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101.
A new drug-targeting system for CD13+ tumors has been developed, based on ultrasound-sensitive nanobubbles (NBs) and cell-permeable peptides (CPPs). Here, the CPP-doxorubicin conjugate (CPP-DOX) was entrapped in the asparagine–glycine–arginine (NGR) peptide modified NB (CPP-DOX/NGR-NB) and the penetration of CPP-DOX was temporally masked; local ultrasound stimulation could trigger the CPP-DOX release from NB and activate its penetration. The CPP-DOX/NGR-NBs had particle sizes of about 200?nm and drug entrapment efficiency larger than 90%. In vitro release results showed that over 85% of the encapsulated DOX or CPP-DOX would release from NBs in the presence of ultrasound, while less than 1.5% of that (30?min) without ultrasound. Cell experiments showed the higher cellular CPP-DOX uptake of CPP-DOX/NGR-NB among the various NB formulations in Human fibrosarcoma cells (HT-1080, CD13+). The CPP-DOX/NGR-NB with ultrasound treatment exhibited an increased cytotoxic activity than the one without ultrasound. In nude mice xenograft of HT-1080 cells, CPP-DOX/NGR-NB with ultrasound showed a higher tumor inhibition effect (3.1% of T/C%, day 24), longer median survival time (50 days) and excellent body safety compared with the normal DOX injection group. These results indicate that the constructed vesicle would be a promising drug delivery system for specific cancer treatment.  相似文献   
102.
The possibility of using commercial bayberry tannin (BT) from a Chinese source as a cross-linker and functional additive to develop soybean protein isolate (SPI)-based films was explored in this study by using the solvent casting method. In particular, the impacts of BT loading on the tensile strength, microstructure, thermal stability, water resistance and antioxidant capacity were fully investigated. The results reveal that SPI incorporated with BT yielded a phenolic–protein hybrid whose relevant films exhibited an improvement in tensile strength of around two times greater compared with native SPI as a result of the formed interactions and covalent cross-links, which could be proven using FTIR spectroscopy. The introduction of BT also led to the compact microstructure of SPI–BT films and enhanced the thermal stability, while the water vapor permeability was reduced compared with the control SPI film, especially at high loading content of tannin. Additionally, the use of BT significantly promoted the antioxidant capacity of the SPI-based films according to DPPH radical scavenging assay results. On this basis, Chinese bayberry tannin is considered a promising natural cross-linker and multifunctional additive that can be dedicated to developing protein-derived films with antioxidant activity for food packaging applications.  相似文献   
103.
目的 了解鼓室硬化和非鼓室硬化中耳炎患者在抗氧化物质超氧化物歧化酶(superoxide dismutase,SOD)、过氧化氢酶(catalnse,CAT)活性及过氧化反应产物丙二醛(malondialdehyde,MDA)浓度方面的差异,以进一步探讨鼓室硬化形成的机制.方法 回顾分析56例(56耳)中耳炎、中耳炎后遗症手术患者资料,分成两组:鼓室硬化组26耳,非鼓室硬化组30耳.测定所有患者血浆、红细胞中SOD、CAT活力及血浆、中耳组织中MDA浓度.结果 分析用秩和检验及相关分析.结果 两组血浆中MDA含量差异无统计学意义.鼓室硬化组中耳组织中MDA含量较高,差异有统计学意义(P<0.05).两组红细胞中SOD和CAT活力差异无统计学意义.鼓室硬化组血浆中的SOD和CAT活力较非鼓室硬化组低.差异有统计学意义.鼓室硬化组术前的听力平均值与其各检测项目所测得的MDA、SOD、CAT值均不存在相关(P>0.05).结论 鼓室硬化患者可能存在局部氧自由基浓度增高和抗氧化物质活性降低的情况.局部氧自由基浓度增高,血液抗氧化物质无法进入中耳组织,可能是形成鼓室硬化的病理基础.  相似文献   
104.
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   
105.
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   
106.

Purpose

Every year, almost one million individuals are diagnosed with hepatocellular carcinoma (HCC) worldwide and more than 690,000 patients die of it. At present, most therapeutic anti-HCC agents are not effective, which is due to the appearance of chemo-resistance and/or toxic side effects. Therefore, it is imperative to find novel more effective anti-HCC agents. Here, we evaluated the effect of giganteaside D (GD), an oleanolic acid saponin from P. scabiosaefolia, on the growth and apoptosis of HCC cells.

