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91.
Sorafenib provides survival benefits in patients with advanced renal cell carcinoma (RCC), but its use is hampered by acquired drug resistance. It is important to fully clarify the molecular mechanisms of sorafenib resistance, which can help to avoid, delay or reverse drug resistance. Extracellular vesicles (EVs) can mediate intercellular communication by delivering effector molecules between cells. Here, we studied whether EVs are involved in sorafenib resistance of RCC and its possible molecular mechanisms. Using differential centrifugation, EVs were isolated from established sorafenib-resistant RCC cells (786-0 and ACHN), and EVs derived from sorafenib-resistant cells were uptaken by sensitive parental RCC cells and thus promoted drug resistance. Elevated exogenous miR-31-5p within EVs effectively downregulated MutL homolog 1 (MLH1) expression and thus promoted sorafenib resistance in vitro. Mice experiments also confirmed that miR-31-5p could mediate drug sensitivity in vivo. In addition, low expression of MLH1 was observed in sorafenib-resistant RCC cells and upregulation of MLH1 expression restored the sensitivity of resistant cell lines to sorafenib. Finally, miR-31-5p level in circulating EVs of RCC patients with progressive disease (PD) during sorafenib therapy was higher when compared to that in the pretherapy status. In conclusion, EVs shuttled miR-31-5p can transfer resistance information from sorafenib-resistant cells to sensitive cells by directly targeting MLH1, and thus magnify the drug resistance information to the whole tumor. Furthermore, miR-31-5p and MLH1 could be promising predictive biomarkers and therapeutic targets to prevent sorafenib resistance.  相似文献   
92.
《中国现代医生》2020,58(22):74-77
目的 探讨儿童慢性腹泻高营养风险情况及对预后的影响。方法 选择2019年1~12月在我院诊断治疗的慢性腹泻患儿100例为研究对象,进行营养风险筛查,分析高营养风险患儿与非高营养风险患儿临床特征以及预后情况,分析性别、年龄、病因对慢性腹泻患儿高营养风险的影响。结果 (1)100例患儿24例患儿STAMP评分≥4分,为高营养风险组,占24.0%。(2)7~14岁患儿高营养风险发生率显著高于其他年龄段患儿(P0.05);炎症性肠病患儿高营养风险发生率显著其他病因的患儿(P0.05)。(3)炎症性肠病是慢性腹泻患儿发生高营养风险的独立危险因素(P0.05)。(4)高营养风险组白蛋白、前白蛋白水平显著低于非高营养风险组,差异有统计学意义(P0.05)。两组Hb水平比较差异无统计学意义(P0.05)。(5)非高营养风险组痊愈率显著高于高营养风险组,医院感染率显著低于高营养风险组,住院时间显著短于高营养风险组,差异均有统计学意义(P0.05)。结论 儿童慢性腹泻高营养风险发生率相对较高,病因会影响患儿高营养风险的发生,而高营养风险影响患儿的预后,延长住院时间。  相似文献   
93.
Objective To analyze the early mortality and related risk factors of new hemodialysis patients in Zhejiang province, and provide basis for reducing the death risk of hemodialysis patients. Methods The early mortality and related factors of new hemodialysis patients from January 1, 2010 to June 30, 2018 were retrospectively analyzed using the database of Zhejiang province hemodialysis registration. The early mortality was defined as death within 90 days of dialysis. Cox regression model was used to analyze the related risk factors of the early mortality in hemodialysis patients. Results The mortality was the highest in the first month after dialysis (46.40/100 person year), and gradually stabilized after three months. The early mortality was 25.33/100 person year. The mortality within 120 days and 360 days were 21.40/100 person year and 11.37/100 person year, respectively. The elderly (≥65 years old, HR=1.981, 95%CI 1.319-2.977, P<0.001), primary tumor (HR=3.308, 95%CI 1.137-5.624, P=0.028), combined with tumors (not including the primary tumor, HR=2.327, 95%CI 1.200-4.513, P=0.012), temporary catheter (the initial dialysis pathway, HR=3.632, 95%CI 1.806-7.307, P<0.001), lower albumin (<30 g/L, HR=2.181, 95%CI 1.459-3.260, P<0.001), lower hemoglobin (every 0.01 g/L increase, HR=0.861, 95%CI 0.793-0.935, P=0.001), lower high density lipoprotein (<0.7 mmol/L, HR=1.796, 95%CI 1.068-3.019, P=0.027) and higher C reactive protein (≥40 mg/L, HR=1.889, 95%CI 1.185-3.012, P=0.008) were the risk factors of early death for hemodialysis patients. Conclusions The early mortality of hemodialysis patients is high after dialysis, and gradually stable after 3 months. The elderly, primary tumor, combined with tumors, the initial dialysis pathway, lower albumin, lower hemoglobin, lower high density lipoprotein and higher C reactive protein are the risk factors of early death for hemodialysis patients.  相似文献   
94.
