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991.
992.
Pelin Sahlén Rapolas Spalinskas Samina Asad Kunal Das Mahapatra Pontus Höjer Anandashankar Anil Jesper Eisfeldt Ankit Srivastava Pernilla Nikamo Anaya Mukherjee Kyu-Han Kim Otto Bergman Mona Ståhle Enikö Sonkoly Andor Pivarcsi Carl-Fredrik Wahlgren Magnus Nordenskjöld Fulya Taylan Isabel Tapia-Páez 《The Journal of allergy and clinical immunology》2021,147(5):1742-1752
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993.
Marsit CJ Wiencke JK Nelson HH Kim DH Hinds PW Aldape K Kelsey KT 《Cancer Genetics and Cytogenetics》2005,162(2):115-121
Tobacco smoke is well recognized as the major etiological contributor to lung cancer, yet the relationship between tobacco smoke exposure and a specific pattern of molecular abnormalities at somatic loci is less well characterized. We analyzed 100 primary tumors from patients undergoing surgical resection of squamous cell carcinoma and adenocarcinoma of the lung for loss of heterozygosity (LOH) and homozygous deletions at two microsatellite markers in a recombinogenic region of 9p13. We describe the relationship of alterations at these markers with tumor characteristics (both clinical and molecular), patient demographics, survival, and measures of tobacco-smoke exposure. Homozygous deletions in this region occurred in 25% (21/85) and LOH in 33% (28/85) of informative tumors examined. These alterations occurred more often in tumors with intense TP53 protein staining by immunohistochemistry, suggesting that inactivation of the TP53 pathway may contribute to these LOH events. Duration of smoking was greatest in patients with the homozygous deletion, intermediate in patients with LOH, and shortest in patients whose tumor did not demonstrate loss in these markers. Unexpectedly, LOH at 9p13 was a significant predictor of improved survival in patients, while the homozygous deletion was associated with the poorest patient survival. Together, these results suggest that TP53 alteration and long-term tobacco smoke exposure may contribute to genetic alterations at 9p13, and that the mechanism and biologic consequences of allele loss reflect individual biologic differences that determine the extent of loss (LOH or homozygous deletion), such that those patients with the deletion of this region face a more aggressive and deadly disease. 相似文献
994.
Su-Yeon Kang Kyoung-Ju Song Seok-Ryoul Jeong Jong-Hyun Kim Sun Park Kyongmin Kim Myung-Hee Kwon Ho-Joon Shin 《Clinical and Vaccine Immunology : CVI》2005,12(7):873-876
Naegleria fowleri, a free-living amoeba, exists as a virulent pathogen which causes fatal primary amoebic meningoencephalitis in experimental animals and humans. Using infected and immune mouse sera, we previously cloned an nfa1 gene from a cDNA library of N. fowleri by immunoscreening. The nfa1 gene (360 bp) produced a recombinant 13.1-kDa protein, and the Nfa1 protein showed pseudopodium-specific immunolocalization on a trophozoite of N. fowleri. In this study, the role of the Nfa1 protein as a cell contact mechanism of N. fowleri cocultured with target cells was observed by an immunofluorescence assay with an anti-Nfa1 polyclonal antibody. Using confocal microscopic findings, the Nfa1 protein was located on the pseudopodia of N. fowleri trophozoites. The Nfa1 protein in N. fowleri trophozoites cocultured with CHO target cells was also located on pseudopodia, as well as in a food cup formed as a phagocytic structure in close contact with target cells. The amount of nfa1 mRNA of N. fowleri was strongly increased 6 h after coculture. 相似文献
995.
