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681.
Epigastrius with omphalocele--report of a case 总被引:1,自引:0,他引:1
An epigastrius (parasitic twinning in the epigastrium) was delivered via the vaginal route spontaneously and died 37 days later. The autosite had cardiac hypertrophy with VSD, PDA, and PFO and an omphalocele. The liver was partly conjoined. There was a small swelling at the lower part of the autosite's bifurcated sternum to which the parasitic left pelvis and lower extremity were attached. On the second day after birth, parasitectomy was performed. The amputated specimens consisted of a small left pelvic girdle with a free extremity, a scrotal mass, nipplelike structures and two small protuberances externally. The liver, intestines, two testes, one kidney, one ureter, and the bladder were contained within the omphalocele. Although all of the organs and external structures of the parasite had abnormal histopathological findings, differentiated muscle fibers and submucous and/or myenteric plexus were observed. 相似文献
682.
Cephalomonas ( Cp .) granulata N. L. Higinb. (Volvocales, Chlorophyceae), a rare volvocalean phytoflagellate, has recently been isolated from a paddy field in Japan and examined by light and fluorescence microscopy. The vegetative cells of Cp . granulata have granulate loricae and a characteristic mushroom-like shape with a hemispherical to spherical anterior part and narrower posterior part. Cp . granulata has been classified among the Phacotaceae along with other loricated genera. However, its phylogenetic position has not been investigated using molecular phylogeny. To evaluate the phylogenetic position of Cephalomonas , the 18S r RNA gene sequence of the Japanese strain was determined. The phylogenetic analyses revealed that Cp . granulata was not closely related to other loricated taxa with known phylogenetic affinities, such as Phacotaceae sensu stricto ( Phacotus , Pteromonas , and Wislouchiella ) and Dysmorphococcus globosus . This indicates at least three independent origins of loricae within the Volvocales. 相似文献
683.
Nucleic acid bases such as adenine and uracil, and nitrobenzeneboronic acid substituted silicas were prepared by the reaction of chloromethylbenzene substituted silica with adenine sodium salt and trimethylsilylated uracil, and nitration of benzeneboronic acid substituted silica, respectively. From the results of HPLC of nucleosides and N-ethyl derivatives of nucleic acid bases using modified silicas, hydrophobic base stacking interaction, selective hydrogen bonding interaction between purine and pyrimidine bases, and reversible cyclic boronate ester formation between diols of nucleosides with boronic acid were effective for the separation of nucleic acid related compounds. Moreover, association constants for hydrogen bonding formation of nucleic acid bases were estimated. 相似文献
684.
A key common feature of all but three known mammalian genera is the strict seven cervical vertebrae blueprint, suggesting the involvement of strong conserving selection forces during mammalian radiation. This is further supported by reports indicating that children with cervical ribs die before they reach reproductive age. Hypotheses were put up, associating cervical ribs (homeotic transformations) to embryonal cancer (e.g., neuroblastoma) or ascribing the constraint in cervical vertebral count to the development of the mammalian diaphragm. Here, we describe a spontaneous mutation c.196A > G in the Bos taurus T gene (also known as brachyury) associated with a cervical vertebral homeotic transformation that violates the fundamental mammalian cervical blueprint, but does not preclude reproduction of the affected individual. Genome-wide mapping, haplotype tracking within a large pedigree, resequencing of target genome regions, and bioinformatic analyses unambiguously confirmed the mutant c.196G allele as causal for this previously unknown defect termed vertebral and spinal dysplasia (VSD) by providing evidence for the mutation event. The nonsynonymous VSD mutation is located within the highly conserved T box of the T gene, which plays a fundamental role in eumetazoan body organization and vertebral development. To our knowledge, VSD is the first unequivocally approved spontaneous mutation decreasing cervical vertebrae number in a large mammal. The spontaneous VSD mutation in the bovine T gene is the first in vivo evidence for the hypothesis that the T protein is directly involved in the maintenance of the mammalian seven-cervical vertebra blueprint. It therefore furthers our knowledge of the T-protein function and early mammalian notochord development. 相似文献
685.
Shinji Ohsawa Toshiaki Umemura Hiromichi Akahori Tomoyoshi Terada Yoshinori Muto 《Biologia》2018,73(4):415-423
Ten-eleven translocation (TET) proteins, a family of Fe2+- and 2-oxoglutarate-dependent dioxygenases, are involved in DNA demethylation. Three TET paralogs have been identified (TET1, TET2, and TET3) and they show different patterns of tissue-specific expression. In our previous evolutionary studies, we found that the TET1 and TET2 genes underwent positive selection more frequently than the TET3 gene, possibly due to changes in the selective constraints during their evolutionary process. In this study, we performed a network-based analysis of the mRNA expression profiles of TET knockdown and the TET-containing co-expression modules identified in early human developmental stages. Analyses based on the PPI subnetwork demonstrated that TET DEGs PPI subnetwork genes were more evolutionarily conserved than all the human-chimpanzee orthologs during evolutionary history. GO annotation of gene co-expression modules containing a TET gene ortholog revealed particular features of the potential role of TET gene family members. Our study implicated the TET1 module in fundamental aspects of cellular physiology, such as the regulation of glucose metabolism, and the TET2 module in GPCR signal transduction. The TET3 module was related to signaling pathways involved in developmental regulation. The evolutionary rate and phylogenetic age distribution analysis of network member genes also support these network-based analyses. The present study provides an integrated view of TET gene family properties and might be informative for elucidating the molecular mechanisms of their biological functions. 相似文献
686.
Eishi Nagai Takahiro Ogawa Tammy Kielian Akashi Ikubo Tsuneo Suzuki 《Cancer immunology, immunotherapy : CII》1998,47(2):72-80
The specific aim of this study was to examine the prophylactic as well as the therapeutic efficacies of irradiated mouse
CT26 colon cancer cells, infected with recombinant adenoviruses harboring cDNAs specific for granulocyte macrophage-colony-stimulating
factor (GM-CSF), interferon (IFN-γ) and monocyte chemotactic protein1 (MCP-1). Results showed that tumor cells secrete the
respective cytokines for several days after infection and subsequent irradiation. Vaccination with irradiated GM-CSF-secreting
CT26 cells protected 90% of syngeneic mice challenged with live parental cells. On the other hand, vaccination with irradiated
IFNγ or MCP-1-secreting CT26 cells totally failed to protect mice from tumor development after challenge with parental cells.
None of the tumor-free mice initially vaccinated with irradiated GM-CSF-producing CT26 cells developed tumor upon repeated
challenge with parental cells during the entire observation period. The establishment of specific and long-lasting antitumor
immunity following vaccination with GM-CSF-producing tumor cells requires the simultaneous presence of GM-CSF and tumor antigen
at the vaccine site. Depletion of CD8+ cells, but not CD4+ cells, blocked the vaccine efficacy of GM-CSF-producing tumor cells. Subcutaneous injection of irradiated GM-CSF-producing
CT26 cells also effectively prevented the growth of a small load of parental tumor that was implanted 3 days earlier or the
development of metastatic foci in the lung from intravenously injected parental cells either 7 days before or 3 days after
vaccination. Our data thus show that, in these experimental tumor models, subcutaneous injection of irradiated tumor cells
adenovirally, transduced with the GM-CSF gene leads not only to prevention of growth of subsequently implanted tumor but also
to elimination of pre-existing and metastatic tumors. 相似文献