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71.
《药学学报(英文版)》2020,10(5):799-811
Overexpression of adenosine triphosphate (ATP)-binding cassette subfamily G member 2 (ABCG2) in cancer cells is known to cause multidrug resistance (MDR), which severely limits the clinical efficacy of chemotherapy. Currently, there is no FDA-approved MDR modulator for clinical use. In this study, rociletinib (CO-1686), a mutant-selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), was found to significantly improve the efficacy of ABCG2 substrate chemotherapeutic agents in the transporter-overexpressing cancer cells in vitro and in MDR tumor xenografts in nude mice, without incurring additional toxicity. Mechanistic studies revealed that in ABCG2-overexpressing cancer cells, rociletinib inhibited ABCG2-mediated drug efflux and increased intracellular accumulation of ABCG2 probe substrates. Moreover, rociletinib, inhibited the ATPase activity, and competed with [125I] iodoarylazidoprazosin (IAAP) photolabeling of ABCG2. However, ABCG2 expression at mRNA and protein levels was not altered in the ABCG2-overexpressing cells after treatment with rociletinib. In addition, rociletinib did not inhibit EGFR downstream signaling and phosphorylation of protein kinase B (AKT) and extracellular signal-regulated kinase (ERK). Our results collectively showed that rociletinib reversed ABCG2-mediated MDR by inhibiting ABCG2 efflux function, thus increasing the cellular accumulation of the transporter substrate anticancer drugs. The findings advocated the combination use of rociletinib and other chemotherapeutic drugs in cancer patients with ABCG2-overexpressing MDR tumors.  相似文献   
72.
[目的]研究真武汤合苓桂术甘汤对心肾综合征大鼠模型水钠潴留的作用机制。[方法]将60只雄性SD大鼠随机分为两组,即空白组与手术组,空白组大鼠常规饲养,手术组大鼠经5/6肾切除联合异丙肾上腺素皮下注射制备心肾综合征模型,剔除死亡大鼠后,将手术组剩余成模大鼠按体质量分层随机分为空白组、中药组、常规治疗组。中药组给予真武汤合苓桂术甘汤灌胃,给药量为7.29 g生药/(kg·d);常规治疗组给予贝那普利(0.45 mg/kg)+呋塞米(1.8m g/kg);空白组予以等容积生理盐水灌胃,每日1次,连续6周。观察实验过程中各组大鼠的精神状态、活动情况、灵敏度、毛发情况、食欲、大小便等一般情况及死亡情况,比较各组灌胃前、灌胃6周后的血清脑钠肽(BNP)、血肌酐(Scr)、血尿素氮(BUN)、尿水通道蛋白2(AQP2)的前后差值情况。[结果]灌胃6周后,中药组大鼠一般情况较灌胃前改善、喘息不明显,常规治疗组一般情况同样较灌胃前改善。通过比较治疗前后各组大鼠实验室指标差值发现,中药组与常规治疗组BNP均下降,中药改善大鼠心力衰竭情况接近常规治疗组水平,两组下降水平无统计学差异(P0.05);中药组Scr水平较前下降,常规治疗组Scr水平升高;中药组尿AQP2水平较前略增高,与空白组尿AQP2水平无统计学差异(P0.05),常规治疗组尿AQP2水平较前明显升高。[结论]心肾综合征大鼠尿AQP2的表达主要由肾脏调控,AQP2可作为心肾综合征水钠潴留状态的参考指标,真武汤合苓桂术甘汤改善心肾综合征大鼠水钠潴留状态的作用机制可能是通过抑制大鼠肾脏AQP2过度表达,减少水的重吸收,改善了水钠潴留状态。  相似文献   
73.
目的:观察综合疗法治疗慢性肾脏病(CKD)4~5期脾肾亏虚证的效果。方法:将CKD4~5期脾肾亏虚证患者62例随机分为2组,其中治疗组31例,对照组30例(剔除1例)。对照组予基础治疗合中药、骨化三醇及碳酸钙D3片治疗,治疗组予基础治疗合中药、骨化三醇及益肾泄浊汤保留灌肠治疗,观察时间为4周。比较2组血肌酐(Scr)、肾小球滤过率(e GFR)、尿素氮(BUN)、血钙、血磷、碱性磷酸酶(ALP)、甲状旁腺激素(i PTH)及中医证候疗效。结果:中医证候总有效率治疗组为83.87%(26/31),对照组为73.33%(22/30),组间比较,差异有统计学意义(P<0.05);2组Scr、e GFR、BUN、血磷治疗前后组内比较及治疗后组间比较,差异均有统计学意义(P<0.01或P<0.05);2组血钙、i PTH、ALP治疗前后组内比较,差异均有统计学意义(P<0.01),但治疗后组间比较,差异无统计学意义(P>0.05)。结论:综合疗法治疗慢性肾脏病4~5期脾肾亏虚证效果确切,安全可靠。  相似文献   
74.
