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1.
Identification of a widely distributed 90-kDa glycoprotein that is homologous to the Hermes-1 human lymphocyte homing receptor 总被引:9,自引:0,他引:9
S T Pals F Hogervorst G D Keizer T Thepen E Horst C C Figdor 《Journal of immunology (Baltimore, Md. : 1950)》1989,143(3):851-857
Homing of recirculating lymphocytes from the blood into the lymphoid tissues is mediated by 90-kDa homing receptors on the lymphocyte cell surface, allowing selective binding to specialized endothelium lining high endothelial venules. This study describes two novel mAb, NKI-P1 and NKI-P2, directed against functional epitopes of a human lymphocyte homing receptor, gp90. Biochemical studies demonstrated that these antibodies recognize a 90-kDa glycoprotein which is similar to the Ag recognized by the mAb Hermes-1. This notion was confirmed by immunohistochemical studies showing identical reaction patterns. Furthermore, it was observed that NKI-P1 and NKI-P2 blocked adhesion of lymphocytes to high endothelial venules. Immunohistochemical, immunofluorescence, and immunoprecipitation studies revealed that gp90 is widely expressed on hemopoietic cells including lymphocytes, macrophages/dendritic cells, myeloid cells, and erythrocytes. The gp90 is also expressed on a number of nonhemopoietic cells such as endothelial cells, certain epithelial cells, and fibroblasts. In addition to its expression on normal cells, gp90 is present on a spectrum of tumor cell lines of lymphoid, monocytic, epithelial, glial, and melanocytic origin. In addition to the 90-kDa product, the antibodies immunoprecipitate several polypeptides in the range of 120 to 200 kDa. Interestingly, it was observed that certain mamma tumor cell-line cells lack the 90-kDa polypeptide indicating the heterogeneous expression of the molecules recognized by the antibodies. These results indicate that the 90-kDa glycoprotein homologues of the Hermes-1 human lymphocyte homing receptor are expressed on hemopoietic tissues as well as on a number of nonhemopoietic tissues and tumor cell lines. Although the function of these molecules in nonlymphoid cells is presently unknown, they might play a role in cell-cell or cell-matrix adhesion. 相似文献
2.
Arjan W. Griffioen Eveliene Horst Karl Heinz Heider Vera J. M. Wielenga GÜ Unther R. Adolf Peter Herrlich Steven T. Pals 《Cell communication & adhesion》1994,2(3):195-200
Recently, splice variants of CD44 have been described that confer metastatic potential to non-metastasizing rat pancreatic carcinoma and sarcoma cell lines. Using antibodies against variant CD44 (CD44v) sequences, we have examined the expression of variant CD44 glycoproteins on human lymphoid cells and tissues and in colorectal neoplasia. Lymphohematopoietic cells express low levels of CD44v glycoproteins. During the process of lymphocyte activation in vitro and in vivo, expression of CD44v glycoproteins is transiently upregulated. The reaction pattern of various antibodies indicates that these CD44 variants contain the domain encoded by exon v6, which is part of the variant that confers metastatic capability. In human colorectal neoplasia we observed overexpression of CD44 splice variants in all invasive carcinomas. Already at early stages of colorectal tumor progression exon v5 epitopes were overexpressed. Tumor progression was strongly related to expression of CD44 isoforms containing exon v6 encoded domains. The findings establish CD44 variants as tumor progression markers in colorectal cancer. 相似文献
3.
Vladimir Vartanian Jocelyn F. Krey Paroma Chatterjee Allison Curtis Makayla Six Sean P. M. Rice Sherri M. Jones Harini Sampath Charles N. Allen Renee C. Ryals R. Stephen Lloyd Peter G. Barr-Gillespie 《Genes, Brain & Behavior》2023,22(4):e12849
Relationships between novel phenotypic behaviors and specific genetic alterations are often discovered using target-specific, directed mutagenesis or phenotypic selection following chemical mutagenesis. An alternative approach is to exploit deficiencies in DNA repair pathways that maintain genetic integrity in response to spontaneously induced damage. Mice deficient in the DNA glycosylase NEIL1 show elevated spontaneous mutations, which arise from translesion DNA synthesis past oxidatively induced base damage. Several litters of Neil1 knockout mice included animals that were distinguished by their backwards-walking behavior in open-field environments, while maintaining frantic forward movements in their home cage environment. Other phenotypic manifestations included swim test failures, head tilting and circling. Mapping of the mutation that conferred these behaviors showed the introduction of a stop codon at amino acid 4 of the Ush1g gene. Ush1gbw/bw null mice displayed auditory and vestibular defects that are commonly seen with mutations affecting inner-ear hair-cell function, including a complete lack of auditory brainstem responses and vestibular-evoked potentials. As in other Usher syndrome type I mutant mouse lines, hair cell phenotypes included disorganized and split hair bundles, as well as altered distribution of proteins for stereocilia that localize to the tips of row 1 or row 2. Disruption to the bundle and kinocilium displacement suggested that USH1G is essential for forming the hair cell's kinocilial links. Consistent with other Usher type 1 models, Ush1gbw/bw mice had no substantial retinal degeneration compared with Ush1gbw/+ controls. In contrast to previously described Ush1g alleles, this new allele provides the first knockout model for this gene. 相似文献
4.
