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991.
Park SY Asano M 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(34):12343-12348
The origin recognition complex (ORC) is an essential component of the prereplication complex (pre-RC) in mitotic cell cycles. The role of ORC as a foundation to assemble the pre-RC is conserved from yeast to human. Furthermore, in metazoans ORC plays a key role in determining the timing of replication initiation and origin usage. In this report we have produced and analyzed a Drosophila orc1 allele to investigate the roles of ORC1 in three different modes of DNA replication during development. As expected, ORC1 is essential for mitotic replication and proliferation in brains and imaginal discs, as well as for gene amplification in ovarian follicle cells. Surprisingly, however, ORC1 is not required for endoreplication. Decreased cell number in orc1 mutant salivary glands is consistent with the idea that undetectable levels of maternal ORC1 during embryogenesis fail to support further proliferation. Nevertheless, these cells begin endoreplicating normally and reach a final ploidy of >1000C in the absence of zygotic synthesis of ORC1. The dispensability of ORC is further supported by an examination of other ORC members, whereas Double-parked protein/Cdt1 and minichromosome maintenance proteins are apparently essential for endoreplication, implying that some aspects of initiation are shared among the three modes of DNA replication. This study provides insight into the physiologic roles of ORC during metazoan development and proposes that DNA replication initiation is governed differently in mitotic and endocycles. 相似文献
992.
Association of G-33A polymorphism in the thrombomodulin gene with myocardial infarction in Koreans. 总被引:1,自引:0,他引:1
Hyun-Young Park Toru Nabika Yangsoo Jang Hyuck Moon Kwon Seung Yun Cho Junichi Masuda 《Hypertension research》2002,25(3):389-394
Thrombomodulin (TM), a thrombin receptor expressed on the endothelial surface, is known to play an important role in the anti-thrombogenic system in vivo. In this study, we examined the effects of 3 single-nucleotide polymorphisms (SNPs) in the TM gene (G-33A, C1418T and C1922T) on the development of myocardial infarction (MI) in Koreans. We found that G-33A was a common SNP (the minor allele frequency was 0.09) in Koreans. Eighty-five MI patients who had received coronary angiography were enrolled and were divided into 3 groups according to the number of coronary arteries in which stenosis was found angiographically (1-vessel disease (1VD) to 3-vessel disease (3VD)). The criterion of coronary stenosis was 50% or more stenosis on angiography. In addition, 102 controls (CONT) who had no significant stenosis were employed. The number of AA/GA genotypes of G-33A was found to be significantly greater in the 1VD than in the CONT (p=0.004 by chi2-test) while no significant difference was found between the multivessel disease (2-3VD) and the CONT. Multiple logistic analysis showed that G-33A was an independent risk factor for the 1VD with an odds ratio of 4.63 (95% confidence interval; 1.62-13.3). C1418T and C1922T were both in linkage disequilibrium with G-33A; however, they were not independent risks for either the 1VD or the 2-3VD. A reporter gene assay showed that G-33A had a significant effect on the TM promoter activity. These results indicated that G-33A polymorphism in TM might be a genetic risk factor for myocardial infarction. 相似文献
993.
Oral contraceptive use and hormone replacement therapy are associated with microalbuminuria 总被引:6,自引:0,他引:6
Monster TB Janssen WM de Jong PE de Jong-van den Berg LT;Prevention of Renal Vascular End Stage Disease Study Group 《Archives of internal medicine》2001,161(16):2000-2005
BACKGROUND: Controversy exists regarding the adverse and beneficial effects of oral contraceptive use and hormone replacement therapy. Microalbuminuria is associated with increased risk of renal and cardiovascular disease. OBJECTIVE: To examine the association between oral contraceptive use or hormone replacement therapy and microalbuminuria. METHODS: We performed a case-control study of the baseline data and historical pharmacy data of 4301 female subjects of the Prevention of Renal and Vascular End Stage Disease study cohort, aged 28 to 75 years, excluding women who were pregnant or had type 1 diabetes mellitus. The main outcome measure was microalbuminuria, defined as a urinary albumin excretion of 30 to 300 mg per 24 hours (recorded as the mean of two 24-hour urine collections). RESULTS: After adjusting for age, hypertension, diabetes, obesity, hyperlipidemia, and smoking, the odds ratio (OR) for having microalbuminuria was 1.90 (95% confidence interval [CI], 1.23-2.93) for premenopausal oral contraceptive users and 2.05 (95% CI, 1.12-3.77) for postmenopausal hormone replacement therapy users. The point estimate increased in a dose-dependent fashion, albeit insignificantly, according to the estrogen content of the oral contraceptives (<30 microg ethinyl estradiol: OR, 1.11; 95% CI, 0.14-8.56; 30 to <50 microg: OR, 1.83; 95% CI, 1.17-2.87; and 50 microg: OR, 2.72; 95% CI, 0.81-9.08). The OR was greater in oral contraceptives with a second-generation (OR, 2.04; 95% CI, 1.28-3.25) vs a third-generation progestin (OR, 1.39; 95% CI, 0.63-3.06). The OR increased with the duration of hormone replacement therapy (< or =5 years, OR, 1.28; 95% CI, 0.37-4.50; >5 years, OR, 2.56; 95% CI, 1.32-4.97). CONCLUSION: Regular and long-term oral contraceptive use and hormone replacement therapy are associated with an increased risk for microalbuminuria and cardiovascular disease. 相似文献
994.
