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31.
The purpose of this study was comparison of VEGF (vascular endothelial growth factor) levels in serum and pleural fluid and estimation of this test usefulness in diagnosis of pleural effusions. VEGF levels were measured by ELISA method in 68 patients (45 males and 23 females) aged 19-81 years. By Light's criteria in 16 cases transudate and in 52 cases exudate was recognized. By means of fluid cytology, pleural biopsy, microbiology or thoracoscopy in 10 cases pleural metastases from distant organs, in 15 cases coexisting pulmonary neoplasm, in 11 cases mesothelioma and in 16 cases tuberculosis were determined as a cause of fluid accumulation in pleural space. The mean VEGF levels were significantly higher (p < 0.001) in patients with exudates than in patients with transudates (3833 pg/ml and 325 pg/ml respectively). Based on likelihood ratios analysis, as a cut off value in differentiation of exudates and transudates a value 700 pg/ml was accepted. The sensitivity of this test was 75% and the specificity 93% and likelihood ratio (LR) 12.5. The mean VEGF level in exudates was seven times higher than mean VEGF level in serum (3833 pg/ml and 573 pg/ml respectively). Mean VEGF levels in malignant exudates (4615 pg/ml) were significantly higher than in tuberculous exudates (2073 pg/ml). As a cut off value in differentiation between malignant and tuberculous exudates a value of 4500 pg/ml was accepted. We conclude that our results suggests the local VEGF production in pleural cavity and the significant role of this cytokine in pleural exudates accumulations and also suggests the usefulness of VEGF estimation in pleural fluid in differentiation transudates from exudates and malignant from tuberculous pleural fluids.  相似文献   
32.
Human mitochondrial diseases are usually caused by dysfunction of mitochondrial DNA (mtDNA), particularly by point mutations, deletions, or depletions. In commonly used procedures for molecular diagnostics of mitochondrial dysfunction, one of the first steps is linearization of circular mitochondrial genomes with either BamHI or PvuII restriction endonulease, which cuts human mtDNA at a unique site. Here, we describe a case of false positive results, which suggested mtDNA depletion or a large deletion in a patient's tissue sample. More detailed analysis (mtDNA sequencing) revealed that these false positive results were caused by the presence of the 12753A>G substitution in the gene coding for NADH dehydrogenase subunit 5 (ND5). This substitution results in no change in amino acid sequence of the gene product but creates an additional PvuII site. Investigating a population of 200 patients not affected by mitochondrial diseases, we found an additional case of 12753A>G, and also another substitution, 12804T>C, which also results in no change in amino acid sequence of ND5 but creates an additional PvuII site. A few cases of 12753A>G and 12804T>C substitutions were found previously in Asian, American, African, and European populations (though they were not reported to date in the MITOMAP), but those samples were used in population studies and not tested for mtDNA deletion or depletion. Therefore, we present a cautionary report indicating that these mtDNA polymorphisms exist in various human populations (and thus, they are panethnic) and may cause false positive results of standard molecular analyses, including molecular diagnostics, of human mtDNA.  相似文献   
33.
A system composed of a functional continuous magnetic stimulator (FCMS) and a saddle-type coil has been developed for non-invasive treatment of urinary incontinence, especially stress incontinence and urge incontinence. The FCMS conditions were as follows: 2 kW maximum electrical power consumption, 800 V maximum capacitor voltage, 720 μs pulsewidth (180 μs rise time), and 5–30 Hz frequency. A frequency between 5 and 10 Hz is used to treat urge incontinence and a frequency between 25 Hz and 30 Hz is used to treat urge incontinence. The coil (120 mm long, 90 mm wide and 50 mm thick) fits the most suitable region for this treatment, the region from the anus to the perineum. The coil is cooled to maintain a coil temperature between 20 and 25°C so that it can be used efficiently and safely. In experiments with anaesthetised dogs, it was confirmed that the urethral pressure increased when the circumference of the perineum received continuous magnetic stimulation of 720 μs pulsewidth (180 μs rise time), 10Hz frequency and about 520 V capacitor voltage. This result suggests that magnetic stimulation can be effective as a urinary incontinence therapy.  相似文献   
34.
Three patients with Alzheimer's disease, a 68-year-old woman with mild dementia and 2 men (aged 64 and 72 years) with moderate dementia were treated orally with the cholinesterase inhibitor tacrine (tetrahydroaminoacridine), 80 mg daily, for several months. The patients were investigated using positron emission tomography (PET) prior to, and after 3 weeks and 3 months of treatment. The PET studies involved a multi-tracer system consisting of [18F]-fluoro-deoxy-glucose (18F-FDG) (tracer for glucose metabolism); 11C-butanol (cerebral blood flow) and (S)(−)- and (R)(+)-[N-11C-methyl]-nicotine (nicotinic receptors; cholinergic neural activity). Tacrine treatment increased the uptake of 11C-nicotine to the brain. Significant reduced difference in uptake between the two enantiomers (S)(−)- and (R)(+)11C-nicotine was observed in the frontal and temporal cortices after tacrine treatment in all three patients. The kinetic analysis indicated increased binding of (S)(−)11C-nicotine in brain compatible with a restoration of nicotinic cholinergic receptors. The most pronounced effect was observed after 3 weeks and 3 months treatment in the patient with mild dementia. An increase in cerebral glucose utilization was found in the 68-year-old patient with mild dementia but also slightly in the 64-year-old man with moderate dementia when treated with tacrine for 3 months. Tacrine administration did not affect cerebral blood flow. The PET data obtained after 3 weeks of tacrine treatment was paralleled by improvement in neuropsychological performance. This study shows in vivo by PET neurochemical effects induced in brain by treatment with tacrine to Alzheimer patients. Intervention with tacrine in the early course of the disease might be necessary for clinical improvement.  相似文献   
