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101.
Dendritic cells (DC) are crucial gatekeepers in regulating immunity. Whereas mature immunostimulatory myeloid DC (DC(ims)) potently promote immune responses, IL-10-induced myeloid DC (DC-IL-10) counteract T cell activation. To elucidate the molecular repertoire by which DC-IL-10 secure reduced T cell activation, comparative gene expression profiling was done using Affymetrix U133A microarrays. Among the genes overexpressed in DC-IL-10, eight immunoreceptor tyrosine-based inhibitory motif (ITIM)-containing inhibitory molecules (ILT2, ILT3, ILT4, ILT5, DCIR, PILRA, FcgammaRIIB, SLAM) were found. Phenotypic analysis of DC-IL-10 defined an ILT(high) DC subset further characterized by expression of CD14, TLR2, DC-SIGN, and CD123 and the lack of lymphocyte, monocyte/macrophage, and plasmacytoid DC markers such as CD3, CD8, and CD68. A unique feature of the ILT(high) DC subset was expression of the novel DC marker BDCA3, which was not detected on monocytes, immature DC, DC(ims), or ILT(low) DC-IL-10. While the allogeneic T cell proliferation induced by the entire DC-IL-10 population was approximately 30% of that stimulated by DC(ims), allogeneic MLR responses driven by the ILT(high) DC subset were reduced to 8% of the allostimulatory capacity of DC(ims), although secretion of the inhibitory cytokine IL-10 and other Th1/Th2-associated cytokines was similar in these cells.  相似文献   
102.
Summary The distribution of somatostatin (SRIF)-immunoreactive neurons in the visual cortical areas 17, 18 and 18a of Wistar rats from birth to adulthood was followed in both normal and dark-reared animals. The SRIF neurons show difference in distribution amongst the three cortical areas studied as early as the first postnatal week. Area 17 was distinguished by fewer SRIF cells in the upper layers (I–III), which results in a lower overall density. The SRIF neurons in all areas appeared to increase in numbers up to about 3 weeks and then decline dramatically to adult levels, which were 14–19% of the peak levels. Although this decline was still obvious, it moderated to 25–31% in dark-reared animals. The greatest effect was seen in area 18 where, at 60 days of age, there were twice as many SRIF cells in darkreared as in normal controls. It is suggested that, under conditions of dark rearing, the overall pattern of development of SRIF neurons, being uninfluenced by extrinsic factors, reveals the cells' genetic potential.  相似文献   
103.
HLA-DRB1*07与慢性乙肝患者Th1/Th2因子表达水平的相关性   总被引:6,自引:0,他引:6  
目的 :探讨广东地区汉族慢性乙型肝炎患者HLA DRB1 0 7与Th1 Th2因子表达水平的相关性。方法 :收集 12 0例广东地区汉族慢性乙肝患者新鲜抗凝血各 8ml,通过序列特异性引物套式PCR(PCR SSP)方法进行HLA DRB1 0 7检测 ,并同时用双抗体夹心法检测患者治疗前后外周血CD4 +T细胞分泌IFN γ、IL 2、IL 10和IL 4的水平。结果 :12 0例慢性乙肝患者HLA DRB1 0 7携带者 31例 ,携带率为 2 5 8% ,明显高于广东地区汉族人群的平均携带率 7 84 % ;HLA DRB1 0 7阳性患者IFN γ平均表达水平为 (1132 0 4± 75 36 )pg ml,IL 2平均表达水平为 (1184 0 6± 81 4 2 )pg ml,IL 4平均表达水平为 (876 79± 4 7 5 3)pg ml,IL 10平均表达水平为 (817 4 8± 2 4 4 0 )pg ml ;HLA DRB1 0 7阴性患者IFN γ平均表达水平为 (12 32 10± 198 13)pg ml,IL 2平均表达水平为 (12 0 8 17± 116 12 )pg ml,IL 4平均表达水平为 (6 81 99± 6 1 5 9)pg ml,IL 10平均表达水平为 (6 38 84± 76 17)pg ml。HLA DRB1 0 7阳性患者IL 4、IL 10表达水平高于阴性患者 (P <0 0 5 ) ,而IFN γ、IL 2表达水平与阴性患者差异无统计学意义 (P >0 0 5 )。结论 :HLA DRB1 0 7(+)慢性乙肝患者Th2因子表达水平高于HLA DRB1 0 7(- )慢性乙肝患者。  相似文献   
104.
