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1.
In this study, we describe a cluster of tyraminergic/octopaminergic neurons in the lateral dorsal deutocerebrum of desert locusts (Schistocerca gregaria) with descending axons to the abdominal ganglia. In the locust, these neurons synthesize octopamine from tyramine stress-dependently. Electrophysiological recordings in locusts reveal that they respond to mechanosensory touch stimuli delivered to various parts of the body including the antennae. A similar cluster of tyraminergic/octopaminergic neurons was also identified in the American cockroach (Periplaneta americana) and the pink winged stick insect (Sipyloidea sipylus). It is suggested that these neurons release octopamine in the ventral nerve cord ganglia and, most likely, convey information on arousal and/or stressful stimuli to neuronal circuits thus contributing to the many actions of octopamine in the central nervous system.  相似文献   
2.
通过探索性研究对鹿瓜多肽注射剂质量现状及存在问题进行评价,并对现行质量标准进行优化。首先,对影响终产品新鲜度的因素进行考察。建立丹磺酰氯柱前衍生-HPLC 法测定鹿瓜多肽注射剂中 8 种生物胺的含量,结果显示个别企业的样品中检出较高浓度的尸胺;采用免疫亲和柱净化-柱后光化学衍生-HPLC -FLD 法测定鹿瓜多肽注射剂及中间提取液中黄曲霉毒素 B1、B2、G1 和 G2 的含量,并采用自动电位滴定法测定甜瓜子原料的酸价和过氧化值,结果表明部分企业生产原料甜瓜子存在霉变、酸败等问题,应在新鲜度方面给予重视。其次,优化了鹿瓜多肽注射剂质量标准中高分子量物质和多肽含量测定的方法。采用 Tricine-SDS-PAGE 电泳法代替凝胶色谱法测定高分子量物质,提高了测定的准确性;采用试剂盒法代替福林酚法测定多肽含量,该法操作简便、专属性更强,适用于大批量样品的快速测定。最后,对鹿瓜多肽注射剂质量标准中缺失的溶血与凝聚、生物学活性测定项目进行研究。建立直接观察法结合酶标仪测定法考察溶血与凝聚反应,结果各企业样品均无溶血与凝聚现象;采用 CCK-8 法考察鹿瓜多肽注射剂对 THP-1 细胞增殖的抑制作用,以此评价其抗炎活性,结果显示鹿瓜多肽注射剂对 THP-1 细胞具有增殖抑制作用,各企业样品的体外抗炎效果具有一定差异。探索性研究结果显示,鹿瓜多肽注射剂原材料、中间产品及终产品的安全性均存在一定隐患,表明本品的整体质量水平一般,且现行质量标准存在缺陷,亟待提高。  相似文献   
3.
蔡浩斌  黄忠仕  黄岑汉 《重庆医学》2015,(2):165-167,170
目的:观察壮精合剂对初老大鼠行为学及脑单胺类神经递质的影响,探讨其抗衰老的作用机制。方法选用12月龄,体质量(300±20)g。雌性初老大鼠50只,建立模型,分为5组:空白对照组、壮精合剂高剂量组、壮精合剂中剂量组、壮精合剂组低剂量组、阳性对照组,每组10只。各组分别灌胃相应药物8周后,采用Morris水迷宫检测各组大鼠的空间学习记忆行为能力及采用高效液相色谱‐荧光检测法检测各组大鼠大脑皮层、海马单胺类神经递质含量。结果与空白对照组比较,壮精合剂高、中剂量组及阳性对照组均能使初老大鼠学习记忆能力有所改善,并能提高其大脑皮层及海马区单胺类经递质含量。壮精合剂高剂量组与阳性对照组比较在改善学习记忆能力方面差异有统计学意义(P<0.05),在提高大脑皮层及海马区单胺类经递质含量方面效果最为显著(P<0.05)。结论壮精合剂能有效改善初老大鼠的学习记忆能力,其作用机制可能与调节大脑内单胺类神经递质有关。  相似文献   
4.
5.
目的探讨peroxin 1(PEX1)复合杂合突变致过氧化物酶体生物发生缺陷病(PBD)的临床及基因特征。方法回顾分析1例PBD患儿的临床资料,并复习相关文献。结果患儿,男,4岁6个月,智力发育迟缓,无其他明显异常。基因检测发现患儿PBD相关PEX1基因存在2个尚未报道的杂合突变,c.539AC(p.Lys180Thr)和c.2704_2708delTTTAT(p.Phe902fs),符合常染色体隐性遗传模式。确诊为PBD1B型。结论 PBD患者临床表型多样,其严重程度与PEX1基因的突变类型有关,基因检测可确诊。  相似文献   
6.
