全文获取类型
收费全文 | 571篇 |
免费 | 37篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 47篇 |
妇产科学 | 8篇 |
基础医学 | 57篇 |
口腔科学 | 14篇 |
临床医学 | 89篇 |
内科学 | 120篇 |
皮肤病学 | 3篇 |
神经病学 | 63篇 |
特种医学 | 12篇 |
外科学 | 41篇 |
预防医学 | 66篇 |
眼科学 | 15篇 |
药学 | 36篇 |
肿瘤学 | 33篇 |
出版年
2023年 | 3篇 |
2022年 | 7篇 |
2021年 | 17篇 |
2020年 | 13篇 |
2019年 | 12篇 |
2018年 | 16篇 |
2017年 | 11篇 |
2016年 | 19篇 |
2015年 | 14篇 |
2014年 | 19篇 |
2013年 | 28篇 |
2012年 | 47篇 |
2011年 | 43篇 |
2010年 | 22篇 |
2009年 | 14篇 |
2008年 | 30篇 |
2007年 | 42篇 |
2006年 | 31篇 |
2005年 | 22篇 |
2004年 | 35篇 |
2003年 | 20篇 |
2002年 | 11篇 |
2001年 | 7篇 |
2000年 | 5篇 |
1999年 | 4篇 |
1998年 | 4篇 |
1997年 | 4篇 |
1996年 | 6篇 |
1995年 | 5篇 |
1994年 | 8篇 |
1993年 | 3篇 |
1992年 | 8篇 |
1991年 | 6篇 |
1990年 | 2篇 |
1989年 | 6篇 |
1988年 | 5篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1985年 | 7篇 |
1984年 | 7篇 |
1983年 | 2篇 |
1982年 | 6篇 |
1979年 | 5篇 |
1977年 | 2篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1973年 | 3篇 |
1972年 | 6篇 |
1971年 | 2篇 |
1962年 | 1篇 |
排序方式: 共有611条查询结果,搜索用时 0 毫秒
1.
2.
P Christensson M Arborelius R Kautto-Wiberg 《Respiration; international review of thoracic diseases》1986,49(1):16-22
We studied the volume of trapped gas (VTG), using a nitrogen washout method, before and after bronchodilation in four groups with theoretically increasing risk of developing pulmonary emphysema: (1) nonsmoking healthy controls (PiMn), (2) nonsmoking subjects with an intermediate alpha 1-antitrypsin deficiency (PiMZn), (3) smoking subjects with normal concentration of alpha 1-antitrypsin, and (4) smoking PiMZ subjects. VTG was the only lung function variable that showed a significant difference between PiMZn and PiMn subjects but only after bronchodilation. Some conventional lung function tests also distinguished smokers from nonsmokers of both genotypes but VTG was the most sensitive test. VTG decreased after salbutamol inhalation in the control group but showed a consecutively larger increase with more risk factors of developing emphysema. An increase in VTG after bronchodilation may be a sign of alveolar abnormality preceding development of clinical lung emphysema. 相似文献
3.
Miodrag Palfi Lotta Martinsson Kristina Sundstr?m 《Transfusion and apheresis science》2007,36(3):291-295
BACKGROUND: The aim of this study was to find an effective treatment for hypocalcemic symptoms during plateletpheresis and to evaluate if a combination of calcium, magnesium and vitamin D3 is more effective in comparison to routine calcium supplementation. MATERIAL AND METHODS: A study group consisting of 10 donors, having a history of previous hypocalcemic symptoms during plateletpheresis, donated platelets twice in a one-month period. During the first donation combination tablets (600mg Ca+300mg Mg+100IU vitamin D3) were used to treat hypocalcemic symptoms while routine treatment calcium carbonate tablets (1000mg Ca) were used during the second donation. If symptoms persisted after 10min the same dose was repeated. A control group, with no supplementation, consisting of five donors, with no history of hypocalcemic symptoms, were included. Donor subjective symptoms were graded and recorded on four occasions: at the start of plateletpheresis, when symptoms appeared, 10min after the first tablet and at the end of donation. Samples for analysis of ionized calcium (iCa), magnesium and potassium were also taken at the same occasions. RESULTS: All donors from the study group experienced minor or medium hypocalcemic symptoms and needed a second dose of supplementation. Calcium carbonate tablets completely relieved the hypocalcemic symptoms in six donors, it had no effect on three donors and one donor experienced aggravated symptoms. The combination tablets completely relieved the symptoms in three donors, one donor experienced a partial relief and six donors had no relief of symptoms. There were no significant differences in iCa, potassium and magnesium levels were noted in the study group irrespective of which tablets were used for treatment of hypocalcemic symptoms. After plateletpheresis the median iCa levels declined by 30% and potassium levels declined by 3-11% in all donors while the magnesium levels were not significantly affected. There was no correlation between the presence of symptoms and the changed levels of iCa or magnesium. CONCLUSION: Addition of magnesium and vitamin D3 to calcium seems to have no beneficial effect in the treatment of hypocalcemic symptoms in plateletpheresis donors. 相似文献
4.
