全文获取类型
收费全文 | 1988篇 |
免费 | 69篇 |
国内免费 | 34篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 29篇 |
妇产科学 | 69篇 |
基础医学 | 237篇 |
口腔科学 | 31篇 |
临床医学 | 128篇 |
内科学 | 351篇 |
皮肤病学 | 63篇 |
神经病学 | 263篇 |
特种医学 | 95篇 |
外科学 | 267篇 |
综合类 | 9篇 |
预防医学 | 262篇 |
眼科学 | 38篇 |
药学 | 113篇 |
中国医学 | 1篇 |
肿瘤学 | 125篇 |
出版年
2023年 | 5篇 |
2022年 | 22篇 |
2021年 | 65篇 |
2020年 | 31篇 |
2019年 | 34篇 |
2018年 | 46篇 |
2017年 | 42篇 |
2016年 | 50篇 |
2015年 | 43篇 |
2014年 | 69篇 |
2013年 | 85篇 |
2012年 | 164篇 |
2011年 | 154篇 |
2010年 | 87篇 |
2009年 | 82篇 |
2008年 | 154篇 |
2007年 | 155篇 |
2006年 | 149篇 |
2005年 | 152篇 |
2004年 | 143篇 |
2003年 | 120篇 |
2002年 | 120篇 |
2001年 | 12篇 |
2000年 | 7篇 |
1999年 | 7篇 |
1998年 | 16篇 |
1997年 | 11篇 |
1996年 | 8篇 |
1995年 | 17篇 |
1994年 | 8篇 |
1993年 | 12篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有2091条查询结果,搜索用时 15 毫秒
41.
Emma G. Wilmot PhD Kelly L. Close MBA Dubravka Jurišić-Eržen MD Daniela Bruttomesso MD F. Javier Ampudia-Blasco MD Zsolt Bosnyak MD Aude Roborel de Climens PhD Grégory Bigot MSc Anne L. Peters MD Eric Renard MD Lori Berard RN Luis Eduardo Calliari MD Jochen Seufert MD 《Diabetes, obesity & metabolism》2021,23(8):1892-1901
42.
Evidence for a lipochaperonin: Association of active proteinfolding GroESL oligomers with lipids can stabilize membranes under heat shock conditions 下载免费PDF全文
Zsolt Trk Ibolya Horvth Pierre Goloubinoff Eszter Kovcs Attila Glatz Gbor Balogh Lszl Vígh 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(6):2192-2197
During heat shock, structural changes in proteins and membranes may lead to cell death. While GroE and other chaperone proteins are involved in the prevention of stress-induced protein aggregation and in the recovery of protein structures, a mechanism for short-term membrane stabilization during stress remains to be established. We found that GroEL chaperonin can associate with model lipid membranes. Binding was apparently governed by the composition and the physical state of the host bilayer. Limited proteolysis of GroEL oligomers by proteinase K, which removes selectively the conserved glycine- and methionine-rich C terminus, leaving the chaperonin oligomer intact, prevented chaperonin association with lipid membranes. GroEL increased the lipid order in the liquid crystalline state, yet remained functional as a protein-folding chaperonin. This suggests that, during stress, chaperonins can assume the functions of assisting the folding of both soluble and membrane-associated proteins while concomitantly stabilizing lipid membranes. 相似文献
43.
