全文获取类型
收费全文 | 27914篇 |
免费 | 1916篇 |
国内免费 | 131篇 |
专业分类
耳鼻咽喉 | 286篇 |
儿科学 | 780篇 |
妇产科学 | 594篇 |
基础医学 | 4229篇 |
口腔科学 | 2532篇 |
临床医学 | 2256篇 |
内科学 | 5616篇 |
皮肤病学 | 601篇 |
神经病学 | 2109篇 |
特种医学 | 609篇 |
外国民族医学 | 1篇 |
外科学 | 3082篇 |
综合类 | 357篇 |
一般理论 | 7篇 |
预防医学 | 3209篇 |
眼科学 | 350篇 |
药学 | 2041篇 |
中国医学 | 281篇 |
肿瘤学 | 1021篇 |
出版年
2023年 | 275篇 |
2022年 | 655篇 |
2021年 | 1064篇 |
2020年 | 733篇 |
2019年 | 922篇 |
2018年 | 1058篇 |
2017年 | 791篇 |
2016年 | 808篇 |
2015年 | 947篇 |
2014年 | 1213篇 |
2013年 | 1447篇 |
2012年 | 2209篇 |
2011年 | 2432篇 |
2010年 | 1279篇 |
2009年 | 964篇 |
2008年 | 1599篇 |
2007年 | 1517篇 |
2006年 | 1382篇 |
2005年 | 1124篇 |
2004年 | 988篇 |
2003年 | 885篇 |
2002年 | 786篇 |
2001年 | 553篇 |
2000年 | 609篇 |
1999年 | 482篇 |
1998年 | 181篇 |
1997年 | 126篇 |
1996年 | 124篇 |
1995年 | 110篇 |
1994年 | 97篇 |
1993年 | 80篇 |
1992年 | 221篇 |
1991年 | 208篇 |
1990年 | 195篇 |
1989年 | 192篇 |
1988年 | 182篇 |
1987年 | 135篇 |
1986年 | 121篇 |
1985年 | 127篇 |
1984年 | 104篇 |
1983年 | 83篇 |
1979年 | 83篇 |
1978年 | 78篇 |
1977年 | 46篇 |
1975年 | 55篇 |
1974年 | 62篇 |
1973年 | 62篇 |
1970年 | 60篇 |
1969年 | 47篇 |
1967年 | 54篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
992.
Leila Cristina Ferreira Silva Angélica Espinosa Miranda Rosieny Santos Batalha Carolina Sabino Elizabeth Cristina Dantas Dib Carolina Marinho da Costa Rajendranath Ramasawmy Sinésio Talhari 《The Brazilian journal of infectious diseases》2012,16(4):335-338
This was a cross-sectional study aimed to determine the prevalence of and to identify risk factors for Chlamydia trachomatis (CT) among human immunodeficiency virus (HIV)-infected women attending the acquired immunodeficiency syndrome (AIDS) clinic in the city of Manaus, Brazil, in 2009-2010. Participants answered a questionnaire containing demographic, epidemiological, and clinical data. A genital specimen was collected during examination to detect CT-DNA by hybrid capture, and blood samples were taken to determine CD4+T and HIV viral load. There were 329 women included in the study. Median age was 32 years (IQR = 27-38) and median schooling was nine years (IQR = 4-11). The prevalence of CT was 4.3% (95%CI: 2.1-6.5). Logistic regression analysis showed that age between 18-29 years [OR = 4.1(95%CI: 1.2-13.4)] and complaint of pelvic pain [OR = 3.7 (95%CI: 1.2-12.8)] were independently associated with CT. The use of condom was inversely associated with CT [OR = 0.39 (95%CI: 0.1-0.9)]. The results showed that younger women who did not use condoms are at a higher risk for CT. Screening for sexually transmitted infections must be done routinely and safe sexual practices should be promoted among this population. 相似文献
993.
Cavalcanti AM Brito AM Salustiano DM Lima KO Silva SP Lacerda HR 《The Brazilian journal of infectious diseases》2012,16(2):157-163
The BED capture enzyme immunoassay test makes it possible to determine whether individuals were recently infected with HIV.ObjectiveIn this study, the overall HIV and recent infections prevalences were determined at five Voluntary Counseling and Testing (VCT) centers, in the Metropolitan Region of Recife, Northeastern of Brazil.Material and methodsA cross-sectional study was conducted among users of five VCTs in the metropolitan region of Recife between July 2007 and April 2009. Out of the individuals who tested positive for HIV, 169 were analyzed to assess the prevalence of recent infection by means of the BED-CEIA (BED-Calypte®).ResultsOut of 46,696 individuals tested 916 (1.96%) turned out positive for HIV infection The highest prevalence was in Recife (3.9%). The prevalence was higher among males (3.93%), and men who have sex with men (MSM) (12.4%). The frequency of recent infections among the 169 subjects evaluated was 23.7%. Recent infections were more common among individuals under 25 years of age. There was slight predominance of men and higher frequency of heterosexuals in both groups, but still a significant portion of MSM (33%). Subtype B predominated, followed by a high proportion of subtype F.ConclusionsRecent infection occurs mainly among young individuals and heterosexuals, despite a significant proportion of recent infection among MSM. These results suggest that preventive actions aimed at the MSM community remains a challenge and efforts focusing this group should continue to be a priority. 相似文献
994.
