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51.
During embryonic development, the lymphatic system emerges by transdifferentiation from the cardinal vein. Although lymphatic and blood vasculature share a close molecular and developmental relationship, they display distinct features and functions. However, even after terminal differentiation, transitions between blood endothelial cells (BEC) and lymphatic endothelial cells (LEC) have been reported. Since phenotypic plasticity and cellular differentiation processes frequently involve epigenetic mechanisms, we hypothesized that DNA methylation might play a role in regulating cell type-specific expression in endothelial cells. By analyzing global gene expression and methylation patterns of primary human dermal LEC and BEC, we identified a highly significant set of genes, which were differentially methylated and expressed. Pathway analyses of the differentially methylated and upregulated genes in LEC revealed involvement in developmental and transdifferentiation processes. We further identified a set of novel genes, which might be implicated in regulating BEC-LEC plasticity and could serve as therapeutic targets and/or biomarkers in vascular diseases associated with alterations in the endothelial phenotype.  相似文献   
52.
黄芩素干预快速老化小鼠SAMP8肝脏组织的代谢组学研究   总被引:1,自引:0,他引:1  
周峰  李佳琪  王珂欣  周玉枝  秦雪梅  高丽 《中草药》2019,50(11):2604-2611
目的基于~1H-NMR代谢组学技术,研究黄芩素对快速老化小鼠SAMP8肝脏的保护作用并探索其作用机制。方法采用SAMP8小鼠作为快速老化模型,考察黄芩素(ig)对SAMP8小鼠肝脏的保护作用。小鼠随机分3组,对照组为SAMR1小鼠、模型组为SAMP8小鼠、给药组为SAMP8小鼠+黄芩素。对照组和模型组给予等量生理盐水,给药组给予200 mg/kg黄芩素。分别取各组小鼠肝脏组织,采用苏木精-伊红(HE)染色观察其肝组织损伤程度,并对肝脏组织进行~1H-NMR检测,结合多元统计分析探讨黄芩素抗衰老小鼠肝损伤的作用。结果肝脏指数以及HE染色结果显示,黄芩素能明显改善SAMP8小鼠的肝损伤情况。代谢组学分析共找到8个潜在生物标志物,主要涉及3条代谢通路,分别是丙氨酸、天冬氨酸、谷氨酸代谢,甘氨酸、丝氨酸、苏氨酸代谢和肌醇磷酸代谢。结论黄芩素对SAMP8小鼠的肝损伤具有保护作用,其机制涉及多靶点、多途径。  相似文献   
53.
Electrocardiographic (ECG) artifacts resulting from misplacements of electrodes are frequent, difficult to detect, and can become of clinical importance. We investigated 2 healthy volunteers and 3 patients with ECG signs of inferior myocardial scars. We exchanged the peripheral electrodes in a defined manner and investigated the resulting ECG for morphology and possible diagnostic errors. In the volunteers, ECG signs of inferior ischemia could be produced. In the patients with ischemic heart disease, normal ECG without signs of ischemia resulted by placing the electrode of the left leg to the left arm. The automatic ECG analyzer was not helpful in detecting artifacts by misplaced electrodes. A very low amplitude of the QRS complex in lead I, II, or III was pathognomonic for electrode misplacement in half of the cases. ECG artifacts must also be suspected when abnormal QRS- or P-axis occur or when QRS morphology does not match with the clinical presentation of the patient.  相似文献   
54.
??Objective??To investigate the clinical features??diagnosis??treatment and prognosis of eosinophilic cystitis in pediatric population. Methods??The records of four patients who had been diagnosed and treated for eosinophilic cystitis from January 2012 to May 2015 in Shengjing Hospital were retrospectively reviewed. Results??All the four patients were boys whose age ranged from 6 to 8 years. The main symptoms of the 4 cases were frequent micturition??odynuria??dysuria??suprapubic pain and hematuria.All of the 4 cases had significant peripheral eosinophilia and increased bladder wall thickness. All of the patients were diagnosed with biopsy. Bladder interstitial eosinophil infiltration was revealed by histopathology. The clinical symptoms??peripheral eosinophilia and bladder imaging changes were relieved after steroids and antihistamines treatment. Three cases developed recurrence. Total course of oral corticosteroids ranged from 3 months to 18 months. One case remained persistent remission for 2 years??two cases had are recurrence and one case had two recurrences. Conclusion??Bladder biopsy is essential to establishing the diagnosis of eosinophilic cystitis. Patients with peripheral eosinophilia and the increased bladder wall thickness should be considered with eosinophilic cystitis. Steroids is effective as medical therapy for eosinophilic cystitis and close long-term follow-up is necessary.  相似文献   
55.