Morse MA Garst J Osada T Khan S Hobeika A Clay TM Valente N Shreeniwas R Sutton MA Delcayre A Hsu DH Le Pecq JB Lyerly HK 《Journal of translational medicine》2005,3(1):9-8
BACKGROUND: There is a continued need to develop more effective cancer immunotherapy strategies. Exosomes, cell-derived lipid vesicles that express high levels of a narrow spectrum of cell proteins represent a novel platform for delivering high levels of antigen in conjunction with costimulatory molecules. We performed this study to test the safety, feasibility and efficacy of autologous dendritic cell (DC)-derived exosomes (DEX) loaded with the MAGE tumor antigens in patients with non-small cell lung cancer (NSCLC). METHODS: This Phase I study enrolled HLA A2+ patients with pre-treated Stage IIIb (N = 4) and IV (N = 9) NSCLC with tumor expression of MAGE-A3 or A4. Patients underwent leukapheresis to generate DC from which DEX were produced and loaded with MAGE-A3, -A4, -A10, and MAGE-3DPO4 peptides. Patients received 4 doses of DEX at weekly intervals. RESULTS: Thirteen patients were enrolled and 9 completed therapy. Three formulations of DEX were evaluated; all were well tolerated with only grade 1-2 adverse events related to the use of DEX (injection site reactions (N = 8), flu like illness (N = 1), and peripheral arm pain (N = 1)). The time from the first dose of DEX until disease progression was 30 to 429+ days. Three patients had disease progression before the first DEX dose. Survival of patients after the first DEX dose was 52-665+ days. DTH reactivity against MAGE peptides was detected in 3/9 patients. Immune responses were detected in patients as follows: MAGE-specific T cell responses in 1/3, increased NK lytic activity in 2/4. CONCLUSION: Production of the DEX vaccine was feasible and DEX therapy was well tolerated in patients with advanced NSCLC. Some patients experienced long term stability of disease and activation of immune effectors. 相似文献
996.
The etiology of systemic lupus erythematosus (SLE) is very complex, and genetic factors appear to play a significant role in susceptibility to SLE, in determining the disease expression, and in the autoantibody profiles of individuals with SLE. DNA methyltransferase-1 (DNMT1) is a major enzyme that determines genomic methylation patterns and both maintains methyltransferase and exhibits de novo DNA methylation activity in vivo. In order to clarify the association of DNMT1 polymorphisms with SLE, we scrutinized the genetic polymorphisms in exons and their boundaries of DNMT1, including the –1,500 bp promoter region, by direct sequencing in 24 Korean individuals. Twenty-nine sequence variants were identified: two in 5UTR, six in exons, and 21 in introns. Eight of these polymorphisms were selected for a larger-scale genotyping (n=680) by considering their allele frequencies, haplotype-tagging status, and linkage disequilibrium coefficiencies (LDs) among polymorphisms. The associations between DNMT1 polymorphisms and the clinical profiles of SLE were analyzed. No significant associations with the risk of SLE were detected. However, further analyses of association with autoantibody production among SLE patients revealed that one nonsynonymous SNP, +14463G>C (V120L) in exon 4, was weakly associated with an increased risk of anti-La antibody production (P=0.04), although the significance could not be retained after correction of multiple tests. The DNMT1 variations and haplotypes clarified in this study would provide valuable information for future genetic studies of other autoimmune diseases. 相似文献
997.
Mechanism of bonelike apatite formation on bioactive tantalum metal in a simulated body fluid. 总被引:3,自引:0,他引:3
Toshiki Miyaza Hyun-Min Kim Tadashi Kokubo Chikara Ohtsuki Hirofumi Kato Takashi Nakamura 《Biomaterials》2002,23(3):827-832
Development of tantalum metal with bone-bonding ability is paid much attention because of its attractive features such as high fracture toughness, high workability and its achievement on clinical usage. Formation of bonelike apatite is an essential prerequisite for artificial materials to make direct bond to living bone. The apatite formation can be assessed in vitro using a simulated body fluid (SBF) that has almost equal compositions of inorganic ions to human blood plasma. The present authors previously showed that the apatite formation on tantalum metal in SBF was remarkably accelerated by treatment with NaOH aqueous solution and subsequent firing at 300 degrees C, while untreated tantalum metal spontaneously forms the apatite after a long soaking period. The purpose of the present study is to clarify the reason why the NaOH and heat treatments accelerate the apatite formation on tantalum metal. X-ray photoelectron spectroscopy was used to analyze changes in surface structure of the tantalum metal at an initial stage after immersion in SBF. Untreated tantalum metal had tantalum oxide passive layer on its surface, while amorphous sodium tantalate was formed on the surface of the tantalum metal by the NaOH and heat treatments. After soaking in SBF, the untreated tantalum metal sluggishly formed small amount of Ta-OH groups by a hydration of the tantalum oxide passive layer on its surface. In contrast, the treated tantalum metal rapidly formed Ta-OH groups by exchange of Na+ ion in the amorphous sodium tantalate on its surface with H3O+ ion in SBF. Both the formed Ta-OH groups combined with Ca2+ ion to form a kind of calcium tantalate, and then with phosphate ion, followed by combination with large amount of Ca2+ ions and phosphate ions to build up apatite layer. The formation rate of Ta-OH groups on the treated tantalum metal predominates the following process including adsorption of Ca2+ ion and phosphate ion on the surface. It is concluded that the acceleration of the apatite nucleation on the tantalum metal in SBF by the NaOH and heat treatments was attributed to the fast formation of Ta-OH group, followed by combination of the Ta-OH groups with Ca2+ and phosphate ions. 相似文献
998.
