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981.
Jasmonates (JAs) are the well characterized fatty acid-derived cyclopentanone signals involved in the plant response to biotic and abiotic stresses. JAs have been shown to regulate many aspects of plant metabolism, including glucosinolate biosynthesis. Glucosinolates are natural plant products that function in defense against herbivores and pathogens. In this study, we applied a proteomic approach to gain insight into the physiological processes, including glucosinolate metabolism, in response to methyl jasmonate (MeJA). We identified 194 differentially expressed protein spots that contained proteins that participated in a wide range of physiological processes. Functional classification analysis showed that photosynthesis and carbohydrate anabolism were repressed after MeJA treatment, while carbohydrate catabolism was up-regulated. Additionally, proteins related to the JA biosynthesis pathway, stress and defense, and secondary metabolism were up-regulated. Among the differentially expressed proteins, many were involved in oxidative tolerance. The results indicate that MeJA elicited a defense response at the proteome level through a mechanism of redirecting growth-related metabolism to defense-related metabolism. 相似文献
982.
Although the wheat hybrids have often shown higher grain yields, the physiological basis of the higher yields remains unknown. Previous studies suggest that tolerance to photoinhibition in the hybrid may be one of the physiological bases (Yang et al., 2006, Plant Sci 171:389-97). The objective of this study was to further investigate the possible mechanism responsible for tolerance to photoinhibition in the hybrid. Photosystem II (PSII) photochemistry, the xanthophyll cycle, and antioxidative defense system were compared between the hybrid and its parents subjected to high light stress (1500 μmol m−2 s−1). The analyses of oxygen-evolving activity, chlorophyll fluorescence, and protein blotting demonstrated that the higher tolerance in the hybrid than in its parents was associated with its higher tolerance of PSII to photoinhibition. High light induced an increase in non-photochemical quenching, and this increase was greater in the hybrid than in its parents. There were no differences in the pool size of the xanthophyll cycle between the hybrid and its parents. The content of violaxanthin decreased significantly, whereas the content of zeaxanthin + antherxanthin increased considerably during high light treatments. However, the decrease in violaxanthin content and the increase in zeaxanthin + antherxanthin content were greater in the hybrid than in its parents. High light resulted in a significant accumulation of H2O2, O2− and catalytic Fe, and this accumulation was less in the hybrid than in its parents. High light induced a significant increase in the activities of superoxide dismutase, catalase, ascorbate peroxidase, glutathione reductase, dehydroascorbate reductase, and monodehydroascorbate reductase, and these increases were greater in the hybrid than its parents. These results suggest that the higher tolerance to photoinhibition in the hybrid may be associated with its higher capacity for antioxidative defense metabolism and the xanthophyll cycle. 相似文献
983.
With-No-Lysine [K] 4 (WNK4) kinase regulates the surface expression of various ion transporters. Not only ion transporters but G-protein coupled receptors (GPCR) can function properly when their expression level is appropriate at the plasma membrane. In this study, we examined the role of WNK4 kinase in the regulation of muscarinic receptor 3 (M3R) using physiological and biochemical experiments. Measurement of the pilocarpine-responsive [Ca2+]i change demonstrated that WNK4 kinase decreased the activity of M3R through its reduced surface expression. Kinase domain of WNK4 bound with the third intracellular region of M3R whereas its negative regulation was independent on the kinase activity. Comparable to wild-type WNK4, kinase-inactive WNK4D318A mutant also reduced the surface expression of M3R, whereas the kinase domain of WNK41-441 failed to reduce the surface expression of M3R. In accordance with surface biotinylation experiments, non-permeable immunostaining of M3R also showed that M3R surface expression is independent on the kinase activity of WNK4. Interestingly, comparison of the half life of total and surface M3R revealed that only the half life of total M3R, but not surface M3R was decreased by WNK4 kinase. Nevertheless, the rate of decrease in surface M3R always exceeded that of total M3R. Taken together, these results suggest that WNK4 kinase negatively regulates the anterograde trafficking of M3R through kinase-independent mechanism. 相似文献
984.
Held on November 19, 2012 in Saint-Cyr-sur-Loire, France, the symposium “From Bretonneau to therapeutic antibodies, from specificity to specific remedies” focused on the historical development of antibodies as therapeutics, with an emphasis on the seminal work of the French physician Pierre-Fidèle Bretonneau (1778–1862). The morning session was devoted to discussion of the evolution of the concept of specificity in medicine, which started with an epistemological definition. The contributions of Bretonneau to the emergence of the concept of specificity, notably with his studies on diphtheria, and the subsequent development of antidiphtheric serotherapy in Europe during the period 1894–1898 were then presented in detail. The afternoon session began with a presentation on the role of French physiologists during the years 1860–1890 in establishing the basic concepts of specific immunity and the principles of serotherapy. The history of antivenom serotherapy, particularly its discovery by Césaire Phisalix, and the development of antilymphocyte globulins as successful transplantation drugs were then discussed. The symposium ended with the inauguration of a stele representing Bretonneau, who lived in Saint-Cyr-sur-Loire and died 150 y ago. 相似文献
985.
