全文获取类型
收费全文 | 21475篇 |
免费 | 1429篇 |
国内免费 | 83篇 |
专业分类
耳鼻咽喉 | 269篇 |
儿科学 | 670篇 |
妇产科学 | 478篇 |
基础医学 | 3142篇 |
口腔科学 | 988篇 |
临床医学 | 2346篇 |
内科学 | 4241篇 |
皮肤病学 | 545篇 |
神经病学 | 1967篇 |
特种医学 | 413篇 |
外科学 | 2156篇 |
综合类 | 144篇 |
一般理论 | 10篇 |
预防医学 | 2443篇 |
眼科学 | 359篇 |
药学 | 1382篇 |
中国医学 | 89篇 |
肿瘤学 | 1345篇 |
出版年
2023年 | 200篇 |
2022年 | 330篇 |
2021年 | 813篇 |
2020年 | 475篇 |
2019年 | 731篇 |
2018年 | 791篇 |
2017年 | 564篇 |
2016年 | 562篇 |
2015年 | 682篇 |
2014年 | 905篇 |
2013年 | 1114篇 |
2012年 | 1727篇 |
2011年 | 1848篇 |
2010年 | 906篇 |
2009年 | 811篇 |
2008年 | 1363篇 |
2007年 | 1318篇 |
2006年 | 1236篇 |
2005年 | 1154篇 |
2004年 | 971篇 |
2003年 | 939篇 |
2002年 | 887篇 |
2001年 | 236篇 |
2000年 | 209篇 |
1999年 | 182篇 |
1998年 | 185篇 |
1997年 | 124篇 |
1996年 | 103篇 |
1995年 | 91篇 |
1994年 | 99篇 |
1993年 | 85篇 |
1992年 | 119篇 |
1991年 | 130篇 |
1990年 | 114篇 |
1989年 | 87篇 |
1988年 | 88篇 |
1987年 | 93篇 |
1986年 | 84篇 |
1985年 | 76篇 |
1984年 | 67篇 |
1983年 | 60篇 |
1982年 | 48篇 |
1981年 | 46篇 |
1980年 | 35篇 |
1979年 | 39篇 |
1978年 | 26篇 |
1977年 | 27篇 |
1976年 | 20篇 |
1975年 | 23篇 |
1972年 | 20篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
Ana Paula Rachid Margarida Moncada Maria Fernanda de Mesquita Jos Brito Maria Alexandra Bernardo Maria Leonor Silva 《Nutrients》2022,14(8)
Cinnamon is a spice used in traditional cuisine that has been investigated due to hypoglycemic properties. The objective of this study was to investigate the effect of aqueous cinnamon extract on postprandial glycemia levels in type 2 diabetes mellitus (DM2) adults. This clinical trial enrolled 36 adults with DM2, randomly allocated in two groups: the control group (n = 18) took only an oral glucose tolerance test (OGTT) and the intervention group (n = 18) took OGTT immediately followed by aqueous cinnamon extract (6 g/100 mL) ingestion. Blood glucose levels were measured on fasting and after 30, 60, 90 and 120 min in both groups. The chemical analysis of the aqueous cinnamon extract included total phenols content determination and antioxidant activity assessment through FRAP and DPPH methods. The data reveal that aqueous cinnamon extract ingestion did not show a significant difference in the incremental area under the curve (p = 0.834), maximum glucose concentration (p = 0.527) and glucose concentration variation (p = 0.873) compared with the control group. Cinnamon extract possess a total phenol content of 1554.9 mg/L gallic acid equivalent and a strong antioxidant capacity, revealed by the DPPH (5125.0 µmol Trolox/L) and FRAP (3658.8 µmol Trolox/L) tests. Aqueous cinnamon extract did not significantly influence postprandial glucose response in diabetic patients during an OGTT. 相似文献
992.
993.