目的 :探讨严重烧伤患者血清IL 18、sFas和sFasL水平间的变化及其与病情的关系。方法 :选择烧伤总面积(TBSA)≥ 30 %的严重烧伤患者 30例 ,其中死亡 3例 ;正常对照组 4 5例。采用ELISA法对不同时相点 (伤后 1、3、5、7、14、2 1、2 8和 35天 )患者血中IL 18、sFas和sFasL水平进行检测。结果 :与正常对照组比较 ,患者血清IL 18、sFas和sFasL水平均呈显著性上升 (P <0 0 1~ 0 0 5 ) ,并分别持续至伤后 2 8,2 1和 2 1天 ;感染组患者血清IL 18、sFas和sFasL水平均显著地高于非感染组 (P <0 0 1~ 0 0 5 ) ;死亡组患者血清IL 18水平下降 ,而sFasL水平则升高。患者血清IL 18和sFasL水平与烧伤面积相关 ;患者血清IL 18、sFas和sFasL之间也呈显著正相关 (P <0 0 1)。结论 :患者血清IL 18、sFas和sFasL水平与烧伤严重程度及伤后感染密切相关 ,在烧伤后免疫功能及凋亡调控中可能起一定作用。  相似文献   
105.
目的 利用Bac-to-Bac杆状病毒表达系统表达鼠IL-4受体拮抗体 (mIL-4RA)蛋白.方法 PCR方法扩增小鼠IL-4 C118截断型基因,定向克隆入转移质粒pFastBacHTB中,转化感受态DH10Bac细胞,在DH10Bac细胞内重组pFastBacHTB与杆粒发生转座.筛选阳性克隆,提取重组杆粒,转染sf9昆虫细胞株,获取完整重组杆状病毒.反复感染sf9细胞,扩增病毒同时表达目的 蛋白;用ELISA方法进行蛋白鉴定并初步定量.结果 经核苷酸序列测定及PCR方法,鉴定成功获得含mIL-4RA基因的重组杆粒;通过杆粒转染后sf9细胞所表现出来的细胞病变,推断成功转染并获得重组杆状病毒;最后ELISA方法初步定量sf9细胞培养上清中mIL-4RA蛋白表达量为(1.15±0.12) ng/mL.结论 本研究利用Bac-to-Bac杆状病毒表达系统成功表达mIL-4RA蛋白,为进一步研究其生物学活性及功能奠定了实验基础,同时亦为其他蛋白质的真核表达提供了方法学的参考.  相似文献   
106.
Dendritic cells (DC) not only initiate T cell responses, but are also involved in the induction of tolerance. The functional properties of DC are strictly dependent on their state of maturation. It has been shown that immature DC can induce immune tolerance and prolong allograft survival. Interleukin-10 (IL-10) is an important immunosuppressive cytokine which inhibits maturation and function of DC. In order to improve the tolerogenicity of DC, we and others showed that adenovirus vectors can effectively mediate IL-10 genetic modification of DC, and IL-10 genetic modification can inhibit MHC II, B7.2, and CD40 expression, IL-12 secretion and the T cell stimulatory capacity of DC. The primary aim of this study is to examine the in vivo effects of this approach on allograft survival in a murine cardiac allograft transplantation model. To our surprise, we observed that infusion of immature DC genetically modified to express IL-10 (DC-IL-10) via the tail vein could not prolong allograft survival in the recipients, but shortened their survival. More interestingly, portal venous infusion of DC-IL-10 markedly prolonged allograft survival. The diverse effects of DC-IL-10 infusion through different routes may be due to the different immune responses to alloantigens in recipients that received DC-IL-10 via either the portal or the tail vein. Decreased cytotoxicity, polarization of Th2 response, poor T cell stimulating activity of liver DC and enhanced incidence of donor DC in the recipients may contribute to the more efficient prolongation of allograft survival observed after portal venous infusion of DC-IL-10. These results suggest that portal venous infusion may be an effective approach for immature DC to induce immune tolerance or hyporesponsiveness against donor antigens, and prolong allograft survival.Abbreviations APC Antigen-presenting cells - CTL Cytotoxic T lymphocytes - DC Dendritic cells - DC-IL-10 IL-10 gene-modified immature dendritic cells - iDC Immature dendritic cells - IL-10 Interleukin-10 - MLR Mixed leukocyte reaction - MOI Multiplicity of infection  相似文献   
107.
目的:获取rhIL-18原核表达产物并研究其活性。方法:用本室构建的含基因重组表达载体PBV220-IL-18的大肠杆菌DHSot,经42℃热诱导表达和包涵体提取纯化后获取rhIL-18蛋白;采用ELISA试剂盒检测rhIL-18刺激PBMC分泌IFN-γ的活性及MTT法检测其对NK细胞杀伤K562细胞自然杀伤活性;同时用荷瘤小鼠模型检测其体内抗瘤功能。结果:诱导含重组表达载体PBV220-IL-18的大肠杆菌D145ct后,蛋白电泳显示出一条相对分子量(Mτ)为18000的蛋白条带;10μg rhIL-18蛋白体外刺激PBMC后,其分泌IFN-γ的能力与对照组相比提高了8倍,细胞毒性提高3倍;同时rhIL-18蛋白能明显抑制肿瘤生长和延长荷瘤鼠生存期。结论:获得了有免疫调节功能和抗肿瘤活性的rhIL-18蛋白。为今后IL-18重组产物的研制和开展肿瘤的生物治疗提供了实验依据。  相似文献   
108.
