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INTRODUCTION: Surgical findings of traumatic neurapraxia and neurotmesis in digital nerve injuries of hand have significantly different prognosis and surgeons managing such injuries must be able to provide the expected incidence of these injuries along with decision on surgical exploration. There is a paucity of data in the literature defining the incidence of traumatic neurapraxia and neurotemesis in lacerated hand injuries with clinical features of digital nerve injury. MATERIALS AND METHODS: We carried out a study in an urban practice to understand this problem on 81 consecutive patients with 82 digital nerve injuries over 1.5 years. Seventy-two percent of the injuries were caused mainly in the domestic accidents by glass and knife. All patients had clinical features of digital nerve injury. RESULTS: Operative findings revealed nerve damage in 76 patients (confidence interval at 95% = 91-97). Seventy-one had severed nerves and underwent repair (CI at 95% = 80-95). There were 7% patients with operative findings of normal looking nerves and 6% of bruised but intact nerves. All of these 13% patients who did not require surgical repair were grouped as traumatic neurapraxia and showed complete clinical recovery. CONCLUSION: Traumatic neurapraxia in digital nerve injuries of the hand are not uncommon, as previously thought, following lacerated injuries to hand and have favourable prognosis. This information is important for clinicians in getting more informed consent and patient education. The classification of digital nerve injuries into traumatic neurapraxia and neurotemesis appears logical for its practical application in routine clinical practice.  相似文献   
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Background

The introduction of technique of radiofrequency (RF) catheter ablation in 1990, has revolutionized management of different types of paroxysmal supraventricular tachycardia (PSVT). In spite of higher success rate, there were reported recurrences among different types of SVT. The aim of this study was to report the efficacy of RF ablation, its complications, recurrence rate and its predictors.

Methods

The material of this study (our 3rd registry) included patients who underwent electrophysiological study (EPS) and radiofrequency ablation of their supraventricular tachycardia in the past 5 years, starting from January 2002 to January 2007 at The Critical Care Medicine Department, Cairo University.

Results

Out of 400 pts studied, 381 (95%) had been subjected to radiofrequency ablation (RF) ablation while the remaining 19 pts (4.7%) refused ablation for fear of possible complications. Out of the 381 pts, 366 (96%) had their target tachycardia successfully terminated, from them 26 pts (7%) experienced recurrence after having successful RF ablation. Nine pts (34.6%) of total recurrence was reported in pts with AVNRT, 7 pts (26.9%) of total recurrence was reported in pts with AVRT utilizing septal accessory pathway (Rt AS and /or Rt PS AP), 4 pts (15.4%) was reported in pts with double AP, 2 pts (7.7%) of total recurrence was reported in pts with AFl, one pt (3.8%) of total recurrence was reported in cases of AT. Redo ablation have been carried out successfully in 25 pts (96.2%), and one pt (3.8%) refused ablation for fear of possible complications.

