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961.
Primaquine-based ionic liquids, obtained by acid-base reaction between parent primaquine and cinnamic acids, were recently found as triple-stage antimalarial hits. These ionic compounds displayed significant activity against both liver- and blood-stage Plasmodium parasites, as well as against stage V P. falciparum parasites. Remarkably, blood-stage activity of the ionic liquids against both chloroquine-sensitive (3D7) and resistant (Dd2) P. falciparum strains was clearly superior to those of the respective covalent (amide) analogues and of parent primaquine. Having hypothesized that such behaviour might be ascribed to an enhanced ability of the ionic compounds to permeate into Plasmodium-infected erythrocytes, we have carried out a differential scanning calorimetry-based study of the interactions between the ionic liquids and membrane models. Results provide evidence, at the molecular level, that the primaquine-derived ionic liquids may contribute to an increased permeation of the parent drug into malaria-infected erythrocytes, which has relevant implications towards novel antimalarial approaches based on ionic liquids.  相似文献   
962.
The biological effects of electromagnetic pulse (EMP) on the brain have been focused on for years. It was reported that gelatinase played an important role in maintaining brain function through regulating permeability in the blood–brain barrier (BBB). To investigate the effects of EMP on gelatinase of BBB, an in vitro BBB model was established using primary cultured rat brain microvascular endothelial cells (BMVEC), astrocytes and half-contact culture of these cells in a transwell chamber. Cultured supernatant and cells were collected at different time points after exposure to EMP (peak intensity 400 kV/m, rise time 10 ns, pulse width 350 ns, 0.5 pps and 200 pulses). Protein levels of cellular gelatinase MMP-2 and MMP-9, and endogenous inhibitor TIMP-1 and TIMP-2 were detected by Western blot. The activity of gelatinase in culture supernatant was detected by gelatin zymography. It was found that compared with the sham-exposed group, the protein level of MMP-2 was significantly increased at 6 h (p < 0.05), and the protein level of its endogenous inhibitor TIMP-2 did not change after EMP exposure. In addition, the protein levels of MMP-9 and its endogenous inhibitor TIMP-1 did not change after EMP exposure. Gelatin zymography results showed that the activity of MMP-2 in the inner pool and the outer pool of the transwell chamber was significantly increased at 6 h after EMP exposure compared with that of the sham group. These results suggested that EMP exposure could affect the expression and activity of MMP-2 in the BBB model.  相似文献   
963.
The decrease in apparent relative viscosity that occurs when blood is made to flow through a tube whose diameter is less than about 0.3 mm is a well-known and documented phenomenon in physiology, known as the Fåhræus-Lindqvist effect. However, since the historical work of Fåhræus and Lindqvist (Amer. J. Physiol. 96(3): pp. 562–568, 1931), the underlying physical mechanism has remained enigmatic. A widely accepted qualitative explanation was provided by Haynes (Amer. J. Physiol. 198, pp. 1193–1200, 1960) according to which blood flows in microvessels with a core-annulus structure, where the erythrocytes concentrate within a central core surrounded by a plasma layer. Although sustained by observations, this conjecture lacks a rigorous deduction from the basic principles of continuum dynamics. Moreover, relations aimed to reproduce the blood apparent relative viscosity, extensively used in micro-circulation, are all empirical and not derived from the analysis of the fluid mechanical phenomena involved. In this paper, we apply the recent results illustrated in Guadagni and Farina (Int. J. Nonlinear Mech. 126, p. 103587, 2020), with the purpose of showing that Haynes’ conjecture, slightly corrected to make it more realistic, can be proved and can be used to reach a sound explanation of the Fåhræus-Lindqvist effect based on continuum mechanics. We propose a theoretical model for the blood apparent relative viscosity which is validated by matching not only the original experimental data reported by Fåhræus and Lindqvist (Amer. J. Physiol. 96(3), pp. 562–568, 1931), but also those provided by several subsequent authors.  相似文献   
964.
965.
目的 探讨性别和年龄因素对封闭群草原兔尾鼠正常血液生化指标的影响。方法 利用雅培(AEROSET)全自动血液生化测定仪对雄性组、雌性组、1月龄 2月龄组和 2 4月龄组封闭群草原兔尾鼠的 2 3项血液正常生化指标进行了测定。结果 两年龄组各指标间以及两性别组各指标间均无统计学差异。结论 本实验中封闭群草原兔尾鼠的性别因素和年龄 (1月龄 - 2月龄年龄段和 2 4月龄年龄段 )因素对测定的 2 3项正常血液生化指标没有显著影响。  相似文献   
966.
967.
A new stain for identification of avian leukocytes   总被引:3,自引:0,他引:3  
Differential staining of avian leukocytes was achieved within 6 min following brief fixation in a methanolic solution of C.I. acid red 360 followed by immersion in a mixture containing C.I. basic blue 41, C.I. basic blue 141, and C.I. acid red 52. Heterophils contained black angular and punctate granules. Eosinophils contained bright purple granules. Lymphocytes displayed red nuclei and blue cytoplasm. Monocytes contained red-brown nuclei and lavender cytoplasm. Basophils showed red-orange granules. Thrombocytes stained deep purple. Compared to traditional panoptic stains like Wright's or Giemsa's, the new staining method provides brighter colors, more precise details of cellular structures, and shorter staining time. Significantly, it facilitates identification of avian leukocyte species based on differences in color as well as differences in size and shape.  相似文献   
968.
