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1.
A unique case of a malignant oncocytoma of the maxillary sinus is reviewed in detail. The ultrastructural findings are presented. The histologic and ultrastructural criteria that characterize onco-cytes and the clinicopathologic features of benign and malignant oncocytomas are discussed. This case represents the eleventh reported case that would truly qualify as a malignant oncocytoma of the paranasal sinuses.  相似文献   
2.
HLA polymorphisms in Nigerians   总被引:2,自引:0,他引:2  
The HLA class I and class II phenotypes of a panel of 114 unrelated Nigerians have been determined. The panel was tested for all the known class I antigens and comparisons of the HLA-A and -B frequencies with those of other African Negroid populations revealed some differences. Only limited comparisons could be made for the HLA-DR and -D frequencies as these are not available for any well-defined African Negroid population. The data concerning the class II antigens of this panel are the most interesting. Half of the DRw11-positive panel members are DQw3 negative and DQw1 positive. In addition, there is dissociation of some HLA-D and -DR specificities, a number of panel members are positive for an HLA-D specificity and are negative for the corresponding HLA-DR specificity. Our results show the value of population studies in the investigation of the relationship between the different HLA class II antigens.  相似文献   
3.
The impact of hydrosalpinx (HSPX) on in-vitro fertilization (IVF) outcome has recently been the subject of intense debate. Most, but not all, studies have reported decreased implantation and pregnancy rates and increased early pregnancy loss in HSPX patients. This has led to prophylactic salpingectomies prior to IVF in HSPX patients despite the lack of any prospective studies to suggest that any improvement will occur. Women with HSPX constitute a heterogeneous population because some conceive easily with IVF while others do not until after surgical correction. HSPX also increases in size with ovarian stimulation, and can cause implantation failure by fluid reflux into the uterine cavity. Careful assessment of the endometrial lining is mandatory in HSPX to rule out fluid reflux from the HSPX. We present two case reports of patients whose HSPX enlarged with ovarian stimulation, causing fluid reflux into the uterine cavity which was only noted after human chorionic gonadotrophin (HCG) administration.   相似文献   
4.
Embryonally bursectomised and nonbursectomised chickens were infected with infectious bursal disease virus (IBDV) at 36 days of age. Neither clinical signs nor gross lesions were observed in the infected, bursectomised (IB) chickens. No significant changes were observed in carcass, thymus or spleen weights of IB and noninfected bursectomised chickens. A mild lymphocytic necrosis and depletion were found in the spleen, thymus and caecal tonsil of the IB chickens. Neither precipitating nor serum neutralising antibodies were detected in the sera but IBDV was reisolated from the spleen and thymus. Infected, nonbursectomised (IN) chickens developed severe depression with diarrhoea and high mortalities. Haemorrhages were found in the muscles of the breast and thigh, proventriculus and intestines. Significant changes were observed between the carcass, thymus and bursa weights of the IN and noninfected, nonbursectomised chickens. There was severe lymphatic necrosis of the bursa, thymus, spleen and caecal tonsil. Both precipitating and neutralising antibodies were detected in the sera and the virus was reisolated from the bursa, thymus and spleen. It is concluded that the bursa of Fabricius is not essential for the establishment of an IBDV infection but is required for the clinical infection.  相似文献   
5.
6.
Introduction:Human Immunodeficiency Virus (HIV) infection remains prevalent co-morbidity, and among fracture patients. Few studies have investigated the role of exercise interventions in preventing bone demineralization in people who have fractures and HIV. If exercise exposed, HIV-infected individuals may experience improved bone health outcomes (BMD), function, quality of life (QoL). The study will aim to assess the impact of home based exercises on bone mineral density, functional capacity, QoL, and some serological markers of health in HIV infection among Nigerians and South Africans.Methods and design:The study is an assessor-blinded randomized controlled trial. Patients managed with internal and external fixation for femoral shaft fracture at the study sites will be recruited to participate in the study. The participants will be recruited 2 weeks post-discharge at the follow-up clinic with the orthopaedic surgeon. The study population will consist of all persons with femoral fracture and HIV-positive and negative (HIV-positive medically confirmed) aged 18 to 60 years attending the above-named health facilities. For the HIV-positive participants, a documented positive HIV result, as well as a history of being followed-up at the HIV treatment and care center. A developed home based exercise programme will be implemented in the experimental group while the control group continues with the usual rehabilitation programme. The primary outcome measures will be function, gait, bone mineral density, physical activity, and QoL.Discussion:The proposed trial will compare the effect of a home-based physical exercise-training programme in the management of femoral fracture to the usual physiotherapy management programmes with specific outcomes of bone mineral density, function, and inflammatory markers.Trial registration:The study was prospectively registered with the Pan African Clinical Trials Registry (Reference number – PACTR201910562118957) on October 21, 2019. (https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=9425).  相似文献   
7.
8.

