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31.
Multidetector computed tomography (MDCT) and Doppler ultrasound findings of a renal cell carcinoma invading the right ovarian vein are presented. An MDCT study performed for evaluation of macroscopic hematuria showed a heterogeneously enhancing malignant thrombus in the right ovarian vein that was in continuity with inferior vena cava and right renal vein thrombi of identical characteristics. Further investigation with Doppler ultrasound confirmed these findings and showed arterial blood flow of low resistance within the ovarian vein and inferior vena cava thrombi. To the authors' knowledge, this is the first report of MDCT and Doppler ultrasound findings of a renal cell carcinoma invading the right ovarian vein.  相似文献   
32.
Multirater agreement of arthroscopic grading of knee articular cartilage   总被引:2,自引:0,他引:2  
BACKGROUND: Acute and chronic cartilage injury of the knee has an important impact on prognosis. The validity of the classification of such injuries is critical for prospective multicenter studies. The agreement among multiple surgeons at different institutions for articular cartilage lesions has not been established. HYPOTHESIS: Arthroscopic classification of articular cartilage lesions is reliable and reproducible and can be used for multicenter studies involving multiple surgeons. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 1. METHODS: A total of 6 surgeons from 5 centers reviewed 31 videos of articular cartilage lesions. With grade 2 and grade 3 combined for the analysis, observed agreement ranged from 81% to 94%, and kappa ranged from 0.34 to 0.87. An additional 22 videos comprising grade 2 and grade 3 lesions were analyzed, and the observed agreement was 80%, with an overall kappa of 0.47. CONCLUSION: Arthroscopic grading of articular cartilage lesions is reproducible among surgeons at different centers. CLINICAL RELEVANCE: Articular cartilage lesions can be reliably classified among surgeons at different sites. Such reliability is important for multicenter clinical research studies involving arthroscopic knee surgery.  相似文献   
33.
BACKGROUND: The purpose of this study was to assess the functional outcome of opening wedge high tibial osteotomy (HTO) in a young, active group of patients with instability rather than osteoarthritis. METHODS: The results of 17 opening wedge HTOs in 16 patients with a symptomatic hyperextension-varus thrust were evaluated. Functional results were evaluated according to the activity scoring system of Tegner and Lysholm and using a 5-point visual analogue scale to assess change in knee stability and satisfaction. Radiographs were analyzed to determine changes in femorotibial and mechanical axis alignment, tibial slope, and patellar height. RESULTS: Patients were followed for a mean of 56 months. All patients had an increase in their activity score postoperatively. Nine patients rated their symptoms as significantly better and seven as somewhat better. All but one were satisfied with the surgery. Femorotibial axis alignment was changed to a mean of 6 degrees valgus, mechanical axis alignment was corrected to a mean of 46% toward the lateral compartment, posterior tibial slope was increased a mean of 8 degrees, and the ratio of patellar height was decreased a mean of 0.17. CONCLUSION: Opening wedge HTO can produce good functional and radiographic results in selected patients with a symptomatic thrust.  相似文献   
34.
BACKGROUND: Establishing the validity of classification schemes is a crucial preparatory step that should precede multicenter studies. There are no studies investigating the reproducibility of arthroscopic classification of meniscal pathology among multiple surgeons at different institutions. HYPOTHESIS: Arthroscopic classification of meniscal pathology is reliable and reproducible and suitable for multicenter studies that involve multiple surgeons. STUDY DESIGN: Multirater agreement study. METHODS: Seven surgeons reviewed a video of 18 meniscal tears and completed a meniscal classification questionnaire. Multirater agreement was calculated based on the proportion of agreement, the kappa coefficient, and the intraclass correlation coefficient. RESULTS: There was a 46% agreement on the central/peripheral location of tears (kappa = 0.30), an 80% agreement on the depth of tears (kappa = 0.46), a 72% agreement on the presence of a degenerative component (kappa = 0.44), a 71% agreement on whether lateral tears were central to the popliteal hiatus (kappa = 0.42), a 73% agreement on the type of tear (kappa = 0.63), an 87% agreement on the location of the tear (kappa = 0.61), and an 84% agreement on the treatment of tears (kappa = 0.66). There was considerable agreement among surgeons on length, with an intraclass correlation coefficient of 0.78, 95% confidence interval of 0.57 to 0.92, and P < .001. CONCLUSIONS: Arthroscopic grading of meniscal pathology is reliable and reproducible. CLINICAL RELEVANCE: Surgeons can reliably classify meniscal pathology and agree on treatment, which is important for multicenter trials.  相似文献   
35.
