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61.
向培养液中加入15mmol/L的β-AP1-40,48h后,发现原代培养的海马细胞内Ca2+的浓度明显增高,对照组为23.9±3.6(n=51)而β-AP组为36.5±15.8(n=30),两组比较P<0.001,有非常显著性的差别。对照组的乳酸脱氢酶没有明显变化,而β-AP组在加β-AP1-4048h后乳酸脱氢酶明显增加,从52iu/L增加到105iu/L,实增加了101%。实验结果表明,β-AP1-40对培养的神经细胞有明显的毒性作用,但没有发现形态学的变化和对细胞的特异性。如在培养液中加β-AP1-40的同时再加25mg/ml的神经节苷脂(GAs)可明显减弱β-AP1-40引发的胞内Ca2+浓度和培养液中LDH浓度的升高。β-AP+GAs组胞内Ca2+浓度为27.7±5.58,与β-AP组比较,有显著性差异(P<0.01)。β-AP组海马细胞培养液中乳酸脱氢酶的浓度增高为101%,而β-AP-GAs组培养液中乳酸脱氢酶的浓度增高仅为67%。在NG108-15细胞上也获得了相同的结果。单唾液酸神经节苷脂虽有与GAs类似的作用,但较弱。这些实验结果指出,神经节苷脂和单唾液酸神经节苷脂均能拮抗β-AP1-40的毒性作用,从而对细胞可起到保护作用。  相似文献   
62.
Effector T cells fall into two subpopulations based on cytokine-secretion. Type 1 cells secrete IFN-gamma, whereas type 2 cells secrete IL-4, IL-10, and GM-CSF. NKT cells represent a third subpopulation that secretes similar cytokines and have been associated with immunoregulation. Using the TS/A adenocarcinoma, we assessed the phenotype and kinetics of tumor-infiltrating lymphocytes (TIL) in mice challenged subcutaneously in the mammary region. Flow cytometric analysis shows that T cells do not infiltrate the primary tumor site until days 7-14 following tumor challenge. Both CD4 and CD8 TILs were predominantly CD44(High) and expressed CD25, CD69, and CD95 cell surface activation markers. Activated CD4/CD44(High) TIL numbers reached peak levels at day 21 that precipitously decreased by day 28 whereas corresponding CD8 cell numbers progressively increased, however, at lower levels and with later kinetics. Intracellular cytokine staining showed that greater numbers of IL-4-producing Th2 cells were elicited and with earlier kinetics than that of IFN-gamma-producing Th1 cells. T cells co-expressing DX5 (CD3(+)/DX5(+)) emerged (>21 days), suggesting a recruitment of NK-like T cells at later stages of tumor progression. Moreover, tumors selectively up-regulated TGF-beta, MIF, and IP-10 gene expression at times as early as day 4, with peak levels at day 7 in vivo. Such gene expression remained elevated and correlated with a continued progression in tumor growth suggesting that preferential effector cell recruitment and production of select factors during different stages of tumor maturation may aid in regulating effective endogenous antitumor responses in progressive breast cancer.  相似文献   
63.
We have established the content and molecular species of immunoreactive β-endorphin (ir-β-END) and immunoreactive N-acetyl-endorphin (ir-Nac-END) in rat neurointermediate lobe by specific radioimmunoassay (RIA) and high-performance liquid chromatography after chronic administration of dopamine (DA) agonists and antagonists. The DA agonist, bromocriptine, reduces tissue levels of all major immunoreactive species, in particular the C-terminally shortened N-acetylated forms. The DA antagonist, haloperidol, proportionally increases all immunoreactive forms, except Nac-β-END1–27, thus altering the relative abundance of this species. These data indicate that DA is involved in the control of both tissue levels and processing of β-END-like peptides in the rat neurointermediate lobe.  相似文献   
64.
We have previously demonstrated by immunohistochemistry that mucosal expression of beta 2 integrins was enhanced in Crohn's disease and ulcerative colitis as compared to normal controls. We aimed, therefore, to determine whether there was a corresponding alteration in the expression of CD11a/CD18 (LFA-1), the primary lymphocyte beta 2 integrin, among the principal subsets of lamina propria lymphocytes (LPLs). Accordingly, LPLs were extracted from surgical resection specimens derived from patients with Crohn's colitis, ulcerative colitis, and from noninflamed controls. Following immunofluorescent staining, three-color flow-cytometry analysis identified LPLs on the basis of CD45 side scatter gating, which in turn, were further subdivided into CD4(+), CD8(+), and CD19(+) cells to account for the predominant T and B cells in the lamina propria. Expression patterns of CD11a, the alpha-subunit of LFA-1; CD18, the beta-subunit of LFA-1; and alpha d, a novel alpha-subunit of the beta 2 integrin family were assessed for each of these lymphocyte subsets. In Crohn's disease and ulcerative colitis there was an increased mean percentage expression of CD4(+) cells and CD11a(+) cells compared with noninflamed controls. CD11a was more likely to be expressed on CD4(+) cells in both Crohn's disease and ulcerative colitis and compared with controls and less expressed on CD19(+) cells. It is likely that an influx of CD4(+)11a(+) cells into the lamina propria accounted for these changes. These results suggest that although currently there is great interest in harnessing alpha 4 beta 7 in treatment of inflammatory bowel disease, further consideration should be given to the role of CD11a in these disease states.  相似文献   
65.
Objectives: Gouty arthritis is caused by the deposition of monosodium urate (MSU) crystals in joints, which is associated with the rise of serum urate content. This study aims to investigate the therapeutic effect of Madecassoside on gouty arthritis and hyperuricemia.

