全文获取类型
收费全文 | 26984篇 |
免费 | 2602篇 |
国内免费 | 1432篇 |
专业分类
耳鼻咽喉 | 223篇 |
儿科学 | 373篇 |
妇产科学 | 193篇 |
基础医学 | 2806篇 |
口腔科学 | 620篇 |
临床医学 | 2915篇 |
内科学 | 4096篇 |
皮肤病学 | 499篇 |
神经病学 | 1687篇 |
特种医学 | 1262篇 |
外国民族医学 | 5篇 |
外科学 | 4043篇 |
综合类 | 4286篇 |
现状与发展 | 4篇 |
一般理论 | 3篇 |
预防医学 | 1846篇 |
眼科学 | 461篇 |
药学 | 2362篇 |
33篇 | |
中国医学 | 1229篇 |
肿瘤学 | 2072篇 |
出版年
2024年 | 97篇 |
2023年 | 429篇 |
2022年 | 1000篇 |
2021年 | 1368篇 |
2020年 | 1141篇 |
2019年 | 901篇 |
2018年 | 911篇 |
2017年 | 878篇 |
2016年 | 883篇 |
2015年 | 1252篇 |
2014年 | 1455篇 |
2013年 | 1663篇 |
2012年 | 2343篇 |
2011年 | 2360篇 |
2010年 | 1688篇 |
2009年 | 1401篇 |
2008年 | 1638篇 |
2007年 | 1593篇 |
2006年 | 1491篇 |
2005年 | 1289篇 |
2004年 | 1046篇 |
2003年 | 1026篇 |
2002年 | 819篇 |
2001年 | 482篇 |
2000年 | 327篇 |
1999年 | 231篇 |
1998年 | 168篇 |
1997年 | 146篇 |
1996年 | 120篇 |
1995年 | 100篇 |
1994年 | 101篇 |
1993年 | 64篇 |
1992年 | 73篇 |
1991年 | 61篇 |
1990年 | 46篇 |
1989年 | 41篇 |
1988年 | 32篇 |
1987年 | 38篇 |
1986年 | 44篇 |
1985年 | 40篇 |
1984年 | 28篇 |
1983年 | 23篇 |
1982年 | 24篇 |
1981年 | 20篇 |
1980年 | 19篇 |
1979年 | 21篇 |
1978年 | 11篇 |
1976年 | 10篇 |
1975年 | 8篇 |
1957年 | 7篇 |
排序方式: 共有10000条查询结果,搜索用时 21 毫秒
81.
目的:比较中国北方地区树木花粉、杂草花粉以及尘螨引起的变应性鼻炎(AR)患者的生活质量水平,伴随哮喘情况,探讨AR患者的生活质量与变应原血清特异性IgE的关系。方法:选取164例AR伴或不伴哮喘的成人患者,完成病史采集及变应原检查,并填写标准化鼻结膜炎生存质量调查问卷(RQLQ)。结果:中国北方地区AR患者中,树木花粉组及杂草花粉组的RQLQ总评分、日常活动评分、鼻部症状及眼部症状评分均显著高于尘螨组,生活质量更差。树木花粉组的哮喘比例明显低于尘螨组,而杂草花粉组的哮喘比例则与尘螨组无明显差异,且显著高于树木花粉组。尘螨及蒿属花粉过敏所致的AR患者的RQLQ评分与其变应原特异性IgE水平之间无明显相关性。结论:AR患者的生活质量评分受到变应原具体类型的影响,中国北方地区花粉过敏者发病时的生活质量比尘螨过敏者更差,但生活质量受损程度可能不受变应原特异性IgE水平的影响。不同花粉过敏所致鼻炎合并哮喘的比例不同,杂草花粉可能比树木花粉更容易诱发哮喘。 相似文献
82.
83.
84.
