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71.
In Drosophila, development of the embryonic germ cells depends on posterior transport and site-specific translation of oskar (osk) mRNA and on interdependent anchoring of the osk mRNA and protein within the posterior subcortical region of the oocyte. Transport of the osk mRNA is mediated by microtubules, while anchoring of the osk gene products at the posterior pole of the oocyte is suggested to be microfilament dependent. To date, only a single actin binding protein (TropomyosinII) has been identified with a putative role in osk mRNA and protein anchoring. This communication demonstrates that mutations in the Drosophila moesin (Dmoe) gene that encodes another actin binding protein result in delocalization of osk mRNA and protein from the posterior subcortical region and, as a consequence, in failure of embryonic germ cell development. In Dmoe mutant oocytes, the subcortical actin network is detached from the cell membrane, while the polarized microtubule cytoskeleton is unaffected. In line with the earlier observations, colocalization of ectopic actin and OSK protein in Dmoe mutants suggests that the actin cytoskeleton anchors OSK protein to the subcortical cytoplasmic area of the Drosophila oocyte. 相似文献
72.
Corticotropin-releasing factor (CRF) and the urocortins (UCNs) are structurally and pharmacologically related neuropeptides which regulate the endocrine, autonomic, emotional and behavioral responses to stress. CRF and UCN1 activate both CRF receptors (CRFR1 and CRFR2) with CRF binding preferentially to CRFR1 and UCN1 binding equipotently to both receptors. UCN2 and UCN3 activate selectively CRFR2. Previously an in vitro study demonstrated that superfusion of both CRF and UCN1 elevated the GABA release elicited by electrical stimulation from rat amygdala, through activation of CRF1 receptors. In the present experiments, the same in vitro settings were used to study the actions of CRF and the urocortins on hypothalamic GABA release. CRF and UCN1 administered in equimolar doses increased significantly the GABA release induced by electrical stimulation from rat hypothalamus. The increasing effects of CRF and UCN1 were inhibited considerably by the selective CRFR1 antagonist antalarmin, but were not influenced by the selective CRFR2 antagonist astressin 2B. UCN2 and UCN3 were ineffective. We conclude that CRF1 receptor agonists induce the release of GABA in the hypothalamus as well as previously the amygdala. We speculate that CRF-induced GABA release may act as a double-edged sword: amygdalar GABA may disinhibit the hypothalamic CRF release, leading to activation of the hypothalamic-pituitary-adrenal axis, whereas hypothalamic GABA may inhibit the hypothalamic CRF release, terminating this activation. 相似文献
73.
74.
Hegyi M Félné Semsei A Jakab Z Antal I Kiss J Szendrõi M Csóka M Kovács G 《Magyar onkologia》2012,56(1):30-37
The objective of this report was to estimate long-term outcome and prognostic factors in children and adolescents with osteosarcoma. To evaluate the efficacy of surgery and multiagent chemotherapy for treating osteosarcoma, we reviewed 122 cases (65 males, 57 females, mean age 13.8 ± 3.6 years) treated at the Second Department of Pediatrics in Budapest between 1988 and 2006. Demographic parameters, tumor-related and treatment-related variables, response, overall survival (OS) and event-free survival (EFS) were analyzed. The 5-year OS and EFS were 68% and 61.5%, respectively. OS of patients without metastasis was 79%, while OS with early metastasis was 17%. Survival of patients with amputation (n=30) was not significantly different from that of patients with limb-salvage surgery (n=82), but all patients without radical surgery died. Gender and histological classification had no prognostic significance. Patients with localized tumors in extremities had increased survival compared to those with axial skeleton tumors (p=0.013). Poor histological response to neoadjuvant chemotherapy (rate of survivor tumor cells >10%) was associated with decreased survival (p=0.018). Patients under 14 years had better EFS than patients over 14 years (p=0.008). Our results demonstrate that younger patients with localized osteosarcoma of the extremities who receive limb-salvage surgery and chemotherapy have an excellent survival. 相似文献
75.
