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1.
We have shown in an initial animal study that omentum will adequately vascularize a skin flap and allow transfer of this tissue composite for use in surgical reconstruction of the breast. Based on this experimental procedure, a technique employing a two-stage operation has been developed and used in 21 female patients in reconstruction of the breast after radical mastectomy. In the first stage, the omentum, attached to one gastroepiploic artery and vein, is exteriorized to the subcutaneous tissue of the lower abdominal wall. In the second stage, the distal omentum, now vascularizing the overlying skin and soft tissue, is moved as a secondary island flap to the anterior chest wall to complete the breast reconstruction. In all but 1 of our 21 patients who have been followed for 1 to 8 years, reconstruction of large defects, including the chest wall, breast mound, and infraclavicular axillary fold depression, was performed without use of a prosthesis. In one patient, there was complete necrosis of the flap due to vascular impairment; there were three instances of delayed healing and a significant but partial loss of the flap in one patient. All complications were encountered in the first 10 patients of the series during the time the technique was being refined. 相似文献
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Many symbioses have costs and benefits to their hosts that vary with the environmental context, which itself may vary in space. The same symbiont may be a mutualist in one location and a parasite in another. Such spatially conditional mutualisms pose a dilemma for hosts, who might evolve (higher or lower) horizontal or vertical transmission to increase their chances of being infected only where the symbiont is beneficial. To determine how transmission in hosts might evolve, we modeled transmission evolution where the symbiont had a spatially conditional effect on either host lifespan or fecundity. We found that over ecological time, symbionts that affected lifespan but not fecundity led to high frequencies of infected hosts in areas where the symbiont was beneficial and low frequencies elsewhere. In response, hosts evolved increased horizontal transmission only when the symbiont affected lifespan. We also modeled transmission evolution in symbionts, which evolved high horizontal and vertical transmission, indicating a possible host–symbiont conflict over transmission mode. Our results suggest an eco‐evolutionary feedback where the component of host fitness affected by a conditionally mutualistic symbiont in turn determines its distribution in the population, and, through this, the transmission mode that evolves. 相似文献
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Garg R Juncadella IJ Ramamoorthi N Ashish Ananthanarayanan SK Thomas V Rincón M Krueger JK Fikrig E Yengo CM Anguita J 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(10):6579-6583
Salp15 is an Ixodes scapularis salivary protein that inhibits CD4+ T cell activation through the repression of TCR ligation-triggered calcium fluxes and IL-2 production. We show in this study that Salp15 binds specifically to the CD4 coreceptor on mammalian host T cells. Salp15 specifically associates through its C-terminal residues with the outermost two extracellular domains of CD4. Upon binding to CD4, Salp15 inhibits the subsequent TCR ligation-induced T cell signaling at the earliest steps including tyrosine phosphorylation of the Src kinase Lck, downstream effector proteins, and lipid raft reorganization. These results provide a molecular basis to understanding the immunosuppressive activity of Salp15 and its specificity for CD4+ T cells. 相似文献
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Zeynep Nagehan Yuruk Yildirim Sebahat Usta Akgul Harika Alpay Bagdagul Aksu Fatma Savran Oguz Aysel Kiyak Nurver Akinci Sevgi Yavuz Gul Ozcelik Asuman Gedikbasi Ibrahim Gokce Nese Ozkayin Nurdan Yildiz Cemile Pehlivanoglu Nilufer Goknar Seha Saygili Sebahat Tulpar Nuran Kucuk Ilmay Bilge Mehmet Tasdemir Ayse Agbas Ahmet Dirican Sevinc Emre Ahmet Nayir Alev Yilmaz 《Cell stress & chaperones》2021,26(6):973
