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排序方式: 共有1754条查询结果,搜索用时 15 毫秒
61.
62.
Mewissen MW; Erickson SJ; Foley WD; Lipchik EO; Olson DL; McCann KM; Schreiber ER 《Radiology》1989,173(1):155-157
Color Doppler flow imaging or compression ultrasound (US) was used to prospectively determine frequency of thrombosis at 54 venous insertion sites (47 in common femoral veins, seven in right internal jugular veins) after percutaneous placement of Greenfield filters for interruption of the inferior vena cava. Fifty-one filters were successfully placed in 51 patients with a dilator set or a balloon angioplasty catheter. Nine focal thrombi were detected in the common femoral vein (19%) and one in the right internal jugular vein (14%). Use of dilators induced eight thrombi (24%), compared with two (10%) from balloon catheters. The left common femoral vein had a high frequency of thrombosis, regardless of dilation technique (five of nine). Of nine patients with acute common femoral vein thrombosis, four became symptomatic within 10 days after the procedure. Patients may remain asymptomatic or have delayed symptoms; thus, US is valuable for determining patients at risk of thrombosis of the common femoral vein. 相似文献
63.
Symons NR Purkayastha S Dillemans B Athanasiou T Hanna GB Darzi A Zacharakis E 《American journal of surgery》2011,(3):336-343
Background
Laparoscopic antireflux surgery is an accepted treatment for persistent gastroesophageal reflux but about 4% of patients will eventually require revision surgery.Methods
We searched The Cochrane Collaboration, Medline, and EMBASE databases, augmented by Google Scholar and PubMed related articles from January 1, 1990, to November 22, 2010. Twenty studies met the inclusion criteria, reporting on 930 surgeries.Results
The mean surgical duration was 166 minutes and conversion to open revision fundoplication was required in 7% of cases. Complications were reported in 14% of cases and the mean length of stay varied between 1.2 and 6 days. A good to excellent result was reported for 84% of surgeries and 5% of patients required a further revisional procedure.Conclusions
Laparoscopic revision antireflux surgery appears to be feasible and safe, but subject to somewhat greater risk of conversion, higher morbidity, longer hospital stay, and poorer outcomes than primary laparoscopic fundoplication. 相似文献64.
Quantification of carotid stenosis on CT angiography 总被引:6,自引:0,他引:6
PURPOSE: Carotid artery stenosis quantification uses percent diameter ratios from conventional angiography. Multidetector high-speed CT angiography (CTA) allows direct millimeter measurement of carotid stenosis. We hypothesize a linear relationship between millimeter stenosis measurements and derived percent, alleviating cumbersome ratio calculations. METHODS: Two neuroradiologists separately reviewed CTAs of 268 carotid arteries, blinded to other information. The narrowest portion of each carotid stenosis was measured in millimeters from axial source images. Distal internal carotid arteries (ICAs) were measured beyond the bulb, where walls are parallel. North American Symptomatic Carotid Endarterectomy Trial (NASCET)-style ratios were calculated for each ICA, except for suspected near-occlusions. Interobserver agreement was calculated for all measurements. Correlation coefficients were calculated comparing millimeter and derived percent stenosis, followed by regression analysis. Sensitivity and specificity values tested validity. RESULTS: Interobserver agreement correlations were excellent, from 0.78 to 0.89 (2-tailed P = .01). Excellent reader correlation permitted averaging of millimeter stenosis and distal ICA measurements, which were then used to calculate mean percent stenosis. Stenosis assessment was confidently performed from source images even with calcification. Regression analysis of mean percent as a function of mean millimeter stenosis shows a linear relationship, correlating 1.3 mm to 70% and 2.2 mm to 50% NASCET-style stenosis (Pearson's correlation of -0.95; n = 136). Direct millimeter measurement defining severe stenosis (70% or greater) has sensitivity of 88.2%, specificity of 92.4%, and negative predicted value of 98.2%. CONCLUSION: There is a linear relationship between millimeter carotid stenosis diameter and derived percent stenosis. This allows prediction of NASCET-type percent from millimeter stenosis. 相似文献
65.
HL Robbins M Hetzel S Mungall SJ Cawthorn 《Annals of the Royal College of Surgeons of England》2015,97(1):e1-e2
Tuberculous mastitis is rare, especially in Western countries. We describe a case where the interferon gamma release assay blood test led to diagnosis and successful treatment of the disease. 相似文献
66.
