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81.
Monosomy 7 mosaicism in metastatic choroidal melanoma   总被引:1,自引:1,他引:0  
Uveal melanoma is the most common primary intraocular malignancy in adults. Several cytogenetic studies on uveal melanoma cells have revealed that the majority of these cells harbor alterations in chromosomes 3, 6, and 8. This report describes the results of cytogenetic analysis performed on a fresh choroidal melanoma tissue sample from a patient with cerebellar metastasis. Monosomy 7 mosaicism was observed. To our knowledge, monosomy 7 has not been reported in patients with uveal melanoma. We suggest that observation of monosomy 7 may be related to an aggressive clinical behavior and unusual cerebellar metastasis in uveal melanoma. Further data are necessary to define the exact role of monosomy 7 in the pathogenesis and evolution of uveal melanoma.  相似文献   
82.
Despite transient, myelin-directed adaptive immune responses in regions of fiber tract degeneration, none of the current models of fiber tract injuries evokes disseminated demyelination, implying effective mechanisms maintaining or re-establishing immune tolerance. In fact, we have recently detected CD95L upregulation accompanied by apoptosis of leukocytes in zones of axonal degeneration induced by entorhinal cortex lesion (ECL), a model of layer-specific axonal degeneration. Moreover, infiltrating monocytes readily transformed into ramified microglia exhibiting a phenotype of immature (CD86+/CD80−) antigen-presenting cells. We now report the appearance of the axonal antigen neurofilament-light along with increased T cell apoptosis and enhanced expression of the pro-apoptotic gene Bad in cervical lymph nodes after ECL. In order to test the functional significance of such local and systemic depletory/regulatory mechanisms on subsequent immunity to central nervous system antigens, experimental autoimmune encephalomyelitis was induced by proteolipid protein immunization 30 days after ECL. In three independent experiments, we found significantly diminished disease scores and infiltrates in lesioned compared to sham-operated SJL mice. This is consistent with a previous meta-statistical analysis (Goodin et al. in Neurology 52:1737–1745, 1999) rejecting the O-hypothesis that brain trauma causes or exacerbates multiple sclerosis. Conversely, brain injuries may involve long-term tolerogenic effects towards brain antigens. Leman Mutlu, Christine Brandt, Jon D. Laman, and Ingo Bechmann have contributed equally.  相似文献   
83.
Biopsy is the gold standard of diagnostic procedures. The American Academy of Oral and Maxillofacial Pathology has stated its position concerning biopsy use in dental practice, believing that using the procedure more frequently will enhance diagnosis and contribute substantially to the quest for more evidence-based practice. Biopsy is a technique within the scope of practice of general dentists. It is vital to understand that biopsy is a tool for the diagnosis of myriad benign and malignant oral conditions. More frequent use of biopsy in dental practice will likely reduce the number of successful lawsuits brought for delay or failure to diagnose. This article offers 10 guidelines to dentists to help assure the success of the procedure.  相似文献   
84.
85.
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   
86.
Mitral inflow velocities are widely used for the evaluation of left ventricular (LV) diastolic function. However, they are closely affected by other factors such as preload. The purpose of this study was to evaluate the usefulness of tissue Doppler velocities obtained from the mitral annulus for the evaluation of ventricular relaxation in patients under different loading conditions. We also evaluated the effect of preload at different sides on the mitral annulus. The study population consisted of 62 consecutive patients (38 male, 24 female with a mean age of 42 ± 13 years) who have undergone hemodialysis. Both mitral inflow velocities (E wave, A wave, E wave deceleration time and isovolumetric relaxation time) and mitral annulus tissue Doppler velocities (E, A) from the septal, lateral, anterior, posterolateral and inferior sides of the mitral annulus were measured immediately before and after hemodialysis. Mitral inflow E and A wave velocities and E/A ratio decreased significantly (p < 0.001, p = 0.007, p < 0.001, respectively) after hemodialysis. Mitral annulus E wave velocities and E/A ratios obtained from five different sides of the annulus also changed significantly (p < 0.001 for all); however, there was no change in the A wave velocity (p > 0.05 for all) after hemodialysis. The decrease in E wave and E/A ratio in mitral inflow measurements and E velocities and E/A ratios in tissue Doppler measurements were correlated with the amount of fluid extracted (for mitral inflow E wave, r = 0.392, p = 0.002 and E/A ratio, r = 0.280 and p = 0.027; for lateral side E, r = 0.329, p = 0.009 and E/A ratio, r = 0.286, p = 0.04; for septal side E, r = 0.376, p = 0.003 and E/A ratio, r = 0.297, p = 0.019; for anterior side E, r = 0.342, p = 0.007 and E/A ratio, r = 0.268, p = 0.035; for posterolateral side E, r = 0.423, p = 0.001 and E/A ratio, r = 0.343, p = 0.007; and for inferior side E, r = 0.326, p = 0.01 and E/A ratio, r = 0.278, p = 0.029). We conclude that mitral annular velocities obtained by tissue Doppler are preload dependent parameters for the evaluation of LV diastolic function.  相似文献   
87.
The aim of the study is to evaluate the efficacy and safety of retrograde intrarenal surgery (RIRS) to treat renal stones in preschool age (<7 years) children. From September 2005 to May 2013, a total of 65 children (31 boys and 34 girls) with 72 renal stones were treated using RIRS. Patients were considered stone-free when the absence of residual fragments was observed on imaging studies. In the presence of residual calculi >4 mm, a second-stage RIRS was performed. The pre-operative, operative and post-operative data of the patients were retrospectively analyzed. A total of 65 patients with a mean age of 4.31 ± 1.99 years (6 months–7 years) were included in the present study. The mean stone size was 14.66 ± 6.12 mm (7–30 mm). The mean operative time was 46.47 ± 18.27 min. In 5 (7.69 %) patients, the initial procedure failed to reach the renal collecting system and ended with the insertion of a pigtail stent. The stone-free rates were 83.07 and 92.3 % after the first and second procedures, respectively. Complications were observed in 18 (27.7 %) patients and classified according to the Clavien system. Post-operative hematuria (Clavien I) occurred in 6 (9.2 %) patients, post-operative urinary tract infection with fever (Clavien II) was observed in 10 (15.4 %) patients, and ureteral wall injury (Clavien III) was noted in 2 (3 %) patients. RIRS is an effective and safe procedure that can be used to manage renal stones in preschool age children.  相似文献   
88.