Yan Zhang Lu Qiao Wenping Ding Kai Wang Yuqiong Chen Liwei Wang 《CTS Clinical and Translational Science》2022,15(8):1926
Efforts to prolong thoracic paravertebral block (TPVB) analgesia include local anesthetic adjuvants, such as dexamethasone (Dex). Previous studies showed that both perineural (PN) and intravenous (i.v.) routes could prolong analgesia. As PN Dex is an off‐label use, anesthesiologists should be fully informed of the clinical differences, if any, on block duration. This study was designed to evaluate the two administration routes of Dex for duration of analgesia in TPVB. Ninety‐five patients scheduled for Ivor‐Lewis esophagectomy were randomized to receive TPVB (0.5% ropivacaine 15 ml), PN or i.v. Dex 8 mg. The primary end point was the duration of analgesia. The secondary end points included pain scores, analgesic consumption, adverse effects rate, and incidence of chronic pain at 3 months postoperatively. The PN‐Dex group showed better analgesic effects than the i.v.‐Dex group (p < 0.05). Similarly, the visual analogue scale scores in patients at 2, 4, 8, and 12 h postoperatively were lower in the PN‐Dex group than the i.v.‐Dex group (p < 0.05). The analgesic consumption in both the PN‐Dex and i.v.‐Dex groups was significantly lower than that in the control group (p < 0.05). Regarding the incidence of chronic pain, regardless of route, Dex decreased the incidence of chronic postsurgical pain and neuropathic pain at 3 months after surgery (p < 0.05), but there were no clinical differences between the i.v.‐Dex and PN‐Dex groups. Perineural dexamethasone improved the magnitude and duration of analgesia compared to that of the i.v.‐Dex group in TPVB in Ivor‐Lewis esophagectomy. However, there were no clinically significant differences between the two groups in the incidence of chronic pain. Study Highlights WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC? Both perineural (PN) and intravenous (i.v.) dexamethasone (Dex) could prolong the duration of a nerve block, but the superiority of either route is still inconclusive. WHAT QUESTION DID THIS STUDY ADDRESS? The study investigated the effects of the two routes of Dex added to ropivacaine on analgesic effects of thoracic paravertebral block in patients undergoing Ivor‐Lewis esophagectomy. WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE? These results extend the knowledge of the superior analgesic effect of Dex for the management of perioperative pain in the setting of Ivor‐Lewis Esophagectomy. HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE? Because PN Dex is an off‐label use, our study conformed the safety of Dex as PN adjuvants and extended its application field in clinical work. 相似文献
85.
Ming Bai Meng Wang Ting Deng Yuxian Bai Kai Zang Zhanhui Miao Wenlin Gai Liangzhi Xie Yi Ba 《癌症生物学与医学(英文版)》2022,19(3):358-369
Objective: The mainstay treatment of esophageal squamous cell carcinoma(ESCC) involves chemotherapy and immunotherapy. However, alternative therapies are required for patients who are refractory or intolerant to existing therapies.Methods: In this single-arm, multicenter, open-label phase Ib study, 30 patients received an intravenous infusion of SCT200, an antiepidermal growth factor receptor(EGFR) monoclonal antibody, 6.0 mg/kg once a week for 6 weeks, followed by 8.0 mg/kg once every 2 weeks u... 相似文献
86.
Ruo-Peng Liang Xiao-Xue Zhang Jie Zhao Qin-Wei Lu Rong-Tao Zhu Wei-Jie Wang Jian Li Kai Bo Chi-Xian Zhang Yu-Ling Sun 《World journal of gastroenterology : WJG》2022,28(27):3435
BACKGROUNDHepatocellular carcinoma (HCC) exhibits high invasiveness and mortality rates, and the molecular mechanisms of HCC have gained increasing research interest. The abnormal DNA damage response has long been recognized as one of the important factors for tumor occurrence and development. Recent studies have shown the potential of the protein RING finger and WD repeat domain 3 (RFWD3) that positively regulates p53 stability in response to DNA damage as a therapeutic target in cancers. AIMTo investigate the relationship between HCC and RFWD3 in vitro and in vivo and explored the underlying molecular signalling transduction pathways. METHODS RFWD3 gene expression was analyzed in HCC tissues and adjacent normal tissues. Lentivirus was used to stably knockdown RFWD3 expression in HCC cell lines. After verifying the silencing efficiency, Celigo/cell cycle/apoptosis and MTT assays were used to evaluate cell proliferation and apoptosis. Subsequently, cell migration and invasion were assessed by wound healing and transwell assays. In addition, transduced cells were implanted subcutaneously and injected into the tail vein of nude mice to observe tumor growth and metastasis. Next, we used lentiviral-mediated rescue of RFWD3 shRNA to verify the phenotype. Finally, the microarray, ingenuity pathway analysis, and western blot analysis were used to analyze the regulatory network underlying HCC. RESULTSCompared with adjacent tissues, RFWD3 expression levels were significantly higher in clinical HCC tissues and correlated with tumor size and TNM stage (P < 0.05), which indicated a poor prognosis state. RFWD3 silencing in BEL-7404 and HCC-LM3 cells increased apoptosis, decreased growth, and inhibited the migration in shRNAi cells compared with those in shCtrl cells (P < 0.05). Furthermore, the in vitro results were supported by the findings of the in vivo experiments with the reduction of tumor cell invasion and migration. Moreover, the rescue of RFWD3 shRNAi resulted in the resumption of invasion and metastasis in HCC cell lines. Finally, gene expression profiling and subsequent experimental verification revealed that RFWD3 might influence the proliferation and metastasis of HCC via the Wnt/β-catenin signalling pathway.CONCLUSIONWe provide evidence for the expression and function of RFWD3 in HCC. RFWD3 affects the prognosis, proliferation, invasion, and metastasis of HCC by regulating the Wnt/β-catenin signalling pathway. 相似文献
87.
