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81.
Objective To investigate the effect of rosiglitazone on p38 mitogen-activated protein kinase (p38MAPK) pathway in polycystic kidney cyst-lining epithelial cells. Methods The cyst-lining epithelial cells (PKD cells) from human polycystic kidney were treated with rosiglitazone (10 μmol/L), peroxisome proliferator-activated receptor-γ (PPARγ) inhibitor GW9662 (10 μmol/L), rosiglitazone (10 μmol/L) +GW9662 (10 μmol/L), p38MAPK specific inhibitor SB203580 (10 μmol/L), SB203580 (10 μmol/L)+ rosiglitazone(10 μmol/L) for 2 hours followed by epidermal growth factor (EGF) stimulation. Protein expressions of p38, phuspho-p38 (p-p38) and proliferating cell nuclear antigen (PCNA) were detected by Western blot. p38 mRNA was examined by RT-PCR. Expression of c-fos and c-jun was observed by immunocytochemistry. Results (1) EGF markedly up-regulated the expressions of p38, p-p38, PCNA, c-fos anti c-jun compared with control group (P<0.01). (2) Compared with EGF treated group, rosiglitazone significantly reduced p38 activation and mRNA expression (P<0.01, respectively). Rosiglitazone, rosiglitazone+SB203580 could significantly down-regulated p-p38, PCNA, c-fos and c-jun expression (P<0.01, respectively) with no significant difference between these two groups. (3) GW9662 partially reversed the reduction effect of rosiglitazone. Conclusions Rosiglitazone can inhibit proliferation of autosomal dominant polycystic kidney disease cyst-lining epithelial cells partially through down-regulating p38 activation and reducing c-fos, c-jun and PCNA expression. The above effect of rosiglitazone is in part PPARγ-independcnt. 相似文献
82.
目的 研究Ki67、P53及微血管密度(microvessel density,MVD)在大肠肿瘤中的表达,探讨其与大肠肿瘤癌变的关系及作为早期癌变生物学标志物的可能性。方法 采用免疫组化技术分别测定正常大肠黏膜、大肠息肉及大肠癌组织标本中Ki67、P53及MVD值,共80例,分析其变化规律及相关性。结果 在正常黏膜、大肠息肉、大肠癌组中的Ki67标记指数逐渐增高(分别为11.00±10.70、39.64±17.70、52.96±26.40),组间比较差异显著(P=0.0001)。正常黏膜组P53蛋白均为阴性,大肠癌组P53蛋白表达的阳性率明显高于息肉组(P=0.0001)。Ki67、P53蛋白表达与性别、年龄、病程、病变部位、大小、大肠癌的病理类型、Dukes分期均无相关性。正常黏膜、大肠息肉、大肠癌组的MVD值(14.80±5.10、19.70±7.84、36.56±20.40)逐渐上升,3组差别显著(P=0.0001)。大肠癌中Dukes C、D期的MVD值(40.56±3.49)明显高于A、B期(29.50±2.45)(P=0.016)。Ki67与P53在各种组织中的表达呈正相关(r=0.5149,P=0.015)。联合检测Ki67及P53鉴别大肠良恶性病变的敏感度(70.37%)低于单侧Ki67(96.30%),但特异度(94.34%)明显增高。结论 Ki67标记指数可反映细胞增殖状态,指数高的大肠腺瘤易发生癌变。MVD值高的大肠癌易发生转移,MVD可作为判断大肠癌预后的参考指 相似文献
83.
肝癌患者血清P-选择素测定及临床意义 总被引:2,自引:0,他引:2
目的:研究肝癌患血清P-selection(P-sel)在肝癌复发和转移中的作用。方法:采用ELISA法分别测定原发性肝癌患和对照组血清P-选择素的含量,同时测定AFP含量。结果:肝癌患P-sel含量显高于正常人,且与AFP含量呈线性正相关,术后2周浓度降低;P-sel含量以Ⅰ、Ⅲ和Ⅳ期肝癌患显高于Ⅰ期患;且大肝癌患显高于小肝癌患,有癌栓组、有肝内转移组明显高于无癌栓组和无转移组。结论:P-选择素测定在原发性肝癌的诊断和检测术后复发方面有重要价值,联合检测AFP和sP-sel可提高诊断敏感性。 相似文献
84.