Aim

To investigate the effects of oral carbohydrate solution consumed until 2 h before the surgery in the patients that would undergo open radical retropubic prostatectomy on postoperative metabolic stress, patient anxiety, and comfort.

Method

A total of 50 adult patients, who were in ASA I–II group and would undergo open radical retropubic prostatectomy, were included in the study. While Group 1 = CH (n = 25) received oral glucose solution, Group 2 = FAM (n = 25) was famished starting from 24:00 h. Blood glucose, insulin, and procalcitonin levels of the patients were recorded, and the patients completed state-trait anxiety inventory (STAI) test, which reflects the anxiety level of the patients, both before surgery and on the postoperative 24th hour. In order to evaluate patient comfort, senses of hunger, thirst, nausea, and cold were assessed in the morning prior to the surgery.

Results

No difference was observed between the two groups in terms of demographic data and insulin resistance levels (p > 0.05). Comparing with the preoperative levels, insulin resistance showed statistically significant elevation in both groups (p < 0.05). Procalcitonin levels were similarly increased in both groups in the postoperative period (p < 0.05). Preoperative and postoperative STAI state scores were similar in both groups (p > 0.05). With regard to preoperative patient comfort, sense of hunger was present in lesser number of subjects and at lower level in Group 1 (p < 0.05).

Conclusion

Preoperative consumption of high carbohydrate drink (Pre-op®) decreases insulin resistance and enhances patient comfort leading to lesser sense of hunger and thirst in the preoperative period in open radical retropubic prostatectomies.  相似文献   
89.
Background and aim. It has been demonstrated that right ventricular systolic dysfunction develops soon after surgical aortic valve replacement (s-AVR). While the impact of s-AVR or TAVI on the function of the left ventricle has been studied with various imaging modalities, little is known about the impact on right ventricular function (RVF). In the current study, we evaluated the impact of TAVI on RVF using conventional echocardiography parameters. Methods and results. Echocardiography was performed prior to 24 h, 1 month and 6 months after TAVI. RVF was assessed using (1) tricuspid annular plane systolic excursion (TAPSE); (2) RV Tissue Doppler Imaging (S’); (3) right ventricular systolic pressure (RVSP); (4) Fractional area change (FAC); and (5) RV ejection fraction (RVEF). TAVI was performed through the subclavian artery in two patients and femoral artery in 48 patients with an Edwards Sapien XT valve. TAVI was performed on 50 patients between the dates of December 2012 and June 2013. After TAVI, a statistically significant improvement was observed for all parameters related to RVF (RVSP, RVEF, TAPSE, FAC, RVTDI S’). During the 1st and 6th months this statistically significant improvement continued in TAPSE and FAC, and there was no deterioration in RVSP, RVEF, and RVTDI S during the 1st month but a statistically significant improvement continued in the 6th month. Conclusion. RVF assessed by conventional echocardiography did not deteriorate after TAVI in early and midterm follow-up. Further, TAVI provides improvement of RVF and can safely and efficiently be performed in patients with impaired RVF.  相似文献   
90.
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