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41.
E3 ubiquitin ligases primarily determine the substrate specificity of the ubiquitin-proteasome system and play an essential role in the resistance to bortezomib in multiple myeloma (MM). Neural precursor cell-expressed developmentally downregulated gene 4-1 (NEDD4-1, also known as NEDD4) is a founding member of the NEDD4 family of E3 ligases and is involved in the proliferation, migration, invasion and drug sensitivity of cancer cells. In the present study, we investigated the role of NEDD4-1 in MM cells and explored its underlying mechanism. Clinically, low NEDD4-1 expression has been linked to poor prognosis in patients with MM. Functionally, NEDD4-1 knockdown (KD) resulted in bortezomib resistance in MM cells in vitro and in vivo. The overexpression (OE) of NEDD4-1, but not an enzyme-dead NEDD4-1-C867S mutant, had the opposite effect. Furthermore, the overexpression of NEDD4-1 in NEDD4-1 KD cells resensitized the cells to bortezomib in an add-back rescue experiment. Mechanistically, pAkt-Ser473 levels and Akt signaling were elevated and decreased by NEDD4-1 KD and OE, respectively. NEDD4-1 ubiquitinated Akt and targeted pAkt-Ser473 for proteasomal degradation. More importantly, the NEDD4-1 KD-induced upregulation of Akt expression sensitized MM cells to growth inhibition after treatment with an Akt inhibitor. Collectively, our results suggest that high NEDD4-1 levels may be a potential new therapeutic target in MM.  相似文献   
42.
目的 探讨CT引导徒手腔内联合插植实现影像引导自适应后装(IGABT)相较于传统A点二维后装(CP)剂量学优势,明确其在宫颈癌治疗中的价值。方法 选取在中山大学肿瘤医院行全量放疗的宫颈癌患者 26例,每例患者行4次后装治疗。治疗时先徒手置入宫腔管及2根插植针,后增加插植针数量并调整方向、深度,分别行CT扫描获得2套图像。勾画高危临床靶区(HRCTV),A点和危及器官(直肠、膀胱及乙状结肠)。在2套图像上分别行CP和IGABT计划设计,并配对t检验、Wilcoxon检验两者剂量参数差异。结果 以CP计划的覆盖指数(CI)进行分组,A组(CI≥0.90)包含20个CP和对应IGABT计划,B组(CI<0.90)包含84个CP和对应IGABT计划。A组的HRCTV体积及肿瘤直径明显小于B组(46.7cm3∶62.1cm3,P<0.001及3.1cm∶4.4cm,P<0.0001)。IGABT显著提高所有及B组D90%及覆盖指数,降低膀胱剂量,减少A组乙状结肠剂量,并改善剂量适形度及均匀性。结论 IGABT能提高靶区覆盖、剂量适形度和均匀性,保护危及器官,且对肿瘤较大的患者仍有优势。  相似文献   
43.
This study aimed to investigate the efficacy, safety, and prognostic factors of drug-eluting beads transarterial chemoembolization (DEB-TACE) in treating Chinese patients with liver cancer. A total of 367 liver cancer patients from 24 medical centers were consecutively enrolled in this multiple-center, prospective cohort study, including 275 hepatocellular carcinoma (HCC) cases, 37 intrahepatic cholangiocarcinoma (ICC) cases, and 55 secondary liver cancer cases. All the patients received CalliSpheres® DEB-TACE treatment. Treatment response, overall survival (OS), change of liver function, and adverse events (AEs) were assessed. DEB-TACE treatment achieved 19.9% complete response (CR) and 79.6% objective response rate (ORR), with mean OS of 384 days [95% confidence interval (CI): 375–393 days]. CR and ORR were both higher in HCC patients compared with primary ICC patients and secondary liver cancer patients, while no difference was discovered in OS. Portal vein invasion was an independent risk factor for CR, while portal vein invasion, previous conventional TACE (cTACE) treatment, and abnormal blood creatinine (BCr) were independent risk factors for ORR. In addition, largest nodule size 5.0 cm, abnormal albumin (ALB), and abnormal total bilirubin (TBIL) independently correlated with unfavorable OS. Most liver function indexes were recovered to baseline levels at 1–3 months after DEB-TACE. Common AEs were pain, fever, vomiting, and nausea; most of them were at mild grade. CalliSpheres® DEB-TACE is efficient and well tolerated in Chinese liver cancer patients. Portal vein invasion, previous cTACE treatment, largest nodule size, abnormal BCr, ALB, and TBIL correlate with worse prognosis independently.  相似文献   
44.
