全文获取类型
收费全文 | 35029篇 |
免费 | 3555篇 |
国内免费 | 2165篇 |
专业分类
耳鼻咽喉 | 466篇 |
儿科学 | 852篇 |
妇产科学 | 172篇 |
基础医学 | 2199篇 |
口腔科学 | 690篇 |
临床医学 | 3860篇 |
内科学 | 3048篇 |
皮肤病学 | 275篇 |
神经病学 | 833篇 |
特种医学 | 1445篇 |
外科学 | 3103篇 |
综合类 | 10145篇 |
现状与发展 | 5篇 |
预防医学 | 4220篇 |
眼科学 | 461篇 |
药学 | 4104篇 |
55篇 | |
中国医学 | 3396篇 |
肿瘤学 | 1420篇 |
出版年
2024年 | 180篇 |
2023年 | 421篇 |
2022年 | 1217篇 |
2021年 | 1472篇 |
2020年 | 1315篇 |
2019年 | 698篇 |
2018年 | 683篇 |
2017年 | 1005篇 |
2016年 | 771篇 |
2015年 | 1389篇 |
2014年 | 1757篇 |
2013年 | 2241篇 |
2012年 | 3277篇 |
2011年 | 3336篇 |
2010年 | 3119篇 |
2009年 | 2840篇 |
2008年 | 2943篇 |
2007年 | 2676篇 |
2006年 | 2406篇 |
2005年 | 1903篇 |
2004年 | 1360篇 |
2003年 | 1131篇 |
2002年 | 815篇 |
2001年 | 722篇 |
2000年 | 588篇 |
1999年 | 197篇 |
1998年 | 50篇 |
1997年 | 37篇 |
1996年 | 42篇 |
1995年 | 33篇 |
1994年 | 23篇 |
1993年 | 21篇 |
1992年 | 14篇 |
1991年 | 13篇 |
1990年 | 9篇 |
1989年 | 5篇 |
1988年 | 5篇 |
1987年 | 9篇 |
1986年 | 2篇 |
1985年 | 3篇 |
1984年 | 9篇 |
1983年 | 4篇 |
1982年 | 1篇 |
1955年 | 2篇 |
1954年 | 1篇 |
1953年 | 1篇 |
1950年 | 2篇 |
1948年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Objective To investigate the effect and mechanism by which PPARγ ligand, rosiglitasone, regulates the expression of CD40 and intercellular adhesion molecule 1 (ICAM-1) in the rat peritoneal mesothelial cells (RPMCs) induced by lipopolysaccharide (LPS). Methods RPMCs were harvested from Sprague-Dawley rat peritoneal cavity and maintained under defined in vitro conditions. The cells were randomly divided into groups as follows: medium, LPS (5 mg/L), LPS (5 mg/L)+BAY11-7085(5 μmol/L, NF-κB inhibitor), rosiglitazone (10 μmol/L or 20 μmol/L, peroxisome proliferator-activated receptor γ activator), LPS (5 mg/L)+rosiglitazone (10 μmol/L)+GW9662 (3 μmol/L, peroxisome proliferator-aetivatcd receptor γ antagonist), and LPS (5 mg/L)+vehicle (DMSO 0.2 ml/L). The expressions of CD40 and ICAM-1 RNA in RPMCs were examined by RT-PCR after 3 hour treatment, and the protein expressions of CD40, ICAM-1, p-NF-κB p65 and p-IκBα were examined by Western blot or immunofluorescence after 24 hour treatment. Results Following treatment with LPS, both the expressions of CD40 and ICAM-1 protein in RPMCs were up-regulated significantly (P<0.05), and the phosphoralation of p65 was increased greatly (1.10±0.17 vs 0.55±0.06, P<0.05). BAY11-7085 (5 μmol/L) significantly decreased the protein expression of p-p65 (0.22±0.11 vs 1.10±0.17, P<0.01), CD40 (0.34±0.02 vs 0.50±0.06, P<0.05) and ICAM-1 (0.35±0.16 vs 0.74±0.03, P<0.05). Pretreated with rosiglitazone for 3 h then added with LPS for 1 h, the levels of p-p65, CD40 and ICAM-1 in RPMCs were significantly decreased compared with those of LPS group (0.77±0.08 vs 0.90±0.10, P相似文献
62.
