全文获取类型
收费全文 | 45375篇 |
免费 | 4127篇 |
国内免费 | 537篇 |
专业分类
耳鼻咽喉 | 369篇 |
儿科学 | 2331篇 |
妇产科学 | 569篇 |
基础医学 | 5165篇 |
口腔科学 | 1007篇 |
临床医学 | 5094篇 |
内科学 | 3089篇 |
皮肤病学 | 273篇 |
神经病学 | 17178篇 |
特种医学 | 422篇 |
外国民族医学 | 1篇 |
外科学 | 1693篇 |
综合类 | 3534篇 |
现状与发展 | 2篇 |
一般理论 | 1篇 |
预防医学 | 3810篇 |
眼科学 | 170篇 |
药学 | 3544篇 |
40篇 | |
中国医学 | 1101篇 |
肿瘤学 | 646篇 |
出版年
2024年 | 231篇 |
2023年 | 1155篇 |
2022年 | 1597篇 |
2021年 | 2338篇 |
2020年 | 2327篇 |
2019年 | 2167篇 |
2018年 | 1965篇 |
2017年 | 2050篇 |
2016年 | 2111篇 |
2015年 | 1859篇 |
2014年 | 2972篇 |
2013年 | 4163篇 |
2012年 | 2405篇 |
2011年 | 2845篇 |
2010年 | 2146篇 |
2009年 | 2192篇 |
2008年 | 2256篇 |
2007年 | 2032篇 |
2006年 | 1685篇 |
2005年 | 1454篇 |
2004年 | 1181篇 |
2003年 | 1066篇 |
2002年 | 900篇 |
2001年 | 669篇 |
2000年 | 533篇 |
1999年 | 407篇 |
1998年 | 481篇 |
1997年 | 398篇 |
1996年 | 300篇 |
1995年 | 250篇 |
1994年 | 219篇 |
1993年 | 203篇 |
1992年 | 199篇 |
1991年 | 187篇 |
1990年 | 177篇 |
1989年 | 154篇 |
1988年 | 140篇 |
1987年 | 121篇 |
1986年 | 83篇 |
1985年 | 101篇 |
1984年 | 71篇 |
1983年 | 44篇 |
1982年 | 66篇 |
1981年 | 33篇 |
1980年 | 26篇 |
1979年 | 18篇 |
1978年 | 15篇 |
1977年 | 14篇 |
1976年 | 14篇 |
1974年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
The present experiment explored the utility of finger pulse volume (FPV) as a measure of anxiety. Subjects were exposed to either a threatening or nonthreatening situation, and indices of physiological arousal (pulse rate (PR) and FPV) and self-report of anxiety (Affect Adjective Checklist (AACL)) were collected. Results indicated that FPV was responsive to changes in experimentally induced anxiety and significantly correlated with PR and AACL, although the strength of these relationships was not substantial. Relevance for psychophysiological theory and the clinical observation of anxiety is discussed. 相似文献
102.
Margaret O''Dougherty Gary G. Berntson Sarah T. Boysen Francis S. Wright Douglas Teske 《Psychophysiology》1988,25(3):305-315
Cardiac responses to non-signal stimuli and to signal stimuli in a vigilance task were examined in children born with congenital heart defects (CHD), and in normal and attention deficit disordered (ADD) subjects. Overall task performance was lower in subjects with heart defects and in the ADD group. Cardiac measures revealed that normal children displayed significantly larger heart rate deceleration to the target stimuli than did either of the clinical groups. Moreover, although no group differences were observed in the cardiac response to non-signal auditory stimuli, exaggerated heart rate deceleration was observed to vibrotactile stimuli in both the clinical groups. Regression analyses revealed that the magnitude of the cardiac response to somatosensory stimuli was predictive of task performance (both within and between subject groups), with larger responses associated with higher error rates and lower perceptual sensitivity. Results were suggestive of a predictive relationship between somatosensory reactivity and neuropsychological maturation. 相似文献
103.
