全文获取类型
收费全文 | 4416篇 |
免费 | 258篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 34篇 |
儿科学 | 149篇 |
妇产科学 | 67篇 |
基础医学 | 572篇 |
口腔科学 | 85篇 |
临床医学 | 850篇 |
内科学 | 792篇 |
皮肤病学 | 34篇 |
神经病学 | 406篇 |
特种医学 | 129篇 |
外科学 | 326篇 |
综合类 | 55篇 |
一般理论 | 23篇 |
预防医学 | 607篇 |
眼科学 | 59篇 |
药学 | 210篇 |
1篇 | |
中国医学 | 4篇 |
肿瘤学 | 277篇 |
出版年
2023年 | 15篇 |
2022年 | 40篇 |
2021年 | 103篇 |
2020年 | 57篇 |
2019年 | 93篇 |
2018年 | 112篇 |
2017年 | 99篇 |
2016年 | 53篇 |
2015年 | 94篇 |
2014年 | 129篇 |
2013年 | 246篇 |
2012年 | 306篇 |
2011年 | 327篇 |
2010年 | 214篇 |
2009年 | 163篇 |
2008年 | 287篇 |
2007年 | 312篇 |
2006年 | 297篇 |
2005年 | 314篇 |
2004年 | 297篇 |
2003年 | 262篇 |
2002年 | 253篇 |
2001年 | 39篇 |
2000年 | 34篇 |
1999年 | 24篇 |
1998年 | 53篇 |
1997年 | 43篇 |
1996年 | 30篇 |
1995年 | 40篇 |
1994年 | 27篇 |
1993年 | 26篇 |
1992年 | 24篇 |
1991年 | 19篇 |
1990年 | 20篇 |
1989年 | 18篇 |
1988年 | 12篇 |
1987年 | 19篇 |
1986年 | 17篇 |
1985年 | 16篇 |
1984年 | 19篇 |
1983年 | 20篇 |
1982年 | 20篇 |
1981年 | 21篇 |
1980年 | 15篇 |
1979年 | 11篇 |
1978年 | 8篇 |
1977年 | 7篇 |
1976年 | 6篇 |
1975年 | 5篇 |
1974年 | 6篇 |
排序方式: 共有4680条查询结果,搜索用时 15 毫秒
1.
2.
Kelly H. M. Cooijmans Roseriet Beijers Bonnie E. Brett Carolina de Weerth 《Maternal & child nutrition》2022,18(1):e13241
This randomized controlled trial evaluated the effect of a 5-week daily skin-to-skin contact (SSC) intervention between mothers and their full-term infants, compared with care-as-usual, on exclusive and continued breastfeeding duration during the first post-natal year. Healthy pregnant women (n = 116) from a community sample were enrolled and randomly allocated to the SSC or care-as-usual condition. SSC mothers were requested to provide one daily hour of SSC for the first five post-natal weeks. Twelve months post-partum, mothers indicated the number of exclusive and continued breastfeeding months. Multiple regression analyses were conducted using intention-to-treat, per-protocol and exploratory dose–response frameworks. In intention-to-treat analyses, exclusive and continued breastfeeding duration was not different between groups (exclusive: 3.61 ± 1.99 vs. 3.16 ± 1.77 months; adjusted mean difference 0.28, 95% confidence interval [CI] ?0.33 to 0.89; p = 0.36; continued: 7.98 ± 4.20 vs. 6.75 ± 4.06 months; adjusted mean difference 0.81, 95% CI ?0.46 to 2.08; p = 0.21). In per-protocol analyses, exclusive and continued breastfeeding duration was longer for SSC than care-as-usual dyads (exclusive: 4.89 ± 1.26 vs. 3.25 ± 1.80 months; adjusted mean difference 1.28, 95% CI 0.31–2.24; p = 0.01; continued: 10.81 ± 1.97 vs. 6.98 ± 4.08 months; adjusted mean difference 2.33, 95% CI 0.13–4.54; p = 0.04). Exploratory dose–response effects indicated that more SSC hours predicted longer exclusive and continued breastfeeding duration. This study demonstrates that for the total group, the 5-week daily SSC intervention did not extend exclusive and continued breastfeeding duration. However, for mothers performing a regular daily hour of SSC, this simple and accessible intervention may extend exclusive and continued breastfeeding duration by months. Future studies are required to confirm these promising findings. Trial registration: Netherlands Trial Register (NTR5697). 相似文献
3.
4.
Dorothy Doughty Janet Ramundo Phyllis Bonham Janice Beitz Paula Erwin-Toth Renee Anderson Bonnie Sue Rolstad 《Journal of wound, ostomy, and continence nursing》2006,33(2):125-30; quiz 131-2
Wound assessment is a key element of effective wound care, and assessment of pressure ulcers includes accurate determination of wound stage. Although the original staging system established by Shea was based on his understanding of the pathology involved in pressure ulcer development, subsequent staging systems (and the one currently in use) were intended simply to establish the level of tissue damage. Recently, clinicians have drawn attention to numerous limitations associated with the current staging system, including the inability to differentiate between an inflammatory response involving intact skin and a deep tissue injury (deep bruising) underneath intact skin. This is a clinically significant difference because clinicians have noted that most inflammatory responses resolve with intervention, whereas most areas of deep tissue injury progress to full-thickness ulcers even when appropriate intervention is provided. A second area of controversy involves partial-thickness (Stage 2) lesions; because many of these lesions are caused by maceration and/or friction (as opposed to pressure) clinicians are frequently unclear regarding which of these lesions should be staged. In response to these concerns, the National Pressure Ulcer Advisory Panel convened a consensus forum and published white papers to clearly outline the issues; they solicited clinician feedback on the white papers and the Wound, Ostomy, Continence Nurses Society provided a written response. This article summarizes the key points of the white papers, WOCN Society response, and consensus forum discussion. 相似文献
5.
