全文获取类型
收费全文 | 3692篇 |
免费 | 335篇 |
国内免费 | 44篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 54篇 |
妇产科学 | 80篇 |
基础医学 | 209篇 |
口腔科学 | 112篇 |
临床医学 | 516篇 |
内科学 | 448篇 |
皮肤病学 | 19篇 |
神经病学 | 110篇 |
特种医学 | 57篇 |
外科学 | 361篇 |
综合类 | 494篇 |
预防医学 | 750篇 |
眼科学 | 17篇 |
药学 | 389篇 |
20篇 | |
中国医学 | 158篇 |
肿瘤学 | 264篇 |
出版年
2024年 | 21篇 |
2023年 | 79篇 |
2022年 | 168篇 |
2021年 | 212篇 |
2020年 | 229篇 |
2019年 | 156篇 |
2018年 | 152篇 |
2017年 | 148篇 |
2016年 | 152篇 |
2015年 | 132篇 |
2014年 | 251篇 |
2013年 | 274篇 |
2012年 | 221篇 |
2011年 | 247篇 |
2010年 | 186篇 |
2009年 | 182篇 |
2008年 | 131篇 |
2007年 | 145篇 |
2006年 | 117篇 |
2005年 | 104篇 |
2004年 | 100篇 |
2003年 | 74篇 |
2002年 | 60篇 |
2001年 | 63篇 |
2000年 | 58篇 |
1999年 | 45篇 |
1998年 | 38篇 |
1997年 | 29篇 |
1996年 | 37篇 |
1995年 | 37篇 |
1994年 | 27篇 |
1993年 | 20篇 |
1992年 | 10篇 |
1991年 | 17篇 |
1990年 | 15篇 |
1989年 | 10篇 |
1988年 | 4篇 |
1987年 | 6篇 |
1986年 | 8篇 |
1985年 | 16篇 |
1984年 | 10篇 |
1983年 | 9篇 |
1982年 | 16篇 |
1981年 | 17篇 |
1979年 | 7篇 |
1977年 | 3篇 |
1976年 | 6篇 |
1975年 | 4篇 |
1974年 | 4篇 |
1973年 | 3篇 |
排序方式: 共有4071条查询结果,搜索用时 9 毫秒
11.
Douglas W. Scott 《Journal of human nutrition and dietetics》1988,1(1):59-70
A system of data collection and analysis based on patient visits was evaluated over a four-week period in five districts and a six-month period in one district by twenty-five dietitians. Each patient visit was analysed by diagnosis (the problem), by diet (the treatment) and by nutritional care level (the action). The system was seen to encourage self analysis by dietitians and proved a useful educational tool in addition to providing dietetic managers with data on clinical dietetic activity. It was considered successful and well accepted in four of the six districts. 相似文献
12.
13.
VRML metabolic network visualizer 总被引:1,自引:0,他引:1
Rojdestvenski I 《Computers in biology and medicine》2003,33(2):169-182
14.