Conclusions

Although electrophysiological study and RF ablation eliminated different types of SVT. However, there may be increased incidence of recurrence among pts with AVNRT and AVRT utilizing concealed septal AP and multiple APs secondary to the complexity of AVN physiology, the critical location of septal AP, the clinical expertise, and poor electrophysiological criteria for good procedural success.  相似文献   
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Epstein-Barr virus (EBV) persistently infects more than 90% of the human population and is etiologically linked to several B cell malignancies, including Burkitt lymphoma (BL), Hodgkin lymphoma (HL), and diffuse large B cell lymphoma (DLBCL). Despite its growth transforming properties, most immune-competent individuals control EBV infection throughout their lives. EBV encodes various oncogenes, and of the 6 latency-associated EBV-encoded nuclear antigens, only EBNA3B is completely dispensable for B cell transformation in vitro. Here, we report that infection with EBV lacking EBNA3B leads to aggressive, immune-evading monomorphic DLBCL-like tumors in NOD/SCID/γc-/- mice with reconstituted human immune system components. Infection with EBNA3B-knockout EBV (EBNA3BKO) induced expansion of EBV-specific T cells that failed to infiltrate the tumors. EBNA3BKO-infected B cells expanded more rapidly and secreted less T cell-chemoattractant CXCL10, reducing T cell recruitment in vitro and T cell-mediated killing in vivo. B cell lines from 2 EBV-positive human lymphomas encoding truncated EBNA3B exhibited gene expression profiles and phenotypic characteristics similar to those of tumor-derived lines from the humanized mice, including reduced CXCL10 secretion. Screening EBV-positive DLBCL, HL, and BL human samples identified additional EBNA3B mutations. Thus, EBNA3B is a virus-encoded tumor suppressor whose inactivation promotes immune evasion and virus-driven lymphomagenesis.  相似文献   
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BackgroundWe aimed to assess the decrease in contrast media volume (CMV) with ultra-low contrast delivery technique (ULCD) developed at our institution versus the usual automated contrast injector system (ACIS) contrast delivery in coronary procedures.MethodsWe analyzed the amount of contrast given in the consecutive 204 patients of the operators who use ULCD technique versus consecutive 200 patients of the other operators who use ACIS without ULCD technique for coronary angiograms and/or percutaneous coronary interventions (PCIs) from May 2017 to July 2018 at our center. We calculated the mean CMV between these groups.ResultsWe observed a significant reduction in mean CMV with ULCD technique versus standard ACIS, respectively: angiogram 24.8 ± 15.8 mL (n = 194) vs 42.3 ± 25.1 mL (n = 200) (p < 0.0001); PCI 23.5 ± 19.7 mL (n = 52) vs 48.2 ± 30.8 mL (n = 16) (p < 0.0070); angiogram with ad hoc PCI 53.4 ± 32.1 mL (n = 23) vs 89.7 ± 35.6 mL (n = 16) (p < 0.0024); and overall angiogram and PCI 27.4 ± 20.5 mL (n = 204) vs 44.9 ± 28.0 mL (n = 181) (p < 0.0001).ConclusionOur study showed a highly significant reduction in CMV using ULCD technique compared to standard ACIS contrast delivery in coronary invasive procedures. Even in the standard ACIS arm, CMV was significantly lower than values reported in literature, possibly due to operators' bias toward contrast preservation.  相似文献   
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Malignant melanoma is notorious for its remarkable morphological variation and aberrant histopathological patterns. However, melanoma with prominent cartilaginous transdifferentiation simulating chondrosarcoma is extremely rare. A 75‐year‐old male developed a swelling in his left inguinal region and was diagnosed with a metastatic melanoma, which was found to harbor a BRAF V600E mutation. Later on, the left inguinal lymph node was excised and immunohistochemistry done on the specimen revealed an undifferentiated component negative for S‐100 protein, HMB‐45 and Melan‐A and a cartilaginous component positive for S‐100 protein and diffusely positive for BRAF V600E mutation. To our knowledge, there are around 14 cases reported in the literature of malignant melanoma with pure cartilaginous transdifferentiation. In all cases, immunohistochemistry of the cartilaginous component was positive for S‐100, which is not an indicator of melanoma because cartilage expresses S‐100. BRAF mutational studies support that the tumor arose from a common melanoma cell that harbored the mutation and subsequently transdifferentiated. This case illustrates the importance of an accurate and thorough clinical assessment when it comes to the diagnosis of melanomas as they are notable for their impressive degree of morphologic variability. Moreover, this report helps shed light on the use of immunohistochemical analysis to reach a definitive diagnosis.  相似文献   
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Background

Periprosthetic fracture following total hip arthroplasty is a significant problem faced by hip surgeons, and its management in elderly patients remains a considerable challenge.

Methods

We retrospectively reviewed 28 Vancouver B2 and B3 periprosthetic femoral fractures (PFF) treated with revision of the femoral stems by distally locked, hydroxyapatite-coated uncemented stems (Cannulok). Patients were aged 75 years or older at the time of surgery.

Results

The mean follow-up was 44.6 months (range, 24-102). The mean postoperative Oxford hip score was 30.1 (range, 10-46). The rate of fracture union was 95.8%, and the survivorship of the stem was 100% at the end of follow-up.

Conclusion

The management of PFF in elderly is associated with increased postoperative morbidity and mortality. The use of a distally locked, hydroxyapatite-coated femoral stem is a valid option for the treatment of PFF to achieve fracture union with a low rate of revision.  相似文献   
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