全文获取类型
收费全文 | 29860篇 |
免费 | 2368篇 |
国内免费 | 53篇 |
专业分类
耳鼻咽喉 | 281篇 |
儿科学 | 1006篇 |
妇产科学 | 766篇 |
基础医学 | 4021篇 |
口腔科学 | 404篇 |
临床医学 | 4114篇 |
内科学 | 5549篇 |
皮肤病学 | 411篇 |
神经病学 | 2787篇 |
特种医学 | 730篇 |
外科学 | 3453篇 |
综合类 | 379篇 |
一般理论 | 53篇 |
预防医学 | 3650篇 |
眼科学 | 419篇 |
药学 | 1932篇 |
1篇 | |
中国医学 | 47篇 |
肿瘤学 | 2278篇 |
出版年
2023年 | 298篇 |
2022年 | 420篇 |
2021年 | 962篇 |
2020年 | 616篇 |
2019年 | 959篇 |
2018年 | 1051篇 |
2017年 | 766篇 |
2016年 | 798篇 |
2015年 | 900篇 |
2014年 | 1170篇 |
2013年 | 1624篇 |
2012年 | 2335篇 |
2011年 | 2340篇 |
2010年 | 1267篇 |
2009年 | 1049篇 |
2008年 | 1793篇 |
2007年 | 1897篇 |
2006年 | 1715篇 |
2005年 | 1641篇 |
2004年 | 1462篇 |
2003年 | 1275篇 |
2002年 | 1182篇 |
2001年 | 369篇 |
2000年 | 325篇 |
1999年 | 276篇 |
1998年 | 250篇 |
1997年 | 195篇 |
1996年 | 175篇 |
1995年 | 119篇 |
1994年 | 113篇 |
1993年 | 128篇 |
1992年 | 178篇 |
1991年 | 183篇 |
1990年 | 164篇 |
1989年 | 173篇 |
1988年 | 161篇 |
1987年 | 205篇 |
1986年 | 158篇 |
1985年 | 156篇 |
1984年 | 133篇 |
1983年 | 111篇 |
1981年 | 63篇 |
1980年 | 61篇 |
1979年 | 76篇 |
1978年 | 74篇 |
1976年 | 63篇 |
1974年 | 73篇 |
1973年 | 80篇 |
1972年 | 66篇 |
1971年 | 66篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Optimal timing of a single dose of zoledronic acid to increase strength in rat fracture repair. 总被引:4,自引:0,他引:4
Negin Amanat Michelle McDonald Craig Godfrey Lynne Bilston David Little 《Journal of bone and mineral research》2007,22(6):867-876
We hypothesized that ZA treatment would bolster fracture repair. In a rat model for closed fracture healing, a single dose of ZA at 0, 1, or 2 wk after fracture significantly increased BMC and strength of the healed fracture. Delaying the dose (1 or 2 wk after fracture) displayed superior results compared with dosing at the time of fracture. INTRODUCTION: Bisphosphonates are known to increase bone strength and thus the resistance to fracture by decreasing osteoclastic bone resorption. These properties may enable bisphosphonates to also increase the strength of fracture repair. Zoledronic acid (ZA) is a potent bisphosphonate with a high affinity for bone mineral, allowing bolus intravenous dosing in a range of indications. In this study, we examined the application of bolus dose ZA in endochondral fracture repair. MATERIALS AND METHODS: Carbon-14 labeled ZA was used in a closed rat fracture model. Rats were divided into five treatment groups (n = 25 per group): saline control, local ZA (0.01 mg/kg), and three systemic bolus ZA groups (0.1 mg/kg) with different administration times: at fracture, 1 wk after fracture, and 2 wk after fracture. Rats were killed 6 wk postoperatively. Postmortem analyses included radiography, QCT, microCT, biomechanical testing, scintillation counting, autoradiography, and histology. RESULTS: Single-dose systemic ZA administration significantly increased callus volume, callus BMC, and mechanical strength. Perioperative treatment increased mechanical strength by 30% compared with controls (p < 0.05). Administering the systemic dose at 1 or 2 wk after fracture further increased mechanical strength compared with controls by 44% and 50%, respectively (p < 0.05). No significant differences in mechanical parameters were seen with local injection at the dose studied. Autoradiographic analysis indicated that ZA binds significantly to bone that is present at the time of administration. ZA quantification indicated that delayed administration significantly increased the uptake efficiency in the callus. Histological and microCT analysis showed that ZA treated calluses had a distinctive internal structure consisting of an intricate network of retained trabecular bone. CONCLUSIONS: The timing of a single systemic dose of ZA plays an important role in the modulation of callus properties in this rat fracture model; delaying the single dose produces a larger and stronger callus. 相似文献
52.
