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991.
A problem nowadays tissue engineers encounter in developing sizable tissue implants is the nonuniform spread of cells and/or extracellular matrices. Research shows such a nutrients transport restriction may be improved by employing hydrodynamic culture systems. We propose a compact model for the simulation of cell growth in a porous construct under direct perfusion. Unlike the previous model proposed in the literature, which composes a cellular scaffold sandwiched between two culture media layers, the current model includes only the scaffold layer to simplify the mathematical and computational complex. Results show the present single-layer model can predict cell spreads and the nutrient and metabolic waste distribution as accurately as does the three-layer model. Only if the hydrodynamic aspects such as the pressure and viscous stress are prominent to know, should the more sophisticated analyses with the three-layer model be employed. The compact model provides comparable investigations for the tissue-engineering construct developments.  相似文献   
992.
Pain sensation has been studied extensively, over a range of scales, from the molecular level to the entire human neural system. Thermal stimulation of pain has been widely used in the study of pain sensation. Skin thermal pain is induced through both direct (an increase/decrease in temperature) and indirect (thermomechanical and thermochemical) ways, and is governed by complicated thermomechanical–chemical–neurophysiologic responses. This paper is focused on the theoretical modeling of the underlying mechanisms in the process of skin thermal pain. A holistic model has been developed, which is composed of three sub-models, namely, transduction, transmission, and modulation and perception. The model can contribute to the understanding of thermally related pain phenomena in skin tissue and to improvements in a range of thermal therapeutic methods.  相似文献   
993.
中华眼镜蛇咬伤致局部组织损伤三种疗法的临床疗效观察   总被引:3,自引:1,他引:2  
目的对中华眼镜蛇咬伤致局部组织损伤的各种治疗方法进行疗效优劣比较,找出最佳治疗方法。方法总结我院569例中华眼镜蛇咬伤致局部组织损伤的各种治疗方法。结果治疗方法从优到劣依次是:抗蛇毒血清局部注射-糜蛋白酶局部注射-蛇伤药酒外敷-坏死组织早期切除-局部烧灼法-局部组织切开冲洗。结论中华眼镜蛇伤致局部组织损伤的治疗方法应首选抗蛇毒血清局部注射和糜蛋白酶局部注射,其次选用蛇伤药酒外敷。  相似文献   
994.
稀土元素在药用植物细胞和组织培养中的应用   总被引:5,自引:0,他引:5  
介绍了稀土元素对药用植物细胞、组织的生长及次生代谢产物合成的作用,探讨了稀土的作用机理.大量的实验证明,稀土在药用植物细胞和组织培养中具有广泛的应用前景.  相似文献   
995.
This study describes the effect of substituting dietary linoleic acid (18:2 n-6) with α-linolenic acid (18:3 n-3) on sucrose-induced insulin resistance (IR). Wistar NIN male weanling rats were fed casein based diet containing 22 energy percent (en%) fat with ~6, 9 and 7 en% saturated fatty acids (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) respectively for 3 months. IR was induced by replacing starch (ST) with sucrose (SU). Blends of groundnut, palmolein, and linseed oil in different proportions furnished the following levels of 18:3 n-3 (g/100 g diet) and 18:2 n-6/18:3 n-3 ratios respectively: ST-220 (0.014, 220), SU-220 (0.014, 220), SU-50 (0.06, 50), SU-10 (0.27, 10) and SU-2 (1.1, 2). The results showed IR in the sucrose fed group (SU-220) as evidenced by increase in fasting plasma insulin and area under the curve (AUC) of insulin in response to oral glucose load. In SU-220, the increase in adipocyte plasma membrane cholesterol/phospholipid ratio was associated with a decrease in fluidity, insulin stimulated glucose transport, antilipolytic effect of insulin and increase in basal and norepinephrine stimulated lipolysis in adipocytes. In SU-50, sucrose induced alterations in adipocyte lipolysis and antilipolysis were normalized. However, in SU-2, partial corrections in plasma insulin, AUC of insulin and adipocyte insulin stimulated glucose transport were observed. Further, plasma triglycerides and cholesterol decreased in SU-2. In diaphragm phospholipids, the observed dose dependent increase in long chain (LC) n-3 PUFA was associated with a decrease in LC-n-6 PUFA but insulin stimulated glucose transport increased only in SU-2. Thus, this study shows that the substitution of one-third of dietary 18:2 n-6 with 18:3 n-3 (SU-2) results in lowered blood lipid levels and increases peripheral insulin sensitivity, possibly due to the resulting high LCn-3 PUFA levels in target tissues of insulin action. These findings suggest a role for 18:3 n-3 in the prevention of insulin resistant states. The current recommendation to increase 18:3 n-3 intake for reducing cardiovascular risk may also be beneficial for preventing IR in humans.  相似文献   
996.
