全文获取类型
收费全文 | 2844篇 |
免费 | 391篇 |
国内免费 | 40篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 179篇 |
妇产科学 | 52篇 |
基础医学 | 182篇 |
口腔科学 | 58篇 |
临床医学 | 369篇 |
内科学 | 857篇 |
皮肤病学 | 66篇 |
神经病学 | 288篇 |
特种医学 | 322篇 |
外科学 | 324篇 |
综合类 | 59篇 |
一般理论 | 5篇 |
预防医学 | 139篇 |
眼科学 | 122篇 |
药学 | 104篇 |
中国医学 | 1篇 |
肿瘤学 | 133篇 |
出版年
2023年 | 61篇 |
2022年 | 21篇 |
2021年 | 34篇 |
2020年 | 96篇 |
2019年 | 32篇 |
2018年 | 100篇 |
2017年 | 82篇 |
2016年 | 80篇 |
2015年 | 89篇 |
2014年 | 113篇 |
2013年 | 142篇 |
2012年 | 88篇 |
2011年 | 92篇 |
2010年 | 108篇 |
2009年 | 139篇 |
2008年 | 78篇 |
2007年 | 92篇 |
2006年 | 86篇 |
2005年 | 75篇 |
2004年 | 54篇 |
2003年 | 51篇 |
2002年 | 54篇 |
2001年 | 70篇 |
2000年 | 59篇 |
1999年 | 56篇 |
1998年 | 95篇 |
1997年 | 105篇 |
1996年 | 84篇 |
1995年 | 77篇 |
1994年 | 51篇 |
1993年 | 56篇 |
1992年 | 55篇 |
1991年 | 50篇 |
1990年 | 59篇 |
1989年 | 89篇 |
1988年 | 73篇 |
1987年 | 60篇 |
1986年 | 58篇 |
1985年 | 51篇 |
1984年 | 41篇 |
1983年 | 30篇 |
1982年 | 32篇 |
1981年 | 28篇 |
1980年 | 17篇 |
1979年 | 36篇 |
1978年 | 16篇 |
1977年 | 19篇 |
1976年 | 15篇 |
1971年 | 14篇 |
1969年 | 11篇 |
排序方式: 共有3275条查询结果,搜索用时 15 毫秒
1.
2.
Slowly progressive aphasia without generalized dementia: studies with positron emission tomography 总被引:14,自引:0,他引:14
J B Chawluk M M Mesulam H Hurtig M Kushner S Weintraub A Saykin N Rubin A Alavi M Reivich 《Annals of neurology》1986,19(1):68-74
Slowly progressive aphasia without generalized dementia is a degenerative syndrome selectively affecting dominant hemisphere language areas. We report changes in regional glucose metabolism measured by positron emission tomography in two patients with this condition. Striking abnormalities of glucose utilization in the left cerebral cortex were demonstrated in both patients. The findings of other neurodiagnostic studies were relatively unremarkable. The first patient had a 3-year history of progressive anomia and impaired auditory verbal recall. An electroencephalogram was normal, and computed tomography showed mild left perisylvian atrophy. Positron emission tomography revealed profound hypometabolism in the left temporal regions. The second patient also had a 3-year history of progressive anomia. Electroencephalography, computed tomography, and magnetic resonance imaging scans were normal. Positron emission tomography showed a major reduction in left parietal glucose utilization, with a lesser decrement in left temporal metabolism. Neither patient demonstrated significant contralateral or global abnormalities such as those reported in positron emission tomographic studies of Alzheimer's disease with or without focal clinical features. These observations support the concept of adult-onset progressive aphasia without dementia as a clinical syndrome distinct from Alzheimer's disease. 相似文献
3.
4.