Arrhythmogenic right ventricular cardiomyopathy and sudden cardiac death in young Koreans. 总被引:1,自引:0,他引:1
Yongkeun Cho Taein Park Dong Heon Yang Hun-Sik Park Jongmin Chae Shung-Chull Chae Jae-Eun Jun Jyung-Sik Kwak Wee-Hyun Park 《Circulation journal》2003,67(11):925-928
The aim of this study was to assess the frequency and clinical characteristics of arrhythmogenic right ventricular cardiomyopathy (ARVC) in young victims of sudden cardiac death (SCD). From January 1999 to December 2000, postmortem studies were conducted in 38 cases of SCD (age < or =35 (27+/-7) years old, 26 male) from the Taegu-Kyungpook region of southeastern Korea. Cases of sudden infant death syndrome were excluded. The causes of SCD were ARVC in 42%, acute myocardial infarction in 11%, myocarditis in 11%, pulmonary embolism in 8%, hypertrophic cardiomyopathy in 5%, aortic rupture in 3%, aortic stenosis in 3%, and unknown in 18%. The mean age of the 16 ARVC victims was 27+/-5 years and 10 were male. None were competitive athletes, or had been suspected of having cardiovascular disease before death. SCD was not related to vigorous physical or competitive activity and occurred during sleep in 7 cases, during work in 4, during bathing in 2, while driving, praying and eating in 1 case each. ARVC is an important cause of SCD in young people in this area of Korea. 相似文献
995.
Jong Min Park Won Hee Lee Hochan Seo Ji Young Oh Dong Yoon Lee Seong Jin Kim Ki Baik Hahm 《Journal of Clinical Biochemistry and Nutrition》2021,68(2):139
Gut bacteria might contribute in early stage of colorectal cancer through the development and advancement of colon adenoma, by which exploring either beneficial bacteria, which are decreased in formation or advancement of colon adenoma and harmful bacteria, which are increased in advancement of colon adenoma may result in implementation of dietary interventions or probiotic therapies to functional means for prevention. Korean fermented kimchi is one of representative probiotic food providing beneficiary microbiota and exerting significant inhibitory outcomes in both APC/Min+ polyposis model and colitis-associated cancer. Based on these backgrounds, we performed clinical trial to document the changes of fecal microbiota in 32 volunteers with normal colon, simple adenoma, and advanced colon adenoma with 10 weeks of fermented kimchi intake. Each amplicon is sequenced on MiSeq of Illumina and the sequence reads were clustered into Operational Taxonomic Units using VSEARCH and the Chao Indices, an estimator of richness of taxa per individual, were estimated to measure the diversity of each sample. Though significant difference in α or β diversity was not seen between three groups, kimchi intake significantly led to significant diversity of fecal microbiome. After genus analysis, Acinobacteria, Cyanobacteria, Clostridium sensu, Turicibacter, Gastronaeophillales, H. pittma were proven to be increased in patients with advanced colon adenoma, whereas Enterococcua Roseburia, Coryobacteriaceau, Bifidobacterium spp., and Akkermansia were proven to be significantly decreased in feces from patients with advanced colon adenoma after kimchi intake. Conclusively, fermented kimchi plentiful of beneficiary microbiota can afford significant inhibition of either formation or advancement of colon adenoma. 相似文献
996.
