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51.
一测多评法测定复方人参片中的8种苷类成分   总被引:1,自引:1,他引:0  
目的 建立一测多评法(quantitative analysis single-marker,QAMS)测定复方人参片中8种苷类成分的含量。方法 采用Agilent XDB-C18色谱柱(4.6 mm×250 mm,5 μm),流动相水(A)-乙腈(B),梯度洗脱;体积流量1.0 mL·min-1;检测波长203 nm;柱温:25℃。以人参皂苷Rb1为内标,计算人参皂苷Rg1、人参皂苷Re、淫羊藿苷、人参皂苷Rc、人参皂苷Rb2、人参皂苷Rb3、人参皂苷Rd的相对校正因子,测定其含量。结果 8种成分在各自范围内线性关系良好(r ≥ 0.999 0),加样回收率为95.6%~104.4%,RSD为1.22%~2.73%,QAMS测定结果与外标法测定结果无显著性差异。结论 该法准确度、灵敏度高、专属性好、操作简单、重复性好。  相似文献   
52.
目的 研究雷公藤多苷片对高脂小鼠血脂的影响。方法 采用高血脂小鼠模型,通过小鼠尾静脉注射不同剂量(0.5,1.0,1.5 mg·kg-1·d-1)雷公藤多苷,测定不同时间段小鼠体质量和血清总胆固醇(total cholesterol,TC)、甘油三酯(totaltriglyceride,TG)、高密度脂蛋白胆固醇(high density lipoprotein cholesterol,HDL-C)、低密度脂蛋白胆固醇(low densitylipoprotein cholesterol,LDL-C)的含量及卵磷脂胆固醇酰基转移酶(lecithin cholesterol acyltransferase,LCAT)、肝脂酶(hepatic lipase,HL)和脂蛋白脂酶(lipoprotein lipase,LPL)的活性,研究雷公藤多苷对小鼠体质量、血脂代谢、动脉粥样硬化指数、肝脏LCAT水平等的影响。结果 给予高脂饲料后小鼠体质量和血脂显著升高(P<0.01),动脉粥样硬化指数显著升高(P<0.01),抗动脉粥样硬化指数显著下降(P<0.01)。注射雷公藤多苷能显著降低高血脂模型小鼠血清TC、TG和LDL-C,同时显著降低高脂饮食所导致的动脉粥样硬化指数升高。此外,雷公藤多苷片能显著提高血清LCAT水平和HL、LPL的活性。结论 雷公藤多苷片具有一定的降血脂功能,并能有效降低动脉粥样硬化的发生几率。  相似文献   
53.

Background

Digoxin is the oldest drug used in the pharmacotherapy of heart failure (HF). However, digoxin remains an important therapeutic option for patients with persistent symptoms of HF occurring despite the implementation of standard pharmacotherapy. Digoxin concentration serum (SCD) should equal 1–2 ng/ml. The aim of our study was to measure of SCD among the hospitalized patients as well as to determine the selected factors influencing the concentration of the digoxin in the blood.

Methods

The presented research was based on a retrospective analysis including 2149 patients treated with digoxin and hospitalized between 1980 and 2000. Was used for the determination of SCD automatic analyzer TDX ABBOTT GmbH – fluorescence polarization immunoassay (FPIA), with therapeutic range for digoxin of 0.8–2.0 ng/ml.

Results

Average SCD result in the study population was located within the therapeutic range and amounted 1.06 ng/ml (55.7% of patients). Statistically significant differences in digoxin level were observed depending on the way of medicine administration (p = 0.000001) and the daily amount (p = 0.001). Moreover, statistically significant differences in digoxin level were observed depending on sex (p = 0.00002).