Effect of inhibitors of myeloperoxidase on the development of aortic atherosclerosis in an animal model 总被引:3,自引:0,他引:3
Békési G Heinle H Kakucs R Pázmány T Szombath D Dinya M Tulassay Z Fehér J Rácz K Székács B Riss E Farkas A Gódor F Illyés G 《Experimental gerontology》2005,40(3):199-208
Our earlier studies have shown that some steroids increase myeloperoxidase enzyme (MPO) release from human granulocytes, and that MPO plasma levels are significantly lower in postclimacteric people. Moreover, we have proven that MPO inhibits production of atherogenic free radical superoxide anion and MPO-inhibitors increase superoxide release. The aim of the present study was to investigate the effect of MPO-inhibitors on the early phase of aortic atherosclerosis, namely the extent of intimal plaques and the thickening of the medial layer. Adult male rabbits were fed with lipid rich food (cholesterol: 1.3%, peanut oil: 8%) for 8 weeks. During this period MPO-inhibitors were also given (4-aminobenzoicacid-hydrazide/ABAH/-13.3 mg/kg/day or indometacin-5 mg/kg/day). All animals developed intimal lipid plaques (raised fatty streaks). The relative plaque-covered areas of the aortas were compared and the media thickness of the aorta was measured on plaque-free as well as plaque-containing areas. The medial smooth muscle density and peroxidase activity of the aortic media were also determined. The media thickness increased (p<0.05) in the cholesterol+ABAH as well as in the cholesterol+indometacin groups up to 375.7 (+/-60.5) and 442.5 (+/-123.4) microm, respectively, compared to the control group (cholesterol feeding alone) where it measured only 308.4 (+/-51.67) microm. The medial peroxidase activity decreased significantly in the indometacin treated group and showed a decreasing tendency using ABAH. In parallel to this there was a tendency of increase in the relative plaque covered areas. The smooth muscle density showed no significant modifications, while inhibitors of the MPO seemed to enhance aortic medial thickness, i.e. the grade of a pre-atherosclerotic lesion, in our animal model. Collectively, the anti-atherogenic effect of certain steroid hormones might be realized through the impact on MPO activity. 相似文献
44.
45.
Introduction
Knowledge about the functional consequences of lower limb long bone fractures is helpful to inform patients, clinicians and employers about their recovery process and prognosis. This study aims to describe the epidemiology and health outcomes of femoral and tibial shaft fractures treated at two level I trauma centres, by comparing the differences between patients with delayed union or nonunion and patients with union.Patients and methods
An analysis of registry data over two years, supplemented with medical record review, was conducted. Fracture healing was retrospectively assessed by clinical and radiological evidence of union, and the need for surgical intervention. SF-12 scores, and work and pain status were prospectively recorded at six and twelve months post injury.Results
285 fractures progressed to union and 138 fractures developed delayed union or nonunion. There was a significant difference between the two cohorts with regards to the mechanism of injury, association with multi-trauma, open fractures, grade of Gustilo classification, patient fund source, smoking status and presence of comorbidities. The SF-12 physical component score was less than 50 at both six and twelve months with improvement in the union group, but not in the delayed union or nonunion group. 72% of patients with union had returned to work at one year, but 54% continued to have pain. The difference compared to patients with delayed union or nonunion was significant.Discussion
Even patients whose fractures unite in the expectant time-frame will have residual physical disability. Patients with delayed union or nonunion have still poorer outcomes, including ongoing problems with returning to work and pain. It is important to educate patients about their injury so that they have realistic expectations. This is particularly relevant given that the patients most likely to sustain femoral or tibial shaft fractures are working-age healthy adults, and up to a third of fractures may develop delayed union or nonunion.Conclusion
Despite modern treatment, the patient-reported outcomes of lower limb long bone shaft fractures do not return to normal at one year. Patients with delayed union or nonunion can expect poorer outcomes. 相似文献46.
47.
