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991.
This study sought to prepare a self-microemulsion drug delivery system containing zingerone (Z-SMEDDS) to improve the low oral bioavailability of zingerone and anti-tumor effect. Z-SMEDDS was characterized by particle size, zeta potential and encapsulation efficiency, while its pharmacokinetics and anti-tumor effects were also evaluated. Z-SMEDDS had stable physicochemical properties, including average particle size of 17.29 ± 0.07 nm, the zeta potential of -22.81 ± 0.29 mV, and the encapsulation efficiency of 97.96% ± 0.02%. In vitro release studies have shown the release of zingerone released by Z-SMEDDS was significantly higher than free zingerone in different release media. The relative oral bioavailability of Z-SMEDDS was 7.63 times compared with free drug. Meanwhile, the half inhibitory concentration (IC50)of Z-SMEDDS and free zingerone was 8.45 μg/mL and 13.30 μg/mL, respectively on HepG2. This study may provide a preliminary basis for further clinical research and application of Z-SMEDDS.  相似文献   
992.
993.
Rectal cancer is a common malignant tumor of the digestive tract, with a high incidence and high mortality. This study aimed to identify the potential biomarkers and therapeutic targets for rectal adenocarcinoma (RAC) metastasis. The expression profiling of RAC patients with metastasis and RAC patients without metastasis was downloaded from The Cancer Genome Atlas (TCGA) database. The datasets were used to identify the genes associated with RAC metastasis. Fifty up‐regulated genes and seventeen down‐regulated genes were identified in the primary tumor loci of RAC metastasis compared with non‐metastasis. Sixty‐seven dysregulated gens were conducted to construct the protein–protein network, and CCND3 was the hub protein. The dysregulated genes were significantly enriched in pancreatic secretion, cell adhesion molecules pathways, response to vitamin D of biological process, and retinoid binding of molecular function. Quantitative real‐time polymerase chain reaction results demonstrated that CCND3, AQP3, PEG10, and RAB27B had the up‐regulated tendency in RAC metastasis; ADCY1 had the down‐regulated tendency in RAC metastasis. CCND3, AQP3, PEG10, RAB27B, and ADCY1 might play essential roles in the metastasis process of RAC through pancreatic secretion and cell adhesion molecules pathways. The five genes could be potential diagnosis biomarkers or therapeutic targets for RAC metastasis.  相似文献   
994.
The objective of the present study was to investigate the effects of genistein and equol on 3β-hydroxysteroid de- hydrogenase (3β-HSD) and 17β-hydroxysteroid dehydrogenase 3 (17β-HSD3) in human and rat testis microsomes. These enzymes (3β-HSD and 17β-HSD3), along with two others (cytochrome P450 side-chain cleavage enzyme and cytochrome P450 17α-hydroxylase/17-20 lyase), catalyze the reactions that convert the steroid cholesterol into the sex hormone testosterone. Genistein inhibited 3β-HSD activity (0.2 μmol L^-1 pregnenolone) with half-maximal inhibition or a half-maximal inhibitory concentration (IC50) of 87 ± 15 (human) and 636 ± 155 nmol L^-1 (rat). Genistein's mode of action on 3β-HSD activity was competitive for the substrate pregnenolonrge and noncompetitive for the cofactor NAD+. There was no difference in genistein's potency of 3β-HSD inhibition between intact rat Leydig cells and testis microsomes. In contrast to its potent inhibition of 3β-HSD, genistein had lesser effects on human and rat 17β-HSD3 (0.1 μmol L^-1 androstenedione), with an IC50 〉 100μmol L^-1. On the other hand, equol only inhibited human 3β-HSD by 42%, and had no effect on 3β-HSD and 17β-HSD3 in rat tissues. These observations imply that the ability of soy isoflavones to regulate androgen biosynthesis in Leydig cells is due in part to action on Leydig cell 3β- HSD activity. Given the increasing intake of soy-based food products and their potential effect on blood androgen levels, these findings are greatly relevant to public health.  相似文献   
995.
Zhang  Jun  Wang  Bo  Li  Rongke  Ge  Long  Chen  Kee-Hsin  Tian  Jinhui 《International urology and nephrology》2017,49(4):701-716
International Urology and Nephrology - The purpose of our study is to carry out a Bayesian network meta-analysis comparing the efficacy of different antimicrobial lock solutions (ALS) for...  相似文献   
996.
We report a large novel α-globin cluster deletion that we named –?–PG (NG_000006.1: g.93628_542759del450131), in a Chinese family. This large deletion is approximately 450?kb long, spanning from upstream of the PolR3k gene at the 5′ end to the RAB11FIP3 gene at the 3′ end of chromosome 16p13.3. This deletion removes all the globin distal regulatory elements as well as the whole α-globin gene cluster. Patients with heterozygous –?–PG/αα had red blood cell (RBC) indices consistent with α-thalassemia (α-thal) trait, but no apparent increase in a cancer tendency or mental disability, microcephaly, relative hypertelorism, unusual facies or genital anomalies.  相似文献   
997.
