全文获取类型
收费全文 | 691篇 |
免费 | 35篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 17篇 |
妇产科学 | 22篇 |
基础医学 | 112篇 |
口腔科学 | 61篇 |
临床医学 | 38篇 |
内科学 | 164篇 |
皮肤病学 | 7篇 |
神经病学 | 40篇 |
特种医学 | 41篇 |
外科学 | 108篇 |
综合类 | 3篇 |
预防医学 | 61篇 |
眼科学 | 7篇 |
药学 | 19篇 |
中国医学 | 3篇 |
肿瘤学 | 21篇 |
出版年
2023年 | 10篇 |
2022年 | 18篇 |
2021年 | 24篇 |
2020年 | 18篇 |
2019年 | 29篇 |
2018年 | 27篇 |
2017年 | 18篇 |
2016年 | 38篇 |
2015年 | 26篇 |
2014年 | 30篇 |
2013年 | 31篇 |
2012年 | 53篇 |
2011年 | 57篇 |
2010年 | 25篇 |
2009年 | 18篇 |
2008年 | 48篇 |
2007年 | 29篇 |
2006年 | 30篇 |
2005年 | 26篇 |
2004年 | 30篇 |
2003年 | 17篇 |
2002年 | 33篇 |
2001年 | 12篇 |
2000年 | 16篇 |
1999年 | 10篇 |
1998年 | 7篇 |
1997年 | 4篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1966年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有728条查询结果,搜索用时 15 毫秒
1.
Mark A. Trimble Salvador Borges-Neto Stuart Smallhelser Ji Chen Emily F. Honeycutt Linda K. Shaw Jaekyeong Heo Robert A. Pagnanelli E. Lindsey Tauxe Ernest V. Garcia Fabio Esteves Frank Seghatol-Eslami G. Neal Kay Ami E. Iskandrian 《Journal of nuclear cardiology》2007,14(3):298-307
Background Cardiac resynchronization therapy (CRT) is approved for the treatment of patients with advanced systolic heart failure and
evidence of dyssynchrony on electrocardiograms. However, a significant percentage of patients do not demonstrate improvement
with CRT. Echocardiographic techniques have been used for more accurate determination of dyssynchrony. Single photon emission
computed tomography (SPECT) myocardial perfusion imaging has not previously been used to evaluate cardiac dyssynchrony. The
objective of this study is to evaluate mechanical dyssynchrony as described by phase analysis of gated SPECT images in patients
with left ventricular dysfunction, conduction delays, and ventricular paced rhythms.
Methods and Results A novel count-based method is used to extract regional systolic wall thickening amplitude and phase from gated SPECT images.
Five indices describing the phase dispersion of the onset of mechanical contraction are determined: peak phase, phase SD,
bandwidth, skewness, and kurtosis. These indices were determined in consecutive patients with left ventricular dysfunction
(n=120), left bundle branch block (n=33), right bundle branch block (n=19), and ventricular paced rhythms (n=23) and were
compared with normal control subjects (n=157). Phase SD, bandwidth, skewness, and kurtosis were significantly different between
patients with left ventricular dysfunction, left bundle branch block, right bundle branch block, and ventricular paced rhythms
and normal control subjects (all P<.001) Peak phase was significantly different between patients with right ventricular paced rhythms and normal control subjects
(P=.001).
Conclusions A novel SPECT technique for describing left ventricular mechanical dyssyn-chrony has been developed and may prove useful in
the evaluation of patients for CRT.
This study was funded in part by a research grant from the Medtronic-Duke Strategic Alliance, of which Dr Borges-Neto is the
primary investigator. 相似文献
2.
A Basile-Filho A C Campos S C Esteves S Bordin M Mantovani 《Nutrition (Burbank, Los Angeles County, Calif.)》1991,7(4):280-282
Several studies have reported that the heart is severely affected by chronic malnutrition. However, the influence of these alterations on cardiac function remains unclear. The aim of this study was to evaluate the effects of subacute starvation on the heart chronotropic response to a beta-adrenergic agonist (isoproterenol). Twelve rats were fed rat chow ad libitum or a 50%-restricted diet for 17 days. The rats were killed, the right atrium was isolated and incubated, and in vitro spontaneous cardiac contractions and frequency were registered. Cumulative doses of isoproterenol were added to the solution until maximal cardiac frequency was achieved. A deficit of 25% in the weight gain was observed in study rats compared with controls (92.6 +/- 10.2 vs. 113.8 +/- 19.2 g, p less than 0.05). Mean daily food intake was 4.8 +/- 0.1 and 9.8 +/- 0.5 g/day for semistarved and control rats, respectively. The in vitro cardiac frequency of the semistarved rats was similar to that of controls (290 +/- 15 and 305 +/- 23 beats/min, respectively, NS). However, when isoproterenol was added to the solution, maximal cardiac frequency of the semistarved rats (435 +/- 51 beats/min) was lower than that of control rats (508 +/- 34 beats/min, p less than 0.005). These findings suggest that subacute starvation may alter the cardiac response to beta-adrenergic agonists. 相似文献
3.