Effects of nocturnal bright light on saliva melatonin, core body temperature and sleep propensity rhythms in human subjects 总被引:1,自引:0,他引:1
Kubota T Uchiyama M Suzuki H Shibui K Kim K Tan X Tagaya H Okawa M Inoue S 《Neuroscience research》2002,42(2):115-122
Nine healthy male volunteers (mean age of 24) participated in two experimental sessions of random crossover design: a bright light (5000 lux for 5 h from 00:00 to 05:00 h) session and a dim light (10 lux for 5 h from 00:00 to 05:00 h) session. Subsequently participants entered an ultra-short sleep-wake schedule for 26 h, in which a sleep-wake cycle consisting of 10-min sleep EEG recording on a bed and 20-min resting awake on a semi-upright chair were repeated. Saliva melatonin level and core body temperature was measured throughout the experiment. Bright light significantly delayed rhythms of melatonin secretion (01:58 h), core body temperature (01:12 h) and sleep propensity (02:00 h), compared as dim light session. Significant positive correlation was found between bright light-induced phase change in core body temperature and that in sleep propensity rhythm. Light-induced melatonin suppression significantly positively correlated with the phase change in core body temperature and that in sleep propensity rhythm. Assuming that light-induced melatonin suppression represents an acute impact of light on the circadian pacemaker, our results suggest that such an impact may be directly reflected in phase changes of sleep propensity and core body temperature rhythms rather than in melatonin rhythm. 相似文献
999.
Hong KE Ock SM Kang MH Kim CE Bae JN Lim MK Suh CH Chung SJ Cho SC Lee JS 《Journal of Korean medical science》2002,17(4):530-536
Neuropathological deficits are an etiological factor in Tourette syndrome (TS), and implicate a network linking the basal ganglia and the cerebrum, not a particular single brain region. In this study, the volumes of 20 cerebral and cerebellar regions and their symmetries were measured in normal boys and TS boys by brain magnetic resonance imaging. Brain magnetic resonance images were obtained prospectively in 19 boys with TS and 17 age-matched normal control boys. Cerebral and cerebellar regions were segmented to gray and white fractions using algorithm for semi-automated fuzzy tissue segmentation. The frontal, parietal, temporal, and the occipital lobes and the cerebellum were defined using the semiautomated Talairach atlas-based parcellation method. Boys with TS had smaller total brain volumes than control subjects. In the gray matter, although the smaller brain volume was taken into account, TS boys had a smaller right frontal lobe and a larger left frontal lobe and increased normal asymmetry (left>right). In addition, TS boys had more frontal lobe white matter. There were no significant differences in regions of interest of the parietal, temporal, or the occipital lobes or the cerebellum. These findings suggest that boys with TS may have neuropathological abnormalities in the gray and the white matter of the frontal lobe. 相似文献
1000.
Esophageal ulceration triggers expression of hypoxia-inducible factor-1 alpha and activates vascular endothelial growth factor gene: implications for angiogenesis and ulcer healing
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Baatar D Jones MK Tsugawa K Pai R Moon WS Koh GY Kim I Kitano S Tarnawski AS 《The American journal of pathology》2002,161(4):1449-1457