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81.
82.
Deterministic dynamic compartmental transmission models (DDCTMs) of human papillomavirus (HPV) transmission have been used in a number of studies to estimate the potential impact of HPV vaccination programs. In most cases, the models were built under the assumption that an individual who cleared HPV infection develops (life-long) natural immunity against re-infection with the same HPV type (this is known as SIR scenario). This assumption was also made by two Australian modelling studies evaluating the impact of the National HPV Vaccination Program to assist in the health-economic assessment of male vaccination. An alternative view denying natural immunity after clearance (SIS scenario) was only presented in one study, although neither scenario has been supported by strong evidence. Some recent findings, however, provide arguments in favour of SIS.  相似文献   
83.
The neonatal brain is vulnerable to oxidative stress, and the pentose phosphate pathway (PPP) may be of particular importance to limit the injury. Furthermore, in the neonatal brain, neurons depend on de novo synthesis of neurotransmitters via pyruvate carboxylase (PC) in astrocytes to increase neurotransmitter pools. In the adult brain, PPP activity increases in response to various injuries while pyruvate carboxylation is reduced after ischemia. However, little is known about the response of these pathways after neonatal hypoxia-ischemia (HI). To this end, 7-day-old rats were subjected to unilateral carotid artery ligation followed by hypoxia. Animals were injected with [1,2-13C]glucose during the recovery phase and extracts of cerebral hemispheres ipsi- and contralateral to the operation were analyzed using 1H- and 13C-NMR (nuclear magnetic resonance) spectroscopy and high-performance liquid chromatography (HPLC). After HI, glucose levels were increased and there was evidence of mitochondrial hypometabolism in both hemispheres. Moreover, metabolism via PPP was reduced bilaterally. Ipsilateral glucose metabolism via PC was reduced, but PC activity was relatively preserved compared with glucose metabolism via pyruvate dehydrogenase. The observed reduction in PPP activity after HI may contribute to the increased susceptibility of the neonatal brain to oxidative stress.  相似文献   
84.
Aims The Framework Convention on Tobacco Control (FCTC) asks countries to develop and disseminate comprehensive evidence‐based guidelines and promote adequate treatment for tobacco dependence, yet to date no summary of the content of existing guidelines exists. This paper describes the national tobacco dependence treatment guidelines of 31 countries. Design, setting, participants A questionnaire on tobacco dependence treatment guidelines was sent by e‐mail to a convenience sample of contacts working in tobacco control in 31 countries in 2007. Completed questionnaires were received from respondents in all 31 countries. During the course of these enquiries we also made contact with people in 14 countries that did not have treatment guidelines and sent them a short questionnaire asking about their plans to produce guidelines. Measurements The survey instrument was a 17‐item questionnaire asking the following key questions: do the guidelines recommend brief interventions, intensive behavioural support, medications; which medications; do the guidelines apply to the whole health‐care system and all professionals; do they refer explicitly to the Cochrane database; are they based on another country's guidelines; are they national or more local; are they endorsed formally by government; did they undergo peer review; who funded them; where were they published; do they include evidence on cost effectiveness of treatment? Findings According to respondents, all their countries' guidelines recommended brief advice, intensive behavioural support and nicotine replacement therapy (NRT); 84% recommended bupropion; 19% recommended varenicline; and 35% recommended telephone quitlines. Nearly half (48%) included cost‐effectiveness evidence. Seventy‐one per cent were supported formally by their government and 65% were supported financially by the government. Most (84%) used the Cochrane reviews as a source of evidence, 84% underwent a peer review process and 55% were based on the guidelines of other countries, most often the United States and England. Conclusion Overall, the guidelines reviewed followed the evidence base closely, recommending brief interventions, intensive behavioural support and NRT, and most recommended bupropion. Varenicline was not on the market in most of the countries in this survey when their guidelines were written, illustrating the need for guidelines to be updated periodically. None recommended interventions not proven to be effective, and some recommended explicitly against specific interventions (for lack of evidence). Most were peer‐reviewed, many through lengthy and rigorous procedures, and most were endorsed or supported formally by their governments. Some countries that did not have guidelines expressed a need for technical support, emphasizing the need for countries to share experience, something the FCTC process is well placed to support.  相似文献   
85.