Maximal strength,power, and aerobic endurance adaptations to concurrent strength and sprint interval training 总被引:1,自引:0,他引:1
Gregory S. Cantrell Brian K. Schilling Max R. Paquette Zsolt Murlasits 《European journal of applied physiology》2014,114(4):763-771
Purpose
This study was designed to examine whether concurrent sprint interval and strength training (CT) would result in compromised strength development when compared to strength training (ST) alone. In addition, maximal oxygen consumption (VO2max) and time to exhaustion (TTE) were measured to determine if sprint interval training (SIT) would augment aerobic performance.Methods
Fourteen recreationally active men completed the study. ST (n = 7) was performed 2 days/week and CT (n = 7) was performed 4 days/week for 12 weeks. CT was separated by 24 h to reduce the influence of acute fatigue. Body composition was analyzed pre- and post-intervention. Anaerobic power, one-repetition maximum (1RM) lower- and upper-body strength, VO2max and TTE were analyzed pre-, mid-, and post-training. Training intensity for ST was set at 85 % 1RM and SIT trained using a modified Wingate protocol, adjusted to 20 s.Results
Upper- and lower-body strength improved significantly after training (p < 0.001) with no difference between the groups (p > 0.05). VO2max increased 40.9 ± 8.4 to 42.3 ± 7.1 ml/kg/min (p < 0.05) for CT, whereas ST remained unchanged. A significant difference in VO2max (p < 0.05) was observed between groups post-intervention (CT: 42.3 ± 7.1 vs. ST: 36.0 ± 3.0 ml/kg/min). A main effect for time and group was observed in TTE (p < 0.05). A significant main effect for time was observed in average power (p < 0.05).Conclusion
Preliminary findings suggest that performing concurrent sprint interval and strength training does not attenuate the strength response when compared to ST alone, while also improves aerobic performance measures, such as VO2max at the same time. 相似文献48.
49.
Zsolt Csenki Anita Risa Dorottya Srkny Edina Garai Ildik Bata-Vidcs Erzsbet Baka Andrs Szekeres Mnika Varga Andrs cs Jeffrey Griffitts Katalin Bakos Ills Bock Istvn Szab Balzs Kriszt Bla Urbnyi Jzsef Kukolya 《Toxins》2022,14(4)
Aflatoxin B1 (AFB1) is a potent mycotoxin and natural carcinogen. The primary producers of AFB1 are Aspergillus flavus and A. parasiticus. Sterigmatocystin (STC), another mycotoxin, shares its biosynthetic pathway with aflatoxins. While there are abundant data on the biological effects of AFB1, STC is not well characterised. According to published data, AFB1 is more harmful to biological systems than STC. It has been suggested that STC is about one-tenth as potent a mutagen as AFB1 as measured by the Ames test. In this research, the biological effects of S9 rat liver homogenate-activated and non-activated STC and AFB1 were compared using two different biomonitoring systems, SOS-Chromotest and a recently developed microinjection zebrafish embryo method. When comparing the treatments, activated STC caused the highest mortality and number of DNA strand breaks across all injected volumes. Based on the E. coli SOS-Chromotest, the two toxins exerted the same genotoxicities. Moreover, according to the newly developed zebrafish microinjection method, STC appeared more toxic than AFB1. The scarce information correlating AFB1 and STC toxicity suggests that AFB1 is a more potent genotoxin than STC. Our findings contradict this assumption and illustrate the need for more complex biomonitoring systems for mycotoxin risk assessment. 相似文献
50.
László Herszényi Loránd Barabás István Hritz Gábor István Zsolt Tulassay 《World journal of gastroenterology : WJG》2014,20(37):13246-13257
Tumor invasion and metastasis is a highly complicated, multi-step phenomenon. In the complex event of tumor progression, tumor cells interact with basement membrane and extracellular matrix components. Proteolytic enzymes (proteinases) are involved in the degradation of extracellular matrix, but also in cancer invasion and metastasis. The four categories of proteinases (cysteine-, serine-, aspartic-, and metalloproteinases) are named and classified according to the essential catalytic component in their active site. We and others have shown that proteolytic enzymes play a major role not only in colorectal cancer (CRC) invasion and metastasis, but also in malignant transformation of precancerous lesions into cancer. Tissue and serum-plasma antigen concentrations of proteinases might be of great value in identifying patients with poor prognosis in CRC. Our results, in concordance with others indicate the potential tumor marker impact of proteinases for the early diagnosis of CRC. In addition, proteinases may also serve as potential target molecules for therapeutic agents. 相似文献