António Travassos Susana Teixeira Pinto Ferreira Isaura Regadas Ana Sofia Travassos Florindo Esteves Esperancinha Isabel Prieto Grapa Pires Robert van Velze A Valido Maria do Céu Machado 《Ophthalmic surgery, lasers & imaging》2007,38(3):233-237
The anatomic response to intravitreal bevacizumab injection in three patients with aggressive, posterior retinopathy of prematurity is described. In all cases, the worse eye was treated with a single intravitreal injection of 0.75 mg of bevacizumab as monotherapy or complementary to laser therapy. In 24 hours, all injected eyes showed regression of the tunica vasculosa lentis and iris vessel engorgement and disappearance of iris rigidity. In addition, plus disease and retinal proliferation began to regress. None of the eyes required additional treatment. Follow-up of up to 10 months 相似文献
4.
Quantitative (82)Rb PET/CT: development and validation of myocardial perfusion database. 总被引:1,自引:0,他引:1
Cesar A Santana Russell D Folks Ernest V Garcia Liudmila Verdes Rupan Sanyal Jon Hainer Marcelo F Di Carli Fabio P Esteves 《Journal of nuclear medicine》2007,48(7):1122-1128
The use of myocardial perfusion (82)Rb PET/CT studies continues to increase but its accuracy using database quantification methods for the diagnosis of coronary artery disease (CAD) has not been established. METHODS: A sex-independent normal database and criteria for abnormality for rest-stress (82)Rb PET/CT myocardial perfusion imaging were developed and validated by evaluation of 281 patients (136 females: mean age +/- SD, 63.3 +/- 13.3 y; 145 males: mean age +/- SD, 63.9 +/- 12.8 y) who underwent a rest-adenosine stress (82)Rb PET/CT study. These patients were divided into 3 groups: (a) healthy group: 30 patients, with <5% likelihood of CAD (low likelihood [LLK]) based on sequential Bayesian analysis; these patients were used to generate the normal distribution; (b) pilot group: 174 patients; these patients were used to determine the optimal criteria for detecting and localizing the perfusion abnormality; and (c) validation group: 76 patients (23 with LLK of CAD and 53 who underwent coronary angiography; these patients were used for prospective validation. RESULTS: Of the 53 patients who underwent coronary angiography, 8 had <50% stenosis and 45 patients had at least one stenosis > or =50% in one major artery. Fifteen patients had single-vessel disease, 17 had double-vessel disease, and 13 had triple-vessel disease. The prospective validation shows a normalcy rate of 78% (18/23) for global CAD. The analyses by individual arteries show a normalcy rate of 96% (22/23) for the left anterior descending coronary artery, 96% for the left circumflex coronary artery (22/23), and 100% for the right coronary artery (23/23). The overall sensitivity for detection of CAD (> or =50% stenosis) was 93% (42/45). The overall specificity for detection of the absence of CAD (< or =50% stenosis) was 75% (6/8). Also, the positive predictive value for global CAD was 95% (42/44), the negative predictive value was 67% (6/9), and the accuracy was 91% (48/53). CONCLUSION: The quantitative (82)Rb PET/CT database created and validated in this study is highly accurate for the detection and localization of CAD. Physicians should consider using the quantitative output of these algorithms as decision support tools to aid with image interpretation. 相似文献
5.
Helicobacter pylori gastritis in cats with long-term natural infection as a model of human disease
下载免费PDF全文
![点击此处可从《The American journal of pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Esteves MI Schrenzel MD Marini RP Taylor NS Xu S Hagen S Feng Y Shen Z Fox JG 《The American journal of pathology》2000,156(2):709-721
A natural infection with Helicobacter pylori (H. pylori) in domestic cats (Felis cattus) less than 2 years of age has been well described in a closed colony of animals. Six cats from this colony that were serially evaluated by culture, polymerase chain reaction, and light and electron microscopy for a period of 3 years demonstrated persistent gastric colonization with a single cag(-) vac(+) strain of H. pylori. In these cats, as well as five other 5- to 6-year-old cats that were examined, a long-term infection resulted in chronic diffuse lymphofollicular atrophic gastritis with areas of mucosal dysplasia in the antrum and predominantly midsuperficial gastritis in the body and cardia. Topographically, the distribution of lesions was similar in both young and older cats and closely resembled that found in humans, with the most severe changes occurring in the gastric antrum. Few granulocytes and no significant elevation in mast cells were seen in older H. pylori-infected cats compared with uninfected controls; however, marked increases in interepithelial globule leukocytes and numerous active mucosal lymphoid follicles were present in infected animals. Indices of gastritis were significantly greater in older infected cats when compared with uninfected controls and younger cats (P < 0.05). The antral cell proliferation index of infected older cats was significantly (P = 0.021) greater than that of uninfected controls. Apoptotic indices of the gastric antrum and body of infected cats were significantly (P = 0.01) increased versus controls. Chronic infection with H. pylori in cats shares many features of long-term H. pylori infection in humans, including the development of preneoplastic processes. This similarity provides useful, comparative insights into host-pathogen interactions. 相似文献
6.
