全文获取类型
收费全文 | 9239篇 |
免费 | 631篇 |
国内免费 | 30篇 |
专业分类
耳鼻咽喉 | 61篇 |
儿科学 | 306篇 |
妇产科学 | 256篇 |
基础医学 | 1347篇 |
口腔科学 | 158篇 |
临床医学 | 1073篇 |
内科学 | 1883篇 |
皮肤病学 | 272篇 |
神经病学 | 1042篇 |
特种医学 | 178篇 |
外科学 | 892篇 |
综合类 | 36篇 |
一般理论 | 10篇 |
预防医学 | 951篇 |
眼科学 | 150篇 |
药学 | 522篇 |
中国医学 | 18篇 |
肿瘤学 | 745篇 |
出版年
2024年 | 10篇 |
2023年 | 90篇 |
2022年 | 165篇 |
2021年 | 378篇 |
2020年 | 235篇 |
2019年 | 323篇 |
2018年 | 384篇 |
2017年 | 268篇 |
2016年 | 282篇 |
2015年 | 286篇 |
2014年 | 444篇 |
2013年 | 554篇 |
2012年 | 829篇 |
2011年 | 766篇 |
2010年 | 404篇 |
2009年 | 361篇 |
2008年 | 524篇 |
2007年 | 620篇 |
2006年 | 572篇 |
2005年 | 541篇 |
2004年 | 460篇 |
2003年 | 367篇 |
2002年 | 357篇 |
2001年 | 42篇 |
2000年 | 40篇 |
1999年 | 52篇 |
1998年 | 67篇 |
1997年 | 50篇 |
1996年 | 41篇 |
1995年 | 33篇 |
1994年 | 36篇 |
1993年 | 25篇 |
1992年 | 26篇 |
1991年 | 10篇 |
1990年 | 14篇 |
1989年 | 14篇 |
1988年 | 10篇 |
1987年 | 6篇 |
1986年 | 18篇 |
1985年 | 12篇 |
1984年 | 11篇 |
1983年 | 18篇 |
1982年 | 13篇 |
1981年 | 8篇 |
1980年 | 15篇 |
1978年 | 6篇 |
1977年 | 8篇 |
1975年 | 6篇 |
1970年 | 7篇 |
1933年 | 7篇 |
排序方式: 共有9900条查询结果,搜索用时 31 毫秒
71.
de Luis E Bilbao JI de Ciércoles JA Martínez-Cuesta A de Martino Rodríguez A Lozano MD 《Cardiovascular and interventional radiology》2008,31(2):367-376
HepaSphere is a new spherical embolic material developed in a dry state that absorbs fluids and adapts to the vessel wall,
leaving no space between the particle and the arterial wall. The aim of this study was to elucidate the final in vivo size,
deformation, final location, and main properties of the particles when reconstituted with two different contrast media (Iodixanol
and Ioxaglate) in an animal model. Two sizes of “dry-state” particles (50–100 and 150–200 μm) were reconstituted using both
ionic and nonionic contrast media. The mixture was used to partly embolize both kidneys in an animal model (14 pigs). The
animals were sacrificed 4 weeks after the procedure and the samples processed. The final size of the particles was 230.2 ± 62.5 μm
for the 50- to 100-μm dry-state particles and 314.4 ± 71 μm for the 150- to 200-μm dry-state particles. When the contrast
medium (ionic versus nonionic) used for the reconstitution was studied to compare (Student’s t-test) the final size of the particles, no differences were found (p > 0.05). The mean in vivo deformation for HepaSphere was 17.1% ± 12.3%. No differences (p > 0.05) were found in the deformation of the particle regarding the dry-state size or the contrast medium (Mann-Whitney test).
We conclude that HepaSphere is stable, occludes perfectly, and morphologically adapts to the vessel lumen of the arteries
embolized. There is no recanalization of the arteries 4 weeks after embolization. Its final in vivo size is predictable and
the particle has the same properties in terms of size and deformation with the two different contrast media (Iodixanol and
Ioxaglate). 相似文献
72.
Schepers T Ginai AZ Van Lieshout EM Patka P 《Archives of orthopaedic and trauma surgery》2008,128(10):1099-1106
Introduction Extra-articular calcaneal fractures represent 25–40% of all calcaneal fractures and an even higher percentage of up to 60%
is seen in children. A disproportionately small part of the literature on calcaneal fractures involves the extra-articular
type. The aim of this study was to investigate the incidence of extra-articular calcaneal fractures in a Level 1 trauma centre,
define the distribution of the various types of fractures and compare patient demographics between extra- and intra-articular
calcaneal fractures. In addition the literature was reviewed for the most common types of extra-articular calcaneal fractures
with regard to incidence, treatment and clinical outcome.
Methods The radiological records between 2003 and 2005 were reviewed for intra- and extra-articular calcaneal fractures. Patient gender-distribution
and age were compared. A literature search was conducted for the treatment of extra-articular calcaneal fractures.
