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11.
Ziora D Sielska-Spytek E Dworniczak S Oklek K Kozielski J 《Pneumonologia i alergologia polska》2002,70(9-10):458-467
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
12.
Anna Weglewska-Jurkiewicz Joanna Jakóbkiewicz-Banecka Ewa Pronicka Grzegorz Wegrzyn 《Diagnostic molecular pathology》2007,16(2):116-120
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
13.
Agneta Nordberg Anders Lilja Hans Lundqvist Per Hartvig Kaarina Amberla Matti Viitanen Ulrika Warpman Monika Johansson Ewa Hellstrm-Lindahl Peter Bjurling Karl-Johan Fasth Bengt Lngstrm Bengt Winblad 《Neurobiology of aging》1992,13(6):747-758
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
14.
Jolanta My?liwska Ewa Bryl Jerzy Foerster Andrzej My?liwski 《Mechanisms of ageing and development》1998,100(3):718-328
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
15.
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 CD4−8− and CD3−4−8− 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
16.
Witold Kuran Stanisaw Pasynkiewicz Zbigniew Florjanczyk Ewa Lusztyk 《Macromolecular chemistry and physics.》1976,177(9):2627-2635
Complexes of acrylonitrile and of methyl methacrylate with various Lewis acids, 1 and 2 , were studied by means of IR, NMR, and UV spectroscopy. The influence of the Lewis acid strength on the induction effect and on the delocalization of π-electrons in the complexed monomer molecule was established. As the relative acidity of the complexing agent is increased, the inductive effect of the nitrile or of the carbonyl group in the complex molecule rises, whereby the electron density on the carbon atom in β-position in the vinyl group diminishes. Complexation of the monomer also results in increased delocalization of π-electrons in the molecule. In the complexes with moderately strong Lewis acids like CH3AlCl2 and C2H5AlCl2, delocalization of π-electrons seems to reach its maximum. The methyl methacrylate-C2H5AlCl2 complex was found to give a charge-transfer complex with 1,5-cyclooctadiene. On the basis of the present spectroscopic studies and of earlier studies on copolymerization of acryl monomers with butadiene, the delocalization of π-electrons in the complexed monomer molecule is believed to be one of the major factors controlling the rate of copolymerization. 相似文献
17.
Katarzyna Pawowska-Gral Ewa Kusz Maria Wardas Ewa Adamek Piotr Wardas 《Experimental and toxicologic pathology》2002,54(2):147-150
We examined 72 female Wistar rats which were divided into 6 groups. The animals were administered sodium nitrate (V), vitamin E or both compounds at the same time. In order to estimate the interference of nitrates in the presence of vitamin E with the metabolism of rat's liver, we determined the composition and the amount of glycosoaminoglycans (GAGs). It was stated that the total amount of GAGs increased in livers of all rats. Basing on all fractions of the examined GAGs it was determined that the most significant differences between individual groups appeared in the amount of heparane sulphate (HS). The results obtained confirmed the fact of the changes taking place in the picture of liver GAGs in the process of ageing of the examined animals. The results obtained, however, allowed to state the normalising influence of vitamin E on the quantitative composition of GAGs of rats which drank nitrates. 相似文献
18.
