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891.

Background

A consensus on the management of Helicobacter pylori has been developed. We aimed to assess whether dissemination through continuing medical education (CME) could enhance the adoption of this consensus among clinicians and to explore potential barriers to acceptance.

Materials and methods

Four CME courses were held to disseminate the consensus. Adoption surveys were performed to evaluate participants’ behavior in the past and their commitment to adopt the consensus in future clinical practice after CME. The gaps and barriers to adoption were also surveyed.

Results

A total of 240 physicians had attended the CME courses and received surveys with the 22 statements/substatements of the consensus. Before CME, adoption was good in six, fair in ten, and poor in six. After CME, 21 statements had either an initial >90% adoption or improvement to good or fair (< 0.001), but one still had poor even though it showed improvement (= 0.02). Although commitment was good or fair after CME, there was a >20% gap between “commitment” and “no barrier” to adoption for 11 statements, ten of which had a main barrier of financial incentives. Among the statements with fair or poor commitment after CME, less commitment to adoption and more barriers related to financial incentives were pronounced in clinicians serving in regional/district hospitals or clinics compared to those serving in medical centers.

Conclusions

Continuing medical education may improve the adoption of the H. pylori consensus. The financial incentives were shown to be a main barrier to adoption of the consensus and should be improved.  相似文献   
892.
893.
Nickel‐rich layered oxide cathodes with the composition LiNi1?x?yCoxMnyO2 (NCM, (1?x?y) ≥ 0.6) are under intense scrutiny recently to contend with commercial LiNi0.8Co0.15Al0.05O2 (NCA) for high‐energy‐density batteries for electric vehicles. However, a comprehensive assessment of their electrochemical durability is currently lacking. Herein, two in‐house cathodes, LiNi0.8Co0.15Al0.05O2 and LiNi0.7Co0.15Mn0.15O2, are investigated in a high‐voltage graphite full cell over 1500 charge‐discharge cycles (≈5–10 year service life in vehicles). Despite a lower nickel content, NCM shows more performance deterioration than NCA. Critical underlying degradation processes, including chemical, structural, and mechanical aspects, are analyzed via an arsenal of characterization techniques. Overall, Mn substitution appears far less effective than Al in suppressing active mass dissolution and irreversible phase transitions of the layered oxide cathodes. The active mass dissolution (and crossover) accelerates capacity decline with sustained parasitic reactions on the graphite anode, while the phase transitions are primarily responsible for cell resistance increase and voltage fade. With Al doping, on the other hand, secondary particle pulverization is the more limiting factor for long‐term cyclability compared to Mn. These results establish a fundamental guideline for designing high‐performing Ni‐rich NCM cathodes as a compelling alternative to NCA and other compositions for electric vehicle applications.  相似文献   
894.
895.
Hyperproliferation of vascular smooth muscle cells (VSMC) is a major risk factor for cardiovascular diseases. Proper mitochondrial fission and fusion is involved with VSMC function. However, the role and mechanism of mitochondrial morphological changes in VSMC proliferation are not well understood. Here, we found that calcium sensing receptor (CaSR) was increased in the aortas from spontaneous hypertensive rats (SHRs) compared with age-matched Wistar Kyoto (WKY) rats. There was also an increase in mitochondrial fission and VSMC proliferation, which was attenuated by Calhex231. In primary rat VMSC, angiotensin II (Ang II) stimulation induced cytosolic [Ca2+]i increase, mitochondrial shortening and proliferation, all of which could be attenuated by pretreatment with mitochondrial division inhibitor-1 (Mdivi-1) and Calhex231. Our data indicate that CaSR-mediated mitochondrial fission could be a therapeutic target for hyperproliferative disorders.  相似文献   
896.
