全文获取类型
收费全文 | 197篇 |
免费 | 12篇 |
国内免费 | 1篇 |
出版年
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 7篇 |
2020年 | 4篇 |
2019年 | 4篇 |
2018年 | 2篇 |
2017年 | 4篇 |
2016年 | 8篇 |
2015年 | 8篇 |
2014年 | 14篇 |
2013年 | 14篇 |
2012年 | 16篇 |
2011年 | 11篇 |
2010年 | 14篇 |
2009年 | 12篇 |
2008年 | 6篇 |
2007年 | 8篇 |
2006年 | 4篇 |
2005年 | 4篇 |
2004年 | 4篇 |
2003年 | 5篇 |
2002年 | 2篇 |
2001年 | 4篇 |
2000年 | 4篇 |
1999年 | 8篇 |
1998年 | 11篇 |
1997年 | 4篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有210条查询结果,搜索用时 15 毫秒
201.
Adan Cabal-Prieto Lucía Sánchez-Arellano José Andrés Herrera-Corredor Jesús Rodríguez-Miranda Witoon Prinyawiwatkul Lorena Guadalupe Ramón-Canul Filiberto Toledano-Toledano Ingrid Mayanin Rodríguez-Buenfil Manuel Octavio Ramírez-Sucre Gregorio Hernández-Salinas Emmanuel de Jesús de Ramírez-Rivera 《Journal of sensory studies》2023,38(1):e12798
202.
203.
Avise JC; Shapira JF; Daniel SW; Aquadro CF; Lansman RA 《Molecular biology and evolution》1983,1(1):38-56
We address the problem of the possible significance of biological
speciation to the magnitude and pattern of divergence of asexually
transmitted characters in bisexual species. The empirical data for this
report consist of restriction endonuclease site variability in maternally
transmitted mitochondrial DNA (mtDNA) isolated from 82 samples of
Peromyscus polionotus and P. leucopus collected from major portions of the
respective species' ranges. Data are analyzed together with previously
published information on P. maniculatus, a sibling species to polionotus.
Maps of restriction sites indicate that all of the variation observed can
be reasonably attributed to base substitutions leading to loss or gain of
particular recognition sites. Magnitude of mtDNA sequence divergence within
polionotus (maximum approximately equal to 2%) is roughly comparable to
that observed within any of five previously identified mtDNA assemblages in
maniculatus. Sequence divergence within leucopus (maximum approximately
equal to 4%) is somewhat greater than that within polionotus. Consideration
of probable evolutionary links among mtDNA restriction site maps allowed
estimation of matriarchal phylogenies within polionotus and leucopus.
Clustering algorithms and qualitative Wagner procedures were used to
generate phenograms and parsimony networks, respectively, for the
between-species comparisons. Three simple graphical models are presented to
illustrate some conceivable relationships of mtDNA differentiation to
speciation. In theoretical case I, each of two reproductively defined
species (A and B) is monophyletic in matriarchal genealogy; the common
female ancestor of either species can either predate or postdate the
speciation. In case II, neither species is monophyletic in matriarchal
genotype. In case III, species B is monophyletic but forms a subclade
within A which is thus paraphyletic with respect to B. The empirical
results for mtDNA in maniculatus and polionotus appear to conform closely
to case III. These theoretical and empirical considerations raise a number
of questions about the general relationship of the speciation process to
the evolution of uniparentally transmitted traits. Some of these
considerations are presented, and it is suggested that the distribution
patterns of mtDNA sequence variation within and among extant species should
be of considerable relevance to the particular demographies of speciation.
相似文献
204.
Involvement of aberrant cyclin‐dependent kinase 5/p25 activity in experimental traumatic brain injury
下载免费PDF全文
![点击此处可从《Journal of neurochemistry》网站下载免费的PDF全文](/ch/ext_images/free.gif)
205.
206.
W.J. Rietveld J.M. Waterhouse Ana Adan Helena Almirall 《Biological Rhythm Research》2013,44(3):161-248
207.
