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31.

Introduction  

The incidence and treatment of prostate cancer in male renal-transplant patients has not been extensively evaluated. With the aging of the renal-transplant population, the diagnosis and management of prostate cancer in these patients needs further evaluation.  相似文献   
32.
ObjectivesTo study the potential factors include gene mutation, efflux pump and alteration of permeability associated with quinolone-resistance of Salmonella enterica strains isolated from patients with acute gastroenteritis and to evaluate the degree of synergistic activity of efflux pump inhibitors when combined with ciprofloxacin against resistant isolates.MethodsAntimicrobial resistance patterns of fifty-eight Salmonella isolates were tested. Five isolates were selected to study the mechanism of resistance associated with quinolone group, including mutation in topoisomerase-encoding gene, altered cell permeability, and expression of an active efflux system. In addition, the combination between antibiotics and efflux pump inhibitors to overcome the microbial resistance was evaluated.ResultsFive Salmonella isolates totally resistant to all quinolones were studied. All isolates showed alterations in outer membrane proteins including disappearance of some or all of these proteins (Omp-A, Omp-C, Omp-D and Omp-F). Minimum inhibitory concentration values of ciprofloxacin were determined in the presence/absence of the efflux pump inhibitors: carbonyl cyanide m-chlorophenylhydrazone, norepinephrin and trimethoprim. Minimum inhibitory concentration values for two of the isolates were 2–4 fold lower with the addition of efflux pump inhibitors. All five Salmonella isolates were amplified for gyrA and parC genes and only two isolates were sequenced. S. Enteritidis 22 had double mutations at codon 83 and 87 in addition to three mutations at parC at codons 67, 76 and 80 whereas S. Typhimurium 57 had three mutations at codons 83, 87 and 119, but no mutations at parC.ConclusionsEfflux pump inhibitors may inhibit the major AcrAB-TolC in Salmonella efflux systems which are the major efflux pumps responsible for multidrug resistance in Gram-negative clinical isolates.  相似文献   
33.
Because of its ability to depict intravascular, intramural, and extramural pathology, non-invasive imaging is well suited to assessing life-threatening hemoptysis that may complicate Beh?et disease. We made exclusive use of CT angiography supplemented by MR to identify pulmonary thromboembolism, mediastinal lymphadenopathy, and bilateral pulmonary artery aneurysms with signs of previous unilateral rupture. Two-dimensional reformatted CT images provided surgeons with a road map of upstream and downstream vascular relationships prior to aneurysm resection. Imaging findings were confirmed by surgery and pathology. Non-invasive imaging proved to be a useful alternative to standard catheter arteriography in the preoperative assessment of hemoptysis in this patient with Beh?et disease. Received 2 April 1997; Revision received 20 June 1997; Accepted 1 September 1997  相似文献   
34.
We performed limb lengthening and correction of deformity of nine long bones of the lower limb in six children (mean age, 14.7 years) with osteogenesis imperfecta (OI). All had femoral lengthening and three also had ipsilateral tibial lengthening. Angular deformities were corrected simultaneously. Five limb segments were treated using a monolateral external fixator and four with the Ilizarov frame. In three children, lengthening was done over previously inserted femoral intramedullary rods. The mean lengthening achieved was 6.26 cm (mean healing index, 33.25 days/cm). Significant complications included one deep infection, one fracture of the femur and one anterior angulation deformity of the tibia. The abnormal bone of OI tolerated the external fixators throughout the period of lengthening without any episodes of migration of wires or pins through the soft bone. The regenerate bone formed within the time which is normally expected in limb-lengthening procedures performed for other conditions. We conclude that despite the abnormal bone characteristics, distraction osteogenesis to correct limb-length discrepancy and angular deformity can be performed safely in children with OI.  相似文献   
35.