Nick Craddock Johanna Daniels Enriqueta Roberts Mark Rees Peter McGuffin Michael J. Owen 《American journal of medical genetics. Part A》1995,60(4):322-324
We have tested the hypothesis that DNA markers in the MAOA gene show allelic association with bipolar affective disorder. Eighty-four unrelated Caucasian patients with DSM III-R bipolar disorder and 84 Caucasian controls were typed for three markers in MAOA: a dinucleotide repeat in intron 2, a VNTR in intron 1, and an Fnu4HI RFLP in exon 8. No evidence for allelic association was observed between any of the markers and bipolar disorder. © 1995 Wiley-Liss, Inc. 相似文献
104.
Perceived parental rearing behaviour in unipolar and bipolar depressed patients. A verification study in an Italian sample 总被引:1,自引:0,他引:1
Two groups of former depressed Italian patients comprising 54 bipolars and 52 unipolars completed the Italian version of the EMBU, a Swedish instrument aimed at assessing the experience of parental rearing behaviour. As in a previous study of Swedish depressives, three factors, "rejection", "emotional warmth", and "over-protection", have been taken into account. The results obtained in the patient group have been compared with those obtained in Italian healthy controls. Depressed patients rated both parents significantly lower than the controls on the factor "emotional warmth". The present results cross-validate those obtained previously in the Swedish depressives and strengthen, together with other findings in the literature, the assumption that the lack of emotional warmth in the parents' rearing practices might be a crucial variable in the pathogenesis of depressive illnesses. 相似文献
105.
The marital adjustment of patients with psychogenic pain disorder was evaluated and compared with a matched group of patients with other neurotic disorders. Pain patients spouses were found to have better marital adjustment and less psychiatric morbidity than the spouses of neurotic patients. These findings are discussed in terms of the concepts of "sick role homeostasis" and "tertiary gain". 相似文献
106.
H J Keegstra 《Acta psychiatrica Scandinavica》1986,73(6):658-664
Fifty-two depressed patients were selected from out-patients at the psychiatric department of St. Paul's Hospital in Addis Ababa. A clinical assessment on each patient was carried out using a slightly revised SADD schedule. The findings were very similar to those from previous SADD studies in different cultures. The same "core" of depressive symptomatology could be detected in Ethiopian depressed patients. Most patients presented with somatic complaints. An interesting finding was that more women than men admitted aggressive feelings or acts. Remarkably few "culture-specific" data were found, which probably is not surprising when using a diagnostic tool with a cultural bias. Suggestions are put forward to explain the difference in frequency of some symptoms in Ethiopian patients compared with patients from other countries. 相似文献
107.
Two distinct patterns of somatization were identified in 807 Swedish adopted men, using comprehensive lifetime psychiatric and sick-leave records. "Diversiform" somatizers had a high frequency of brief sickness occasions for a wide diversity of complaints, particularly pain in the head, joints, and abdomen. "Asthenic" somatizers had a lower frequency and diversity of complaints. They recuperate more slowly, however, and were more often disabled by fatigue, weakness, and minor illnesses such as upper respiratory infections. Both types of somatizers had associated psychosocial maladjustment, but they had discrete clinical patterns, with infrequent overlap. Diversiform somatizers had a higher risk of alcohol abuse, psychiatric hospitalization, and substandard income than either asthenic somatizers or non-somatizers. Asthenic somatizers had a higher risk of divorce than either diversiform somatizers or non-somatizers. Men with prominent somatization had an excess of psychiatric treatment for alcoholism or anxiety disorders, but, unlike female somatizers, no excess of criminality. These clinical differences suggest that the psychiatric processes associated with somatization may be qualitatively different in men and women. The method used here is generally applicable in genetic epidemiology to identify natural clinical subtypes within a heterogeneous phenotype. 相似文献
108.