BackgroundThe US physician workforce does not represent the racial or ethnic diversity of the population it serves.ObjectivesTo assess whether the proportion of US physician trainees of Black race and Hispanic ethnicity has changed over time and then provide a conceptual projection of future trends.DesignCross-sectional, retrospective, analysis based on 11 years of publicly available data paired with recent US census population estimates.ParticipantsA total of 86,303 (2007–2008) to 103,539 (2017–2018) resident physicians in the 20 largest US Accreditation Council for Graduate Medical Education resident specialties.Main MeasuresChanges in proportion of physician trainees of Black race and Hispanic ethnicity per academic year. Projected number of years it will then take, for specialties with positive changes, to reach proportions of Black race and Hispanic ethnicity comparable to that of the US population.Key ResultsAmong the 20 largest specialty training programs, Radiology was the only specialty with a statistically significant increase in the proportion of Black trainees, but it could take Radiology 77 years to reach levels of Black representation comparable to that of the US population. Obstetrics/Gynecology, Emergency Medicine, Internal Medicine/Pediatrics, and Orthopedic Surgery demonstrated a statistically significant increase in the proportion of Hispanic trainees, but it could take these specialties 35, 54, 61, and 93 years respectively to achieve Hispanic representation comparable to that of the US population.ConclusionsAmong US residents in the 20 largest specialties, no specialty represented either the Black or Hispanic populations in proportions comparable to the overall US population. Only a small number of specialties demonstrated statistically significant increases. This conceptual projection suggests that current efforts to promote diversity are insufficient.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-021-06650-7.Key Words: Accreditation Council for Graduate Medical Education, physician workforce, workforce diversity  相似文献   
86.
BackgroundPatients with coronavirus disease 2019 (COVID-19) have a high prevalence of detectable troponin and myocardial injury. In addition, a subset of patients with COVID-19 has detectable severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral loads. The objective of this study was to understand the relationship among SARS-CoV-2 viremia, detectable troponin, and myocardial injury in hospitalized patients with COVID-19.MethodsSARS-CoV-2 plasma viral load was measured in plasma samples drawn from patients hospitalized for COVID-19 at 2 academic medical centers. Baseline characteristics and clinically obtained high-sensitivity cardiac troponin T (hs-cTnT) values were abstracted from the medical record. The main outcome was detectable hs-cTnT (≥6 ng/mL) and myocardial injury (hs-cTnT ≥14 ng/mL; >99th percentile for assay).ResultsA total of 70 hospitalized patients with COVID-19 were included in this study, with 39% females and median age 58 ± 17 years; 21 patients (30%) were found to have detectable SARS-CoV-2 viral load and were classified in the viremia group. Patients with viremia were significantly older than those without viremia. All of the patients with viremia (100%) had detectable troponin during hospitalization compared with 59% of patients without viremia (P = 0.0003). Myocardial injury was seen in 76% of patients with viremia and 38% of those patients without viremia (P = 0.004).ConclusionsHospitalized patients with COVID-19 with SARS-CoV-2 viremia have a significantly higher prevalence of detectable troponin and myocardial injury during their hospitalization compared with patients who did not. This first report of the relationship among SARS-CoV-2 viremia, detectable troponin, and myocardial injury in patients with COVID-19 points to additional mechanistic pathways that require deeper study to understand the complex interplay among these unique findings, cardiovascular outcomes, and mortality in COVID-19.  相似文献   
87.
