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71.
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   
72.
73.
PURPOSE OF THE STUDY: Atrial fibrillation after cardiac surgery is still a frequent encountered complication and has been associated with increased hospital length of stay and numerous postoperative complications. The pathogenesis of atrial fibrillation involves an overall sequence of perioperative events, collectively termed as ischemia-reperfusion injury. Heat-shock proteins have been found to provide increased protection during ischemia-reperfusion as well as increased postischemic cardiac functional recovery. We sought to determine whether preoperative atrial heat shock levels were correlated with the appearance of postoperative atrial fibrillation. BASIC METHODS: Preoperative atrial myocardial samples obtained just before cannulation from 101 patients were used to detect immunohistochemically the expression of heat-shock proteins. The derived results were compared statistically with the incidence of postoperative atrial fibrillation, its time of appearance, duration and resistance to administered antiarrhythmics. PRINCIPAL FINDINGS: The overall incidence of postoperative atrial fibrillation was 22.3%. Of these patients, 58.3% had no detectable heat shock proteins in their cytoplasm, in sharp contrast with 100% of the patients with no atrial fibrillation who were positive for heat shock proteins (p<0.01). Four percent of our patient group had prolonged atrial fibrillation (defined as duration >48 h). These patients had significantly less (p<0.01) nuclear heat shock protein expression compared with the non-atrial fibrillation group. However, the difference of the heat shock protein expression between the prolonged atrial fibrillation and the rest of the atrial fibrillation patients was not significant (p=0.891). CONCLUSIONS: Our results indicate that patients with low preoperative atrial heat shock protein expression have a significantly greater incidence of postoperative atrial fibrillation. Heat shock protein expression did not, however, correlate with the onset of atrial fibrillation and the resistance to administered medications. Heat shock protein preoperative induction as a measure of myocardial preconditioning may potentially decrease the incidence of postoperative atrial fibrillation.  相似文献   
74.

Background

Burns are one of the most significant health problems throughout the world, leading to prolonged hospitalisation and hence increased expense for the patients, their families and society. Today, the prognosis of patients with burns is dependent, apart from adequate treatment, upon the health-care system and health-care professionals, regarding not only survival, but also lifelong quality of life. This study aims to assess quality of life of adult patients with severe burns.

Patients and methods

This study was conducted on 100 adult patients with severe burns in the burn outpatient clinic (male and female) at Mansoura University Hospital. Parameters of burn and Burn Specific Health Scale (BSHS-B) were used to assess quality of life following burns.

Results

The study revealed that burns has negative impact on most dimensions of the quality of life of patients with burns.

Conclusions

The quality of life for people who have sustained a burns should be recognised and valued by the burn team in all phases of burn care.  相似文献   
75.

Introduction  

The gold standard for treating transverse olecranon fractures is tension band fixation. A problem with this technique is migration of the K-wires leading to premature hardware removal. The aim of this study is to compare stability provided by two new techniques designed to eliminate the problem with backing out of K-wires, with that of the recommended tension band technique, performed with a biomechanical in vitro investigation. Our hypothesis was that the two new techniques would provide at least equal stability as the traditional tension band fixation.  相似文献   
76.

Purpose

This study was designed to develop a prognostic factor for fetuses with sacrococcygeal teratoma (SCT) that may be useful to predict outcome and guide counseling early in pregnancy. We hypothesize that, in fetuses with SCT, the ratio of tumor size to estimated fetal weight in the second trimester predicts outcome.

Methods

We retrospectively reviewed charts of all patients evaluated at our Fetal Center for SCT between 2004 and 2009. Estimated fetal weight and tumor volume were calculated based on prenatal ultrasound or fetal magnetic resonance imaging. Patients were stratified based on tumor volume to fetal weight ratio (TFR), and their outcomes were analyzed by Fisher's Exact test.

Results

Tumor volume to fetal weight ratio before 24 weeks' gestation was predictive of outcome. Those with a TFR less than or equal to 0.12 (n = 5) had a significantly better outcome than patients with a TFR greater than 0.12 (n = 5, P < .05). All patients with poor outcomes had a TFR greater than 0.12 by 24 weeks' gestation. A TFR greater than 0.12 predicted poor outcome with 100% sensitivity and 83% specificity. All 4 patients who developed hydrops had a TFR greater than 0.12.

