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1.
From ancient times to the present-day animal venoms had been used as medicinal and therapeutic agents. Recently it has been reported that the scorpion venom is a potential source of active and therapeutic compounds to design potent drugs against variety of cancerous cells and other diseases. The current study aimed to evaluate the selective toxicity of Iranian Mesobuthus eupeus (IMe) crude venom as a potential source of anticancer compounds on cancerous CLL B-lymphocytes and normal lymphocytes. For this purpose, we isolated cancerous CLL B-lymphocytes and normal lymphocytes from chronic lymphocytic leukemia patients and healthy volunteers. Cancerous CLL B-lymphocytes and normal lymphocytes were treated with different concentration (0, 5, 10, 20, 40 and 80 µg/ml) of IMe crude venom for 12 hours and cytotoxicity, reactive oxygen species (ROS) production, collapse of mitochondrial membrane potential (MMP) and lysosomal membrane integrity were determined. The data demonstrated the significant cytotoxic effect of IMe crude venom on cancerous CLL B-lymphocytes, with a concentration value (IC50) that inhibits 50% of the cell viability of 60 µg/ ml after 12 h of incubation. MTT assay proved that the IMe crude venom is selectively toxic to cancerous CLL B-lymphocytes, and IMe crude venom induced selective cell death via activation of ROS formation and mitochondrial/lysosomal dysfunction. These finding showed that IMe crude venom has a selective mitochondrial/lysosomal-mediated cell death effect on cancerous CLL B-lymphocytes. Therefore, the IMe crude venom and its fractions may be promising in the future anticancer drug development for treatment of CLL and variety of cancers.  相似文献   
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Origanum species are mostly distributed around the Mediterranean, Euro‐Siberian, and Iran‐Siberian regions. Since time immemorial, the genus has popularly been used in Southern Europe, as well as on the American continent as a spice now known all over the world under the name “oregano” or “pizza‐spice.” Origanum plants are also employed to prepare bitter tinctures, wines, vermouths, beer, and kvass. The major components of Origanum essential oil are various terpenes, phenols, phenolic acids, and flavonoids with predominant occurrence of carvacrol and thymol (with reasonable amounts of p‐cymen and ‐terpinene) or of terpinene‐4‐ol, linalool, and sabinene hydrate. Many species of Origanum genus are used to treat kidney, digestive, nervous, and respiratory disorders, spasms, sore throat, diabetes, lean menstruation, hypertension, cold, insomnia, toothache, headache, epilepsy, urinary tract infections, etc. Origanum essential oil showed potent bioactivities owing to its major constituents' carvacrol, thymol, and monoterpenes. Several preclinical studies evidenced its pharmacological potential as antiproliferative or anticancer, antidiabetic, antihyperlipidemic, anti‐obesity, renoprotective, antiinflammatory, vasoprotective, cardioprotective, antinociceptive, insecticidal, and hepatoprotective properties. Its nanotechnological applications as a promising pharmaceutical in order to enhance the solubility, physicochemical stability, and the accumulation rate of its essential oils have been investigated. However, Origanum has been reported causing angioedema, perioral dermatitis, allergic reaction, inhibition of platelet aggregation, hypoglycemia, and abortion. Conclusive evidences are still required for its clinical applications against human medical conditions. Toxicity analyses and risk assessment will aid to its safe and efficacious application. In addition, elaborate structure–activity studies are needed to explore the potential use of Origanum‐derived phytochemicals as promising drug candidates.  相似文献   
4.
Accumulating evidence has indicated that corosolic acid exerts anti-diabetic, anti-obesity, anti-inflammatory, anti-hyperlipidemic and anti-viral effects. More importantly, corosolic acid has recently attracted much attention due to its anticancer properties and innocuous effects on normal cells. Furthermore, the increasing proportion of obese and/or diabetic populations has led to an epidemic of non-alcoholic fatty liver disease (NAFLD), which frequently progresses to hepatocellular carcinoma (HCC). Evidence has indicated that NAFLD is closely associated with the development of HCC and comprises a high risk factor. The present review summarizes the anticancer effects of corosolic acid in vitro and in vivo, and its related molecular mechanisms. It also describes the inhibitory effects of corosolic acid on the progression of NAFLD and its associated molecular mechanisms, providing guidance for future research on corosolic acid in NAFLD-related HCC prevention and treatment. To the best of our knowledge, a review of corosolic acid as an anticancer agent has not yet been reported. Due to its multitargeted activity in cancer cells, corosolic acid exerts anticancer effects when administered alone, and acts synergistically when administered with chemotherapeutic drugs, even in drug-resistant cells. In addition, as a novel tool to treat metabolic syndromes, corosolic acid uses the same mechanism in its action against cancer as that used in the progression of NAFLD-related HCC. Therefore, corosolic acid has been suggested as an agent for the prevention and treatment of NAFLD-related HCC.  相似文献   
5.
