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91.
目的探讨水通道蛋白(AQP)5基因对异位子宫内膜腺上皮细胞增殖及迁移的影响。方法构建可靶向沉默AQP5基因的质粒, 在293T细胞中包装形成病毒颗粒后, 感染原代培养的异位子宫内膜腺上皮细胞, 分别通过逆转录PCR及蛋白质印迹法鉴定异位子宫内膜腺上皮细胞中AQP5 mRNA和蛋白表达。MTT法测定细胞增殖; Transwell技术检测细胞的体外迁移能力; 蛋白质印迹法检测丝氨酸/苏氨酸蛋白酶(AKT)活化情况。构建裸鼠腹腔内子宫内膜异位症体内模型, 考察阴性对照组和AQP5沉默组子宫内膜腺上皮细胞在裸鼠腹腔内瘤体生长情况及腹膜转移情况。结果体外实验结果显示, AQP5沉默后异位子宫内膜腺上皮细胞的增殖能力在第7天时明显抑制( P < 0.05);AQP5沉默组异位子宫内膜腺上皮细胞磷酸化(p-AKT)表达减少, 而AKT表达无改变, p-AKT/AKT减少( P < 0.05);AQP5沉默组比阴性对照组迁移细胞数减少( P < 0.05)。体内实验结果显示, 与阴性对照组比较, AQP5沉默组瘤体结节数相对较少, 体积较小, 其中腹膜瘤体结节数少于阴性对照组( P < 0.05)。 结论AQP5基因沉默可抑制异位子宫内膜腺上皮细胞的增殖及迁移能力, 其机制可能与AKT活化有关。  相似文献   
92.
《Vaccine》2015,33(35):4269-4280
Adaptation of continuous cell lines to growth in suspension in a chemically defined medium has significant advantages for design and optimization in manufacturing of biologicals. In this work, changes in the protein expression level during a step-wise adaptation of an adherent Madin Darby canine kidney (MDCK) cell line to suspension growth were analyzed. Therefore, three cell line adaptations were performed independently. Two adaptations were monitored closely to characterize short term changes in protein expression levels after serum deprivation. In addition, initial stages of suspension growth were analyzed for both adaptations. The third adaptation involved MDCK suspension cells (MDCKSUS2) grown over an extended time period to achieve robust growth characteristics. Here, cells of the final stage of adaptation were compared with their parental cell line (MDCKADH). A combination of two dimensional differential gel electrophoresis for relative protein quantification and tandem mass spectrometry for protein identification enabled insights into cellular physiology. The two closely monitored cell line adaptations followed different routes regarding specific changes in protein expression but resulted in similar proteome profiles at the initial stages of suspension growth analyzed. Compared to the MDCKADH cells more than 90% of all changes in the protein expression level were identified after serum deprivation and were related to cytoskeletal structure, genetic information processing and cellular metabolism. Myosin proteins, involved in cellular detachment by actin-myosin contractile mechanisms were also differentially expressed. Interestingly, for both of the two adaptations, proteins linked for tumorigenicity, like lactoylglutathione lyase and sulfotransferase 1A1 were differentially expressed. In contrast, none of these proteins were differentially expressed for the MDCKSUS2 cell line. Overall, proteomic monitoring allowed identification of key proteins involved in adaptation from adherent to suspension growth. In addition, identified proteins related to tumorigenicity may represent markers to support cell clone selection at early stages of industrial cell line development.  相似文献   
93.
94.