Conclusion

In our series of fetuses with SCT, TFR before 24 weeks' gestation correlates with outcome. This novel, prenatal diagnostic tool may be useful in prenatal counseling and for early identification of high-risk fetuses.  相似文献   
77.
The local fasciocutaneous flap has the advantage of low donor site morbidity when used for the coverage of lower limb defects. However, flap reliability remains a major problem with its use. Perforator flaps are indicated for several clinical problems. The versatility of the perforator flap makes it ideal for the reconstruction of extremities. Between September 2007 and November 2010, 34 skin perforator flaps were raised in 33 cases. Flaps which were executed as peroneal artery flaps were 13, 0.16 flaps were raised as posterior tibial artery perforator flaps, and 5 flaps as medial sural medial gastrocnemius muscle perforator skin flap. A segmental perforator was dissected and retained. Thirty-two flaps survived completely and none exhibited venous compromise. In one patient, flap was lost completely and the other showed partial tip necrosis. Complicated flaps were responded to conservative treatment. Skin perforator flap represents a technical advancement over conventional lower limb skin flaps because of its improved vascularity. It provides the surgeon with additional reconstructive options in reconstruction of difficult areas and injuries of leg. Clinical judgment is essential to assess the potential vascular territory of the flap.  相似文献   
78.
Between 1998 and 2007, a pronator quadratus pedicled bone graft was performed for 45 patients of ununited scaphoid fracture. One of them had bilateral ununited scaphoid fracture. There were 29 men and 16 women with a median age at operation of 24 (16-32) years. The affected side was the right side (dominant hand) in 32 patients whereas 13 patients had fracture of the nondominant left side. There had been 32 proximal pseudoarthrosis (through or proximal to the junction of the proximal and middle thirds of the bone) and 14 of the middle third of the scaphoid. The original fractures were caused by motor cycle accidents in 23 patients, falling on outstretched hand in 15 patients, and sport injuries in the remaining 7 patients. Surgery was indicated from 5 months to 6 years after injury (average 43 months) because of complaints of pain on heavy work. The fracture has been missed at the initial examination in 23 patients whereas cast immobilization was done for 6 weeks and 3 months in 15 and 7 cases, respectively, that had failed to result in union. There were no preoperative osteoarthritic changes, but in 25 cases, there were avascular necrosis of the proximal fragment of the scaphoid. Forty-three patients showed radiographic union after an average of 14 weeks (12-16 weeks). One patient had dislodgement of the graft and refused to do it again. The average range of movement of wrist improved after operation. Taken as a percentage of the normal range, dorsiflexion increased from 69% to 80%, palmar flexion from 66% to 76%, radial deviation from 45% to 70%, and ulnar deviation from 67% to 84%. Grip strength improved from 82% to 92% of normal. All the patients have been able to return to their former activities with no pain.  相似文献   
79.
We compare the effects of estrogen and/or ghrelin on vascular counts and collagen I/III ratio of urethral and anal canal submucosa in old vs young-adult ovariectomized rats. Ovariectomized Fisher 344 rats (18 and 3 months old, n = 24 x 2) received 42 daily intraperitoneal 17-ss estradiol (10 microg/kg), ghrelin (2 microg/kg), both, or vehicle (n = 6 x 4 per group). Blood vessel counts and collagen I/III ratio were measured, respectively, by light microscopy and Western blot analysis with immunohistochemistry of ghrelin receptors. Estrogen significantly increased urethral and anal vascular counts and collagen I/III ratio in young-adult rats. In old rats, only combined estrogen/ghrelin administration significantly increased both variables. This was not observed with estrogen or ghrelin separately. Ghrelin receptors were immunostained in urethral and anal submucosa of all samples. Combined estrogen/ghrelin administration restored postovariectomy urethral and anal canal submucosal vessel number and collagen I/III ratio in old rats suggesting independent ageing effect.  相似文献   
80.
BACKGROUND: Tyrosine kinase inhibitors have been shown to have marked clinical efficacy in patients with unresectable or metastatic gastrointestinal stromal tumors (GIST). We performed a comparative and prognostic analysis of our experience with surgically managed GIST to determine factors associated with adverse oncologic outcomes. METHODS: Oncologic outcomes of 191 patients with primary GIST surgically managed between 1978 and 2004 at a single institution were reviewed. Prognostic factors were analyzed by Cox analysis (hazard ratio [HR] and 95% confidence interval [95% CI]) and included age, sex, disease presentation (asymptomatic vs. symptomatic), tumor site (stomach, small bowel, colorectal), disease extent (localized vs. metastatic) and risk levels (high, intermediate, low, very-low) assigned on the basis of size and number of mitoses according to current National Institutes of Health recommendations. Primary end points were disease-free survival (DFS) and disease-specific survival (DSS). RESULTS: A total of 186 patients (97%) had c-kit-positive GIST. There were 54% high, 22% intermediate, 18% low, and 8% very low risk GIST originating from the stomach (54%), small bowel (36%), and colon and rectum (10%). Median patient age was 65 (range, 13-91) years, and 108 subjects (57%) were male. Seventy-two percent of patients had symptomatic local disease, and 21% patients had synchronous metastases. Most (95%) underwent R0 resections of their primary tumor. Among 146 patients (76%) with localized disease at presentation undergoing R0 resection, the 5-year DFS was 65%. High-risk GIST (HR 12, 95% CI, 5-32, P < .0001), symptomatic presentation (HR 2.5, 95% CI, 1.1-6, P = .04), and GIST in the small bowel (HR 2.8, 95% CI, 1-5, P = .003) were independently associated with decreased DFS. After a median follow-up of 63 months among survivors, the 5-year DSS was 68%. High-risk disease (HR 14.3, 95% CI, 5-41, P < .0001), symptomatic presentation (HR 3.1, 95% CI, 1.2-7.9, P = .02), and GIST in the small bowel (2.6,3 95% CI, 1-5, P = .006) were independently associated with decreased DSS. CONCLUSIONS: High-risk GIST are associated with increased disease recurrence and decreased survival despite complete surgical resection. These patients should receive adjuvant therapy in the form of tyrosine kinase inhibitors.  相似文献   
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