Peter M Szabó Miklós Pintér Diana Rita Szabó Adrienn Zsippai Attila Patócs András Falus Károly Rácz Peter Igaz 《BMC medical genomics》2012,5(1):1-19
Background
Pheochromocytoma and neuroblastoma are the most common neural crest-derived tumors in adults and children, respectively. We have performed a large-scale in silico analysis of altogether 1784 neuroblastoma and 531 pheochromocytoma samples to establish similarities and differences using analysis of mRNA and microRNA expression, chromosome aberrations and a novel bioinformatics analysis based on cooperative game theory.Methods
Datasets obtained from Gene Expression Omnibus and ArrayExpress have been subjected to a complex bioinformatics analysis using GeneSpring, Gene Set Enrichment Analysis, Ingenuity Pathway Analysis and own software.Results
Comparison of neuroblastoma and pheochromocytoma with other tumors revealed the overexpression of genes involved in development of noradrenergic cells. Among these, the significance of paired-like homeobox 2b in pheochromocytoma has not been reported previously. The analysis of similar expression patterns in neuroblastoma and pheochromocytoma revealed the same anti-apoptotic strategies in these tumors. Cancer regulation by stathmin turned out to be the major difference between pheochromocytoma and neuroblastoma. Underexpression of genes involved in neuronal cell-cell interactions was observed in unfavorable neuroblastoma. By the comparison of hypoxia- and Ras-associated pheochromocytoma, we have found that enhanced insulin like growth factor 1 signaling may be responsible for the activation of Src homology 2 domain containing transforming protein 1, the main co-factor of RET. Hypoxia induced factor 1?? and vascular endothelial growth factor signaling included the most prominent gene expression changes between von Hippel-Lindau- and multiple endocrine neoplasia type 2A-associated pheochromocytoma.Conclusions
These pathways include previously undescribed pathomechanisms of neuroblastoma and pheochromocytoma and associated gene products may serve as diagnostic markers and therapeutic targets. 相似文献76.
Miklós Müller Marek Mentel Jaap J. van Hellemond Katrin Henze Christian Woehle Sven B. Gould Re-Young Yu Mark van der Giezen Aloysius G. M. Tielens William F. Martin 《Microbiology and molecular biology reviews》2012,76(2):444-495
Summary: Major insights into the phylogenetic distribution, biochemistry, and evolutionary significance of organelles involved in ATP synthesis (energy metabolism) in eukaryotes that thrive in anaerobic environments for all or part of their life cycles have accrued in recent years. All known eukaryotic groups possess an organelle of mitochondrial origin, mapping the origin of mitochondria to the eukaryotic common ancestor, and genome sequence data are rapidly accumulating for eukaryotes that possess anaerobic mitochondria, hydrogenosomes, or mitosomes. Here we review the available biochemical data on the enzymes and pathways that eukaryotes use in anaerobic energy metabolism and summarize the metabolic end products that they generate in their anaerobic habitats, focusing on the biochemical roles that their mitochondria play in anaerobic ATP synthesis. We present metabolic maps of compartmentalized energy metabolism for 16 well-studied species. There are currently no enzymes of core anaerobic energy metabolism that are specific to any of the six eukaryotic supergroup lineages; genes present in one supergroup are also found in at least one other supergroup. The gene distribution across lineages thus reflects the presence of anaerobic energy metabolism in the eukaryote common ancestor and differential loss during the specialization of some lineages to oxic niches, just as oxphos capabilities have been differentially lost in specialization to anoxic niches and the parasitic life-style. Some facultative anaerobes have retained both aerobic and anaerobic pathways. Diversified eukaryotic lineages have retained the same enzymes of anaerobic ATP synthesis, in line with geochemical data indicating low environmental oxygen levels while eukaryotes arose and diversified. 相似文献
77.
