全文获取类型
收费全文 | 618篇 |
免费 | 35篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 23篇 |
妇产科学 | 21篇 |
基础医学 | 92篇 |
口腔科学 | 18篇 |
临床医学 | 40篇 |
内科学 | 156篇 |
皮肤病学 | 15篇 |
神经病学 | 19篇 |
特种医学 | 14篇 |
外科学 | 112篇 |
综合类 | 8篇 |
预防医学 | 39篇 |
眼科学 | 22篇 |
药学 | 34篇 |
中国医学 | 1篇 |
肿瘤学 | 39篇 |
出版年
2023年 | 5篇 |
2022年 | 6篇 |
2021年 | 17篇 |
2020年 | 10篇 |
2019年 | 7篇 |
2018年 | 18篇 |
2017年 | 8篇 |
2016年 | 7篇 |
2015年 | 17篇 |
2014年 | 35篇 |
2013年 | 26篇 |
2012年 | 49篇 |
2011年 | 79篇 |
2010年 | 32篇 |
2009年 | 23篇 |
2008年 | 46篇 |
2007年 | 61篇 |
2006年 | 41篇 |
2005年 | 31篇 |
2004年 | 21篇 |
2003年 | 25篇 |
2002年 | 27篇 |
2001年 | 1篇 |
2000年 | 5篇 |
1999年 | 2篇 |
1998年 | 4篇 |
1997年 | 3篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 4篇 |
1993年 | 6篇 |
1992年 | 6篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 4篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1976年 | 2篇 |
排序方式: 共有654条查询结果,搜索用时 15 毫秒
81.
Hettiarachchi M Liyanage C Wickremasinghe R Hilmers D Abrams S 《The Ceylon medical journal》2006,51(3):89-92
OBJECTIVE: Growth and dietary intake data are essential for formulation of nutritional policies and interventions for children. DESIGN: 945 school children (11-16 years) were subjected to growth assessment and their nutrient intake was determined using the 24-hour dietary recall method on three consecutive days. RESULTS: 21.3% of boys and 21.1% of girls were stunted (-2SD below the median height-for-age). 141 (14.9%) children were both stunted and wasted (-2 SD below the median weight-for-age). Mean body mass index of girls was significantly higher (p < 0.001) than boys at all ages. The mean daily dietary intake of energy was 3.2 (+/- 2.4) MJ, protein 29.1 (+/- 2.1) g, fat 4.5 (+/- 1.1) g, iron 11.5 (+/- 1.0) mg, and zinc 0.8 (+/- 0.7) mg among boys. Among girls, energy intake was 4.2 (+/- 1.8) MJ, protein 29.0 (+/- 2.3) g, fat 4.4 (+/- 1.0) g, iron 11.4 (+/- 1.0) mg, and zinc 0.5 (+/- 0.6) mg. Fat comprised about 4.0% of the daily energy intake. CONCLUSIONS: High rate of growth deficiency and undernutrition among adolescents mandates innovative nutritional intervention strategies. The observed mean intakes of nutrients in the sample showed a worrisome deviation from the recommendations of the dietary guidelines for Sri Lanka. 相似文献
82.
Assessing micronutrient status in children may also have the benefit of addressing the problems of various micronutrient deficiencies with a unified programmatic approach on a public health scale. A cross‐sectional survey in the Galle district of the micronutrient and anthropometric status of 248 children of ages 3–5 years was performed to determine the prevalence of micronutrient deficiencies [iron, zinc (Zn), folate, calcium, caeruloplasmin, iodine, vitamin A and vitamin D] and the extent to which multiple micronutrient deficiencies coexist. The prevalence of anaemia [haemogbolin (Hb) < 110.0 g L?1] was 34.0% in males and 33.0% in females (overall 33.5%, gender difference, P = 0.92). In anaemic children, 7.0% of males and 15.0% of females were iron deficient (serum ferritin < 15.0 µg L?1). Folate deficiency (<3.00 ng mL?1) was found in 41.0% and 33.0% of male and female, respectively, whereas Zn deficiency (<9.95 µmol L?1) occurred in 57.0% and 50.0% of male and female, respectively. Serum vitamin D deficiency (<35.0 nmol L?1) was found in 26% and 25% of male and female, respectively. Anaemic males had a 3.0‐fold (95% confidence interval (CI) 1.1–8.3) and 2.3‐fold (95% CI 0.8–6.6) greater risk of being underweight and thin, whereas the risk among anaemic females was 0.7‐fold (95% CI 0.3–1.8) and 0.9‐fold (95% CI 0.3–2.6) for being underweight and thin. Only 7.3% of the subjects did not have any micronutrient deficiency, 38.3% were deficient in two micronutrients, 17.7% had three micronutrient deficiencies and 6.0% had four or more micronutrient deficiencies. Multiple micronutrient deficiencies are prevalent in Sri Lankan pre‐school children and established baseline data for future studies. 相似文献
83.