饥饿对银鲫血液组分和卵巢发育的影响   总被引:17,自引:0,他引:17  
对银鲫 (Carassiusauratusgibelio)进行投喂、饥饿 (1~ 4周 )、饥饿投喂 (饥饿 2周再投喂 2周 )处理后 ,测定其血液组分和卵巢发育的指标。结果表明 :饥饿处理后银鲫血液中血糖、甘油三酯的含量显著降低 ;红细胞数量、血红蛋白含量和胆固醇含量先显著降低 ,随后回升到投喂组水平 ;在饥饿过程中白细胞的数量、红细胞的长短径、红细胞沉降率和总蛋白均无明显变化。饥饿投喂处理的银鲫血液中红细胞数量、甘油三酯和胆固醇含量与投喂组无差异 ,但血糖含量仍显著低于投喂组 ,而白细胞数和血红蛋白含量显著高于投喂组。饥饿 4周延缓了银鲫卵巢发育 ,其性腺成熟系数和卵径均显著低于投喂组 ;饥饿投喂组的性腺成熟系数和卵径仍显著低于投喂组。分析说明饥饿阻碍了银鲫的卵巢发育 ,而饥饿对银鲫血液组分的影响在再投喂后得到恢复。  相似文献   
969.
目的 采用幼兔离体心脏模型。模拟临床上可能出现的含血停搏液Ca^2 浓度变化,探讨适宜于未成熟心肌保护的Mg^2 浓度。方法 3-4周龄长耳白兔,依照含血停搏液不同Mg^2 浓度(0.6mmol/L,4.0mmol/L,8.0mmol/L,120mmol/L,16.0mmol/L)随机分为5组,建立Langendorff离体心脏灌注模型。采用Ca^2 浓度1.2-1.5mmol/L的含血停搏液,运用温血停搏液诱导停搏,冷血停搏液间断灌注,低温保护,终末温血停搏液控制性再灌注技术,观察以下指标:1、血流动力学指标;实验前后恢复率;心率,主动脉流量,冠脉流量,心排量,左室收缩压和左室舒张末压;2、心肌含水量;3、冠脉流出液乳酸盐含量;4、心肌肌酸激酶和乳酸脱氢酶漏出率;5、心肌细胞内Na^2 ,Ca^2 含量;6、心肌组织ATP含量;7、心肌组织SOD活性,MDA含量;8、心肌超微结构。结果 1、心率恢复率,主动脉流量恢复率及左室收缩压恢复率组间总体差异无显著性。而冠脉流量恢复率,心排量恢复率和左室舒张末压恢复率以Mg^2 浓度8.0mmol/L和12.0mmol/L为优,0.4mmol/L组最差。2、心肌含水量以Mg^2 浓度8.0mmol/L和12.0mmol/L为最低。3、冠脉流出液乳酸盐含量0.4mmol/L组,8.0mmol/L和12.0mmol/L组高于欺科2组。4、心肌乳本能部氢酶漏出率以8.0mmol/L组最低,而肌酸激酶漏出率以8.0mmol/L和12.0mmol/L组为最低。5、心肌细胞内Na^ 、Ca^2 含量;6、心肌组织ATP含量;7、心肌组织SOD活性,MDA含量;8、心肌超微结构。结果:1、心率恢复率,主动脉流量恢复率及左室收缩压恢复率组间总体差异无显著性。而冠脉流量恢复率,心排量恢复率和左室舒张末压恢复率以Mg^2 浓度8.0mmol/L和12.0mmol/L为优,0.4mmol/L组最差。2、心肌含水量以Mg^2 浓度8.0mmol/L和12.0mmol/L为最低。3、冠脉流出液乳酸盐含量0.4mmol/L组最差。2、心肌含水量以Mg^2 浓度8.0mmol/L和12.0mmol/L为最低。3、冠脉流出液乳桎卤含量0.4mmol/L组,8.0mmol/L和12.0mmol/L组高于其余2组。4、心肌乳酸脱氢酶漏出率以8.0mmol/L组最低,而肌酸激酶漏出率以8.0mmol/L和12.0mmol/L组为最低。5、心肌细胞内Na^2 含量以8.0mmol/L和12.0mmol/L组为最低,而心肌细胞内Ca^2 含量以8.0mmol/L组最低。6、心肌组织ATP含量以12.0mmol/L组为最高。7、心肌组织SOD活性以8.0mmol/L和12.0mmol/L组库最高,而MDA含量各组间总体差异无显著性。8、心肌超微结构;8.0mmol/L和12.0mmol/L组表现为基本正常未成熟心肌超微结构,而0.4mmol/L组超微结构有明显损伤表现。结论 对于未成熟心肌,当采用温血停搏液诱导停搏,冷血停搏液间断灌注,低温保护,温血停搏液终末控制性再灌注技术时,为避免含血停搏液Ca^2 浓度偏高对未成熟心肌的不利影响。应维持含血停搏液中Mg^2 浓度在8-12mmol/L。  相似文献   
970.
海鳗外周血细胞的显微结构   总被引:9,自引:1,他引:8  
对海鳗外周血液有形成分用常规Wright氏和Giemsa氏染色并进行显微观察,可鉴别出红细胞、血栓细胞、淋巴细胞、单核细胞、中性粒细胞和酸性粒细胞;还见到幼稚的、正在分裂的、分解和解体状态的红细胞;未发现碱性粒细胞。红细胞数量多,椭圆形,具椭圆形核;白细胞中血栓细胞最多,分散分布,形态多样;淋巴细胞、单核细胞、中性和酸性粒细胞与其它鱼类的基本相似。  相似文献   
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