Marco Caldin Tommaso Furlanello Laia Solano-Gallego Davide De Lorenzi Erika Carli Silvia Tasca George Lubas 《Comparative clinical pathology》2005,14(1):5-12
Donkeys, an endangered species, have recently gained a new application with the use of their milk to feed humans with allergic processes. The Ragusana donkey breed from Sicily is used to produce milk for humans with allergic diseases. In order to evaluate the hygienic, nutritional and management measures on a farm of Ragusana donkeys, complete blood counts, extended biochemical profiles and serum protein electrophoresis, as part of metabolic profile test (MPT), were performed in Ragusana donkeys. Fifty-four donkeys were studied and grouped according to their age, (1) 29 females and a single stallion (n=30), (2) young females, 1 – 3 years old (n=10) and (3) young of both sexes under 1 year old (n=14). The RBC count, RDW value, Lymp, and Mono counts, and PDW values were statistically greater in donkeys under one year old than in adult donkeys, while the Seg Neu count was lower. The CPK, ALP, iPhos, and HCO3, values were statistically higher in the group of donkeys under 1 year of age than adult donkeys while Cl and LDH values were statistically lower in donkeys under 1 year than adult donkeys. Additionally, statistically significant increased values for CPK, ALP, Alb, Chol, iPhos, HCO3, and UIBC in young donkeys under 1 year when compared with young donkeys, 1 – 3 years were observed. A statistically significant decreased value for Urea and an increased value for Crea in young donkeys, 1 – 3 years old were found as compared to adults. The serum protein fractions recognised by electrophoresis were: albumin, alpha globulin (subdivided into alpha-1 and alpha-2-globulins), beta globulin, and gamma globulin. In the alpha-1-globulin region three small peaks were constantly noticed, and alpha-2-globulins were statistically different between the three groups being greater in young donkeys under 1 year of age. The results obtained were used both to establish reference ranges and a data bank for the farm of Ragusana donkeys for future needs in assessing the metabolic status and health of the animals. 相似文献
15.
C. Goodman G. G. Rogers H. Vermaak M. R. Goodman 《European journal of applied physiology》1985,54(4):436-441
Summary We set out to demonstrate whether changes in plasma volume, haematocrit and some important blood constituents occurred after
swimming 100 m and 800 m, as well as monitoring the duration of these changes.
We measured exercise-induced changes in concentration of plasma constituents in eight subjects, and determined the expected
effects of haemoconcentration on these constituents. We also investigated the different biochemical responses occurring after
maximal exercise (100 m), as compared to submaximal exercise (800 m).
The haematocrit increased significantly after the 100 m swim and to a lesser extent after the 800-m swim, returning to basal
levels within 30 min. The plasma volume decreased by 16% on completion of the 100 m and by 8% on completion of the 800 m.
The blood lactate concentration increased 15-fold and 10-fold after the 100-m and 800-m swims respectively. The plasma potassium
concentration increased significantly immediately on completion of the 100-m swim, then decreased significantly at 2 1/2 and
5 min post-exercise, returning to near-basal values at 30 min. The potassium concentration measured after the 800-m event
did not differ significantly from basal levels, however the measured concentrations were significantly lower than the concentrations
expected on the basis of haemoconcentration. The plasma sodium concentrations measured after both 100-m and 800-m swims were
significantly increased. However, calculations correcting for haemoconcentration showed significant losses in toal circulating
sodium.
Our study demonstrates marked changes in plasma volume and certain blood constituents after maximal intensity swimming, and
less marked changes after submaximal exercise. We also demonstrated the importance of taking the effects of haemoconcentration
into account when evaluating changes in concentration of plasma constituents. 相似文献
16.
Markers of cartilage degradation hold a great, but so far underutilized potential in the research and clinical management of joint diseases such as osteoarthritis (OA) and rheumatoid arthritis (RA). With the rapid pace of development of such markers, they are likely to emerge as promising clinical tools for several uses. These roles may include: improving preclinical and clinical development in arthritis research; differentiation of patients with high and low turnover states at disease diagnosis; selection of optimal therapy and therapy dose for the individual patient; monitoring disease progression; and predicting disease outcome.This review focuses on the cartilage matrix components and the metabolites from this very special tissue that have been proposed as biochemical markers. Special attention is focused on the challenges facing the development of such markers to the standards required for widespread practical use. Examples are provided on the current use of cartilage derived biochemical markers and perspectives for the future use of markers and required clinical documentation are presented. 相似文献
17.