Elizabeth S Hart Marilyn H Kelly Beth Brillante Clara C Chen Navid Ziran Janice S Lee Penelope Feuillan Arabella I Leet Harvey Kushner Pamela G Robey Michael T Collins 《Journal of bone and mineral research》2007,22(9):1468-1474
Most lesions in FD and their attendant functional disability occur within the first decade; 90% of lesions are present by 15 years, and the median age when assistive devices are needed is 7 years. These findings have implications for prognosis and determining the timing and type of therapy. INTRODUCTION: Fibrous dysplasia of bone (FD) is an uncommon skeletal disorder in which normal bone is replaced by abnormal fibro-osseous tissue. Variable amounts of skeletal involvement and disability occur. The age at which lesions are established, the pace at which the disease progresses, if (or when) the disease plateaus, and how these parameters relate to the onset of disability are unknown. To answer these questions, we performed a retrospective analysis of a group of subjects with FD. MATERIALS AND METHODS: One hundred nine subjects with a spectrum of FD were studied for up to 32 years. Disease progression was assessed in serial (99)Tc-MDP bone scans by determining the location and extent of FD lesions using a validated bone scan scoring tool. Physical function and the need for ambulatory aids were assessed. RESULTS: Ninety percent of the total body disease skeletal burden was established by age 15. Disease was established in a region-specific pattern; in the craniofacial region, 90% of the lesions were present by 3.4 yr, in the extremities, 90% were present by 13.7 yr, and in the axial skeleton, 90% were present by 15.5 yr. Twenty-five of 103 subjects eventually needed ambulatory aids. The median age at which assistance was needed was 7 yr (range, 1-43 yr). The median bone scan score for subjects needing assistance was 64.3 (range, 18.6-75) compared with 23.1 (range, 0.5-63.5) in the unassisted subjects (p < 0.0001). Among subjects needing assistance with ambulation, 92% showed this need by 17 yr. CONCLUSIONS: The majority of skeletal lesions and the associated functional disability occur within the first decade of life. The implication is that the window of time for preventative therapies is narrow. Likewise, therapeutic interventions must be tailored to where the patient is in the natural history of the disease (i.e., progressive disease [young] versus established disease [older subjects]). These findings have implications for prognosis, the timing and type of therapy, and the development of trials of new therapies and their interpretation. 相似文献
5.
Margaret J. Harrison Kaysi Eastlick Kushner Karen Benzies Gwen Rempel Cathy Kimak 《分娩》2003,30(2):109-115
ABSTRACT: Background: Increasingly, women seek involvement in decisions about their health care. The purpose of this study was to examine women's experience of, and satisfaction with, their involvement in health care decisions during a high‐risk pregnancy. Methods: Forty‐seven women with hypertension or threatened preterm delivery (including multiple births) were interviewed after the birth of their child. They received prenatal care at home from nurses in a community program or were hospitalized. The in‐depth interviews were audiotaped and transcribed; data were analyzed using constant comparative methods. Results: Women identified an increased feeling of responsibility for the health of their baby and themselves, but differed in choosing active or passive involvement in health care decisions. Women who wanted active involvement achieved it through one of three processes: struggling for, negotiating, or being encouraged. Women who wanted passive involvement and women facing health crises used the process of trusting in the expertise of nurses and physicians. Women were satisfied if the care from health care professionals was congruent with how they wanted to be involved in decision‐making. Conclusions: Although most women want to be actively involved in health decision‐making during a high‐risk pregnancy, some prefer a passive role. The setting of prenatal care, community‐based or in‐hospital, was less important than the ability of nurses and physicians to support the woman in her preferred role in decision‐making. (BIRTH 30:2 June 2003) 相似文献
6.