A t(5;12)(q33;p13) translocation is a recurrent chromosome abnormality in a subgroup of myeloid malignancies with features of both myeloproliferative disorders and myelodysplastic syndromes (MDSs). The molecular consequence of a t(5;12) is a fusion between the platelet- derived growth factor receptor-B gene on chromosome 5 and a novel ETS- like gene, TEL, on chromosome 12. We report on three patients with a t(5;12)(q33;p13) diagnosed as chronic myelomonocytic leukemia, and one case of a t(10;12)(q24;p13) in a progressive MDS, with eosinophilia and monocytosis. Involvement of the TEL gene in these chromosome translocations was investigated by fluorescence in situ hybridization (FISH) with cosmid probes containing selectively the 5' end or 3' end of TEL. Hybridization of these cosmids to the der(5)/der(10) or a der(12), respectively, demonstrated a rearrangement of TEL in both translocations, showing that the t(10;12) is a variant translocation of the t(5;12). Cloning of the fusion cDNA of one case of t(5;12) showed that the breakpoint occurred at the RNA level at exactly the same position as reported by Golub et al (Cell 77:307, 1994). In addition, the TEL gene on chromosome 12 could be localized between two probes previously mapped to 12p13, namely PRB1 and D12S178, leading to a better definition of the position of TEL in this chromosome region. Moreover, in the case involving chromosome 10, the breakpoint occurred between cKTN206 and cKTN312/LYT-10 at 10q24. Clinicohematological data in these studies as well as the restriction mapping of chromosomal breakpoints strongly suggest that (1) common features in MDSs involving the TEL gene are monocytosis and eosinophilia, (2) chromosomes other than no. 5 may be involved and at least a t(10;12)(q24;p13) variant chromosome translocation does exist in these MDSs, and (3) both standard and variant 12p/TEL translocations may be identified by FISH with appropriate probes.  相似文献   
88.
Peripheral T-cell lymphomas consist of a clinically heterogeneous group of malignant disorders whose immunophenotype usually corresponds to that of normal mature T cells. We describe and correlate the clinical, histopathologic, phenotypic, and genotypic findings in two patients with malignant lymphoma presenting with hepatosplenic disease. The morphologic pattern of lymphoma was that of a sinusal/sinusoidal infiltration in spleen, marrow, and liver. This morphologic characteristic was associated with the presence of a productive clonal rearrangement of the T-cell receptor (TCR) delta gene. Lymphoma cells expressed a CD3-TCR-gamma delta- phenotype. They were also double negative (ie, CD4-CD8-) and lacked the CD5 and CD7 antigens. In one patient, tumor progression was associated with phenotypic changes that resulted in a CD3-TCR-gamma delta- phenotype with the same delta-gene rearrangement as initially. These observations suggest the existence of a new type of peripheral T-cell lymphoma characterized by its hepatosplenic presentation, and by the sinusal/sinusoidal tropism and the TCR-gamma delta phenotype of the malignant cells.  相似文献   
89.
Circulating inhibitors against von Willebrand factor (vWF) that show the properties of heterologous IgG antibodies have been described in a few patients with severe von Willebrand disease (vWD). The present study provides further characterization of inhibitors from two patients with severe vWD. Inhibitors in both, like polyclonal rabbit antibody, detected all sizes of multimers and the complex structure of each multimer from platelets and plasma of normal individuals as well as from plasma of patients with IIA, IIB, and IIC vWD. Both inhibitors and the rabbit antibody reacted mainly with the intact 225-Kd vWF subunit and the 189-H and 140-Kd fragments in contrast to monoclonal antibodies specific for vWF fragments that detected a higher relative proportion of 176-Kd fragment. Furthermore, all these antibodies recognized fragment III, although one inhibitor and rabbit polyclonal antibody reacted poorly and the other inhibitor did not react at all with reduced fragment II of vWF digested with Staphylococcus aureus V-8 protease. These data suggest that although human inhibitors from severe vWD patients may behave, to some extent, as polyclonal heterologous antibodies against native vWF, the former show striking differences in their target specificity as well as a much broader specificity than that described for human factor VIII inhibitors.  相似文献   
90.
Venetoclax is a promising agent in the treatment of acute myeloid leukemia (AML), though its antileukemic activity is limited to combination therapies. Mcl-1 downregulation, Bim upregulation, and DNA damage have been identified as potential ways to enhance venetoclax activity. In this study, we combine venetoclax with the dual PI3K and histone deacetylase inhibitor CUDC-907, which can downregulate Mcl-1, upregulate Bim, and induce DNA damage, as well as downregulate c-Myc. We establish that CUDC-907 and venetoclax synergistically induce apoptosis in AML cell lines and primary AML patient samples ex vivo. CUDC-907 downregulates CHK1, Wee1, RRM1, and c-Myc, which were found to play a role in venetoclax-induced apoptosis. Interestingly, we find that venetoclax treatment enhances CUDC-907-induced DNA damage potentially through inhibition of DNA repair. In vivo results show that CUDC-907 enhances venetoclax efficacy in an AML cell line derived xenograft mouse model, supporting the development of CUDC-907 in combination with venetoclax for the treatment of AML.  相似文献   
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