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171.
A method of holding tachinid puparia in individual gelatin capsules securely held in holes in an expanded polystyrene block,
and the advantages in handling, shipping, and collection of emerging insects are described.
Résumé Il est décrit une méthode d'enrobage des pupes de tachinaires dans des capsules individuelles en gélatine, incluses dans un bloc de polystyrène expansé. Les avantages pour l'emballage, l'envoi par bateau et la récolte des insectes qui sortent de ces pupes sont présentés.相似文献
172.
Edilia Tapia Fernando García-Arroyo Octaviano Silverio Alma N. Rodríguez-Alcocer Ana B. Jiménez-Flores Magdalena Cristobal 《Free radical research》2016,50(7):781-792
Increased oxidative stress and inflammation have an important role in the pathophysiology of chronic kidney disease (CKD). On the other hand, more affordable therapeutic alternatives for treating this disease are urgently needed. Therefore, we compared the therapeutic efficacy of curcumin and mycophenolate mofetil (MMF) in 5/6 nephrectomy (5/6 Nx) model of CKD. Also, we evaluated whether both compounds provide benefit through the preservation of similar antioxidant mechanisms. Four groups of male Wistar were studied over a period of 4 wk. Control sham group (n=?12), 5/6 Nx (n?=?12), 5/6 Nx?+?MMF (30?mg/k BW/day, n?=?11) and 5/6 Nx?+?Curcumin (120?mg/k BW/day, n?=?12). Renal function and markers of oxidative stress and inflammation were evaluated. Also Nrf2-Keap1 and renal dopamine, antioxidant pathways were assessed. 5/6 Nx induced an altered renal autoregulation response, proteinuria, and hypertension; these effects were in association with increased oxidative stress, endothelial dysfunction and renal inflammation. The mechanisms associated with these alterations included a reduced nuclear translocation of Nrf2 and hyperphosphorylation of dopamine D1 receptor with a concurrent overactivation of renal NADPH oxidase. Treatments with MMF and curcumin provided equivalent therapeutic efficacy as both prevented functional renal alterations as well as preserved antioxidant capacity and avoided renal inflammatory infiltration. Moreover, both treatments preserved Nrf2-Keap1 and renal dopamine antioxidant pathways. In summary, therapeutic strategies aimed to preserve renal antioxidant pathways can help to retard the progression of CKD. 相似文献
173.
Vito A. G. Ricigliano Renato Umeton Lorenzo Germinario Eleonora Alma Martina Briani Noemi Di Segni Dalma Montesanti Giorgia Pierelli Fabiana Cancrini Cristiano Lomonaco Francesca Grassi Gabriella Palmieri Marco Salvetti 《PloS one》2013,8(8)
The factual value of genome-wide association studies (GWAS) for the understanding of multifactorial diseases is a matter of intense debate. Practical consequences for the development of more effective therapies do not seem to be around the corner. Here we propose a pragmatic and objective evaluation of how much new biology is arising from these studies, with particular attention to the information that can help prioritize therapeutic targets. We chose multiple sclerosis (MS) as a paradigm disease and assumed that, in pre-GWAS candidate-gene studies, the knowledge behind the choice of each gene reflected the understanding of the disease prior to the advent of GWAS. Importantly, this knowledge was based mainly on non-genetic, phenotypic grounds. We performed single-gene and pathway-oriented comparisons of old and new knowledge in MS by confronting an unbiased list of candidate genes in pre-GWAS association studies with those genes exceeding the genome-wide significance threshold in GWAS published from 2007 on. At the single gene level, the majority (94 out of 125) of GWAS-discovered variants had never been contemplated as plausible candidates in pre-GWAS association studies. The 31 genes that were present in both pre- and post-GWAS lists may be of particular interest in that they represent disease-associated variants whose pathogenetic relevance is supported at the phenotypic level (i.e. the phenotypic information that steered their selection as candidate genes in pre-GWAS association studies). As such they represent attractive therapeutic targets. Interestingly, our analysis shows that some of these variants are targets of pharmacologically active compounds, including drugs that are already registered for human use. Compared with the above single-gene analysis, at the pathway level GWAS results appear more coherent with previous knowledge, reinforcing some of the current views on MS pathogenesis and related therapeutic research. This study presents a pragmatic approach that helps interpret and exploit GWAS knowledge. 相似文献
174.
Anthropologists have neglected a significant dimension to religion by ignoring the spiritual lives of a society's youngest members. In Cote d'lvoire, Beng infants are said to lead a profoundly spiritual existence. Indeed, until the age of five or so, Beng children are said to live at least part of the time in the spiritual other world ( wrugbe ) they inhabited before being reincarnated. Exploring both ideology and praxis, the author probes the consequences for the daily experiences and care of Bang babies, including umbilical cord care, enemas, crying, adornment, naming, personality development, and infant disease and death. The author concludes by considering the implications of a full-blown treatment of infants for the practice of anthropology. 相似文献
175.