五唇兰种子离体培养的研究   总被引:2,自引:0,他引:2  
伍成厚  叶秀粦  梁承邺 《广西植物》2005,25(2):149-151,i004
授粉90d的五唇兰种子95%具球形胚,无菌条件下播种于培养基3个月后种子最高萌发率达到 90%。ABA和高浓度的NH4NO3抑制种子的萌发。NAA和BA促进种子的萌发,最适浓度为BA0.2mg· L 1+NAA0.5mg·L 1。400mg·L 1的谷氨酰胺可促进原球茎生长。2000mg·L 1的蛋白胨促进原球茎发 育成苗。  相似文献   
997.
研究发光二极管(1ight-emittingdiode,Um)直肠内照射对大鼠实验性溃疡性结肠炎(ulcerative colitis,UC)的抗过氧化损伤以及促进结肠粘膜组织的修复作用。34只大鼠随机分成3组:正常对照组10只、病理模型组12只与病理模型+LED照射治疗组12只.研究中采用乙酸局部刺激复制大鼠UC模型,其中LED治疗组应用LED结肠内照射,1日1次,共10d。其后观察各组的病理变化,血清过氧化损伤水平。结果显示,LED结肠内照射能够促使实验性溃疡性结肠炎的组织修复;显著降低溃疡性结肠炎大鼠血清MDA水平、升高SOD活性。实验表明LED结肠内照射实验性溃疡性结肠炎大鼠具有抗过氧化损伤作用以及促进结肠粘膜组织的修复作用。  相似文献   
998.
通过对安菜组织培养的培养基种类、激素配比、碳源的研究,得出适于安菜侧芽分化生长的最佳培养基为MS+6-BA0.5mg/L+NAA0.2mg/L。诱导愈伤组织以2,4-D浓度在0.2mg/L~0.5mg/L之间最佳。碳源以蔗糖,浓度3%最佳。以IBA0.5mg/L~1.5mg/L浓度诱导生根效果最好。  相似文献   
999.
Summary Stem segments from apical shoot tips of Polygala myrtifolia were used as primary explants to establish in vitro cultures. Axillary shoots produced on non-contaminated explants were excised and recultured in the same medium to increase the stock of shoot cultures. Equal molar concentrations of five cytokinins [2-isopentenyladenine, kinetin, zeatin, N 6-benzyladenine (BA), and adenine] were tested for ability to induce axillary shoot development from double-node stem segments. The highest rate of axillary shoot proliferation was induced on Murashige and Skoog agar medium supplemented with 1.8 μM BA. Seven indole-3-acetic acid (IAA) concentrations (0, 2.9, 5.7, 8.6, 11.4, 14.3, 17.1 μM) were tested to determine the optimum conditions for in vitro rooting of microshoots. Up to 72% of the microshoots rooted with 14.3 μM IAA. Other auxins tested, α-naphthaleneacetic acid and indole-3-butyric acid, were less effective than IAA in inducing adventitious root formation. All rooted plantlets having more than three roots were successfully established in soil.  相似文献   
1000.
白刺组织培养技术的研究   总被引:18,自引:2,他引:16  
试验选用唐古特白刺幼嫩茎段和叶片作为材料,研究白刺不同外植体的离体培养技术。结果表明,白刺带芽嫩茎是诱导丛生芽的良好外植体,而叶片是诱导愈伤组织的良好外植体;白刺的最适增殖、壮芽培养基是:MS BA0.5mg/L NAA1.0mg/L GA32.0mg/L;最适生根培养基是:l/2MS IBA0.5mg/L;愈伤组织诱导培养基是:MS 2,4-D0.5~1.0mg/L。  相似文献   
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