Frequent polymorphism of the mitochondrial DNA polymerase gamma gene (POLG) in patients with normal spermiograms and unexplained subfertility 总被引:4,自引:0,他引:4
Jensen M Leffers H Petersen JH Nyboe Andersen A Jørgensen N Carlsen E Jensen TK Skakkebaek NE Rajpert-De Meyts E 《Human reproduction (Oxford, England)》2004,19(1):65-70
BACKGROUND: Male fertility largely depends on the quality of sperm production, which may be affected by environmental and genetic factors. In this study, we explored a possible role of the polymerase gamma (POLG) gene polymorphism, recently reported to be associated with male infertility in some populations. METHODS: The polymorphic CAG repeat (usually 10 codons long) in the POLG gene was studied in 1298 male subjects: 429 patients with infertility/subfertility, and 869 controls (495 men from the general population with unknown fertility and 374 recent fathers). In all subjects, the POLG polymorphism was assessed in relation to their semen quality, and--in the fertile controls--with biological fecundity measured as waiting time-to-pregnancy (TTP) for the couples. In the patients lacking the common POLG allele, the outcome of the assisted reproductive techniques (ART) for the couples was evaluated. RESULTS: The absence of one (10/ not equal to 10) or both common POLG alleles (not equal to 10/not equal to 10) was more frequent among the subfertile patients than among fertile controls (P=0.021 and P=0.04 respectively). The estimated predictive value for infertility in a man homozygous for the POLG polymorphism was 15.5% (95% CI: 4.8-51%). There was a positive association with sperm concentration: 14.3% of the normospermic subfertile patients were homozygous for the absence of the common POLG allele (not equal to 10/not equal to 10), in comparison with 2.3% of unselected controls (P=0.001) and 0.9% of the fertile men (P=0.0001). No association with sperm motility, morphology and TTP was found. Spermatozoa of the three not equal to 10/not equal to 10 patients treated with IVF retained the ability to penetrate the egg, but the fertilization rate was low. Nine homozygous not equal to 10/ not equal to 10 patients were treated with ICSI, resulting in pregnancy in seven couples. CONCLUSIONS: The POLG gene polymorphism should be considered as a possible contributing factor in patients with unexplained subfertility and normal spermiograms. The oocyte penetration ability of sperm may be partially impaired in the not equal to 10/not equal to 10 patients but most of them can be successfully treated with ICSI. 相似文献
19.
The researched has dealt with the type of acetylation in 237 TB patients treated with standard course of chemotherapy with a dose of 300 mg of INH in period 1990-1997 in National Research Institute of Tuberculosis and Lung Disease in Warsaw Blood samples were taken before (time 0) and 1, 3, 6 and 24 h after drug administration. Plasma concentrations of isoniazid were determined with biological methods. Two indies of acetylation rate--I3 and C6 have been used to determine an acetylation type. Majority of the treated patients (68.8%) have shown fast type of INH acetylation. After similar dose of isoniazid different profile of absorption and excretion of the drug and significant differences (p < 0.01) in INH concentrations, acetylation rate and bioavailability between 163 fast and 74 slow acetylators have been observed. In plasma of 38.6% fast acetylators drug concentration 3 h after ingestion of a dose did not achieve the concentration of 1 mcg/ml. In plasma of 29.7% slow acetylators, concentrations of INH 6 h after ingestion were higher than 2 mcg/ml. 相似文献
20.
Lynch G Kohler S Leser J Beil M Garcia-Marin LJ Lutz MP 《Pflügers Archiv : European journal of physiology》2004,448(4):445-451
The aim of this study was to establish whether the rate of fatty acid (FA) incorporation and its utilization by the isolated soleus muscle is modified under conditions of thyroid hormone deficit or excess. The rate of palmitic acid (PA) uptake, oxidation and incorporation into intramuscular lipids with increasing PA concentration (0.5–1.5 mM) in the incubation medium were determined. In hypothyroid rats intramuscular triacylglycerol (TG) synthesis was increased, while the rate of PA oxidation to CO2 and incorporation into mono- and diacylglycerols (MG/DG) and phospholipids (PL) remained unchanged. In rats with triiodothyronine (T3) excess the rate of all processes studied was enhanced, although the percentage incorporation of PA into different classes of intramuscular lipids was fairly constant and, independently of thyroid state and FA concentration in the medium, was 56–66% for TG, 9-14% for MG/DG and 24–32% for PL. Our results thus indicate that even short-term T3 excess accelerates the rate of FA uptake and metabolism in the oxidative soleus muscle, whereas in hypothyroid rats only intramuscular TG synthesis is affected. 相似文献