??Objective To investigate the clinical characteristics and treatment of hypereosinophilic syndrome??HES?? in children. Methods The clinical manifestations?? laboratory examinations??gastroscopy and imaging features??pathological results and therapy experience in 13 HES children admitted in Beijing Children’s Hospital??Capital Medical University from January 2009 to February 2016 and related literatures were analyzed retrospectively. Results Of the 13 patients evaluated?? 7 were male??54%?? and 6 were female??46%??. The median age at diagnosis was 9.6 years old??ranging 3 to 14 years old??. The median course of disease was 23 months??ranging 1 to 72 months??. The peripheral eosionophil counts ranged ??4.5—29.2??×109/L??mean 13.5×109/L??. Gastrointestinal tract was the most commonly involved organ?? and was reported in 92%??12/13?? of patients. It was followed in frequency by urinary system??84%????pulmonary??53%????cardiac??23%????and skin??8%?? and liver??8%??. A total of 2 sites were involved in 6 patients??3 sites were involved in 5 patients and 4 sites were involved in 2 patients. Treatment of oral prednisone therapy was given and follow-up of 10 patients had no clinical symptoms??2 patients had stopped prednisone??. But eosionophil counts still increased to varying degrees. Three patients were lost to follow-up. Conclusion HES in children is more common in school age and adolescent children. Gastrointestinal tract??urinary system and pulmonary involvement are more common. Glucocorticoid treatment is effective??which requires to be maintained in small dose in the long term.  相似文献   
56.
目的 探讨动态人工智能(AI)超声辅助诊断系统(以下简称动态AI)对甲状腺结节良恶性鉴别诊断价值及对治疗策略的指导意义。方法 选取2021年11月1日至2021年12月31日于中国人民解放军总医院第一医学中心甲状腺(疝)外科接受手术治疗的193例(共346枚结节)甲状腺结节病人,应用动态AI对结节进行良恶性鉴别,对比不同性别、年龄的病人其不同大小、性质的结节的动态AI检查结果、术前细针穿刺细胞学检查结果及术后病理学检查结果,评价动态AI诊断效能。结果 动态AI诊断甲状腺结节的灵敏度为88.5%,特异度为 76.5%,准确率为 85.0%,与术后病理学检查结果有较高一致性(Kappa=0.643,P<0.01)。对比动态AI检查和术前穿刺活检的灵敏度(χ2=0.210,P=0.647)和准确率(χ2=1.699,P=0.192)差异无统计学意义,特异度差异有统计学意义(χ2=7.238,P=0.007)。动态AI检查在不同性别(χ2=0.002,P=0.968)及年龄(χ2=3.913,P=0.41)人群中准确率差异无统计学意义,稳定性较好。良性结节的准确率(76.5%)较恶性结节的准确率(88.5%)低(χ2=8.184,P=0.004)。动态AI检查准确率随着结节大小增加有上升趋势(χ2=7.357,P=0.007),直径>1 cm结节准确率可达94.4%。结论 动态AI检查对甲状腺结节的良恶性有较高的诊断价值,且无创可重复、高效便捷、安全可靠,可减少不必要的穿刺,节约医疗资源及社会成本,可有效辅助外科医师为病人制定科学合理的个体化诊治策略。  相似文献   
57.
目的比较腹腔镜辅助保留幽门胃切除术(LAPPG)与腹腔镜辅助远端胃大部切除术(LADG)(BillrothⅠ式吻合)对胃体中部早期胃癌病人术后继发性胆汁反流性胃炎(BRG)的影响。方法自2018年2月至2018年12月,对上海交通大学医学院附属仁济医院胃肠外科收治的69例早期胃体中部癌(cT1N0M0)病人进行1∶1前瞻性随机化入组,其中LAPPG组(行LAPPG)34例,LADG组(行LADG,BillrothⅠ式吻合)35例,进行6个月随访,比较两组术前、术中、术后及随访结果。结果两组病人在年龄、性别、BMI、术前合并症及术后病理诊断的基线水平差异无统计学意义(P>0.05)。两组淋巴结清扫数目、手术时间、术中出血量、术后首次排气时间、胃管拔除时间、Ⅱ级以上并发症差异无统计学意义(P>0.05)。术后6个月随访结果显示,BRG临床表现无特异性,在两组中差异无统计学意义(P>0.05);但内镜下诊断BRG比例LAPPG组显著低于LADG组,差异有统计学意义[3例(8.8%)vs.16例(45.7%),χ^2=11.763,P=0.001];LAPPG组中Kellosalofen分级Ⅱ度以上BRG的比例显著低于LADG组,差异有统计学意义[2例(5.7%)vs.9例(25.7%),χ^2=5.062,P=0.024];组织学活检发现LADG组胃小凹增生1例、腺体萎缩伴肠化3例,LAPPG组未观察到上述病理组织学异常,但两组差异无统计学意义(P>0.05)。结论LAPPG治疗早期胃体中部癌安全可行,该术式较LADG可改善术后BRG的发生率及严重程度。其对病人术后长期疗效及残胃癌发生率的影响仍有待大样本RCT研究的长期随访证实。  相似文献   
58.
