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131.
目的:探讨CD8^+CD28^+T细胞钙离子浓度的变化与心脏移植急性排斥反应(AR)的相关关系。方法:用流式细胞仪检测正常SD大鼠组(T0组)、同种心脏移植组(T1)(Wistar→SD大鼠)术后第1、3、5、7天CD8^+CD28^+T细胞内钙离子浓度的变化,分析CD8^+CD28^+T细胞内钙离子浓度的变化与心脏移植AR程度的相关关系。结果:CD8^+CD28^+T细胞内钙离子浓度升高与AR严重程度成正相关,相关系数为0.469,相关具有显著性(P〈0.05)。结论:心脏移植后CD8^+CD28^+T细胞内钙离子浓度显著升高,其升高程度与AR严重程度成正相关。  相似文献   
132.
在标记脐血造血祖细胞表面抗原(HPCA),CD34中,比较抗-HPCA-2-FITC和Tk3(纯抗体)标记的CD(34+)细胞在流式细胞仪分析中的荧光特征及两种单抗标记的CD(34+)细胞与体外培养的粒单细胞集落形成单位(CFU-GM),红系爆发形成单位(BFU-E),和混合集落形成单位(CFU-Mix)的相关性。结果发现脐血有核细胞中,抗HPCA-2阳性细胞占1.05±0.72%(n=13),Tk3阳性细胞占2.06±1.25%(n=8),差别显著(P<0.05)。每毫升脐血两种抗体标记的细胞分别为96.56±56.64和231.40±163.93(P<0.05)。尽管HPCA-2阳性细胞与Tk3阳性细胞数量呈显著正相关(r=0.875,P<0.01),前者与CFU-GM,BFUE,CFU-Mix及集落总数CFUs均呈正相关,而后者仅与CFU-GM,CFUs相关。研究提示在检测造血祖细胞时,用抗-HPCA-2-FITC代替Tk3可降低假阳性,获得较好的OD(34+)细胞与CFU间的线性关系。  相似文献   
133.
The chemokines, macrophage inflammatory protein-1 (MIP-1) and its subunit MIP-1β, induce an intense fever in the rat when they are injected directly into the anterior hypothalamic, pre-optic area (AH/POA), a region containing thermosensitive neurons. The purpose of this study was to compare the central action on body temperature (Tb) of MIP-1β with that of interleukin-6 (IL-6), which also has been implicated in the cerebral mechanism underlying the pathogenesis of fever. Following the stereotaxic implantation in the AH/POA of guide cannulae for repeated micro-injections, radio transmitters which monitor Tb continuously were inserted intraperitoneally in each of 15 male Sprague-Dawley rats. Each micro-injection was made in a site in the AH/POA in a volume of 1.0 μl of pyrogen-free artificial CSF, recombinant murine MIP-1β, or recombinant human IL-6. MIP-1β in a dose of 25 pg evoked an intense fever characterized by a short latency, a mean maximum rise in Tb of 2.4 ± 0.21°C reached by 3.7 ± 0.42 hr, and a duration exceeding 6.5 hr. Injected into homologous sites in the AH/POA, IL-6 induced a dose dependent fever of similar latency and a mean maximal increase in Tb of 1.2 ± 0.25°C, 1.8 ± 0.15°C, and 2.1 ± 0.22°C and duration of 6.2 ± 1.28 hr, 6.7 ± 0.49 hr, and 6.8 ± 0.65 hr when given in doses of 25, 50, and 100 ng, respectively. These results show that MIP-1β and the highest dose of IL-6 induce a fever of comparable intensity, but MIP-1β exerts its action in a much lower concentration. Thus, the de novo synthesis and subsequent action of the MIP-1 family of cytokines on neurons of the AH/POA in response to a pyrogen challenge apparently play a functional role in the pathogenesis of fever. Further, the endogenous activity of IL-6 in the hypothalamus which is enhanced in response to a lipopolysaccharide also may reflect its essential part in the acute phase response to a bacterial challenge. Copyright © 1994 Wiley-Liss, Inc.  相似文献   
134.