Jiwon Jung Sophia T. Mundle Irina V. Ustyugova Andrew P. Horton Daniel R. Boutz Svetlana Pougatcheva Ponraj Prabakaran Jonathan R. McDaniel Gregory R. King Daechan Park Maria D. Person Congxi Ye Bing Tan Yuri Tanno Jin Eyun Kim Nicholas C. Curtis Joshua DiNapoli Simon Delagrave Ted M. Ross Gregory C. Ippolito Harry Kleanthous Jiwon Lee George Georgiou 《The Journal of clinical investigation》2021,131(13)
Seasonal influenza vaccination elicits a diminished adaptive immune response in the elderly, and the mechanisms of immunosenescence are not fully understood. Using Ig-Seq, we found a marked increase with age in the prevalence of cross-reactive (CR) serum antibodies that recognize both the H1N1 (vaccine-H1) and H3N2 (vaccine-H3) components of an egg-produced split influenza vaccine. CR antibodies accounted for 73% ± 18% of the serum vaccine responses in a cohort of elderly donors, 65% ± 15% in late middle-aged donors, and only 13% ± 5% in persons under 35 years of age. The antibody response to non-HA antigens was boosted by vaccination. Recombinant expression of 19 vaccine-H1+H3 CR serum monoclonal antibodies (s-mAbs) revealed that they predominantly bound to non-HA influenza proteins. A sizable fraction of vaccine-H1+H3 CR s-mAbs recognized with high affinity the sulfated glycans, in particular sulfated type 2 N-acetyllactosamine (Galβ1-4GalNAcβ), which is found on egg-produced proteins and thus unlikely to contribute to protection against influenza infection in humans. Antibodies against sulfated glycans in egg-produced vaccine had been identified in animals but were not previously characterized in humans. Collectively, our results provide a quantitative basis for how repeated exposure to split influenza vaccine correlates with unintended focusing of serum antibody responses to non-HA antigens that may result in suboptimal immunity against influenza. 相似文献
997.
Kuen Su Lee Yoo Kyung Jang Gene Hyun Park In Jae Jun Jae Chul Koh 《The Journal of international medical research》2021,49(3)
Spinal cord stimulation (SCS) has been used to treat sustained pain that is intractable despite various types of treatment. However, conventional tonic waveform SCS has not shown promising outcomes for spinal cord injury (SCI) or postamputation pain. The pain signal mechanisms of burst waveforms are different to those of conventional tonic waveforms, but few reports have presented the therapeutic potential of burst waveforms for the abovementioned indications. This current case report describes two patients with refractory upper limb pain after SCI and upper limb amputation that were treated with burst waveform SCS. While the patients could not obtain sufficient therapeutic effect with conventional tonic waveforms, the burst waveforms provided better pain reduction with less discomfort. However, further studies are necessary to better clarify the mechanisms and efficacy of burst waveform SCS in patients with intractable pain. 相似文献
998.
A Mi Kim Jong Woon Kim Yoon Ha Kim Tae Young Kim Hyun Kyung Ryu Myeong Gyun Choi 《The Journal of international medical research》2021,49(3)
IntroductionSonography and magnetic resonance imaging (MRI) may be helpful to obtain an accurate diagnosis of acute abdominal pain in pregnancy. Adnexal torsion presenting in the first or second trimester can be confirmed and treated through laparoscopic surgery; however laparoscopic surgery in the third trimester can be difficult owing to the large uterus, and a gridiron incision can be useful.Case Report/Case presentationAn 18-year-old gravida 1, para 0 (G1P0) woman at 30 + 4 weeks of gestation presented with sudden-onset cyclic pain in the right lower quadrant. Abdominal ultrasonography showed a normal appendix, and MRI showed a normal appendix and normal ovaries. The patient’s prominent tender point was marked and compared with the MR images, which confirmed the mark as the position of the right ovary. Laparotomy was performed through a gridiron incision, and a folded right ovary was identified. The ovary was unfolded, and TachoSil® and Surgicel® were used to maintain the unfolded position. The patient’s pain resolved, and her postoperative course was uneventful. She delivered a healthy, 2540-g male baby at 35 weeks’ gestation.Discussion/ConclusionsA gridiron incision was useful to treat a folded ovary in the third trimester and to evaluate the adnexa and minimize uterine manipulation. 相似文献
999.