宋洋  任芳 《现代肿瘤医学》2020,(14):2365-2369
目的:探讨miR-590-5p在卵巢癌组织中的表达情况以及其对卵巢癌细胞增殖的影响及作用机制。方法:Real-time PCR和双荧光素酶实验确定miR-590-5p与lncRNA SNHG1之间的调控作用。Real-time PCR检测卵巢癌、癌旁组织以及卵巢癌细胞中miR-590-5p的表达。分别采用NC mimic或者miR-590-5p mimic转染两株卵巢癌细胞,CCK-8检测各组细胞的增殖情况。此外,Real-time PCR检测两株细胞中SOX2、RECK和YAP1的表达。结果:Real-time PCR结果显示下调SNHG1后miR-590-5p的表达显著升高。双荧光素酶结果显示转染miR-590-5p mimic和野生型SNHG1片段的细胞中荧光素酶的活性显著降低。此外,Real-time PCR结果显示miR-590-5p在卵巢癌组织中的表达水平显著低于癌旁组织。CaOV3、OV-90细胞中miR-590-5p的表达水平明显低于其他卵巢癌细胞。转染miR-590-5p mimic显著上调了CaOV3、OV-90细胞中miR-590-5p的表达并且抑制了这两株细胞的增殖,同时抑制了两株细胞中SOX2、RECK和YAP1的表达。结论:miR-590-5p的低表达与卵巢癌的进展密切相关,miR-590-5p能够介导SNHG1信号并且通过对其下游靶基因的调控抑制卵巢癌细胞的增殖。  相似文献   
75.
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   
76.
Macrophages are the most abundant immune cells in the lung, which play an important role in COPD. The anti-inflammatory and anti-oxidation of ergosterol are well documented. However, the effect of ergosterol on macrophage polarization has not been studied. The objective of this work was to investigate the effect of ergosterol on macrophage polarization in CSE-induced RAW264.7 cells and Sprague-Dawley (SD) rats COPD model. Our results demonstrate that CSE-induced macrophages tend to the M1 polarization via increasing ROS, IL-6 and TNF-α, as well as increasing MMP-9 to destroy the lung construction in both RAW264.7 cells and SD rats. However, treatment of RAW264.7 cells and SD rats with ergosterol inhibited CSE-induced inflammatory by decreasing ROS, IL-6 and TNF-α, and increasing IL-10 and TGF-β, shuffling the dynamic polarization of macrophages from M1 to M2 both in vitro and in vivo. Ergosterol also decreased the expression of M1 marker CD40, while increased that of M2 marker CD163. Moreover, ergosterol improved the lung characters in rats by decreasing MMP-9. Furthermore, ergosterol elevated HDAC3 activation and suppressed P300/CBP and PCAF activation as well as acetyl NF-κB/p65 and IKKβ, demonstrating that HDAC3 deacetylation was involved in the effect of ergosterol on macrophage polarization. These results also provide a proof in immunoregulation of ergosterol for therapeutic effects of cultured C. sinensis on COPD patients.  相似文献   
77.
近年来,抗程序性细胞死亡蛋白1(PD-1)药物在转移性结直肠癌患者错配修复缺陷治疗中的成功使得该疾病的免疫治疗得以重视。然而,失配修复缺陷的结直肠癌患者仅占结肠癌患者的一部分。目前的研究重点是将免疫治疗应用到疾病的早期阶段,包括辅助一线治疗,以及检测免疫检查点抑制剂治疗的敏感性。然而,哪些患者能够从该免疫治疗中获益仍是值得商榷的问题,因为这类药物具有自身免疫毒性。PD-1的配体之一程序性细胞死亡蛋白配体1(PD-L1)作为一种检测生物标记物,其检测可以通过免疫组化来实现。但其免疫组化的检测存在一些混杂因素,包括应用不同的检测抗体、不同的免疫组化临界值、肿瘤组织的采集准备方式不同、处理过程的不同、原发与继发的活检标本、肿瘤源性或诱导的PD-L1表达,以及肿瘤与免疫细胞的染色等。目前的结果表明,免疫组化检测肿瘤过表达PD-L1的患者在接受抗PD-L1治疗时临床效果更理想,而有些低表达的肿瘤也对该治疗有所缓解,这使PD-L1的分析中存在复杂性。阐明宿主免疫系统与肿瘤微环境的机制则能够更好地解释针对PD-L1药物是否让患者受益。  相似文献   
78.
