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1.
The Extracellular Vesicle Flow Cytometry Working Group ( http://www.evflowcytometry.org ) is formed by members of the International Society for Extracellular Vesicles (ISEV), the International Society for Advancement of Cytometry (ISAC), and the International Society on Thrombosis and Haemostasis (ISTH). This working group of flow cytometry experts develops guidelines for best practices regarding flow cytometry detection of extracellular vesicles. To improve rigor and standardization, this working group published a framework outlining the minimal information to report about a flow cytometry experiment on extracellular vesicles (MIFlowCyt-EV) in the Journal of Extracellular Vesicles, the ISEV journal, in 2020. In parallel, an article explaining MIFlowCyt-EV was published in Cytometry Part A, one of the ISAC journals, and now will be introduced to the ISTH as an SSC Communication in the Journal of Thrombosis and Haemostasis. The goal of this SSC Communication is to explain why flow cytometry is becoming the instrument of choice to characterize single extracellular vesicles, the obstacles that have been identified and (mostly) overcome by developing procedures to calibrate flow cytometers, and the relevance of reporting minimal information to improve reliability and reproducibility of experiments in which flow cytometers are used for characterization of extracellular vesicles.  相似文献   
2.
目的探讨合体细胞滋养层细胞外囊泡(STB-EV)阻止母体恶性肿瘤侵袭、转移至胎儿的相关机制。 方法选择2015年6月,于四川大学华西第二医院进行剖宫产术分娩的1例妊娠合并宫颈癌(CCP)患者被肿瘤侵犯的胎盘组织为研究对象。宫颈癌细胞系SiHa细胞和人滋养层细胞系HTR-8细胞,均由本院西部妇幼医学研究院-分子与转化医学实验室馈赠。其中,本例CCP患者被肿瘤侵犯的胎盘组织制作组织切片后,于光学显微镜(×400)和电子显微镜(×2 000)下,观察其组织形态学、STB-EV及合体细胞滋养层(STB)旁宫颈癌细胞自噬性死亡情况等;而SiHa细胞与HTR-8细胞培养后,用于Transwell迁移实验与细胞划痕实验。将SiHa与HTR-8细胞共培养,纳入研究组;单独培养的SiHa细胞,纳入对照组。对2组细胞进行Transwell迁移实验及细胞划痕实验,2组Transwell小室穿膜细胞数、细胞迁移率等比较,采用成组t检验。本研究遵循的程序符合2013年新修订的《世界医学协会赫尔辛基宣言》要求。 结果①对本例CCP患者被肿瘤侵犯的胎盘组织制作组织切片后,于光学显微镜(×400)下观察结果显示,与STB相邻宫颈癌细胞自噬性死亡、凋亡和固缩性坏死显著。电子显微镜(×2 000)下观察结果显示,宫颈癌细胞累及胎盘绒毛组织时,STB分泌的STB-EV水平显著高于正常胎盘组织。②2组细胞Transwell迁移实验结果显示,研究组穿膜细胞数为(597.6±87.7)个/视野,显著低于对照组的(1 358.4±203.0)个/视野,并且差异有统计学意义(t=14.490、P<0.001)。③2组细胞划痕实验结果显示,划痕后48 h时,研究组细胞迁移率为(26.6±3.8)%,显著低于对照组的(45.9±3.7)%,并且差异有统计学意义(t=3.122、P=0.035)。 结论STB分泌的STB-EV可能参与母体肿瘤细胞广泛自噬性死亡,从而阻止母体肿瘤细胞侵袭胎盘、影响胎儿发育。  相似文献   
3.
目的探讨中性粒细胞与淋巴细胞比值(neutrophil to lymphocyte ratio,NLR)联合血红蛋白(hemoglobin,Hb)水平预测子宫肌瘤并子宫腺肌症发生的价值。 方法回顾性分析行子宫切除术治疗的子宫良性病变患者167例的临床资料,根据组织病理学诊断结果分为单纯子宫肌瘤(对照组)95例和子宫肌瘤并子宫腺肌症(观察组)72例。检测患者外周血中性粒细胞计数(neutrophil count,NEUT)、淋巴细胞计数(lymphocyte count,LY)、Hb水平等血常规指标,并计算NLR。比较2组临床资料和生化指标。采用多因素Logistics回归分析子宫肌瘤并子宫腺肌症发生的影响因素,绘制受试者工作特征曲线评估外周血NLR、Hb水平对子宫肌瘤并子宫腺肌症发生的预测价值。 结果观察组糖尿病史患者比例、流产史患者比例、血清人附睾蛋白4(human epididymis protein 4,HE4)、糖类抗原125(carbohydrate antigen 125,CA125)含量、外周血NLR高于对照组,外周血LY、Hb水平均低于对照组(P<0.05)。多因素Logistic分析结果显示,血清HE4含量、血清CA125含量、外周血NLR、外周血Hb水平是影响子宫肌瘤并子宫腺肌症发生的危险因素(OR=1.579、5.726、3.669、1.833);NLR、Hb水平、NLR联合Hb水平预测子宫肌瘤并子宫腺肌症发生的曲线下面积(area under the curve,AUC)分别为0.759(95%CI:0.681~0.836)、0.776(95%CI:0.700~0.852)、0.849(95%CI:0.786~0.913);NLR联合Hb水平预测子宫肌瘤并子宫腺肌症发生的AUC大于单独NLR、Hb水平(P<0.05)。 结论外周血NLR、Hb水平是子宫肌瘤并子宫腺肌症发生的危险因素,可以作为子宫肌瘤并子宫腺肌症早期筛查和诊断的参考指标。  相似文献   
4.
