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991.
992.
目的探讨分析外侧半月板体部层裂或纵向撕裂在关节镜下使用AR缝合枪全内垂直褥式缝合的临床疗效。方法本研究回顾性分析2017年1月至2017年12月,我科收治膝关节单纯外侧半月板体部撕裂(层裂或纵向撕裂)36例患者的临床资料,男13例,女23例;年龄16-41岁,平均(26.50±2.50)岁。36例患者中盘状半月板损伤7例。术中将撕裂外侧半月板修切白区内缘,保留红白区交界,体部层裂或纵裂新鲜化处理后行AR缝合枪全内垂直褥式缝合。术后根据Barrett标准门诊随访判断半月板的体部缝合临床愈合情况,采用重复测量方差分析比较不同时间视觉模拟评分(visual analogue scale,VAS)、膝关节主观功能评分(IKDC 2000评分)、膝关节功能评分(Lysholm评分)的差异来评估手术缝合疗效。术后12个月行膝关节MRI检查观察缝合部位恢复情况。结果本组36例患者均获随访,随访时间12-18个月,平均(15.0±2.3)个月。术后未出现感染、神经血管损伤、二次手术等并发症。根据Barrett标准评价,本组患者均获得半月板临床愈合。术后3个月、6个月、12个月的VAS评分为(1.10±0.12)分、(1.00±0.21)分、(0.90±0.32)分低于术前的(5.20±1.80)分,IKDC2000评分为(82.34±3.15)分、(85.34±5.17)分、(87.34±4.18)分高于术前的(40.51±5.54)分,Lysholm评分为(87.38±6.18)分、(88.52±4.19)分、(90.34±4.22)分高于术前的(42.11±6.82)分,差异具有统计学意义(P<0.05)。术后12个月复查MRI结果,34例(94.44%)甲级愈合,1例(2.78%)乙级愈合,1例(2.78%)未愈合。结论关节镜下采用AR缝合枪行全内垂直褥式缝合膝关节外侧半月板体部撕裂(层裂或纵裂),能有效缓解疼痛、提高患肢功能活动、促进半月板愈合,同时具有操作简单、并发症少等优势,经中短期临床随访其临床疗效显著,远期疗效需进一步随访追踪。  相似文献   
993.
Limitations of plain radiographs may contribute to poor sensitivity in the detection of knee osteoarthritis and poor correlation with pain and physical function. Three-dimensional (3D) joint space width (JSW), measured from weight-bearing computed tomography (CT) images, may yield a more accurate correlation with patients’ symptoms. We assessed the cross-sectional association between 3D JSW and self-reported pain and physical function. Five hundred twenty eight knees (57% women) were analyzed from Multicenter Osteoarthritis Study participants. An upright weight-bearing CT scanner was used to acquire bilateral, weight-bearing, fixed-flexion images of the knees. A 3D dataset was reconstructed from cone beam projections and JSW was calculated across the joint surface. The percentages of the apposed medial tibiofemoral joint surface with JSW less than 2.0 and 2.5 mm, respectively, were calculated. Pain and physical function were measured using Western Ontario and McMaster Universities Osteoarthritis Index. Participants who reported greater pain severity tended to have a greater joint area with JSW less than 2.0 mm (P = .07 for the highest vs the lowest tertile). Participants who reported greater functional limitations had a greater joint area with JSW less than 2.0 mm (P = .02 for the highest vs the lowest tertile). There appears to be an association between the medial tibiofemoral area with JSW less than 2.0 mm and pain and physical function.  相似文献   
994.
The majority of periprosthetic joint infections occur shortly after primary joint replacement (<3 months) and require the removal of all implant components for the treatment period (~4 months). A clinically relevant animal model of periprosthetic infection should, therefore, establish an infection with implant components in place. Here, we describe a joint replacement model in the rat with ultrahigh molecular weight polyethylene (UHMWPE) and titanium components inoculated at the time of surgery by methicillin-sensitive Staphylococcus aureus (S. aureus), which is one of the main causative microorganisms of periprosthetic joint infections. We monitored the animals for 4 weeks by measuring gait, weight-bearing symmetry, von Frey testing, and micro-CT as our primary endpoint analyses. We also assessed the infection ex vivo using colony counts on the implant surfaces and histology of the surrounding tissues. The results confirmed the presence of a local infection for 4 weeks with osteolysis, loosening of the implants, and clinical infection indicators such as redness, swelling, and increased temperature. The utility of specific gait analysis parameters, especially temporal symmetry, hindlimb duty factor imbalance, and phase dispersion was identified in this model for assessing the longitudinal progression of the infection, and these metrics correlated with weight-bearing asymmetry. We propose to use this model to study the efficacy of using different local delivery regimens of antimicrobials on addressing periprosthetic joint infections. Statement of clinical significance: We have established a preclinical joint surgery model, in which postoperative recovery can be monitored over a multi-week course by assessing gait, weight-bearing, and allodynia. This model can be used to study the efficacy of different combinations of implant materials and medication regimens. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:1101-1112, 2020  相似文献   
995.