目的 探讨孤立性髂动脉瘤介入治疗的临床经验。方法 回顾性分析2010年1月至2018年9月昆明医科大学附属延安医院血管介入科采用覆膜支架介入治疗孤立性髂动脉瘤39例,术后3个月、6个月及之后的每年对病人进行随访,探讨相关治疗方法。结果 39例病人分型有1A:Ⅰ型1例,1B:Ⅱ型8例,1D:Ⅳ型17例,2B:Ⅱ型2例,2D:Ⅳ型1例,2E:V型10例。平均瘤体最大直径为(42.4±11.2)mm(23.0~77.0 mm)。39例病人均顺利完成介入手术治疗,技术成功率100%,术中保留双侧髂内动脉1例,保留一侧髂内动脉29例,双侧髂内动脉均封闭9例,术中行一侧髂内动脉栓塞9例,行双侧髂内动脉均栓塞1例,手术时间为(49.0±17.0)min(35.0~87.0 min),术后随访(31.9±17.7)个月(5~69个月),术后除1例左髂动脉瘤破裂且合并肾衰竭的病人死亡,其余病人均好转出院,复查CTA示髂动脉瘤被完全封闭,支架形态位置良好,无内漏及其他并发症。结论 孤立性髂动脉瘤起病隐匿,早期多无症状,CT等检查能够早期诊断。介入治疗是安全有效的方法。应注意在术前根据髂动脉瘤的累及范围,近远端有无足够的锚定区进行分型,并对不同分型进行有差别的个体化治疗。  相似文献   
59.
目的 探讨应用皮下负压引流器预防下消化道开腹手术切口愈合不良的价值。方法 回顾性分析2018年10月至2020年1月首都医科大学附属北京友谊医院普外科收治的113例下消化道开放手术病人的临床资料。根据腹壁缝合时是否放置皮下引流器,分为皮下引流组(78例)和对照组(35例)。比较两组病人切口愈合情况,分析切口愈合不良与临床特征的关系以及开放手术切口愈合不良的影响因素。结果 113例病人中,切口愈合不良发生率为14.2%(16/113),其中皮下引流组切口愈合不良发生率为5.1%(4/78),对照组为34.3%(12/35),两组差异具有统计学意义(P<0.05)。多因素分析提示,影响切口愈合不良发生的独立危险因素为未放置皮下引流器(OR=14.510,95%CI 3.411~61.735,P=0.001)、糖尿病(OR=7.064,95%CI 1.286~38.789,P=0.024)及吻合口漏/残端漏(OR=15.004,95%CI 1.876~119.996,P=0.011)。结论 下消化道开放手术切口愈合不良发生率较高,应用皮下负压引流器能有效减少其发生,且操作方便、价格低廉。  相似文献   
60.
目的 探讨经口腔前庭入路腔镜全甲状腺切除术(TOETVA)的有效性及安全性。方法 回顾性分析2017年7月至2019年7月浙江大学医学院附属第二医院甲状腺外科收治的行全甲状腺切除术且病理学检查确诊为甲状腺乳头状癌(PTC)的110例病人的临床资料,术前影像学检查提示无淋巴结转移(cN0)。其中51例行TOETVA(经口组),59例行开放甲状腺手术(开放组),对比两组临床病理学指标、手术效果以及随访情况。结果 两组病人术中喉返神经信号减弱比例、中央区淋巴结清扫数目、单双侧甲状腺清扫比例、淋巴结转移阳性率、阳性淋巴结数目及术后并发症(声音嘶哑、饮水呛咳、暂时性甲状旁腺功能减退及感染)差异均无统计学意义(P>0.05)。术后随访6个月,经口组与开放组病人的Tg和PTH水平差异无统计学意义(P=0.560、0.206),且均未发现两组有甲状腺残留及甲状腺癌复发转移征象。结论 TOETVA在有效性及安全性方面不劣于开放手术,且体表无手术瘢痕,尤其适合有美容要求的临床低危PTC病人。  相似文献   
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