The chemical composition, structure and surface characteristics of biomaterials/scaffold can affect the adsorption of proteins, and this in turn influences the subsequent cellular response and tissue regeneration. With magnesium/calcium phosphate cements (MCPC) as model, the effects of magnesium (Mg) on the initial adhesion and osteogenic differentiation of bone marrow stromal cells (BMSCs) as well as the underlying mechanism were investigated. A series of MCPCs with different magnesium phosphate cement (MPC) content (0∼20%) in calcium phosphate cement (CPC) were synthesized. MCPCs with moderate proportion of MPC (5% and 10%, referred to as 5MCPC and 10MCPC) were found to effectively modulate the orientation of the adsorbed fibronectin (Fn) to exhibit enhanced receptor binding affinity, and to up-regulate integrin α5β1 expression of BMSCs, especially for 5MCPC. As a result, the attachment, morphology, focal adhesion formation, actin filaments assembly and osteogenic differentiation of BMSCs on 5MCPC were strongly enhanced. Further in vivo experiments confirmed that 5MCPC induced promoted osteogenesis in comparison to ot her CPC/MCPCs. Our results also suggested that the Mg on the underlying substrates but not the dissolved Mg ions was the main contributor to the above positive effects. Based on these results, it can be inferred that the specific interaction of Fn and integrin α5β1 had predominant effect on the MCPC-induced enhanced cellular response of BMSCs. These results provide a new strategy to regulate BMSCs adhesion and osteogenic differentiation by adjusting the Mg/Ca content and distribution in CPC, guiding the development of osteoinductive scaffolds for bone tissue regeneration.  相似文献   
95.
Breast cancer mortality is principally due to recurrent tumors that arise from a reservoir of residual tumor cells that survive therapy. Remarkably, breast cancers can recur after extended periods of clinical remission, implying that at least some residual tumor cells pass through a dormant phase prior to relapse. Nevertheless, the mechanisms that contribute to breast cancer recurrence are poorly understood. Using a mouse model of recurrent mammary tumorigenesis in combination with bioinformatics analyses of breast cancer patients, we have identified a role for Notch signaling in mammary tumor dormancy and recurrence. Specifically, we found that Notch signaling is acutely upregulated in tumor cells following HER2/neu pathway inhibition, that Notch signaling remains activated in a subset of dormant residual tumor cells that persist following HER2/neu downregulation, that activation of Notch signaling accelerates tumor recurrence, and that inhibition of Notch signaling by either genetic or pharmacological approaches impairs recurrence in mice. Consistent with these findings, meta-analysis of microarray data from over 4,000 breast cancer patients revealed that elevated Notch pathway activity is independently associated with an increased rate of recurrence. Together, these results implicate Notch signaling in tumor recurrence from dormant residual tumor cells and provide evidence that dormancy is a targetable stage of breast cancer progression.  相似文献   
96.
Several inflammatory markers have been investigated as prognostic parameters in a variety of cancer population with mostly favorable results. This study aimed to verify the significance of common inflammatory markers as prognostic variables and assess whether a selective combination of them as prognostic inflammation score (PIS) could further improve their prognostic values in surgical patients with colorectal cancer (CRC). A total of 265 patients who had undergone curative resection of CRC were reviewed retrospectively. Preoperative levels of inflammatory markers such as serum C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), white blood cell count (WBC), and neutrophil/lymphocyte ratio (NLR) were assessed by uni- and multivariate survival analysis with disease-free (DFS) and disease-specific survival (DSS). PIS was constructed with a selective combination of inflammatory markers which were independently significant. On univariate analysis, CRP, ESR, and NLR were significantly associated with DFS and DSS. On multivariate analysis, CRP and NLR were independently significant prognostic variables for DSS and DFS respectively (P=0.013, P=0.021). When PIS was constructed with combination of CRP and NLR, it was independently and significantly associated with both DFS and DSS (P=0.006, P=0.010). Furthermore, PIS was superior to CRP for DSS (HR=15.679 vs. HR=5.183), and NLR for DFS in terms of prognosticating power (HR=4.894 vs. HR=2.687). When PIS is constructed with combination of CRP and NLR, it is a potentially significant prognostic variable associated with poor survival regardless pathologic prognostic variables in patients with CRC after curative resection.  相似文献   
97.
98.
