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51.
Poor tendon to bone healing following rotator cuff repair has led to the continued interest and investigation into biological augmentation. The biology of tendinopathy is not fully understood and consequently the availability of disease modifying therapeutic targets is limited. A ceiling of benefit has been reached by mechanical optimisation of rotator cuff repair and thus, in order to improve healing rates, a biological solution is required. This review focuses on the strategies to biologically augment rotator cuff disorders with an emphasis on rotator cuff repair. Leucocyte rich platelet rich plasma has been shown to improve healing rates without clinically relevant improvements in outcome scores. Similarly, improved healing rates have also been reported with bone marrow stimulation and in long-term follow-up with bone marrow concentrate. Extracellular matrix (ECM) and synthetic scaffolds can increase healing through mechanical and or biological augmentation. A potential third category of scaffold is bio-inductive and has no mechanical support. Studies involving various scaffolds have shown promising results for augmentation of large to massive tears and is likely to be most beneficial when tendon quality is poor, however level I evidence is limited.  相似文献   
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《Injury》2021,52(4):686-691
ObjectivesThe purpose of this study was to compare the biomechanical attributes of patella fracture fixation with either anterior plating utilizing two parallel, longitudinal 2.0 mm plates technique versus a cannulated screw tension band technique.MethodsFive matched pairs (ten specimens) of fresh frozen cadavers were utilized. A transverse patella fracture (OTA 34C1.1) was fixed using either two 4.0 mm cannulated screw anterior tension band (CATB) or with two 2.0 mm stainless steel non-locking plates along the anterior cortex secured with 2.4 mm cortical screws traversing the fracture site. Specimens underwent 1000 cycles of simulated active knee range of motion before load to failure destructive testing.ResultsDuring cyclic loading there were no failures in the plate fixation group, and 2 out of 5 specimens catastrophically failed in the CATB group (p = 0.22). Average fracture displacement at the end of fatigue testing was 0.96 mm in the plate fixation group and 2.72 mm in the CATB group (p = 0.18). The specimens that withstood cyclic testing underwent a destructive load. Mean load to failure for the plate fixation specimens was 1286 N, which was not significantly different from the CATB group mean of 1175 N (p = 0.48). The mechanism of failure in the plate fixation cohort was uniformly via a secondary vertical patella fracture around the plates in all five specimens. In the CATB group, the mechanism of failure was via wire elongation and backing out of the screws.ConclusionsPatella fixation with anterior plating technique statistically performed equivalent to cannulated screw anterior tension band in ultimate load to failure strength and fatigue endurance under cyclical loading. No failures were observed cyclic simulated active range of motion in the anterior plate group. There was a trend towards improved fatigue endurance in the plate fixation group, however this did not reach statistical significance. We believe plate fixation technique represents a low-profile implant option for treatment of transverse patella fractures, which may allow for early active range of motion, and these data support biomechanical equivalency to standard of care.  相似文献   
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《Injury》2021,52(6):1569-1576
IntroductionTreatment of complex upper end tibial fractures has always been a challenge to orthopaedic surgeons. Though the roentgenogram results are satisfactory, the clinical and functional outcomes especially in terms of squatting/cross-leg sitting after long term follow-up are little known. Hence, we have done this study with a primary aim to assess the clinico-radiological and functional outcomes after operative fixation (mostly by locking plates) in complex upper end tibial fractures and a secondary aim to analyze correlation between functional outcome scores/range of motion (ROM) and the ability to squat & sit cross-legged in post-operative period.Materials and methodsThis prospective study included a total of 33 patients who were mainly treated with locking plates. In the follow-up, patients were assessed clinico-radiologically and outcome measurements were determined using the Tegner-Lysholm (T-L) Knee Score. Patients were categorized according to their ability to squat/sit cross-legged and a subgroup analysis was performed by comparing mean ROM and T-L score in each group.ResultsMajority of patients were in young and adult age group with a male to female ratio of 4.5:1. The average age was 42.39 ±14.64 years. Road traffic accident was the most common mode of injury. Average time interval between injury and surgery was 5.8±4.4 days. All the fractures united by 5-9 months. Mean ROM and T-L score at last follow-up were 120.94°±13.63° and 88.12±7.24 respectively. Average shortening, varus and valgus deformity were 0.43±0.09 cm, 2.12°±0.62° and 1.06°±0.45° respectively. 