Results In this 3-year study period a total of 49 patients with 50 extra-articular calcaneal fractures and 91 patients with 101 intra-articular
fractures were identified. The median age for the first group was 32.7 years, and for the second group 40.3 years; P = 0.04. Male predominance was significantly less pronounced for extra-articular (63%) compared with intra-articular fractures
(79%; P = 0.04).
Conclusion One-third of all calcaneal fractures are extra-articular. Significant differences exist between the intra- and extra-articular
groups, in terms of lower age and male–female ratio. The literature study shows inconsistencies in treatment options, but
most extra-articular fractures are well manageable conservatively. 相似文献
73.
74.
Postoperative pain is now a critical focus of perioperative patient care. The current perioperative analgesic strategy is a "balanced-multimodal analgesia". Cornerstones of this treatment approach are patient controlled neuraxial administration of local anesthetics and opioids or patient controlled intravenous administration of opioids. However, systemic opioids are limited by side effects. Thus, adjuvants like anticonvulsants, NMDA receptor antagonists, alpha-2 adrenergic agonists and other non-Opioid analgesics are considered to reduce pain and opioid requirements in the perioperative period. In the present review we discuss recent findings about the effectiveness of different systemic administered adjuvants including ketamine, lidocaine, gabapentin, pregabalin and corticosteroids for postoperative pain treatment. Furthermore a nurse based oral analgesic concept using controlled released Oxycodon for all postoperative patients without a patient controlled analgesia device will be introduced. 相似文献
75.
Martínez Aguilar E Acín F March JR Medina FJ de Haro J Flórez A 《Cirugía espa?ola》2007,82(6):321-327
We performed a systematic review of the literature on the diagnosis and treatment of secondary aortoenteric fistulas (AEF). A MEDLINE search was performed of articles published in English or Spanish between January 1991 and August 2006. Diagnostic methods, treatment modalities and the results of surgical treatment were analyzed. The most frequent first aortic surgery associated with AEF was repair of abdominal aortic aneurysm (54.31%). The most common form of presentation was gastrointestinal bleeding. Repair through in situ prosthetic replacement had the lowest early mortality rates (8-13.3%) compared with graft excision and extraanatomic revascularization (18.2-44%). AEF is a serious entity and diagnosis requires a high index of suspicion based on clinical findings and indirect data from imaging techniques (computed tomography). The most appropriate therapeutic option continues to be controversial. 相似文献
76.
Esther M Briganti Rory Wolfe Graeme R Russ Josette M Eris Rowan G Walker John J McNeil 《Nephrology, dialysis, transplantation》2002,17(6):1099-1104
BACKGROUND: Assessment of centre variation in renal transplantation outcome provides an opportunity to examine differences in quality of care between centres. However, differences in outcome may represent differences in patient factors between centres and be biased by sampling variability and inadequate data ascertainment. METHODS: Differences in 12-month graft survival in 1986 primary renal transplant adult recipients from 16 centres in Australia between 1993 and 1998 were examined. Fifteen recipient and donor factors known prior to transplantation were examined to determine factors independently predictive of graft survival. Differences between centres in these factors were examined. Unadjusted and multivariable adjusted outcomes for each centre were compared to the average for all centres. Multivariable hierarchical modelling was employed to account for potential bias due to sampling variability. RESULTS: Factors predictive of reduced 12-month graft survival on multivariable analysis that were significantly different between centres were time on dialysis prior to transplantation, donor age, organ source, and number of human lymphocyte antigen mismatches. Unadjusted 12-month graft survival for all centres was 91.7% and ranged from 83.1 to 96.4%. Although two centres performed significantly lower than average, this poorer outcome was accounted for in one of these two centres after adjusting for factors shown to be independently predictive of outcome. However, multivariable hierarchical modelling failed to identify any centre as performing significantly different to average, with 12-month graft survival ranging from 89.2 to 92.2%. Outcome in patients excluded from the study due to inadequate data ascertainment was significantly worse than patients who were included. CONCLUSIONS: There was no evidence of centre variation after accounting for variation in risk factors predictive of poor outcome between centres, as well as potential bias due to sampling variability. Exclusion of patients due to inadequate data remains an important source of bias in estimating accurate outcomes. Appropriate analytical strategies and consideration of sources of bias are important for the valid identification of centres with poorer outcomes. 相似文献
77.
