全文获取类型
收费全文 | 7411篇 |
免费 | 432篇 |
国内免费 | 28篇 |
专业分类
耳鼻咽喉 | 80篇 |
儿科学 | 163篇 |
妇产科学 | 134篇 |
基础医学 | 1029篇 |
口腔科学 | 942篇 |
临床医学 | 569篇 |
内科学 | 1628篇 |
皮肤病学 | 138篇 |
神经病学 | 465篇 |
特种医学 | 201篇 |
外科学 | 744篇 |
综合类 | 25篇 |
预防医学 | 810篇 |
眼科学 | 118篇 |
药学 | 510篇 |
中国医学 | 70篇 |
肿瘤学 | 245篇 |
出版年
2023年 | 72篇 |
2022年 | 186篇 |
2021年 | 263篇 |
2020年 | 199篇 |
2019年 | 250篇 |
2018年 | 322篇 |
2017年 | 195篇 |
2016年 | 220篇 |
2015年 | 276篇 |
2014年 | 348篇 |
2013年 | 418篇 |
2012年 | 602篇 |
2011年 | 683篇 |
2010年 | 314篇 |
2009年 | 302篇 |
2008年 | 409篇 |
2007年 | 463篇 |
2006年 | 355篇 |
2005年 | 297篇 |
2004年 | 237篇 |
2003年 | 193篇 |
2002年 | 188篇 |
2001年 | 133篇 |
2000年 | 117篇 |
1999年 | 114篇 |
1998年 | 32篇 |
1997年 | 16篇 |
1996年 | 20篇 |
1995年 | 15篇 |
1994年 | 23篇 |
1993年 | 14篇 |
1992年 | 46篇 |
1991年 | 54篇 |
1990年 | 34篇 |
1989年 | 45篇 |
1988年 | 31篇 |
1987年 | 39篇 |
1986年 | 38篇 |
1985年 | 27篇 |
1984年 | 28篇 |
1983年 | 24篇 |
1982年 | 20篇 |
1979年 | 15篇 |
1977年 | 16篇 |
1976年 | 13篇 |
1975年 | 15篇 |
1971年 | 14篇 |
1970年 | 20篇 |
1968年 | 20篇 |
1967年 | 13篇 |
排序方式: 共有7871条查询结果,搜索用时 0 毫秒
1.
Joseane Balan Da Silva Gleison Daion Piovezana Bossolani Camila Piva Greicy Brisa Malaquias Dias Jancarlo Gomes Ferreira Diogo Francisco Rossoni 《International journal of environmental health research》2016,26(5-6):578-588
The spatial distribution of enteroparasitosis in an indigenous village from Paraná was evaluated to identify areas of risk for these infections. A cross-sectional study (from November 2010 to June 2011) was performed using Three Faecal Test® and Kato &; Katz method and a questionnaire on housing and hygiene conditions was administered. Local geostatistical analyses were performed to determine the spatial distribution of intestinal parasitic infections. The overall prevalence of enteroparasites was 67.2?% (457/680), and the most prevalent taxa were Ascaris lumbricoides (48.8?%) and Trichuris trichiura (44.7?%). The prevalence of heavy infection by soil-transmitted helminths was 3.6?% and the families lived in houses with an average of 5.1 residents and < 2 bedrooms per household. The average number of species per individual present spatial heterogeneity with the highest values (≥0.8) in areas with high clustering of residences. The visualization of the spatial distribution of intestinal parasites in this indigenous village is an important contribution to determining health risk areas and planning decisions and services. 相似文献
2.
The antiproliferative, cytotoxic and apoptogenic activities of Bufo melanostictus (Indian common toad) skin extract (TSE) on U937 and K562 leukemic cell line has been investigated. TSE significantly (P<0.001) reduced the time-dependent cell proliferation and decreased MTT values in U937 and K562 cells. TSE (IC50 doses) suppressed the proliferating cell nuclear antigen expression in both the cells. It was demonstrated that, TSE (IC50 doses) primarily arrested the U937 and K562 cells at G1 phase of the cell cycle. Confocal microscopy showed the altered fragmented nuclei and apoptotic bodies formation in TSE (IC50 doses) treated U937 and K562 cells. Membrane blebbing, cell surface shrinkage and perforation were observed through scanning electron microscope. TSE-induced DNA fragmentation in U937 and K562 cells was reflected in single-cell gel electrophoresis. TSE significantly (P<0.001) increase the length-width ratio of DNA mass as compared to control in comet assay. The flow cytometric analysis of annexin-V binding to the cancer cells further supported the apoptotogenic activity of TSE. The effect of TSE on normal human peripheral blood mononuclear cells viability and cytotoxicity was studied in culture and found to be less cytotoxic than on the U937 and K562 cells. The findings from the present study suggested that TSE might possess potent antineoplastic agent having antiproliferative, cytotoxic and apoptogenic activity against U937 and K562 myeloid leukemic cells. 相似文献
3.
