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目的:观察蛙皮素(BBS)对前列腺癌PC-3细胞骨架形态及细胞内游离Ca2+([Ca2+]i)浓度的影响。方法:①利用免疫荧光法(IH),结合激光扫描共聚焦显微镜(LSCM)检测10-5mol/L浓度BBS处理的PC-3细胞角蛋白(CK)的表达,以反映其对细胞骨架形态的影响;②应用Fluo-3/AM荧光标记技术和LSCM检测不同浓度BBS(10-9、10-7、10-5mol/L)处理的PC-3细胞[Ca2+]i浓度。结果:①10-5mol/L浓度的BBS可促进PC-3细胞CK表达及伪足形成;②BBS可提高PC-3细胞[Ca2+]i浓度,并具有浓度依赖性。结论:实验证明一定浓度的BBS可明显提高PC-3细胞[Ca2+]i浓度及CK表达,进而影响PC-3细胞骨架形态。本研究为探索BBS应用于肿瘤研究以及BBS作用后细胞内信息传递途径提供了基础。  相似文献   
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BACKGROUND: Vitiligo is the most common pigmentary disorder with a global incidence from 0.1% to 2% in different geographical areas. Histopathology and histochemistry have shown the reduction of melanocytes in achromic patches, but microscopic changes of lesional and non-lesional skin are still not completely understood. Reflectance confocal microscopy (RCM), based on the different light reflectance index of cutaneous structures, allowed in vivo, en face microscopic evaluation of superficial skin layers with a resolution similar to skin histology. AIM: The purpose of this study was to evaluate RCM features of lesional and non-lesional skin of vitiligo patients. Moreover, re-pigmented areas were taken into consideration in order to evaluate melanocyte response to ultraviolet B (UVB) radiation. SUBJECTS AND METHODS: Sixteen patients of different phototypes affected by active non-segmental vitiligo and 10 controls were enrolled in the study. In vivo skin imaging was done using a commercially available RCM (Lucid, Vivascope 1500. Re-pigmented areas from 6 to 16 patients (after UVB narrow-band therapy) were also examined. RESULTS: Vitiligo lesions showed the disappearance of the bright rings normally seen at the dermo-epidermal junction. Moreover, non-lesional skin of vitiligo patients showed unexpected changes as the presence of half-rings or scalloped border-like features of the bright papillary rings. In re-pigmented areas after UVB narrow band therapy, the presence of activated, dendritic melanocytes was seen. CONCLUSIONS: Considering our results, and following further studies, RCM clinical applications could be used in the therapeutic monitoring and evaluation of the evolution of vitiligo.  相似文献   
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整合素β1在自身免疫性心肌炎小鼠心肌的表达   总被引:2,自引:1,他引:1       下载免费PDF全文
目的:观察整合素β1在自身免疫性心肌炎小鼠心肌的表达变化。方法:猪肌凝蛋白皮下注射免疫Balb/c小鼠,建立慢性自身免疫性心肌炎模型,于初次免疫后14、30和60d对心肌组织进行病理学检查,同时用激光共聚焦技术和间接免疫荧光法检测整合素β1在心肌的表达变化。结果:在初次免疫后14d,小鼠心脏有局部炎症出现,整合素β1在心脏血管周围的表达高于正常组(P<0.05);在第30天,小鼠心脏炎性浸润更加明显,整合素β1在心肌的表达增强,显著高于正常组(P<0.05);第60天,小鼠心脏炎症细胞减少,而纤维化则开始出现,整合素β1在心肌的表达最强(P<0.05),且排列紊乱。结论:整合素β1在自身免疫性心肌炎的发生及发展过程中起着不同重要作用,整合素β可能参与自身免疫反应及心肌的重构。  相似文献   
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The phagocytic activity of human first trimester extravillous trophoblast   总被引:20,自引:3,他引:17  
It has been suggested previously that phagocytic activity inthe human placenta is confined to cells of the macrophage lineage.However, earlier studies were hampered by the paucity and poorviability of cells inherent in primary trophoblast cell cultures,contamination by other cell types which themselves have phagocyticactivity, lack of reliable markers of trophoblasts, and by limitationsof methods available to demonstrate unequivocally the internalizationof particulate material. We have overcome these limitationsby using: (i) DNA transfection to provide unlimited suppliesof pure trophoblast cell lines; (ii) human placental lactogenas a marker unique to trophoblast; and (iii) confocal microscopyof demonstrate unequivocally the intracellular locality of phagocytosedmaterial. We found that both untransfected primary culture extravilloustrophoblast cells, as well as the cell lines, had the capacityto phagocytose sheep red blood cells, Staphylococcus aureusand baker's yeast cells, and that this activity was inhibitedby cytochalasin B and by culture at 4°C. Phagocytic activityin trophoblast cells was less avid than that seen in a professionalphagocyte. In physiological and pathological situations wheretissue remodelling occurs, such as the rapid turnover in theperiodontal ligament or during inflammation, epithelial cellsand other cells that are not considered professional phagocytesactively phagocytose components of the extracellular matrix.We postulate that phagocytosis by human trophoblasts may playan important role in the extensive tissue remodelling that occursduring trophoblastic invasion of the decidua.  相似文献   
