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51.
Nine orally active novel artemisinin derivatives were prepared from artemisinin by four-step synthesis, and the compounds were evaluated in the rodent model using multidrug resistant Plasmodium yoelii nigeriensis. All of the compounds exhibited antimalarial activities with the ED50 ranging from 5.41 mg/kg–12.4 mg/kg. Among them, artemisinin derivative bearing N-(4-hydroxy-3-((4-phenylpiperazin-1-yl)methyl)phenyl) moiety (5f) was found to be the most active compound and was found to be three times more potent than artemisinin (ED50 16.4 mg/kg).  相似文献   
52.

Purpose

Although nail dynamization in femoral and tibial fractures is an effective method of promoting healing, its role beyond twelve weeks is still not clear. It is usually done two to three months following interlocking nailing. This study was done to evaluate the efficacy of late dynamization (after 12 weeks) and factors affecting union.

Materials and methods

In this retrospective study, thirty seven patients who underwent dynamization for reamed intramedullary interlocking nails of femur (18) and tibia (20) after twelve weeks from index surgery and with a minimum followup of six months were included. Fracture healing index was calculated using predynamization radiographs. Radiographic union was defined as osseous bridging of three cortices on followup radiographs. Dynamization failure was defined as fractures not showing progressive increase in callus on followup radiographs and those that required secondary intervention.

Results

Mean age of patients at time of injury was 35.92 years (range: 16–63) with males (86.8%) predominating. Mean time to dynamization from index surgery was 19.11 weeks (range-12–36). Thirty one fractures (81.5%) went onto union after dynamization of which twelve were femoral and nineteen were tibial fractures. Mean time to union after dynamization was 6 months. Communited fractures (6–21) showed poor results with delayed dynamization compared to other anatomical types which was statistically significant (P?=?0.05). Predynamization FHI of more than 1.18 had 83% sensitivity and 72% specificity in predicting fracture healing after dynamization.

Conclusion

Late dynamization is still beneficial in promoting healing in femoral and tibial fractures. Communited fractures showed poor results with dynamization. Predynamization FHI was an important predictor of fracture healing.  相似文献   
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Mannich bases of gatifloxacin were synthesized by reacting them with formaldehyde and several isatin derivatives. Their chemical structures have been confirmed by means of their IR, 1H-NMR data and by elemental analysis. The compounds were tested in-vitro against a panel of 58 human tumour cell lines derived from nine neoplastic diseases. Among them compound 1-cyclopropyl-6-fluoro-8-methoxy-1,4-dihydro-4-oxo-7[[N4-(3'-sulphadoximino)-1'-(5-bromoisatinyl) methyl]-3-methyl N1-piperazinyl]-3-quinoline carboxylic acid (6) emerged as a potent anticancer agent being more active than standard DNA topoisomerase II inhibitor, etoposide against 30 cancer cell lines.  相似文献   
55.
BACKGROUND: Dietary cholesterol plays an important role in development of atherogenesis and cardiovascular disease. We explored the lipemic-oxidative injury in the hypercholesterolemic atherogenic animals. The effects of eicosapentaenoic acid (EPA), dl-alpha-lipoic acid (LA) and eicosapentaenoate-lipoate derivative (EPA-LA) were tested for their efficacy in controlling the atherogenic disturbances. METHODS: Four groups of male Wistar rats were fed with a high cholesterol diet (rat chow supplemented with 4% cholesterol and 1% cholic acid; HCD) for 30 days. Of these groups, 3 groups of rats were treated with either EPA (oral gavage, 35 mg/kg body weight/day), LA (oral gavage, 20 mg/kg body weight/day) or EPA-LA derivative (oral gavage, 50 mg/kg body weight/day) from 16th day to 30th day of the experimental period. RESULTS: HCD induced abnormal increase in lipid peroxidation and serum cholesterol, triglyceride, LDL and VLDL, and a decreased HDL concentration. Altered activity of cardiac and serum creatine kinase, accompanied by a depressed cardiac enzymatic and nonenzymatic antioxidants defense system were observed in HCD fed rats. These changes were partially restored in the EPA and LA treated groups, however, their combined derivative EPA-LA more effectively restored the altered parameters near to that of control (P<0.05). CONCLUSION: Lipid abnormalities and oxidative injury were induced by a hypercholesterolemic diet. Administration of the combination treatment of EPA-LA afforded protection against the lipemic-oxidative injury.  相似文献   
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Maternal and Child Health Journal - Objectives mHealth interventions for MNCH have been shown to improve uptake of antenatal and neonatal services in low- and middle-income countries (LMICs)....  相似文献   
59.
Three novel amino acid based anionic amphiphilic copolymers poly(sodium N-acryloyl-l-valinate-co-alkylacrylamide) (where, alkyl=octyl and dodecyl) with either 9 or 16 mol% hydrophobic substitution were synthesized. These hydrophobically modified polyelectrolytes (HMPs), above a critical concentration, self-assemble in aqueous solution through inter-chain hydrophobic aggregation, forming micelle-like aggregates having hydrodynamic diameter in the range of 50-200 nm. The HMPs were found to undergo conformational changes with the change in solution pH, electrolyte and additive concentration, and temperature. The polymeric micelles were observed to be stable under biological conditions (pH 7.4, [NaCl]=150 mM and temperature (37°C)). The solubilization capacity of the polymeric micelles for six important non-steroidal anti-inflammatory drugs of different hydrophobicity was evaluated. Depending upon the hydrophobicity the solubilities of the drugs were observed to increase ca. 2-10 times in the presence of 1.0 g/L copolymers. The in vitro release kinetics of the loaded drug was studied under physiological pH. To explore their potential application in pharmaceutical industries hemocompatibility and cytotoxicity studies were carried out using hemolytic and MTT assay, respectively. The anionic HMPs were found to be not directly toxic to mammalian cells.  相似文献   
60.
Rheumatoid arthritis is a chronic, progressive and systemic inflammatory disorder mainly affecting the synovial joints. In the present study, we evaluated the anti-arthritic effect of the methanol extract of Saraca asoca (Roxb.) Wilde., (Fabaceae) on adjuvant induced arthritis by assessing paw swelling, body weight, the levels of lysosomal enzymes, protein bound carbohydrates, serum cytokines, urinary collagen and histopathology of joints. It was found that S. asoca methanol extract at doses of 50, 100 and 200 mg/kg reduced the paw thickness and elevated the mean body weight of arthritic rats. The treatment of S. asoca showed a significant reduction in the levels of both plasma and liver lysosomal enzymes. The protein bound carbohydrates and urinary collagen contents were also decreased at a significant level by the treatment of S. asoca methanol extract. The histopathological study of the joints showed the anti-arthritic property of S. asoca which nearly normalized the histological architecture of the joints. Further, we established the anti-arthritic activity of S. asoca methanol extract by measuring the levels of cytokines in both arthritic and treated rats. The treatment of S. asoca reduced the levels of pro-inflammatory cytokines. In conclusion, S. asoca methanol extract was capable of ameliorating the conditions of arthritis in adjuvant induced arthritic rats.  相似文献   
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