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61.
Several studies have demonstrated that selective serotonin reuptake inhibitor antidepressants can promote neuronal cell proliferation and enhance neuroplasticity both in vitro and in vivo. It is hypothesized that citalopram, a selective serotonin reuptake inhibitor, can promote the neuronal differentiation of adult bone marrow mesenchymal stem cells. Citalopram strongly enhanced neuronal characteristics of the cells derived from bone marrow mesenchymal stem cells. The rate of cell death was decreased in citalopram-treated bone marrow mesenchymal stem cells than in control cells in neurobasal medium. In addition, the cumulative population doubling level of the citalopram-treated cells was signiifcantly increased compared to that of control cells. Also BrdU incorporation was elevated in citalopram-treated cells. These ifndings suggest that citalopram can improve the neuronal-like cell differentiation of bone marrow mesenchymal stem cells by increasing cell proliferation and survival while maintaining their neuronal characteristics.  相似文献   
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B4C-particle-reinforced Al (B4Cp/Al) composites are widely used in various areas, e.g., armors, electronic packaging and fuel storage, owing to their several outstanding properties including high specific rigidity, excellent wear resistance and light weight. Selective laser melting (SLM) is favored in manufacturing complex components because of its high raw material utilization rate and high efficiency. In this work, a B4Cp/Al composite was successfully synthesized by SLM, and the effects of one of the most important parameters, scanning speed (100–700 mm/s), on the phase composition, density, microhardness and tribological properties of the samples were investigated. The microhardness, relative density and dry-sliding wear resistance of as-prepared B4Cp/Al composites were improved with the decrease in scanning speed, and the sample fabricated at a scanning speed of 100 mm/s exhibited a relative density as high as about 97.1%, and a maximum microhardness of ~180 HV0.1 (approximately six times more than that of the SLM-formed pure Al sample, 31 HV0.1), a minimum wear rate of 4.2 × 10−5 mm3·N−1·m−1 and a corresponding friction coefficient of 0.41. In addition, abrasive wear, adhesive wear and oxidation wear were found to be behind the overall wear behavior of as-prepared B4Cp/Al composites.  相似文献   
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BACKGROUND AND PURPOSE: Several prognostic factors have been identified for outcome after stroke. We conducted a study to determine early predictive factors of functional outcome one year after stroke and to evaluate which factors are independent predictors, with an aim of specifying the role of age, aphasia, unilateral neglect, cognitive impairment and family social support. METHODS: Observational cohort study of 156 patients. All patients admitted to the university hospital for initial unilateral hemispheric stroke were included. The study duration was two years (inclusion, one year, and follow-up, one year) .The initial evaluation of stroke was conducted at day 2 and day 15 and included the Motricity Index and Trunk Control Test, New Functional Ambulation Classification, Frenchay arm test, Mini-Mental State Examination, Boston Diagnostic Aphasia Examination, unilateral neglect evaluation, and depression. Data on functional recovery (Barthel Index) were collected at day 360. RESULTS: The average age of patients was 72 years. Age was correlated to social situation (P<0.01) and previous neurological impairment (P<0.01). A multiple regression analysis, including 14 initial clinical factors correlated with the Barthel Index score at day 360, revealed 4 independent early predictive factors of outcome: initial score of Barthel Index at day 2 and its progression from day 2 to day 15, disorders of the executive functions and previous neurological impairment. CONCLUSION: In our cohort, in accordance with previous studies, age, cognitive impairment, unilateral neglect, aphasia, depression and social situation are not independent factors of poor outcome after stroke as evaluated by the Barthel Index.  相似文献   
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During left ventriculography, post-infarction left ventricular aneurysms present as diastolic deformations of the ventricular contour which, when accentuated during systole, give rise to paradoxical systolic expansion. The volumic consequences of thie parietal dyskinesia were studied in 10 cases of chronic anterior wall aneurysm. The borders of the aneurysm were determined by Watson's technique: diastolic and systolic volumes and endocardial surface areas were measured using a computer. In 9 out of 10 cases, neither volume nor endocardial surface area of the aneurysm varied from diastole to systole. Systolic distension of the aneurysm was observed in only one case. In the remainder, paradoxical systolic expansion was related to a charge in the shape of the aneurysm and to overall movement of the heart. The angiographic observations are important for the understanding of the physiopathology of post-infarction aneurysm and for choice of techniques for surgical treatment.  相似文献   
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Transforming growth factor beta‐3 (TGF‐β3) has been shown to decrease scar formation after scheduled topical applications to the cutaneous wounds. This study aimed to continuously deliver TGF‐β3, during the early phase of wound healing, by engineering a dermal equivalent (DE) using TGF‐β3 expressing bone marrow stromal cells (BM‐SCs) and human dehydrated amniotic membrane (hDAM). To engineer a DE, rat BM‐SCs were seeded on the hDAM and TGF‐β3 was transiently transfected into the BM‐SCs using a plasmid vector. Pieces of the dermal equivalent were transplanted onto the full‐thickness excisional skin wounds in rats. The process of wound healing was assessed by image analysis, Manchester Scar Scale (MSS), and histopathological studies 7, 14, 21, and 85 days after the excision. The results confirmed accurate construction of recombinant pcDNA3.1‐TGF‐β3 expression system and showed that the transfected BM‐SCs seeded on hDAM expressed TGF‐β3 mRNA and protein from day 3 through day 7 after transfection. After implantation of the DE, contraction of the wounds was measured from day 7 through 21 and analyzed by linear regression, which revealed that the rate of wound contraction in all experimental groups was similar. Histologic evaluation demonstrated that transfected BM‐SCs decreased retention and recruitment of the cells during the early stage of wound healing, decreased the formation of vascular structures and led to formation of uniformly parallel collagen bundles. MSS scores showed that TGF‐β3 secreting cells significantly improved the cosmetic appearance of the healed skin and decreased the scar formation. From these results, it could be concluded that transient secretion of TGF‐β3, during the early phase of healing, by BM‐SCs seeded on hDAM can improve the cosmetic appearance of the scar in cutaneous wounds without negatively affecting the process of wound repair.  相似文献   
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