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971.
目的探讨细胞毒性T淋巴细胞相关抗原4融合蛋白(CTLA-4Ig)对活动期狼疮肾炎(LN)患者外周血单个核细胞(PBMC)细胞表面B7-1(CD80)和B7-2(CD86)表达的影响及其对抗双链DNA(dsDNA)抗体和免疫球蛋白产生的影响。方法将18例活动期LN患者的抗凝血标本随机分为LN的CTLA-4Ig处理组(LN-T组9例)和普通培养组(LN-NC组9例)。另以14例正常人的抗凝血标本为对照,随机分为正常人的CTLA-4Ig处理组(NC-T组7例)和普通培养组(NC-NC组7例)。用密度梯度离心法分离PBMC。处理组加入CTLA-4Ig(10ng/L)、普通培养组加入等量普通培养基37℃孵育72h后,采用流式细胞仪技术检测PBMC细胞表面B7-1和B7-2分子的表达;ELISA法检测孵育液中抗dsDNA抗体、IgG及IgM水平。结果活动期LN患者CTLA-4Ig处理组与普通培养组比较,PB-MC表面B7-2分子表达明显下降(P<0.01);B7-1分子表达无显著变化(P>0.05);孵育液中抗dsD-NA抗体、IgG及IgM的生成均明显减少(P<0.01)。而正常人的两组间各指标差异均无统计学意义(P>0.05)。结论CTLA-4Ig可抑制活动期LN患者的PBMC表面B7-2分子的表达,并可减少其抗dsDNA抗体、IgG及IgM的分泌。  相似文献   
972.
目的建立分泌抗EPF(Early pregnancy factor,早孕因子)单克隆抗体的杂交瘤细胞株,纯化单抗并鉴定.方法用本实验室已纯化的早孕和肿瘤源性EPF作为抗原刺激Balb/c小鼠,用免疫后的小鼠脾细胞与同系小鼠骨髓瘤细胞(NS-1)融合,经4次克隆化,获得可稳定分泌抗EPF单克隆抗体的细胞株,注入Balb/c小鼠腹腔制备腹水型单抗,Protein-A亲和层析纯化,SDS电泳和Western-blot等方法分析纯化结果.结果融合后获得一株稳定分泌抗EPF抗体的细胞株(C3D11),克隆化后,获得稳定分泌抗EPF单克隆抗体的细胞株,将增殖后的细胞注射Balb/c小鼠腹腔获得腹水型单抗,以亲和层析法纯化,SDS-PAGE分析显示纯化后去掉了大部分杂蛋白,免疫印迹分析抗体纯度较高,与抗原匹配性良好.结论本研究制备的EPF单克隆抗体为特异性抗EPF抗体.  相似文献   
973.
Complete porcine CD3ζ-chain cDNA sequence was obtained for the first time, and its genomic nucleotide sequence was investigated from exon 2 down to CD3η-chain exon 8. The sequence of porcine CD3ζ-chain showed homologous amino acid sequence with human and murine counterparts, in contrast to CD3η-chain exon 8 with diversity among animals previously investigated. CD3η-chain peptide is an alternative splice form of CD3ζ-chain exon 7 splicing to CD3η-chain exon 8 instead of CD3ζ-chain exon 8. The genomic sequences revealed that the splice acceptor sequences of CD3η-chain exon 8 of all animals investigated to be completely uniform. Further, CD3η-chain exon 8 amino acid sequences retained the unique characters of having high proline (Pro) and positively charged amino acid content except for rats and mice. Although the biological role of CD3η-chain remains to be enigmatic, these evidences suggests the evolutional pressure to maintain its sequence.  相似文献   
974.
Nuclear translocation of β-catenin has been correlated with epidermal growth factor receptor (EGFR) overexpression/activation in nonsmall cell lung cancer. Less is known on β-catenin transactivation in high-grade pulmonary neuroendocrine tumors and on the status of β-catenin activating EGFR and human epidermal growth factor receptor 2 (HER-2) or β-catenin target genes cyclin D1 and matrix metalloproteinase-7 (MMP-7). β-catenin immunoreactivity was evaluated in 51 large-cell neuroendocrine carcinomas (LCNEC) and 45 small-cell lung carcinomas (SCLC). Nineteen cases were assessed for β-catenin gene exon 3 mutations, expression of MMP-7, and expression/gene amplification of EGFR, HER-2, and cyclin D1. β-catenin was expressed in all 96 high-grade neuroendocrine tumors, the vast majority (94%) showing >50% immunopositive cells. A disarrayed immunoreactivity, however, was commonly encountered consisting in variably altered membrane-associated patterns of staining along with progressive accumulation of cytoplasmic immunoreactivity. In LCNEC, but not in SCLC, the disarrayed patterns correlated with EGFR and HER-2 protein expression. β-catenin nuclear accumulation was found in nine tumors, including seven LCNEC and two SCLC, and was always associated with disarrayed immunoreactivity and increased MMP-7, but not cyclin D1 expression. These cases, however, did not show β-catenin gene mutations or EGFR and HER-2 gene amplification or expression. No association was found between nuclear β-catenin and any clinicopathological variable including patients' survival. The subcellular compartmentalization of β-catenin is profoundly altered in high-grade pulmonary neuroendocrine tumors. A minor subset of these tumors shows β-catenin nuclear accumulation in association with increased expression of MMP-7, but not of cyclin D1, independent of EGFR and HER-2 gene amplification or expression. The authors have no significant financial or other relationship with the manufacturers of any commercial products or commercial services presented in this paper  相似文献   
975.