BACKGROUND: Evaluation of the knee after an anterior cruciate ligament reconstruction with the use of the semitendinosus and gracilis (hamstring) autografts has primarily focused on flexion and extension strength. The semitendinosus and gracilis muscles contribute to internal tibial rotation, and it has been suggested that harvest of these tendons for the purpose of an anterior cruciate ligament reconstruction contributes to internal tibial rotation weakness. HYPOTHESIS: Internal tibial rotation strength may be affected by the semitendinosus and gracilis harvest after anterior cruciate ligament reconstruction. STUDY DESIGN: Prospective evaluation of internal and external tibial rotation strength. METHODS: Inclusion criteria for subjects (N = 30): unilateral anterior cruciate ligament reconstruction at least 2 years previously, a stable anterior cruciate ligament (<5-mm side-to-side difference) at time of testing confirmed by surgeon and KT-1000 arthrometer, no history of knee problems after initial knee reconstruction, a normal contralateral knee, and the ability to comply with the testing protocol. In an attempt to minimize unwanted subtalar joint motion, subjects were immobilized using an ankle brace and tested at angular velocities of 60 degrees /s, 120 degrees /s, and 180 degrees /s at a knee flexion angle of 90 degrees . RESULTS: The mean peak torque measurements for internal rotation strength of the operative limb (60 degrees /s, 17.4 +/- 4.5 ft-lb; 120 degrees /s, 13.9 +/- 3.3 ft-lb; 180 degrees /s, 11.6 +/- 3.0 ft-lb) were statistically different compared to the nonoperated limb (60 degrees /s, 20.5 +/- 4.7 ft-lb; 120 degrees /s, 15.9 +/- 3.8 ft-lb; 180 degrees /s, 13.4 +/- 3.8 ft-lb) at 60 degrees /s (P = .012), 120 degrees /s (P = .036), and 180 degrees /s (P = .045). The nonoperative limb demonstrated greater strength at all speeds. The mean torque measurements for external rotation were statistically similar when compared to the nonoperated limb at all angular velocities. CONCLUSIONS: We have shown through our study that patients who undergo surgical intervention to repair a torn anterior cruciate ligament with the use of autogenous hamstring tendons demonstrate with weaker internal tibial rotation postoperatively at 2 years when compared to the contralateral limb.  相似文献   
36.
Influenza and Streptococcus pneumoniae diseases can cause severe complications in HIV-1 infected individuals leading to increases in hospital admission and even death. Both vaccinations are recommended for such individuals, but some studies reported that such immunizations may stimulate an increase of HIV-1 viral load and decrease of CD4+ cells count. A review of published studies, including our studies carried out in HIV-1 infected former drugs addicts, indicates that influenza and pneumococcal vaccinations are well tolerated in individuals with HIV-1, and do not induce deterioration of the course of HIV-1 infection, even though the immune response to vaccination is lower than that one observed in immunocompetent individuals. Therefore the lack of significant changes of virological and immunological parameters indicates that such immunizations can be safely administrated to HIV-1 infected individuals.  相似文献   
37.
BACKGROUND AND PROCEDURE: Nm23 gene family has been associated with metastasis suppression and differentiation. We studied DR-nm23 during neuroblastoma cells differentiation. DR-nm23 expression increased after retinoic acid induction of differentiation in human cell lines SK-N-SH and LAN-5. RESULTS: In several cell lines, overexpression of DR-nm23 was associated with more differentiated phenotypes. SK-N-SH cells increased vimentin expression, increased deposition of collagen type IV, modulated integrin expression, and underwent growth arrest; the murine neuroblastoma cell line N1E-115 showed neurite outgrowth and a striking enhancement of beta1 integrin expression. Up-regulation of beta1 integrin was specifically responsible for the increase in the adhesion to collagen type I-coated plates. Finally, cells overexpressing DR-nm23 were unable to growth in soft agar. CONCLUSIONS: In conclusion, DR-nm23 expression is directly involved in differentiation of neuroblastoma cells, and its ability to affects the adhesion to extracellular substrates and to inhibit growth in soft agar suggests an involvement in the metastatic potential of neuroblastoma.  相似文献   
38.
AIM: Neurologically impaired (NI) children present with neuromuscular incoordination and severe gastroesophageal reflux (GER). In these cases, Bianchi has proposed total oesophagogastric dissociation (OGD) as a primary procedure and not only after failed fundoplication. METHODS: Anthropometric and laboratory data, incidence of respiratory symptoms, days of hospitalisation, time of feeding, stool frequency and quality of life were tested preoperatively and after OGD over a 12-month period in 13 severe NI patients. RESULTS: Results are shown in Table 1. We also recorded improvement in quality of life, based on communication by the person responsible for the care of the subject, and determined by psychological interviews. CONCLUSIONS: OGD is a successful and feasible procedure and can be included as a primary definitive surgical treatment in individualised nutritional rehabilitation planning for each severe NI child.  相似文献   
39.
Flow cytometric (FCM) DNA content measurements were performed on testicular monocellular suspensions obtained from mice exposed per os to 0, 1, 2, 4, 6, and 7 ml/kg body weight of benzene in order to investigate its cytotoxic action on germ cells. The effects of benzene were measured 7, 14, 21, 28, and 70 d after treatment. Benzene had no effect on testis weight, but FCM analysis showed the relative percentages of some cell subpopulations (tetraploid and haploid cells) to be different from the control pattern, indicating the occurrence of some cytotoxic damage to differentiating spermatogonia. These data demonstrate that spermatogenesis is sensitive to benzene single exposures as evidenced by an altered cell ratio of testicular cell types.  相似文献   
40.
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