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991.

Background

Historically, humoral immunity was considered unimportant in anti-tumor immunity, and the differentiation and anti-tumor activity of B cells in breast cancer are poorly understood. However, it was recently discovered that B cells participate in tumor immunity through both antibody production and immunosuppressive mechanisms. We analyzed the expression of B-cell differentiation markers in detail using fluorescence-activated cell sorting to investigate the relationship between B-cell subsets and breast cancer etiology.

Methods

Blood samples were taken from breast cancer patients and healthy donors, and peripheral blood mononuclear cells were collected. B cells at various stages of differentiation were identified by the expression of combinations of the cell surface markers CD5, CD19, CD21, CD24, CD27, CD38, CD45, and IgD. Statistical analysis of the proportions of each B-cell subtype in the different patient groups was then performed.

Results

Twenty-seven breast cancer patients and 12 controls were considered. The proportion of total B cells was significantly higher in cancer patients than in controls (11.51 ± 2.059 vs 8.905 ± 0.379%, respectively; p = 0.001). Breast cancer patients were then classified as High-B or Low-B for further analysis. A significantly higher proportion of memory B cells was found in the High-B group than in the Low-B or control groups (p = 0.003 and p = 0.043, respectively).

Conclusions

Breast cancer patients generally have a higher proportion of B cells than healthy controls, but this is highly variable. Analysis of the major B-cell surface markers indicates that memory B cells in particular are significantly expanded, or more robust, in breast cancer patients.
  相似文献   
992.
Describing complex mammography examination processes is important for improving the quality of mammograms. It is often difficult for experienced radiologic technologists to explain the process because their techniques depend on their experience and intuition. In our previous study, we analyzed the process using a new bottom–up hierarchical task analysis and identified key components of the process. Leveraging the results of the previous study, the purpose of this study was to construct a mammographic examination process ontology to formally describe the relationships between the process and image evaluation criteria to improve the quality of mammograms. First, we identified and created root classes: task, plan, and clinical image evaluation (CIE). Second, we described an “is-a” relation referring to the result of the previous study and the structure of the CIE. Third, the procedural steps in the ontology were described using the new properties: “isPerformedBefore,” “isPerformedAfter,” and “isPerformedAfterIfNecessary.” Finally, the relationships between tasks and CIEs were described using the “isAffectedBy” property to represent the influence of the process on image quality. In total, there were 219 classes in the ontology. By introducing new properties related to the process flow, a sophisticated mammography examination process could be visualized. In relationships between tasks and CIEs, it became clear that the tasks affecting the evaluation criteria related to positioning were greater in number than those for image quality. We developed a mammographic examination process ontology that makes knowledge explicit for a comprehensive mammography process. Our research will support education and help promote knowledge sharing about mammography examination expertise.  相似文献   
993.
Adoptive T‐cell therapy is an effective strategy for cancer immunotherapy. However, infused T cells frequently become functionally exhausted, and consequently offer a poor prognosis after transplantation into patients. Adoptive transfer of tumor antigen‐specific stem cell memory T (TSCM) cells is expected to overcome this shortcoming as TSCM cells are close to naïve T cells, but are also highly proliferative, long‐lived, and produce a large number of effector T cells in response to antigen stimulation. We previously reported that activated effector T cells can be converted into TSCM‐like cells (iTSCM) by coculturing with OP9 cells expressing Notch ligand, Delta‐like 1 (OP9‐hDLL1). Here we show the methodological parameters of human CD8+ iTSCM cell generation and their application to adoptive cancer immunotherapy. Regardless of the stimulation by anti‐CD3/CD28 antibodies or by antigen‐presenting cells, human iTSCM cells were more efficiently induced from central memory type T cells than from effector memory T cells. During the induction phase by coculture with OP9‐hDLL1 cells, interleukin (IL)‐7 and IL‐15 (but not IL‐2 or IL‐21) could efficiently generate iTSCM cells. Epstein–Barr virus‐specific iTSCM cells showed much stronger antitumor potentials than conventionally activated T cells in humanized Epstein–Barr virus transformed‐tumor model mice. Thus, adoptive T‐cell therapy with iTSCM offers a promising therapeutic strategy for cancer immunotherapy.  相似文献   
