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Methotrexate (MTX) is broadly used in the treatment of chronic inflammatory diseases such as rheumatoid arthritis (RA). The prevalence of metabolic syndrome (MeS) in patients with this condition is relatively high. Given the importance of adipose tissue in the development of obesity metabolic complications, this study aimed to investigate the effect of methotrexate on preadipocyte proliferation, adipogenesis, and glucose uptake by adipocytes. 3T3-L1 preadipocytes proliferation was evaluated by sulforhodamine B staining and 3H-thymidine incorporation, after 24 or 48 h of treatment with MTX (0.1 and 10 μM). Preadipocytes were induced to differentiate with an appropriate adipogenic cocktail in the presence or absence of MTX. Adipogenesis was determined by measuring lipid accumulation after staining with oil red O. 3H-Deoxyglucose (3H-DG) uptake was determined by liquid scintillation counting. MTX treatment reduced culture protein content in a concentration-dependent manner and 3H-thymidine incorporation (P?<?0.05). MTX (0.1 μM) treatment increased lipid accumulation and basal 3H-DG uptake by adipocytes (P?<?0.05). In 0.1 μM MTX-treated adipocytes, insulin stimulation did not result in an increase of 3H-DG uptake, contrarily to what was observed in control cells. These results demonstrate that methotrexate interferes with adipocyte proliferation and promotes the hypertrophic growth of adipocytes. These molecular effects may have implications on metabolic profile of RA patients treated with MTX.  相似文献   
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Abstract

Background: Unilateral spatial neglect (USN) is the prevalent feature in patients with right-sided stroke. It is diagnosed through the behavior inattention test (BIT) and has a negative impact on patients affecting both their functional capacity and quality of life.

Objective: Here, we aimed to evaluate the impact of USN on the quality of life of patients in the chronic phase of stroke.

Methods: This is a cross-sectional study with stroke patients with USN. After confirming the presence of stroke through neuroimaging examinations and of USN through the BIT, patients’ quality of life was evaluated by using the EUROQOL scale. Spearman’s correlation was used to validate the correlation between patients’ USN and quality of life, with a p?<?.05 representing significant results.

Results: Eighteen individuals were included. When correlating the value of each domain of the EUROQOL scale with the results of the BIT, we observed a negative correlation between mobility (r?=?–0.97; p?=?.000), self-care (r?=?–0.82; p?=?.013), usual activities (r?=?–0.87; p?=?.005); pain or discomfort (r?=?–0.88; p?=?.004), anxiety or depression (r?=?–0.97; p?=?.000), and EUROQOL total score (r?=?–0.97, p?=?.000).

Conclusion: After a correlation between the overall EUROQOL and BIT scores, we suggest that the higher the USN degree is in stroke patients, the worse their perceived quality of life tends to be.  相似文献   
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The Iberian mountain spiny fescues are a reticulate group of five diploid grass taxa consisting of three parental species and two putative hybrids: F. × souliei (F. eskia × F. quadriflora) and F. × picoeuropeana (F. eskia × F. gautieri). Phenotypic and molecular studies were conducted with the aim of determining the taxonomic boundaries and genetic relationships of the five taxa and disentangling the origins of the two hybrids. Statistical analyses of 31 selected phenotypic traits were conducted on individuals from 159 populations and on nine type specimens. Molecular analyses of random amplified polymorphic DNA (RAPD) markers were performed on 29 populations. The phenotypic analyses detected significant differences between the five taxa and demonstrated the overall intermediacy of the F. × picoeuropeana and F. × souliei between their respective parents. The RAPD analysis corroborated the genetic differentiation of F. eskia, F. gautieri and F. quadriflora and the intermediate nature of the two hybrids; however, they also detected genetic variation within F. × picoeuropeana. These results suggest distinct origins for F. × picoeuropeana in the Cantabrian and Pyrenean mountains, with the sporadic Pyrenean populations having potentially resulted from recent hybridizations and the stabilized Cantabrian ones from older events followed by potential displacements of the parents. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173 , 676–706.  相似文献   
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We evaluated the use of a newly described sodC-based real-time-polymerase chain reaction (RT-PCR) assay for detecting Neisseria meningitidis in normally sterile sites, such as cerebrospinal fluid and serum. The sodC-based RT-PCR assay has an advantage over ctrA for detecting nongroupable N. meningitidis isolates, which are commonly present in asymptomatic pharyngeal carriage. However, in our study, sodC-based RT-PCR was 7.5% less sensitive than ctrA. Given the public health impact of possible false-negative results due to the use of the sodC target gene alone, sodC-based RT-PCR for the diagnosis of meningococcal meningitis should be used with caution.  相似文献   
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The major goal of this work was to design a new nanoparticle drug delivery system for desoxycholate amphotericin B (D-AMB), based on controlled particle size, looking for the most successful release of the active agents in order to achieve the best site-specific action of the drug at the therapeutically optimal rate and dose regimen. For this, AMB nanoencapsulated in poly(lactic-co-glycolic acid) (PLGA) and dimercaptosuccinic acid (DMSA) nanoparticles (Nano-D-AMB) has been developed, and its efficacy was evaluated in the treatment of experimental cutaneous leishmaniasis in C57BL/6 mice, to test if our nano-drug delivery system could favor the reduction of the dose frequency required to achieve the same therapeutic level of free D-AMB, and so, an extended dosing interval. Magnetic citrate-coated maghemite nanoparticles were added to this nanosystem (Nano-D-AMB-MG) aiming to increase controlled release of AMB by magnetohyperthermia. Female mice (N = 6/group) were infected intradermally in the right footpad with promastigotes of Leishmania amazonensis in the metacyclic phase, receiving the following intraperitoneal treatments: 1% PBS for 10 consecutive days; D-AMB at 2 mg/kg/day for 10 days (totalizing 20 mg/kg/animal); Nano-D-AMB and Nano-D-AMB-MG at 6 mg/kg on the 1st, 4th and 7th days and at 2 mg/kg on the 10th day, also totalizing 20 mg/kg/animal by treatment end. The Nano-D-AMB-MG group was submitted to an AC magnetic field, allowing the induction of magnetohyperthermia. The evaluations were through paw diameter measurements; parasite number and cell viability were investigated by limiting dilution assay. D-AMB-coated PLGA–DMSA nanoparticles showed the same efficacy as free D-AMB to reduce paw diameter; however, the Nano-D-AMB treatment also promoted a significantly greater reduction in parasite number and cell viability compared with free D-AMB. The nano-drug AMB delivery system appeared more effective than free D-AMB therapy to reduce the dose frequency required to achieve the same therapeutic level. It thus favors a longer interval between doses, as expected with development of a new nano drug delivery system, and may be useful in the treatment of many different pathologies, from cancer to neurodegenerative diseases.  相似文献   
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Nine O-alkyl and O-prenyl derivatives were synthesized from commercial 2,4-dihydroxybenzophenone, 4,e4,4′-dihydroxybenzophenone and were evaluated for their leishmanicidal activity against promastigote forms of Leishmania amazonensis, as well their toxicity in murine macrophages. All derivatives exhibited better biological activity than their hydroxylated benzophenones precursors, and new compound LFQM-123 (3c) was 250-fold more active than its precursor 4,4′-dihydroxybenzophenone (3). Moreover, some of the results were comparable to the standard drug Amphotericin B, suggesting that the increase in lipophilicity could facilitate protozoa membrane permeation. In this study we confirmed that benzophenone derivatives exhibit leishmanicidal properties, with relatively low toxicity, and thus could be exploited as promise prototypes for the design and development of new drug for the treatment of leishmaniasis.  相似文献   
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