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71.
Cell adhesion is an essential biological function for division, migration, signaling and tissue development. While it has been demonstrated that this cell function can be modified by using nanometer-scale surface topographic structures, it remains unknown how contaminants such as indium (III) ion might influence this specific cell behavior. Herein, the influence of indium chloride on human dermal fibroblast (GM5565) adhesion characteristics was investigated, given the frequent contact of contaminants with skin. The morphology of the adherent cells and their mitochondrial reticulum was characterized on cell culture dishes and nanopatterned surfaces by using fluorescence confocal microscopy and scanning electron microscopy. Results showed a significant proportion of cells lost their ability to align preferentially along the line axes of the nanopattern upon exposure to 3.2 mM indium chloride, with cells aligned within 10° of the pattern line axes reduced by as much as ~70%. Concurrent with the cell adhesion behaviors, the mitochondria in cells exposed to indium chloride exhibit a punctate staining that contrasts with the normal network of elongated tubular geometry seen in control cells. Our results demonstrate that exposure to indium chloride has detrimental effects on the behavior of human fibroblasts and adversely impacts their mitochondrial morphology. This shows the importance of evaluating the biological impacts of indium compounds.  相似文献   
72.
Long considered merely a trophic and mechanical support to neurons, astrocytes have progressively taken the center stage as their ability to react to acute and chronic neurodegenerative situations became increasingly clear. Reactive astrogliosis starts when trigger molecules produced at the injury site drive astrocytes to leave their quiescent state and become activated. Distinctive morphological and biochemical features characterize this process (cell hypertrophy, upregulation of intermediate filaments, and increased cell proliferation). Moreover, reactive astrocytes migrate towards the injured area to constitute the glial scar, and release factors mediating the tissue inflammatory response and remodeling after lesion. A novel view of astrogliosis derives from the finding that subsets of reactive astrocytes can recapitulate stem cell/progenitor features after damage, fostering the concept of astroglia as a promising target for reparative therapies. But which biochemical/signaling pathways modulate astrogliosis with respect to both the time after injury and the type of damage? Are reactive astrocytes overall beneficial or detrimental for neuroprotection and tissue regeneration? This debate has been animating this research field for several years now, and an integrated view on the results obtained and the possible future perspectives is needed. With this Commentary article we have attempted to answer the above-mentioned questions by reviewing the current knowledge on the molecular mechanisms controlling and sustaining the reaction of astroglia to injury and its stem cell-like properties. Moreover, the cellular/molecular mechanisms supporting the detrimental or beneficial features of astrogliosis have been scrutinized to gain insights on possible pharmacological approaches to enhance astrocyte neuroprotective activities.  相似文献   
73.
Our previous works have indicated that extracellular ATP is an important prometastasis factor. However, the molecular mechanism involved needs to be further studied. We demonstrated that extracellular ATP treatment could upregulate the expression of connective tissue growth factor (CTGF) in both triple‐negative breast cancer (TNBC) cells and endothelial cells (ECs). Extracellular ATP stimulated the migration of TNBC cells and ECs, and angiogenesis of ECs via the P2Y2––YAP‐CTGF axis. Furthermore, we demonstrated that adenosine triphosphate (ATP) stimulated TNBC cell adhesion to ECs and transmigration through the EC layer via CTGF by upregulation of integrin β1 on TNBC cells and VCAM‐1 on ECs. Both apyrase (ATP‐diphosphohydrolase) and CTGF shRNA treatments could inhibit the metastasis of inoculated tumors to lung and liver in a mouse model, and these treated tumors had fewer blood vessels. Collectively, our data indicated that extracellular ATP promotes tumor angiogenesis and the interactions between TNBC cells and ECs through upregulation of CTGF, thereby stimulating TNBC metastasis. The pleiotropic effects of ATP in angiogenesis and cell adhesion suggest that extracellular ATP or CTGF could be an effective target for TNBC therapy.  相似文献   
74.
