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71.
The β(1,2)-xylose- and/or α(1,3)-fucose-containing cross-reactive carbohydrate determinants (CCDs) are present in various plant and insect N-glycans, and have been attracted as potential antigens in IgE-mediated allergies and immunologically undesired post-translational products on some recombinant therapeutic proteins. By using ELISA and immunoblotting, CCDs-specific IgG and IgE antibodies from some, but not all, of mice and humans were found to fully retain their binding activity after a typical periodate-treatment to CCDs, which did cause the CCDs’ antigenic activity to those from the other mice and rabbits to disappear almost completely. Furthermore, the mouse IgE recognizing the periodate-resistant CCDs induced the CCDs/IgE-dependent degranulation of rat basophilic RBL-2H3 cells. These findings indicate that in some cases CCDs include those dependent of the core trisaccharide more strongly than the terminal xylose and fucose, which might have been screened out in the CCDs analyses based on the loss of antibody-binding by the periodate-treatment.  相似文献   
72.
73.

Background

No drugs have been approved for the treatment of patients with pulmonary hypertension (PH) secondary to idiopathic pulmonary fibrosis (IPF), particularly those with idiopathic honeycomb lung. This study was conducted to investigate the long-term efficacy and safety of bosentan for PH based on changes in prognosis and respiratory failure.

Methods

IPF patients with borderline or less severe PH and completely organized honeycomb lung were randomized (1:1) to bosentan or no treatment for PH for 2 years and assessed at baseline and every 6 months for respiratory failure, activities of daily living (ADL), lung and heart functions by right cardiac catheterization, and other parameters. An interim analysis was performed, however, following detection of a significant survival benefit favoring bosentan therapy.

Results

Significant differences were noted for the bosentan-treated (n?=?12) vs. untreated (n?=?12) groups in hospital-free survival (603.44?±?50.074 days vs. 358.87?±?68.65 days; hazard ratio [HR], 0.19; P?=?0.017) and overall survival (671 days vs. 433.78?±?66.98 days; HR, 0.10; P?=?0.0082). Again, significant improvements were noted for the bosentan-treated group from baseline to month 6 or 12 in several indices in ADL, pulmonary circulation, and %DLCO. Without requiring O2 inhalation, bosentan was associated with no increase but a trend toward a decrease in adverse events and an improvement in respiratory status.

Conclusions

Bosentan tended to improve prognosis and ADL without worsening respiratory failure in IPF patients with borderline or less severe PH and completely organized honeycomb lung alone.