中药中金属元素的生化作用机理 总被引:3,自引:0,他引:3
机体内环境是一个多层次纵横交错的大系统 ,有一套复杂的调控体系 ,金属元素与此调控体系有密切联系。机体内所有复杂的生化反应都离不开酶 ,而金属元素有的是酶的辅助因子参与酶的组成 ,有的是酶的激活剂 ,是酶活性的主要调节者。深入研究中药中金属元素对酶活性的影响 ,将有利于提高药效。此外肾虚病人血清中金属元素与正常人相比有显著差异 ,若能比较准确地测得肾虚不同阶段的金属元素图谱 ,并结合中药中各金属元素含量的不同加以针对性地治疗 ,将对提高药物对疾病的治疗效果及延缓衰老有重要意义。 相似文献
18.
While quality measures are integral to the maintenance of a high standard of patient care, high-quality care remains a complicated concept to define in the context of acute care. In this article we explore how quality can be measured in the intensive care unit. Standard outcome metrics such as mortality are tangible comparators, but do not offer a comprehensive assessment of quality for the complex heterogeneity of the intensive care population. We explore the Donabedian model as a means to describe the importance of outcomes, processes, structure and environment to inform the measurement of quality. These concepts can be more abstract and difficult to measure but can provide significant insight into the culture of a unit and the resulting performance, and thus provide a more comprehensive measure of quality. 相似文献
19.
Xiurong Kang Qinghu Wang Suriguga Ao Moxiyele Wenlin Bao Chaoliang zhao a 《中草药(英文版)》2023,15(2):337-342
Objective: To establish a high-performance liquid chromatographic method (HPLC) for the simultaneous determination of sixteen compounds from Artemisia ordosica.
Methods: HPLC was used to analyze 16 quality indicators of A. ordosica. The HPLC conditions were as follows: Agilent Eclipse Plus C18 column (250 mm × 4.6 mm, 5 μm) with acetonitrile (A)-water (B) as mobile phase, gradient elution: 0?10 min, 75%?65% B; 10?30 min, 65%?35 % B; and finally 30?40 min, 35%?15% B. The flow rate was 1.0 mL/min, the column temperature was 40 °C, the injection volume was 10 μL, and monitored by absorbance at 285 nm for compounds 1?10, 12 and 225 nm for compounds 11, 13?16.
Results: Under the selected experimental chromatographic conditions, compounds 1?16 showed good linearity (r > 0.9993) in a wide concentration range. Their average recoveries were 99.50%, 95.38%, 97.75%, 96.00%, 98.20%, 97.50%, 95.50%, 99.33%, 96.75%, 96.50%, 98.50%, 97.83%, 99.20%, 95.33%, 97.33% and 96.30%, respectively, and the RSD were 1.99%, 1.81%, 1.63%, 1.98%, 1.67%, 1.92%, 1.74%, 1.67%, 1.90%, 1.72%, 1.88%, 1.83%, 1.79%, 1.76%, 1.81% and 1.96%, respectively.
Conclusion: Based on the results of the HPLC analysis, it was concluded that p-hydroxycinnamic acid (1), O-hydroxycinnamic acid (2), coniferyl alcohol (5), 5,4''-dihydroxy-7,3''-dimethoxyflavanone (8), 5,4''-dihydroxy-7-methoxyflavanone (9), 5-hydroxy-7,4''-dimethoxyflavanone (12), dehydrofalcarindiol (13), arteordoyn A (14), dehydrofalcarinol (15) and capillarin (16) are best suited for the role of quality indicators of A. ordosica grown in different ecological environments. 相似文献
20.
Gastric cancer etiology: a biochemical hypothesis. 总被引:1,自引:0,他引:1
We have proposed a two-stage biochemical model for the etiology of "intestinal" gastric cancer. The model postulates that the gastric mucosal barrier is biochemically pierced as a result of chemical interactions between the mucoproteins and mucopolysaccharides of the barrier and ingested polysaccharrides (starches). This would allow the growth of gastric flora which could produce carcinogenic nitrosamines and/or nitrosamides. Observational and experimental evidence in favor of the model is provided. The model suggests various research initiatives, the results of which might provide the basis for biochemical and physiological methods for the prevention and/or treatment of gastric cancer. Various ways in which the model may be tested are also noted. 相似文献