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71.
The effects of substance P (SP) on Salmonella minnesota R345 (Rb) binding to human peripheral blood lymphocytes (PBL) were evaluated. Two parameters of bacterial cytoadherence were considered, namely the binding lymphocytes (BL) and the number of bound-bacteria/lymphocyte (BB). The results showed that SP inhibits both BL and BB in a significant manner. Furthermore, distribution of Salmonella binding to CD4+ and CD8+ lymphocytes was studied following SP pretreatment of lymphoid cells. This neuropeptide is able to hamper the bacterial cytoadherence to both T-cell subpopulations and, in particular, the inhibitory effect on the T-suppressor/cytotoxic subset was more pronounced. These findings are discussed in terms of SP intervention in the mechanism of host protection against invading microorganisms.  相似文献   
72.
Recent immunohistochemical studies indicate the presence of a bulbospinal substance P (SP) system, as well as a bulbospinal serotonin (5-HT) system, involved in spinal pain transmission. Although electrophysiological studies indicate that SP may modulate the effects of 5-HT on post-synaptic spinal nociceptive neurons, the functional relationship between SP and 5-HT on “pain behavior” remains obscure. To bridge this gap between mechanism and behavior, the purpose of the present study was to determine specific postsynaptic behavioral effects of SP and 5-HT on local spinal nociceptive reflexes in spinally transected animals. Administration of the 5-HT agonists 5-methoxydi-methyltryptamine (5-MeODMT) (0, 0.5, 1.5, 2.0 mg/kg) and quipazine (0, 5, 10, 20 mg/kg) 2 days after transection significantly expanded the receptive field (RF) areas of three spinal reflexes, as previously reported. Intrathecal administration of SP alone (0, 0.25, 2.5, 7.5 ng) also resulted in hyperalgesia, indicated by a significant expansion of the RF areas of all three nociceptive reflexes. However, administration of SP, in animals pretreated with 5-HT agonists, decreased the 5-HT-induced expansion of RF size. Therefore, SP had opposite effects on spinal nociceptive reflexes depending on whether or not the animal was pretreated with 5-HT agonists, i.e., hyperalgesia in the absence of 5-HT agonists, and analgesia in the presence of 5-HT agonists. The two effects of SP on local spinal reflexes may be related to the anatomical organization of the two spinal SP systems: 1) SP released from primary afferents facilitates nociceptive reflexes, and 2) SP associated with the descending bulbospinal system interacts with the descending bulbospinal 5-HT system and inhibits nociceptive reflexes. The present results help explain contradictory literature regarding the effect of SP on spinal nociceptive reflexes.  相似文献   
73.
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   
74.
目的 为了解氯喹敏感和抗性株恶性疟原虫对青蒿琥酯、克林霉素及其二联用的敏感性。方法 运用Rieckmann体外微量法测定原虫对药物的敏感性。结果 氯喹敏感株恶性疟原虫对青蒿琥酯、克林霉素及青/克联用的ID50分别为2.8、3784.7及6.4/2046.6nmol/L;抗性株原虫对上述药物的ID50分别为8.1、1652.1及2.35/1409.4nmol/L。结论 抗氯喹恶性疟原虫对克林霉素无交叉抗性。青蒿琥酯与克林霉素联用在体外测定中,其抗疟作用对抗性株明显优于敏感株。  相似文献   
75.
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   
76.
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   
77.
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   
78.
We have examined 6 construction workers who developed chronic skin diseases on their hands over a period of 15 years (1970–1985). 4 developed a Trichophyton rubrum infection, and the other 2 an irritant contact dermatitis. All of them carried out jobs which caused traumatization of the skin, due to the presence of ethylene glycol and mineral oils during operation of pneumatic hammers in winter. They also suffered other types of skin trauma during their work. Construction workers may be at risk of developing an occupational skin disease involving fungal infection.  相似文献   
79.
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   
80.
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   
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