Trial registration

This study was registered on December 18, 2010 with UMIN-CTR Clinical Trial as UMIN000004749 to investigate the long-term influence of bosentan on cardiac function, as well as its cardioprotective efficacy and safety, in patients with pulmonary hypertension secondary to concurrent COPD and IPF, respectively.
  相似文献   
74.
Habitat, diet and leaf chemistry are compared between Japanese and Barbary macaques to reveal the similarities and differences in dietary adaptations of temperate primates living at the eastern and western extremes of the genus Macaca. Tree species diversity and proportion of fleshy-fruited species are much higher in Japan than in North Africa. Both species spend considerable annual feeding time on leaves. Japanese macaques prefer fruits and seeds over leaves, and Barbary macaques prefer seeds. These characteristics are adaptive in temperate regions where fruit availability varies considerably with season, since animals can survive during the lean period by relying on leaf and other vegetative foods. The two species are different with respect to the higher consumption of herbs by Barbary macaques, and the leaves consumed contain high condensed and hydrolysable tannin for Barbary but not for Japanese macaques. Barbary macaques supplement less diverse tree foods with herbs. Because of the low species diversity and high tannin content of the dominant tree species, Barbary macaques may have developed the capacity to cope with tannin. This supports the idea that digestion of leaves is indispensable to survive in temperate regions where fruit and seed foods are not available for a prolonged period during each year.  相似文献   
75.
The Madagascar Paradise Flycatcher Terpsiphone mutata and Common Newtonia Newtonia brunneicauda frequently form two-species flocks in the deciduous dry forest of western Madagascar. In T. mutata , some males have long tails, while other males and females have short tails. When foraging in mixed flocks, each type of bird captured prey more rapidly than otherwise, but the degree of increase in feeding rate was smaller in long-tailed males. When in mixed flocks, all T. mutata caught prey on leaves in the canopy where N. brunneicauda foraged. Long-tailed males changed feeding habits from sallying when not in mixed flocks, whereas short-tailed birds showed no change of feeding habit. The elongated tails of long-tailed males may have made their foraging less efficient owing to decreased agility in the canopy. N. brunneicauda is monomorphic and often formed groups of three to five individuals. In monospecific flocks, subordinates fed at low rates on branches owing to frequent hostile encounters. When foraging in mixed flocks, however, subordinates foraged among leaves, and their feeding rates increased because the frequency of intraspecific interference decreased greatly. Dominants did not show any difference in feeding pattern with social situation. Thus, heterospecific flocking was more advantageous for subordinates.  相似文献   
76.
Ornithoptera birdwing butterflies have blue, green, or orange iridescent scales in different species or subspecies. To understand the species‐ or subspecies‐dependent scale color differences, we performed comparative morphometric analyses of iridescent scales from three closely related taxa: O. priamus priamus (green), O. priamus urvillianus (blue), and O. croesus (orange). The three types of Ornithoptera wings exhibited reversible color changes to longer wavelengths with different kinetics upon immersion in methanol, suggesting that their color differences are at least partly based on differences in the size of air cavities made by nanostructures. Cover scales of all three color types were visually semi‐transparent glass scales that exhibited color when placed on a dark background. The dorsoventral differences in coloration were observed in single scales, suggesting the optical importance of scale surfaces. Scanning electron microscopy of cover scales in cross section revealed that all color types exhibited finely sculpted tapered ridges and thick, irregular basal multilayers containing tandemly clustered granular objects and air cavities. Scale thickness, ridge height, and multilayer thickness were significantly different among the three color types, and granular object size was significantly different between orange scales and blue and green scales. We conclude that each of the three taxa of Ornithoptera butterflies possesses unique quantitative size values on tapered ridges and irregular multilayers with granular objects and air cavities to express unique structural color. These species‐ or subspecies‐dependent structural colors might have evolved via quantitative shifts in these microarchitectural traits rather than via changes in the basic developmental or architectural plan for color expression.  相似文献   
77.
How do deer affect tree seedlings on a dwarf bamboo-dominated forest floor?   总被引:4,自引:0,他引:4  
A field experiment was conducted in Mt. Ôdaigahara, west-central Japan, to reveal the effects of two herbivores, Sika deer (Cervus nippon) and mice (Apodemus spp.), on the seedlings of five cohorts of three tree species, Abies homolepis, Fraxinus lanuginosa f. serrata and Fagus crenata. The forest floor of the study site was covered with dwarf bamboo, Sasa nipponica, which would also affect the seedlings. Eight combinations of three treatments were set: exclusion of deer, exclusion of mice and removal of dwarf bamboo. Deer were expected to affect the seedlings not only negatively by foraging but also positively by browsing dwarf bamboo that overshadows seedlings. The survival of these cohorts was analyzed by survival analysis and the differences in their survival between the treatments were investigated. The results of the experiment showed that: (1) exclusion of deer increased the aboveground biomass of dwarf bamboo and made it more difficult for seedlings to survive under the regenerated dwarf bamboo stand, and (2) deer negatively affected the seedlings, but they had positive, indirect effects in some cohorts by decreasing the aboveground biomass of dwarf bamboo. However, such effects were not detected in some cohorts which were affected excessively by deer or dwarf bamboo. No clear results on the effect of mice on seedlings were obtained. We conclude that a positive, indirect effect of deer on seedling survivorship would be observable when the magnitude of a positive, indirect effect caused by decreasing dwarf bamboo is larger than that of a negative, direct effect of deer.  相似文献   
78.
In attempting to clarify the roles of Dvl in the Wnt signaling pathway, we identified a novel protein which binds to the PDZ domain of Dvl and named it Idax (for inhibition of the Dvl and Axin complex). Idax and Axin competed with each other for the binding to Dvl. Immunocytochemical analyses showed that Idax was localized to the same place as Dvl in cells and that expression of Axin inhibited the colocalization of Dvl and Idax. Further, Wnt-induced accumulation of beta-catenin and activation of T-cell factor in mammalian cells were suppressed by expression of Idax. Expression of Idax in Xenopus embryos induced ventralization with a reduction in the expression of siamois, a Wnt-inducible gene. Idax inhibited Wnt- and Dvl- but not beta-catenin-induced axis duplication. It is known that Dvl is a positive regulator in the Wnt signaling pathway and that the PDZ domain is important for this activity. Therefore, these results suggest that Idax functions as a negative regulator of the Wnt signaling pathway by directly binding to the PDZ domain of Dvl.  相似文献   
79.
h-prune, which has been suggested to be involved in cell migration, was identified as a glycogen synthase kinase 3 (GSK-3)-binding protein. Treatment of cultured cells with GSK-3 inhibitors or small interfering RNA (siRNA) for GSK-3 and h-prune inhibited their motility. The kinase activity of GSK-3 was required for the interaction of GSK-3 with h-prune. h-prune was localized to focal adhesions, and the siRNA for GSK-3 or h-prune delayed the disassembly of paxillin. The tyrosine phosphorylation of focal adhesion kinase (FAK) and the activation of Rac were suppressed in GSK-3 or h-prune knocked-down cells. GSK-3 inhibitors suppressed the disassembly of paxillin and the activation of FAK and Rac. Furthermore, h-prune was highly expressed in colorectal and pancreatic cancers, and the positivity of the h-prune expression was correlated with tumor invasion. These results suggest that GSK-3 and h-prune cooperatively regulate the disassembly of focal adhesions to promote cell migration and that h-prune is useful as a marker for tumor aggressiveness.  相似文献   
80.
The products of the TSC1 (hamartin) and TCS2 (tuberin) tumor suppressor genes negatively regulate cell growth by inhibiting mTOR signaling. Recent research has led to the postulation that tuberin and/or hamartin are involved in tumor migration, presumably through Rho activation. Here we show that LEF-8 cells, which contain a Y1571 missense mutation in tuberin, express higher Rac1 activity than tuberin negative and positive cells. We also provide evidence of obvious lamellipodia formation in LEF-8 cells. Since the production of TSC2Y1571H cannot form a hetero-complex with hamartin, we further analyzed another mutant, TSC2R611Q, which also lacks the ability to form a complex with hamartin. Introducing both forms of mutated TSC2 into COS-1 cells increased Rac1 activity as well as cell motility. We also found these two mutants interacted with Rac1. We further demonstrated that the introduction of mutated TSC2 into COS-1 cells can generate higher reactive oxygen species (ROS). These results indicate that loss-of-function mutated tuberin can activate Rac1 and thereby increase ROS production.  相似文献   
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