摘要 目的:比较超声引导下18针与20针穿刺活检对甲状腺结节的诊断效果。方法:选取我院超声科2018.8.6-2020.9.30共收治的167例甲状腺结节患者作为研究对象,将患者分为18针穿刺组(n=86)和20针穿刺组(n=81),分别对两组患者应用超声引导下18针和20针穿刺活检,比较不确定结果的发生率,包括非诊断性或异型性/滤泡性病变的未确定显著性,恶性肿瘤的诊断性能在最终诊断的结节中进行评估。比较两组并发症发生率及超声引导下的核心针穿刺活检标本产率。结果:对比20针穿刺组和18针穿刺组患者的临床特征发现,两组患者性别、年龄、结节大小、结节形状、方位、回声强度、表现和钙化情况对比无明显差异(P<0.05);在20针穿刺组中43个结节和18针穿刺组中46个结节最终确诊。恶性结节的比例在两组之间没有显著差异。在最终诊断分析中,20针穿刺组有38个结节,18针穿刺组中有40个结节。在20针穿刺组,38个结节包括6个非诊断结果、18个不典型/滤泡性病变(未确定显著性)和14个滤泡性肿瘤。在18针穿刺组中,40个结节包括1个非诊断结果,22个不典型/滤泡性病变未确定的显著性,17个滤泡性肿瘤;18针穿刺组的未确诊率(包括非诊断结果和未发现显著性的异型性/滤泡性病变)较低(29.1 % vs 37.0 %),尽管这一差异在统计学上没有显著性(P>0.05)。然而,18针穿刺组的非诊断性结果发生率(1.2 % vs 8.6 %;P<0.05)显著低于20针穿刺组。两组的不典型/滤泡性病变的发生率(27.8 % vs 28.4 %)相似。20针穿刺组的CNB显示出更高的敏感性(75.0 % vs 66.7 %),更高的阴性预测值(NPV;83.9 % vs 75.9 %)和更高的准确率(78.3 % vs 74.4 %),虽然结果没有达到统计显著性。两组的特异性(81.8 % vs 80.8 %)和阳性预测值(PPV;两者均为100 %)相似;18针穿刺组和20针穿刺组患者的并发症发生率对比无明显差异(P>0.05)。结论:18针芯针活检对甲状腺结节的诊断较20针更有效,且不增加并发症情况,安全性好,值得临床应用推广。 相似文献
986.
Ginsenosides (20S)-Rg3 and (20R)-Rg3 are famous rare ginsenosides from red ginseng, and their configurations in C-20 are different. This study aimed to investigate the protective mechanism of ginsenosides (20S)-Rg3 and (20R)-Rg3 on H2O2-induced H9C2 cells and compare their activity. The results showed that the ginsenosides (20S)-Rg3 and (20R)-Rg3 could increase the cell activity and the levels of GSH-Px, SOD and CAT, and decrease activities of LDH, MDA and ROS. Further studies showed that ginsenosides (20S)-Rg3 and (20R)-Rg3 could prevent oxidative stress injury of H9C2 cells by H2O2 through the Keap-1/Nrf2/HO-1 pathway. But the ML385 counteracts these effects. Interestingly, among these results, ginsenoside (20R)-Rg3 was superior to (20S)-Rg3, indicating that ginsenoside (20R)-Rg3 have a stronger effect of antioxidative stress. This study reflected that ginsenoside (20R)-Rg3 could be used as a potential Nrf2 activator and a safe effective Chinese herbal monomer in the treatment of cardiovascular disease. 相似文献
987.
Gabriela Morilha Zanarotti Juliana A. Cândido‐Silva Jorge Cury de Almeida 《Genesis (New York, N.Y. : 2000)》2009,47(12):847-857
Recently we have shown that BhSGAMP‐1 is a developmentally regulated reiterated gene that encodes an antimicrobial peptide (AMP) and is expressed exclusively in the salivary glands, at the end of the larval stage. We show, for the first time, that a gene for an AMP is directly activated by 20‐OH ecdysone. This control probably involves the participation of short‐lived repressor(s). We also found that the promoter of BhSGAMP‐1 is not equipped with elements that respond to infection, provoked by the injection of microorganisms, in the salivary glands or in the fat body. We produced polyclonal antibodies against the synthetic peptide and found that the BhSGAMP‐1 peptide is secreted in the saliva. The BhSGAMP‐1 gene was also activated during the third larval molt. These facts confirm our hypothesis that this preventive system of defense was selected to produce an environment free of harmful microorganisms in the insect's immediate vicinity, during molts. genesis 47:847–857, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
988.
In the present study, we investigate effect of amylin on the insulin sensitivity of rat skeletal muscle extensor digitorum longus (EDL) using in vitro intact muscle incubation in combination with metabolic radioactive labeling. The molecular basis of the amylin action was further examined using proteomic analysis. In particular, proteins of interest were characterized using an integrated microcharacterization procedure that involved in-gel trypsin digestion, organic solvent extraction, high performance liquid chromatography separation, microsequencing and microsequence analysis. We found that amylin significantly decreased the insulin-stimulated glucose incorporation into glycogen (p < 0.01) and produced a protein spot of approximately 20 ku in size. This amylin responsive protein (hereby designated as amylin responsive protein 1, APR1) was identified to be protein p20. Moreover, ARP1 spots on gels were found to consistently produce a corresponding radioactive spot on X-ray films in 32Pi but not in 35S-methionine labeling experiments. In conclusion, our results showed that in vitro amylin concomitantly evoked the production of ARP1 and caused insulin resistance in EDL muscle. It is suggested that protein p20 may be involved in amylin signal transduction and the appearance of ARP1 may be a step in a molecular pathway leading to the development of insulin resistance. ARP1 might therefore be a useful molecular marker for amylin action, insulin resistance and Type 2 diabetes. 相似文献
989.
990.
Solomon BD Pineda-Alvarez DE Hadley DW Keaton AA Agochukwu NB Raam MS Carlson-Donohoe HE Kamat A Chandrasekharappa SC 《Birth defects research. Part A, Clinical and molecular teratology》2011,91(9):862-865