Reducing airborne bioburden in total joint arthroplasty (TJA) is of critical importance. The efficacy of crystalline ultraviolet-C (C-UVC) filtration in reducing bioburden in a dynamic operating room (OR) environment has not been evaluated. We assessed whether C-UVC filtration reduced (i) total particle counts (TPC); (ii) viable particle counts (VPC); and (iii) colony-forming units (CFUs). Fifty primary TJA cases were performed in a positive-pressure OR; 25 cases with the C-UVC unit and 25 cases without. The air was sampled by a particle counter and an impact air sampler to measure particle counts and CFUs, respectively. To compare TPC, VPC, and CFU/m3 between groups, independent t tests and multivariate regression, adjusted for number of OR staff and door openings, were performed. The C-UVC group had significantly lower TPC (2.6 × 106 vs. 4.7 × 106 particles, p = 0.001) and VPC (18,605 vs. 27,516 particles, p = 0.001). There were fewer CFUs in the C-UVC group (10.9 CFU/m3 vs. 13.7 CFU/m3, p = 0.163). Multivariate analysis identified C-UVC filtration as a significant predictor of decreased TPC (β = −0.44, p = 0.002) and VPC (β = −0.47, p = 0.001) after accounting for door openings and number of OR staff. The reduction in CFUs was not significant on multivariate analysis. In this prospective pilot study, a C-UVC air disinfection and recirculation unit led to a significant reduction in both TPC and VPC and a non-significant reduction in CFU. Statement of clinical significance: Further studies are needed to investigate the effects of C-UVC filtration units on surgical-site infection rates. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:431-437, 2020  相似文献   
996.
BackgroundSecond-stage positive cultures in 2-stage revision arthroplasty are a matter of concern, as their influence in outcomes is not clearly defined. We sought to study reimplantation microbiology when using vancomycin-gentamicin prefabricated cement spacers in hip and knee periprosthetic joint infection. The associations of second-stage positive cultures with treatment failures and patient-associated factors were analyzed.MethodsWe conducted a retrospective cohort study, examining patients managed with 2-stage revision arthroplasty due to knee or hip chronic periprosthetic joint infection between 2010 and 2017. Prefabricated vancomycin-gentamicin cement spacers were used during the spacer stage. Intraoperative microbiological culture results after the first and second stages were evaluated. The primary end point was infection eradication or relapse.ResultsA total of 108 cases were included (61 hips and 47 knees). And 22.2% of patients had ≥1 second-stage positive culture, while 9.3% had ≥2 positive samples. Overall success, at an average follow-up of 46.4 months, was 77.8%. Treatment failure was higher among cases with positive cultures (15.5% vs 45.8%, P < .01) regardless of the number of positive samples. Diabetes was identified as a risk factor for second-stage positive cultures (P = .03); use of cement loaded with extra antibiotics for spacer fixation showed a protective effect (P < .01).ConclusionSecond-stage positive cultures were related to a higher failure rate when using vancomycin-gentamicin cement spacers. Diabetes increased the likelihood of second-stage positive cultures. The use of extra-antibiotic-loaded cement for spacer fixation during the first stage showed a protective effect.  相似文献   
997.
《The Journal of arthroplasty》2020,35(2):303-308.e1
BackgroundLength of stay (LOS) following total joint arthroplasty (TJA) continues to decrease. The effects of this trend on readmission risk and total cost are unclear. We hypothesize that optimal LOS following TJA minimizes index hospitalization, early readmission risk, and total cost.MethodsRetrospective data from the South Carolina Department of Revenue and Fiscal Affairs was reviewed for patients who underwent primary TJA in South Carolina from 2000 to 2015 (n = 172,760). Data for readmissions within 90 days were included. Severity of illness was estimated by Elixhauser score (EH). Index LOS is defined as the surgery and the subsequent hospital stay.ResultsPatients with more significant medical comorbidities (EH ≥ 4) had significantly longer LOS than healthier patients (4.0 vs 3.4 days, P < .001). Independent of EH, readmitted patients had a significantly longer index LOS than those never readmitted (4.3 vs 3.6 days, P < .001). For healthier patients (EH ≤ 3), each additional inpatient day increased readmission risk, while among sicker patients, staying 2 days vs 1 day was protective against readmission risk. Since 2000, the total index cost of TJA has doubled and average cost per inpatient day has tripled, but readmission rates remain essentially unchanged (7.4% to 7.0%).ConclusionIncreased LOS was associated with increased readmission risk. Patients with greater medical comorbidities stay longer to protect against readmission. Optimal LOS after TJA is highly influenced by the patient’s overall health. Despite a 300% increase in TJA daily cost, readmission rate has changed minimally over the last 15 years.  相似文献   
998.