Antonio Martínez-Gutierrez Berenice Carbajal-Lopez Triet M. Bui Monica Mendoza-Rodriguez Alma D. Campos-Parra Germán Calderillo-Ruiz David Cantú-De Leon Eduardo-Osiris Madrigal-Santillán Ronen Sumagin Carlos Pérez-Plasencia Eloy-Andrés Pérez-Yépez 《Biochemistry and Biophysics Reports》2022
Colon cancer (CC) is the third most common neoplasm and the fourth cause of cancer-related death worldwide in both sexes. It has been established that inflammation plays a critical role in tumorigenesis and progression of CC. Immune, stromal and tumor cells supply the tumor microenvironment with pro-inflammatory cytokines such as interleukin 1β, TNFα, IL-6 and IL-11, to hyperactivate signaling pathways linked to cancerous processes. Recent findings suggest a putative role of microRNAs (miRNAs) in the progression and management of the inflammatory response in intestinal diseases. Moreover, miRNAs are able to regulate expression of molecular mediators that are linking inflammation and cancer. In this work a miRNA panel differentially expressed between healthy, inflammatory bowel disease (IBD) and CC tissue was established. Identified miRNAs regulate signaling pathways related to inflammation and cancer progression. An inflammation associated-miRNA panel composed of 11-miRNAs was found to be overexpressed in CC but not in inflamed or normal tissues (miR-21-5p, miR-304-5p, miR-577, miR-335-5p, miR-21-3p, miR-27b-5p, miR-335-3p, miR-215-5p, miR-30b-5p, miR-192-5p, miR-3065-5p). The association of top hit miRNAs, miR-3065-5p and miR-30b-5p expression with overall survival of CC patients was demonstrated using Kaplan-Meier tests. Finally, differential miRNA expression was validated using an inflammation-associated CC model induced by Azoxymethane/Dextran Sodium Sulfate (AOM/DSS) to compare miRNA expression in normal and inflamed tissue versus CC tissues. Based on these findings we propose the identified inflammatory miRNA panel as a potent diagnostic tool for CC determination. 相似文献
176.
177.
C Díaz-Pérez JS Rodríguez-Zavala AL Díaz-Pérez J Campos-García 《World journal of microbiology & biotechnology》2012,28(3):1185-1191
Pseudomonas aeruginosa is a versatile bacterium that can grow using citronellol or leucine as sole carbon source. For both compounds the degradation
pathways converge at the key enzyme 3-methylcrotonyl coenzyme-A carboxylase (MCCase). This enzyme is a complex formed by two
subunits (α and β), encoded by the liuD and liuB genes, respectively; both are essential for enzyme function. Previously, both subunits had been separately expressed and
then the complex re-constituted, however this methodology is laborious and produces low yield of active enzyme. In this work,
the MCCase subunits were co-expressed in the same plasmid and purified in one step by affinity chromatography using the LiuD-His
tag protein, interacting with the LiuB-S tag recombinant protein. The purified enzyme lost most of the activity within few
hours of storage. The co-expressed subunits formed an (αβ)4 complex that suffered a modification of its oligomerization state after storage, which probably contributed to the loss on
activity observed. The recombinant MCCase enzyme presented optimum pH and temperature values of 9.0 and 30o C, respectively.
Functionally, MCCase showed Michaelian kinetics behavior with a Km for its substrate and Vmax of 168 μM and 430 nmoles mg−1min−1, respectively. The results suggest that the co-expression and co-purification of the subunits is a suitable procedure to
obtain the active complex of the MCCase from Pseudomonas aeruginosa in a single step. 相似文献
178.
179.
System approaches to elucidate ecosystem functioning constitute an emerging area of research within microbial ecology. Such approaches aim at investigating all levels of biological information (DNA, RNA, proteins and metabolites) to capture the functional interactions occurring in a given ecosystem and track down characteristics that could not be accessed by the study of isolated components. In this context, the study of the proteins collectively expressed by all the microorganisms present within an ecosystem (metaproteomics) is not only crucial but can also provide insights into microbial functionality. Overall, the success of metaproteomics is closely linked to metagenomics, and with the exponential increase in the availability of metagenome sequences, this field of research is starting to experience generation of an overwhelming amount of data, which requires systematic analysis. Metaproteomics has been employed in very diverse environments, and this review discusses the recent advances achieved in the context of human biology, soil, marine and freshwater environments as well as natural and bioengineered systems. 相似文献
180.
Al-Ramahi I Lam YC Chen HK de Gouyon B Zhang M Pérez AM Branco J de Haro M Patterson C Zoghbi HY Botas J 《The Journal of biological chemistry》2006,281(36):26714-26724
CHIP (C terminus of Hsc-70 interacting protein) is an E3 ligase that links the protein folding machinery with the ubiquitin-proteasome system and has been implicated in disorders characterized by protein misfolding and aggregation. Here we investigate the role of CHIP in protecting from ataxin-1-induced neurodegeneration. Ataxin-1 is a polyglutamine protein whose expansion causes spinocerebellar ataxia type-1 (SCA1) and triggers the formation of nuclear inclusions (NIs). We find that CHIP and ataxin-1 proteins directly interact and co-localize in NIs both in cell culture and SCA1 postmortem neurons. CHIP promotes ubiquitination of expanded ataxin-1 both in vitro and in cell culture. The Hsp70 chaperone increases CHIP-mediated ubiquitination of ataxin-1 in vitro, and the tetratricopeptide repeat domain, which mediates CHIP interactions with chaperones, is required for ataxin-1 ubitiquination in cell culture. Interestingly, CHIP also interacts with and ubiquitinates unexpanded ataxin-1. Overexpression of CHIP in a Drosophila model of SCA1 decreases the protein steady-state levels of both expanded and unexpanded ataxin-1 and suppresses their toxicity. Finally we investigate the ability of CHIP to protect against toxicity caused by expanded polyglutamine tracts in different protein contexts. We find that CHIP is not effective in suppressing the toxicity caused by a bare 127Q tract with only a short hemagglutinin tag, but it is very efficient in suppressing toxicity caused by a 128Q tract in the context of an N-terminal huntingtin backbone. These data underscore the importance of the protein framework for modulating the effects of polyglutamine-induced neurodegeneration. 相似文献