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61.
Lipopolysaccharide (LPS) administration stimulates immune activation, inflammation and deterioration in cell function. Neuronal tissue in cortex and hippocampus are particularly susceptible. In this study, we report that LPS induces cell death as measured by caspase-3 activation and DNA fragmentation and that this is coupled with stimulation of the mitogen-activated protein kinase, p38. We provide evidence of co-localization of activated p38 and caspase-3 in cells prepared from cortical and hippocampal tissue after LPS treatment. Furthermore, administration of the p38 inhibitor, SB203580, abolished the LPS-induced increase in caspase-3 activation. We observed that LPS treatment provoked accumulation of reactive oxygen species (ROS) while in vitro incubation of cortical and hippocampal tissue with H(2)O(2) increased p38 activity. In addition, H(2)O(2)-induced activation of caspase-3 was abrogated by SB203580. We propose, based on the data presented, that the action of LPS to induce cell death in cortex and hippocampus may be mediated by ROS accumulation and activation of p38.  相似文献   
62.
Intravenous (IV) antibiotics are a mainstay of therapy in children with cystic fibrosis. It is unclear, however, over what period associated improvements in pulmonary function are maintained, and to what extent the underlying inflammatory process is impeded in children admitted for a course of IV antibiotics. This was a prospective, interventional study of 14 children (median age, 14 years; interquartile range, 10-14) with cystic fibrosis who were regular sputum producers and who required admission for a 2-week course of IV antibiotics. Children performed spirometry and provided a sputum sample prior to starting IV antibiotics and then weekly for 6 weeks, the first 2 weeks of which IV antibiotics were given. Sputum IL-8, TNF-alpha, IL-6, IL-10, MIP1-alpha, and elastase were measured. Seven children were asked to repeat the protocol in a subsequent exacerbation to assess similarities in response to therapy. Significant improvements were seen in forced expired volume in 1 sec (FEV(1)) in association with IV antibiotics (27% relative improvement in predicted from baseline to end of week 1, median FEV(1) 41.3% increasing to 52.2%), but this continued only 1 week following cessation of antibiotics. Although IL-8 demonstrated a trend for reduction in association with antibiotics, no significant profile was demonstrated for any of the cytokines assessed. IL-10 was detectable in 64% of samples (all <100 pg/ml). In children with two episodes assessed, although there was a close correlation of FEV(1) and FVC between exacerbations (before antibiotics), no significant correlation was seen for IL-8, TNF-alpha, or IL-10 measured in both sets of samples at any sample point (indeed, a discordant response was seen between sample points in the two exacerbations). Although FEV(1) temporarily improves in response to admission for IV antibiotics, no such response is seen in sputum cytokine values. In addition, assessment of cytokines in subsequent exacerbations does not show a similar pattern of response to treatment.  相似文献   
63.
The present study examined the reliability of a dichotic emotion recognition task under three different conditions presumed to provide different levels of control of attention deployment. Sixty right-handed undergraduate students were randomly assigned to one of the three conditions. The task involved dichotic presentation of words pronounced in an angry, happy, sad, or neutral, emotional tone. The free recall condition applied no attention control. It required participants to report the emotion heard in each ear. Both the monitoring and ABX conditions presumably forced participants to divide their attention equally between the ears. In monitoring, participants were required to indicate when a target emotion was presented to either ear. Finally, the ABX condition required participants to indicate whether the emotional tone of a binaural stimulus matched either of the dichotic stimuli on the same trial. Results showed the expected left ear advantage (LEA). In addition, the monitoring and ABX procedures were found to be somewhat more reliable than the free recall procedure. The present study suggests that control of attention deployment strategies is critical in the reliable assessment of laterality. Issues related to task difficulty and its effect on the reliability and magnitude of laterality effects are also discussed.  相似文献   
64.