Katalin Adrienna Kékesi Gábor Juhász Attila Simor Péter Gulyássy éva Mónika Szeg? éva Hunyadi-Gulyás Zsuzsanna Darula Katalin F. Medzihradszky Miklós Palkovits Botond Penke András Czurkó 《PloS one》2012,7(12)
Probing molecular brain mechanisms related to increased suicide risk is an important issue in biological psychiatry research. Gene expression studies on post mortem brains indicate extensive changes prior to a successful suicide attempt; however, proteomic studies are scarce. Thus, we performed a DIGE proteomic analysis of post mortem tissue samples from the prefrontal cortex and amygdala of suicide victims to identify protein changes and biomarker candidates of suicide. Among our matched spots we found 46 and 16 significant differences in the prefrontal cortex and amygdala, respectively; by using the industry standard t test and 1.3 fold change as cut off for significance. Because of the risk of false discoveries (FDR) in these data, we also made FDR adjustment by calculating the q-values for all the t tests performed and by using 0.06 and 0.4 as alpha thresholds we reduced the number of significant spots to 27 and 9 respectively. From these we identified 59 proteins in the cortex and 11 proteins in the amygdala. These proteins are related to biological functions and structures such as metabolism, the redox system, the cytoskeleton, synaptic function, and proteolysis. Thirteen of these proteins (CBR1, DPYSL2, EFHD2, FKBP4, GFAP, GLUL, HSPA8, NEFL, NEFM, PGAM1, PRDX6, SELENBP1 and VIM,) have already been suggested to be biomarkers of psychiatric disorders at protein or genome level. We also pointed out 9 proteins that changed in both the amygdala and the cortex, and from these, GFAP, INA, NEFL, NEFM and TUBA1 are interacting cytoskeletal proteins that have a functional connection to glutamate, GABA, and serotonin receptors. Moreover, ACTB, CTSD and GFAP displayed opposite changes in the two examined brain structures that might be a suitable characteristic for brain imaging studies. The opposite changes of ACTB, CTSD and GFAP in the two brain structures were validated by western blot analysis. 相似文献
78.
Laczik M Tukacs E Uzonyi B Domokos B Doma Z Kiss M Horváth A Batta Z Maros-Szabó Z Török Z 《Bioinformation》2012,8(2):107-109
The ever evolving Next Generation Sequencing technology is calling for new and innovative ways of data processing and visualization. Following a detailed survey of the current needs of researchers and service providers, the authors have developed GenoViewer: a highly user-friendly, easy-to-operate SAM/BAM viewer and aligner tool. GenoViewer enables fast and efficient NGS assembly browsing, analysis and read mapping. It is highly customized, making it suitable for a wide range of NGS related tasks. Due to its relatively simple architecture, it is easy to add specialised visualization functionalities, facilitating further customised data analysis. The software's source code is freely available; it is open for project and task-specific modifications. AVAILABILITY: The database is available for free at http://www.genoviewer.com/ 相似文献
79.
Forgách P Bakonyi T Tapaszti Z Nowotny N Rusvai M 《Journal of invertebrate pathology》2008,98(2):235-238
A survey on the occurrence of six honeybee-pathogenic viruses was carried out using one-step RT-PCR assays. Samples were collected between 1999 and 2004 in 52 Hungarian apiaries located in different regions of the country. The results of the assays on samples of adult honeybees and Varroa destructor mites were compared to similar surveys from France and Austria. The study demonstrates geographical differences in the prevalence of honeybee viruses between Hungary and the older EU member states. The results could serve as a basis for monitoring further changes in the distribution of honeybee viruses in Europe. 相似文献
80.
In the non-surgical treatment of head and neck tumours, the "organ preserving" modalities have become more and more important. At present radiotherapy is the most important means of this kind of treatment. In the radiotherapy of head and neck cancer local dose escalation is an important factor in increasing local tumour control. However, with sole external beam irradiation it is difficult to spare adjacent normal tissues. Interstitial brachytherapy (BT) is ideally suited to deliver a high dose limited to the volume of the primary tumour, thus maximizing tumour control while minimizing complications. Low-dose-rate (LDR) BT, which has been applied for a long time in the treatment of these tumours, is now challenged by high-dose-rate (HDR) and pulsed-dose-rate (PDR) BT. The purpose of this work is to show the role and the indications of BT in tumours of the head and neck region and to offer general and site-specific recommendations based upon the available information from the literature. 相似文献