Bonnie A Labdi 《American journal of health-system pharmacy》2006,63(21):2053-2054
6.
Amanda Symington RN MHSc Marilyn Ballantyne RN MHSc Janet Pinelli RN MScN Bonnie Stevens RN PhD 《Journal of obstetric, gynecologic, and neonatal nursing : JOGNN / NAACOG》1995,24(4):321-326
Objective: To determine the effect of indwelling versus intermittent feeding tube placement on weight gain, apnea, and bradycardia in premature neonates.
Design: Eligible subjects were assigned randomly to either feeding tube method. Each subject was followed for 6 days.
Setting: The study was conducted in a secondary level neonatal intensive-care unit (NICU), a tertiary level NICU in a perinatal center, and a tertiary level NICU in a referral center.
Patients/Participants: Neonates who were 24–34 weeks gestational age, developmentally appropriate for gestational age, medically stable, on full enteral feedings through an orogastric or a nasogastric tube, and not fluid restricted. Ninety-three neonates were enrolled-49 in the indwelling group and 44 in the intermittent group. Nine neonates did not complete the study.
Interventions: Nasogastric indwelling feeding tubes were placed and left in site for up to 3 days. Orogastric intermittent feeding tubes were placed for each feeding and removed at completion of the feeding.
Main outcome measures: Weight gain, apnea, and bradycardia. Results: Members of both groups had similar demographic characteristics, clinical problems, and nutritional intake. No statistical differences were found between the two groups in weight gain or episodes of apnea and bradycardia.
Conclusions: There were no statistically or clinically significant differences between the two groups. The intermittent method of feeding is more expensive. Because no clinical differences were found, the type of tube placement chosen for feeding the premature infant may be based on economics. 相似文献
Design: Eligible subjects were assigned randomly to either feeding tube method. Each subject was followed for 6 days.
Setting: The study was conducted in a secondary level neonatal intensive-care unit (NICU), a tertiary level NICU in a perinatal center, and a tertiary level NICU in a referral center.
Patients/Participants: Neonates who were 24–34 weeks gestational age, developmentally appropriate for gestational age, medically stable, on full enteral feedings through an orogastric or a nasogastric tube, and not fluid restricted. Ninety-three neonates were enrolled-49 in the indwelling group and 44 in the intermittent group. Nine neonates did not complete the study.
Interventions: Nasogastric indwelling feeding tubes were placed and left in site for up to 3 days. Orogastric intermittent feeding tubes were placed for each feeding and removed at completion of the feeding.
Main outcome measures: Weight gain, apnea, and bradycardia. Results: Members of both groups had similar demographic characteristics, clinical problems, and nutritional intake. No statistical differences were found between the two groups in weight gain or episodes of apnea and bradycardia.
Conclusions: There were no statistically or clinically significant differences between the two groups. The intermittent method of feeding is more expensive. Because no clinical differences were found, the type of tube placement chosen for feeding the premature infant may be based on economics. 相似文献
7.
8.
BACKGROUND: Somatosensory evoked potentials (SSEPs) have long been recognized as an excellent tool for detecting neural and vascular compromise during vascular, neurosurgical and orthopedic procedures. SSEPs have the ability to localize, central versus peripheral, the area of compromise. Many surgeons use only lower-limb SSEP monitoring when performing lumbar spinal surgery. The upper extremities are usually not monitored during such procedures, and monitoring oxygen saturation does not detect neural compromise. PURPOSE: To report that the expanded use of SSEP monitoring during surgery can be beneficial in detecting peripheral ischemia or neural compromise resulting from positioning. STUDY DESIGN: Three case reviews of orthopedic spine surgeries where SSEP monitoring provided early warnings of vascular and neural compression. METHODS: The cases review three different lumbar procedures in which evidence of peripheral ischemia and nerve compression were detected by SSEP monitoring. RESULTS: By the use of upper- and lower-extremity monitoring during lumbar procedures, early detection of ischemia and nerve compression were noted intraoperatively. These changes prompted examination of the patient and repositioning to correct the ischemia or compression. The repositioning in these cases corrected the problem, and no lasting effects were found. CONCLUSIONS: Including SSEP monitoring of the bilateral upper extremities should be considered during lumbar spinal procedures. Such monitoring can be offered for a slightly increased expense and only minimal time delay to place the additional required electrodes by the technician. As a direct result of the early warning of the SSEP monitoring, we were able to avoid potential ischemic injuries and improve patient outcomes. 相似文献
9.
Laura L S Howe Ashton M Anderson David A S Kaufman Bonnie C Sachs David W Loring 《Archives of clinical neuropsychology》2007,22(6):753-761
We prospectively evaluated performance of 63 referrals to a memory disorders clinic who received the Medical Symptom Validity Test (MSVT) as part of their standard neuropsychological evaluation. The patients were grouped based on independent medical diagnoses and presence or absence of a potential financial incentive to under-perform. Twenty-seven patients (42.9%) scored below cutoffs on the MSVT symptom validity indices. Two individuals in the potential financial incentive group showed clear signs of invalid responding (18.2%). Twenty-two of the remaining 25 patients who failed the symptom validity indices corresponded to the dementia profile. Three individuals did not correspond to the dementia profile but are thought to have performed validly representing a 4.8% false positive rate. When considering all MSVT indices, the base rate of invalid responding in the potential financial incentive to under-perform group increased to 27.3%. Combining all groups our base rate of invalid responding was 4.8%. Specific performances are presented. 相似文献
10.