Multidrug resistance due to facilitated drug efflux mediated by ATP-binding cassette (ABC) transporters is a main cause for failure of cancer therapy. Genetic polymorphisms in ABC genes affect the disposition of chemotherapeutics and constitute important biomarkers for therapeutic response and toxicity. Here we correlated germline variability in ABC transporters with disease-specific survival (DSS) in 960 breast cancer (BRCA), 314 clear cell renal cell carcinoma and 325 hepatocellular carcinoma patients. We find that variant burden in ABCC1 is a strong predictor of DSS in BRCA patients, whereas candidate polymorphisms are not associated with DSS. This association is highly drug-specific for subgroups treated with the MRP1 substrates cyclophosphamide (log-rank p = 0.0011) and doxorubicin (log-rank p = 0.0088) independent of age and tumor stage, whereas no association was found in individuals treated with tamoxifen (log-rank p = 0.13). Structural mapping of significant variants revealed multiple variants at residues involved in protein stability, cofactor stabilization or substrate binding. Our results demonstrate that BRCA patients with high variant burden in ABCC1 are less prone to respond appropriately to pharmacological therapy with MRP1 substrates, thus incentivizing the consideration of genomic germline data for precision cancer medicine.  相似文献   
95.
[目的] 运用网络药理学方法分析优化新生脉散方治疗慢性心力衰竭(CHF)的作用机制。[方法] 基于中药系统药理数据库和分析平台(TCMSP)、BATMAN-TCM及UniProt数据库查询优化新生脉散方药物的主要活性成分与相应靶点,利用GeneCards数据库检索CHF相关靶点,通过OmicShare网站分析并结合Cytoscape-v3.6.0软件构建优化新生脉散方中药-化合物-靶点-疾病网络图,使用DAVID数据库对潜在靶点进行基因功能(GO)及京都基因和基因组百科全书(KEGG)通路富集分析。[结果] 根据类药性(DL)、口服吸收利用度(OB)、参数评分(Scorecutoff)筛选出与CHF相关的潜在化合物85种及靶点89个,其中,化合物有quercetin、luteolin、kaempferol等,靶点包括SCN5A、ADRB2、NOS2等。功能富集分析涉及生物过程、分子功能、细胞组分的GO条目共497个,主要参与调控细胞凋亡、增殖及缺氧、炎症反应等方面,KEGG通路富集得到139条,主要与缺氧诱导因子-1(HIF-1)、磷脂酰肌醇3激酶/蛋白激酶B(PI3K-Akt)、肿瘤坏死因子(TNF)信号通路等有关。[结论] 优化新生脉散方治疗CHF具有多成分、多靶点、多途径的作用,为进一步研究优化新生脉散方治疗CHF的潜在复杂机制提供参考方向。  相似文献   
96.
目的探讨肺源性心脏病(肺心病)并呼吸衰竭患者运用低分子肝素钙进行治疗的临床应用价值。方法72例肺心病并呼吸衰竭患者,应用随机数字表法分为观察组和对照组,每组36例。对照组患者采取常规治疗,观察组患者在对照组上采用低分子肝素钙治疗。对比两组患者治疗前后动脉血气指标[氧分压(PaO2)、二氧化碳分压(PaCO2)及酸碱度(pH)值]及治疗效果。结果治疗前,两组患者的PaO2、PaCO2、pH值水平比较,差异无统计学意义(P>0.05);治疗后,观察组患者的PaO2(9.36±1.02)kPa明显高于对照组的(7.78±0.98)kPa,PaCO2(6.33±0.97)kPa明显低于对照组的(7.65±1.28)kPa,差异均具有统计学意义(P<0.05);两组患者pH值比较差异无统计学意义(P>0.05)。观察组患者总有效率为97.22%,显著高于对照组的83.33%,差异具有统计学意义(P<0.05)。结论针对肺心病并呼吸衰竭患者运用低分子肝素钙进行治疗,可有效改善患者的血气指标,提高治疗效果,具有较高的临床价值。  相似文献   
97.
目的:探讨miR-361-5p对肾细胞癌ACHN细胞增殖、侵袭、迁移、凋亡及其细胞周期的影响。方法:将miR-361-5p mimics和miR-361-5p inhibitor分别转染至肾癌ACHN细胞中,用qPCR检测转染细胞中miR-361-5p的表达水平,用MTT法、划痕愈合实验、Transwell实验、流式细胞术分别检测细胞的增殖、迁移、侵袭、细胞周期和凋亡水平。结果:与空白对照组和 Mimics-NC组比较,miR-361-5p mimics组ACHN细胞中miR-361-5p表达水平显著升高(P<0.01),细胞的增殖、侵袭和迁移能力均显著减弱(均P<0.01),而凋亡率升高(P<0.01)。与空白对照组或Inhibitor-NC组比较,miR-361-5p inhibitor组细胞中miR-361-5p表达水平显著下降(P<0.01),细胞的增殖、侵袭和迁移能力均增强(均P<0.01),细胞周期运转加速(P<0.01),凋亡率降低(P<0.05)。结论:miR-361-5p可抑制肾癌ACHN细胞的增殖、侵袭和迁移,并诱导细胞凋亡,其在肾癌发生发展过程中发挥重要的抑制作用。  相似文献   
98.