Ghosh MK  Li CL  Fayolle C  Dadaglio G  Murphy A  Lemonnier FA  Roy P  Leclerc C 《Vaccine》2002,20(19-20):2463-2473
Epitope-based vaccination strategies designed to induce strong tumor-specific CD8(+) T cell responses are being widely considered for cancer immunotherapy. Here, two recombinant tubular structures, NS1-Mela 1 and NS1-Mela 2, carrying, respectively two HLA-A2 epitopes derived from human melanoma antigens were constructed and their capability to induce CTL responses in vivo were studied in HLA-A2 transgenic mice. Strong CTL responses specific for GnT-V/NA 17-A and gp100 (154-162) epitopes were generated in HLA-A2 transgenic mice immunized by the construct NS1-Mela l carrying these two epitopes. The second construct NS1-Mela 2 carrying both Tyrosinase (369-377Da) and Melan-A/Mart-1 (27-35) epitopes induced a weak Tyrosinase-specific CTL response in mice but failed to induce specific CTL responses against the Melan-A/Mart-1 (27-35) epitope in the tested mice. Thus, recombinant tubular structures containing multiple tumoral epitopes may lead to new strategies for the induction of strong tumor-specific CTL responses in cancer patients.  相似文献   
65.
BACKGROUND: The actions of the extracellular-matrix degrading enzymes, matrix metalloproteinases (MMPs), are implicated in tumorigenesis. The cellular localization of MMP-2, MMP-9, membrane type 1 (MT1)-MMP, tissue inhibitors of metalloproteinases (TIMPs) 1-3, and the presence of active gelatinases were investigated in endometrial carcinoma. METHODS: Endometrial carcinomas were grouped according to histologic grade (Grades 1-3), depth of myometrial invasion (0, < 50%, > 50%) and the presence of vascular/lymphatic invasion. Twenty-nine endometrial carcinoma biopsies were investigated immunohistochemically to determine the tissue localization of MMP-2 (gelatinase A), MMP-9 (gelatinase B), MT1-MMP, and TIMPs 1-3. In situ hybridization was performed to localize MMP-2 and MMP-9 mRNA. The presence of active gelatinases was assessed using in situ zymography. RESULTS: Epithelial tumor cells were the main site of MMP-2, MMP-9, and MT1-MMP protein. Variable stromal cell localization was also observed, particularly in areas adjacent to tumor nests. Semiquantitative analysis revealed increases in MMP-9 and MMP-2 but not MT1-MMP staining scores in tumor epithelial cells in the transition from histologic Grade 1 to Grades 2 and 3. Matrix metalloproteinase-9 and MT1-MMP staining scores in tumor cells were significantly associated with the presence of myometrial invasion and vascular/lymphatic invasion, while MMP-2 did not correlate with these factors. In addition, MT1-MMP was co-localized with MMP-2, supporting its role in the activation of proMMP-2. Tumor cells from all histologic grades stained intensely for TIMP-2 and TIMP-3 proteins, while variable stromal staining was observed. In Grade 1 carcinomas TIMP-1 was predominantly immunolocalized to the stromal compartment with variable tumor cell localization being observed in Grades 2 and 3 carcinomas. Matrix metalloproteinase-9 and MMP-2 mRNAs were predominantly observed in tumor epithelial cells as well as in the stroma to varying degrees. In situ zymography revealed active forms of gelatinases at the cellular surface and in association with tumor epithelial cells within endometrial carcinoma tissues. CONCLUSIONS: These data suggest that increasing expression of MMPs and endometrial carcinoma progression are closely related. Active gelatinases are present in endometrial carcinoma, resulting in alterations to the microenvironment that promote tumor invasion and metastasis.  相似文献   
66.
Colgan TJ  Clarke A  Hakh N  Seidenfeld A 《Cancer》2002,96(4):195-203
BACKGROUND: Cervical carcinoma remains a significant health risk for the older woman. In the current study the yield of screening of mature women in an established, opportunistic screening program was examined. Strategies for improving screening in this age group were identified through examination of recent Pap test history of women with high grade squamous intra-epithelial lesions (HSIL). METHODS: From the population based registry of the Ontario Cervical Screening Program, the Pap test cytodiagnoses for almost 700,000 women screened during the first six months of 2000 were classified by age quintile. Screening yields for younger women (< 50 years of age) and mature women (>/= 50 years of age) were compared using the detection ratio (abnormalities per 1000 women tested). Any pap test results during the three years preceding a diagnosis of HSIL in mature women were identified (excluding any Pap test in the six months immediately prior to the HSIL cytodiagnosis) and classified into one of three categories: no prior test known, prior negative Pap test known, and prior abnormal Pap test known. RESULTS: Twenty four percent of all Pap tests in the six month period were from mature women. Approximately 11% of all cytodiagnoses of HSIL and carcinoma (HSIL+), and 13% of all low grade squamous intra-epithelial lesions (LSIL), HSIL, carcinoma, and atypical glandular cells of uncertain significance (AGUS); [LSIL+ and AGUS] cytodiagnoses, were from mature women. The yield of Pap testing in mature women (1.7 HSIL+ per 1000 women tested) was slightly more than 40% of that for younger women (4.2 HSIL+ per 1000 women tested). Mature women with HSIL were more likely to have had a history of no prior screening (61.1%) than younger women (49.5%). The majority (62.9%) of mature women with HSIL and a prior known Pap test had a prior registered abnormal Pap test. CONCLUSIONS: Pap testing of mature women yields a significant number of abnormalities, but is less efficient than Pap testing of younger women. Screening yield could be increased by recruiting mature women who are currently inadequately screened and by revising guidelines for cessation of screening. Proper followup of mature women with Pap test abnormalities would improve clinical outcome but could adversely affect the yield of Pap testing, since current inappropriate repeat testing of women would decrease.  相似文献   
67.