补骨脂对体外黑素细胞黏附和迁移的作用   总被引:4,自引:0,他引:4  
目的 :研究补骨脂对黑素细胞黏附和迁移的影响。方法 :用补骨脂处理黑素细胞 ,检测其黏附于牛血清纤维结合素和通过微孔滤膜的细胞数量并与生姜和未经药物处理的黑素细胞比较。结果 :补骨脂可显著促进黑素细胞黏附于牛血清纤维结合素和通过微孔滤膜并呈剂量依赖关系 ,但当补骨脂浓度超过 0.2mg·L-1时这种作用未见增加。补骨脂浓度在 0.01mg·L-1时 ,黑素细胞黏附并无显著增加 ,但对迁移的影响已可见统计学差异 (P <0.01)。生姜则不具有这样的作用。结论 :在体外 ,补骨脂能明显促进黑素细胞的黏附和迁移 ,这至少可以部分解释应用补骨脂治疗白癜风是有效的。  相似文献   
75.
Asherman syndrome--one century later   总被引:1,自引:0,他引:1  
  相似文献   
76.
77.
In the present study, attempts have been made to determine the effects of honey on intestinal morphology, postoperative adhesions, and the healing of colonic anastomoses in the rats after colonic resection and anastomosis. Thirty-six rats were randomly divided into three groups each including 12 animals. Colonic resection and anastomosis were performed on all animals. Rats were fed with standard rat chow in group I, standard rat chow plus 10 g/kg/day honey in group II and artificial honey including the same caloric amount with honey in group III. Adhesion scores, bursting pressures and histopathological examinations were evaluated. Colonic bursting pressures of honey group were significantly better than control and artificial honey groups. Histological analysis of anastomotic site showed that submucosa and muscularis propria were nearly filled with granulation tissue and regular fibrin matrix in honey group. There was statistically significant difference between the adhesion scores of honey vs artificial honey and control groups. The scores of histological changes of ileum in honey group were significantly different from other groups. These results indicate a protective role of honey against intraabdominal adhesions and anastomotic dehiscence.  相似文献   
78.
目的观察雷公藤多甙对糖尿病肾病患者的尿蛋白和血清可溶性细胞间粘附因子-1(sICAM-1)表达的影响。方法将60例糖尿病肾病患者分为两组,对照组(30例)给以依那普利口服,治疗组(30例)给以雷公藤多甙口服。疗程为1个月,观察治疗前后尿蛋白定量和血清sICAM-1等指标的变化。结果对照组与治疗组尿蛋白定量均较治疗前下降,两组间比较无差异性;治疗组血清sICAM-1治疗后较治疗前降低,而对照组治疗前、后无明显变化。结论雷公藤多甙可以减少糖尿病肾病患者的尿蛋白,其机制可能与降低血清sICAM-1的表达有关。  相似文献   
79.
Acutelunginjury(Al.I)whichoccursasacomplicationofacutehemorrhagicnecroticpancreatitis(AHNP)becomesahotprobleminhepatobiliarysurgery.Previousstudiesindicatedthattheaccumulationofpolymorphonuclearneutrophils(PMNs)inthelungsplaysakeyroleinthedamagesofpulmonaryparenchymalcellsandinterstitialedemainAHNPLlj.However,themechanismofPMNaccumulationinthelungsisnotclearlyknown.ThisstudywascarriedoutonaratmodelofAHNPcomplicatedwithAl-I,TheauthorsintendedtoclarifytherelationshipofPMNaccumulationi…  相似文献   
80.
This study proposes a novel use of laser heating to increase the adhesion between coatings fabricated by low-temperature PVD and replaceable cemented carbide cutting inserts, thus extending the life of these cutting tools in the machining of difficult-to-machine materials. Our previous studies conducted on CVD coatings showed that these coatings had higher adhesion due to a much higher process temperature. However, taking into account the fact that PVD coatings have better technological properties (e.g., lower structure porosity, higher hardness, and better tribological properties) than CVD coatings, it is fully justified to investigate ways of improving the PVD coating adhesion to the substrate. In this study, replaceable cutting inserts with different hard coatings of titanium nitride were used. Laser heating was conducted with different power densities. The adhesion strength of the tested coatings was determined via vibration spectrum analysis. In addition, 2D surface imaging, scanning electron microscopy, and X-ray fluorescence spectrometry were employed to examine the coatings after laser heating. A significant increase in the adhesion of single-layer (TiN) and double-layer (TiCN + TiN) coatings to the cemented carbide substrate, together with increased tool life, was observed after heating the samples with 40% of the maximum laser power. The application of a multilayer coating containing thermal shock-sensitive (TiAlSi) N did not increase the tool life. This paper attempts to interpret the obtained results.  相似文献   
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