目的:探讨血浆心钠素(ANP)、脑利钠肽(BNP)、C型利钠肽(CNP)在2型糖尿病血管病变时的变化及其临床意义。方法:应用酶联免疫吸附法(ELISA)测定正常对照组(9例)、2型糖尿病无血管病变组(34例)及2型糖尿病血管病变组(23例)血浆proANP、BNP fragment及NT-proCNP浓度,分析各组间血浆利钠肽水平的变化及相关因素。结果:2型糖尿病血管病变组血浆ANP、BNP明显高于另外2组(P<0.01),而血浆CNP明显降低(P<0.01),2型糖尿病血管病变组各亚组(微血管病变组、大血管病变组及微血管合并大血管病变组)间血浆利钠肽水平无明显差异(P>0.05)。2型糖尿病血管病变组血浆ANP与BNP间存在显著正相关(r=0.309, P<0.05),ANP与CNP(r=-0.374, P<0.05)以及BNP与CNP(r=-0.653, P<0.01)间存在显著负相关。结论:血浆ANP、BNP及CNP的联合检测可以作为简便、价廉、可靠的糖尿病血管病变的筛选指标。  相似文献   
976.
目的 研究携带肝细胞生长因子基因的重组质粒(pUDKH)经肌肉注射给药后在大鼠体内的组织分布及其与大鼠基因组DNA的整合情况。 方法 二级Wistar大鼠雌雄各20只,按体重和取样时间的不同随机分为12h、24h、3d、7d、14d、21d的各实验组(给予pUDKH,2.0mg/kg)和注射后3d取样的对照组(给予PBS,200ul/只),依次将各组大鼠摘眼球取血后脱臼处死,按脑、心、肺、胸腺、肝、肠系膜淋巴结(MLN)、脾、肾、生殖腺、左腿肌肉、右腿肌肉的顺序取样。经典酚/氯仿抽提法提取各组织总DNA,应用紫外分光光度计测定其浓度和纯度,PCR方法检测其中的D肌动蛋白基因;巢式PCR检测各组织总DNA中pUDKH的分布情况;ApnL I酶切分离pUDKH分布阳性各组织中的pUDKHDNA和基因组DNA,巢式PCR检测pUDKHDNA与基因组DNA的整合情况。 结果 各组织总DNA浓度与纯度均符合实验需要,并适于采用PCR或巢式PCR方法进行体内组织分布及基因组DNA整合情况检测。巢式PCR检测显示,在各时间点的右腿肌肉与外周血、注射后3和7d的肝脏、3和14d的生殖腺、7d的胸腺、7和14d的MLN与左腿肌肉等组织中pUDKH分布均呈阳性,而在各时间点的脑、心、肺、脾、肾等组织中pUDKH分布均呈阴性。pUDKH分布阳性的各组织中均未检测到pUDKHDNA与基因组DNA的整合。 结论 pUDKH经肌肉注射给药后,在各时间点大鼠体内各组织中呈现不同的分布谱。在pUDKH分布阳性的各组织中,pUDKHDNA与基因组DNA发生随机整合的概率较低。  相似文献   
977.
目的 研究鼠巨细胞病毒(MCMV)感染对体外培养神经干细胞(NSCs)分化及分化基因表达的影响,探讨CMV先天感染致神经损伤的机制.方法 体外分离培养和鉴定BALB/c胎鼠NSCs并检测其分化潜能,用感染复数(MOI)为5、1和0.1的MCMV Smith毒株感染NSCs并进行分化培养,倒置显微镜下观察细胞形态学改变,流式细胞术检测分化细胞比率,免疫荧光法观察NSCs及其分化细胞标记物Nestin、胶质纤维酸性蛋白(GFAP)和神经元特异性烯醇化酶(NSE)表达的变化,采用MCMV早期抗原(EA)示踪感染过程(MOI=1),real-time RT-PCR检测分化早期NSCs Wnt信号途径关键分化基因Wnt-3和Wnt-Ta mRNA水平的动态变化.结果 体外培养的NSCs呈球样生长,神经干细胞特异性标记Nestin表达阳性,并可进一步诱导分化为NF-200阳性的神经元和GFAP阳性的星形胶质细胞;分化培养后,感染组NSCs不能贴壁分化生长并逐渐出现肿胀,细胞Nestin表达下调缓慢并显著高于正常对照组,而GFAP和NSE表达显著低于正常对照组(P<0.05),可检测到MCMV EA的阳性表达;分化培养3-9 d,感染组Nestin阳性细胞比率显著高于正常对照组,GFAP和NSE阳性细胞比率显著低于正常对照组(P<0.05);感染组Wnt-3 mRNA水平在分化培养后第1~2天显著低于正常对照组(P<0.05),感染组Wnto-7a mRNA水平在第0.5~2天明显低于正常对照组(P<0.05);感染组和正常对照组的差异随病毒MOI的增加而更加明显.结论 MCMV感染可明显抑制NSCs向神经元和星形胶质细胞方向分化,导致分化细胞比率减少;下调或干扰NSCs wnt信号途径分化基因wnt-3和Wnt-7a的表达;抑制NSCs分化及其分化基因表达的效应与MOI大小存在一定量效依赖关系;MCMV可能通过抑制NSCs分化基因的表达来抑制其分化,这可能是CMV先天感染致脑发育异常的重要机制之一.  相似文献   
978.