14 patients (42.42%) were able to squat and 15 (45.45%) were able to sit cross-legged postoperatively. Upon subgroup analysis, difference of mean ROM in those who could squat/sit cross-legged was found statistically significant (p≤0.05), however the difference in mean functional scores was not significant (p≥0.05).ConclusionComplex upper tibial fractures are a difficult entity to deal with. Anatomical locking plates take care of the alignment, articular congruity as well as ligamentous balancing thus giving good mid-term outcomes after ORIF/MIPO. However, applicability of the present functional outcome scores in assessing squatting/cross leg sitting remains doubtful. More weightage needs to be given to these activities to evaluate the outcome in South Asian population.  相似文献   
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《Injury》2021,52(7):1964-1970
BackgroundAlthough ankle arthroscopy is increasingly used to diagnose syndesmotic instability, precisely where in the incisura one should measure potential changes in tibiofibular space or how much tibiofibular space is indicative of instability, however, remains unclear. The purpose of this study was to determine where within the incisura one should assess coronal plane syndesmotic instability and what degree of tibiofibular space correlates with instability in purely ligamentous syndesmotic injuries under condition of lateral hook stress test (LHT) assessment.MethodsAnkle arthroscopy was performed on 22 cadaveric specimens, first with intact ankle ligaments and then after sequential sectioning of the syndesmotic and deltoid ligaments. At each step, a 100N lateral hook test was applied through a lateral incision 5 cm proximal to the ankle joint and the coronal plane tibiofibular space in the stressed and unstressed states were measured at both anterior and posterior third of the distal tibiofibular joint, using calibrated probes ranging from 0.1 to 6.0 mm, in 0.1 mm of increments. The anterior and posterior points of measurements were defined as the junction between the anterior and middle third, and junction between posterior and middle third of the incisura, respectively.ResultsAnterior third tibiofibular space measurements did not correlate significantly with the degree of syndesmotic instability after transection of the ligaments, neither before nor after applying LHT at all the three groups of different sequences of ligament transection (P range 0.085-0.237). In contrast, posterior third tibiofibular space measurements correlated significantly with the degree of syndesmotic instability after transection of the ligaments, both with and without applying stress in all the groups of different ligament transection (P range <0.001-0.015). Stressed tibiofibular space measurements of the posterior third showed higher sensitivity and specificity when compared to the stressed anterior third measurements. Using 2.7 mm as a cut off for posterior third stressed measurements has both sensitivity and specificity about 70 %.ConclusionSyndesmotic ligament injury results in coronal plane instability of the distal tibiofibular articulation that is readily identified arthroscopically with LHT when measured in the posterior third of the incisura.Clinical relevanceWhen applying LHT, tibiofibular space measurement for coronal plane instability along the anterior third of the incisura is less sensitive for identifying syndesmotic instability and may miss this diagnosis especially when subtle.  相似文献   
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《Injury》2021,52(7):1886-1890
BackgroundTreatment of polytrauma patients with femoral shaft fracture has changed considerably during the past few decades. A transition from early total care (ETC) to “Damage Control” Orthopaedics (DCO) in selected patients was proposed in order to decrease mortality. The aim of the study was to investigate whether this policy change resulted in improved patient outcome.MethodsWe present a retrospective, comparative study, held in a Level I trauma center in Jerusalem, Israel. Polytrauma patients with Injury Severity Score higher than 16 with femoral shaft fracture were included. Data was extracted from our institute's electronic trauma registry. The study examines two time periods: Between the years 1996 and 2006 patients were treated according to the ETC protocol, with immediate intramedullary nailing (IMN) within 12 h. From 2007 until 2019 a DCO policy was adopted, implementing temporary external fixator for high risk patients, according to the “Hannover” criteria. Following resolution of the acute phase, these were converted to IMN. Patients eligible for DCO were matched to controls who received ETC during the earlier period.ResultsA total of ninety-six patients were included (DCO n = 44, ETC n = 52). The groups were comparable in terms of age, gender, mechanism of injury, injury to surgery time and Injury severity score (DCO median 31.5, ETC median 29). No statistical difference was found between the groups in terms of mortality (P = 0.757), acute respiratory distress syndrome (P = 0.534), sepsis (P = 0.519) and hospital stay (DCO median 24 days, ETC median 21.5 days) or ICU stay (Median 7 days in both groups).ConclusionsThis pilot study did not demonstrate better outcome by implementing DCO concepts in the polytrauma patient.Level of evidenceIII prognostic.  相似文献   
