全文获取类型
收费全文 | 475篇 |
免费 | 34篇 |
国内免费 | 6篇 |
专业分类
儿科学 | 39篇 |
妇产科学 | 4篇 |
基础医学 | 48篇 |
口腔科学 | 7篇 |
临床医学 | 40篇 |
内科学 | 106篇 |
皮肤病学 | 5篇 |
神经病学 | 9篇 |
特种医学 | 85篇 |
外科学 | 48篇 |
综合类 | 10篇 |
预防医学 | 34篇 |
眼科学 | 14篇 |
药学 | 45篇 |
肿瘤学 | 21篇 |
出版年
2024年 | 1篇 |
2022年 | 1篇 |
2021年 | 5篇 |
2020年 | 1篇 |
2019年 | 4篇 |
2018年 | 8篇 |
2017年 | 5篇 |
2016年 | 7篇 |
2015年 | 10篇 |
2014年 | 5篇 |
2013年 | 18篇 |
2012年 | 8篇 |
2011年 | 8篇 |
2010年 | 16篇 |
2009年 | 17篇 |
2008年 | 12篇 |
2007年 | 13篇 |
2006年 | 14篇 |
2005年 | 14篇 |
2004年 | 5篇 |
2003年 | 6篇 |
2002年 | 9篇 |
2001年 | 8篇 |
2000年 | 4篇 |
1999年 | 15篇 |
1998年 | 26篇 |
1997年 | 28篇 |
1996年 | 30篇 |
1995年 | 22篇 |
1994年 | 25篇 |
1993年 | 19篇 |
1992年 | 9篇 |
1991年 | 8篇 |
1990年 | 13篇 |
1989年 | 11篇 |
1988年 | 8篇 |
1987年 | 11篇 |
1986年 | 11篇 |
1985年 | 8篇 |
1984年 | 7篇 |
1983年 | 6篇 |
1982年 | 5篇 |
1981年 | 11篇 |
1980年 | 11篇 |
1979年 | 6篇 |
1978年 | 4篇 |
1977年 | 6篇 |
1976年 | 12篇 |
1975年 | 4篇 |
排序方式: 共有515条查询结果,搜索用时 9 毫秒
91.
92.
Patrice A. Hubert Megan Mahoney Tania B. Huedo-Medina Tricia M. Leahey Valerie B. Duffy 《Nutrients》2021,13(10)
Improving our understanding of what physical activities are enjoyed and the factors that are associated with physical activity liking can promote participation in regular physical activity. We aimed to study physical activity (PA) liking in college women by modelling interactions between body size perception and dietary behaviors on PA liking, and by examining discrepancies between PA liking versus engagement on body size perception and dietary behaviors. Women (n = 251; 74% white) utilized an online survey to report their level of liking for PA types (scored into a PA liking index) and frequency of PA participation. They also reported their perceived body size, level of dietary restraint, and frequency of consuming foods (scored into a diet quality index). In multivariate analyses, a greater perceived body size was directly associated with lower PA liking and indirectly through greater dietary restraint but lower diet quality. Healthiest dietary behaviors were reported by women who both liked and engaged in PA. Women who reported high PA liking but low PA participation reported a higher dietary restraint and lower diet quality. These findings support the empowerment of women across all body sizes to identify physical activities that they enjoy. Health promotion efforts should encourage women to couple physical activity liking and engagement with a healthy level of dietary restraint and consumption of a healthy diet. 相似文献
93.
94.
95.
SJ Mundell A-L Matharu S Nisar TM Palmer JL Benovic E Kelly 《British journal of pharmacology》2010,159(3):518-533
Background and purpose:
We have investigated the effect of deletions of a postsynaptic density, disc large and zo-1 protein (PDZ) motif at the end of the COOH-terminus of the rat A2B adenosine receptor on intracellular trafficking following long-term exposure to the agonist 5′-(N-ethylcarboxamido)-adenosine.Experimental approach:
The trafficking of the wild type A2B adenosine receptor and deletion mutants expressed in Chinese hamster ovary cells was studied using an enzyme-linked immunosorbent assay in combination with immunofluorescence microscopy.Key results:
The wild type A2B adenosine receptor and deletion mutants were all extensively internalized following prolonged treatment with NECA. The intracellular compartment through which the Gln325-stop receptor mutant, which lacks the Type II PDZ motif found in the wild type receptor initially trafficked was not the same as the wild type receptor. Expression of dominant negative mutants of arrestin-2, dynamin or Eps-15 inhibited internalization of wild type and Leu330-stop receptors, whereas only dominant negative mutant dynamin inhibited agonist-induced internalization of Gln325-stop, Ser326-stop and Phe328-stop receptors. Following internalization, the wild type A2B adenosine receptor recycled rapidly to the cell surface, whereas the Gln325-stop receptor did not recycle.Conclusions and implications:
Deletion of the COOH-terminus of the A2B adenosine receptor beyond Leu330 switches internalization from an arrestin- and clathrin-dependent pathway to one that is dynamin dependent but arrestin and clathrin independent. The presence of a Type II PDZ motif appears to be essential for arrestin- and clathrin-dependent internalization, as well as recycling of the A2B adenosine receptor following prolonged agonist addition. 相似文献96.
97.
