全文获取类型
收费全文 | 219篇 |
免费 | 13篇 |
国内免费 | 4篇 |
专业分类
儿科学 | 22篇 |
妇产科学 | 2篇 |
基础医学 | 18篇 |
口腔科学 | 2篇 |
临床医学 | 16篇 |
内科学 | 47篇 |
皮肤病学 | 2篇 |
神经病学 | 5篇 |
特种医学 | 83篇 |
外科学 | 14篇 |
综合类 | 5篇 |
预防医学 | 4篇 |
药学 | 9篇 |
肿瘤学 | 7篇 |
出版年
2022年 | 1篇 |
2021年 | 1篇 |
2020年 | 1篇 |
2019年 | 6篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2016年 | 2篇 |
2015年 | 1篇 |
2014年 | 2篇 |
2013年 | 6篇 |
2012年 | 1篇 |
2011年 | 1篇 |
2010年 | 5篇 |
2009年 | 9篇 |
2008年 | 1篇 |
2007年 | 5篇 |
2006年 | 3篇 |
2004年 | 1篇 |
2003年 | 2篇 |
2002年 | 2篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 15篇 |
1997年 | 14篇 |
1996年 | 16篇 |
1995年 | 6篇 |
1994年 | 9篇 |
1993年 | 11篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 5篇 |
1989年 | 12篇 |
1988年 | 10篇 |
1987年 | 9篇 |
1986年 | 9篇 |
1985年 | 11篇 |
1984年 | 3篇 |
1983年 | 6篇 |
1982年 | 9篇 |
1981年 | 1篇 |
1980年 | 4篇 |
1979年 | 4篇 |
1978年 | 6篇 |
1977年 | 4篇 |
1976年 | 3篇 |
1975年 | 3篇 |
1960年 | 1篇 |
1939年 | 1篇 |
1937年 | 1篇 |
排序方式: 共有236条查询结果,搜索用时 15 毫秒
81.
Fracture Repair in the Distal Radius in Postmenopausal Women: A Follow‐Up 2 Years Postfracture Using HRpQCT 下载免费PDF全文
Joost JA de Jong Frans L Heyer Jacobus JC Arts Martijn Poeze András P Keszei Paul C Willems Bert van Rietbergen Piet P Geusens Joop PW van den Bergh 《Journal of bone and mineral research》2016,31(5):1114-1122
Fracture healing is characterized by an intense increase in modeling and remodeling of bone, which allows removal of the cast after a stable distal radius fracture within 3 to 5 weeks. However, at that time, bone strength has not recovered yet. We studied the changes in bone mineral density (BMD), microarchitecture, and bone stiffness after a distal radius fracture during a 2‐year follow‐up in comparison to the contralateral side and the association between the 2‐year stiffness and baseline BMD, microarchitecture, and early changes in these parameters. The fractured side of 14 postmenopausal women (mean age 64 ± 8 years) with a conservatively treated distal radius fracture was scanned by high‐resolution peripheral quantitative computed tomography (HRpQCT) at 1 to 2, 3 to 4, 6 to 8, and 12 weeks and 2 years postfracture. The same region contralaterally was scanned as well at the 2‐year visit. BMD, microarchitecture, and stiffness parameters were determined and the fracture side was compared with the contralateral side using a linear mixed‐effect model. Spearman's correlation was used to correlate the 2‐year bone stiffness with baseline BMD, microarchitecture, and early 3‐month changes in these parameters. Two years postfracture, cortical and trabecular thickness and torsional and bending stiffness were significantly higher at the fractured side compared with the nonfractured side (21%, 55%, 31%, and 29%, respectively, p < 0.05), whereas BMD was similar. Two‐year torsional and bending stiffness correlated significantly with baseline BMD and cortical perimeter (|rho| ≥ 0.63, p < 0.016) but not with early changes in bone parameters. Using HRpQCT, this study illustrates that fracture healing is not completed by the time the cast is removed. We showed that from 6 weeks to 2 years postfracture, large changes occur in BMD, microarchitecture, and biomechanical parameters at the fractured side, which were fully recovered after 2 years in comparison to the nonfractured contralateral side. Interestingly, higher 2‐year torsional and bending stiffness were associated with lower BMD and higher cortical perimeter at baseline. © 2015 American Society for Bone and Mineral Research. 相似文献
82.