《The Journal of arthroplasty》2020,35(7):1792-1799.e4
BackgroundPatient satisfaction after total hip (THA) and total knee arthroplasty (TKA) is a core outcome selected by the Outcomes Measurement in Rheumatology. Up to 20% of THA/TKA patients are dissatisfied. Improving patient satisfaction is hindered by the lack of a validated measurement tool that can accurately measure change.MethodsThe psychometric properties of a proposed satisfaction instrument, consisting of 4 questions rated on a Likert scale, scored 1-100, were tested for validity, reliability, and sensitivity to change using data collected between 2007 and 2011 in an arthroplasty registry.ResultsWe demonstrated construct validity by confirming our hypothesis; satisfaction correlated with similar constructs. Satisfaction correlated moderately with pain relief (TKA ρ = 0.61, THA ρ = 0.47) and function (TKA ρ = 0.65, THA ρ = 0.51) at 2 years; there was no correlation with baseline/preoperative pain/function values, as expected. Overall Cronbach’s alpha >0.88 confirmed internal consistency. Test-retest reliability with weighted kappa ranged 0.60-0.75 for TKA and 0.36-0.56 for THA. Hip disability and Osteoarthritis Outcome Score/Knee injury and Osteoarthritis Outcome Scores quality of life improvement (>30 points) corresponds to a mean satisfaction score of 93.2 (standard deviation, 11.5) after THA and 90.4 (standard deviation, 13.8) after TKA, and increasing relief of pain and functional improvement increased the strength of their association with satisfaction. The satisfaction measure has no copyright and is available free of cost and represents minimal responder burden.ConclusionPatient satisfaction with THA/TKA can be measured with a validated 4-item questionnaire. This satisfaction measure can be included in a total joint arthroplasty core measurement set for total joint arthroplasty trials.  相似文献   
999.
《The Journal of arthroplasty》2020,35(9):2363-2366
BackgroundAdvances in technique and perioperative blood management have improved transfusion rates following unilateral primary total joint arthroplasty and led some centers to change their preoperative blood ordering protocols. The purpose of this study is to determine whether deleting type and screens (T&S) from preoperative order sets was safe for patients undergoing primary total knee (TKA) and total hip arthroplasty (THA) and to identify patients who required allogenic blood transfusion.MethodsProspectively collected data were reviewed to identify any patient with a hemoglobin (Hgb) drawn within 30 days of surgery who received a transfusion following a unilateral primary TKA or THA.ResultsA total of 1255 patients met inclusion criteria. Of the total, 682 (54%) were TKAs and 573 (46%) were THAs. The mean preoperative Hgb was 11.5 g/dL with an average delta Hgb of 3.6 g/dL on postoperative day 1. No patient required an intraoperative transfusion. Fourteen patients (mean age and body mass index, 67.9 and 29.0) required a transfusion (1.1%) for postoperative blood loss anemia. Of those transfused, 13 (93%) of the patients underwent THA with the mean estimated blood loss of 378.6 mL. The total cost for a patient obtaining a T&S is $191.27.ConclusionIn our series, the risk of blood transfusion was rare (1.1%) and occurred only secondary to postoperative blood loss anemia. There were no cases of intraoperative complication requiring urgent or emergent blood transfusion. Removing T&S from standard order sets for patients undergoing primary TKA or THA appears to be a safe and cost-effective practice.  相似文献   
1000.
《The Journal of arthroplasty》2020,35(10):2938-2943
BackgroundUtilization of revision total knee arthroplasty (TKA) has been increasing, and reasons for failure are less understood than those of primary TKA. The purpose of this study is to identify the rates and mechanisms of failure of revision TKA, and compare those between a historic (1986-2005) and modern (2006-2015) cohort.MethodsAll revision TKAs performed at a single institution between 1986 and 2015 were reviewed, with minimum 2-year follow-up. Failure was defined as a second revision surgery in which any component was exchanged. Diagnosis at the time of index and any re-revision procedure was determined.ResultsIn total, 1632 revision TKAs in 1560 patients were reviewed. The average age was 65.1 and the average follow-up was 61.4 months. Overall failure rate was 22.8%, with no significant differences between the historic and modern cohort (25.1% vs 22.0%, P = .19). The leading cause for failure was infection in 38.5% of failures. The next most common causes for failure were aseptic loosening (20.9%) and instability (14.2%). Failure rate among revision TKAs for infection was 33%, with 67.2% failing due to repeat infection. Multivariate analysis found that septic index revision (odds ratio [OR] 1.91, 95% confidence interval [CI] 1.47-2.48), male gender (OR 1.41, 95% CI 1.11-1.78), and age less than 65 (OR 1.56, 95% CI 1.23-1.97) were independent risk factors for failure.ConclusionThere remains a high rate of failure in revision TKA, with infection being the most common reason for failure. Rates and primary reasons for failure have not changed significantly in the past decade.  相似文献   
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