The periosteum, a highly vascularized thin tissue, has excellent osteogenic and bone regenerative abilities. The generation of periosteum-mimicking tissue has become a novel strategy for bone defect repair and regeneration, especially in critical-sized bone defects caused by trauma and bone tumor resection. Here, we utilized a bone morphogenetic protein-2(BMP-2)-loaded scaffold to create periosteum-like tissue(PT) in vivo, mimicking the mesenchymal condensation during native long bone developmen... 相似文献
88.
??OBJECTIVE To establish a capillary zone electrophoresis(CZE)-based method for charge heterogeneity analysis of IgG2 monoclonal antibody. METHODS The concentrations of TETA and EACA, pH of separation buffer and temperature of capillary were optimized, to obtain a method which can efficiently separate the charge variants of IgG2 mabs. The reproducibility and repeatability of the optimized CZE method were validated and a battery of mabs were evaluated. RESULTS The separation effect was significantly influenced by TETA/EACA concentration, pH and separation temperature. Through a series of optimization, a CZE method which showed good resolution and precision(RSD of area percentage was below 3.0% was established and the method parameters were as below: 400 mmol??L-1 EACA/0.05% TETA, pH 6.2, separation under 30 kV voltage at 35 ??. This method was also suitable for IgG1 and IgG4 mabscharge heterogeneity analysis. Based on the specific electrophorogram and migration time, it could also be used as an identification method for monoclonal antibodies. CONCLUSION The optimized CZE method can efficiently separate the charge variants of IgG2 mabs and shows good precision and specificity, which can be used to analyze the charge heterogeneity and identification of monoclonal antibodies. 相似文献
89.
目的:研究当归红芪超滤膜提取物(UFE-AH)对阿霉素所致心肌细胞凋亡的影响.方法:取新生1~2d的Wistar乳鼠,用差速贴壁法原代提取心肌细胞,调整细胞密度1×106/mL,于37℃5% CO2培养箱中密闭培养48 h.用2.5 mg·L-1阿霉素作用于心肌细胞24 h成功建立心肌细胞凋亡模型.实验分5组:正常对照组、阿霉素组(2.5 mg·L-1)、UFE-AH低、中、高剂量干预组(阿霉素造模前2h预先分别给予3.75,7.5,15 g·L-1当归红芪超滤膜提取物).四氮唑蓝(MTT)法检测各组细胞生长抑制率,单细胞凝胶电泳检测DNA损伤,Western blot(蛋白印迹法)检测B淋巴细胞瘤-2蛋白(Bel-2),Bel-2相关X蛋白(Bax)表达水平.结果:与正常组相比,阿霉素组心肌细胞生长抑制率明显增加,且头部DNA含量占总含量的百分数(HDNA%),尾部DNA含量占总含量的百分数(TDNA%),尾长(TL),尾短(TM),尾距(OTM)均明显升高,Bcl-2蛋白表达水平下降、Bax表达水平升高,均有统计学意义(P<0.01);UFE-AH干预组的心肌细胞生长抑制率明显降低,且HDNA%,TDNA%,TL,TM,OTM数值均降低,Bcl-2蛋白表达水平上调,Bax表达水平下调,有显著性差异(P<0.01).结论:UFE-AH可减轻阿霉素对心肌细胞DNA的损伤,上调Bcl-2/Bax而抑制心肌细胞的凋亡,具有抗心肌细胞凋亡的保护作用. 相似文献
90.
肱二头肌长头肌腱(10ngheadofbicepsbrachiiIelq(10n,LHBT)损伤主要起因于年轻患者急性创伤和老年患者的退行性病变,以后者为主,典型患者以往有肩关节过度活动史,尤其是肩外展动作。二头肌腱腱鞘是盂肱关节滑膜的延续并且与肩袖紧密相连,LHBT损伤常可引起周围相关结构的病变,例如肩袖损伤、肩峰下碰撞、上盂唇前后病变等,后者可继发加重LHBT病变,引起肩前区永久性疼痛、肩关节功能障碍口。患者专科检查时在结节问沟通常伴有明显压痛,疼痛在患侧臂外展伸直时加重。LBHT损伤的诊断除依赖病史和体格检查外,辅助检查尤为重要,包括x线片、核磁、超声等。x线片仅在晚期出现肌腱伴有钙化或盂肱间隙明显减少等时才有一定价值;国外有报道超声诊断LBHT损伤的敏感性达88%,特异性98%,对于肌腱全层撕裂、部分撕裂、肌腱等病变尤其敏感。MRI诊断价值一般, 相似文献