目的 探讨数字化技术在半侧颜面萎缩畸形治疗中皮瓣设计选择的临床应用价值. 方法 半侧颜面萎缩侧患者7例,术前行CT血管成像扫描,应用Mimics 14.3软件对畸形部位进行三维重建,设计修复所需要的骨组织、软组织块.根据供区、受区的血管直径,选择背阔肌皮瓣4例、股前外侧皮瓣3例,采用快速成型打印缺损块,根据设计方案完成手术. 结果 移植7例皮瓣成活,修复半面萎缩外形良好,术后随访3年,皮瓣外观良好,效果确切. 结论 采用数字化技术进行术前模拟设计手术,可前瞻性了解手术效果,能够精确切取皮瓣范围,并可以避免术中血管吻合时受区、供区不匹配现象,保证了皮瓣的成活,具有实用价值.  相似文献   
998.
背景:肥大细胞糜蛋白酶在烧伤创面表达的研究较少。 目的:观察肥大细胞糜蛋白酶是否存在于烫伤创面以及深Ⅱ度烫伤后不同时间点的表达变化。 方法:应用75 ℃的水接触仓鼠背部皮肤12 s制备深Ⅱ度烫伤创面(病理组织学证实)。分别于烫伤前及烫伤后1,3,7,14 d取烫伤组织进行试验。 结果与结论:实时定量RT-PCR及放射免疫 检测结果显示烫伤后创面组织中糜蛋白酶mRNA表达量和活性均有所增高,在烫伤后第3天最高。表明肥大细胞糜蛋白酶在烧伤创面有所表达,并可能参与了烧伤损伤愈合过程。  相似文献   
999.
AIM: To evaluate the effects of the various methods of small bowel preparation on the quality of visualization of the small bowel and the gastrointestinal transit time of capsule endoscopy (CE). METHODS: Ninety patients referred for CE were prospectively randomized to three equal groups according to the preparation used: (a) a control group, in which patients were requested to drink 1 L of clear liquids only, 12 h before the examination; (b) a purgative group, in which patients were requested to ingest 1 L of a polyethylene glycol (PEG)/electrolyte solution only, 12 h before the examination; or (c) a purgative combined with simethicone group (P-S group), in which patients were requested to ingest 1 L of PEG, 12 h before the examination, and 300 mg of simethicone, 20 min before the examination. Effects of the different bowel preparations on the gastric transit time (GTT), small bowel transit time (SBTT), examination completion rate, quality of images of the entire small intestine, and cleansing of the proximal small bowel and distal ileum were evaluated. RESULTS: The number of patients with "adequate" cleansing of the entire small intestine was 17 in the P-S group, 12 in the purgative group, and seven in the control group (P= 0.002). The P-S group had significantly better image quality than the control group (P= 0.001). The P-S group had significantly better image quality for the proximal small bowel (segment A [Seg A]) than the control group (P= 0.0001). Both the P-S group (P= 0.0001) and the purgative group (P= 0.0002) had significantly better image quality for the distal ileum (segment B [Seg B]) than the control group; the P-S group had significantly better image quality than the purgative group as well (P= 0.0121). Gastrointestinal transit time was not different among the three groups, nor was the examination completion rate. CONCLUSIONS: Purgative bowel cleansing combined with simethicone before CE improved the quality of imaging of the entire small bowel as well as the visualization of the mucosa in the proximal and distal small intestine.  相似文献   
1000.
527例溃疡性结肠炎临床与病理分析   总被引:19,自引:0,他引:19  
目的 评价临床、内镜及活检三者在溃疡性结肠炎(UC)诊断中的作用。方法 总结我院10年间经肠镜诊断为UC的病例,分析其临床、内镜表现及部分活检资料。结果 527例确诊为UC,其中误诊34例,结肠镜诊断正确率为93.9%。UC临床主要表现为腹泻(88%)、粘液脓血便(52%)。结肠镜表现以粘膜充血水肿(94%)、糜烂溃疡(75%)最多见,病变部位以直、乙结肠为主(51%),呈弥漫性、连续性分布。活检特征性表现为炎症程度重(49%),固有层弥漫性混合性炎细胞浸润(76%)、杯状细胞减少(71%)、隐窝扭曲(63%)、萎缩(47%)、隐窝炎(45%)、隐窝脓肿(36%)及绒毛状表面(39%)。结论 UC的诊断应强调临床、内镜及活检相结合。  相似文献   
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