摘要:目的 通过检测类风湿关节炎(RA)患者滑膜巨噬细胞胞外诱捕网(METs)形成情况,探讨 METs 在 RA 发病中的作用。 方法 收集 RA 及创伤手术患者的滑膜组织,采用苏木精-伊红(HE)染色检测炎症浸润情况,激光共聚焦显微镜观察巨噬细 胞(F4 / 80+ )的表达、巨噬细胞极化(F4 / 80+CD86+ ,F4 / 80+CD206+ )情况、METs(F4 / 80+ H2A+ )形成水平。 分离滑膜细胞,用蛋 白免疫印迹法检测滑膜细胞中 METs 瓜氨酸化组蛋白 H3(CH3)及肽酰基精氨酸脱亚胺酶 4(PAD4)的水平。 结果 与创伤手 术患者比较,RA 患者滑膜组织炎性浸润程度较重,炎性细胞增多,巨噬细胞总数和Ⅰ型巨噬细胞(M1)比例均显著增多(98± 7.09 vs 10±1.15,0.78±0.022 vs 0.13±0.011,P<0.001),两组间 M2 型巨噬细胞比例差异无统计学意义(0.23±0.019 vs 0.18± 0.012,P>0.05)。 RA 组 METs 形成显著高于对照组(0.65±0.023 vs 0.18±0.012,P<0.001)。 蛋白免疫印迹法显示 RA 患者滑膜 PAD4 和 CH3 水平较创伤手术患者明显增多(0.82±0.018 vs 0.20±0.015,0.83±0.013 vs 0.40±0.012,P<0.001)。 结论 RA 患者 滑膜中巨噬细胞明显增多,且以 M1 型巨噬细胞为主,METs 形成明显增多。  相似文献   
5.
目的探究外周血中性粒细胞与淋巴细胞比值(NLR)、血小板与淋巴细胞比值(PLR)与妊娠期肝内胆汁淤积症(ICP)的相关性。方法回顾性选取2019年8月至2021年8月海南省妇女儿童医学中心收治的97例ICP患者作为ICP组,再按病情分度分为轻度ICP组(n=62)和重度ICP组(n=35);另选取同期健康孕妇为对照组(n=40)。收集所有受试者一般资料及外周血NLR、PLR水平。比较各组采用单因素、Pearson相关系数法及Logistic回归模型分析相关指标与ICP的关系,采用受试者工作特征曲线(ROC)分析NLR对ICP的诊断价值。结果ICP组NLR为4.86±1.65,明显高于对照组(3.61±1.10),且重度ICP组的NLR为5.23±1.26,明显高于轻度ICP组(4.65±1.39),差异均有统计学意义(P<0.05);但对照组、轻度ICP组、重度ICP组的PLR比较差异均无统计学意义(P>0.05)。NLR与血清总胆汁酸(sTBA)呈正相关(r=0.290,P<0.05),PLR与sTBA无明显相关性(P>0.05)。Logistic回归分析显示,平均血小板体积(MPV)(OR=1.241)、NLR(OR=1.902)是ICP发生的独立影响因素(P<0.05)。ROC曲线显示,NLR诊断轻度ICP、重度ICP的曲线下面积(AUC)分别为0.667、0.699(P<0.05)。结论NLR与ICP的发生、发展及病情程度密切相关,可用作ICP诊断和病情评估的潜在指标,指导临床诊疗,而PLR对ICP的诊断和病情程度评估均未显现价值。  相似文献   
6.