Biomechanics of chelipeds in some decapod crustaceans 总被引:2,自引:0,他引:2
The major chelipeds of five species of decapod crustaceans were studied with reference to lever system mechanical advantage, pattern of occlusive geometry, and force/pressure developed during cheliped closure by intact animals. Every cheliped type was found to possess a linear array of two to four distinctive regions of occlusion. The factors responsible for the differences in occlusive design are discussed. It is suggested that crustacean major chelipeds must be regarded as regionally-specialized, multifunctional appendages. 相似文献
5.
Karuppanan Muthusamy Kathir Li Gao Dakshinamurthy Rajalingam Sherri Brixey Dan Davis Igor Prudovsky 《生物化学与生物物理学报:生物膜》2010,1798(2):297-302
Human fibroblast growth factor (hFGF-1) is a ∼ 17 kDa heparin binding cytokine. It lacks the conventional hydrophobic N-terminal signal sequence and is secreted through non-classical secretion routes. Under stress, hFGF-1 is released as a multiprotein complex consisting of hFGF-1, S100A13 (a calcium binding protein), and p40 synaptotagmin (Syt1). Copper (Cu2+) is shown to be required for the formation of the multiprotein hFGF-1 release complex (Landriscina et al. ,2001; Di Serio et al., 2008). Syt1, containing the lipid binding C2B domain, is believed to play an important role in the eventual export of the hFGF-1 across the lipid bilayer. In this study, we characterize Cu2+ and lipid interactions of the C2B domain of Syt1 using multidimensional NMR spectroscopy. The results highlight how Cu2+ appears to stabilize the protein bound to pS vesicles. Cu2+ and lipid binding interface mapped using 2D 1H-15N heteronuclear single quantum coherence experiments reveal that residues in β-strand I contributes to the unique Cu2+ binding site in the C2B domain. In the absence of metal ions, residues located in Loop II and β-strand IV contribute to binding to unilamelar pS vesicles. In the presence of Cu2+, additional residues located in Loops I and III appear to stabilize the protein-lipid interactions. The results of this study provide valuable information towards understanding the molecular mechanism of the Cu2+-induced non-classical secretion of hFGF-1. 相似文献
6.
7.
Asadur Tchekmedyian Christopher I. Amos Sherri J. Bale Dakai Zhu Stefan Arold Joaquin Berrueta Natalie Nabon Thomas McGarrity 《PloS one》2013,8(11)
Background
Peutz-Jeghers syndrome (PJS) is characterized by intestinal polyposis, mucocutaneous pigmentation and an increased cancer risk, usually caused by mutations of the STK11 gene. This study collected epidemiological, clinical and genetic data from all Uruguayan PJS patients.Methods
Clinical data were obtained from public and private medical centers and updated annually. Sequencing of the STK11 gene in one member of each family was performed.Results and discussion
25 cases in 11 unrelated families were registered (15 males, 10 females). The average age of diagnosis and death was 18 and 41 years respectively. All patients had characteristic PJS pigmentation and gastrointestinal polyps. 72% required urgent surgery due to intestinal obstruction. 3 families had multiple cases of seizure disorder, representing 20% of cases. 28% developed cancer and two patients had more than one cancer. An STK11 mutation was found in 8 of the 9 families analyzed. A unique M136K missense mutation was noted in one family. Comparing annual live births and PJS birth records from 1970 to 2009 yielded an incidence of 1 in 155,000.Conclusion
The Uruguayan Registry for Peutz-Jeghers patients showed a high chance of emergent surgery, epilepsy, cancer and shortened life expectancy. The M136K missense mutation is a newly reported STK 11 mutation. 相似文献8.
Gizem Kalay Joel Atallah Noemie C. Sierra Austin M. Tang Amanda E. Crofton Mohan K. Murugesan Sherri Wykoff-Clary Susan E. Lott 《Evolution; international journal of organic evolution》2020,74(7):1409-1422
Many developmental traits that are critical to the survival of the organism are also robust. These robust traits are resistant to phenotypic change in the face of variation. This presents a challenge to evolution. In this article, we asked whether and how a well-established robust trait, Drosophila segment patterning, changed over the evolutionary history of the genus. We compared segment position scaled to body length at the first-instar larval stage among 12 Drosophila species. We found that relative segment position has changed many times across the phylogeny. Changes were frequent, but primarily small in magnitude. Phylogenetic analysis demonstrated that rates of change in segment position are variable along the Drosophila phylogenetic tree, and that these changes can occur in short evolutionary timescales. Correlation between position shifts of segments decreased as the distance between two segments increased, suggesting local control of segment position. The posterior-most abdominal segment showed the highest magnitude of change on average, had the highest rate of evolution between species, and appeared to be evolving more independently as compared to the rest of the segments. This segment was exceptionally elongated in the cactophilic species in our dataset, raising questions as to whether this change may be adaptive. 相似文献
9.
Short-Term Effects of Traditional and Alternative Community Interventions to Address Food Insecurity