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BACKGROUND: Eosinophil cationic protein (ECP) is an eosinophil-derived protein, which has been shown to be present in circulating neutrophils. OBJECTIVE: To establish whether ECP is produced or internalized by peripheral blood neutrophils. METHODS: This was done using microscopy, flow cytometry, fractionation of cells and RT-PCR techniques. RESULTS: No ECP mRNA was detected after extensive cell purification to eliminate all traces of contaminating eosinophils. Examination of immunostained neutrophils by light, confocal, electron microscopy together with cell fraction experiments, established that ECP is present intracellularly and is mostly associated to cell granules. Uptake studies by flow cytometry and by using both cold and radiolabelled ECP showed that it is internalized by neutrophils and stored in some proportion in their primary granules. Upon stimulation with serum-treated Sephadex particles, the internalized ECP was partially released from cells. CONCLUSION: ECP is not produced but can be internalized by circulating neutrophils, which take it from the environment and partially store it in their primary granules.  相似文献   
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The development of locomotor function in the rat spans the first 3 postnatal weeks. We have studied morphological features of the soma and dendrites of motoneurons innervating the physiological flexor muscles of the ankle, tibialis anterior and extensor digitorum longus, by intracellular injection in vitro between the first and ninth postnatal days. We obtained serial optical sections of 96 adequately filled motoneurons in whole-mounted hemisected spinal cords by confocal microscopy, projected them onto a single plane and analysed them morphometrically. On the day after birth, the somatodendritic surfaces of most such motoneurons were covered in growth-associated spiny, thorny or hair-like appendages. These had disappeared from the soma by the fourth postnatal day and from most proximal dendrites by day 7, but were still common distally on day 9. During this period there was little or no net growth of either the soma (which was still much smaller than in the adult) or the dendritic tree. A dorsal dendritic bias was present and 'sprays' of long, loosely bundled dorsal dendrites were often seen. The mean number of primary dendrites remained constant at about eight, and their combined diameter was already significantly correlated with mean soma diameter, as in the adult cat. Thus, the critical neonatal period during which these ankle flexor motoneurons are known to change their electrophysiological properties and to be particularly sensitive to interference with neuromuscular interaction is characterized by major changes in the neuronal surface, presumably linked to synaptogenesis.  相似文献   
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The aim of this study was to evaluate corneal innervation in soft contact lens wearers using the Tomey Confoscan confocal microscope (40x/0.75 objective lens). Three distinct age- and sex-matched subject groups were involved, including extended soft (hydrogel and silicone-hydrogel) contact lens wearers, overnight soft (hydrogel) contact lens wearers, and non contact lens wearers. A number of variables were objectively measured, subjectively evaluated, or graded in order to investigate the distribution and morphology of corneal nerves. For most of the evaluated parameters, no statistically significant differences were found. However, qualitative observations showed noticeable differences in corneal nerve appearance among the different subject groups; the degree of corneal oedema was suggested as the main causative factor. In conclusion, neither the short-term (overnight wear) nor the long-term (12-month extended wear) soft contact lens wear appeared to affect the morphology and/or distribution of corneal nerves as viewed with confocal microscopy.  相似文献   
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