994.
  1. The nonpeptide bradykinin (BK) B2 receptor antagonist, FR165649 (8-[2,6-dichloro-3-[N-[(E)-4-(N- methylcarbamoyl)cinnamidoacetyl] -N-methylamino] benzyloxy] -2 - methylquinoline), and agonist, FR190997 (8-[2,6-dichloro-3-[N-[(E)-4-(N-methylcarbamoyl) cinnamidoacetyl]-N-methylamino]benzyloxy]-2-methyl-4-(2-pyridylmethoxy)quinoline) have been identified. These compounds have a common chemical structure, and the 2-pyridylmethoxy group is the only structural difference between them.
  2. Both FR165649 and FR190997 displaced [3H]-BK binding to B2 receptors in guinea-pig ileum membranes, with an IC50 of 4.7×10−10M and 1.5×10−9M, respectively. They also displaced [3H]-BK binding to B2 receptors in human lung fibroblast IMR-90 cells, with an IC50 of 1.6×10−9M and 9.8×10−10M, respectively.
  3. In guinea-pig isolated ileum-preparations, FR165649 had no agonistic effect on contraction and caused parallel rightward shifts of the concentration-response curves to BK on contraction. Analysis of the data produced a nominal pA2 value of 9.2±0.1 (n=5) and a slope of 1.4±0.1 (n=5). On the other hand, FR190997 induced concentration-dependent contraction of guinea-pig ilea with a pD2 of 7.9±0.2 and the contraction was inhibited by a specific peptide bradykinin B2 receptor antagonist, Hoe 140 (D-Arg-[Hyp3, Thi5, D-Tic7, Oic8]BK) in a non-competitive manner.
  4. In IMR-90 cells, FR165649 had no agonistic effect on phosphatidyl inositol (PI) hydrolysis and caused parallel rightward shifts (approximately 200 fold shift at 10−7M) of the concentration-response curves to BK on PI hydrolysis. FR190997 induced concentration-dependent PI hydrolysis in IMR-90 cells with a pD2 of 8.4±0.1, and this effect was inhibited by Hoe 140.
  5. These results indicate that FR165649 and FR190997 are, respectively, a potent bradykinin B2 receptor antagonist and agonist, and that the agonistic activity depends on the small part of the nonpeptide ligand. FR165649 and FR190997 may be useful tools for studying the relationship between ligands and receptors.
  相似文献   
995.
Livers from 12 mice fed griseofulvin for 4 to 6 months were perfused in situ with a detergent solution to extract lipid membranes leaving the cytoskeleton intact. Seven control mice were similarly studied. After 30 to 120 minutes perfusion, liver samples were examined by scanning electron microscopy and transmission electron microscopy. By light microscopy, Mallory bodies (MBs) were observed in pericentral hepatocytes. These were confirmed by transmission electron microscopy. Intermediate filaments (IFs) were observed in close apposition to MBs. Numerous IFs were seen throughout the cytoplasm. The 3-dimensional organization of the cytoskeleton and MBs were clearly visualized by scanning electron microscopy. The IFs were disorganized in the hepatocytes and formed small MBs in griseofulvin-treated mice. In the case of hepatocytes containing large MBs, there was an apparent decrease in the concentration of IFs. Transition forms of dense networks of IFs between the normal cytoskeleton and the MBs were noted in the cytoplasm between small MBs and the nucleus and also at the cell border. The IFs connected to the nucleus and invaded the MBs. The MBs appeared to form as a result of condensation or collapse of the IFs.  相似文献   
996.
Molecular genetics of methicillin-resistant Staphylococcus aureus   总被引:16,自引:0,他引:16  
A large and growing proportion of Staphylococcus aureus clinical isolates are methicillin resistant, and are resistant to practically all beta-lactam antibiotics. Methicillin-resistant S. aureus (MRSA) strains harbor mecA, which is carried by a unique mobile genetic element, staphylococcal cassette chromosome mec (SCCmec) integrated into the S. aureus chromosome. The mecA gene encodes a methicillin-insensitive transpeptidase, the production of which confers resistance to otherwise inhibitory concentrations of beta-lactam antibiotics. Several distinct clones have been identified among MRSA that apparently have been generated by integration of distinct types of SCCmec. While MRSA are primarily nosocomial pathogens, recent observations indicate that other MRSA clones are colonizing a significant proportion of healthy individuals in the community as well. Community-acquired MRSA (C-MRSA), may become a new threat to humans, and international cooperation of researchers and clinicians will be of cardinal importance in addressing this problem.  相似文献   
997.