自身免疫性感音神经性聋豚鼠的子代内耳生理功能研究 总被引:4,自引:4,他引:0
目的 :观察自身免疫性感音神经性聋 (ASHL)母豚鼠所产子代内耳生理功能的变化 ,探讨针对内耳的自身免疫因素对子代内耳生理功能的影响及其改变特点。方法 :同种内耳抗原 (CIEAg)持续免疫孕豚鼠 ,采用耳蜗电图 (记录cAP、CM )和眼震电图仪 (记录自发性眼震和冷热空气试验 )测试母鼠和子鼠的听觉和前庭功能 ,并检测血清特异性体液免疫反应。结果 :ASHL模型母豚鼠所产子鼠血清中发现有特异性抗体水平升高 ,部分 (3 /9)出现听觉损伤。非ASHL母鼠和对照组母鼠所产子代未见明显异常。结论 :ASHL雌鼠所产子代可出现感音神经性聋 ,其内耳损伤和功能障碍极可能与针对内耳组织的自身免疫反应 (尤其是体液免疫 )有关 ,从而提示内耳自身免疫因素可能为部分先天性非遗传性感音神经性聋的病因之一。 相似文献
63.
婴儿巨细胞病毒性肝炎(下) 总被引:6,自引:0,他引:6
实验室检查主要包括诊断CMV感染和肝功能检查两方面。一、CMV感染的实验室检查实验室检查是诊断CMV感染和判明抗CMV治疗效果的基础,因此无论采用何种方法,必须试剂可靠,操作严格,结果可信。实验室检查的方法有以下几种。(一)病毒学检测1.显微镜下检测病毒颗粒和包涵体:在电镜下检查病毒,除能见到完整的病毒颗粒外,还可发现致密体等不完整的病毒颗粒。加用特异性抗CMV单抗后,能提高阳性检出率。但是此法不仅需要昂贵的电镜设备,阳性率也不高,已很少用于研究,更难作为常规检查。显微镜下寻找包涵体,阳性率也不高,且在很多产毒性感染时也… 相似文献
64.
目的 检测脂多糖作用于树突状细胞前后TLR2、3、4基因的表达情况。方法 从外周血分离单核细胞,加入rhGM-CSF及rhIL-4,培养的第6天,实验组加入脂多糖刺激24h,对照组不加。分别提取细胞总RNA,行半定量RT-PCR,产物进行琼脂糖凝胶电泳分析。结果 单核细胞经GM-CSF及IL-4诱导7d后的DC表达较高水平TLR2、3、4。脂多糖刺激24h后,TLR2、3、4表达下降,TLR4几乎测不到。结论 树突状细胞在受脂多糖刺激前后TLRs的表达有显著变化,推测和它的功能成熟有关。 相似文献
65.
Visfatin was expressed in rat anti mouse islets,as well as in MIN6 cells. The visfatin expression was affected by various concentrations of environmental glucose (5.5 and 33.3 mmoL/L) and palmitate(0.5 mmol/L). As compared with low-level glucose medium (5.5 mmol/L, 1.0±0.11) , visfatin expression increased in media with high glucose and palmitate (1.32 ±0. 18, 1. 33±0. 15,1.72±0.27, all P<0. 05). The result suggests that visfatin seems to be involved in the regulation of insulin secretion. 相似文献
66.
67.
糖尿病腹膜透析患者胰岛素治疗方案探讨 总被引:7,自引:0,他引:7
目的探讨糖尿病腹膜透析(CAPD)患者合理的胰岛素应用方法.方法采用横断面研究方法调查所有接受CAPD治疗至少6个月以上的糖尿病肾病患者的胰岛素使用方案及血糖控制情况.并在横断面研究的基础上,动态观察24例新收的糖尿病CAPD患者透析前、后胰岛素的使用方法、剂量调整方案及血糖控制情况.结果2002年6月至2002年12月间共25例2型糖尿病CAPD患者,其中腹腔内注射胰岛素(IP)6人,皮下注射胰岛素(SC)9人,腹腔和皮下联合应用(IP SC)7人.①空腹血糖、糖化血红蛋白、透析液糖总负荷量、透析液平均糖浓度、透析剂量在IP、SC、IP SC三组间差异均无显著性,(P>0.05);②与IP及IP SC组相比,SC组胰岛素用量明显减少,(P<0.05);③腹膜炎的总发生率为1次/每15患者月,明显高于同期非糖尿病腹膜透析患者的腹膜炎发生率(1次/每48患者月),(P<0.01);④动态观察24例新收的糖尿病CAPD患者,胰岛素剂量较透析前平均增加了(0.33±0.23)倍.透析后调整的胰岛素实际增加量与理论预测增加量差异无显著性,(P>0.05).患者血糖控制良好,平均为(5.81±1.22)mmol/L.结论皮下注射胰岛素是有效控制糖尿病CAPD患者血糖水平的适当途径.腹膜透析后,可在原有皮下应用胰岛素方案的基础上,参照糖吸收量计算需增加的胰岛素用量适当增减胰岛素,能有效控制血糖. 相似文献
68.