Purpose

The purpose of this study was to determine the correlation between the Western Ontario and McMasters Universities Osteoarthritis Index (WOMAC) and Knee Injury Osteoarthritis Outcomes scores (KOOS) and the degree of tibiofemoral cartilage loss on plain radiography and 3T magnetic resonance imaging (MRI). We hypothesize that these subjective outcome scores will have a significant correlation to quantitative joint space loss.

Methods

Data used in the preparation of this article were obtained from the osteoarthritis initiative (OAI) database (OAI public use data sets kMRI_QCart_Eckstein18 and kXR_QJSW_Duryea16). Four hundred and forty-five patients had WOMAC/KOOS scores, quantitative tibiofemoral joints space width on plain radiographs and quantitative tibiofemoral cartilage thickness and per cent full thickness cartilage loss on 3T MRI. Joint space width on plain radiographs was correlated to cartilage thickness on MRI, and WOMAC/KOOS scores were correlated to the degree of cartilage loss using Pearson correlation coefficients.

Results

There was a statistically significant correlation between medial and lateral compartment cartilage thickness on MRI and medial and lateral joint space width on plain radiography (r = 0.86, r = 0.80) (p < 0.001). KOOS knee pain score was significantly correlated to increasing per cent full thickness cartilage loss in the medial femoral compartment (r = 0.34) (p < 0.001). KOOS symptom score was significantly correlated to decreasing joint space width in the medial (r = 0.16) and lateral (r = 0.15) compartment and increasing per cent full thickness cartilage loss in the medial femoral compartment (r = 0.36) (p < 0.001). No WOMAC score was correlated to degree of joint space width, cartilage thickness or per cent full thickness cartilage loss (n.s).

Conclusion

The WOMAC and KOOS scores are poor indicators of tibiofemoral cartilage loss, with only the KOOS symptom and knee pain score being weakly correlated. Osteoarthritis is a multifactorial process and the need to treat patients based off their symptoms and rely on radiographs as confirmatory modalities, and not diagnostic modalities, when talking about OA and medical intervention.

Level of evidence

Level 2.  相似文献   
36.

Background

The objective of this study was to assess Canadian general surgeons’ knowledge of bariatric surgery and perceived availability of resources to manage bariatric surgery patients.

Methods

A self-administered questionnaire was developed using a focus group of general surgeons. The questionnaire was distributed at two large general surgery conferences in September and November 2012. The survey was also disseminated via membership association electronic newsletters in November and December 2012.

Results

One hundred sixty-seven questionnaires were completed (104 practicing surgeons, 63 general surgery trainees). Twenty respondents were bariatric surgeons. Among 84 non-bariatric surgeons, 68.3 % referred a patient in the last year for bariatric surgery, 79 % agreed that bariatric surgery resulted in sustained weight loss, and 81.7 % would consider referring a family member. Knowledge gaps were identified in estimates of mortality and morbidity associated with bariatric procedures. The majority of surgeons surveyed have encountered patients with complications from bariatric surgery in the last year. Over 50 % of surgeons who do not perform bariatric procedures reported not feeling confident to manage complications, 35.4 % reported having adequate resources and equipment to manage morbidly obese patients, and few are able to transfer patients to a bariatric center. Of the respondents, 73.3 % reported residency training provided inadequate exposure to bariatric surgery, and 85.3 % felt that additional continuing medical education resources would be useful.