Exposure of H69 small cell lung carcinoma cells to nicotinic agonists resulted in a significant increase (up to 100%) in cell number after 6 to 12 days. The effect of nicotine (10−8 M to 10−4 M) was both dose and time dependent as was that of another nicotinic agonist cytisine (10−6 M to 10−4 M). Interstingly, both the nicotine and cytisine induced increases in H69 cell number were blocked by α-bungarotoxin, as well as d-tubocurarine a nicotinic blocker which appears to interact with most nicotinic receptors. These results suggest that the nicotine induced increase in cell number is mediated through an interaction at the nicotinic α-bungarotoxin receptor. This idea is further supported by experiments which show (1) that H69 cells possess high affinity α-bungarotoxin sites (Kd = 25 nM, Bmax = 10.4 fmol/106 cells) with the characteristics of a nicotinic α-bungarotoxin receptor and (2) that the potencies of nicotinic receptor ligands in the α-bungarotoxin binding assay were similar to those observed in the functional studies. Northern analysis showed that mRNA for α7, a putative nicotinic α-bungarotoxin binding subunit, and for α5 were present in H69 cells. The present data provide further evidence that nicotine increases cell number in small cell lung carcinoma and are the first to show that this effect is mediated through an interaction at the nicotinic α-bungarotoxin receptor population. These results suggest that the α-bungarotoxin site may be involved in modulating proliferative responses in neuroendocrine derived SCLC cells.  相似文献   
135.
Immunosuppression of immunoglobulin synthesis seen in patients with multiple myeloma is in part due to immunosuppressive CD5 positive B cells. In a 13 year longitudinal study of an IgA-deficient blood donor who developed multiple myeloma, the presence of immunosuppressive CD5 positive B cells and T cells preceded the diagnosis of overt multiple myeloma and the appearance of immunosuppressive monocytes. These data argue that certain immune defects may be involved in the development of myeloma and are not simply a consequence of overt malignancy.  相似文献   
136.
目的探讨CD26/DPPⅣ、半乳糖凝集素3免疫组织化学染色及其联合检测在甲状腺癌诊断中的应用价值。方法采用免疫组织化学EnVision二步法检测了114例良恶性甲状腺肿瘤组织中CD26/DPPⅣ及半乳糖凝集素3的表达。结果CD26/DPPⅣ及半乳糖凝集素3在正常甲状腺组织中无表达,在甲状腺腺瘤及滤泡癌中少有表达,在大多数甲状腺乳头状癌中呈不同程度的阳性表达。相对于甲状腺腺瘤而言,CD26/DPPⅣ诊断乳头状癌的敏感性、特异性、诊断准确率、阳性预测值、阴性预测值及kappa值分别为86.8%、97.2%、90.4%、98.3%.79.5%及0.80,半乳糖凝集素3分别为97.1%、91.7%、95.2%、95.7%、94.3%及0.89。结论CD26/DPPⅣ及半乳糖凝集素3均是甲状腺乳头状癌较为可靠的标志物,可以辅助常规的病理检查进行乳头状癌与腺瘤的鉴别诊断,它们在甲状腺滤泡癌诊断中的应用价值尚有待于进一步的研究。  相似文献   
137.
目的研究T3期胃癌CD34与胃癌新生血管形成及淋巴结转移的关系.方法随机选取胃癌手术标本41例,其中T3N0M020例,T3N1M021例,分别进行特异性抗体免疫组化染色,并采用Image Pro Plus 5.0图像软件分析数据,计算胃癌组织CD34微血管密度(MVD)和其他相关抗体(CD44、Ⅳ型胶原、层黏蛋白)的表达,并进行统计学分析.结果CD34 MVD计数(CD34表达强度),在T3N0M0和T3N1 M0肿瘤组分别为43.10±18.22和56.24±28.36,两组比较有显著差异(P<0.05);CD44、Ⅳ型胶原、层黏连蛋白的表达强度,T3N0M0和T3N1M0肿瘤组比较无显著差异(P>0.05).结论CD34与T3期胃癌组织新生血管形成及淋巴结转移的关系密切,可作为诊断T3期胃癌淋巴结转移的参考指标.  相似文献   
138.
