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1.
目的 探讨溶质载体蛋白(SLC)及其受体趋化因子受体7(CCR7)与I期非小细胞肺癌(NSCLC)淋巴结微转移的相关性。方法 选取2019年1月~2020年3月于我院就诊的I期NSCLC患者127例为研究对象,按照淋巴结微转移情况分为对照组92例和转移组35例,所有患者入院后均通过根治术切除病灶,通过免疫组化方式检测病灶中SLC7A11及CCR7含量,并收集患者临床资料、实验室检查资料及影像学检查资料。通过Logistic回归分析评价SLC7A11及CCR7与淋巴结微转移之间的关系。最后通过建立ROC曲线分析两者及其联合检测对NSCLC患者微淋巴结转移的预测价值。结果 两组患者SLC7A11及CCR7表达水平存在显著差异(P<0.05)。转移组患者病灶直径、支气管受累及TLG显著高于对照组(P<0.05)。病灶直径(OR=49.254,95%CI=11.062~507.604)是影响NSCLC淋巴结微转移的独立危险因素(P<0.05)。SLC7A11(OR=8.622)及CCR7(OR=8.709)表达水平是影响NSCLC淋巴结微转移的独立因素(P<0.05)。SLC7A11、CCR7及联合诊断对NSCLC淋巴结微转移具有较好的检测价值(均P<0.05)。联合检测特异度显著高于 SLC7A11及CCR7单独检测(2=7.292,15.125;均P<0.01)。结论 SLC家族的中SLC7A11及其受体CCR7与NSCLC患者微淋巴结转移显著相关。  相似文献   
2.
目的分析热射病患者外周血单个核细胞转录组测序生物信息学结果,寻找影响热射病预后的关键基因。方法选取2019-06-01~2020-08-30空军军医大学附属西京医院急诊科收治的热射病患者,按照预后分为生存组和死亡组。随机数字法在两组中分别选取患者进行外周血单个核细胞转录组测序,生物信息学分析寻找差异基因;RT-PCR验证筛选出的差异基因在生存组和死亡组中的表达。结果29例诊断为热射病患者入选,按照预后分为生存组和死亡组,其中生存组18例,死亡组11例。随机数字法选取6例生存患者和4例死亡患者,外周血单个核细胞进行转录组测序,两组患者有693个基因表达有明显差异,通过生物信息学分析筛选出趋化因子(C-C基元)配体5(CCL5)、基质金属蛋白酶8(MMP8)、MMP9基因可能与预后相关。将两组外周血单个核细胞的目标基因表达情况通过RT-PCR法表达检测,与生存组比较,死亡组MMP8基因(P=0.8955)和MMP9基因(P=0.0597)表达无明显变化,CCL5基因表达明显上升(t=7.056,P<0.05)。结论CCL5基因可能是影响热射病预后的关键基因,需要进一步深入研究。  相似文献   
3.
4.
目的探讨血清趋化因子检测在肺癌早期诊断中的应用价值。方法采用回顾性总结研究方法,选择肺癌患者72例(肺癌组)、肺炎患者72例(肺炎组)与健康人72例(对照组),检测3组人群的白细胞计数,检测血清趋化因子MIP-3α、IL-8、Fractalkine水平,随访记录患者的预后,判断诊断价值。结果肺癌组与肺炎组的外周白细胞计数均显著低于对照组(P<0.05),但肺癌组与肺炎组对比差异无统计学意义(P>0.05)。肺癌组与肺炎组的血清MIP-3α、IL-8、Fractalkine水平都高于对照组(P<0.05),肺癌组高于肺炎组(P<0.05)。随访至2018年9月,肺癌组中患者死亡6例,存活66例,死亡率为8.3%。多因素logistic回归分析淋巴结转移、临床分期、组织学分化、MIP-3α、IL-8、Fractalkine为影响患者预后死亡的主要独立危险因素(P<0.05)。结论MIP-3α、IL-8、Fractalkine等趋化因子联合现有的肿瘤标志物,可用于诊断早期肺癌与预测预后。  相似文献   
5.

Background

Successful vaccinations rely on antibody responses. Chemokine receptors play an important role in B cell homing to differentiation niches. We assessed CXCR4, CXCR5 and CCR6 expression on B cells during HIV-1 infection and relate it to antibody responses against a HBV vaccine.

Methods

Blood was obtained from 54 healthy controls and 38 ART-treated HIV-1 infected children, aviremic (n?=?25) or viremic (n?=?13). Frequency of naïve and memory B cell subsets was studied by immunostaining. Homing capacity of blood B cells to lymphoid and inflamed tissues was evaluated through CXCR4, CXCR5 and CCR6 expression. Plasma CXCL12 and CXCL13 levels and antibody titers to HBV antigen were determined by ELISA.

Results

The frequency of naïve and resting memory (RM) B cells in ART treated children was comparable to control subjects. Profound defects in the homing phenotypes of naïve and memory B cells were identified, with lower CXCR4 and CXCR5 expression. Increased CXCL13 levels were observed in infected children, inversely correlating to CXCR5 expressing B cell subpopulations. Antibody titers to HBV vaccine correlated with frequency of resting and switched memory B cells in HIV-1 infected children.