35.
INTRODUCTION: During acute inflammation, leukocyte infiltration is mostly neutrophilic, but later monocytes prevail. The majority of inflammatory cells, particularly neutrophilic polymorphonuclear leukocytes (PMNs), become apoptotic at later stages of inflammation and are phagocytosed by neighboring cells, mostly by macrophages. Recently, it has been found that human peripheral blood monocytes also recognize apoptotic cells, which primes them to increased production of interleukin (IL)-10--a cytokine known to reduce phagocytes' ability to engulf and kill pathogens. Based on the above, we studied monocytes' ability to phagocytose and kill Staphylococcus aureus while in contact with apoptotic cells. MATERIALS AND METHODS: Monocytes isolated by elutriation were co-cultured with apoptotic PMNs or Jurkat cells and exposed to viable, human serum-opsonized S. aureus. To induce apoptosis PMNs were cultured overnight while Jurkat cells were UV-treated. Apoptosis, phagocytosis of bacteria and intracellular superoxide production were measured by flow cytometry. Production of reactive oxygen species was also followed by measurement of chemiluminescence. The bactericidal effect was determined by standard colony forming units method. RESULTS: Data presented show that contact of monocytes with apoptotic neutrophils and Jurkat cells had no influence on monocyte phagocytosis of S. aureus, the generation of reactive oxygen species, or the killing of bacteria. CONCLUSION: The data obtained suggest that monocytes attracted to the inflammatory site are not deficient in their ability to cope with pathogens after contact with apoptotic cells despite increased production of IL-10.  相似文献   
36.
The ageing process is accompanied by the disregulation of interleukin 2 (IL2) and interleukin 6 (IL6) production. In our paper, we asked whether the age between 60 and 70 years is a turning point for the disregulation of both IL2 and IL6 production. Fifty volunteers 60–70 years old, 25 aged 36–59, and 50 of 20–35 years old were enrolled into the study. Their health status was graded according to the criteria of the Senieur Protocol (SP) as ‘healthy' and ‘almost-healthy'. The cytokines level was determined in the sera of the volunteers. Moreover, the spontaneous release of IL6 by peripheral blood mononuclear cells (PBMC) and the activity of the IL6 gene in non-stimulated PBMC were also analysed. Cytokine levels were measured by biological assays, mRNA for IL6 was detected by RT-PCR method. The results showed that the production of IL2 is not disregulated in the ‘healthy' people until the age of 60–70. People not fulfilling all SP criteria are characterised by a lower level of IL2 in the sera. The overproduction of IL6 into the sera and supernatants from non-stimulated PBMC and PBL as well as the activation of IL6 gene start between the ages 36 and 59 and is more pronounced in the ‘almost-healthy'.  相似文献   
37.
The cognitive behaviour therapy (CBT) emphasis on treatment relevance in assessment, and on evidence‐based intervention, has led to an increasing focus on problem maintenance factors (vs. precipitants) in both its models of psychopathology and in its individual case formulations. This article describes the reasons for this growing focus, and presents a generic CBT model based on the functional analysis of “problem‐maintaining circles” (PMCs) of causes. Some samples of the profuse literature implicating PMCs in many psychological disorders are presented, and the utility of PMC‐based functional analysis, case formulation, or modelling of psychopathology is advanced, not only as a guide to selection of therapeutic interventions, but as an alternative to standard psychiatric diagnosis. A sampling of a taxonomy of such PMCs is presented. And finally, the clinical application of PMC‐based functional analysis, case formulation, and treatment selection is illustrated in five case illustrations drawn from a recent clinical caseload.  相似文献   
38.
Although the thymus is the source of all mature peripheral T lymphocytes, the majority of thymocytes die intrathymically. Until recently, there has been no phenotypic marker to allow definition of the generative thymocyte lineage, thereby distinguishing those thymocytes committed to death from those which will evenually give rise to thymic emigrants. We believe that expression of the high-molecular-mass isoforms (p190, p205, and/or p220) of the leukocyte common antigen (CD45) distinguishes the thymic generative lineage from the vast majority of thymocytes expressing the low-molecular-mass isoform (p180) of CD45 and committed to die within the thymus. The thymocytes defined by their lack of CD45 p180, the low-molecular-mass isoform, comprise all thymocytes with clonogenic potential and include all major subsets defined by CD4 and CD8. We have proposed that a CD45 p180 lineage exists in the human thymus and that this lineage results in the production of mature thymocytes and thymic emigrants. The objective of the present study was to determine by DNA analysis whether the degree of cell cycling in subsets of human thymus, defined by selective expression of high-molecular-mass isoforms of CD45, was sufficient to account for the generation of thymic emigrants. Multicolor immunofluorescence analysis of surface markers and 7-amino actinomycin D as well as propidium iodide staing was used to measure the DNA content of thymic subsets. Negative depletion methods were used to isolate and characterize human thymocyte subsets defined by CD45 isoform, CD3, CD4, and CD8, and subsequently to determine the cell cycle status of the isolated subsets by flow-cytometric analysis of cellular DNA content. CD3−/lo thymocytes had a high number and CD1−/lo thymocytes a low number of cycling cells, consistent with murine data. CD45 p 180 cells, as well as the CD48 and CD348 subsets which express high molecular-weight CD45 isoforms, exhibited a significant number of cycling cells. Since CD45 p180- thymocytes exhibited a significant number of cycling cells, based on numerical arguments we conclude that this cycling thymocyte fraction is capable of generating the daily requirements of mature thymocytes and thymic emigrants.  相似文献   
39.