Various molecular and cellular processes are involved in renal fibrosis, such as oxidative stress, inflammation, endothelial cell injury, and apoptosis. Heat shock proteins (HSPs) are implicated in the progression of chronic kidney disease (CKD). Our aim was to evaluate changes in urine and serum HSP levels over time and their relationships with the clinical parameters of CKD in children. In total, 117 children with CKD and 56 healthy children were examined. The CKD group was followed up prospectively for 24 months. Serum and urine HSP27, HSP40, HSP47, HSP60, HSP70, HSP72, and HSP90 levels and serum anti-HSP60 and anti-HSP70 levels were measured by ELISA at baseline, 12 months, and 24 months. The urine levels of all HSPs and the serum levels of HSP40, HSP47, HSP60, HSP70, anti-HSP60, and anti-HSP70 were higher at baseline in the CKD group than in the control group. Over the months, serum HSP47 and HSP60 levels steadily decreased, whereas HSP90 and anti-HSP60 levels steadily increased. Urine HSP levels were elevated in children with CKD; however, with the exception of HSP90, they decreased over time. In conclusion, our study demonstrates that CKD progression is a complicated process that involves HSPs, but they do not predict CKD progression. The protective role of HSPs against CKD may weaken over time, and HSP90 may have a detrimental effect on the disease course.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12192-021-01239-9. 相似文献
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Karel Indrak Vaclav Brabec Jarmila Indrakova Ladislav Chrobak Adriana Sakalova Marie Jarosova Jaroslav Cermak You-jun Fei Ferdane Kutlar Yuan-chao Gu Erol Baysal Titus H. J. Huisman 《Human genetics》1992,88(4):399-404
Summary We have identified different -thalassemia mutations in 93 members of 34 families of Czech or Slovakian descent using gene amplification, hybridization with specific 32P-labeled oligonucleotide probes, sequencing of amplified DNA, and gene mapping. The GA mutation at IVS-I-1 was found in 18 families; other Mediterranean mutations were IVS-II-1 (GA), IVS-II-745 (CG), IVS-I-110 (GA), and codon 39 (CT); these were present in 9 additional families. The GT mutation at codon 121, known to cause Heinzbody -thalassemia, was present in 3 families, and the frameshift at codons 82/83 (-G), first described in the Azerbaijanian population, in 2 families. A newly discovered allele was a frameshift at codons 38/39 (-C). One -thalassemia allele was incompletely characterized. We observed in 2 families a TC mutation at position +96 UTR (untranslated region) relative to the termination codon; this mutation likely is a rare polymorphism, -Thalassemia was rare; only one person carried the -3.7 heterozygosity, and one other had a yet to be identified -thalassemia-1, while seven had the anti 3.7 triplication. 相似文献
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Heart-type fatty acid-binding protein (H-FABP) is a major fatty acid-binding factor in skeletal muscles. Genetic lack of H-FABP
severely impairs the esterification and oxidation of exogenous fatty acids in soleus muscles isolated from chow-fed mice (CHOW-solei)
and high fat diet-fed mice (HFD-solei), and prevents the HFD-induced accumulation of muscle triacylglycerols (TAGs). Here,
we examined the impact of H-FABP deficiency on the relationship between fatty acid utilization and glucose oxidation. Glucose
oxidation was measured in isolated soleus muscles in the presence or absence of 1 mM palmitate (simple protocol) or in the
absence of fatty acid after preincubation with 1 mM palmitate (complex protocol). With the simple protocol, the mutation slightly
reduced glucose oxidation in CHOW-muscles, but markedly increased it in HFD-muscles; unexpectedly, this pattern was not altered
by the addition of palmitate, which reduced glucose oxidation in both CHOW- and HFD-solei irrespective of the mutation. In
the complex protocol, the mutation first inhibited the synthesis and accumulation of TAGs and then their mobilization; with
this protocol, the mutation increased glucose oxidation in both CHOW- and HFD-solei. We conclude: (i) H-FABP mediates a non-acute
inhibition of muscle glucose oxidation by fatty acids, likely by enabling both the accumulation and mobilization of a critical
mass of muscle TAGs; (ii) H-FABP does not mediate the acute inhibitory effect of extracellular fatty acids on muscle glucose
oxidation; (iii) H-FABP affects muscle glucose oxidation in opposing ways, with inhibition prevailing at high muscle TAG contents. 相似文献
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Immunocompetent mice 129Sv (129) and C57BL/6 (B6) mice are similarly susceptible to Anaplasma phagocytophilum. We now show that 129 mice lacking interferon-gamma (IFN-gamma) develop more severe infection with A. phagocytophilum than IFN-gamma deficient B6 mice. These data demonstrate that there is an inherent increased susceptibility of 129 mice, compared with B6 mice, to A. phagocytophilum that can only be discerned in the absence of IFN-gamma. 相似文献
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