Salvia miltiorrhiza is one of the most commonly used traditional Chinese medicines in the treatment of cardiovascular and cerebrovascular diseases. Cryptotanshinone (CTS), tanshinone IIA (Tan IIA), dihydrotanshinone I (diTan I), and tanshinone I (Tan I) are the main active compounds in the liposoluble extract of Salvia miltiorrhiza. The differences in the pharmacokinetic and tissue distribution behaviors of the four tanshinones after oral administration of the liposoluble extract of Salvia miltiorrhiza and pure compounds are not clear. This study aims to compare the pharmacokinetics and tissue distribution of the four tanshinones after oral administration of pure tanshinone monomers and the liposoluble extract of Salvia miltiorrhiza. An ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) analysis method was developed for the determination of the four tanshinones. The results showed that the AUC and Cmax of tanshinones in rats receiving the extract of Salvia miltiorrhiza were significantly increased compared with those receiving the pure tanshinones. In the tissue distribution experiments, the AUC of the four tanshinones in the extract was much greater than the AUC of the monomers in the lung, heart, kidney, liver, and brain, and the coexisting constituents particularly promoted the distribution of tanshinones into tissues that the drug cannot sufficiently penetrate. These findings suggested that the coexisting constituents in the liposoluble extract of Salvia miltiorrhiza play an important role in the alteration of plasma concentration and tissue distribution of the four tanshinones. Understanding these differences could be of significance for the development and application of Salvia miltiorrhiza extract and tanshinone components.  相似文献   
45.
46.
目的探讨纤维蛋白原/白蛋白比值比(FAR)对可手术乳腺癌患者预后的影响。 方法依据纳入、排除标准,收集中国医学科学院北京协和医院2013年1~12月收治的520例Ⅰ~Ⅲ期可手术乳腺癌患者临床资料进行回顾性研究。在术前检测血浆纤维蛋白原和白蛋白水平。将纤维蛋白原与白蛋白质量浓度比值乘以100定义为FAR。根据受试者工作特征曲线确定FAR最佳临界值,并依据最佳临界值将受试者分为高FAR组(FAR>6.99)147例和低FAR组(FAR≤6.99)343例。采用Kaplan-Meier法和log-rank检验评估2组患者的DFS和OS,用Cox比例风险回归模型分析患者DFS和OS的影响因素。 结果log-rank检验显示,高FAR组患者的DFS和OS均比低FAR组差(χ2=32.885、16.320,P均<0.001)。Cox比例风险回归模型单因素分析和多因素分析均显示:高FAR为患者DFS的独立危险因素(HR=4.092,95%CI:2.425~6.903,P<0.001;HR=4.226,95%CI:2.476~7.212,P<0.001);高FAR为患者OS的独立危险因素(HR=3.907,95%CI:1.913~7.978,P<0.001;HR=4.320,95%CI:2.087~8.942,P<0.001)。 结论术前高FAR患者的无疾病进展时间更短,OS率更低。术前FAR水平有望成为预测乳腺癌患者预后的有效指标。  相似文献   
47.