Daniel I. Sessler Joshua A. Bloomstone Solomon Aronson Colin Berry Tong J. Gan John A. Kellum James Plumb Monty G. Mythen Michael P.W. Grocott Mark R. Edwards Timothy E. Miller Timothy E. Miller Monty G. Mythen Michael PW. Grocott Mark R. Edwards 《British journal of anaesthesia》2019,122(5):563-574
Background
Intraoperative mortality is now rare, but death within 30 days of surgery remains surprisingly common. Perioperative myocardial infarction is associated with a remarkably high mortality. There are strong associations between hypotension and myocardial injury, myocardial infarction, renal injury, and death. Perioperative arterial blood pressure management was thus the basis of a Perioperative Quality Initiative consensus-building conference held in London in July 2017.Methods
The meeting featured a modified Delphi process in which groups addressed various aspects of perioperative arterial pressure.Results
Three consensus statements on intraoperative blood pressure were established. 1) Intraoperative mean arterial pressures below 60–70 mm Hg are associated with myocardial injury, acute kidney injury, and death. Injury is a function of hypotension severity and duration. 2) For adult non-cardiac surgical patients, there is insufficient evidence to recommend a general upper limit of arterial pressure at which therapy should be initiated, although pressures above 160 mm Hg have been associated with myocardial injury and infarction. 3) During cardiac surgery, intraoperative systolic arterial pressure above 140 mm Hg is associated with increased 30 day mortality. Injury is a function of arterial pressure severity and duration.Conclusions
There is increasing evidence that even brief durations of systolic arterial pressure <100 mm Hg and mean arterial pressure <60–70 mm Hg are harmful during non-cardiac surgery. 相似文献83.
The distal femoral epiphyseal ossification center in the assessment of third-trimester menstrual age: sonographic identification and measurement 总被引:1,自引:0,他引:1
The distal femoral epiphyseal secondary ossification center (DFE), which can be reliably identified and measured sonographically, may assist the sonologist in predicting third-trimester menstrual age. Between 28 and 35 menstrual weeks, the percentage of fetuses with a DFE progressively increases. Although the mean age at DFE appearance is approximately 32-33 menstrual weeks, the DFE may be seen as early as 29 menstrual weeks. Nevertheless, the age of a fetus without an identifiable DFE is most likely less than or equal to 34 menstrual weeks. Measurements of the DFE show that its size increases linearly: the menstrual age of a fetus whose DFE measures greater than or equal to 7mm is most likely greater than or equal to 37 weeks. 相似文献
84.
The CD45R and CDw29 antigens are expressed on naive and primed helper T cell populations which serve suppressor-inducer or helper-inducer functions, respectively. These antigens may also be expressed on epithelial cell subpopulations. In the present study, monoclonal antibodies reacting with T lymphocytes and Langerhans cells (LC) were used to characterize the expression of CD45R and CDw29 antigens in oral lichen planus. CDw29 was expressed by LC and lymphocytic cells whereas keratinocyte reactivity varied from negative through to full thickness staining. Expression of CD45R was confined to intraepithelial cells with either lymphocytic or dendritic morphology. A relatively constant ratio of CD1a + LC to CD45R + cells (2:1) was seen. These results demonstrate the existence of intraepithelial cells expressing antigens which are functionally important in T cell responses and which may provide local immunoregulatory influences. 相似文献
85.
86.
87.
We attempted to use hand-held, high-resolution breast sonography to localize for biopsy 11 solid, nonpalpable lesions detected by mammography. Using sonography, we identified and localized only one of four lesions presenting as poorly defined masses and only one of seven lesions presenting as clusters of tiny calcifications. This 18% rate of success is too low to justify the use of sonography for all patients undergoing needle localization. Mammography remains the procedure of choice for localizing solid, nonpalpable breast masses and clustered calcifications. 相似文献
88.
金艾康合并化学药物治疗肿瘤临床疗效观察 总被引:4,自引:2,他引:2
目的:探讨金艾康(汉防己甲素片)合用化学药物治疗肿瘤的临床增效作用。方法:通过比较治疗组与对照组(金艾康合并化学药物者为治疗组,单用化学药物者为对照组,每组各为30例)的总缓解率与毒副反应来评价金艾康对化疗药物的增效作用。结果:治疗组与对照组的总缓解率分别为80%与66.7%,其中部分毒副反应如消化道反应与肢端订木症状等治疗组明显低于对照组。结论:金艾康具有对化学药物治疗肿瘤增效作用,其作用机理可 相似文献
89.
Seventeen cases of an aberrant sheet of tissue in the amniotic cavity are described to expand and clarify previous observations of this entity. The sheet of tissue demonstrates a thickened base and a free edge that undulates. The fetus moves freely about the sheet of tissue. There are no associated fetal deformities, and infants have no manifestations of the amniotic-band syndrome. Evidence suggests that these sheets may originate from "wrapping" of the amniochorionic membrane over a uterine synechia. These benign sheets of tissue should not be confused with the amniotic-band syndrome. 相似文献
90.
Cystic retroperitoneal lymphangioma in infants and children 总被引:2,自引:0,他引:2