Mario Sénéchal Isabelle Lemieux Isabel Beucler Gerard Drobinski Sylvie Cormont Michelle Dubois Iradj Gandjbakhch Jean-Pierre Després Richard Dorent 《The Journal of heart and lung transplantation》2005,24(7):819-826
BACKGROUND: This study evaluated the prevalence of the atherogenic metabolic triad and the hypothesis that waist circumference and fasting triglyceride concentrations could be used as screening tools for identification of the atherogenic metabolic triad in a population of heart transplant men. It also evaluated the relationship between the atherogenic metabolic triad and coronary artery disease (CAD). METHODS: In the study group of 83 consecutive male heart transplant patients having their routine annual coronarography, 23 patients (28%) were characterized by the atherogenic metabolic triad defined by the presence of elevated fasting insulin and apolipoprotein B concentrations and by small low-density lipoprotein (LDL) particles. RESULTS: Seventy-seven per cent of patients with waist circumference values >/= 90 cm and with elevated triglyceride levels (>/=2.0 mmol/liter) were characterized by this atherogenic metabolic triad. Patients with the atherogenic metabolic triad were at markedly increased risk of CAD (odds ratio of 25.3, 95% CI: 1.11-577.3, p < 0.04) compared to heart transplant patients without the atherogenic metabolic triad. CONCLUSIONS: About 30% of heart transplant patients showed the features of the atherogenic metabolic triad. Measurement and interpretation of waist circumference and fasting triglycerides could be used among heart transplant patients to early identify men characterized by the presence of elevated fasting insulin and apolipoprotein B concentrations and small LDL particles. The presence of the atherogenic metabolic triad identified patients at high risk of CAD even in the heart transplant population. 相似文献
53.
OBJECTIVE: This study investigated non-adherence to antiepileptic drug treatment amongst patients with epilepsy in secondary care. The associations between adherence and seizure control, perceptions of illness and medication, anxiety and depression were also examined. METHODS: A cross-sectional study of fifty-four patients with epilepsy were recruited from a hospital epilepsy clinic. RESULTS: Fifty-nine percent were estimated to be non-adherent to medication. There was a negative correlation between adherence and frequency of seizures. Patients with poorly controlled epilepsy were more anxious, and expected a longer duration of their epilepsy. CONCLUSION: Assessment of adherence should be a routine part of management of epilepsy. Further recognition and support should be given to patients who have poor seizure control since they are more likely to be more anxious and have unhelpful illness and treatment beliefs. 相似文献
54.
55.
56.
Barry J. Cusack Stephan P. Young Vicki L. Loseke Michelle R. Hurty Loring Beals Richard D. Olson 《Cancer chemotherapy and pharmacology》1992,30(2):145-148
Summary Malnutrition involving protein deficiency, which commonly occurs in cancer patients receiving anthracycline treatment, is considered to be a risk factor for the development of cardiotoxicity. Protein deficiency has been shown to impair the metabolism of drugs such as theophylline and acetaminophen. If protein deficiency also impairs anthracycline metabolism, it could explain at least in part the enchanced anthracycline toxicity associated with malnutrition. We tested this idea by determining the effect of a low- protein, isocaloric diet on doxorubicin pharmacokinetics in rabbits. The animals were randomized into two groups for 8–12 weeks. Rabbits in group 1 received a low-protein (5%), isocaloric diet, whereas those in group 2 received a normal-protein (15%) diet. Both groups (group 1,n=15; group 2,n=14) were given 5 mg/kg doxorubicin by i.v. bolus. After doxorubicin injection, blood samples were obtained over the next 52 h for the measurement of doxorubicin and doxorubicinol plasma concentrations by high-performance liquid chromatography (HPLC) with fluorometric detection. The low-protein diet significantly decreased doxorubicin clearance (48±3 vs 59±4 ml min–1 kg–1;P<0.05), prolonged the terminal climination half-life (28±2 vs 22±2 h;P<0.05), and increased the area under the plasma concentration/time curve extrapolated to infinity (1722±122 vs 1405±71 ng h ml–1;P<0.05) as compared with the values determined for rabbits fed the standard rabbit chow (15% protein). The volume of distribution for doxorubicin was not altered by the low-protein diet. In addition, in rabbits fed the the low-portein diet, the terminal elimination half-life of the alcohol metabolite, doxorubicinol was prolonged (52±5 vs 40±2 h;P<0.05). Thus, a low-protein diet causes a reduction in the ability of rabbits to eliminate doxorubicin and possibly its alcohol metabolite doxorubicinol. If a similar alteration in anthracycline pharmacokinetics occurs in malnourished cancer patients, this phenomenon may contribute to their increased risk of developing cardiotoxicity associated with anthracycline therapy.Supported by the Department of Veterans Affairs and the American Heart Foundation 相似文献
57.
58.
Neurological disease associated with Mycoplasma pneumoniae infection. PCR evidence against a direct invasive mechanism
下载免费PDF全文
![点击此处可从《Journal of clinical pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Aims—To investigate the pathology in patients presenting with sudden onset neurological illnesses associated with Mycoplasma pneumoniae infection. 相似文献
59.
60.