84.
Background
Whole blood donation is generally considered to be a safe procedure, but occasionally adverse reactions of varying severity may occur during or at the end of the collection. The aim of the study was to estimate the frequency and type of adverse events occurring during blood donation and to assess the practices which would help to minimise them.Materials and methods
This retrospective single-centre study was conducted from June 2007 to November 2009 at a regional blood transfusion centre. All whole blood donations made at the centre were analysed. All adverse events occurring during or at the end of donation were noted using a standardised format.Results
Overall 113 adverse events were reported in relation to 19,045 donations, resulting in an overall adverse event rate of 0.6%, that is, an incidence of 1 in every 166 donations. Presyncopal symptoms, in other words vasovagal reactions of mild intensity, were the most commonly observed adverse reactions and accounted for approximately 70% of all adverse reactions noted.Conclusions
Only 0.6% of blood donations were complicated by adverse events and most of these events were presyncopal symptoms. Our study reinforces the fact that blood donation is a very safe procedure which could be made even more event-free by following certain friendly, reassuring and tactful practices. 相似文献85.
86.
87.
88.
Selim S Sunkara M Salous AK Leung SW Berdyshev EV Bailey A Campbell CL Charnigo R Morris AJ Smyth SS 《Clinical science (London, England : 1979)》2011,121(12):565-572
Anaemia and RBC (red blood cell) transfusion may be associated with worse clinical outcomes, especially with longer blood storage duration prior to transfusion. The mechanisms underlying these harmful effects are unknown. RBCs have been proposed to buffer plasma S1P (sphingosine 1-phosphate), a lysophospholipid essential for the maintenance of endothelial integrity and important in the regulation of haematopoietic cell trafficking. The present study examined the effect of anaemia, RBC transfusion and RBC storage duration on plasma S1P levels. Plasma S1P from 30 individuals demonstrated a linear correlation with Hct (haematocrit; R2 = 0.51, P < 0.001) with no evidence for a plateau at Hct values as low as 19%. RBC transfusion in 23 anaemic patients with baseline mean Hct of 22.2 ± 0.34% (value is the mean ± S.D.) increased Hct to 28.3 ± 0.6% at 72 h. Despite an Hct increase, RBC transfusion failed to elevate plasma S1P consistently. A trend towards an inverse correlation was observed between RBC storage duration and the post-transfusion increase in plasma S1P. After 30 days of storage, RBC S1P decreased to 19% of that observed in fresh (3-7-day-old) RBC segments. RBC membranes contain low levels of both S1P phosphatase and S1P lyase activities that may account for the decline in S1P levels with storage. Our results support a role for RBCs in buffering plasma S1P and identify a disturbance in the capacity after transfusion. Changes in S1P content may contribute to an RBC storage lesion. Further studies should investigate the clinical significance of alterations in circulating S1P levels and the potential value of enriching stored RBCs with S1P. 相似文献
89.
Evaluation of the diagnostic efficacy of PCR for Ureaplasma urealyticum infection in Indian adults with symptoms of genital discharge 总被引:3,自引:0,他引:3
Dhawan B Gupta V Khanna N Singh M Chaudhry R 《Japanese journal of infectious diseases》2006,59(1):57-58
Ureaplasma urealyticum genital infection may lead to severe clinical implications if left undiagnosed and untreated. The present study was conducted to evaluate the diagnostic efficiency of a polymerase chain reaction (PCR) assay and to determine the prevalence of U. urealyticum in Indian adults with symptoms of genital discharge. Cervical swabs, vaginal swabs and male urethral swabs from 100 patients attending an sexually transmitted disease clinic at a tertiary care hospital in Delhi were screened prospectively for infection with U. urealyticum. The prevalence of U. urealyticum was found to be 32% by culture and 45% by PCR. U. urealyticum was recovered from 8 (47%) and 37 (45%) symptomatic men and women, respectively. The agreement between PCR and culture was 93.75%. PCR improved the test sensitivity by 13% compared to culture. The results confirm the need to use a sensitive and reliable molecular method to prevent the underdiagnosis of ureaplasma infection and to facilitate better clinical management of this infection in India. 相似文献
90.
Gowrishankar M Kamel KS Halperin ML 《Journal of the American Society of Nephrology : JASN》2007,18(8):2278-2280
In the traditional approach to buffering of H(+) during metabolic acidosis, the sole focus is on lowering the H(+) concentration, but this overlooks several important points. First, increased binding of H(+) to proteins changes their charge, shape, and possibly function. Second, organs in which buffering of H(+) occurs is not assessed even though it would be advantageous to spare brain proteins in this process. Third, only the arterial and not the capillary PCO(2) of individual organs is considered. This article provides a "brain protein-centered" view, which leads to different conclusions concerning the way H(+) are removed physiologically. 相似文献