4.
5.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
6.
7.
Anya Pimentel Gomes Fernandes Vieira Jose Maria Sampaio Meneses Jr Renato Luiz Maia 《Journal of oral pathology & medicine》2007,36(2):117-119
Cementoblastomas are benign lesions of the odontogenic ectomesenchyme that rarely occur related to the primary dentition, especially on the left side of the mandible. This study describes a case of a true cementoblastoma related to the left second primary mandibular molar in a 7-year-old child (the largest one seen in the left side of the mandible). Additionally, the radiographic and histologic findings of the lesion are described in details. 相似文献
8.
F. M. O. Silva J. E. Vergara‐Parente J. K. N. Gomes M. N. Teixeira R. P. Lima 《Transboundary and Emerging Diseases》2007,54(3):119-122
Serum chemistry analyses represents a fundamental tool for the diagnosis and understanding of diseases in marine mammals. Although several studies are being conducted within the field of clinical pathology, haematological and serum chemistry data for Antillean manatees are deficient. The purpose of this study was to determine serum chemistry values for captive Antillean manatees within the CMA/Ibama facility in Brazil. Serum samples were obtained from five captive adult Antillean manatees fed with seagrass and analysed for aspartate aminotransferase, alanine aminotransferase, bilirubin, alkaline phosphatase, urea, creatinine, glucose, triglycerides, cholesterol, total protein, albumin, globulin, phosphate, chloride, calcium and uric acid. Blood chemistry parameters were determined using a semi‐automatic analyzer. Maximum, minimum, mean and standard deviations were calculated for each serum chemistry parameter. Differences on the values of males and females were verified using an unpaired Student's t‐test. All the parameters analysed were similar between sexes, with exception of AP, which was higher in females (191.43 ± 31.86 U/l). Alanine aminotransferase and uric acid values for Trichechus manatus manatus are reported for the first time in this paper. This study is the first to report serum chemistry parameter values for long‐term captive male and female Antillean manatees. Therefore, the lower values of albumin, phosphate, chloride, cholesterol and triglycerides obtained here highlight the importance of clinical pathology during health monitoring of captive marine mammals. 相似文献
10.
Ana C Mendes M Madalena Caldeira Claudia Silva Shawn C Burgess Matthew E Merritt Filipe Gomes Cristina Barosa Teresa C Delgado Fatima Franco Pedro Monteiro Luis Providencia John G Jones 《Magnetic resonance in medicine》2006,56(5):1121-1125
Menthol glucuronide was isolated from the urine of a healthy 70-kg female subject following ingestion of 400 mg of peppermint oil and 6 g of 99% [U-(13)C]glucose. Glucuronide (13)C-excess enrichment levels were 4-6% and thus provided high signal-to-noise ratios (SNRs) for confident assignment of (13)C-(13)C spin-coupled multiplet components within each (13)C resonance by (13)C NMR. The [U-(13)C]glucuronide isotopomer derived via direct pathway conversion of [U-(13)C]glucose to [U-(13)C]UDP-glucose was resolved from [1,2,3-(13)C(3)]- and [1,2-(13)C(2)]glucuronide isotopomers derived via Cori cycle or indirect pathway metabolism of [U-(13)C]glucose. In a second study, a group of four overnight-fasted patients (63 +/- 10 kg) with severe heart failure were given peppermint oil and infused with [U-(13)C]glucose for 4 hr (14 mg/kg prime, 0.12 mg/kg/min constant infusion) resulting in a steady-state plasma [U-(13)C]glucose enrichment of 4.6% +/- 0.6%. Menthol glucuronide was harvested and glucuronide (13)C-isotopomers were analyzed by (13)C NMR. [U-(13)C]glucuronide enrichment was 0.6% +/- 0.1%, and the sum of [1,2,3-(13)C(3)] and [1,2-(13)C(2)]glucuronide enrichments was 0.9% +/- 0.2%. From these data, flux of plasma glucose to hepatic UDPG was estimated to be 15% +/- 4% that of endogenous glucose production (EGP), and the Cori cycle accounted for at least 32% +/- 10% of GP. 相似文献