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71.
Swathi Kiran 《Aphasiology》2013,27(2):231-261
Background: Edmonds and Kiran (2006 Edmonds, L. and Kiran, S. 2006. Effect of semantic based treatment on cross linguistic generalisation in bilingual aphasia.. Journal of Speech, Language and Hearing Research, 49: 729748. [Crossref], [PubMed], [Web of Science ®] [Google Scholar]) reported that training lexical retrieval in one language resulted in within‐language and cross‐language generalisation in three bilingual (English–Spanish) patients with aphasia.

Aims: The present experiment continues this line of research, repeating a similar procedure with new patients and examining a broader range of factors that may affect generalisation patterns.

Methods & Procedures: Four participants (two Spanish–English and two French–English speakers) with anomia post CVA received a semantic feature‐based treatment aimed at improving naming of English or Spanish/French nouns. Using a multiple baseline design, generalisation to untrained semantically related and unrelated items in each language was measured during periods of therapy first in one language, then in the other.

Outcomes & Results: All patients improved their naming of the trained items in the trained language, although to varying degrees. Within‐language generalisation to semantically related items occurred in two Spanish–English patients and one French–English patient. Cross‐language generalisation to translations and semantically related items occurred only for one French–English patient.

Conclusions: The impact of the intervention is very clear. The semantic feature‐based practice is linked to the gains made, and accounts for the predominance of semantic naming errors after treatment. Possible explanations for the different patterns of generalisation are considered in terms of the various factors including each patient's pre‐stroke language proficiency, age of acquisition of each language, post‐stroke level of language impairment, and type and severity of aphasia.  相似文献   
72.
73.
NiMoS2 nanoparticles supported on carbon, synthesized by a microemulsion method were used as a nanocatalyst for hydrodeoxygenation (HDO) of a lignin model compound – guaiacol. Two types of carbon supports – mesoporous carbon (CMK-3) and activated carbon (AC) with a predominantly microporous structure, were studied to investigate the role of porosity and nature of the porous structure in catalyst activity. The activity of NiMoS2/AC resulted in the complete guaiacol conversion at 13 h of reaction time to produce phenol (31.5 mol%) and cyclohexane (35.7 mol%) as the two main products. Contrastingly, NiMoS2/CMK-3 needed a much lesser reaction time (6 h) to attain a similar conversion of guaiacol but gave different selectivities of phenol (25 mol%) and cyclohexane (55.5 mol%). Increased cyclohexane production with NiMoS2/CMK-3 implied better deoxygenation of MoS2 and enhanced hydrogenation capacity of Ni since phenol is a partially deoxygenated product of guaiacol while cyclohexane is a completely deoxygenated and hydrogenated product. The superior catalytic activity and deoxygenating behavior of NiMoS2/CMK-3 catalysts could be attributed to the organized mesoporosity of the CMK-3 support in relation to the improved active phase distribution and access to active sites that facilitate the conversion of the reaction''s product. Recyclability study implied NiMoS2/CMK-3 was more stable without significant changes in the catalytic activity even after three reaction cycles.

NiMoS2 nanoparticles supported on carbon, synthesized by a microemulsion method were used as a nanocatalyst for hydrodeoxygenation (HDO) of a lignin model compound – guaiacol.  相似文献   
74.
Reduced mobilization of endothelial progenitor cells (EPCs) from the bone marrow (BM) and impaired EPC recruitment into the wound represent a fundamental deficiency in the chronic ulcers. However, mechanistic understanding of the role of BM‐derived EPCs in cutaneous wound neovascularization and healing remains incomplete, which impedes development of EPC‐based wound healing therapies. The objective of this study was to determine the role of EPCs in wound neovascularization and healing both under normal conditions and using single deficiency (EPC) or double‐deficiency (EPC + diabetes) models of wound healing. MMP9 knockout (MMP9 KO) mouse model was utilized, where impaired EPC mobilization can be rescued by stem cell factor (SCF). The hypotheses were: (1) MMP9 KO mice exhibit impaired wound neovascularization and healing, which are further exacerbated with diabetes; (2) these impairments can be rescued by SCF administration. Full‐thickness excisional wounds with silicone splints to minimize contraction were created on MMP9 KO mice with/without streptozotocin‐induced diabetes in the presence or absence of tail‐vein injected SCF. Wound morphology, vascularization, inflammation, and EPC mobilization and recruitment were quantified at day 7 postwounding. Results demonstrate no difference in wound closure and granulation tissue area between any groups. MMP9 deficiency significantly impairs wound neovascularization, increases inflammation, decreases collagen deposition, and decreases peripheral blood EPC (pb‐EPC) counts when compared with wild‐type (WT). Diabetes further increases inflammation, but does not cause further impairment in vascularization, as compared with MMP9 KO group. SCF improves neovascularization and increases EPCs to WT levels (both nondiabetic and diabetic MMP9 KO groups), while exacerbating inflammation in all groups. SCF rescues EPC‐deficiency and impaired wound neovascularization in both diabetic and nondiabetic MMP9 KO mice. Overall, the results demonstrate that BM‐derived EPCs play a significant role during wound neovascularization and that the SCF‐based therapy with controlled inflammation could be a viable approach to enhance healing in chronic diabetic wounds.  相似文献   
75.
The impact of pepsin on the maintenance of supersaturated solution of the HCl salt of a weakly basic drug was evaluated in simulated gastric fluid by monitoring the drug solubility in the absence and presence of pepsin. In the presence of pepsin, the HCl salt maintained its apparent solubility through 24?h, whereas, no such solubility advantage was seen in the absence of pepsin. Consequently, a minimum inhibitory concentration of pepsin is required for maintenance of supersaturation. In addition, NMR study seems to indicate a molecular level interaction between pepsin and HCl salt leading to a weak binding between the two. Therefore, for the HCl salts of weak bases having disproportionation potential, it is preferred that preformulation solubility studies are conducted in the presence of pepsin to reflect their in vivo behavior in maintaining supersaturation solubility.  相似文献   
76.
Type I IFNs are used for treating viral, neoplastic, and inflammatory disorders. The protein products encoded by IFN-stimulated genes (ISGs) likely mediate clinical effects of IFN in patients. Macroarray assays, used for studying ISG induction in IFN-treated patients, comprise genes identified predominantly through analysis of long-term cell lines. To discover genes induced selectively by IFN-beta in PBMC, we exposed whole blood to physiological concentrations of IFN-beta. PBMC were prepared, and RNA was extracted, reverse-transcribed, and hybridized to cDNA microarrays, and microarray analysis identified 39 ISGs and 20 IFN-repressed genes (IRGs). Thirty-three ISGs were known previously, and six ISGs were novel. New ISGs included GTP cyclohydrolase 1; hypothetical protein LOC129607; hypothetical protein FLJ38348; leucine aminopeptidase 3; squalene epoxidase; and GTP-binding protein overexpressed in skeletal muscle. Twenty IRGs included IL-1beta and CXCL8, which had been identified earlier. CXCL1 was a novel IRG identified in the current study. PCR analysis demonstrated the regulation of six novel ISGs and CXCL1 as an IRG in PBMC and astrocytoma cells. Results were validated using RNA obtained ex vivo from blood of patients after injection with IFN-beta. Identification of new ISGs and IRGs in primary PBMC will enhance macroarray assays for monitoring IFN responsiveness.  相似文献   
77.
78.

