to 1.419), homozygous (Pro/Pro vs. Arg/Arg: p = 0.419; OR = 0.731, 95% CI = 0.341 to 1.564), heterozygous (Arg/Pro vs. Arg/Arg: p = 0.248; OR = 1.237, 95% CI = 0.862 to 1.773), dominant (Pro/Pro+Arg/Pro vsArg/Arg: p = 0.699; OR = 1.089, 95% CI = 0.706 to 1.681), and recessive (Pro/Pro vs Arg/Arg+Arg/Pro: p = 0.329; OR = 0.754, 95% CI = 0.428 to 1.329) genetic models, respectively. Also, in the stratified analysis by ethnicity, no significant association of this polymorphism with risk of OC was found in the Caucasian population.Conclusions
This meta-analysis suggested that codon 72 of the p53 Arg>Pro polymorphism may not significantly contribute in ovary cancer susceptibility. However, future large studies with gene-gene and gene-environment interactions are needed to validate these findings. 相似文献144.
145.
146.
Whole-genome characterization of lung adenocarcinomas lacking alterations in the RTK/RAS/RAF pathway
Jian Carrot-Zhang Xiaotong Yao Siddhartha Devarakonda Aditya Deshpande Jeffrey S. Damrauer Tiago Chedraoui Silva Christopher K. Wong Hyo Young Choi Ina Felau A. Gordon Robertson Mauro A.A. Castro Lisui Bao Esther Rheinbay Eric Minwei Liu Tuan Trieu David Haan Christina Yau Toshinori Hinoue Marcin Imielinski 《Cell reports》2021,34(8):108784
147.
Sehgal AK Das S Noto K Saier MH Elkan C 《IEEE/ACM transactions on computational biology and bioinformatics / IEEE, ACM》2011,8(3):851-857
With well over 1,000 specialized biological databases in use today, the task of automatically identifying novel, relevant data for such databases is increasingly important. In this paper, we describe practical machine learning approaches for identifying MEDLINE documents and Swiss-Prot/TrEMBL protein records, for incorporation into a specialized biological database of transport proteins named TCDB. We show that both learning approaches outperform rules created by hand by a human expert. As one of the first case studies involving two different approaches to updating a deployed database, both the methods compared and the results will be of interest to curators of many specialized databases. 相似文献
148.
Zong Z Desai SD Kaushal AM Barich DH Huang HS Munson EJ Suryanarayanan R Kirsch LE 《AAPS PharmSciTech》2011,12(3):924-931
Gabapentin is known to undergo intramolecular cyclization to form a lactam (gaba-l) with concomitant loss of water. Gabapentin was milled in a planetary mill for 15–60 min. Unmilled and milled gabapentin
were stored at 50°C with relative humidity ranged between 5% and 90%. The unmilled and milled samples were assayed for gabapentin
and gaba-l by reversed phase-high-performance liquid chromatography and also subjected to powder X-ray diffraction, solid-state nuclear
magnetic resonance and surface area analyses. The rates of lactamization in the milled gabapentin samples correlated to increased
surface area, milling duration, and in-process lactam levels. This effect of milling could not be explained solely by the
increase in surface area with increased milling time but was more likely due to increased regions of crystal disorder caused
by the mechanical and thermal milling stresses. The lactamization rate of milled gabapentin samples was greatest in the presence
of the lowest humidity conditions and dramatically decreased with increasing humidity. In particular, milled gabapentin appeared
to be much more stable at humidity levels greater than 31% RH. This finding could not be attributed to the possibility of
lactam hydrolysis at high humidity but rather to a competitive annealing process wherein milling-induced crystal defects were
lost upon exposure to atmospheric moisture thereby stabilizing the milling-damaged drug substance. 相似文献
149.
150.
Gursharan Singh Aditya Bhalla Paramjit Kaur Neena Capalash Prince Sharma 《Reviews in Environmental Science and Biotechnology》2011,10(4):309-326
Laccases (benzenediol: oxygen oxidoreductase, EC 1.10.3.2) are multi-copper-containing enzymes capable of catalyzing the oxidation
of a wide range of phenolic and non phenolic aromatic compounds. The available data indicates that laccases from prokaryotes
are promising biological tools for green chemistry based applications, especially in decolorization of industrial textile
dye effluents which constitute a major threat to soil and ground water reservoirs worldwide. Another appropriate application
of prokaryotic laccases is bio-bleaching of different kind of pulps where there is indiscriminate use of hazardous chlorine
based chemicals for brightness of the paper. In recent years, researchers have shown interest in the identification and characterization
of laccases from prokaryotic sources. This catalyst is not commonly reported from this kingdom, although prokaryotes have
immense environmental adaptability and biochemical versatility. Moreover, true laccases or laccase-like enzymes exist in many
gram-negative, gram-positive bacteria and actinomycetes. Corresponding genes have been identified and functionally expressed
in genetically developed hosts. This review summarizes the research efforts to characterize laccases and their properties
from different prokaryotic sources, including bacteria and actinomycetes. 相似文献