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991.

Background

As the indications for total hip arthroplasty (THA) have expanded, this procedure is being increasingly performed in young patients. Oftentimes, this population has undergone one or more salvage procedures in an attempt to delay or forestall a THA. However, it is unclear whether patients with prior salvage procedure have higher risk of adverse events.

Methods

From 2004 to 2014, 215 THAs performed in patients less than 30 years at a single institution were identified. These patients were screened to identify 37 THAs in which one or more salvage procedures were performed prior to the THA (salvage group). The prior salvage procedures were open in 30 (pelvic osteotomy = 5, femoral osteotomy = 15, combined osteotomy = 2, core decompression = 7, bone graft = 1) and arthroscopic in 7. Medical and surgical complications within 90 days and overall survivorship at a minimum follow-up of 2 years were recorded. Nonparametric tests and Kaplan-Meier survival curves were used to compare the groups.

Results

Salvage group had a higher rate of wound complications (P = .037), superficial infections (P = .005), and reoperations (P = .015). The 5-year survivorships in the salvage and nonsalvage groups were 97.1% and 96.7%, respectively (P = .787).

Conclusion

Patients less than 30 years who undergo THA after a previous salvage procedure have a higher risk of wound complications, superficial infections, and reoperations, but similar survivorship, compared to those who did not have any prior salvage procedures. This information is helpful in counseling young patients while offering various surgical options for the management of various hip pathologies.  相似文献   
992.

Background

Recurrent hemarthrosis is a late complication in up to 1.6% of patients following total knee arthroplasty (TKA). In the absence of intrinsic coagulopathy, one etiology is bleeding of hypertrophic vascular synovium. The aim of this study is to evaluate the clinical outcome of patients referred to our center for angiographic embolization of geniculate arteries for recurrent hemarthrosis following TKA.

Methods

We retrospectively studied a cohort of patients who were referred for geniculate artery embolization following TKA between August 2011 and September 2016.

Results

A total of 24 embolization procedures were performed on 14 patients. Seven (50%) of these 14 patients underwent one embolization procedure. Due to symptom recurrence, 4 patients underwent a repeated procedure and 3 patients a third procedure. All embolization procedures were technically successful at the time of the procedure. Two patients reported an inguinal hematoma that healed without further treatment. At follow-up of mean 26.8 months, clinical success was achieved in 12 of the 14 patients (86%).

Conclusion

Embolization of the geniculate arteries in our study was a safe and effective treatment of recurrent spontaneous hemarthrosis following TKA. Although we have performed a substantial number of reinterventions, results of this study show that this procedure can be safely repeated without adverse events. Our results indicate that embolization could possibly be the treatment of choice when conservative measures fail and can be repeated in the event of recurrent or persistent symptoms.  相似文献   
993.

Background

Active robotic total hip arthroplasty (THA) has been used clinically for over 20 years, but long-term results have never been studied. The aims of this study are to determine whether active robotic THA improves clinical outcomes and results in fewer revisions over a long-term follow-up.

Methods

Patients from 2 US Food and Drug Administration clinical trials (1994-1998 and 2001-2006) who had undergone THA using either an active robotic system or a traditional manual technique were examined to determine if any differences existed in radiographic analysis and patient pain and function using the University of California, Los Angeles; visual analog scale; Health Status Questionnaire (HSQ) pain; HSQ role physical; HSQ physical functioning; Harris pain scores; and the total Western Ontario and McMaster Universities Osteoarthritis Index scores at a mean follow-up of 14 years.

Results

The ROBODOC group had statistically significant higher HSQ pain and Harris pain scores and lower Western Ontario and McMaster Universities Osteoarthritis Index scores. There was no statistically significant difference in probability of a revision for wear between the groups (χ2 = 1.80; P = .179), and no revisions for loosening in either group.

Conclusion

Prior studies have demonstrated improved implant fit and alignment with the use of this active robot system. This long-term study now shows no failures for stem loosening at a mean follow-up of 14 years and small but potentially important improvements in clinical outcomes in the robot group.  相似文献   
994.

Background

The aim of this study is to investigate differences in implant requirement, outcomes, and re-revision when total knee arthroplasty (TKA) was performed following unicompartmental knee arthroplasties (UKAs) with metal-backed (MB) compared to all-polyethylene (AP) tibial components.

Methods

Retrospective study of 60 UKAs converted to 60 TKAs at mean 7.3 years (0.1 to 17) after implantation in 55 patients (mean age, 64 [49-83]; 44% male): 44 MB and 16 AP. TKA implant requirement was investigated in addition to mode of failure, Oxford Knee Score, and TKA survival at mean 5.4 years (0.5 to 17).