B J Kushner 《Journal of AAPOS》1997,1(1):55-62
PURPOSE: Inferior oblique anteriorization is gaining popularity for the treatment of dissociated vertical divergence associated with inferior oblique overaction. This procedure is based on the theory that moving the insertion of the inferior oblique muscle anterior to the equator changes its vector of force from one of elevation to one that opposes elevation. The purpose of this investigation is to describe, investigate the cause, and outline treatment for a complication I observed after inferior oblique anteriorization. This postoperative syndrome consists of a motility pattern that resembles marked residual inferior oblique overaction associated with a Y or V pattern. It is probably caused by a restriction of elevation of the abducting eye causing fixation duress, with a resultant upshoot of the contralateral adducting eye. METHODS: A retrospective chart review was conducted for all patients on whom I performed bilateral inferior oblique anteriorization for inferior oblique overaction associated with dissociated vertical divergence. Patients in whom this postoperative syndrome developed were compared with those in whom it did not with respect to type and extent of surgery. In addition, cases of patients I treated or examined for this complication but whose inferior oblique anteriorization had been performed by other ophthalmologists were also analyzed. RESULTS: I performed bilateral inferior oblique anteriorization in 77 patients. In 29 patients the inferior oblique muscles were placed level with the insertions of the inferior rectus muscles, in 31 patients they were placed 1 mm anterior to the insertions of the inferior rectus muscles, and in 17 patients they were placed 2 mm anterior. The postoperative syndrome described here developed in two of the 77 patients; both had the inferior oblique muscles placed 2 mm anterior to the insertions of the inferior rectus muscle. These were also the only two patients in this series in whom the new insertion of the inferior oblique muscle was spread out laterally at the time of anteriorization. I have seen an additional six patients in whom this syndrome developed after undergoing operations by other ophthalmologists. In four, the inferior oblique muscles were placed 2 mm anterior to the insertions of the inferior rectus muscles, and in two they were placed 3 mm anterior. Of the eight patients I have observed with this complication, I reoperated on six. The surgical procedure consisted of denervation or extirpation of both inferior oblique muscles in four patients and conversion to standard recessions of the inferior oblique muscles in two patients. In all six patients,the versions were markedly improved and the Y orV pattern was eliminated after reoperation. CONCLUSIONS: Anteriorization of the inferior oblique muscles more than 1 mm anterior to the insertions of the inferior rectus muscle may cause a limitation of elevation in abduction, resulting in a Y or V pattern that mimics inferior oblique overaction. This may be more likely to occur if the new insertions of the inferior oblique muscles are spread out laterally at the time of anteriorization. 相似文献
7.
Kaysi Eastlick Kushner Margaret J Harrison 《Revue canadienne de recherche en sciences infirmières》2002,34(1):47-65
This critical feminist grounded theory study examined how employed mothers coped with the stress of managing multiple responsibilities in family, health, and paid work. Over a 2-year period, 20 mothers employed as support staff in a large, publicly funded institution participated in repeated individual in-person and telephone interviews and in a focus group. Interviews were transcribed and analyzed using constant comparative methods. The women experienced stress from continuous demands in paid and family health work compounded by time constraints, inflexible expectations, conflicting demands, compromised personal resources, and inadequate support. Most of their coping strategies were individual, such as focusing on priorities, but some women used shared family decision-making. Findings support both individual and family stress and coping theory, yet underscore the need to explicate social-ecological influences such as relational power. Strategies that can enhance coping and reduce stress are described for nurses who work with women and families. 相似文献
8.
9.
D W Jackson D K Pitts R Kushner 《The Journal of the American Osteopathic Association》1990,90(12):1071-1080
An accurate prediction of birth weight during gestation can provide useful information for assessing fetal and newborn health status, enabling the clinician to better predict infant morbidity and mortality. Two previously reported standard methods for birth-weight estimation used data collected in utero to derive formulas by least-squares linear regression. The rationale for the inclusion of particular variables in these equations, however, has not been clearly defined. This study was undertaken to examine the efficacy of some previously used variables as well as some new variables in estimating fetal birth weight. The authors used measurements of femur length, biparietal diameter, and abdominal circumference from 107 fetuses (2500 to 4000 g) as variables to compare the two standard methods of birth-weight estimation. A new formula is presented that is derived from a simple model based on the known relationship between volume and weight. The head is represented as a sphere and the body as a cylinder. This study presents a more systematic approach to formula development in which statistical biases are minimized by examining the underlying distributions of the variables used to predict birth weight. 相似文献
10.