Since bromodomain containing 4 (brd4) has been considered as a prominent cancer target, numerous attempts have been made to develop potent brd4 bromodomain inhibitors. The present study provided a novel chemical scaffold which inhibited brd4 activity. Mid-throughput screening against brd4 bromodomain was performed using alpha-screen and homogeneous time-resolved fluorescence assays. Furthermore, cell cytotoxicity and xenograft assays were performed to examine if the compound was effective both in vitro and in vivo. As a result, it was revealed that compounds having naphthalene-1,4-dione scaffold inhibited the binding of bromodomain to acetylated histone. The compounds with naphthalene-1,4-dione had cytotoxic effects against the Ty82 cell line, a NUT midline carcinoma cell line, whose proliferation is dependent on brd4 activity. A10, one of the compounds with naphthalene-1,4-dione scaffold, also exhibited tumor growth inhibition effects in the xenograft assay. In addition, the compounds exhibited cytotoxic effects against gastric cancer cell lines which were resistant to I-BET-762, a BET bromodomain inhibitor. In conclusion, the novel scaffold to suppress brd4 activity was effective against cancer cells both in vitro and in vivo.  相似文献   
6.
Cell‐penetrating peptides (CPPs) have been considered as potential drug delivery vectors due to their remarkable membrane translocation capacity. However, lack of specificity and extreme systemic toxicity hamper their successful application for drug delivery. Here, we designed a new pH‐activatable CPP, LHHLLHHLHHLLHH‐NH2 (LH), by substitution of all lysines and two leucines of LKKLLKLLKKLLKL‐NH2 (LK) with histidines. As expected, histidine‐rich LH could be activated and penetrate into cells at pH 6.0, whereas its membrane transduction activity could be shielded at pH 7.4. In contrast, LK showed no obviously different cellular uptake at both pH conditions. Importantly, LH was significantly less cytotoxicity compared with LK at both pH values, suggesting a better safety for further application. In addition, after conjugation of camptothecin (CPT) with LH, this conjugate displayed remarkably pH‐dependent antitumor activity than free CPT and LK‐CPT. This study provides a new tumor pH‐responsive CPP with low toxicity for selective anticancer drug delivery.  相似文献   
7.
Targeting of the TRAIL-DR4/5 pathway was proposed as a promising approach for specific induction of apoptosis in cancer cells. Clinical trials, however, showed inadequate efficiency of TRAIL as a monotherapy. It is a widely held view that the application of multifunctional molecules or combination therapy may lead to substantial improvement. Here, we demonstrate the effectiveness and safety of a novel chimeric protein, AD-O51.4, which is a TRAIL equipped with positively charged VEGFA-derived effector peptides. The study was performed in multiple cancer cell line- and patient-derived xenografts. A pharmacokinetic profile was established in monkeys. AD-O51.4 strongly inhibits tumor growth, even leading to complete long-term tumor remission. Neither mice nor monkeys treated with AD-O51.4 demonstrate symptoms of drug toxicity. AD-O51.4 exhibits a satisfactory half-life in plasma and accumulates preferentially in tumors. The cellular mechanism of AD-O51.4 activity involves both cytotoxic effects in tumor cells and antiangiogenic effects on the endothelium. The presence of DRs in cancer cells is crucial for AD-O51.4-driven apoptosis execution. The TRAIL component of the fusion molecule serves as an apoptosis inducer and a cellular anchor for the effector peptides in TRAIL-sensitive and TRAIL-resistant cancer cells, respectively. The FADD-dependent pathway, however, seems to be not indispensable in death signal transduction; thus, AD-O51.4 is capable of bypassing the refractoriness of TRAIL. AD-O51.4-driven cell death, which exceeds TRAIL activity, is achieved due to the N-terminally fused polypeptide, containing VEGFA-derived effector peptides. The high anticancer efficiency of AD-O51.4 combined with its safety has led to the entry of AD-O51.4 into toxicological studies.  相似文献   
8.