Results

Progression of osteoarthritis was the commonest mode of failure in MB UKAs (P = .03) and unexplained pain in AP (P = .011) where revisions were performed earlier (4.8 ± 3.2 vs 8.2 ± 4.5, P = .012). In 56 of 60 (93%) cases, unconstrained TKA implants were used. The use of standard cruciate-retaining TKAs without augments or stems was less likely following MB UKA compared to AP (12 of 38 [32%] vs 10/14 [71%], P = .013). Specifically MB UKA implants were associated with more tibial stem use (P = .04) and more use of cruciate-substituting polyethylene (P = .05). There was no difference in the use of constrained implants. Multivariate analysis showed tibial resection depth to predict stem requirement. Seven were re-revised giving 7-year TKA survival: from MB UKA 70.3 (95% CI, 47.0 to 93.6) and from AP UKA 87.5 (95% CI, 64.6 to 100; P = .191).

Conclusion

MB UKA implants increase the chances of a complex revision requiring tibial stems and cruciate substitution but reduce the chances of early revision compared to AP UKA which often fail early with pain.  相似文献   
995.

Background

This study aimed to identify the factors affecting postoperative rotational limb alignment of the tibia relative to the femur. We hypothesized that not only component positions but also several intrinsic factors were associated with postoperative rotational limb alignment.

Methods

This study included 99 knees (90 women and 9 men) with a mean age of 77 ± 6 years. A three-dimensional (3D) assessment system was applied under weight-bearing conditions to biplanar long-leg radiographs using 3D-to-2D image registration technique. The evaluation parameters were (1) component position; (2) preoperative and postoperative coronal, sagittal, and rotational limb alignment; (3) preoperative bony deformity, including femoral torsion, condylar twist angle, and tibial torsion; and (4) preoperative and postoperative range of motion (ROM).

Results

In multiple linear regression analysis using a stepwise procedure, postoperative rotational limb alignment was associated with the following: (1) rotation of the component position (tibia: β = 0.371, P < .0001; femur: β = ?0.327, P < .0001), (2) preoperative rotational limb alignment (β = 0.253, P = .001), (3) postoperative flexion angle (β = 0.195, P = .007), and (4) tibial torsion (β = 0.193, P = .010).

Conclusion

In addition to component positions, the intrinsic factors, such as preoperative rotational limb alignment, ROM, and tibial torsion, affected postoperative rotational limb alignment. On a premise of correct component positions, the intrinsic factors that can be controlled by surgeons should be taken care. In particular, ROM is necessary to be improved within the possible range to acquire better postoperative rotational limb alignment.  相似文献   
996.

Background

Orthopedic surgeons utilize the 22-modifier when billing for complex procedures under the American Medical Association's Current Procedural Terminology (CPT) for reasons such as excessive blood loss, anatomic abnormality, and morbid obesity, cases that would ideally be reimbursed at a higher rate to compensate for additional physician work and time. We investigated how the 22-modifier affects physician reimbursement in knee and hip arthroplasty.

Methods

We queried hospital billing data from 2009 to 2016, identifying all cases performed at our urban tertiary care orthopedic center for knee arthroplasty (CPT codes 27438, 27447, 27487, and 27488) and hip arthroplasty (CPT codes 27130, 27132, 27134, 27236). We extracted patient insurance status and reimbursement data to compare the average reimbursement between cases with and without the 22-modifier.

Results

We analyzed data from 2605 procedures performed by 10 providers. There were 136 cases with 22-modifiers. For knee arthroplasty (n = 1323), the 22-modifier did not significantly increase reimbursement after adjusting for insurer, provider, and fiscal year (4.2% dollars higher on average, P = .159). For hip arthroplasty (n = 1282), cases with a 22-modifier had significantly higher reimbursement than those without the 22-modifier (6.2% dollars more, P = .049). For hip arthroplasty cases with a 22-modifier, those noting morbid obesity were reimbursed 29% higher than those cases with other etiology.

Conclusions

The effect of the 22-modifier on reimbursement amount is differential between knee and hip arthroplasty. Hip arthroplasty procedures coded as 22-modifier are reimbursed more than those without the 22-modifier. Providers should consider these potential returns when considering submitting a 22-modifier.  相似文献   
997.

Background

Postoperative knee flexion angle is one of the most important outcomes of total knee arthroplasty (TKA). Intraoperative ligament balancing may affect the postoperative range of motion of the knee. However, the relationship between intraoperative ligament balancing and postoperative flexion angle was still controversial. The purpose of this study was to determine whether intraoperative joint gap affects postoperative knee flexion angle or not.

Methods

Prospective multicenter study of 246 knees with varus osteoarthritis undergoing a posterior–stabilized, mobile-bearing TKA was performed. The joint gap before implantation and after implantation was measured. The joint gap after implantation was measured using a specially designed tensor device with the same shape of a total knee prosthesis at 0°, 30°, 60°, 90°, 120°, and 145° of flexion with the reduction of the patellofemoral joint. Stepwise multiple regression analysis was conducted to determine the predictors of the flexion angle of the knee after the operation.

