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921.
On-line soft sensing in upstream bioprocessing   总被引:1,自引:0,他引:1  
This review provides an overview and a critical discussion of novel possibilities of applying soft sensors for on-line monitoring and control of industrial bioprocesses. Focus is on bio-product formation in the upstream process but also the integration with other parts of the process is addressed. The term soft sensor is used for the combination of analytical hardware data (from sensors, analytical devices, instruments and actuators) with mathematical models that create new real-time information about the process. In particular, the review assesses these possibilities from an industrial perspective, including sensor performance, information value and production economy. The capabilities of existing analytical on-line techniques are scrutinized in view of their usefulness in soft sensor setups and in relation to typical needs in bioprocessing in general. The review concludes with specific recommendations for further development of soft sensors for the monitoring and control of upstream bioprocessing.  相似文献   
922.
Cardiovascular diseases are a major cause of human death worldwide. Excessive proliferation of vascular smooth muscle cells contributes to the etiology of such diseases, including atherosclerosis, restenosis, and pulmonary hypertension. The control of vascular cell proliferation is complex and encompasses interactions of many regulatory molecules and signaling pathways. Herein, we recapitulated the importance of signaling cascades relevant for the regulation of vascular cell proliferation. Detailed understanding of the mechanism underlying this process is essential for the identification of new lead compounds (e.g., natural products) for vascular therapies.  相似文献   
923.
The phosphorylation state of pocket proteins during the cell cycle is determined at least in part by an equilibrium between inducible cyclin-dependent kinases (CDKs) and serine/threonine protein phosphatase 2A (PP2A). Two trimeric holoenzymes consisting of the core PP2A catalytic/scaffold dimer and either the B55α or PR70 regulatory subunit have been implicated in the activation of p107/p130 and pRB, respectively. While the phosphorylation state of p107 is very sensitive to forced changes of B55α levels in human cell lines, regulation of p107 in response to physiological modulation of PP2A/B55α has not been elucidated. Here we show that fibroblast growth factor 1 (FGF1), which induces maturation and cell cycle exit in chondrocytes, triggers rapid accumulation of p107-PP2A/B55α complexes coinciding with p107 dephosphorylation. Reciprocal solution-based mass spectrometric analysis identified the PP2A/B55α complex as a major component in p107 complexes, which also contain E2F/DPs, DREAM subunits, and/or cyclin/CDK complexes. Of note, p107 is one of the preferred partners of B55α, which also associates with pRB in RCS cells. FGF1-induced dephosphorylation of p107 results in its rapid accumulation in the nucleus and formation of larger complexes containing p107 and enhances its interaction with E2F4 and other p107 partners. Consistent with a key role of B55α in the rapid activation of p107 in chondrocytes, limited ectopic expression of B55α results in marked dephosphorylation of p107 while B55α knockdown results in hyperphosphorylation. More importantly, knockdown of B55α dramatically delays FGF1-induced dephosphorylation of p107 and slows down cell cycle exit. Moreover, dephosphorylation of p107 in response to FGF1 treatment results in early recruitment of p107 to the MYC promoter, an FGF1/E2F-regulated gene. Our results suggest a model in which FGF1 mediates rapid dephosphorylation and activation of p107 independently of the CDK activities that maintain p130 and pRB hyperphosphorylation for several hours after p107 dephosphorylation in maturing chondrocytes.  相似文献   
924.
Salt stress- and salicylic acid (SA)-induced cell death can be activated by various signaling pathways including ethylene (ET) signaling in intact tomato plants. In tomato suspension cultures, a treatment with 250 mM NaCl increased the production of reactive oxygen species (ROS), nitric oxide (NO), and ET. The 10?3 M SA-induced cell death was also accompanied by ROS and NO production, but ET emanation, the most characteristic difference between the two cell death programs, did not change. ET synthesis was enhanced by addition of ET precursor 1-aminocyclopropane-1-carboxylic acid, which, after 2 h, increased the ROS production in the case of both stressors and accelerated cell death under salt stress. However, it did not change the viability and NO levels in SA-treated samples. The effect of ET induced by salt stress could be blocked with silver thiosulfate (STS), an inhibitor of ET action. STS reduced the death of cells which is in accordance with the decrease in ROS production of cells exposed to high salinity. Unexpectedly, application of STS together with SA resulted in increasing ROS and reduced NO accumulation which led to a faster cell death. NaCl- and SA-induced cell death was blocked by Ca2+ chelator EGTA and calmodulin inhibitor W-7, or with the inhibitors of ROS. The inhibitor of MAPKs, PD98059, and the cysteine protease inhibitor E-64 reduced cell death in both cases. These results show that NaCl induces cell death mainly by ET-induced ROS production, but ROS generated by SA was not controlled by ET in tomato cell suspension.  相似文献   
925.
926.
Sperm cryopreservation is the most efficient method for storing boar sperm samples for a long time. However, one of the inconveniences of this method is the large variation between and within boars in the cryopreservation success of their sperm. The aim of the present work was thus to find reliable and useful predictive biomarkers of the good and poor capacity to withstand the freeze-thawing process in boar ejaculates. To find these biomarkers, the amount of proteins present in the total proteome in sperm cells were compared between good freezability ejaculates (GFE) and poor freezability ejaculates (PFE) using the two-dimensional difference gel electrophoresis technique. Samples were classified as GFE and PFE using progressive motility and viability of the sperm at 30 and 240 minutes after thawing, and the proteomes from each group, before starting cryopreservation protocols, were compared. Because two proteins, acrosin binding protein (ACRBP) and triosephosphate isomerase (TPI), presented the highest significant differences between GFE and PFE groups in two-dimensional difference gel electrophoresis assessment, Western blot analyses for ACRBP and TPI were also performed for validation. ACRBP normalized content was significantly lower in PFE than in GFE (P < 0.05), whereas the TPI amounts were significantly lower in GFE (P < 0.05) than in PFE. The association of ACRBP and TPI with postthaw sperm viability and motility was confirmed using Pearson's linear correlation. In conclusion, ACRBP and TPI can be used as markers of boar sperm freezability before starting the cryopreservation procedure, thereby avoiding unnecessary costs involved in this practice.  相似文献   
927.