Methods: DBA/1 mice were intradermally injected with MSU to stimulate joint inflammation or intraperitoneally injected with MSU to trigger peritonitis. Moreover, ICR mice were exposed to potassium oxonate to stimulate hyperuricemia.

Results: Madecassoside repressed MSU-triggered pad swelling, joint 99mTc uptake, and joint inflammation in DBA/1 mice with gouty arthritis. Neutrophil infiltration and IL-1β & IL-6 & MCP-1 secretion was also alleviated in lavage fluids from DBA/1 mice with peritonitis due to Madecassoside treatment. Furthermore, Madecassoside decreased MSU-induced neutrophil cytosolic factor 1, caspase-1 and NLRP3 expression in mice with peritoneal inflammation. In hyperuricemic mice, Madecassoside improved renal dysfunction. Serum uric acid, BUN, and creatinine were down-regulated by Madecassoside.

Conclusion: These findings indicate that Madecassoside has potential to ameliorate inflammation in both acute gouty arthritis model and peritonitis model, probably via regulating IL-1β and NLRP3 expression.

Practical point: Madecassoside also exhibited a urate-lowering effect and a renal protective effect in hyperuricemic mice.  相似文献   

66.
67.
目的 探索Gadd45β和Gadd45γ在亚砷酸钠所致的MIHA细胞周期改变中的作用,为砷中毒的人群防治提供依据。方法 收集贵州省兴仁县雨樟镇交乐病区砷中毒人群以及格沙屯正常人群分别作为砷中毒组和对照组,实时荧光定量PCR检测各组人群Gadd45β和Gadd45γ基因mRNA表达水平。同时,分别以不同剂量亚砷酸钠、不同时间处理MIHA细胞,流式细胞术测定细胞周期改变情况,实时荧光定量PCR和免疫印迹法分别检测Gadd45β和Gadd45γ基因mRNA表达水平和蛋白表达情况。在上述实验基础上,针对Gadd45β和Gadd45γ基因分别设计的siRNA作用于染砷的MIHA细胞,反向验证Gadd45β和Gadd45γ基因在砷致细胞周期改变过程中的影响。统计学分析采用独立样本t检验比较两组间差异,采用单因素方差比较多组间差异。结果 人群实验研究发现,与对照组相比,砷中毒患者Gadd45β和Gadd45γ基因mRNA表达水平升高(t = 2.576,P = 0.011;t = 2.312,P = 0.022);MIHA细胞中,随亚砷酸钠染毒剂量、染毒时间增加,细胞G2/M期比例明显升高(F剂量 = 340.136,P<0.001;F时间 = 49.194,P<0.001);在相对较低亚砷酸钠浓度(低于20 μmol/L)、一定时间内(低于48 h)Gadd45β和Gadd45γ基因mRNA和蛋白表达水平随染砷剂量、染砷时间升高而升高,超过该浓度范围和作用时间后,出现表达下降的现象(Gadd45β:F剂量-蛋白 = 37.568,P<0.001;F剂量- mRNA = 9.771,P<0.001;F时间-蛋白 = 61.144,P<0.001;F时间- mRNA = 46.366,P = 0.001;Gadd45γ:F剂量-蛋白 = 12.989,P = 0.001;F剂量- mRNA = 23.613,P<0.001;F时间-蛋白 = 27.425,P<0.001;F时间- mRNA = 37.969,P<0.001)。转染siRNA分别下调Gadd45β和Gadd45γ的表达后,细胞周期都出现G2/M期比例下调(t = 3.053,P = 0.038;t = 14.47,P<0.001)。结论 砷致Gadd45β和Gadd45γ基因表达水平升高在其诱导MIHA细胞出现G2/M期阻滞过程中发挥重要作用。  相似文献   