Conclusions

There appears to be support for bariatric surgery among Canadian general surgeons participating in this survey. Knowledge gaps identified indicate the need for more education and resources to support general surgeons managing bariatric surgical patients.
  相似文献   
37.
Objective: To mechanically test the intact cardiac structure to determine the sequence of contraction within the myocardial mass to try to explain ejection and suction. Methods: In 24 pigs (30–85 kg), segment shortening at the site of sonomicrometer crystals was continuously recorded. The ECG evaluated rhythm, and Millar pressure transducers measured intraventricular pressure and dP/dt. Results: Study of segment shortening defined a sequence of contraction within the myocardial mass, starting at the free wall of the right ventricle and on the endocardial side of the antero-septal wall of the left. Crystal location defined underlying contractile trajectory; transverse in right ventricle followed by basal posterior left ventricle, and from the endocardial anterior wall to the posterior apical segment and finally to the epicardial side of the anterior wall. Mean shortening fraction averaged 18±3%, with endocardial exceeding epicardial shortening by 5±1%. Epicardial segment crystal displacement followed endocardial shortening by 82±23 ms in the anterior wall, and finished 92±33 ms after endocardial shortening stopped, time frame that matches the interval of fast drop of ventricular pressure and the start of suction. Conclusions: Crystal shortening fraction sequence followed the rope-like myocardial band model to contradict traditional thinking, with two starting points of excitation–contraction, the right anterior free wall of the right ventricle, and the endocardial side of the anterior wall. Active suction may be due to active shortening of the epicardial fibers of the anterior wall, because relaxation was not detected when both mitral and aortic valves were closed during the interval previously termed ‘isovolumetric relaxation’.  相似文献   
38.
BACKGROUND: Most of the recent reports on the surgical management of parotid gland disorders come from specialist divisions of otolaryngology, head and neck, or faciomaxillary surgery. The aim of the present study was to evaluate the outcome of surgery for parotid tumours in a general surgical unit of a teaching hospital. METHOD: A prospective clinicopathological study was undertaken over a 5-year period for consecutive patients operated on for parotid gland tumours in the King Saud University Unit of Riyadh Medical Complex. Parameters analyzed were demographic details, clinical presentation, diagnostic work-up, type of surgery, and outcome in terms of early and late morbidity. RESULTS: Thirty seven parotid operations were performed on 36 consecutive patients. All patients presented with parotid gland swelling. Mean age was 51.6 years with a male preponderance. Fine-needle aspiration diagnosed the pathology in 33 out of 37 lesions. Pleomorphic adenoma was the commonest pathology observed in 24 patients (64.9%). Warthin's tumour was more common among male patients and was the only pathology with bilateral involvement. Malignant tumour was found in five patients (13.5%). Superficial conservative parotidectomy was the most frequently performed operation (84%). Overall postoperative morbidity was 13.5%. Transient facial nerve palsy was observed in seven cases (19%). There was no recurrence identified in patients with benign diseases during the mean follow up of 38.5 months. CONCLUSION: Parotid gland surgery can still be performed in a general surgery unit with comparable outcome. However, the operation should be performed in units with special interest and experience in surgery for parotid gland disorders.  相似文献   
39.

Purpose

Esophageal atresia (EA) with tracheoesophageal fistula (TEF) type C accounts for 85% of all EA. In our center, patients were previously started on total parenteral nutrition (TPN) postoperatively and oral feedings initiated only after a contrast esophagogram. Our aim is to assess the benefit of intraoperatively placed transanastomotic feeding tubes (TAFTs).

Methods

A 7-year retrospective review analyzed the outcomes of children with EATEF type C as they relate to the use of TAFT. Demographics, associated anomalies, operative findings, complications, duration of TPN, resumption of oral feeding, length of stay, and follow-up were examined.

Results

Twenty-one patients had EATEF type C. Eleven (55%) and 9 (45%) patients were identified as nonfeeding tube (NFT) and TAFT groups, respectively. There were no differences in gestational age, birth weight, associated anomalies, and interval to operative intervention or operative time. Excluding one patient with a severe cardiac malformation in the NFT group, there were no significant differences in anastomotic leak (8% vs 22%), stenosis (36% vs 22%), TPN duration (20 days vs 12 days), and cholestasis (36% vs 11%).

Conclusion

Transanastomotic feeding tube may lead to shorter TPN duration and decreased cholestasis, but a larger prospective study would be required to prove these benefits and ensure that it does not increase anastomotic leaks. This could be done through an expanded Canadian Pediatric Surgery Network study.  相似文献   
40.
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