Results

Predictors were identified in the following 3 categories: (1) preoperative flexion angle, (2) intraoperative flexion angle, and (3) joint gap looseness at 120° of flexion (joint gap after implantation at 120° of flexion ? joint gap after implantation at 0° of flexion) (R = 0.472, P < .01).

Conclusion

Flexion angle after TKA was not affected by the flexion joint gap looseness before implantation and the joint gap looseness after implantation from 30° to 90° of flexion. Surgeons should notice that joint gap looseness in mid-flexion range did not increase the postoperative knee flexion angle.  相似文献   
998.

Background

Laxity of soft tissues after total hip arthroplasty is considered to be a cause of accelerated wear of bearing surfaces and dislocation. The purpose of this study is to assess the contribution of the anterior and posterior capsular ligamentous complexes and the short external rotators, except the quadratus femoris, on the stability of the hip against axial traction.

Methods

The study subjects comprised 7 fresh cadavers with 12 normal hip joints. In 6 hips, soft tissues surrounding the hip joint were resected in the following order to simulate the anterior approach: anterior capsule, posterior capsule, piriformis, conjoined tendon, and external obturator. In the remaining 6 hips, soft tissues were resected in the following order to simulate the posterior approach: piriformis, conjoined tendon, external obturator, posterior capsule, and anterior capsule. Soft tissue tension was measured by applying traction amounting to 250 N with joints in the neutral position.

Results

The separation distance between the femoral head and acetabulum during axial leg traction significantly increased from 4.0 to 14.5 mm on average after circumferential resection of the capsule via the anterior approach. Subsequent resection of the short external rotators increased the separation distance up to 19.0 mm, but the differences did not reach statistical significance. Resection of the short external rotators via the posterior approach did not significantly increase the separation distance; it significantly increased from 6.0 to 11.4 mm after the resection of the anterior capsule and further to 20.5 mm after the resection of the posterior capsule.

Conclusion

The posterior capsule, in addition to the anterior capsule, significantly contributes to hip joint stability in distraction regardless of whether the short external rotators, except the quadratus femoris, were preserved or resected.  相似文献   
999.

Background

Despite the advantages of large, national datasets, one continuing concern is missing data values. Complete case analysis, where only cases with complete data are analyzed, is commonly used rather than more statistically rigorous approaches such as multiple imputation. This study characterizes the potential selection bias introduced using complete case analysis and compares the results of common regressions using both techniques following unicompartmental knee arthroplasty.

Methods

Patients undergoing unicompartmental knee arthroplasty were extracted from the 2005 to 2015 National Surgical Quality Improvement Program. As examples, the demographics of patients with and without missing preoperative albumin and hematocrit values were compared. Missing data were then treated with both complete case analysis and multiple imputation (an approach that reproduces the variation and associations that would have been present in a full dataset) and the conclusions of common regressions for adverse outcomes were compared.

Results

A total of 6117 patients were included, of which 56.7% were missing at least one value. Younger, female, and healthier patients were more likely to have missing preoperative albumin and hematocrit values. The use of complete case analysis removed 3467 patients from the study in comparison with multiple imputation which included all 6117 patients. The 2 methods of handling missing values led to differing associations of low preoperative laboratory values with commonly studied adverse outcomes.

Conclusion

The use of complete case analysis can introduce selection bias and may lead to different conclusions in comparison with the statistically rigorous multiple imputation approach. Joint surgeons should consider the methods of handling missing values when interpreting arthroplasty research.  相似文献   
1000.

Background

The demand for conversion of prior hip surgery to total hip arthroplasty (conversion THA) is likely to increase as a function of increasing US hip fracture burden in addition to its application in managing other conditions. Thus, outcome analysis is warranted to better inform value-based reimbursement schemes in the era of bundled payments.

Methods

Via Current Procedural Terminology codes, the National Surgical Quality Improvement Project data files were queried for all patients who underwent primary THA and conversion of previous hip surgery to THA from 2005 to 2014. To better understand the isolated effect of procedure type on adverse outcomes, primary and conversion cohorts were then propensity-score matched via logistic regression modeling. Comparisons of the study's primary outcomes were drawn between matched cohorts. Statistical significance was defined by a P-value less than or equal to .05.

Results

Relative to the primary THA group, the conversion THA group had statistically greater rates of Center Medicare and Medicaid Services (CMS) complications (7.5% vs 4.5%), non-home bound discharge (19.6% vs 14.7%), and longer length of hospital stay. Conversion THA was associated with increased likelihood of CMS complications (odds ratio 1.68, confidence interval 1.39-2.02) and non-home bound discharge (odds ratio 1.41, confidence interval 1.25-1.58). No statistically significant differences in mortality and readmission were detected.

Conclusion

The elevated risk for CMS-reported complications, increased length of hospital stay, and non-home bound discharge seen in our study of conversion THA indicates that it is dissimilar to elective primary THA and likely warrants consideration for modified treatment within the Comprehensive Care for Joint Replacement structure in a manner similar to THA for fracture.  相似文献   
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