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《Injury》2021,52(10):3064-3067
IntroductionCT angiography (CTA) is efficient and accurate in detecting lower limb vascular injury in the setting of trauma (1-6). Less clear is the in-practice correlation between appropriate indications for these examinations and subsequent clinical impacts.Materials and MethodsAll CT leg angiography acquired from January 2016 through April 2019 were reviewed via retrospective search. Studies not acquired for trauma were excluded. Imaging and reports were reviewed to assess for vascular injury. Electronic medical records were reviewed to assess the presence or absence of classical ‘hard’ or ‘soft’ signs of vascular injury and whether vascular intervention was undertaken.ResultsA total of 347 lower limb injuries were identified in 273 men and 74 women. Mean age was 41.5 years ranging from 15-95 years. 268 cases were fractures with 177 open injuries. 301 of injuries were secondary to blunt trauma, 31 penetrating injury occurred and 15 cases were ascribed to blast/gunshot injury.74 (21.3%) studies were deemed to have a positive finding of vascular injury, 249 (71.8%) were reported as negative and 24 (6.9%) were indeterminate. Of the cases with positive findings, 26 underwent intervention (7.4% of all patients undergoing CTA). No patients with negative CTA required intervention, while three (3, 0.8% of total) with indeterminate findings required intervention.Where there were no clinical signs (absence of any hard or soft signs) 249 CTA's were performed and none required any form of intervention.ConclusionIn the absence of clinical signs of vessel injury, CT angiography is unlikely to demonstrate vascular injury requiring intervention in the setting of lower limb trauma.  相似文献   
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《Injury》2021,52(11):3498-3504
PurposeAim of this study was to determine the rate of low-grade infection in patients with primarily as aseptic categorized tibial shaft nonunion and lack of clinical signs of infection.MethodsIn a retrospective study between 2006 and 2013, all patients who underwent revision surgery for treatment of tibial shaft nonunion without clinical evidence of infection were assessed. Bacterial cultures harvested during nonunion revision, C-reactive protein (CRP) and/or white blood cell (WBC) values at hospital admission, outcome, and epidemiological data were analyzed.ResultsIn 88 patients with tibial shaft nonunion without any clinical signs of infection, bacterial samples remained negative in 51 patients. In 37 patients, microbiological diagnostic studies after long-term culturing demonstrated positive bacterial cultures whereas after short-term culturing for 2 days only 17 positive cultures were observed. In 12 cases a mixed culture with 2.3 different bacteria on average was detected. Among patients with negative bacterial cultures bone healing was achieved after 13.2 months. Nonunion with positive bacterial cultures required 19 (range 2-42) months until osseous healing (p = 0.009). Furthermore, nonunion with positive bacterial cultures require statistically more surgical revisions to achieve healing (2.9 ± 0.5 vs. 1.3 ± 0.1 additional procedure; (p = 0.003). Hematological studies carried out before surgical intervention did not demonstrate significant differences in CRP values (negative vs. positive cultures: 0.3 (range 0.3-2.8) mg/dl vs. 0.5 (range 0.3-5.7) mg/dl (p = 0.181) and in WBC values (negative vs. positive cultures: 7.4 (range 3.5-11.9) /nl vs. 7.3 (range 3.7-11.1) /nl (p = 0.723). Limitations of this study may include the varying amount of the at least four samples for microbiological diagnostics as well as the circumstance that for diagnosing low-grade infection swabs and tissue samples were included in this evaluation as being equivalent.ConclusionThe pathogenesis of nonunion may originate from low-grade infection even in patients without clinical signs of infection. In addition, nonunion with positive bacterial cultures require statistically more surgical revisions to achieve healing. Therefore, during any revision surgery, multiple bacterial samples are intended to be harvested for long-term culturing. Particularly, in tibial shaft nonunion following Gustilo-Anderson type III open fractures, low-grade infection should be suspected.Trial registration numberDRKS00014657.Date of registration04/26/2018 retrospectively registered  相似文献   
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