Abstract

The autoimmune condition Hashimoto’s thyroiditis (HT) is a disease wherein lymphocytes mediate the autoimmune damage and destruction of the thyroid gland. There are currently no effective means of treating HT, with the primary strategies of thyroid hormone therapy, surgery, or immunomodulatory therapy being associated with serious risks and side effects. There is thus a clear and urgent need to identify novel treatments for HT. In this study, we utilize female SD rats induced HT to evaluated the ability of transplanted MSCs to regulate Th17/Treg interactions in a rat Hashimoto’s thyroiditis (HT) model system. The results showed that Rats in the HT model group exhibited increased thyroid autoantibody levels consistent with successful model development, whereas these levels were lower in rats treated with MSCs. There were also fewer thyroid lesions and less lymphoid infiltration of the thyroid in MSC-treated rats relative to HT model rats, as well as fewer Th17 cells and more Treg cells – an observation consistent with the cytokine analyses. All of these showed that MSCs can regulate Th17/Treg interactions in a rat Hashimoto’s thyroiditis (HT) model system. It suggested that transplanted MSCs could be a potential immunotherapy strategy for the treatment of Hashimoto’s thyroiditis.  相似文献   
48.
Angiogenesis plays an important role in the occurrence and development of tumors. Registered tyrosine kinase inhibitors targeting vascular endothelial growth factor reduce angiogenesis. Apatinib, a tyrosine kinase inhibitor, can specifically inhibit vascular endothelial growth factor receptor 2, showing encouraging anti-tumor effects in a variety of tumors including advanced hepatocellular carcinoma(HCC). This article intends to review the clinical research and application prospects of apatinib in the field of HCC.  相似文献   
49.
目的 丁书文教授创新性地提出了心系疾病热毒学说,运用益气活血解毒法治疗房颤疗效显著。本研究以丁教授多年的处方数据为基础,探讨丁教授益气活血解毒法治疗房颤的用药规律。方法 收集来自山东中医药大学附属医院门诊系统的丁书文教授处方数据,筛选出治疗房颤的372个处方,采用关联规则、点式互信息、复杂网络等数据挖掘方法对丁教授的药物配伍和处方进行分析。结果 本研究利用复杂网络分析方法获得了丁教授治疗房颤的核心处方,提示益气活血解毒法是其主要治则治法;利用处方相似性和社团分析方法,获得15组类方,其中3种类方与丁教授总结的三大治法高度符合;为探寻丁教授清热解毒配伍特点,结合关联规则和点式互信息算法,获得了10个丁教授清热解毒配伍药对。结论 数据挖掘技术提供了名医处方数据分析与提炼的可行方法,对丁教授经验的传承和临床应用提供直接可靠的依据。  相似文献   
50.
Solute carrier family 12 member 5 (SLC12A5) has an oncogenic role in bladder urothelial carcinoma. The present study aimed to characterize the molecular mechanisms of SLC12A5 in bladder urothelial carcinoma pathogenesis. Functional assays identified that in bladder urothelial carcinoma SLC12A5 interacts with and stabilizes SOX18, and then upregulates matrix metalloproteinase 7 (MMP7). In vivo and in vitro assays were performed to confirm the effect of SLC12A5’s interaction with SOX18 on MMP7‐mediated bladder urothelial carcinoma progression. SLC12A5 was upregulated in human bladder tumors, and correlated with the poor survival of patients with bladder urothelial carcinoma tumor invasion and metastasis, promoted by SLC12A5 overexpression. We demonstrated that SLC12A5 interacted with SOX18, and then upregulated MMP7, thus enhancing tumor progression. Importantly, SLC12A5 expression correlated positively with SOX18 and MMP7 expression in bladder urothelial carcinoma. Furthermore, SLC12A5 expression was suppressed by miR‐133a‐3p. Ectopic expression of SLC12A5 partly abolished miR‐133a‐3p‐mediated suppression of cell migration. SLC12A5‐SOX18 complex‐mediated upregulation on MMP7 was important in bladder urothelial carcinoma progression. The miR‐133a‐3p/SLC12A5/SOX18/MMP7 signaling axis was critical for progression, and provided an effective therapeutic approach against bladder urothelial carcinoma.  相似文献   
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