ABSTRACTIntroduction: Stenotrophomonas maltophilia is a prototype of bacteria intrinsically resistant to antibiotics. The reduced susceptibility of this microorganism to antimicrobials mainly relies on the presence in its chromosome of genes encoding efflux pumps and antibiotic inactivating enzymes. Consequently, the therapeutic options for treating S. maltophilia infections are limited.Areas covered: Known mechanisms of intrinsic, acquired and phenotypic resistance to antibiotics of S. maltophilia and the consequences of such resistance for treating S. maltophilia infections are discussed. Acquisition of some genes, mainly those involved in co-trimoxazole resistance, contributes to acquired resistance. Mutation, mainly in the regulators of chromosomally-encoded antibiotic resistance genes, is a major cause for S. maltophilia acquisition of resistance. The expression of some of these genes is triggered by specific signals or stressors, which can lead to transient phenotypic resistance.Expert opinion: Treatment of S. maltophilia infections is difficult because this organism presents low susceptibility to antibiotics. Besides, it can acquire resistance to antimicrobials currently in use. Particularly problematic is the selection of mutants overexpressing efflux pumps since they present a multidrug resistance phenotype. The use of novel antimicrobials alone or in combination, together with the development of efflux pumps’ inhibitors may help in fighting S. maltophilia infections. 相似文献
994.
Débora Fortes Marizeiro Ana Carolina Lins Florêncio Ana Carla Lima Nunes Nataly Gurgel Campos Pedro Olavo de Paula Lima 《Journal of bodywork and movement therapies》2018,22(4):924-929
Background
Although diaphragmatic myofascial release techniques are widely used in clinical practice, few studies have evaluated the simultaneous acute effects of these techniques on the respiratory and musculoskeletal systems.Objective
To evaluate the immediate effects of diaphragmatic myofascial release in sedentary women on the posterior chain muscle flexibility; lumbar spine range of motion; respiratory muscle strength; and chest wall mobility.Design
A randomized placebo-controlled trial with concealed allocation, intention-to-treat analysis, and blinding of assessors and participants.Participants
Seventy-five sedentary women aged between 18 and 35 years.Intervention
The sample was randomly allocated into one of two groups; the experimental group received two diaphragmatic myofascial release techniques in a single session, and the control group received two placebo techniques following the same regimen.Outcomes measures
The primary outcome was chest wall mobility, which was analyzed using cirtometry. The secondary outcomes were flexibility, lumbar spine range of motion, and respiratory muscle strength. Outcomes were measured before and immediately after treatment.Results
The manual diaphragm release techniques significantly improved chest wall mobility immediately after intervention, with a between-group difference of 0.61 cm (95% CI, 0.12–1.1) for the axillary region, 0.49 cm (95% CI, 0.03–0.94) for the xiphoid region, and 1.44 (95% CI, 0.88–2.00) for the basal region. The techniques also significantly improved the posterior chain muscle flexibility, with a between-group difference of 5.80 cm (95% CI, 1.69–9.90). All movements except flexion of the lumbar spine significantly increased. The effects on respiratory muscle strength were non-significant.Conclusion
The diaphragmatic myofascial release techniques improve chest wall mobility, posterior chain muscle flexibility, and some movements of the lumbar spine in sedentary women. These techniques could be considered in the management of people with reduced chest wall and lumbar mobility.Trial registration
NCT03065283. 相似文献995.
PURPOSE: To determine both the efficacy of and compliance with the ketogenic diet in the adolescent population. METHODS: A retrospective study of 45 patients, aged 12-19 years, consecutively enrolled in a ketogenic diet program from 1994 to 2002, was performed. Thirty-seven patients were from The Johns Hopkins Medical Institutions; eight were from The University of Texas at Houston. Charts were reviewed, and patients were contacted by telephone. RESULTS: Six months after diet initiation, 28 (62%) of 45 remained on the ketogenic diet, with six (21%) of 28 having 50-90% seizure reduction, and eight (29%) of 28 having >90%. At 12 months, 20 (44%) of 45 remained on the diet, with seven (35%) of 20 having 50-90% seizure reduction and six (30%) of 20 achieving >90% efficacy. Only 22% discontinued the diet for perceived restrictiveness. The mean diet duration was 1.2 years. Patients with multiple seizure types did best, whereas gender, prior seizure frequency, diet ratio, and age did not influence outcome. Patients dependent on parents for daily care were more likely to remain on the diet at 6 months, but had less efficacy. Weight loss (60%) and menstrual dysfunction (45% of female subjects) were the most commonly reported side effects. CONCLUSIONS: The ketogenic diet is as well tolerated and efficacious for adolescents with epilepsy as for the general childhood population. 相似文献
996.