Rudi Emerson de Lima Procópio Ingrid Reis da Silva Mayra Kassawara Martins João Lúcio de Azevedo Janete Magali de Araújo 《The Brazilian journal of infectious diseases》2012,16(5):466-471
Streptomyces is a genus of Gram-positive bacteria that grows in various environments, and its shape resembles filamentous fungi. The morphological differentiation of Streptomyces involves the formation of a layer of hyphae that can differentiate into a chain of spores. The most interesting property of Streptomyces is the ability to produce bioactive secondary metabolites, such as antifungals, antivirals, antitumorals, anti-hypertensives, immunosuppressants, and especially antibiotics. The production of most antibiotics is species specific, and these secondary metabolites are important for Streptomyces species in order to compete with other microorganisms that come in contact, even within the same genre. Despite the success of the discovery of antibiotics, and advances in the techniques of their production, infectious diseases still remain the second leading cause of death worldwide, and bacterial infections cause approximately 17 million deaths annually, affecting mainly children and the elderly. Self-medication and overuse of antibiotics is another important factor that contributes to resistance, reducing the lifetime of the antibiotic, thus causing the constant need for research and development of new antibiotics. 相似文献
995.
Carvalho VC Oliveira PR Dal-Paz K Paula AP Félix Cda S Lima AL 《The Brazilian journal of infectious diseases》2012,16(1):63-67
IntroductionDespite the growing interest in the study of Gram-negative bacilli (GNB) infections, very little information on osteomyelitis caused by GNB is available in the medical literature.Objectives and methods: To assess clinical and microbiological features of 101 cases of osteomyelitis caused by GNB alone, between January 2007 and January 2009, in a reference center for the treatment of high complexity traumas in the city of São Paulo.ResultsMost patients were men (63%), with median age of 42 years, affected by chronic osteomyelitis (43%) or acute osteomyelitis associated to open fractures (32%), the majority on the lower limbs (71%). The patients were treated with antibiotics as inpatients for 40 days (median) and for 99 days (median) in outpatient settings. After 6 months follow-up, the clinical remission rate was around 60%, relapse 19%, amputation 7%, and death 5%. Nine percent of cases were lost to follow-up. A total of 121 GNB was isolated from 101 clinical samples. The most frequently isolated pathogens were Enterobacter sp. (25%), Acinetobacter baumannii (21%) e Pseudomonas aeruginosa (20%). Susceptibility to carbapenems was about 100% for Enterobacter sp., 75% for Pseudomonas aeruginosa and 60% for Acinetobacter baumannii.ConclusionOsteomyelitis caused by GNB remains a serious therapeutic challenge, especially when associated to nonfermenting bacteria. We emphasize the need to consider these agents in diagnosed cases of osteomyelitis, so that an ideal antimicrobial treatment can be administered since the very beginning of the therapy. 相似文献
996.
997.
Perizzolo PF Dalla Costa ER Ribeiro AW Spies FS Ribeiro MO Dias CF Unis G Almeida da Silva P Gomes HM Suffys PN Rossetti ML 《Tuberculosis (Edinburgh, Scotland)》2012,92(1):56-59
A major threat to tuberculosis (TB) control programs is the emergence of drug resistant Mycobacterium tuberculosis strains that cause TB that cannot be cured by standard anti-TB drug regimens. Because few data exist on MDR-TB in this region of the country, we performed an epidemiologic study that combined conventional and molecular analysis of MDR-TB cases from Rio Grande do Sul (RS) that were diagnosed in this period and included cases that were under treatment with second line drug schemes. Included were 121 MDR cases and sequencing of rpoB and katG showed that 106 (87.6%) strains were mutated in rpoB and 97 (80.2%) in katG. Spoligotyping demonstrated that the LAM genotype was predominant (n?=?70, 57.8%) and included the largest group composed by 22 (18.1%) strains with the LAM5 ST93 genotype. Other main genotypes belonged to the families T (n?=?22, 18.2%), U family (n?=?16, 13.2%), Haarlem (n?=?5, 4.1%) and X (n?=?1, 0.8%). Genotyping by IS6110-RFLP analysis showed 51 distinct fingerprints, 38 (31.4%) of these observed only once and the other 13 patterns being shared among the rest of the isolates (n?=?83, 68.6%). Among the 22 strains that were LAM5 ST93, only two had different IS6110-RFLP genotypes. In conclusion, there exists a high degree of M.?Tuberculosis genotype clustering among MDR-TB cases in Rio Grande do Sul. Moreover, we observed a large MDR-TB outbreak. 相似文献
998.
999.
Introduction
Obstructive sleep apnea–hypopnea syndrome (OSAHS) is an emerging public health concern. Although different treatments for OSAHS had been proposed, continuous positive airway pressure (CPAP) is the first-line treatment in moderate to serious OSAHS in which success can be achieved by increasing compliance to CPAP. 相似文献1000.
Silva Nisa Ferreira André Marques João Heitor Ferreira Natália Correia Nuno Pessoa Bernardete Beirão João Melo Kuhn Ferenc Meireles Angelina 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2021,259(7):1731-1740
Graefe's Archive for Clinical and Experimental Ophthalmology - To assess the outcomes of vitrectomy with or without cataract surgery for the treatment of idiopathic ERM in phakic eyes and... 相似文献