98.
The regulation of hemopoiesis in long-term bone marrow cultures. II. Stimulation and inhibition of stem cell proliferation 总被引:6,自引:1,他引:6
The isolation of a DNA synthesis inhibitor (NBME fraction IV) and stimulator (RBME fraction III) specific for the hemopoietic stem cell (CFU-s) from freshly isolated normal adult and regenerating murine bone marrow, respectively, has been well documented. We have utilized long- term liquid bone marrow cultures in a further analysis of the role of these factors in the regulation of CFU-s proliferation. Our results show that shortly after feeding, at a time when the cultured CFU-s are actively proliferating, high levels of the hemopoietic stem cell proliferation stimulator fraction III can be isolated from the culture medium. In contrast, the presence of essentially noncycling CFU-s found in cultures fed 8-10 days previously correlates with high levels of the hemopoietic stem cell inhibitor fraction IV. These results suggest that a certain balance between these factors determines CFU-s proliferation in the long-term cultures. In support of this, DNA synthesis in actively cycling CFU-s in the long-term cultures is inhibited for at least 3 days by the addition of excess NBME fraction IV (inhibitor). Furthermore, DNA synthesis in noncycling cultured CFU-s is stimulated for at least 5 days by the addition of RBME fraction III (stimulator). 相似文献
99.
R Wanitphakdeedecha TH Nguyen TM Chen 《Journal of the European Academy of Dermatology and Venereology》2010,24(4):445-448
Background Appropriate pricing for medical services of not‐for‐profit hospital is necessary. The prices should be fair to the public and should be high enough to cover the operative costs of the organization. Objective The purpose of this study was to determine the cost and unit cost of medical services performed at the Mohs and Dermasurgery Unit (MDU), Department of Dermatology, The University of Texas – MD Anderson Cancer Center, Houston, TX from the healthcare provider’s perspective. Methods MDU costs were retrieved from the Financial Department for fiscal year 2006. The patients’ statistics were acquired from medical records for the same period. Unit cost calculation was based on the official method of hospital accounting. Results The overall unit cost for each patient visit was $673.99 United States dollar (USD). The detailed unit cost of nurse visit, new patient visit, follow‐up visit, consultation, Mohs and non‐Mohs procedure were, respectively, $368.27, $580.09, $477.82, $585.52, $1,086.12 and $858.23 USD. With respect to a Mohs visit, the unit cost per lesion and unit cost per stage were $867.89 and $242.30 USD respectively. Conclusions Results from this retrospective study provide information that may be used for pricing strategy and resource allocation by the administrative board of MDU. 相似文献
100.
Justin van Loon Daniël Hoornenborg Harm M van der Vis Inger N Sierevelt Kim TM Opdam Gino MMJ Kerkhoffs Daniël Haverkamp 《World journal of orthopedics》2021,12(1):14
BACKGROUNDIn press-fit total hip arthroplasty (THA) ceramic-on-ceramic (CoC) bearings are a potential for overcoming the wear that is seen in ceramic-on-polyethylene (CoPE) bearings, and can lead to wear-induced osteolysis, resulting in loosening of the implant. However, CoC bearings show disadvantages as well, such as squeaking sounds and being more fragile, which can cause ceramic head or liner fracture. Because comparative long-term studies are limited, the objective of this study was to determine the long-term difference in wear, identify potential predictive factors for wear, investigate radiological findings such as osteolysis, and evaluate clinical functioning and complications between these bearings.AIMTo determine 10-year differences in wear, predictive factors for wear, and investigate radiological findings and clinical functioning between CoC and CoPE.METHODSThis observational prospective single-center cohort study with a 10-year follow-up includes a documented series of elective THAs. Primary outcome was wear measured by anteroposterior (AP) radiographs. Secondary outcomes were potential predictive factors for wear, complications during follow-up, Harris hip score (HHS), and radiological findings such as presence of radiolucency, osteolysis, atrophy, and hypertrophy around the cup. Due to the absence of wear in the CoC group, stratified analysis to identify risk factors for wear was only performed in the CoPE group by use of univariate linear regression analysis. HHS was expressed as a change from baseline and the association with bearing type was assessed by use of multivariate linear regression analysis, adjusted for potential confounders.RESULTSA total of 17 CoPE (63.0%) and 25 CoC (73.5%) cases were available for follow-up and showed a linear wear of respectively 0.130 mm/year (range 0.010; 0.350) and 0.000 mm/year (range 0.000; 0.005), which was significant (P < 0.001) between both groups. Wear always occurred in the cranial direction. Cup inclination was the only predictive factor for polyethylene (PE) wear. No dislocations, ceramic head, or liner fractures were seen. The HHS showed a mean change from baseline of 37.1 points (SD 18.5) in the CoPE group and 43.9 (SD 17.0) in the CoC group. This crude difference of 6.8 (range -5.2; 18.7) in favor of the CoC group was not significant (P = 0.26) and was not significant when adjusted for age, gender, and diagnosis either (P = 0.99). No significant differences in complications and radiological findings were seen between groups. CONCLUSIONCoC bearing shows lower wear rates compared to CoPE at 10-year follow-up with cup inclination as a predictive factor for wear and no differences in complications, HHS, and radiological findings. 相似文献