BACKGROUND: Lung cancer is a frequent cause of death in patients cured of Hodgkin's disease, but the contributions of chemotherapy, radiotherapy, and smoking are not well described. We quantified the risk of treatment-associated lung cancer, taking into account tobacco use. METHODS: Within a population-based cohort of 19 046 Hodgkin's disease patients (diagnosed from 1965 through 1994), a case-control study of lung cancer was conducted. The cumulative amount of cytotoxic drugs, the radiation dose to the specific location in the lung where cancer developed, and tobacco use were compared for 222 patients who developed lung cancer and for 444 matched control patients. All statistical tests were two-sided. RESULTS: Treatment with alkylating agents without radiotherapy was associated with increased lung cancer risk (relative risk [RR] = 4.2; 95% confidence interval [CI] = 2.1 to 8.8), as was radiation dose of 5 Gy or more without alkylating agents (RR = 5.9; 95% CI = 2.7 to 13.5). Risk increased with both increasing number of cycles of alkylating agents and increasing radiation dose (P for trend <.001). Among patients treated with mechlorethamine, vincristine, procarbazine, and prednisone (MOPP), risk increased with cumulative amounts of mechlorethamine and procarbazine (P<.001) when evaluated separately. Statistically significantly elevated risks of lung cancer were apparent within 1-4 years after treatment with alkylating agents, whereas excess risk after radiotherapy began 5 years after treatment and persisted for more than 20 years. Risk after treatment with alkylating agents and radiotherapy together was as expected if individual excess risks were summed. Tobacco use increased lung cancer risk more than 20-fold; risks from smoking appeared to multiply risks from treatment. CONCLUSIONS: Past treatments with alkylating agents and radiation therapy for Hodgkin's disease were associated with an increased risk of lung cancer in a dose-dependent and additive fashion. The precise risk estimates, however, should be interpreted cautiously, given the possible residual and enhancing effects of tobacco.  相似文献   
68.
69.
Objective To evaluate how functional disability impacts on health related quality of life (HRQOL) of patients with extremity soft tissue sarcoma (STS) at 1 year post-surgery.Design and setting Survey of extremity STS patients pre-surgery and one-year post-treatment.Participants: 100 participants who were treated for extremity STS between 2001 and 2003 at four Canadian hospitals. Patients were over 16 years, non-metastatic at diagnosis, and had limb salvage surgery.Outcome measures Musculoskeletal Tumor Society Rating Scale (MSTS), a measure of impairment; Toronto Extremity Salvage Score (TESS), a measure of activity limitations; Reintegration to Normal Living Index (RNL), a measure of participation restrictions; and EQ-VAS, a measure of HRQOL.Results After adjusting for demographic and clinical variables, impairment explained 54%, activity limitations explained 48%, and participation restrictions explained 61% of the variation in HRQOL. After adjustment, when all three functional measures were included in the model, only participation restrictions had a significant impact on HRQOL explaining 63% of the variation.Conclusion Impairment and activity limitations affect the daily activities a patient can perform, but it is the restriction in participation of life roles and situations that has the greatest effect on patient’s HRQOL.  相似文献   
70.
Severe lithium intoxication requires intensive and prolonged hemodialysis as a definitive therapeutic measure. Such an aggressive stand is often needed to prevent the post-dialytic rebound in plasma lithium levels as a result of the drug's relatively slow equilibration across cellular membranes.  相似文献   
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