Conclusions

An elevated level of digoxin was observed in the case of patients who received the medication both orally and intravenously, together with an increase in the daily amount of digoxin doses. It was confirmed that an elevated digoxin level occurs in the course of treatment in the case of women.  相似文献   
54.
目的 探究紫云英苷对膝关节骨性关节炎(KOA)大鼠的保护作用以及对JNK/p38MAPK信号通路的影响。方法 90只SD大鼠随机分为假手术组、模型组、塞来昔布组(18 mg/kg)、紫云英苷低(25 mg/kg)、中(50 mg/kg)、高(100 mg/kg)剂量组,每组15只。改良Huith法建立KOA模型,术后灌胃6周。游标卡尺测量大鼠膝关节直径,足趾容积仪测量大鼠足趾容积;ELISA法检测血清IL-1β、IL-6、TNF-α水平;HE染色观察膝关节软骨组织病理变化;ELISA法检测软骨组织TGF-β1、MMP-3水平;Western Blot法检测p-JNK、JNK、p-p38MAPK、p38MAPK蛋白表达。结果 与假手术组比较,模型组大鼠软骨组织表面被破坏,组织层变薄,细胞数量减少且排列紊乱,潮线被大量破坏;膝关节直径与足趾容积明显变大(P<0.05);血清中IL-1β、IL-6、TNF-α水平以及软骨组织中TGF-β1、MMP-3水平,p-JNK/JNK、p-38MAPK/p38MAPK比值显著升高(P<0.05)。与模型组比较,塞来昔布组与紫云英苷各剂量组软骨组织病变明显减轻;膝关节直径与足趾容积明显缩小(P<0.05);血清中IL-1β、IL-6、TNF-α水平以及软骨组织中TGF-β1、MMP-3水平,p-JNK/JNK、p-38MAPK/p38MAPK比值显著降低(P<0.05),且紫云英苷各剂量组间具有剂量效应(P<0.05);紫云英苷高剂量组与塞来昔布组比较差异无统计学意义(P>0.05)。结论 紫云英苷可能通过抑制JNK/p38MAPK信号通路激活,减轻炎症反应,改善KOA大鼠膝关节软骨组织损伤。  相似文献   
55.
HPLC测定桑叶中绿原酸、芦丁和木犀草苷含量   总被引:2,自引:2,他引:0  
目的建立同时测定桑叶中绿原酸、芦丁和木犀草苷含量的方法。方法样品用70%乙醇溶液提取,采用Phenomenex LunaC18色谱柱(4.6mm×250mm,5μm)分离;流动相:0.1%磷酸-乙腈,梯度洗脱;流速:1:0mL·min^-1;检测波长:348nm。结果绿原酸、芦丁、木犀草苷分别在3.048~152.4,1.059~52.96,1.437-71.85μg·mL一内具有良好的线性关系;加标回收率分别为100.4%,98.3%,98.7%;RSD分别为1.7%,2.0%,1.9%(n=9)。结论该方法简单易行,准确性和重复性好,可用于桑叶的质量控制。  相似文献   
56.
Bladder cancer is the second most prevalent malignancy in the genitourinary tract and remains a therapeutic challenge. In the search for new treatments, researchers have attempted to find compounds with low toxicity. With this goal in mind, Uncaria tomentosa is noteworthy because the bark and root of this species are widely used in traditional medicine and in adjuvant therapy for the treatment of numerous diseases. The objective of this study was to investigate the antitumor effect of one purified bioactive fraction of U. tomentosa bark on cell proliferation in two human bladder cancer cell lines, T24 and RT4. Quinovic acid glycosides purified fraction (QAPF) of U. tomentosa decreased the growth and viability of both T24 and RT4 cell lines. In T24 cells, QAPF induced apoptosis by activating caspase-3 and NF-κB. Further study showed that this fraction does not induce cell cycle arrest and does not alter PTEN and ERK levels. In conclusion, we demonstrated that QAPF of U. tomentosa has a potent inhibitory effect on the growth of human bladder cancer cell lines by inducing apoptosis through modulation of NF-κB, and we suggest that QAPF may become a potential therapeutic agent for the prevention and/or treatment of this cancer.  相似文献   
57.
目的:探讨肉苁蓉总苷( GCs)对阿尔茨海默病(AD)模型大鼠学习认知功能的影响及其作用机制。方法: 双侧脑室注射Aβ1-42 制备AD大鼠模型,连续给予模型大鼠不同剂量的GCs 腹腔注射20 d,Morris 水迷宫检测各 组大鼠空间学习记忆能力,尼氏染色观察海马CA1区细胞形态并计数正常锥体细胞;免疫组织化学测定脑组织突 触素( SYN)含量、酶联免疫吸附试验测定血清超氧化物歧化酶( SOD)和谷胱甘肽过氧化物酶( GSH-Px)活 性、丙二醛( MDA)的含量。结果:GCs 可明显缩短逃避潜伏期与上台前路程,明显增加目标象限时间百分比 与穿越平台次数;GCs 能提高海马CA1区锥体细胞的存活率,明显增加SYN蛋白的表达和提高SOD、GSH-Px 活 性,降低MDA的活性。结论:GCs 改善AD学习认知障碍的机制可能是通过减少自由基堆积、清除体内过多的 过氧化物,进而提高突触可塑性来改善学习认知功能。  相似文献   
58.
Phenylethanoid glycosides (PhGs) are generally water-soluble phenolic compounds that occur in many medicinal plants. Until June 2020, more than 572 PhGs have been isolated and identified. PhGs possess antibacterial, anticancer, antidiabetic, anti-inflammatory, antiobesity, antioxidant, antiviral, and neuroprotective properties. Despite these promising benefits, PhGs have failed to fulfill their therapeutic applications due to their poor bioavailability. The attempts to understand their metabolic pathways to improve their bioavailability are investigated. In this review article, we will first summarize the number of PhGs compounds which is not accurate in the literature. The latest information on the biological activities, structure–activity relationships, mechanisms, and especially the clinical applications of PhGs will be reviewed. The bioavailability of PhGs will be summarized and factors leading to the low bioavailability will be analyzed. Recent advances in methods such as bioenhancers and nanotechnology to improve the bioavailability of PhGs are also summarized. The existing scientific gaps of PhGs in knowledge are also discussed, highlighting research directions in the future.  相似文献   
59.
Esophageal adenocarcinoma (EAC) is a cancer characterized by rapidly rising incidence and poor survival, resulting in the need for new prevention and treatment options. We utilized two cranberry polyphenol extracts, one proanthocyanidin enriched (C-PAC) and a combination of anthocyanins, flavonoids, and glycosides (AFG) to assess inhibitory mechanisms utilizing premalignant Barrett’s esophagus (BE) and EAC derived cell lines. We employed reverse phase protein arrays (RPPA) and Western blots to examine cancer-associated pathways and specific signaling cascades modulated by C-PAC or AFG. Viability results show that C-PAC is more potent than AFG at inducing cell death in BE and EAC cell lines. Based on the RPPA results, C-PAC significantly modulated 37 and 69 proteins in JH-EsoAd1 (JHAD1) and OE19 EAC cells, respectively. AFG treatment significantly altered 49 proteins in both JHAD1 and OE19 cells. Bioinformatic analysis of RPPA results revealed many previously unidentified pathways as modulated by cranberry polyphenols including NOTCH signaling, immune response, and epithelial to mesenchymal transition. Collectively, these results provide new insight regarding mechanisms by which cranberry polyphenols exert cancer inhibitory effects targeting EAC, with implications for potential use of cranberry constituents as cancer preventive agents.  相似文献   
60.
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