Oxazines have brought much synthetic interest due to their extensive biological activities. These are the important category of heterocycles, which may be formally derived from benzene and its reduction products by convenient substitution of carbon (and hydrogen) atoms by nitrogen and oxygen. In the last few decades, oxazine derivatives have documented as worthy synthetic intermediates and also blessed with notable sedative, analgesic, anticonvulsant, antipyretic, antimicrobial, antitubercular, antimalarial, antioxidant, and anticancer activities. Nowadays, it is important to develop new classes of compounds with more effective mechanisms due to drug resistance activity in which the ability of drug to effectively treat disease can be reduced. The aim of the article is to collect and make a more generalized review on the synthesis of oxazine derivatives and their pharmaceutical and biological activities. We hope this review will provide ample references for the researchers concerned with azines in generally and oxazines in particular.  相似文献   
9.
目的:为研究人参皂苷20(S)-达玛-20,25-环氧-3β,12β,24α-三醇(24-OH-PD)对多种癌细胞的增殖抑制及诱导凋亡作用并探讨其作用机制。方法:采用噻唑蓝(MTT)比色法或Cell Titer Glo发光试验检测24-OH-PD在不同质量浓度(12. 5,25,50,100 mg·L~(-1)),不同作用时间(24,48,72 h)下对CCRF-CEM,Jeko-1,M14,MD-MBA-231癌细胞的增殖抑制作用,并与20(R)-Rg3,20(S)-Rh_2进行比较。采用流式细胞术检测24-OH-PD对以上4种癌细胞的凋亡诱导作用。采用药物设计平台薛定谔Maestro 6. 7软件对癌症相关的40种蛋白与24-OH-PD进行分子对接研究。结果:24-OH-PD对4种癌细胞均具有明显的细胞活性抑制作用,且具有时间、剂量依赖性。24-OH-PD对CCRF-CEM,Jeko-1,M14,MD-MBA-231细胞作用48 h时半抑制浓度(IC50)分别为25. 36,39. 29,21. 74,19. 35 mg·L~(-1),与20(S)-Rh_2作用效果相似(IC50分别为23. 35,65. 79,18. 95,19. 67 mg·L~(-1));远远强于20(R)-Rg3,仅对Jeko-1细胞有抑制作用(IC5049. 5 mg·L~(-1))。磷脂结合蛋白V/碘化吡啶(Annexin V/PI)双染实验结果显示,24-OH-PD对4种细胞均具有不同程度的促凋亡作用(P 0. 05),且具有剂量依赖关系。分子对接实验表明32个癌症相关蛋白中有11个能够与24-OH-PD对接成功,包括嘌呤核苷磷酸化酶(PNP),蛋白络氨酸激酶,蛋白激酶C(PKC),B淋巴细胞瘤基因-2(Bcl-2),B淋巴细胞瘤基因-xl (Bcl-xl),含半胱氨酸的天冬氨酸蛋白水解酶-8等,表明24-OH-PD的抗肿瘤作用可能与直接作用于这些蛋白相关。结论:人参皂苷24-OH-PD对CCRF-CEM,M14,MD-MBA-231,Jeko-1癌细胞具有增殖抑制作用,其机制可能与PNP,PKC等蛋白相关;同时24-OH-PD还具有诱导癌细胞凋亡的作用,机制可能与Bcl-2,Bcl-xl等蛋白相关。  相似文献   
10.
The continuous emergency of drug-resistant cancers and the low specificity of anticancer agents have been the major challenges in the control and treatment of cancer, making an urgent need to develop novel anticancer agents with high efficacy. Chalcones, precursors of flavonoids and isoflavonoids, exhibit structural heterogeneity and can act on various drug targets. Chalcones which demonstrated potential in vitro and in vivo activity against both drug-susceptible and drug-resistant cancers, are useful templates for the development of novel anticancer agents. Hybridization of chalcone moiety with other anticancer pharmacophores could provide the hybrids which have the potential to overcome drug resistance and improve the specificity, so it represents a promising strategy to develop novel anticancer agents. This review emphasizes the development, the mechanisms of action as well as structure-activity relationships of chalcone hybrids with potential therapeutic application for many cancers in recent 10 years.  相似文献   
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