全文获取类型
收费全文 | 9398篇 |
免费 | 530篇 |
国内免费 | 82篇 |
专业分类
耳鼻咽喉 | 123篇 |
儿科学 | 205篇 |
妇产科学 | 172篇 |
基础医学 | 1155篇 |
口腔科学 | 897篇 |
临床医学 | 763篇 |
内科学 | 2134篇 |
皮肤病学 | 209篇 |
神经病学 | 663篇 |
特种医学 | 363篇 |
外科学 | 915篇 |
综合类 | 33篇 |
一般理论 | 4篇 |
预防医学 | 1016篇 |
眼科学 | 163篇 |
药学 | 730篇 |
1篇 | |
中国医学 | 97篇 |
肿瘤学 | 367篇 |
出版年
2023年 | 86篇 |
2022年 | 232篇 |
2021年 | 350篇 |
2020年 | 246篇 |
2019年 | 290篇 |
2018年 | 357篇 |
2017年 | 232篇 |
2016年 | 258篇 |
2015年 | 332篇 |
2014年 | 468篇 |
2013年 | 497篇 |
2012年 | 676篇 |
2011年 | 823篇 |
2010年 | 396篇 |
2009年 | 331篇 |
2008年 | 546篇 |
2007年 | 585篇 |
2006年 | 406篇 |
2005年 | 406篇 |
2004年 | 311篇 |
2003年 | 295篇 |
2002年 | 253篇 |
2001年 | 167篇 |
2000年 | 152篇 |
1999年 | 132篇 |
1998年 | 83篇 |
1997年 | 91篇 |
1996年 | 87篇 |
1995年 | 61篇 |
1994年 | 45篇 |
1993年 | 45篇 |
1992年 | 46篇 |
1991年 | 76篇 |
1990年 | 57篇 |
1989年 | 55篇 |
1988年 | 57篇 |
1987年 | 57篇 |
1986年 | 49篇 |
1985年 | 53篇 |
1984年 | 35篇 |
1983年 | 37篇 |
1982年 | 26篇 |
1981年 | 21篇 |
1980年 | 25篇 |
1979年 | 18篇 |
1978年 | 15篇 |
1977年 | 16篇 |
1975年 | 14篇 |
1973年 | 15篇 |
1966年 | 13篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Transfection of human macrophages by lipoplexes via the combined use of transferrin and pH-sensitive peptides 总被引:10,自引:0,他引:10
Simões S Slepushkin V Pretzer E Dazin P Gaspar R Pedroso de Lima MC Düzgüneş N 《Journal of leukocyte biology》1999,65(2):270-279
The crucial function of macrophages in a variety of biological processes and pathologies render these cells important targets for gene therapeutic interventions. Commonly used synthetic gene delivery vectors have not been successful in transfecting these non-dividing cells. A combination strategy involving cationic liposomes to condense and carry DNA, transferrin to facilitate cellular uptake, and the pH-sensitive peptide GALA to promote endosome destabilization, resulted in significant expression of a luciferase gene. Transfection of macrophages was dependent on the degree of differentiation of the cells. The quaternary complexes of cationic liposomes, DNA, transferrin, and GALA exhibited a net negative charge, which may obviate a limitation of cationic synthetic vectors in vivo. The lack of cytotoxicity and the expected lack of immunogenicity of these complexes may render them useful for gene delivery to macrophages in vivo. 相似文献
52.
C. B. Laval A. L. S. S. de rade F. C. Pimenta J. G. de Andrade R. M. de Oliveira S. A. Silva E. C. de Lima J. L. Di Fabio S. T. Casagrande M. C. C. Brandileone 《Clinical microbiology and infection》2006,12(1):50-55
Nasopharyngeal carriage of Streptococcus pneumoniae is a key factor in the development of invasive disease and the spread of resistant strains within the community. A single nasopharyngeal swab was obtained from 648 unvaccinated children aged <5 years, either healthy or with acute respiratory tract infection or meningitis, during the winters of 2000 and 2001. The overall pneumococcal carriage rate was 35.8% (95% CI 32.1-39.6). The pneumococcal serotypes found most frequently in the nasopharynx were 14, 6B, 6A, 19F, 10A, 23F and 18C, which included five of the seven serotypes in the currently licensed seven-valent conjugate vaccine (PCV7); serotypes 4 and 9V were less common. Serotypes 1 and 5 were isolated rarely from the nasopharynx. A comparison of 222 nasopharyngeal isolates with 125 invasive isolates, matched for age and time to the carrier isolates, showed a similar prevalence of penicillin non-susceptible pneumococci (PNSp) (19.8% and 19.2%, respectively). PNSp serotypes were similar (6B, 14, 19F, 19 A, 23B and 23F) for carriage and invasive disease isolates. The coverage of PCV7 for carriage isolates (52.2%) and invasive isolates (62.4%) did not differ significantly (p 0.06); similarly, there was no significant difference in PCV7 coverage for carriage isolates (34.5%) and invasive isolates (28.2%) of PNSp. These data suggest that PCV7 has the potential to reduce pneumococcal carriage and the number of carriers of PNSp belonging to vaccine serotypes. 相似文献
53.