A brief mechanical or electrical stimulus to peripheral nerve afferents from the upper and lower limbs elicited a small and inconsistent EMG response of the orbicularis oculi muscles. This response was facilitated when the stimuli were delivered at fixed leading time intervals, of 45–300 ms, with respect to a supraorbital nerve electrical stimulus. Also, the peripheral nerve stimulus modified the conventional blink reflex responses, inducing facilitation of R1 and inhibition of R2. These results suggest a complex processing of sensory inputs from the face and the limbs at the brainstem, where they are probably integrated in a network of interneurons influencing the excitability of facial motoneurons. 相似文献
85.
K562/ADM耐药细胞株的建立及其生物学特性的初步观察 总被引:9,自引:2,他引:7
我们建立的K562/ADM耐药细胞株,在ADM浓度为2.4μg/m1(4.46μM)中已稳定培养3.5个月,传了30—35代,K562/ADM亦具有多药耐受件(Multidrug Resistance,MDR)的特点,对ADM、VCR、AT—1258和DDP的耐受性分别为K562的114.7、94.0、13.3和7.4倍,但对5—FU不产生交叉耐药。K562和K562/ADM的倍增时间分别为19.2h和52.8h,集落生成率分别为37.5%和11.1%,K562染色体数为34—68,中位数为56;K562/MDM染色体数为32—90,中位数为50,K562/ADM可做为耐药机理和克服耐药措施研究的极好模型。 相似文献
86.
Current knowledge on the anatomy of area 3a of the cat mainly derives from the cyto- and myeloarchitectonic study of Hassler and Muhs-Clement (J Hirnforsch 6:377, 1964). Previous investigations in the cat had failed to identify a cortical region comparable to monkey's area 3a. In the present study, Nissl, myelin, acetylcholinesterase, and cytochrome oxidase staining techniques were applied to coronal and sagittal serial sections of the cat brain. Area 3a appears as a slender band of cortex between areas 4 and 3b, and in Nissl-stained sections it is mainly characterized by an attenuated granular layer IV, overlying a thin layer V with pyramidal cells of various sizes, including a few large ones. These cytoarchitectonic features are sufficient to differentiate area 3a from neighboring areas, although the borders between them are not sharp in many cases. After the Nissl staining, the acetylcholinesterase staining proved to be the most helpful in defining the structure and borders of area 3a. Acetylcholinesterase staining was dense in layer I (in contrast with a lighter staining of outer layer I in area 4), and light in layers II and IIIa, changing to moderate in IIIc and IV (a pattern which is accentuated in area 3b). Myelin and cytochrome oxidase techniques also yielded differential staining patterns of area 3a and neighboring areas 4 and 3b, although the borders were not easily drawn with these techniques. Whereas our cyto- and myeloarchitectonic findings were comparable to those of Hassler and Muhs-Clement ('64) and applied well to area 3a in the convexity of the hemisphere, we found that most of the area 3a described by these authors in the medial face of the hemisphere had a number of distinguishing architectonic (as well as connectional and physiological) features which enabled us to define it as a separate area (7m). The techniques we used to delineate area 3a are compatible with most current procedures of histo- and immunohistochemical staining of the brain, and may also provide valuable supporting data for electrophysiological studies. 相似文献
87.
The spinal cord dorsal horn contains neural mechanisms which can greatly facilitate pain. We have recently shown that ‘illness’-inducing agents, such as intraperitoneally administered lipopolysaccharide (LPS; bacterial endotoxin), can produce prolonged hyperalgesia. This hyperalgesic state is mediated at the level of the spinal cord via activation of the NMDA-nitric oxide cascade. However, prolonged neuronal depolarization is required before such a cascade can occur. The present series of experiments were aimed at identifying spinal neurotransmitters which might be responsible for creating such a depolarized state. These studies show that LPS hyperalgesia is mediated at the level of the spinal cord by substance P, cholecystokinin and excitatory amino acids acting at non-NMDA sites. No apparent role for serotonin or kappa opiate receptors was found. 相似文献
88.