原发性胆囊癌CD44v6和bcl-2的表达及其与临床病理的关系   总被引:1,自引:0,他引:1  
目的 探讨CD44v6和bcl 2蛋白在原发性胆囊癌组织中的表达及其与癌组织类型、病理分级和转移状况的关系 ,以及CD44v6表达与bcl 2表达的相关性。方法 应用免疫组织化学方法检测 50例原发性胆囊癌、2 0例胆囊腺瘤和 1 0例慢性胆囊炎组织中CD44v6和bcl 2蛋白的表达。结果 胆囊癌组织中CD44v6和bcl 2表达阳性率分别为82 .0 %和 60 .0 % ,均明显高于胆囊腺瘤 (分别为 45 .0 %和 30 .0 % ,P<0 .0 5) ,并随着胆囊癌细胞分化程度的减低、病理分级的增高和转移而明显增高 (P<0 .0 5)。同时 ,CD44v6的表达与bcl 2表达呈正相关 (r =0 .36 ,P<0 .0 5)。结论 CD44v6和bcl 2均是胆囊癌高度恶性和预后不良的重要指标。胆囊癌CD44v6表达与bcl 2蛋白表达可能具有相互协同作用。  相似文献   
139.
The effects of withdrawal from continuous administration of cocaine on behavioral sensitivity to apomorphine and monoamine receptor density were examined in rats. Subdermal minipumps that delivered either saline or 20 mg/kg/day cocaine hydrochloride were implanted for 2 weeks. Apomorphine-induced stereotypy (0.5 mg/kg, SC) was examined in separate groups of rats either 4 hr or 7, 28, or 60 days after removal of the minipumps. Transient enhanced sensitivity to apomorphine-induced stereotypy occurred during the course of withdrawal. Animals withdrawn from cocaine for 4 hours did not differ from controls in their sensitivity to apomorphine, whereas animals withdrawn from cocaine for 7 days exhibited an increase in apomorphine-induced oral stereotypy relative to controls. However, the enhanced stereotypy response was no longer evident in animals withdrawn for 28–60 days. The animals were sacrificed after behavioral testing, and their brains were assayed for changes in monoamine receptor density in the frontal cortex, caudate-putamen, and nucleus accumbens. The density of 3H-SCH-23390-labeled D1 receptors was altered in all three regions examined in a time-dependent manner that paralleled the changes in behavioral sensitivity to apomorphine. There was a transient decrease in D1 receptor density that was evident by 7 days following withdrawal from continuous cocaine administration and was no longer evident 28 or 60 days posttreatment. There were no changes in 3H-spiroperidol-labeled D2 receptors, 125-pindolol-labeled β-adrenergic receptors, or 3H-ketanserin-labeled 5-HT2 receptors in any of the regions examined at both 4 hr and 7 days after termination of the cocaine infusion. These findings are discussed in terms of their relevance to developing pharmacologic treatments for withdrawal from cocaine. © 1994 Wiley-Liss, Inc.  相似文献   
140.
Liposomes as drug carriers in cancer chemotherapy have attracted considerable interest. To enhance the therapeutic effect of Adriamycin entrapped in liposomes (Lip-ADM) on human solid tumors, we investigated the therapeutic effects of Lip-ADM in combination with recombinant human tumor necrosis factor-alpha (rTNF-alpha), which is known to have specific effects on tumor vasculature. rTNF-alpha or saline solution was injected intravenously into nude mice bearing a human colon cancer strain, HC-1, at 1 hour before intravenous administration of Lip-ADM. The significant therapeutic effect of Lip-ADM in combination with rTNF-alpha was demonstrated by the evaluation with tumor growth curve and the actual tumor weights, in comparison with groups of mice treated with saline solution, rTNF-alpha alone, or with a Lip-ADM after saline. Levels of Adriamycin in tumor tissue in the Lip-ADM in combination with rTNF-alpha-treated group were higher than those in Lip-ADM with saline solution-treated group.  相似文献   
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