目的:探索健脾生血片治疗慢性心力衰竭伴贫血的疗效、安全性和作用机制。方法:选取2016年5月至2017年2月同济医院收治的慢性心力衰竭贫血患者144例,按照随机数字表法分为观察组和对照组,每组72例。观察组给予健脾生血片治疗,3片/次,3次/d,疗程3个月;对照组给予生血宝合剂治疗,15 m L/次,3次/d,3个月为1个疗程。比较2组患者治疗前与治疗后血红蛋白、红细胞计数、网织红细胞、血清铁、转铁蛋白饱和度、血清铁蛋白、血清铁调素(Hepcidin)、血清IL-1β、血清肿瘤坏死因子-α(TNF-α)、血清C反应蛋白(CRP)、左室射血分数(LVEF)、6 min步行距离、明尼苏达心力衰竭生命质量量表(MLHFQ)和不良事件。并随访2组心血管事件次数,住院次数与全因死亡率。结果:观察组72例患者完成了前3个月的治疗,随访期间脱失2例;对照组治疗期间1例患者退出研究,随访期间脱失4例。2组一般资料比较,差异无统计学意义(P 0. 05),具有可比性。观察组贫血有效率98. 6%,对照组有效率11. 3%,差异有统计学意义(P0. 05)。治疗后观察组红细胞计数和网织红细胞、均显著高于对照组(P 0. 05)。观察组血清铁、转铁蛋白饱和度水平均高于对照组,差异有统计学意义(P 0. 05),但血清铁调素水平显著低于对照组,差异有统计学意义(P 0. 05),血清铁蛋白水平2组差异无统计学意义(P 0. 05)。观察组IL-1β、血清TNF-α、血清CRP均显著低于对照组,差异有统计学意义(P 0. 05)。观察组LVEF、6 min步行距离、明尼苏达心力衰竭生命质量量表(MLHFQ)均显著高于对照组,差异有统计学意义(P 0. 05)。2组不良事件总发生率比较,差异无统计学意义(P 0. 05),但对照组4例患者出现血清肌酐、尿素氮水平异常,发生率高于观察组,差异有统计学意义(P 0. 05)。经1年随访,观察组心血管事件人均发生次数显著少于对照组(P 0. 05),但2组住院次数和全因死亡率比较,差异无统计学意义(P 0. 05)。结论:健脾生血片可有效治疗心力衰竭伴贫血,减少心血管发生次数,并且安全性良好,其作用机制与提供准确足量铁元素、抑制铁调素表达,抑制慢性炎性反应有关。  相似文献   
99.
周晓虹教授认为脾胃亏虚是慢性萎缩性胃炎发病的病机关键,而寒凝、气郁、血瘀及湿阻等则是重要的发病因素,采用健脾益气的方法治疗主证,兼用温阳、理气、活血、化湿等方法治疗兼证,同时结合辨病,宏观与微观互参,可以收到满意的疗效。  相似文献   
100.
IntroductionThe presence of FMS-like tyrosine kinase 3 (FLT3) internal tandem duplication (ITD) mutation in pediatric acute myeloid leukemia (AML) is associated with high rates of induction failure and worse survival. Its presence places the patient into a high-risk group. We aimed to describe the outcome of pediatric AML with FLT3-ITD mutation.Patients and MethodsWe performed a retrospective analysis of cases of AML from July 2007 till July 2017 at Children’s Cancer Hospital Egypt.ResultsSeventy-one patients had FLT3 gene mutation out of 687 patients with AML. Sixty-five patients had FLT3 gene mutation with allelic ratio > 0.4; 43 (66.1%) of 65 patients experienced complete remission (CR). Of the 43 patients, 16 patients maintained CR, 18 patients relapsed after first CR, 8 patients died, and 1 patient was lost to follow-up. Patients with relapsing disease died after salvage chemotherapy, except for one patient, who was alive after second CR. Allogeneic bone marrow transplantation (allo-BMT) was performed for 9 (13.8%) of 65 patients in first CR, of whom 8 were alive and in CR, and 1 patient experienced disease relapse and died. Seven patients (10.7%) were alive without allo-BMT. Three years’ overall and event-free survival for patients with FLT3-ITD mutation with high allelic ratio was 26.9% and 22.8%, respectively. Three years’ overall and event-free survival for patients treated with allo-BMT was 77.8% and 78.8%, respectively, versus patients treated without allo-BMT, 16.3% and 12.8%, respectively.ConclusionFLT3-ITD mutation in pediatric AML was associated with poor treatment outcomes, and the survival of relapsing patients was extremely poor. Allo-BMT in first remission was the best treatment option. Alternative donor transplants and FLT3 inhibitors are needed to improve outcome in developing countries.  相似文献   
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