The locust prosternum carries a population of long filiform hairs that are very sensitive to air currents. The sensory afferent neurons that innervate the hairs make strong monosynaptic connections with an identified intersegmental interneuron (A4I1) which is known to contact motor neurons that supply muscles controlling wing angle during flight. In order discover how the synapse between the afferents and interneuron A4I1 might be modulated, the afferents were labelled intracellularly by backfilling with horseradish peroxidase to reveal their central terminals which lie in the prothoracic ganglion. A postembedding immunogold method was used to make a quantitative assessment of the prevalence of immunoreactivity for GABA and glutamate in processes presynaptic to the afferent terminals. In one afferent neuron, where 77 synapses were examined, 40 (52%) of the presynaptic processes were immunoreactive for GABA. When adjacent sections through the same terminal branches were labelled with the two antibodies, it was demonstrated that GABA- and glutamate-like immunoreactivity was present in different populations of presynaptic processes. A series of 110 ultrathin sections was cut through one set of afferent terminal branches and alternate grids were stained with GABA and glutamate antibodies. From these sections, the terminals were reconstructed and the position of 35 input and 21 output synapses mapped. Of the 35 input synapses, 18 (51%) were immunoreactive for GABA, 14 (40%) were immunoreactive for glutamate and 3 (9%) were unlabelled by either antibody. On these terminals, the different classes of input synapses appeared to be intermingled at random with the output synapses made by the afferent, and no pattern govering synapse distribution could be discerned. © 1994 Wiley-Liss, Inc. 相似文献
89.
大鼠延髓腹侧面头端应用毒扁豆碱引起血压升高和心率加快,伴有延髓腹侧面头端胆碱酯酶活性降低和脊髓蛛网膜下腔灌流液中P物质样免疫反应活性升高。在延髓腹侧面头端应用阿托品或脊髓蛛网膜下腔注射P物质拮抗剂D-脯~2,D-苯丙~7,D-色~9-P物质均可阻断毒扁豆碱的心血管效应。脊髓蛛网膜下腔注射P物质抗血清或辣椒素均可减弱毒扁豆碱的升压反应。实验结果提示,毒扁豆碱作用于延髓腹侧面头端的M受体,兴奋了延髓-脊髓P物质能神经元下行通路,使之释放P物质,引起交感肾上腺髓质系统兴奋,从而使血压升高和心率加快。 相似文献
90.
背景与目的:探讨莱菔硫烷对人膀胱癌细胞(T24)细胞周期的影响及作用机制。材料与方法:采用噻唑蓝(MTT)法研究不同浓度的莱菔硫烷对T24细胞生长的抑制作用并测定其半数抑制浓度(IC50);采用流式细胞仪检测莱菔硫烷对T24细胞周期的影响;采用westernblot研究莱菔硫烷对T24细胞中细胞周期蛋白依赖激酶抑制剂P16和P27的表达情况。结果:在较低剂量范围内(≤40μmol/L),随着作用剂量的增加,莱菔硫烷对T24细胞的生长的抑制作用也明显增强。10、20、40μmol/L莱菔硫烷的抑制率分别为(12.5±3.95)%,(25.0±2.50)%、(50.0±5.33)%;在较高剂量(60μmol/L~160μmol/L)时,这种抑制作用不再呈剂量依赖性;莱菔硫烷作用72h后的IC50值为(51.12±7.10)μmol/L;莱菔硫烷能使T24细胞周期阻滞于G0/G1期,20μmol/L莱菔硫烷作用48h后,在G0/G1峰之前出现凋亡峰;20μmol/L莱菔硫烷作用于T24细胞8、12、24h后能明显诱导P27蛋白的表达,作用早期(8h)时能诱导P16蛋白的表达。结论:莱菔硫烷能抑制T24细胞生长并使该细胞周期阻断在G0/G1期,其作用机制主要是通过诱导P27蛋白及早期诱导P16蛋白来实现的。 相似文献