Starley B. Shade Valerie B. Kirby Sally Stephens Lissa Moran Edwin D. Charlebois Jessica Xavier Adan Cajina Wayne T. Steward Janet J. Myers 《PLoS medicine》2021,18(5)
BackgroundIn the United States, patients with HIV face significant barriers to linkage to and retention in care which impede the necessary steps toward achieving the desired clinical outcome of viral suppression. Individual-level interventions, such as patient navigation, are evidence based, effective strategies for improving care engagement. In addition, use of surveillance and clinical data to identify patients who are not fully engaged in care may improve the effectiveness and cost-effectiveness of these programs.Methods and findingsWe employed a pre-post design to estimate the outcomes and costs, from the program perspective, of 5 state-level demonstration programs funded under the Health Resources and Services Administration’s Special Projects of National Significance Program (HRSA/SPNS) Systems Linkages Initiative that employed existing surveillance and/or clinical data to identify individuals who had never entered HIV care, had fallen out of care, or were at risk of falling out of care and navigation strategies to engage patients in HIV care. Outcomes and costs were measured relative to standard of care during the first year of implementation of the interventions (2013 to 2014). We followed patients to estimate the number and proportion of additional patients linked, reengaged, retained, and virally suppressed by 12 months after enrollment in the interventions. We employed inverse probability weighting to adjust for differences in patient characteristics across programs, missing data, and loss to follow-up. We estimated the additional costs expended during the first year of each intervention and the cost per outcome of each intervention as the additional cost per HIV additional care continuum target achieved (cost per patient linked, reengaged, retained, and virally suppressed) 12 months after enrollment in each intervention. In this study, 3,443 patients were enrolled in Louisiana (LA), Massachusetts (MA), North Carolina (NC), Virginia (VA), and Wisconsin (WI) (147, 151, 2,491, 321, and 333, respectively). Patients were a mean of 40 years old, 75% male, and African American (69%) or Caucasian (22%). At baseline, 24% were newly diagnosed, 2% had never been in HIV care, 45% had fallen out of care, and 29% were at risk of falling out of care. All 5 interventions were associated with increases in the number and proportion of patients with viral suppression [percent increase: LA = 90.9%, 95% confidence interval (CI) = 88.4 to 93.4; MA = 78.1%, 95% CI = 72.4 to 83.8; NC = 47.5%, 95% CI = 45.2 to 49.8; VA = 54.6, 95% CI = 49.4 to 59.9; WI = 58.4, 95% CI = 53.4 to 63.4]. Overall, interventions cost an additional $4,415 (range = $3,746 to $5,619), $2,009 (range = $1,516 to $2,274), $920 (range = $627 to $941), $2,212 (range = $1,789 to $2,683), and $3,700 ($2,734 to $4,101), respectively per additional patient virally suppressed. The results of this study are limited in that we did not have contemporaneous controls for each intervention; thus, we are only able to assess patients against themselves at baseline and not against standard of care during the same time period.ConclusionsPatient navigation programs were associated with improvements in engagement of patients in HIV care and viral suppression. Cost per outcome was minimized in states that utilized surveillance data to identify individuals who were out of care and/or those that were able to identify a larger number of patients in need of improvement at baseline. These results have the potential to inform the targeting and design of future navigation-type interventions.Starley Shade and co-workers study outcomes and costs associated with interventions seeking to improve engagement with HIV care in the United States. 相似文献
208.
The replicative helicase MCM recruits cohesin acetyltransferase ESCO2 to mediate centromeric sister chromatid cohesion
下载免费PDF全文
![点击此处可从《The EMBO journal》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Miroslav P Ivanov Rene Ladurner Ina Poser Rebecca Beveridge Evelyn Rampler Otto Hudecz Maria Novatchkova Jean‐Karim Hériché Gordana Wutz Petra van der Lelij Emanuel Kreidl James RA Hutchins Heinz Axelsson‐Ekker Jan Ellenberg Anthony A Hyman Karl Mechtler Jan‐Michael Peters 《The EMBO journal》2018,37(15)
Chromosome segregation depends on sister chromatid cohesion which is established by cohesin during DNA replication. Cohesive cohesin complexes become acetylated to prevent their precocious release by WAPL before cells have reached mitosis. To obtain insight into how DNA replication, cohesion establishment and cohesin acetylation are coordinated, we analysed the interaction partners of 55 human proteins implicated in these processes by mass spectrometry. This proteomic screen revealed that on chromatin the cohesin acetyltransferase ESCO2 associates with the MCM2‐7 subcomplex of the replicative Cdc45‐MCM‐GINS helicase. The analysis of ESCO2 mutants defective in MCM binding indicates that these interactions are required for proper recruitment of ESCO2 to chromatin, cohesin acetylation during DNA replication, and centromeric cohesion. We propose that MCM binding enables ESCO2 to travel with replisomes to acetylate cohesive cohesin complexes in the vicinity of replication forks so that these complexes can be protected from precocious release by WAPL. Our results also indicate that ESCO1 and ESCO2 have distinct functions in maintaining cohesion between chromosome arms and centromeres, respectively. 相似文献
209.
The destruction of periodontal tissues during periodontitis is the result of the immune-inflammatory reactions to the bacteria of dental biofilm. Probiotics may reduce dysbiosis by the modification of the dental microbiome, which can influence the immune-inflammatory mechanisms. The aim of this study was to estimate the clinical and microbiological parameters, before and after 30 days of application of the dietary supplement containing Lactobacillus salivarius SGL03 or placebo. The study was conducted in 51 patients with stage I or II periodontitis during the maintenance phase of treatment. The clinical parameters and the number of colony forming units (CFU) of bacteria in supragingival plaque were assessed before and after 30 days of the oral once daily administration of the dietary supplement in the form of suspension containing L. salivarius SGL03 or placebo. There were no changes in the PI scores between and within the groups. The value of BOP decreased in both groups. In the study group the significant reduction of the mean pocket depth was revealed (from 2.5 to 2.42, p = 0,027) but without the difference between the groups. There were no significant changes in the number of bacteria within the groups. In the control, but not the study group, positive correlations were observed between the clinical parameters (variables) and the number of bacteria. The use of the dietary supplement containing L. salivarius SGL03 may reduce pocket depth despite the lack of changes in other clinical parameters and the number of bacteria in supragingival plaque.Key words: probiotics, periodontal treatment, Lactobacillus salivarius 相似文献
210.