Conclusions

Homing defects of B cells to germinal center may underlie impaired vaccine responses during HIV-1 infection.  相似文献   
6.
The innate immune system can recognize non-self, danger signals, and pathogen associated molecular patterns and provides a first line of antimicrobial host defense. Therefore, it plays an instructive role and is pretty important in vertebrates. In innate immune responses, CXCRs act as the main receptors of CXC chemokines and play a vital role in host defense and inflammation. In present study, we cloned two cDNA molecules of CXCR1 and CXCR4 in Miichthys miiuy (miiuy croaker). In these two genes, we found the most highly conserved DRY motif in the second intracellular loop adjacent to the third transmembrane domain. The expressions of CXCR1 and CXCR4 showed that they were ubiquitously expressed in ten normal tissues. After infection with Vibrio anguillarum and Vibrio harveyi, the expressions of CXCRs in the immune tissues were significantly regulated in most of tissues except that of CXCR1 in the kidney after V. harveyi injection. Evolutionary analysis showed that only the ancestral lineages of CXCR4 in amphibians underwent positive selection, indicating that the ancestors of amphibians boarded the land and had to further evolve to adapt to terrestrial environments. Multiple ML methods were implemented to detect the robust positively selected candidates for sites. In total, we detected 12 and 3 positively selected sites in the subsets of current mammal and fish CXCR1 genes, and only one site under positive selection was found in mammalian CXCR4 subsets. These positively selected sites were mainly located in the extracellular domains of CXCRs. The sliding window analysis and evolution test tended to favor positive selection acting on the N-terminal domain of CXCR1, which was the critical region for ligand/receptor signaling for neutrophils and receptor–ligand interaction, indicating that the N-terminal of CXCR1 in mammals underwent more positive selection than that of fish.  相似文献   
7.
目的:探讨趋化因子CXCL12及其受体CXCR4、CXCR7在乳腺癌组织中的表达及临床意义。方法:应用qRT-PCR方法检测35例新鲜乳腺癌组织及癌旁正常乳腺组织中CXCL12及其受体CXCR4、CXCR7的mRNA表达,采用免疫组化检测120例乳腺癌细胞组织石蜡标本中CXCL12及其受体CXCR4、CXCR7的蛋白表达,并分析三者的表达与患者临床特征的关系。结果:qRT-PCR结果显示,CXCL12、CXCR4、CXCR7的mRNA在乳腺癌组织中表达量均明显高于癌旁正常乳腺组织(均P0.05)。免疫组化结果显示,CXCL12、CXCR4、CXCR7蛋白在乳腺癌组织中阳性表达率分别为70.8%(85/120)、65.8%(79/120)和63.3%(76/120),三者在均在伴有淋巴结转移及TNM分期较高的患者乳腺癌组织中表达明显升高(均P0.05)。结论:趋化因子CXCL12及其受体CXCR4、CXCR7的高表达可能与乳腺癌淋巴转移及恶性进展密切相关。  相似文献   
8.
Staphylococcus aureus is the main pathogen associated with septic arthritis. Upon infection, neutrophils are quickly recruited to the joint by different chemoattractants, especially CXCR1/2 binding chemokines. Although their excessive accumulation is associated with intense pain and permanent articular damage, neutrophils have an important function in controlling bacterial burden. This work aimed to study the role of CXCR2 in the control of infection, hypernociception and tissue damage in S. aureus‐induced septic arthritis in mice. The kinetics of neutrophil recruitment correlated with the bacterial load recovered from inflamed joint after intra‐articular injection of S. aureus. Treatment of mice from the start of infection with the non‐competitive antagonist of CXCR1/2, DF2156A, reduced neutrophil accumulation, cytokine production in the tissue, joint hypernociception and articular damage. However, early DF2156A treatment increased the bacterial load locally. CXCR2 was important for neutrophil activation and clearance of bacteria in vitro and in vivo. Start of treatment with DF2156A 3 days after infection prevented increase in bacterial load and reduced the hypernociception in the following days, but did not improve tissue damage. In conclusion, treatment with DF2156A seems be effective in controlling tissue inflammation and dysfunction but its effects are highly dependent on the timing of the treatment start.  相似文献   
9.
Macrophages play a critical role in the establishment of a regulated inflammatory response following tissue injury. Following injury, CCR2+ monocytes are recruited from peripheral blood to wound tissue, and direct the initiation and resolution of inflammation that is essential for tissue repair. In pathologic states where chronic inflammation prevents healing, macrophages fail to transition to a reparative phenotype. Using a murine model of cutaneous wound healing, we found that CCR2‐deficient mice (CCR2?/?) demonstrate significantly impaired wound healing at all time points postinjury. Flow cytometry analysis of wounds from CCR2?/? and WT mice revealed a significant decrease in inflammatory, Ly6CHi recruited monocyte/macrophages in CCR2?/? wounds. We further show that wound macrophage inflammatory cytokine production is decreased in CCR2?/? wounds. Adoptive transfer of mT/mG monocyte/macrophages into CCR2+/+ and CCR2?/? mice demonstrated that labeled cells on days 2 and 4 traveled to wounds in both CCR2+/+ and CCR2?/? mice. Further, adoptive transfer of monocyte/macrophages from WT mice restored normal healing, likely through a restored inflammatory response in the CCR2‐deficient mice. Taken together, these data suggest that CCR2 plays a critical role in the recruitment and inflammatory response following injury, and that wound repair may be therapeutically manipulated through modulation of CCR2.  相似文献   
10.
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