《Dental materials》2022,38(2):421-430
ObjectivesTo determine the long-term effect on the stability of dentin-resin interfaces after the addition of polylactide (PLA) capsules containing proanthocyanidin (PAC) to adhesive resin.MethodsSub-micron (SM) and micron (M) size capsules containing PACs were produced using a combination of emulsification and solvent evaporation techniques and characterized. Human dentin surfaces (n = 8) were etched (35% glycolic acid) and primed (15% enriched Vitis vinifera extract solution - VVe), followed by the application of an experimental adhesive containing 0 (control), 1.5 wt% of SM or M PAC-filled PLA capsules light cured for 40 s. A crown was built using commercial composite. After 24 h-immersion (37 °C) in simulated body fluid, specimens were serially sectioned into resin-dentin beams. Microtensile bond strength (TBS), micro-permeability and fracture pattern were assessed immediately and after 1 and 2 years. Data were statistically analyzed using two-way ANOVA and post-hoc test (α = 0.05).ResultsPolydisperse capsules were manufactured with average diameter of 0.36 µm and 1.08 µm for SM and M, respectively. The addition of capsules did not affect TBS (p = 0.889). After 2 years, TBS significantly decreased in SM (p = 0.006), whereas M showed similar initial values (p = 0.291). Overall, less micro-permeability was found in M than the control and SM group (p < 0.001). After 2 years, fractured surfaces from capsule-containing groups failed within the adhesive layer while control fractured at the bottom of the hybrid layer.SignificanceThe addition of PAC-filled PLA microcapsules in a dental adhesive did not affect the bond strength while increased and sustained the protection against micro-permeability in the interface, likely due to release of PACs.  相似文献   
7.
Biliary tract cancer (BTC) is characterized by a desmoplastic extracellular matrix (ECM). We tested the diagnostic and prognostic use of seven circulating biomarkers of ECM remodeling: pro-peptides of type III collagen (PRO-C3), VI (PRO-C6) and XI (PRO-C11), matrix metalloprotease (MMP) degraded type III collagen (C3M) and type IV collagen (C4M) fragments, granzyme B degraded type IV collagen fragments (C4G) and MMP degraded and citrullinated vimentin (VICM) a marker of macrophage activation. The study included 269 patients with all stages of BTC and 49 patients with benign biliary tract diseases. Serum samples from BTC patients were collected before surgery, or before first- or second-line chemotherapy. C3M, C4M, PRO-C3, PRO-C6, PRO-C11 and VICM levels were elevated in patients with BTC compared to patients with benign disease. Receiver operating characteristics curve analyses identified PRO-C3 (area under curve [AUC] = 0.87) as the ECM marker with the best diagnostic performance. The ECM biomarkers correlated with inflammation biomarkers (C-reactive protein [CRP], interleukin-6 [IL-6] and YKL-40) but not with CA19-9. To investigate prognostic performance, patients were split into three cohorts (first-line, second-line and surgery). Elevated ECM biomarker levels were associated with short overall survival (OS), but only pretreatment PRO-C3 and PRO-C6 were associated with OS in both the first-line and second-line settings when adjusting for CA19-9, performance status and stage in a multivariate Cox-regression analyses. Our results indicate that collagen remodeling is increased in patients with BTC and associated with survival. The collagen pro-peptides (PRO-C3 and PRO-C6) could be used as novel biomarkers in these patients.  相似文献   
8.
Collagens are the most abundant proteins in the extracellular matrix. They provide a framework to build organs and tissues and give structural support to make them resistant to mechanical load and forces. Several intra‐ and extracellular modifications are needed to make functional collagen molecules, intracellular post‐translational modifications of proline and lysine residues having key roles in this. In this article, we provide a review on the enzymes responsible for the proline and lysine modifications, that is collagen prolyl 4‐hydroxylases, 3‐hydroxylases and lysyl hydroxylases, and discuss their biological functions and involvement in diseases.  相似文献   
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10.
Vγ9Vδ2 T cells are attractive effector cells for immunotherapy with potent cytotoxic activity against a variety of malignant cells. However, the effect of Vγ9Vδ2 T cells on chemotherapy-resistant acute myeloid leukemia (AML) blasts, especially highly refractory leukemia stem cells (LSCs) is still unknown. In this study, we investigated the effect of cytotoxicity of allogeneic Vγ9Vδ2 T cells on chemotherapy-resistant AML cell lines, as well as on primary AML blasts and LSCs obtained from refractory AML patients. The results indicated that Vγ9Vδ2 T cells can efficiently kill drug-resistant AML cell lines in vitro and in vivo, and the sensitivity of AML cells to Vγ9Vδ2 T cell–mediated cytotoxicity is not influenced by the sensitivity of AML cells to chemotherapy. We further found that Vγ9Vδ2 T cells exhibited a comparable effect of cytotoxicity against LSCs to primary AML blasts. More importantly, we revealed that the CD226–extracellular signal–regulatory kinase1/2 (ERK1/2)–lysosome-associated membrane protein 1 (LAMP1) pathway is an important mechanism for Vγ9Vδ2 T cell–induced cytotoxicity against AML cells. First, Vγ9Vδ2 T cells recognized AML cells by receptor-ligand interaction of CD226–Nectin-2, which then induced ERK1/2 phosphorylation in Vγ9Vδ2 T cells. Finally, triggering the movement of lytic granules toward AML cells induced cytolysis of AML cells. The expression level of Nectin-2 may be used as a novel marker to predict the susceptibility/resistance of AML cells to Vγ9Vδ2 T cell treatment.  相似文献   
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