收费全文 | 3899篇 |
免费 | 175篇 |
国内免费 | 29篇 |
耳鼻咽喉 | 84篇 |
儿科学 | 237篇 |
妇产科学 | 181篇 |
基础医学 | 269篇 |
口腔科学 | 278篇 |
临床医学 | 207篇 |
内科学 | 715篇 |
皮肤病学 | 75篇 |
神经病学 | 282篇 |
特种医学 | 301篇 |
外科学 | 938篇 |
综合类 | 29篇 |
一般理论 | 1篇 |
预防医学 | 113篇 |
眼科学 | 66篇 |
药学 | 101篇 |
中国医学 | 1篇 |
肿瘤学 | 225篇 |
2024年 | 4篇 |
2023年 | 33篇 |
2022年 | 67篇 |
2021年 | 121篇 |
2020年 | 92篇 |
2019年 | 99篇 |
2018年 | 123篇 |
2017年 | 113篇 |
2016年 | 146篇 |
2015年 | 172篇 |
2014年 | 175篇 |
2013年 | 209篇 |
2012年 | 283篇 |
2011年 | 285篇 |
2010年 | 159篇 |
2009年 | 135篇 |
2008年 | 223篇 |
2007年 | 248篇 |
2006年 | 215篇 |
2005年 | 187篇 |
2004年 | 151篇 |
2003年 | 111篇 |
2002年 | 141篇 |
2001年 | 71篇 |
2000年 | 77篇 |
1999年 | 63篇 |
1998年 | 29篇 |
1997年 | 25篇 |
1996年 | 26篇 |
1995年 | 26篇 |
1994年 | 11篇 |
1993年 | 11篇 |
1992年 | 42篇 |
1991年 | 31篇 |
1990年 | 30篇 |
1989年 | 29篇 |
1988年 | 26篇 |
1987年 | 20篇 |
1986年 | 14篇 |
1985年 | 14篇 |
1984年 | 12篇 |
1979年 | 8篇 |
1976年 | 7篇 |
1973年 | 4篇 |
1972年 | 3篇 |
1971年 | 4篇 |
1969年 | 3篇 |
1967年 | 3篇 |
1966年 | 3篇 |
1965年 | 3篇 |
Methods: A total of 40 women, of which 20 who had previously received the diagnosis of CI and 20 healty women were included in the study. None of the women were pregnant. All subjects underwent sonographic evaluation including cervical length measurement and ES of uterine cervix. Adjacent muscular tissue was the reference point for elastosonography evaluation. Tissue strain ratio values were obtained from all the patients.
Results: The area around the internal cervical os of the group with CI was found to be significantly softer as compared to the control group (higher SR rate, p?<?0.05). Furthermore, the outer parts of the cervix (sites A and D) were also found harder in the group that had CI (lower SR rate, p?<?0.05).
Conclusions: According to our knowledge, this is preliminary study to evaluate the predictive value of cervical ES in CI and we concluded that ES can be used as reliable method to determine CI but it is necessary to be studied in different cohort groups. 相似文献
Purpose
Cardiovascular disease (CVD) due to atherosclerosis is the leading cause of early mortality and morbidity. The current European guidelines on CVD prevention in clinical practice recommend the use of the Systematic Coronary Risk Estimation (SCORE) system. The current American Heart Association guidelines recommend the use of the new pooled cohort risk assessment equations to estimate the 10-year atherosclerotic CVD risk. The purpose of this article was to investigate the compliance of dyslipidemia guidelines in daily practice in patients with dyslipidemia or who have risk factors for CVD.Methods
The study group consisted of 500 outpatients who had dyslipidemia or risk factors for CVD. The risk level was computed according to the European and American Heart Association guidelines. Therapeutic LDL-C targets were identified based on the calculated risk level. Therapeutic target levels were compared based on the dosage of statins used and achievement of the LDL-C goal in daily practice according to the risk levels.Findings
According to the European dyslipidemia guidelines, 231 patients were in the very-high/high-risk group, and 106 patients (45.9%) achieved the LDL-C target (<100 mg/dL); 210 patients were in the moderate-risk group, and 156 (74.3%) patients achieved the LDL-C target (<115 mg/dL); and 59 patients were in the low-risk group, and 55 (93.2%) patients achieved the LDL-C target (<155 mg/dL). Univariate and multivariate logistic regression analyses revealed that the LDL-C level and presence of coronary artery disease were significantly reverse associated with achievement of the LDL-C goal (both, P < 0.001).Implications
Our results showed that the majority of patients were in the very-high/high-risk group in daily practice. Although the European dyslipidemia guidelines are more likely to be used in daily practice, achievement of the guidelines-recommended treatment goals was low. 相似文献Hypophysitis is a heterogeneous condition that includes inflammation of the pituitary gland and infundibulum, and it can cause symptoms related to mass effects and hormonal deficiencies. We aimed to evaluate the potential role of machine learning methods in differentiating hypophysitis from non-functioning pituitary adenomas.
MethodsThe radiomic parameters obtained from T1A-C images were used. Among the radiomic parameters, parameters capable of distinguishing between hypophysitis and non-functioning pituitary adenomas were selected. In order to avoid the effects of confounding factors and to improve the performance of the classifiers, parameters with high correlation with each other were eliminated. Machine learning algorithms were performed with the combination of gray-level run-length matrix-low gray level run emphasis, gray-level co-occurrence matrix-correlation, and gray-level co-occurrence entropy.
ResultsA total of 34 patients were included, 17 of whom had hypophysitis and 17 had non-functioning pituitary adenomas. Among the 38 radiomics parameters obtained from post-contrast T1-weighted images, 10 tissue features that could differentiate the lesions were selected. Machine learning algorithms were performed using three selected parameters; gray level run length matrix-low gray level run emphasis, gray-level co-occurrence matrix-correlation, and gray level co-occurrence entropy. Error matrices were calculated by using the machine learning algorithm and it was seen that support vector machines showed the best performance in distinguishing the two lesion types.
ConclusionsOur analysis reported that support vector machines showed the best performance in distinguishing hypophysitis from non-functioning pituitary adenomas, emphasizing the importance of machine learning in differentiating the two lesions.
相似文献It was expected that using a comprehensive scale like the Thought and Language Disorder Scale (TALD) for measurement of FTD would enable assessing its heterogeneity and its associations with cognitive impairment and functionality. This study has aimed to analyze the relationship between formal thought disorder (FTD) and cognitive functions, functionality, and quality of life in schizophrenia.
MethodsThis cross-sectional exploratory study included 46 clinical participants meeting the DSM-5 diagnostic criteria for schizophrenia and 35 healthy individuals as the control groups. Data were acquired by means of the Turkish language version of the TALD, the Positive and Negative Syndrome Scale, the Clinical Global Impression Scale, the Functioning Assessment Short Test, the Social Functioning Scale, the World Health Organization Quality of Life Instrument-Short Form, and a neuropsychological test battery on executive functions, working memory, verbal fluency, abstract thinking, and response inhibition. Correlation analyses were conducted to detect significant relationships.
ResultsThe clinical group scored failures in all cognitive tests. The objective positive FTD was associated with deficits in executive functions and social functioning. The objective negative FTD was associated with poor performance in all cognitive domains, physical quality of life, and social and global functioning. The subjective negative FTD was negatively correlated with psychological quality of life.
ConclusionThis study demonstrated that objective FTD factors reflect different underlying cognitive deficits and correlate with different functioning domains. Significant correlation was determined between subjective negative FTD and psychological quality of life. Given the close relationship of FTD with functioning and quality of life, the FTD-related cognitive deficits should be the key treatment goal in schizophrenia.
相似文献