全文获取类型
收费全文 | 2247篇 |
免费 | 117篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 18篇 |
儿科学 | 66篇 |
妇产科学 | 23篇 |
基础医学 | 241篇 |
口腔科学 | 27篇 |
临床医学 | 234篇 |
内科学 | 594篇 |
皮肤病学 | 48篇 |
神经病学 | 229篇 |
特种医学 | 37篇 |
外科学 | 203篇 |
综合类 | 17篇 |
预防医学 | 108篇 |
眼科学 | 17篇 |
药学 | 363篇 |
中国医学 | 5篇 |
肿瘤学 | 147篇 |
出版年
2023年 | 36篇 |
2022年 | 53篇 |
2021年 | 80篇 |
2020年 | 28篇 |
2019年 | 37篇 |
2018年 | 51篇 |
2017年 | 39篇 |
2016年 | 50篇 |
2015年 | 36篇 |
2014年 | 64篇 |
2013年 | 73篇 |
2012年 | 116篇 |
2011年 | 147篇 |
2010年 | 66篇 |
2009年 | 71篇 |
2008年 | 117篇 |
2007年 | 136篇 |
2006年 | 94篇 |
2005年 | 98篇 |
2004年 | 76篇 |
2003年 | 85篇 |
2002年 | 64篇 |
2001年 | 45篇 |
2000年 | 52篇 |
1999年 | 44篇 |
1998年 | 18篇 |
1996年 | 12篇 |
1994年 | 14篇 |
1992年 | 59篇 |
1991年 | 51篇 |
1990年 | 46篇 |
1989年 | 33篇 |
1988年 | 25篇 |
1987年 | 28篇 |
1986年 | 34篇 |
1985年 | 37篇 |
1984年 | 18篇 |
1983年 | 18篇 |
1981年 | 14篇 |
1979年 | 13篇 |
1978年 | 13篇 |
1977年 | 24篇 |
1976年 | 11篇 |
1974年 | 15篇 |
1973年 | 10篇 |
1972年 | 15篇 |
1971年 | 12篇 |
1970年 | 12篇 |
1969年 | 14篇 |
1968年 | 9篇 |
排序方式: 共有2377条查询结果,搜索用时 15 毫秒
101.
Esophageal stenosis due to an intrinsic congenital malformation is uncommon in infants and children. Congenital esophageal stenosis is classified by Findlay1 as follows: (1) narrowing of the lumen, (2) membranous diaphragm, (3) fibrous or fibromuscular thickening of wall, (4) spasm.A rare case of congenital esophageal stenosis with lack of the submucosa is presented. 相似文献
102.
Stein RJ Haddock CK Poston WS Catanese D Spertus JA 《Public health reports (Washington, D.C. : 1974)》2005,120(3):266-270
OBJECTIVE: Weight assessment is a critical aid in patient care. It is particularly important in monitoring progression of pregnancies, heart failure status, and when adjusting medications. Although weight is generally determined using a scale, few studies have evaluated the precision of non-household scales. The objective of this study was to assess scale precision across a variety of settings. METHODS: An evaluation of scales from randomly selected primary care clinics (n=30), diabetology/endocrinology clinics (n=7), weight loss facilities (n=25), and fitness centers (n=30) was performed. Assessments were completed on a total of 223 scales: 94 from primary care clinics, 32 from diabetology/endocrinology clinics, 39 from weight loss centers, and 58 from fitness centers. Scales were assessed for condition, location in facility, resting surface, commercial designation, and calibration history. Scale precision was validated using 100 lb. (45.5 kg), 150 lb. (68.3 kg), 200 lb. (90.9 kg), and 250 lb. (113.6 kg) certified weights. RESULTS: Overall, scales demonstrated decreased precision with increased weight. At higher weights, more than 15% of scales were off by more than 6 lbs. (2.3 kg), approximately 1 Body Mass Index (BMI) unit. While facility type was not significant, condition, location in facility, resting surface, commercial designation, and calibration history were significant. CONCLUSIONS: This study demonstrates that many scales used to measure body weight are imprecise and that scales in health care settings are no more precise than those in other facilities. Clinical decisions based on scales that are imprecise have the potential to cause iatrogenic complications in patient care. 相似文献
103.
104.