Vincenzo Di Stefano Raffaele Ornello Andrea Gagliardo Angelo Torrente Elisa Illuminato Valeria Caponnetto Ilaria Frattale Raffaella Golini Chiara Di Felice Fabiola Graziano Maria Caccamo Davide Ventimiglia Salvatore Iacono Gabriella Matarazzo Francesco Armetta Giuseppe Battaglia Alberto Firenze Simona Sacco Filippo Brighina 《Nutrients》2021,13(4)
Background: The restrictions taken to control the rapid spread of COVID-19 resulted in a sudden, unprecedented change in people’s lifestyle, leading to negative consequences on general health. This study aimed to estimate the impact of such changes on migraine severity during 2020 March–May lockdown. Methods: Patients affected by migraine with or without aura, diagnosed by expert physicians, completed a detailed interview comprehensive of: assessment of migraine characteristics; measure of physical activity (PA) levels; measure of the intake frequency of main Italian foods; the Insomnia Severity Index (ISI) questionnaire investigating sleep disorders. Results: We included 261 patients with a mean age of 44.5 ± 12.3 years. During social distancing, 72 patients (28%) reported a headache worsening, 86 (33%) an improvement, and 103 (39%) a stable headache frequency. A significant decrease of the PA levels during COVID-19 quarantine in the whole study sample was observed (median total metabolic equivalent task (METs) decreased from 1170 to 510; p < 0.001). Additionally, a significant difference was reported on median ISI scores (from 7 to 8; p < 0.001), which were increased in patients who presented a stable or worsening headache. Conclusions: Our study confirmed that the restrictions taken during the pandemic have affected the practice of PA levels and sleep quality in migraine. Hence, PA and sleep quality should be assessed to find strategies for an improvement in quality of life. 相似文献
109.
Vanessa S. Sakalidis Alethea Rea Sharon L. Perrella Jacki McEachran Grace Collis Jennifer Miraudo Stuart A. Prosser Lisa Y. Gibson Desiree Silva Donna T. Geddes 《Nutrients》2021,13(6)
During the COVID-19 pandemic, breastfeeding women have experienced restricted access to support, placing them at increased risk of mental health concerns and limited breastfeeding assistance. This study investigated the effect of the pandemic on feeding choices and maternal wellbeing amongst breastfeeding mothers living in Australian and New Zealand. We conducted a cross-sectional online survey that examined feeding methods, maternal mental wellbeing, worries, challenges, and positive experiences during the pandemic. Most women were exclusively breastfeeding (82%). Partial breastfeeding was associated with perceived low milk supply and longer pregnancy duration during the pandemic. Reduced mental health and wellbeing was associated with lower levels of family functioning, increased perceived stress, and perinatal anxiety. Longer pregnancy duration during the pandemic was associated with lower mental health wellbeing scores, while higher perceived stress scores were reported for regions with higher COVID-19 infection rates and women with perceived low milk supply. Women reported that the pandemic resulted in less pressure and more time for family bonding, while worries about the pandemic, family health, and parenting challenges were also cited. Mental health concerns of breastfeeding women appear to be exacerbated by COVID-19, highlighting a critical need for access to mental health and broader family support during the pandemic. 相似文献
110.
Anthony Xiang Wei Hou Sina Rashidian Richard N Rosenthal Kayley Abell-Hart Xia Zhao Fusheng Wang 《JMIR Public Health and Surveillance》2021,7(4)
BackgroundOpioid overdose-related deaths have increased dramatically in recent years. Combating the opioid epidemic requires better understanding of the epidemiology of opioid poisoning (OP) and opioid use disorder (OUD).ObjectiveWe aimed to discover geospatial patterns in nonmedical opioid use and its correlations with demographic features related to despair and economic hardship, most notably the US presidential voting patterns in 2016 at census tract level in New York State.MethodsThis cross-sectional analysis used data from New York Statewide Planning and Research Cooperative System claims data and the presidential voting results of 2016 in New York State from the Harvard Election Data Archive. We included 63,958 patients who had at least one OUD diagnosis between 2010 and 2016 and 36,004 patients with at least one OP diagnosis between 2012 and 2016. Geospatial mappings were created to compare areas of New York in OUD rates and presidential voting patterns. A multiple regression model examines the extent that certain factors explain OUD rate variation.ResultsSeveral areas shared similar patterns of OUD rates and Republican vote: census tracts in western New York, central New York, and Suffolk County. The correlation between OUD rates and the Republican vote was .38 (P<.001). The regression model with census tract level of demographic and socioeconomic factors explains 30% of the variance in OUD rates, with disability and Republican vote as the most significant predictors.ConclusionsAt the census tract level, OUD rates were positively correlated with Republican support in the 2016 presidential election, disability, unemployment, and unmarried status. Socioeconomic and demographic despair-related features explain a large portion of the association between the Republican vote and OUD. Together, these findings underscore the importance of socioeconomic interventions in combating the opioid epidemic. 相似文献