Ventilatory efficiency for eliminating CO2 is expressed by the physiological dead space, VD phys = (1-PE CO2/Pa CO2) x VT, where PE is the mixed exhaled and Pa the arterial CO2-tension and VT the tidal volume. We used data from the multiple breath N2-wash-out with oxygen for calculating a functional dead space for nitrogen. VDF N2 = (1-FEN2/FidN2) x VT.FEN2 is the mixed exhaled N2-fraction and FidN2 the calculated mean alveolar N2-fraction during a wash-out with the same number of breaths to reach 2% N2 in end tidal air, but having completely even distribution. FidN2 is shown to be 0.20 +/- 0.01 for wash-outs using 20-150 breaths. The method was applied to wash-outs from 21 healthy volunteers, 18 patients with chronic obstructive lung disease and two subjects with acute bronchospasm. VDF was well related to VD phys CO2 (r = 0.78) but higher than the latter. In subjects with lung disease VDF was inversely related to the degree of obstruction expressed by forced expiratory volume in one second per cent of vital capacity (r = 0.85). The subjects with bronchospasm had very high VD/VTF in relation to their FEV%. If airway dead space predicted from height and sex is subtracted from VDF, the resulting alveolar dead space will be a good expression for uneven gas distribution in the lungs. We also deduced a direct mathematical relation between lung clearance index and VD/VTF. The documented good reproducibility of LCI is thus also valid for VD/VTF, while the latter better expresses ventilatory efficiency. 相似文献
5.
Functional and alveolar dead spaces for nitrogen (VDF and VDalv) were calculated in a population of 20 male and 20 female heavy smokers and compared to data from static and forced spirometry (functional residual capacity [FRC], residual volume [RV], lung clearance index [LCI] and volume of trapped gas [VTG]) obtained with the same multiple-breath nitrogen wash-out as the dead spaces, and to variables considered sensitive to small airways disease measured with a single-breath nitrogen elimination (closing volume in per cent of vital capacity [CV%], closing capacity in per cent of total lung capacity [CC%] and slope index [SI]). Both nitrogen dead spaces increased with tidal volume in smokers as well as in healthy non-smokers. The majority of smokers were outside the predicted mean +2 SD for VTG (75%), CC and VDalv (70%) and SI (65%). The following variables were less sensitive for disclosing abnormality: CV (55%), RV (53%), LCI (38%) and forced expired volume in the first second (FEV1, 33%). If high sensitivity is considered preferable in epidemiological studies, the nitrogen dead spaces are equally as sensitive as the better of earlier described tests, and significantly superior to LCI and FEV1. Being tests that measure alveolar distribution of inhaled gas, they are probably sensitive to small airways disease. 相似文献
6.
Hamari Lotta Konttila Jenni Merikukka Marko Tuomikoski Anna-Maria Kouvonen Petra Kurki Marjo 《Journal of immigrant and minority health / Center for Minority Public Health》2022,24(2):506-525
Journal of Immigrant and Minority Health - Parental support is of paramount importance in the promotion of positive parenting, strengthening parenthood and protecting children from disadvantages... 相似文献
7.
8.
9.
Protocol for digital intervention for effective health promotion of small children—A cluster randomized trial
下载免费PDF全文
![点击此处可从《Journal of advanced nursing》网站下载免费的PDF全文](/ch/ext_images/free.gif)
10.
Lotta Saarnio MSc RN Anne‐Marie Boström RN PhD Petter Gustavsson PhD Joakim Öhlén PhD RN 《Scandinavian journal of caring sciences》2016,30(2):312-319
Maintaining the well‐being of older people who are approaching the end‐of‐life has been recognised as a significant aspect of well‐being in general. However, there are few studies that have explicitly focused on at‐homeness among older people. This study aims to illuminate meanings of at‐homeness among older people with advancing illnesses. Twenty men and women, aged 85 or older, with advancing illnesses and who lived in their own homes, in nursing homes or in short‐term nursing homes in three urban areas of Sweden were strategically sampled in the study. Data were generated in narrative interviews, and the analysis was based on a phenomenological hermeneutical method. After obtaining a naïve understanding and conducting structural analyses, two aspects of the phenomenon were revealed: at‐homeness as being oneself and at‐homeness as being connected. At‐homeness as being oneself meant being able to manage ordinary everyday life as well as being beneficial to one's life. At‐homeness as being connected meant being close to significant others, being in affirming friendships and being in safe dependency. Here, at‐homeness is seen as a twofold phenomenon, where being oneself and being connected are interrelated aspects. Being oneself and being connected are further interpreted by means of the concepts of agency and communion, which have been theorised as two main forces of the human being. 相似文献