China supports the richest non-human primate diversity in the northern hemisphere, providing an excellent opportunity for Chinese primatologists to take a leading role in advancing the study of primatology.Primatology in China began to flourish after 1979. To date, Chinese primatologists have published more than 1 000 papers in journals indexed by the Chinese Science Citation Database and the Web of Science Core Collection, and universities and academic institutions have trained 107 PhD students and 370 Masters students between 1984 and 2016. In total,the National Science Foundation of China has funded129 primate projects(RMB 71.7 million) supporting 59 researchers from 28 organizations. However, previous research has also shown obvious species bias.Rhinopithecus roxellana, Rhinopithecus bieti, and Macaca mulatta have received much greater research attention than other species. Researchers have also tended to continue to study the same species(55.2%)they studied during their Ph D training. To promote the development of primatology in China, we suggest(1)the need for a comprehensive primatology textbook written in Chinese,(2) continued training of more Ph D students, and(3) encouragement to study less well-known primate species.  相似文献   
897.
Nogo‐B receptor (NgBR) is a type I receptor with a single transmembrane domain and specifically binds to ligand Nogo‐B. A previous study demonstrated that NgBR was highly expressed in human breast invasive ductal carcinoma and promoted epithelial‐mesenchymal transition in breast tumor cells. Our recent work found that NgBR expression was associated with a poor prognosis in human patients with hepatocellular carcinoma (HCC). Here, we elucidate that the increased expression of NgBR contributes toward the increased cell growth of human HCC cells both in vitro and in vivo. Cell viability and clonogenic survival analysis results demonstrated that knockdown of NgBR inhibits the cell growth in human HCC cells, which correlates with a reduction in the phosphorylation of Akt levels. Furthermore, overexpression of NgBR by the cotransfected pIRES‐NgBR plasmid together with NgBR siRNA in human HCC cells can rescue impaired phosphorylation of Akt levels in NgBR knockdown human HCC cells. In addition, cell viability analyses showed that NgBR overexpression can rescue the cell growth inhibition presented in human HCC NgBR knockdown cells. Taken together, our results suggest that NgBR potentially acts as an oncogene in HCC by increasing Akt activity. Thus, NgBR may represent a new potential diagnostic and therapeutic target for the treatment of HCC.  相似文献   
898.
899.
Genetic disruptions of spindle/centrosome-associated WD40-repeat protein 62 (WDR62) are causative for autosomal recessive primary microcephaly (MCPH) and a broader range of cortical malformations. Since the identification of WDR62 as encoded by the MCPH2 locus in 2010, recent studies that have deleted/depleted WDR62 in various animal models of cortical development have highlighted conserved functions in brain growth. Here, we provide a timely review of our current understanding of WDR62 contributions in the self-renewal, expansion and fate specification of neural stem and progenitor cells that are critical for neocortical development. Recent studies have revealed multiple functions for WDR62 in the regulation of spindle organization, mitotic progression and the duplication and biased inheritance of centrosomes during asymmetric divisions. We also discuss recently elaborated WDR62 interaction partners that include Aurora and c-Jun N-terminal kinases as part of complex signalling mechanisms that may define its neural functions. These studies provide new insights into the molecular and cellular processes that are required for brain formation and implicated in the genesis of primary microcephaly.  相似文献   
900.
Neuraminidase (NA) is an important antiviral drug target. Zanamivir is one of the most potent NA inhibitors. In this paper, a series of zanamivir derivatives as potential NA inhibitors were studied by combination of molecular modeling techniques including 3D-QSAR, molecular docking, and molecular dynamics (MD) simulation. The results show that the best CoMFA (comparative molecular field analysis) model has q2?=?0.728 and r2?=?0.988, and the best CoMSIA (comparative molecular similarity indices analysis) model has q2?=?0.750 and r2?=?0.981, respectively. The built 3D-QSAR models show significant statistical quality and excellent predictive ability. Seven new NA inhibitors were designed and predicted. 20?ns of MD simulations were carried out and their binding free energies were calculated. Two designed compounds were selected to be synthesized and biologically evaluated by NA inhibition and virus inhibition assays. One compound (IC50?=?0.670?µM, SI?>?149) exhibits excellent antiviral activity against A/WSN/33 H1N1, which is superior to the reference drug zanamivir (IC50?=?0.873?µM, SI?>?115). The theoretical and experimental results may provide reference for development of new anti-influenza drugs.  相似文献   
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