Objectives

To identify steps per day in a large sample of persons with multiple sclerosis (MS) and to describe variation by demographic and clinical characteristics and device type.

Design

Cross-sectional design.

Setting

General community.

Participants

Convenience sample of persons with multiple sclerosis (N=645) recruited from the general community who were ambulatory and relapse free for 30 days. Mean age ± SD of the participants was 46.3±10.6 years old. Participants were mostly women (85%), white (93%), and employed (64%).

Interventions

Not applicable.

Main Outcome Measure

Step counts measured by a motion sensor during a 7-day period.

Results

The average value for the entire sample was 5903±3185 steps per day. This value varied by demographic and clinical characteristics, but not device type, and indicated that men, participants who were unemployed, had a high school education or less, progressive MS, a longer disease duration, and higher disability were less physically active based on the metric of steps per day.

Conclusions

This study provides an expected value for average steps per day among persons with MS. Such an expected value for this population is an important first step to help researchers and clinicians interested in improving the overall health of persons with MS through physical activity promotion.  相似文献   
79.
Advances in animal models of retinoblastoma have accelerated research in this field, aiding in understanding tumor progression and assessing therapeutic modalities. The distinct pattern of mutations and specific location of this unique intraocular tumor have paved the way for two types of models- those based on genetic mutations, and xenograft models. Retinoblastoma gene knockouts with an additional loss of p107, p130, p53 and using promoters of Nestin, Chx10, and Pax6 genes show histological phenotypic changes close to the human form of retinoblastoma. Conditional knockout in specific layers of the developing retina has thrown light on the origin of this tumor. The use of xenograft models has overcome the obstacle of time delay in the presentation of symptoms, which remains a crucial drawback of genetic models. With the advances in molecular and imaging technologies, the current research aims to develop models that mimic all the features of retinoblastoma inclusive of its initiation, progression and metastasis. The combination of genetic and xenograft models in retinoblastoma research has and will help to pave way for better understanding of retinoblastoma tumor biology and also in designing and testing effective diagnostic and treatment modalities.  相似文献   
80.
Vitamin E D-alpha-tocopheryl polyethylene glycol succinate (TPGS) and polyethylene glycol are common excipients used in both preclinical and commercial formulations. In this paper, the phase diagrams of TPGS and polyethylene glycol 400 (PEG 400) in the presence of either water or ethanol were constructed. The effect of water and ethanol on the cloud point temperature of TPGS-PEG 400 mixtures was investigated. In general, the cloud point temperature was reduced by the presence of either water or ethanol in the formulation. However, water was more effective in lowering the cloud point temperature than ethanol. Similarly, the phase diagram of TPGS-PEG 1450 was constructed. The cloud point temperature was observed to decrease with increasing TPGS concentration. It was found that TPGS and PEG 1450 could form a single phase when TPGS concentration was above 75%, based on differential scanning calorimetry, and FT-Raman analysis indicated that a vibration at 1330 cm(-1) disappeared in the melted single phase. In addition, a systematic melting point depression was observed for the mixtures of TPGS-PEG 1450. In the presence of Ibuprofen, a model compound, the cloud point temperature was also reduced. Finally, the extended Flory-Huggins theory for polymer solution was used to analyze the entropic and enthalpic contributions of water and ethanol to the free energy of mixing.  相似文献   
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