Stroke is a disease with well-defined modifiable risk factors such as arterial hypertension, smoking, diabetes, hyperlipidemia and atrial fibrillation. The need of new risk factors is based on the fact that only half the cardiovascular disease risk is explained by conventional risk factors. Inflammatory markers, infection, homocysteine and sleep-disordered breathing rank as the four most important new risk factors in cerebral atherosclerosis. C-reactive protein is the inflammatory marker that has been most thoroughly studied. Elevated concentrations of C-reactive protein increase the risk of heart disease and thromboembolic stroke in men and women. The role of Chlamydia pneumoniae is still controversial. Influenza vaccination is a simple and effective preventive measure against stroke. Despite the potential relationship between homocysteine and stroke, we should wait to the results of the ongoing trials to know if the reduction of homocysteine levels with vitamin therapy is of clinical benefit. Sleep-disordered breathing is a potential new risk factor with an effective therapy. Neurologists should not forget to look for sleep disorders in their stroke patients and probably manage them with breathing therapy from the acute phase. 相似文献
997.
998.
999.
Roberta Bottega Alessandro Pecci Erica De Candia Nuria Pujol-Moix Paula G. Heller Patrizia Noris Daniela De Rocco Gian Marco Podda Ana C. Glembotsky Marco Cattaneo Carlo L. Balduini Anna Savoia 《Haematologica》2013,98(6):868-874
The gray platelet syndrome is a rare inherited bleeding disorder characterized by macrothrombocytopenia and deficiency of alpha (α)-granules in platelets. The genetic defect responsible for gray platelet syndrome was recently identified in biallelic mutations in the NBEAL2 gene. We studied 11 consecutive families with inherited macrothrombocytopenia of unknown origin and α-granule deficiency. All of them underwent NBEAL2 DNA sequencing and evaluation of the platelet phenotype, including a systematic assessment of the α-granule content by immunofluorescence analysis for α-granule secretory proteins. We identified 9 novel mutations hitting the two alleles of NBEAL2 in 4 probands. They included missense, nonsense and frameshift mutations, as well as nucleotide substitutions that altered the splicing mechanisms as determined at the RNA level. All the individuals with NBEAL2 biallelic mutations showed almost complete absence of platelet α-granules. Interestingly, the 13 individuals assumed to be asymptomatic because carriers of a mutated allele had platelet macrocytosis and significant reduction of the α-granule content. However, they were not thrombocytopenic. In the remaining 7 probands, we did not identify any NBEAL2 alterations, suggesting that other genetic defect(s) are responsible for their platelet phenotype. Of note, these patients were characterized by a lower severity of the α-granule deficiency than individuals with two NBEAL2 mutated alleles. Our data extend the spectrum of mutations responsible for gray platelet syndrome and demonstrate that macrothrombocytopenia with α-granule deficiency is a genetic heterogeneous trait. In terms of practical applications, the screening of NBEAL2 is worthwhile only in patients with macrothrombocytopenia and severe reduction of the α-granules. Finally, individuals carrying one NBEAL2 mutated allele have mild laboratory abnormalities, suggesting that even haploinsufficiency has an effect on platelet phenotype. 相似文献
1000.
Restoration of Cerebral and Systemic Microvascular Architecture in APP/PS1 Transgenic Mice Following Treatment with Liraglutide™
下载免费PDF全文
![点击此处可从《Microcirculation (New York, N.Y. : 1994)》网站下载免费的PDF全文](/ch/ext_images/free.gif)