Influence of different approaches to the cerebellopontine angle on the function of the intermediate nerve 总被引:1,自引:0,他引:1
Stripf T Braun K Gouveris H Stripf EA Mann WJ Amedee RG 《Journal of neurosurgery》2007,107(5):927-931
OBJECT: Surgery in the cerebellopontine angle (CPA) is a standard procedure at many centers. Outcome is focused mainly on preservation of hearing and facial function postoperatively. The nonmotor part of the facial nerve, the intermediate nerve, is nearly neglected nowadays. METHODS: A retrospective study was designed, including a questionnaire that was sent to 178 patients who had undergone surgery between 2000 and 2004. Data were obtained in 156 cases. The questionnaire was divided into five parts assessing the presence of increased tearing, reduced tearing, salivation disturbances, increased nasal secretions, and abnormalities in taste. Finally, a self-assessment of patient symptoms was analyzed. RESULTS: Postoperatively, 70 patients (45%) experienced crocodile tears, whereas 62 (40%) had dry eyes. Disturbances in taste were noted in six patients (4%) preoperatively and in 52 patients (33%) after surgery. Increased nasal secretion was noted in 68 patients (44%) postoperatively. An analysis of the correlation between the surgical approach used and disturbances in the intermediate nerve revealed a strong tendency to a higher rate of symptoms following the middle fossa approach (p = 0.071, chi-square test). CONCLUSIONS: Data in this study demonstrate the clinical importance of nonmotor defects associated with CPA tumor removal. More than 50% of the patients in this study reported postoperative crocodile tears, dry eyes, nasal secretions, and/or taste disturbances. These sequelae may affect both short- and long-term postoperative quality of life to the same extent as deafness or transient facial paresis. The risk of injury seems to be higher after the middle fossa approach. 相似文献
78.
BACKGROUND: We sought to determine the major factors affecting speech production of Cantonese-speaking glossectomized patients. Error pattern was analyzed. METHODS: Forty-one Cantonese-speaking subjects who had undergone glossectomy > or = 6 months previously were recruited. Speech production evaluation included (1) phonetic error analysis in nonsense syllable; (2) speech intelligibility in sentences evaluated by naive listeners; (3) overall speech intelligibility in conversation evaluated by experienced speech therapists. RESULTS: Patients receiving adjuvant radiotherapy had significantly poorer segmental and connected speech production. Total or subtotal glossectomy also resulted in poor speech outcomes. Patients having free flap reconstruction showed the best speech outcomes. Patients without lymph node metastasis had significantly better speech scores when compared with patients with lymph node metastasis. Initial consonant production had the worst scores, while vowel production was the least affected. CONCLUSION: Speech outcomes of Cantonese-speaking glossectomized patients depended on the severity of the disease. Initial consonants had the greatest effect on speech intelligibility. 相似文献
79.
Schepers T Kieboom BC Bessems GH Vogels LM van Lieshout EM Patka P 《Strategies in trauma and limb reconstruction (Online)》2010,5(2):97-103
Depending upon initial treatment, between 2 and 30% of patients with a displaced intra-articular calcaneal fracture require
a secondary arthrodesis. The aim of this study was to investigate the effect of subtalar versus triple arthrodesis on functional
outcome. A total of 33 patients with 37 secondary arthrodeses (17 subtalar and 20 triple) with a median follow-up of 116 months
were asked to complete questionnaires regarding disease-specific functional outcome (Maryland Foot Score, MFS), quality of
life (SF-36) and overall satisfaction with the treatment (Visual Analogue Scale, VAS). Patient groups were comparable considering
median age at fracture, initial treatment (conservative or operative), time to arthrodesis, median follow-up, and post-arthrodesis
radiographic angles. The MFS score was similar after subtalar versus triple arthrodesis (59 vs. 56 points; P = 0.79). No statistically significant difference was found for the SF-36 (84 vs. 83 points; P = 0.67) and the VAS (5 vs. 6; P = 0.21). Smoking was statistically significantly associated with a non-union (χ2 = 6.60, P = 0.017). The current study suggests that there is no significant difference in functional outcome between an in situ subtalar
or triple arthrodesis as a salvage technique for symptomatic arthrosis after an intra-articular calcaneal fracture. Smoking
is a risk factor for non-union. 相似文献
80.
Reduced tonicity stimulates an inflammatory response in nucleus pulposus tissue that can be limited by a COX‐2‐specific inhibitor 下载免费PDF全文
Bart van Dijk Esther Potier Maarten van DIjk Marloes Langelaan Nicole Papen‐Botterhuis Keita Ito 《Journal of orthopaedic research》2015,33(11):1724-1731
In intervertebral disc herniation with nucleus pulposus (NP) extrusion, the elicited inflammatory response is considered a key pain mechanism. However, inflammatory cytokines are reported in extruded herniated tissue, even before monocyte infiltration, suggesting that the tissue itself initiates the inflammation. Since herniated tissue swells, we investigated whether this simple mechanobiological stimulus alone could provoke an inflammatory response that could cause pain. Furthermore, we investigated whether sustained‐release cyclooxygenase‐2 (COX2) inhibitor would be beneficial in such conditions. Healthy bovine NP explants were allowed to swell freely or confined. The swelling explants were treated with Celecoxib, applied either as a bolus or in sustained‐release. Swelling explants produced elevated levels of interleukin‐6 (IL‐6) and prostaglandin E2 (PGE2) for 28 days, while confined explants did not. Both a high concentration bolus and 10 times lower concentration in sustained release completely inhibited PGE2 production, but did not affect IL‐6 production. Swelling of NP tissue, without the inflammatory system response, can trigger cytokine production and Celecoxib, even in bolus form, may be useful for pain control in extruded disc herniation. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1724–1731, 2015. 相似文献