Methods and results

Using MTT and clonogenic assays, we found that GD exhibited a significant growth inhibitory effect on the HCC-derived cell lines HepG2 and Bel-7402. In addition, we found that GD induced mitochondria-mediated apoptosis in these HCC-derived cells, as indicated by a decreased mitochondrial potential, activation of Caspase-9 and Caspase-3, cleavage of PARP and release of Cytochrome C from the mitochondria. Besides, we found that GD stimulated the generation of reactive oxygen species (ROS) and that blockage of ROS attenuated the GD-induced mitochondria-mediated apoptosis. Additionally, we found that GD treatment led to a decrease in phosphorylated Erk (p-Erk) and triggered the generation of p-JNK, both components of the mitogen-activated protein kinase (MAPK) signaling pathway. Inhibition of Erk or JNK by specific inhibitors or siRNAs augmented or attenuated the cytotoxic and apoptotic effects of GD.

Conclusions

From our results we conclude that GD can induce ROS-mediated apoptosis in HCC-derived cells through the MAPK pathway. This observation may open up avenues to explore the future use of GD as a HCC chemotherapeutic agent.
  相似文献   
107.
108.
A systematic examination of the Chinese soft coral Dendronephthya sp. resulted in the isolation and characterization of 18 new cembranoid diterpenes, namely, dendronpholides A-R (2-19), along with 11-episinulariolide and an enantiomer of sandensolide. Their structures were determined through extensive spectroscopic (IR, MS, 2D NMR) data analyses and by comparison with those reported in literature. The cytotoxicity of several compounds against human tumor cell lines was also evaluated.  相似文献   
109.
AIM OF THE STUDY: Our previous results have shown one species of parasitic loranthus (Taxillus chinensis (DC.) Dancer) exhibits potent inhibition on fatty acid synthase (FAS) that is proposed to be a potential therapeutic target for treatment of obesity. However, the medicinal parasitic loranthus come from tens of plants of two families, the Loranthaceae and the Viscaceae. This study was carried out to figure out whether these parasitic loranthus from the two families have similar inhibitory ability on FAS, and whether the parasitic loranthus with potent inhibitory ability on FAS significantly reduce body weight of animal. MATERIALS AND METHODS: CD-1 mice were used to test the effects of samples on their body weight and food intake in 20 days. The reversible and irreversible inhibition on FAS was assayed to study the inhibitory ability of sixteen different medicinal plants from these two families, which were collected in nature. RESULTS: The reversible inhibitory ability of the extracts from the Loranthaceae was nearly 400-fold stronger than that from the Viscaceae. The species from the genus Taxillus Tieghem showed the best effect on FAS in both reversible and irreversible inhibition. Moreover, the difference in host plants did not affect markedly on the inhibitory ability of parasitic loranthus. The medicinal herb with high inhibitory ability on FAS significantly reduced the body weight and food intake of mice by oral administration. CONCLUSIONS: The medicinal herbs from the family Loranthaceae, rather than those from the family Viscaceae, should be suitable to apply as botanical sources of parasitic loranthus for weight control. The herbs from genus Taxillus Tieghem are the best.  相似文献   
110.
Yu X  Deng XH  Chao L  Yu HL  Liu WJ 《中华妇产科杂志》2008,43(3):213-217
目的 探讨冻融后移植的小鼠卵巢组织对促性腺激素的反应.方法 将36只性成熟雌性小白鼠随机分为新鲜移植组、冻融移植组和对照组,每组12只.新鲜移植组小鼠切除双侧卵巢,将卵巢切成小组织块,立即移植人双侧肾被膜下;冻融移植组小鼠切除双侧卵巢,将卵巢切成小组织块,采用玻璃化冷冻方法冷冻保存,2周后将冷冻卵巢组织复苏,移植入小鼠双侧肾被膜下.卵巢组织移植2周后,新鲜移植组和冻融移植组每组随机取6只小鼠应用7.5 IU人绝经期促性腺激素及10 IU绒毛膜促性腺激素,观察移植后的卵巢组织对促性腺激素的反应.同时应用免疫组化染色方法观察各组卵泡中卵泡刺激素受体的表达情况.结果 新鲜移植组、冻融移植组和对照组未应用促性腺激素小鼠卵巢组织内近成熟卵泡百分率分别为2.3%、2.3%和2.6%,应用促性腺激素小鼠卵巢组织内近成熟卵泡百分率分别为4.2%、4.0%和5.8%,各组内分别比较,差异均有统计学意义(P<0.05);新鲜移植组和冻融移植组与对照组比较,差异均元统计学意义(P>0.05).新鲜移植组、冻融移植组和对照组卵泡刺激素受体表达积分吸光度值在窦状卵泡中分别为9408±2777、9175±3093和8838±2064,在窦前卵泡中分别为4531±1903、4808±1386和5516±1136,各组间分别比较,差异均无统计学意义(P>0.05).结论 卵巢组织冷冻保存、复苏及移植过程未影响卵巢卵泡刺激素受体的表达,冻融后移植的小鼠卵巢组织对外源性促性腺激素的反应未受冷冻、复苏及移植等过程影响.  相似文献   
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