The current study explored our hypothesis that IFN-gamma-producing human T cells inhibit human osteoclast formation. Activated T cells derived from human PBMC were divided into IFN-gamma-producing T cells (IFN-gamma(+) T cells) and IFN-gamma-non-producing T cells (IFN-gamma(-) T cells). IFN-gamma(+) T cells were cultured with human monocytes in the presence of macrophage-CSF alone. The concentration of soluble receptor activator of NF-kappaB ligand (RANKL) and IFN-gamma, and the amount of membrane type RANKL expressed on T cells, were measured by ELISA. In the patients with early rheumatoid arthritis (RA) treated with non-steroidal anti-inflammatory drugs alone, CD4+ T cells expressing both IFN-gamma and RANKL were detected by flow cytometry. Surprisingly, IFN-gamma(+) T cells, but not IFN-gamma(-) T cells, induced osteoclastogenesis from monocytes, which was completely inhibited by adding osteoprotegerin and increased by adding anti-IFN-gamma antibodies. The levels of both soluble and membrane type RANKL were elevated in IFN-gamma(+) T cells. The ratio of CD4+ T cells expressing both IFN-gamma and RANKL in total CD4+ T cells from PBMC was elevated in RA patients. Contrary to our hypothesis, IFN-gamma(+) human T cells induced osteoclastogenesis through the expression of RANKL, suggesting that Th1 cells play a direct role in bone resorption in Th1 dominant diseases such as RA.  相似文献   
998.
Endocannabinoids are released from postsynaptic neurons, activate presynaptic cannabinoid receptors and cause various forms of short-term and long-term synaptic plasticity throughout the brain. Using hippocampal and cerebellar neurons, we have revealed that endocannabinoid release can be induced through two different pathways. One is independent of phospholipase Cβ (PLCβ) and driven by Ca2+ elevation alone (Ca2+-driven endocannabinoid release, CaER), and the other is PLCβ-dependent and driven by activation of Gq/11-coupled receptors (receptor-driven endocannabinoid release, RER). CaER is induced by activation of either voltage-gated Ca2+ channels or NMDA receptors. RER is functional even at resting Ca2+ levels (basal RER), but markedly enhanced by a small Ca2+ elevation (Ca2+-assisted RER). In Ca2+-assisted RER, PLCβ serves as a coincidence detector of receptor activation and Ca2+ elevation. We have also demonstrated that Ca2+-assisted RER is essential for the endocannabinoid release triggered by synaptic activity. Our anatomical data show that a set of receptors and enzymes required for RER are well organized so that the excitatory input can trigger RER effectively. Certain forms of spike-timing-dependent plasticity (STDP) are reported to depend on endocannabinoid signalling. The NMDA receptor and PLCβ might play key roles in the endocannabinoid-dependent forms of STDP as coincidence detectors with different timing dependences.  相似文献   
999.
A novel fluorescence probe, 2-[6-(4'-hydroxy) phenoxy-3H-xanthen-3-on-9-yl] benzoic acid (HPF) was used to investigate the generation of highly reactive oxygen species (hROS) under ischemia both in vitro and in vivo. In the in vitro study, HT 22 cells were used to demonstrate that was predominantly detected in the cytoplasm, which coincides with the location of the mitochondria and then its HPF fluorescence gradually increased from 6 to 24 h due to glutamate induced oxidative stress. In the in vivo study, the permanent and transient middle cerebral artery occlusion (MCAO) was induced in rats. Brain slices were incubated in an artificial medium containing HPF. The area of enhanced HPF fluorescence existed in both the ischemic core and the peri-infarct area at 4h after MCAO in both permanent and transient MCAO models. The area extended beyond the boundary of the ischemic damage into biochemically viable tissue. The enhanced fluorescent intensity following transient MCAO was higher than that observed in the permanent MCAO model. Hydroxyl radical scavenger, MCI-186 significantly suppressed the enhanced fluorescence intensity. This study demonstrated that HPF has a high sensitivity and specificity for the detection of hROS in focal cerebral ischemia as well as in a cellular model of oxidative stress.  相似文献   
1000.
The purpose of this study was to examine the retrieval processes in implicit and explicit memory tests by manipulating study tasks and test types. Ninety-six students wrote down target words embedded in the sentences and generated target words using 2-letter cues embedded in the sentences. Students in one test group were asked to recall the target words using the 2-letter cues and then recognize them from the words recalled. Students in the second group were asked to generate words using the 2-letter cues. Students in the third test group were asked to generate words using the 2-letter cues and then recognize the target words from the words generated. The results showed the generation effects in the cued recall test, but in the other test groups, there were no differences between the writing and the generation tasks. The results of the recognition test also showed the interaction between study task and test type. The results suggest that the targets generated are accessed differently between implicit and explicit memory tests.  相似文献   
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