人表皮生长因子—PE40重组毒素的构建   总被引:8,自引:0,他引:8  
用PCR方法扩增人表皮生长因子(EGF)片段,并将其与绿脓杆菌外毒素(PE40)片段分别插入质粒pET-17b中,经酶切分析和PCR检测证明成功地构建了表达质粒pEGF40,旨在表达一种对癌细胞有特异杀伤作用的融合蛋白,以探索其作为新型导向药物的可能性。  相似文献   
979.
Over the last two decades, nitric oxide (NO) has been established as a novel mediator of biological processes, ranging from vascular control to long-term memory, from tissue inflammation to penile erection. This paper reviews recent research which shows that NO and its derivatives also are synthesized within skeletal muscle and that NO derivatives influence various aspects of muscle function. Individual muscle fibres express one or both of the constitutive NO synthase (NOS) isoforms. Type I (neuronal) NOS is localized to the sarcolemma of fast fibres; type III (endothelial) NOS is associated with mitochondria. Isolated skeletal muscle produces NO at low rates under resting conditions and at higher rates during repetitive contraction. NO appears to mediate cell–cell interactions in muscle, including vasodilation and inhibition of leucocyte adhesion. NO also acts directly on muscle fibres to alter cell function. Muscle metabolism appears to be NO-sensitive at several sites, including glucose uptake, glycolysis, mitochondrial oxygen consumption and creatine kinase activity. NO also modulates muscle contraction, inhibiting force output by altering excitation–contraction coupling. The mechanisms of NO action are likely to include direct effects on redox-sensitive regulatory proteins, interaction with endogenous reactive oxygen species, and activation of second messengers such as cyclic guanosine monophosphate (cGMP). In conclusion, research published over the past few years makes it clear that skeletal muscle produces NO and that endogenous NO modulates muscle function. Much remains to be learned, however, about the physiological importance of NO actions and about their underlying mechanisms.  相似文献   
980.
PROBLEM and METHOD: Early pregnancy factor (EPF), an Immunosuppressive substance, which appears in pregnant women's sera 48 h after fertilization, is a kind of pregnancy-specific protein. To determine whether the EPF activity could be a super early indicator of pregnancy, we used rosette inhibition assay to detect EPF activity in the sera, collected from 70 women 2–7 days after ovulation intending to conceive monitored by ultrasonography. Simultaneously we selected 40 non-pregnant sera and 12 early-pregnant sera as negative control and positive control, respectively. RESULTS: The results of this study demonstrated that EPF activity is detected in 35 women's sera out of 70 women within 2–7 days after ovulation, and 28 women out of the 35 were pregnant, which was known by follow-up, and 7 were not pregnant, possibly due to either false positive results or embryo loss because of preimplantation failure, thus causing no pregnancy. The other 35 out of 70 had no EPF activity and 34 of them were not pregnant, which was known by follow-up, but one case became pregnant, which was false negative result. Our study showed that diagnosis of the super early pregnancy could be made by detecting EPF activity in maternal serum within the time of preimplantation. The accuracy of pregnancy diagnosis by this method is 88.6%, with a false negative rate of 3.4% and a false positive rate of 17.1%. The β-HCG level was measured from the above 70 women's sera in order to contrast EPF activity. All of the sera collected 2–6 days following ovulation indicated that there were lower β-HCG values in very early pregnancy (≥a5 mIU/ml). On the seventh day after ovulation, EPF activity was detected in 11 out of 15 sera with only 2 of them with a b-HCG level that reached or slightly surpassed that of the early pregnancy diagnosis (5 mIU/ml and 5.4 mIU/ml, respectively). This demonstrated that β-HCG is not the earliest signal of pregnancy; otherwise the EPF activity is one that appears 2–6 days earlier than β-HCG appears. We measured the progesterone level of the 48 sera from the 70 collected above within 2–7 days postovulation and found most of them reached the level of progesterone in the luteal phase (7.5–98.3 nmol/L). This indicated that ovulation had taken place in these women, which was in accordance with observations by ultrasonography. CONCLUSIONS: Our study showed that diagnosis (of 88.6%) of super early pregnancy could be made with an accuracy of 88.6% by detecting EPF activity in maternal serum within 2-days after ovulation. This offers a basis for pregnancy diagnosis for the women who attempt to terminate their pregnancy safely or who conceive unexpectedly, and it contributes to family-planning.  相似文献   
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