IL-1, IL-18, and IL-33 families of cytokines   总被引:4,自引:0,他引:4  
Summary: The interleukin-1 (IL-1), IL-18, and IL-33 families of cytokines are related by mechanism of origin, receptor structure, and signal transduction pathways utilized. All three cytokines are synthesized as precursor molecules and cleaved by the enzyme caspase-1 before or during release from the cell. The NALP-3 inflammasome is of crucial importance in generating active caspase-1. The IL-1 family contains two agonists, IL-1α and IL-1β, a specific inhibitor, IL-1 receptor antagonist (IL-1Ra), and two receptors, the biologically active type IL-1R and inactive type II IL-1R. Both IL-1RI and IL-33R utilize the same interacting accessory protein (IL-1RAcP). The balance between IL-1 and IL-1Ra is important in preventing disease in various organs, and excess production of IL-1 has been implicated in many human diseases. The IL-18 family also contains a specific inhibitor, the IL-18-binding protein (IL-18BP), which binds IL-18 in the fluid phase. The IL-18 receptor is similar to the IL-1 receptor complex, including a single ligand-binding chain and a different interacting accessory protein. IL-18 provides an important link between the innate and adaptive immune responses. Newly described IL-33 binds to the orphan IL-1 family receptor T1/ST2 and stimulates T-helper 2 responses as well as mast cells.  相似文献   
109.
目的 探讨18q21在人胰腺导管腺癌和慢性胰腺炎中杂合性缺失(LOH)的情况及其相关因素.方法 选择18q21上的位点RP11-729G3和RP11-850A17作为目的 片段,选择接近18号染色体着丝粒的位点RP11-621L6作为参照位点,利用细菌人工染色体(BAC)提取、纯化相应位点的DNA,用切口平移法分别标记生物素和地高辛后制成双色探针,应用荧光原位杂交技术(FISH)检测30例胰腺导管腺癌和10例慢性胰腺炎石蜡包埋组织切片中18q21 LOH情况,并收集、整理相应临床病理资料进行相关性分析.结果 30例胰腺导管腺癌中在RP11-729G3位点有25例(83.3%)有LOH,在RP11-850A17位点26例(86.6%)有LOH,其中25例在RP11-729G3和fuP11-850A17两个位点均有LOH,1例仅在RP11-850A17位点有LOH.10例慢性胰腺炎中均未发现18q21 LOH.经统计学分析发现,18q21 LOH在慢性胰腺炎和胰腺导管腺癌中差异有统计学意义(P<0.01),且RP11-729G3和RP11-850A17两个位点LOH有高度相关性(Phj系数=0.877),但和临床病理各因素间未发现明显相关.结论 18q21 LOH在胰腺导管腺癌中属于高频事件,并且位点RP11-729G3和RP11-850A17的LOH有高度相关性,可能在胰腺导管腺癌发生发展中起重要作用.在临床诊断中18q21LOH也能作为较特异的标记辅助诊断.  相似文献   
110.
Monosomy for the short arm of chromosome 18 is one of the most frequent autosomal deletions observed. While most cases result from terminal deletion of 18p, 16% of cases reported were as a result of an unbalanced whole arm translocation resulting in monosomy 18p. The origin and structure of these derivative chromosomes were reported in only a few cases. We report the prenatal diagnosis and characterization of a new case of monosomy 18p as a result of an unbalanced whole arm translocation. Amniocentesis was performed at 15 weeks of gestation on a 34-year-old woman initially referred for advanced maternal age. Holoprosencephaly was identified by ultrasound at the time of amniocentesis. Karyotype analysis showed an unbalanced whole arm translocation between the long arm of one chromosome 18 and the long arm of one chromosome 22, 45,XX,der(18;22)(q10;q10), in all metaphases. In effect, the fetus had monosomy for 18p. Parental karyotypes were normal, suggesting a de novo origin for the der(18;22). Fluorescence in situ hybridization (FISH) analysis was performed with alpha-satellite probes D18Z1 and D14Z1/D22Z1 to identify the origin of the centromere on the der(18;22). Signal was observed with both probes, indicating that the centromere was composed of alpha-satellite DNA from both constituent chromosomes. Genotyping of the fetus and her parents with chromosome 18p STS marker D18S391 showed only the paternal 187 bp allele was present in the fetus, indicating that it was the maternal chromosome 18 involved in the der(18;22). This case and previous reports show that de novo unbalanced whole arm translocations are more likely to retain alpha-satellite sequences from the two chromosomes involved.  相似文献   
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