68.
目的 提取、鉴定嗜黏蛋白阿克曼菌(Akkermansia muciniphila, AKK)的脂多糖(lipopolysaccharide,LPS),初步探讨AKK的LPS对小鼠巨噬细胞的影响。 方法 试剂盒法提取AKK的LPS并纯化,ELISA法定量;BCA法、紫外分光光度法、SDS - PAGE和银染鉴定提取的LPS的纯度和结构;鲎试剂法检测LPS活性。体外培养小鼠巨噬细胞RAW 264.7,分为正常对照组、大肠杆菌(Escherichia coli,E.coli) LPS组和AKK LPS组。经LPS作用后,CCK - 8法检测细胞活性;RT - qPCR测定NF - κB、IL - 1β、IL - 6、TNF - α的mRNA表达水平。 结果 纯化的细菌LPS平均产率为7.14%,蛋白、核酸含量分别为0.005 6‰和2.12%;银染结果显示AKK的LPS条带分布与E.coli的LPS不同;鲎试剂测定其活性为7.10×107 EU/ml;部分干预浓度下,AKK LPS干预组细胞存活率低于E.coli LPS组;刺激6 h、12 h、24 h后,与正常对照组相比,AKK LPS干预组细胞内NF - κB的mRNA表达水平在干预6 h后显著上调,差异具有统计学意义(Z = - 3.606,P = 0.001);两种LPS干预组的IL - 1β、TNF - α、IL - 6 的mRNA表达水平在各时间点均高于对照组。 结论 提取的AKK的LPS纯度较高,生物活性良好; AKK 的LPS干预小鼠巨噬细胞,上调相关炎症因子IL - 1β、IL - 6、TNF - α及早期核转录因子NF - κB的转录表达。  相似文献   
69.
目的通过比较卵巢子宫内膜异位囊肿(巧克力囊肿)患者异位囊壁、子宫在位内膜和其他卵巢良性肿瘤患者子宫内膜的组织学特点及分子生物学特征,探究TGF-β1、Smads在子宫内膜异位症(EMs)患者的表达和意义。方法募集行腹腔镜或宫腹腔镜联合术的巧克力囊肿患者,取其卵巢异位症囊壁组织作为卵巢异位症囊壁组,留取其子宫内膜组织作为子宫在位内膜组;同期行宫腹腔镜联合术的其它卵巢良性肿瘤患者,取其子宫内膜组织作为子宫内膜对照组。采用Masson染色、免疫组织化学法分别检测三种组织中纤维化形成和TGF-β1、Smads的表达情况。结果(1)Masson染色显示,卵巢异位症囊壁组可见大量的纤维化沉积,子宫在位内膜组、子宫内膜对照组均未见明显纤维化蓝染。(2)卵巢异位症囊壁组TGF-β1、p-Smad2/3表达水平分别为(0.039±0.024)和(0.035±0.014)均高于子宫内膜对照组(0.018±0.012和0.023±0.004),差异有统计学意义(P<0.05);子宫在位内膜组p-Smad2/3表达水平(0.034±0.011)高于子宫内膜对照组(0.023±0.004)(P<0.05);卵巢异位症囊壁组Smad7的表达水平(0.006±0.003)低于子宫在位内膜组(0.019±0.011)和子宫内膜对照组(0.041±0.023),差异有统计学意义(P<0.01);子宫在位内膜组Smad7的表达含量较子宫内膜对照组低(P<0.01)。结论TGF-β1、p-Smad2/3在子宫内膜异位症中存在高表达,可能通过促进纤维母细胞增生、胶原蛋白的沉积导致异位病灶纤维化的形成,而Smad7作为抑制因子,在EMs中表达降低,对Smads介导的TGF-β1致纤维化的抑制作用减弱,也促使了子宫内膜异位症纤维化的进展。  相似文献   
70.
目的 :研究腺梗豨莶萜二醇酸降压及对血液流变学影响。方法 :采用血流动力学方法 ,观察腺梗莶萜二醇酸对家兔的降压作用、心率减慢作用及其对全血及血浆粘度的影响。结果 :腺梗莶萜二醇酸十二指肠给药能使家兔 ABP、L VSP、± dp/ dtmax、HR、DBP都呈下降趋势 ,降压速度与剂量呈正性相关 ,并使家兔全血粘度 (低切、中切、高切 )下降。结论 :腺梗莶萜二醇酸是腺梗莶降压的有效成分 ,使全血粘度降低 ,具有抑制血栓形成的作用。  相似文献   
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