Drug abuse-induced neurodegeneration can be triggered by elevated production of reactive oxygen species (ROS). Involvement of oxidative stress in acute amphetamine (AMPH)-mediated dopamine (DA) release, however, has not been completely understood yet. In order to elucidate the dopaminergic response of PC12 cells to a single dose of 10 μM AMPH, ROS production was measured as related to the extracellular DA level. Due to the spontaneous oxidation of peroxide-sensitive fluorophore 2′,7′-dichlorofluorescin diacetate (DCFH-DA) to 2′,7′-dichlorofluorescein (DCF), the increase in fluorescence could not be unambiguously attributed to AMPH-triggered ROS production. Based on Amplex Red fluorescence, no ROS production was detected after acute AMPH application. Our data strongly suggest that ROS development was not the main triggering factor for immediate DA release after acute AMPH treatment. On the other hand, AMPH-induced elevation of DA levels in rat brain striatal slices was quenched by the water soluble antioxidant, N-acetylcysteine (NAC) at 10 mM. In this study, we also investigated the contribution of protein phosphatases to the AMPH-induced rat brain striatal dopaminergic response. The experimental protocol, double AMPH challenge was applied for screening the effect of NAC and cantharidin on AMPH-mediated DA release. Here we show that AMPH-mediated DA release increased nearly twofold in striatal rat brain slices pretreated for 30 min with 1000 μM cantharidin, a selective PP1 and PP2A inhibitor. These findings prove the lack of ROS inhibitory action on protein phosphatase activity in acute AMPH-mediated DA efflux.  相似文献   
928.
Cultivated buckwheat, such as common (Fagopyrum esculentum Moench.) and tartary (Fagopyrum tataricum (L.) Gaertn.) buckwheat, is one of the most versatile crops for forage and food and has several benefits for human health. Interspecific hybridization between Fagopyrum species is of great importance to improvement of buckwheat. Hybridization would allow the transfer of agronomical beneficial characteristics from wild Fagopyrum species, including self-pollination and increased fertility, frost tolerance, and higher content of beneficial compounds. However, conventional breeding methods are only partially applicable because of the self-incompatibility and incompatibility barriers between different species. Present review summarizes the morphology of self-incompatibility, the genetic and cellular basis of incompatibility between different Fagopyrum species. In many interspecific crosses hybrid embryos are aborted after successful pollination due to post-zygotic incompatibility. The use of in vitro embryo rescue after interspecific hybridization has been successful in circumventing breeding barriers between Fagopyrum species. Methods applied successfully for the construction of interspecific hybrids are discussed in detail.  相似文献   
929.
The majority of lung cancers (LC) belong to the non-small cell lung carcinoma (NSCLC) type. The two main NSCLC sub-types, namely adenocarcinoma (AC) and squamous cell carcinoma (SCC), respond differently to therapy. Whereas the link between cigarette smoke and lung cancer risk is well established, the relevance of non-canonical Wnt pathway up-regulation detected in SCC remains poorly understood. The present study was undertaken to investigate further the molecular events in canonical and non-canonical Wnt signalling during SCC development. A total of 20 SCC and AC samples with matched non-cancerous controls were obtained after surgery. TaqMan array analysis confirmed up-regulation of non-canonical Wnt5a and Wnt11 and identified down-regulation of canonical Wnt signalling in SCC samples. The molecular changes were tested in primary small airway epithelial cells (SAEC) and various lung cancer cell lines (e.g. A549, H157, etc). Our studies identified Wnt11 and Wnt5a as regulators of cadherin expression and potentiated relocation of β-catenin to the nucleus as an important step in decreased cellular adhesion. The presented data identifies additional details in the regulation of SCC that can aid identification of therapeutic drug targets in the future.  相似文献   
930.
Moldvay J 《Magyar onkologia》2007,51(3):191-196
Lung cancer is the leading cause of cancer death worldwide, and it is responsible for 20-25% of all cancer deaths. In Hungary, more than 4,000 lung cancer patients receive chemotherapy every year, and of them 3,000 suffer from non-small cell lung cancer. Despite the rapid development in antitumor treatment options, the response rates of chemotherapies in non-small cell lung cancer still remain between 15-35%. Recently, EGFR tyrosine kinase inhibitor therapy has been introduced with a response rate of 15% when used in unselected patients. However, this ratio may increase up to 70% when only patients with tumors containing EGFR mutation are treated. Therefore, results of translational research that could help pulmonologists and oncologists to apply tailored therapy in lung cancer patients are of great importance. The purpose of our work was to establish a model in order to study the relevance of immunohistochemical and molecular biological analyses of tumor specimens in treatment and patient selection, and to investigate their cost-sparing effects. We concluded that the most cost-effective type of patient selection could be achieved with EGFR mutation status analysis of the tumor tissue. Our results may help to determine the most cost-effective way of patient selection in case of non-small cell lung cancer patients requiring second line therapy; moreover, they might serve as a basis for further economic analyses.  相似文献   
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