ObjectiveSickle Cell Disease (SCD) is an inherited blood disorder that includes acute pain episodes and chronic pain that can dramatically impact quality of life and goal-achievement. Our staff had limited success in connecting families with the Pain, Palliative Care and Integrative Medicine Clinic (PPCIM) to receive specialized skills for pain management. We created a partnership between Hematology and PPCIM to provide SCD patients/families with needed resources.Design/settingIn 2016, key stakeholders collaborated to create a Sickle Cell Wellness Clinic (SCWC) clinic to provide families access to integrative medicine and wellness strategies. Design/structure, based on family focus group data and staff expertise, included a half-day, 7-discipline clinic housed in the PPCIM space. Patients with SCD, ages 8–20, learned strategies in an effort to improve health care utilization and increase overall quality of life.Main outcome measures/resultsFeedback from two successful pilot clinics in 2017 was incorporated into the formal roll-out of SCWC in 2018. SCWCs continued monthly for one year, serving a total of 20 families post-pilot. SCD patients increased follow-up appointment engagement in the PPCIM clinic following SCWC and reported high levels of satisfaction with their healthcare experience.ConclusionsIt is feasible to run a multidisciplinary clinic focused on pain management, coping skills, and healthy living with SCD. Providers benefited from the opportunity to collaborate with other disciplines. Patient and family feedback was positive, highlighted benefits of being introduced to new modalities, and reported advantages of meeting other patients/families in a new setting.  相似文献   
99.
The aim of this study was to investigate antibacterial activity of Origanum compactum essential oils collected at three phenological stages on Escherichia coli and Bacillus subtilis. The antibacterial activity was evaluated using the agar-well diffusion assay. The MIC and MBC values were determined using the micro-dilution assay. The investigation of the antibacterial action was carried out by the evaluation of the effect of O. compactum essential oils on the antibacterial kinetic growth, the integrity of cell membrane and permeability of the cell membrane. The anti-quorum sensing activity was tested by the inhibition of the biofilm formation. The findings of this study showed that O. compactum essential oil has potent antibacterial activities against E. coli and B. subtilis. The lowest inhibition value against B. subtilis was obtained with O. compactum essential oil at the post-flowering stage (MIC = MBC = 0.0312% (v/v)). The antibacterial mechanisms of O. compactum essential oils are related to the disturbing of the cell membrane integrity and the increasing of the membrane permeability, which leads to the leakage of genetic materials (DNA and RNA). Moreover, O. compactum essential oils inhibited the formation of the biofilms, a phenotype that has been known to be quorum sensing regulated.  相似文献   
100.
Objectives: It is noteworthy that several animal species are known to withstand high levels of radiation, and are exposed to heavy metals but rarely been reported to develop cancer. For example, the scorpion has been used as folk medicine in ancient civilizations of Iran and China, while amphibian skin is known to possess medicinal properties. Here, we elucidated the anti-tumour activity of the scorpion (Uropygi) and frog (Lithobates catesbeianus). Materials and Methods: Animals were procured and their organ lysates and sera were prepared and tested against Michigan Cancer Foundation-7 breast cancer (MCF-7), prostate cancer (PC3), Henrietta Lacks cervical cancer (HeLa), and normal human keratinocyte cells. Exoskeleton, appendages and hepatopancreas were dissected from the scorpion, whereas liver, lungs, heart, oviduct, gastrointestinal tract, gall bladder, kidneys, eggs and sera were collected from frog and organ lysates/sera were prepared. Growth inhibition assays and cytotoxicity assays were performed. Results: Appendages, exoskeleton lysates, and hepatopancreas from scorpion exhibited potent growth inhibition, and cytotoxic effects. Furthermore, lungs, liver, gastrointestinal tract, heart, oviduct, kidneys, eggs, and sera from frog displayed growth inhibition and cytotoxic effects. Conclusion: Organ lysates, sera of scorpion, and amphibians possess anti-tumour activities. This is a worthy area of research as the molecular identity of the active molecule(s) together with their mechanism of action will lead to the rational development of novel anticancer agent(s).  相似文献   
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