Background

Peanut allergy has a rising prevalence in high-income countries, affecting 0.5%–1.4% of children. This study aimed to better understand peanut anaphylaxis in comparison to anaphylaxis to other food triggers in European children and adolescents.

Methods

Data was sourced from the European Anaphylaxis Registry via an online questionnaire, after in-depth review of food-induced anaphylaxis cases in a tertiary paediatric allergy centre.

Results

3514 cases of food anaphylaxis were reported between July 2007 - March 2018, 56% in patients younger than 18 years. Peanut anaphylaxis was recorded in 459 children and adolescents (85% of all peanut anaphylaxis cases). Previous reactions (42% vs. 38%; p = .001), asthma comorbidity (47% vs. 35%; p < .001), relevant cofactors (29% vs. 22%; p = .004) and biphasic reactions (10% vs. 4%; p = .001) were more commonly reported in peanut anaphylaxis. Most cases were labelled as severe anaphylaxis (Ring&Messmer grade III 65% vs. 56% and grade IV 1.1% vs. 0.9%; p = .001). Self-administration of intramuscular adrenaline was low (17% vs. 15%), professional adrenaline administration was higher in non-peanut food anaphylaxis (34% vs. 26%; p = .003). Hospitalization was higher for peanut anaphylaxis (67% vs. 54%; p = .004).

Conclusions

The European Anaphylaxis Registry data confirmed peanut as one of the major causes of severe, potentially life-threatening allergic reactions in European children, with some characteristic features e.g., presence of asthma comorbidity and increased rate of biphasic reactions. Usage of intramuscular adrenaline as first-line treatment is low and needs to be improved. The Registry, designed as the largest database on anaphylaxis, allows continuous assessment of this condition.
  相似文献   
40.
Investigations into the changes that occur in microvasculature following the surgical procedure called delay have brought about the need for a computer system capable of quantifying the morphological features of a full microvascular network in terms of average vessel length, diameter, and tortuosity. Both the formulaic conventions that have been developed to measure these quantities as well as their implementation in the form of a HP-9000/UNIX based computer software system that we developed specifically for this purpose are discussed. Reliability studies performed using the final system to measure the microcirculatory network of a mouse latissmus dorsi muscle (LDM) showed 95% confidence intervals within 5% of means and coefficients of variability within 7% of means for all quantities measured in large (150–300 μm), medium (50–150 μm), and small (<50 μm) diameter vessels. These variations were significantly smaller than the changes that were observed in a preliminary study comparing these microvascular network parameters before and after delay in the hairless mouse LDM, showing the proposed quantification methods to be well suited to the study of the microvascular changes following delay. It is hoped that the formulaic conventions, implementation process and reliability data will provide a useful comparison for other researchers interested in measuring similar features of microcirculatory networks.  相似文献   
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