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应用α-32P-dCTP标记HPV-11及HPV-16DNA为探针,以Slotblot及Southernblot两种核酸杂交技术,检测了取自青岛及北京两个地区的37例喉鳞癌组织DNA中HPV-11及HPV-16DNA相关序列。结果表明,Slotblot杂交中,与HPV-11探针杂交阳性者占86%(32/37),与HPV-16探针杂交阳性者占81%(30/37)。在同一癌组织中,与两型探针同时呈现阳性者占81%(30/37)。Southernblot杂交中,与所用探针DNA的内切酶PstⅠ酶切图谱比较,有46%(13/28)与HPV-16DNA的酶切图谱相同,可定为HPV-16型。当用HPV-11探针时无一例出现与HPV-11相同的图谱。提示喉癌的发生与HPV-16有关。  相似文献   
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Aims Players can wager on multiple lines of modern slot machines. When they spin and fail to gain any credits, the machine goes into a state of relative quiet. By contrast, when they spin and win, these spins are accompanied by reinforcing sights and sounds. Such reinforcement also occurs when the amount won is less than the spin wager. We sought to show that these ‘losses disguised as wins’, or LDWs, would be as arousing as wins, and more arousing than regular losses. Measurement and participants We measured skin conductance response (SCR) amplitudes and heart‐rate changes following wins, LDWs and losses for 40 novices playing a multi‐line slot machine. Findings SCR amplitudes were similar for wins and LDWs—both were significantly larger than for regular losses. Conclusions For novice players, the reinforcing sights and sounds of the slot machine triggered arousal on wins, where the number of credits gained was greater than the spin wager, but also on ‘losses disguised as wins’ where the amount ‘won’ was less than the spin wager. Despite the fact that players lost money on these spins, these outcomes were more arousing than regular losses where no credits were gained. Although these findings involve novice players, the heightened arousal associated with these losses may have implications for the development of problem gambling, as arousal has been viewed as a key reinforcer in gambling behaviour.  相似文献   
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针对基本混合蛙跳算法的收敛速度慢、容易陷入局部最优的缺点,提出了一种基于细胞通信策略的改进算法,该算法通过修改更新策略,从而增加了种群的多样性,产生更多靠近优质解的个体。用典型测试函数对基本蛙跳算法和改进的蛙跳算法及其他算法进行对比实验,仿真结果表明改进的蛙跳算法能较大幅度提高收敛精度。将改进的蛙跳算法应用于碳纤维生产过程水浴牵伸控制系统的优化,仿真结果表明其具有较好的优化控制效果。  相似文献   
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The stability of the neuroleptic peptide des-enkephalin--endorphin (DEE; Org 5878) in the rectal lumen and the rectal bioavailability of DEE were investigated in conscious rats. Furthermore, the influence of peptidase inhibition, peptidase saturation, and absorption enhancement on DEE bio-availability were evaluated. Na2EDTA (0.25%, w/v) prolonged the degradation half-life of DEE in the ligated colon from 33 ± 7 to 93 ± 45 min. Without adjuvant, tritium-labeled DEE was absorbed from the rat rectum to a very low extent (0–4%). After administration of an excess of unlabeled DEE or with Na2EDTA, comparable results were obtained. The medium-chain glyceride preparation MGK markedly enhanced the rectal DEE bioavailability, up to 8–20%, which was further increased to 10–44% by coadministration of Na2EDTA. No substantial influence of varying the rectal delivery rate was observed. The results suggest that absorption enhancement and enzyme inhibition both are essential for effective increase of rectal peptide bioavailability.  相似文献   
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We have developed a sensitive new assay for the detection of uracil in DNA. The assay described here is an adaptation to the highly sensitive aldehydic slot blot (ASB) assay developed by Nakamura et al. (Nakamura et al. 1998: Cancer Res 58:222-225) in which aldehydic DNA lesions (ADLs) are detected through binding of a biotinylated aldehydic reactive probe to DNA. The uracil DNA glycosylase (UDG)-coupled ASB assay uses uracil-DNA glycosylase to generate an abasic site, which is subsequently detected by the ASB methodology. The ability to modify this technique for the detection of uracil has these advantages: small quantities of DNA are required (4 microg of DNA); the assay is adaptable to DNA from both cells and tissues; sensitivity is as good as that achieved by less accessible methodologies, like gas chromatography-mass spectroscopy (GC-MS); DNA strand breaks are not a confounding variable; preexisting aldehydic lesions are blocked through the use of methoxyamine; variation is very low (<3%); radioactive isotopes are not required; and the assay is easy to establish and involves only equipment and reagents that are inexpensive and readily available. This assay is conceivably adaptable to the detection of other DNA base lesions through the use of a variety of DNA glycosylases.  相似文献   
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Cognition has a severely limited capacity: Adult humans can retain only about four items "in mind". This limitation is fundamental to human brain function: Individual capacity is highly correlated with intelligence measures and capacity is reduced in neuropsychiatric diseases. Although human capacity limitations are well studied, their mechanisms have not been investigated at the single-neuron level. Simultaneous recordings from monkey parietal and frontal cortex revealed that visual capacity limitations occurred immediately upon stimulus encoding and in a bottom-up manner. Capacity limitations were found to reflect a dual model of working memory. The left and right halves of visual space had independent capacities and thus are discrete resources. However, within each hemifield, neural information about successfully remembered objects was reduced by adding further objects, indicating that resources are shared. Together, these results suggest visual capacity limitation is due to discrete, slot-like, resources, each containing limited pools of neural information that can be divided among objects.  相似文献   
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Bergstrand H, Lundquist B. Human basophil histamine release is differently affected by inhibitors of calmodulin, diacylglycerol kinase and peptidyl prolyl cis-trans isomerase in a secretagogue specific manner. To assess the role of calmodulin in human basophil histamine release, we triggered leukocytes with different secretagogues in the presence of putative inhibitors of calmodulin. Calcium ionophore-induced histamine release was reduced or blocked by calmidazolium, CGS 9343B, felodipine, metofenazate, and Ro 22–4839. H 186/86, a felodipine-related dihydropyridine derivative, blocked A23187-but not ionomycin-triggered histamine release, suggesting a difference in the mode of action of these ionophores. In contrast, leukocyte histamine release triggered by the purported protein kinase C (PKC) activator, l, 2-isopropylidene-3-decanoyl- sn -glycerol (IpOCOC9), was enhanced by calmidazolium, CGS 9349B and metofenazate but not affected by felodipine or Ro 22-4839, whereas the response triggered by 4β-phorbol 12-myristate 13-aeetate (PMA) was reduced by metofenazate and Ro 22-4839 but not consistently affected by calmidazolium, CGS 9343B or felodipine. The PMA-induced histamine release was enhanced by H 186/86. Anti-IgE- and Fmlp -induced responses were either unaffected or slightly enhanced by the examined calmodulin antagonists. In comparison with the calmodulin antagonists, R 59022, an inhibitor of diacylglycerol kinase, failed to reduce calcium ionophore-triggered histamine release, whereas FK506, an inhibitor of peptidyl prolyl cis-trans isomerase (PPI), reduced both anti-IgE- and ionophore-triggered responses. These results indicate that calmodulin constitutes an obligate link in signal transduction pathways leading to human leukocyte histamine release if the trigger is a calcium ionophore but not when responses are induced by anti-IgE, Fmlp or PMA; a calmodulin-dependent component may rather balance responses induced by IpOCOC9. We also conclude that most employed stimuli, including IpOCOC9, trigger human basophil histamine release through partly distinet pathways.  相似文献   
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