Interaction of muscarinic drugs with their receptor was studied in the logitudinal muscle of guinea pig ileum. The pD2-value, the index for agonistic activity of a partial agonist was practically equal to its pA2-value, the index for competitive antagonistic activity and to its pKA-value which was a negative logarithm of a dissociation constant (KA), suggesting that the muscarinic drugs such as full and partial agonists and a competitive antagonist interacted with one binding site in the muscarinic receptor. Effects of a GTP-analogue, Gpp(NH)p (guanyl-5'-y limidodiphosphate) decreased affinities of full and partial agonists to the muscarinic receptor in a manner that was correlated with their efficacies. A relationship between the Hill's coefficients of the muscarinic drugs and their efficacies suggest that the ability to distinguish the agonist binding sites was related to their efficacy. 相似文献
105.
106.
Risa Sharon Weiner M.S. J. Richard Woy Ph.D. Steven S. Sharfstein M.D. Rosalyn D. Bass M.A. 《Community mental health journal》1979,15(2):129-138
What happens to community mental health centers when federal funding ends? Analysis of the funding patterns of a cohort of “graduate” community mental health centers indicates that these centers remained fiscally viable subsequent to termination of basic federal grants. However, further analysis revealed two distinct funding patterns within the cohort. One group relied primarily on increased third-party reimbursements to offset the end of basic federal grants. The other sought more state funds and additional federal grants available through the Community Mental Health Center Amendments of 1975. As more centers “graduate”, federal “floor funding” may be necessary to insure the survival of some of them. 相似文献
107.
Maternal dietary supplementation with pomegranate juice is neuroprotective in an animal model of neonatal hypoxic-ischemic brain injury 总被引:2,自引:0,他引:2
Neonatal hypoxic-ischemic brain injury remains a significant cause of morbidity and mortality and lacks effective therapies for prevention and treatment. Recently, interest in the biology of polyphenol compounds has led to the discovery that dietary supplementation with foods rich in polyphenols (e.g. blueberries, green tea extract) provides neuroprotection in adult animal models of ischemia and Alzheimer's disease. We sought to determine whether protection of the neonatal brain against a hypoxic-ischemic insult could be attained through supplementation of the maternal diet with pomegranate juice, notable for its high polyphenol content. Mouse dams were provided ad libitum access to drinking water with pomegranate juice, at one of three doses, as well as plain water, sugar water, and vitamin C water controls during the last third of pregnancy and throughout the duration of litter suckling. At postnatal day 7, pups underwent unilateral carotid ligation followed by exposure to 8% oxygen for 45 min. Brain injury was assessed histologically after 1 wk (percentage of tissue area loss) and biochemically after 24 h (caspase-3 activity). Dietary supplementation with pomegranate juice resulted in markedly decreased brain tissue loss (>60%) in all three brain regions assessed, with the highest pomegranate juice dose having greatest significance (p < or = 0.0001). Pomegranate juice also diminished caspase-3 activation by 84% in the hippocampus and 64% in the cortex. Ellagic acid, a polyphenolic component in pomegranate juice, was detected in plasma from treated but not control pups. These results demonstrate that maternal dietary supplementation with pomegranate juice is neuroprotective for the neonatal brain. 相似文献
108.
109.
Kumakura N Takayanagi M Hasegawa T Ihara K Yano H Kimizuka M 《Archives of physical medicine and rehabilitation》2002,83(9):1245-1251
OBJECTIVE: To determine the time course of secondary worsening of difficulties (SWD) experienced by postpolio and spinal cord injury (SCI) subjects in the general population. DESIGN: Self-report survey. SETTING: Multicenter study in general community in Japan. PARTICIPANTS: A total of 662 postpolio and 736 SCI subjects who had had contact with some rehabilitation facility. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Respondents completed a questionnaire about demographic factors, physical complaints, activities of daily living (ADLs), social participation, and a visual analog scale of time course for difficulties (VAST-D) devised for the present study in which the subjects drew a single curve to indicate the lifetime course of disability as they perceived it. RESULTS: Signs of SWD in all extremities of the polio patients and in the upper extremities of the SCI subjects were visually shown by the VAST-D. Additionally, the prevalence of postpolio syndrome and SWD in the SCI group was estimated to be 55.3% and 45.1%, respectively. CONCLUSIONS: SWD was visually shown by the VAST-D in polio and SCI subjects. 相似文献
110.