Background

Transmediastinal gunshot wounds are associated with a high mortality and frequently require operative intervention. The purpose of this study was to identify the diagnostic and therapeutic challenges of these injuries in a mature trauma system with decreasing prehospital time intervals.

Methods

Patients admitted to a large urban Level 1 trauma centre between 1/2006 and 12/2010 sustaining a firearm injury to the torso were identified. Transmediastinal gunshot wounds were defined as missile tracts traversing the mediastinum identified on CT images, operative notes or autopsy reports.

Results

Overall, 133 patients met study criteria. A total of 116 patients (87.2%) were haemodynamically unstable or had no vital signs on arrival to the Emergency Department. Ninety-seven (83.6%) of these patients required a resuscitative thoracotomy resulting in 8 survivors (6.0%). There were 17 haemodynamically stable patients (12.8%) identified, 14 of whom underwent CT scan evaluation. Six patients subsequently required operative intervention. Only 11 patients (8.3%) in the study population were successfully managed nonoperatively. The overall mortality was 78.9%, and for those who reached the hospital with vital signs, the mortality was 24.3%.

Conclusions

Transmediastinal gunshot wounds encountered in a mature trauma centre are highly lethal injuries requiring resuscitative thoracotomy in most instances. Changing perspectives in these injuries may reflect the effects of an evolving prehospital care.  相似文献   
9.

Introduction

Retained haemothorax (RH) is a problematic sequela of thoracic trauma, reported in up to 20% of patients following chest injury. RH is associated with a higher severity of thoracic trauma and may portend the onset of other serious post-traumatic complications, including pneumonia. The development of pneumonia has previously been reported to be as high as 19.5% in the setting of traumatic RH. The purpose of this study was to identify risk factors for the development of pneumonia as a complication in RH.

Methods

We utilized the American Association for the Surgery of Trauma Post-Traumatic Retained Haemothorax database. Patients with post-traumatic RH were prospectively enrolled from 2009 to 2011. Inclusion criteria were placement of a thoracostomy tube within 24 h of admission for the evacuation of pneumothorax or haemothorax and subsequent chest computed tomography scan chest showing RH. Patients treated with thoracotomy before placement of tube thoracostomy were excluded. For univariate analysis, the Chi-square test with Yates correction was used for comparison of categorical risk factors and the Student's t-test or the Mann–Whitney test for comparison of continuous risk factors. To identify independent risk factors for the development of pneumonia, variables from the univariate analysis significant at p < 0.2 were entered into a forward logistic regression model. Adjusted odds ratio and 95% confidence intervals (CI) were derived.

Results

328 patients with post-traumatic RH from 20 United States centres were enrolled. After stepwise regression analysis, ISS > 25 (adjusted OR: 7.1; 95% CI: 3.1, 16.4; p < 0.001), blunt mechanism of injury (adjusted OR: 3.5; 95% CI: 1.7, 7.2; p = 0.001), and failure to administer peri-procedural antibiotics on the initial thoracostomy tube placement (adjusted OR: 2.6; 95% CI: 1.30, 5.4; p = 0.01) were found to be independent predictors of the pneumonia in patients with post-traumatic RH.

Conclusions

To our knowledge, our current study is the largest attempt to identify the independent predictors for pneumonia in this population. Our data show that elevated ISS, blunt thoracic trauma, and failure to administer peri-procedural antibiotics on tube thoracostomy placement are the statistically significant independent risk factors.  相似文献   
10.
Despite increasing obesity rates in the dialysis population, obese kidney transplant candidates are still denied transplantation by many centers. We performed a single‐center retrospective analysis of a robotic‐assisted kidney transplant (RAKT) cohort from January 2009 to December 2018. A total of 239 patients were included in this analysis. The median BMI was 41.4 kg/m2, with the majority (53.1%) of patients being African American and 69.4% of organs sourced from living donors. The median surgery duration and warm ischemia times were 4.8 hours and 45 minutes respectively. Wound complications (mostly seromas and hematomas) occurred in 3.8% of patients, with 1 patient developing a surgical site infection (SSI). Seventeen (7.1%) graft failures, mostly due to acute rejection, were reported during follow‐up. Patient survival was 98% and 95%, whereas graft survival was 98% and 93%, at 1 and 3 years respectively. Similar survival statistics were obtained from patients undergoing open transplant over the same time period from the UNOS database. In conclusion, RAKT can be safely performed in obese patients with minimal SSI risk, excellent graft function, and patient outcomes comparable to national data. RAKT could improve access to kidney transplantation in obese patients due to the low surgical complication rate.  相似文献   
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