《Neurobiology of aging》2014,35(12):2691-2700
Depression and aggression in Alzheimer's disease (AD) are 2 of the most severe and prominent neuropsychiatric symptoms (NPS). Altered monoaminergic neurotransmitter system functioning has been implicated in both NPS, although their neurochemical etiology remains to be elucidated. Left frozen hemispheres of 40 neuropathologically confirmed AD patients were regionally dissected. Dichotomization based on depression and aggression scores resulted in depressed/nondepressed (AD + D/AD − D) and aggressive/nonaggressive (AD + Agr/AD − Agr) groups. Concentrations of dopamine, serotonin (5-HT), (nor)epinephrine ((N)E), and respective metabolites were determined using reversed-phase high-performance liquid chromatography. Significantly lower 3-methoxy-4-hydroxyphenylglycol (MHPG) and higher homovanillic acid levels were observed in Brodmann area (BA) 9 and 10 of AD + D compared with AD − D. In AD + Agr, 5-hydroxy-3-indoleacetic acid (5-HIAA) levels in BA9, 5-HIAA to 5-HT ratios in BA11, and MHPG, NE, and 5-HIAA levels in the hippocampus were significantly decreased compared with AD − Agr. These findings indicate that brain region-specific altered monoamines and metabolites may contribute to the occurrence of depression and aggression in AD.  相似文献   
7.
This study was aimed to observe that extremely low frequency magnetic field (ELF-MF) may be relevant to changes of major neurotransmitters in rat brain. After the exposure to ELF-MF (60 Hz, 2.0 mT) for 2 or 5 days, we measured the levels of biogenic amines and their metabolites, amino acid neurotransmitters and nitric oxide (NO) in the cortex, striatum, thalamus, cerebellum and hippocampus. The exposure of ELF-MF for 2 or 5 days produced significant differences in norepinephrine and vanillyl mandelic acid in the striatum, thalamus, cerebellum and hippocampus. Significant increases in the levels of serotonin and 5-hydroxyindoleacetic acid were also observed in the striatum, thalamus or hippocampus. ELF-MF significantly increased the concentration of dopamine in the thalamus. ELF-MF tended to increase the levels of amino acid neurotransmitters such as glutamine, glycine and γ -aminobutyric acid in the striatum and thalamus, whereas it decreased the levels in the cortex, cerebellum and hippocampus. ELF-MF significantly increased NO concentration in the striatum, thalamus and hippocampus. The present study has demonstrated that exposure to ELF-MFs may evoke the changes in the levels of biogenic amines, amino acid and NO in the brain although the extent and property vary with the brain areas. However, the mechanisms remain further to be characterized.  相似文献   
8.
目的 合成一种具有游离伯胺的卡莫司他衍生物.方法 以对羟基苯乙酸为原料,经4步反应得到目标化合物.结果与结论 成功制备了目标产物,所得产物的化学结构经1HNMR、MS确认.  相似文献   
9.
The free amino acid composition and biogenic amine content were analysed in pasteurised goat milk cheeses produced in different regions in Spain. These goat cheeses are made with pasteurised milk to which a mesophilic starter culture is added; they are enzymatically coagulated, uncooked, pressed cheeses. They have a firm texture with a slight but typical goat milk aroma and flavour. The total free amino acids varied markedly among the samples, ranging from 1400 to 28,000 mg kg−1 DM (dry matter). Of the 20 amino acids analysed, the most abundant were leucine, proline, valine, glutamic acid, lysine, glutamine, ornithine and γ-aminobutyric acid, which accounted for over 60% of the total free amino acids. The goat milk cheeses presented low concentrations of biogenic amines, the most abundant being tyramine and/or histamine, with values ranging from 4.2 to 50.7 and from 10.2 to 60.5 mg kg−1 DM, respectively. Total biogenic amine content ranged between 26.4 mg kg−1 DM and 175.1 mg kg−1 DM, and was always below the level that is considered dangerous for humans. Therefore, taking into consideration the concentrations of BAs, these goat milk cheeses, produced under good hygienic conditions, can be considered safe for consumers.  相似文献   
10.
Waters receiving textile discharges can exhibit genotoxic and mutagenic activity, which has been related to the presence of dyes and aromatic amines as synthesis precursors or byproducts. The aim of this study was to identify dyes and aromatic amines in water samples impacted by textile discharges, and to evaluate the genotoxic responses of these samples using the Salmonella/microsome assay in strains TA98 and YG1041, and the Fpg‐modified comet assay in the RTL‐W1 fish cell line. The genotoxicity of river samples downstream of the discharge was greater than the upstream samples in both of the Ames tests. The Fpg‐modified comet assay detected similar levels of DNA damage in the upstream and downstream samples. Mutagenicity was not detected with TA98, except for the Quilombo River samples, but when YG1041 was used as the tester strain mutagenicity was detected for all sites with a very different profile in upstream sites relative to the other sites. The mutagenic response strongly indicated that aromatic amines or dyes were contributing to the mutagenic activity downstream. The impact of textile discharges was also confirmed by chemical analysis, because the highest concentrations of azo dyes and aromatic amines were detected in the river downstream. This study shows the value of combining assays measuring complementary endpoints to better characterize the mutagenicity of environmental samples, with the advantage that this approach provides an indication of what classes of compounds are responsible for the effect. Environ. Mol. Mutagen. 57:559–571, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
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