Cross-reactions between immunoglobulins from twelve mammalian species were observed by immunoelectrophoresis with antisera prepared in rabbits against the purified IgG of each species. The Fc fragments of the IgG from man, pig, goat, sheep and cow were compared by examination of the cross-reactions before and after absorption of the antisera with the various IgG. Eight antigenic determinants could be detected; some of them were species-specific, others were shared by IgG from two or more species. A close resemblance was found between goat, sheep and cow IgG. 相似文献
7.
Szwarcwald CL Bastos FI Esteves MA de Andrade CL Paez MS Medici EV Derrico M 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》1999,15(1):15-28
This ecological analysis addresses the association between income inequality and health status in the municipality of Rio de Janeiro. Data were analyzed using geo-processing and multiple regression techniques. The following health indicators were used: infant mortality rate; standardized mortality rate; life expectancy at birth; and homicide rate among 15-29-year-old males. Patterns of income inequality were assessed through income distribution indicators: Gini index, Robin Hood index, and top 10 %/bottom 40% average income ratio. The results indicate significant correlations between income distribution indicators and health indicators, providing additional empirical evidence of the association between health status and income inequality. For the homicide rate, the effect of the indicator "density of slum residents" was also relevant, suggesting that further deterioration in health standards may be due to social disruption of deprived communities and the resultant increase in criminal activity. The geo-epidemiological analysis presented here highlights the association between adverse health outcomes and residential concentration of poverty. Social policies focused on slum residents are needed to reduce the harmful effects of relative deprivation. 相似文献
8.
Ana Teresa Martins Luis Faísca Francisco Esteves Cláudia Simo Mariline Gomes Justo Angélica Muresan Alexandra Reis 《中国神经再生研究》2012,7(2):101-108
Changes in social and emotional behaviour have been consistently observed in patients with traumatic brain injury. These changes are associated with emotion recognition deficits which represent one of the major barriers to a successful familiar and social reintegration. In the present study, 32 patients with traumatic brain injury, involving the frontal lobe, and 41 ageand education-matched healthy controls were analyzed. A Go/No-Go task was designed, where each participant had to recognize faces representing three social emotions (arrogance, guilt and jealousy). Results suggested that ability to recognize two social emotions (arrogance and jealousy) was significantly reduced in patients with traumatic brain injury, indicating frontal lesion can reduce emotion recognition ability. In addition, the analysis of the results for hemispheric lesion location (right, left or bilateral) suggested the bilateral lesion sub-group showed a lower accuracy on all social emotions. 相似文献
9.
Emphysema induced by elastase enhances acute inflammatory pulmonary response to intraperitoneal LPS in rats
下载免费PDF全文
![点击此处可从《International journal of experimental pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Lídia Maria Carneiro da Fonseca Maycon Moura Reboredo Leda Marília Fonseca Lucinda Thaís Fernanda Fazza Maria Aparecida Esteves Rabelo Adenilson Souza Fonseca Flavia de Paoli Bruno Valle Pinheiro 《International journal of experimental pathology》2016,97(6):430-437
Abnormalities in lungs caused by emphysema might alter their response to sepsis and the occurrence of acute lung injury (ALI). This study compared the extension of ALI in response to intraperitoneal lipopolysaccharide (LPS) injection in Wistar rats with and without emphysema induced by elastase. Adult male Wistar rats were randomized into four groups: control, emphysema without sepsis, normal lung with sepsis and emphysema with sepsis. Sepsis was induced, and 24 h later the rats were euthanised. The following analysis was performed: blood gas measurements, bronchoalveolar lavage (BAL), lung permeability and histology. Animals that received LPS showed significant increase in a lung injury scoring system, inflammatory cells in bronchoalveolar lavage (BAL) and IL‐6, TNF‐α and CXCL2 mRNA expression in lung tissue. Animals with emphysema and sepsis showed increased alveolocapillary membrane permeability, demonstrated by higher BAL/serum albumin ratio. In conclusion, the presence of emphysema induced by elastase increases the inflammatory response in the lungs to a systemic stimulus, represented in this model by the intraperitoneal injection of LPS. 相似文献
10.
Sol Esteves Diana Andrea Ramirez Romero Teresa Torralva Macarena Martínez Cuitiño Shannon Herndon Blas Couto 《Neurocase》2018,24(1):16-30
Posterior cortical atrophy (PCA) is a rare neurodegenerative syndrome characterized by initial predominant visuoperceptual deficits followed by a progressive decline in other cognitive functions. This syndrome has not been as thoroughly described as other dementias, particularly from a neuropsychological evolution perspective with only a few studies describing the evolution of its cognitive progression. In this investigation we review the literature on this rare condition and we perform a 7-year neuropsychological and neuroradiological follow-up of a 64-year-old man with PCA. The subject’s deficits initially appeared in his visuoperceptual skills with later affectation appearing in language and other cognitive functions, this being coherent with the patient’s parieto-temporal atrophy evolution. 相似文献