Objective To investigate whether low-protein diet has protective effect on the progression of renal interstitial fibrosis in rats with cyclosporine A (CsA)-induced nephropathy. Methods Eighteen male Sprague-Dawley rats were randomly divided into three groups (6 rats in each group). The rats in control group (C group) received common diet; in model group (M group) low-salt diet; in intervention group (Ⅰ group) low-salt and low-protein diet. After diet adaptation period of one week, the rats in C group received subcutaneous injection of olive oil 1 mg/kg daily for 5 weeks, while M group and Ⅰ group subcutaneous injection of CsA (diluted into 25 g/L with olive oil) 1 ml/kg for 5 weeks. All the rats were sacrificed at the end of the 5th week. The food-intake and body weight were measured daily. The creatinine clearance (Ccr) was examined before rats were sacrificed. The semi-quantitative pathological analysis on kidney sections was performed. The mRNA and protein expression of transforming growth factor-β1 (TGF-βI) and type Ⅰ collagen (Col Ⅰ) in kidney tissue was determined with real time PCR and immunohistochemical staining, respectively. Results The food-intake and body weight of rats in M and I groups were significantly lower than those in C group (P<0.05). Compared with C group, the Ccr levels in M and Ⅰ groups were significantly reduced [(0.65±0.15) ml/min, (0.40+0.13) ml/min vs (1.55±0.29) ml/min, P<0.05], the relative fibrosis areas of kidney interstitium in M and I groups were significantly increased (3.60%±0.46%, 3.26%±0.75% vs 0.44%±0.24%, P<0.05), the mRNA and protein expression of TGF-β1 in M and I group was significantly up-regulated (by 2.6 and 3.1 times in mRNA and by 1.5 and 1.6 times in protein, respectively, P<0.05), and the mRNA and protein expression of Col Ⅰ in M and I groups was also significantly up-regulated (by 3.0 and 3.5 times in mRNA and by 2.3 and 2.1 times in protein, respectively, P<0.05). There were no significant differences between M and I groups in every parameters above-mentioned except the rat body weight and Ccr. Both the body weight and Ccr in Ⅰ group were significantly lower than those in M group (P<0.05). Compared with C group, the urine osmotic pressure in M group and in I group were deceased (for M group, P>0.05; for I group, P<0.05). Compared with C group, the serum cholesterol levels in M and I groups were significantly increased (P<0.05), and the serum phosphorus level in I group was significantly decreased (P<0.05). The levels of serum albumin and serum calcium of all three groups had no statistical differences (P>0.05). Conclusion Low-protein diet has no renoprutective effects on the rat model of cyclosporin A nephropathy, on the contrary, may induce body weight loss. 相似文献
69.
骨髓间充质干细胞促进骨-肌腱结合部愈合的初步观察 总被引:3,自引:0,他引:3
[目的]观察骨髓间充质干细胞对骨-肌腱结合部愈合的影响.[方法]采用骨髓穿刺、全骨髓培养法获取兔骨髓间充质干细胞.36只18周龄新西兰大白兔随机分为2组,实验组将骨髓间充质干细胞与Pluronic F-127载体材料结合后,植入兔髌骨部分切除模型,对照组只进行手术,不植入细胞.在术后6、12、18周进行X线片、大体和组织学观察评估.[结果]X线片显示术后6、12、18周实验组骨-肌腱结合部新生骨面积显著大于对照组(P<0.01).大体观察可见实验组骨-腱结合部愈合较早.HE染色显示实验组术后6周有大量的纤维母细胞和类软骨细胞增生,并可见新骨形成;12周,髌腱与松质骨接触面软骨细胞移行带形成;18周,纤维软骨移行带排列更有序.Safranin 0染色显示实验组术后6周,基质染色较深,部分骨-腱结合处可见相对浓染区;12周,基质染色范围明显减少,沿类软骨细胞走行分布;18周,类软骨细胞集中的区域染色较12周有所减退.组织学检查显示实验组术后6、12、18周骨-腱结合部组织愈合明显,较对照组迅速.[结论]骨髓间充质干细胞可以促进骨-肌腱结合部细胞增生,促进其早期愈合. 相似文献
70.
目的 探讨肺炎衣原体(Chlamydia pneumoniae)感染在多发性硬化(MS)发病和进展中的作用和致病机制。方法 选取急性期MS患者31例,缓解期MS患者28例及其他神经系统疾病患者30例,健康对照者30名,应用酶联免疫吸附试验测定患者和对照者血清及脑脊液中肺炎衣原体IgG和IgM抗体水平。结果 急性期MS组、缓解期MS组、其他神经系统疾病组和健康对照组的肺炎衣原体血清IgG分别为48.4%、35.7%、30.0%、23.3%;4组IgM抗体效价分别为12.9%、14.3%、20.0%、10.0%,总体比较差异无统计学意义(P〉0.05);急性期MS组与其他神经系统疾病组的脑脊液IgG和IgM抗体效价分别为0、6.7%和0、0,差异无统计学意义(P〉0.05)。结论 肺炎衣原体的感染或重复感染与MS发病相关不紧密,可能仅为MS的伴随感染。 相似文献