目的:为了验证丹参类黄酮-3′,5′-羟基化酶(Flavonoid 3′,5′-hydroxylase,F3′5′H)基因与丹参花色表型的相关性,本研究克隆并分析了紫花丹参99-3株系和一些白花丹参中的F3′5′H基因。方法:本研究通过提取紫花丹参和白花丹参中的总RNA,再将其反转录得到cDNA,以此cDNA为模板,利用PCR方法扩增获得F3′5′H基因全长序列。再利用生物信息学分析方法,分析了该基因编码蛋白质的理化性状、结构域、系统进化等特点,并预测了该蛋白质的亚细胞定位、跨膜区等;利用实时定量PCR方法检测了该基因的表达特异性;利用毛状根遗传转化方法获得了该基因的过表达阳性毛状根株系。结果:F3′5′H基因全长1551 bp,编码516个氨基酸,相对分子质量为57.4 kDa。该基因在丹参花中高丰度表达。在42份(紫花25份;白花17份)丹参样品中发现一个单核苷酸多态性(Single Nucleotide Polymorphisms,SNP)位点在紫花和白花丹参中呈现与花色相关的稳定变化。系统发育分析表明丹参F3′5′H与美女樱的F3′5′H具有较高序列同源性。获得了过表达F3′5′H的毛状根株系。结论:本研究在丹参中克隆到F3′5′H基因,对其序列进行了分析,为进一步研究丹参F3′5′H基因的功能奠定基础。  相似文献   
79.
目的:探讨银杏内酯B(ginkgolide B,GB)对肌萎缩侧索硬化细胞模型c-Jun氨基末端激酶(JNK)信号通路及细胞凋亡的影响。方法:通过含过表达人突变超氧化物歧化酶1(SOD1)~(G93A)基因(hSOD1~(G93A))和过表达人野生SODWT基因(hSOD1WT)与空质粒的慢病毒感染NSC34细胞,经一定浓度的嘌呤霉素筛选,倒置荧光显微镜下观察慢病毒的转染效率和细胞形态的变化,蛋白免疫印迹法(Western blot)检验感染细胞是否过表达SOD1蛋白,建立hSOD1~(G93A)-NSC34细胞系后给予GB,细胞培养分组为正常组、模型组、不同浓度GB组(25,50,75,100 mg·L-1)组,48 h后噻唑蓝(MTT)比色法检测细胞存活率,筛选出最佳药物浓度,后续实验分组为以正常组,模型组,75 mg?L~(-1) GB组,SP600125组,75 mg?L-1GB+SP600125组,流式细胞术检测各组细胞的凋亡率,蛋白免疫印迹法(Western blot)检测磷酸化(p-)JNK,c-Jun,p-c-Jun,半胱氨酸天冬氨酸蛋白酶-3(Caspase-3)蛋白的表达。结果:与正常的NSC34细胞比较,hSOD1~(G93A)NSC34组细胞胞体变圆,突触减少、变短,而hSOD1WT NSC34组细胞和空质粒组细胞形态学未发生明显变化,与正常组比较,hSOD1~(G93A)NSC34组,hSOD1WTNSC3组细胞内SOD1蛋白水平显著升高(P0. 01),肌萎缩侧索硬化(ALS)细胞模型成功建立。与正常组比较,模型组细胞存活率显著降低(P0. 01);与模型组比较,给予不同浓度GB后,细胞存活率均显著升高(P0. 01),药物质量浓度为75 mg?L-1时细胞存活率显著升高(P0. 01)。后续实验,与正常组比较,模型组凋亡率,p-JNK,p-c-Jun,cleaved Caspase-3蛋白表达量显著升高(P0. 01);与模型组比较,75 mg?L-1GB组,SP600125组,75 mg?L-1GB+SP600125组凋亡率,p-JNK,p-c-Jun,cleaved Caspase-3蛋白表达明显降低(P0. 05,P0. 01)。结论:GB对肌萎缩侧索硬化细胞模型具有抑制细胞凋亡的保护作用,这种保护作用可能是通过JNK信号通路实现的。  相似文献   
80.
Previous studies have reported converging lung cancer rates between sexes. We examine lung cancer incidence rates in young women vs. young men in 40 countries across five continents. Lung and bronchial cancer cases by 5-year age group (ages 30–64) and 5-year calendar period (1993–2012) were extracted from Cancer Incidence in Five Continents. Female-to-male incidence rate ratios (IRRs) and 95% confidence intervals (95%CIs) were calculated by age group and birth cohort. Among men, age-specific lung cancer incidence rates generally decreased in all countries, while in women the rates varied across countries with the trends in most countries stable or declining, albeit at a slower pace compared to those in men. As a result, the female-to-male IRRs increased among recent birth cohorts, with IRRs significantly greater than unity in Canada, Denmark, Germany, New Zealand, the Netherlands and the United States. For example, the IRRs in ages 45–49 year in the Netherlands increased from 0.7 (95% CI: 0.6–0.8) to 1.5 (95% CI: 1.4–1.7) in those born circa 1948 and 1963, respectively. Similar patterns, though nonsignificant, were found in 23 additional countries. These crossovers were largely driven by increasing adenocarcinoma incidence rates in women. For those countries with historical smoking data, smoking prevalence in women approached, but rarely exceeded, those of men. In conclusion, the emerging higher lung cancer incidence rates in young women compared to young men is widespread and not fully explained by sex differences in smoking patterns. Future studies are needed to identify reasons for the elevated incidence of lung cancer among young women.  相似文献   
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