Matte U Yogalingam G Brooks D Leistner S Schwartz I Lima L Norato DY Brum JM Beesley C Winchester B Giugliani R Hopwood JJ 《Molecular genetics and metabolism》2003,78(1):37-43
In this study we have investigated a group of 29 Brazilian patients, who had been diagnosed with the lysosomal storage disorder, Mucopolysaccharidosis type I (MPS-I). MPS I is caused by a deficiency in the lysosomal hydrolase, alpha-L-iduronidase. Ninety percent of the MPS I patients in this study were genotyped and revealed 10 recurrent and thirteen novel IDUA gene mutations. Eight of these new mutations and three common mutations W402X, P533R, and R383H were individually expressed in CHO-K1 cells and analyzed for alpha-L-iduronidase protein and enzyme activity. A correlation was observed between the MPS I patient clinical phenotype and the associated mutant alpha-L-iduronidase protein/enzyme activity expressed in CHO-K1 cells. This was the first time that Brazilian MPS I patients had been thoroughly analyzed and highlighted the difficulties of mutation screening and clinical phenotype assessment in populations with high numbers of unique mutations. 相似文献
54.
55.
56.
57.
58.
Stamborowski Sadi Fernando de Oliveira Spinelli Bruna Moreira Lima Fernanda Pupio Silva Costa Davidson Ribeiro de Silveira Souza Gabriela Aparecida Lima Mario Oliveira Lopes Martins Rodrigo Alvaro Brandão 《Lasers in medical science》2021,36(8):1741-1749
Lasers in Medical Science - Physical activity raises body temperature. However, the literature does not contain studies about whether the employment of hotobiomodulation (PMB) could significantly... 相似文献
59.
André Luís Conde Watanabe Mateus Silva Feijó Vinícius Paulo Lima de Menezes Mayara Regina Galdino-Vasconcelos Jorge Luis Salinas Caballero Gustavo Ferreira Fernando Jorge Natália Trevizoli Luiz Gustavo Diaz Priscila Brizolla de Campos Gabriel Cajá Raquel Ullmann Ana Virgínia Figueira Tiago Morato Adriano Moraes Juan Rafael Branez Pereira Marcelo Perosa 《Transplantation proceedings》2021,53(1):73-82
IntroductionLiver transplantation is the standard treatment for end-stage liver disease. Brazil holds the third highest number of liver transplants performed per year, but center maldistribution results in high discrepancies in accessing this treatment. In 2012, an interstate partnership successfully implemented a new liver transplantation program in the middle west of Brazil. Here, we report the results of the first 500 liver transplants performed in this new program and discuss the impacts of a new transplant center in regional transplantation dynamics.MethodsWe reviewed data from the first 500 consecutive deceased donor liver transplants performed in the new program during an 8-year period. We analyzed data on patients’ clinical and demographic profiles, postoperative outcomes, and graft and recipient survival rates. Univariate survival analysis was conducted using log-rank tests to compare the groups.ResultsAlmost half (48%) of the procured organs and 40% of the recipients transplanted in our center were from outside our state. Recipient 30-day mortality was 9%. Overall recipient survival at 1 year and 5 years was 85% and 80%, respectively. Mortality was significantly associated with higher Model for End-Stage Liver Disease (P < .001) but not with the presence of hepatocellular carcinoma (P = .795).DiscussionThe new transplantation program treated patients from different regions of Brazil and became the reference center in liver transplantation for the middle west region. Despite the recent implementation, our outcomes are comparable to experienced centers around the world. This model can inspire the creation of new transplantation programs aiming to democratize access to liver transplantation nationwide. 相似文献
60.
Rania El Fekih James Hurley Vasisht Tadigotla Areej Alghamdi Anand Srivastava Christine Coticchia John Choi Hazim Allos Karim Yatim Juliano Alhaddad Siawosh Eskandari Philip Chu Albana B. Mihali Isadora T. Lape Mauricio P. Lima Filho Bruno T. Aoyama Anil Chandraker Kassem Safa James F. Markmann Leonardo V. Riella Richard N. Formica Johan Skog Jamil R. Azzi 《Journal of the American Society of Nephrology : JASN》2021,32(4):994
BackgroundDeveloping a noninvasive clinical test to accurately diagnose kidney allograft rejection is critical to improve allograft outcomes. Urinary exosomes, tiny vesicles released into the urine that carry parent cells’ proteins and nucleic acids, reflect the biologic function of the parent cells within the kidney, including immune cells. Their stability in urine makes them a potentially powerful tool for liquid biopsy and a noninvasive diagnostic biomarker for kidney-transplant rejection.MethodsUsing 192 of 220 urine samples with matched biopsy samples from 175 patients who underwent a clinically indicated kidney-transplant biopsy, we isolated urinary exosomal mRNAs and developed rejection signatures on the basis of differential gene expression. We used crossvalidation to assess the performance of the signatures on multiple data subsets.ResultsAn exosomal mRNA signature discriminated between biopsy samples from patients with all-cause rejection and those with no rejection, yielding an area under the curve (AUC) of 0.93 (95% CI, 0.87 to 0.98), which is significantly better than the current standard of care (increase in eGFR AUC of 0.57; 95% CI, 0.49 to 0.65). The exosome-based signature’s negative predictive value was 93.3% and its positive predictive value was 86.2%. Using the same approach, we identified an additional gene signature that discriminated patients with T cell–mediated rejection from those with antibody-mediated rejection (with an AUC of 0.87; 95% CI, 0.76 to 0.97). This signature’s negative predictive value was 90.6% and its positive predictive value was 77.8%.ConclusionsOur findings show that mRNA signatures derived from urinary exosomes represent a powerful and noninvasive tool to screen for kidney allograft rejection. This finding has the potential to assist clinicians in therapeutic decision making. 相似文献