A. M. Aiken J. B. Haddow N. R. A. Symons S. Kaptanis A. C. Katz-Summercorn D. Debnath H. Dent S. Tayeh V. Kung S. Clark J. Gahir S. Dindyal S. Farag A. Lazaridis C. P. Bretherton S. Williams A. Currie H. West J. Davies S. Arora A. Kheraj B. M. Stubbs N. Yassin S. Mallappa G. Garrett S. Hislop A. Bhangu Y. Abbey I. Al-Shoek U. Ahmad G. Sharp A. Memarzadeh A. Patel F. Ali H. Kaderbhai C. H. Knowles 《Hernia》2013,17(5):657-664
Purpose
Evidence regarding whether or not antibiotic prophylaxis is beneficial in preventing post-operative surgical site infection in adult inguinal hernia repair is conflicting. A recent Cochrane review based on 17 randomised trials did not reach a conclusion on this subject. This study aimed to describe the current practice and determine whether clinical equipoise is prevalent.Methods
Surgeons in training were recruited to administer the Survey of Hernia Antibiotic Prophylaxis usE survey to consultant-level general surgeons in London and the south-east of England on their practices and beliefs regarding antibiotic prophylaxis in adult elective inguinal hernia repair. Local prophylaxis guidelines for the participating hospital sites were also determined.Results
The study was conducted at 34 different sites and received completed surveys from 229 out of a possible 245 surgeons, a 93 % response rate. Overall, a large majority of hospital guidelines (22/28) and surgeons’ personal beliefs (192/229, 84 %) supported the use of single-dose pre-operative intravenous antibiotic prophylaxis in inguinal hernia repair, although there was considerable variation in the regimens in use. The most widely used regimen was intravenous co-amoxiclav (1.2 g). Less than half of surgeons were adherent to their own hospital antibiotic guidelines for this procedure, although many incorrectly believed that they were following these.Conclusion
In the south-east of England, there is a strong majority of surgical opinion in favour of the use of antibiotic prophylaxis in this procedure. It is therefore likely to be extremely difficult to conduct further randomised studies in the UK to support or refute the effectiveness of prophylaxis in this commonly performed procedure. 相似文献67.
A foot-pad oedema model was used to investigate the presence of free radicals using a chemiluminescence method. This model is an example of a cell mediated hypersensitivity reaction. Male rats were inoculated in the scruff with Freund's Complete Adjuvant (FCA) on Day 0 and then challenged 6 days later with FCA in one hind paw. An acute inflammatory reaction was initiated over the following 96 hours and within 4 hours of induction, reactive oxygen species were detected in the inflamed tissue. A peak of chemiluminescence activity was seen 8 hours after the induction of the inflammatory reaction, well before maximum oedema was observed. Using mannitol, catalase and DABCO to elucidate the nature of the reactive oxygen species it was found that hydroxyl radicals, hydrogen peroxide and singlet oxygen all contributed to this burst of oxidative activity and are therefore probably involved with the process of lipid peroxidation and the severity of an inflammatory reaction. 相似文献
68.
69.
von der Mohlen MA; van Deventer SJ; Levi M; van den Ende B; Wedel NI; Nelson BJ; Friedmann N; ten Cate JW 《Blood》1995,85(12):3437-3443
A recombinant endotoxin-neutralizing protein, rBPI23, was shown to partially prevent endotoxin-induced activation of the fibrinolytic and coagulation systems in experimental endotoxemia in humans. In a placebo- controlled, blinded crossover study, eight volunteers were challenged twice with an intravenous bolus injection of endotoxin (40 EU/kg of body weight) and concurrently received either rBPI23 (1 mg/kg) or placebo (human serum albumin, 0.2 mg/kg). rBPI23 treatment significantly lowered the endotoxin-induced fibrinolytic response, ie, reduced the release of tissue-type plasminogen activator, urokinase- type plasminogen activator, plasminogen activator inhibitor antigen, and complex formation of plasmin alpha 2-antiplasmin (P = .0078 for each). Plasminogen activator inhibitor activity was also reduced, but not significantly according to the Hochberg method (P = .0304). The endotoxin-induced activation of the procoagulant state as reflected by increase in F1 + 2 fragments and TAT complexes was blunted by rBPI23 infusion (P = .0391 [not significant according to the Hochberg method] and .0078, respectively). These results indicate that rBPI23 is capable of reducing both the activation of the fibrinolytic and the coagulation systems after low-dose endotoxin infusion in humans. 相似文献
70.
Wolff JJ Clary J Clay J Harper VN Bodfish JW Symons FJ 《American journal on intellectual and developmental disabilities》2012,117(3):225-232
Patterns of caregiver responses to client adaptive behavior were compared between adults with intellectual disabilities with and without self-injurious behavior. Participants with moderate to profound intellectual disability and self-injury (n=89) and age/IQ matched control participants (n=20) were selected from a large sample of adults living in a regional residential center. Approximately 45 minutes of direct observation data were collected for each participant during unstructured leisure time. Data were sequentially analyzed and Yule's Q scores derived and compared among groups. Results indicated that caregivers were more responsive to prosocial initiations and adaptive engagement among individuals with severe self-injurious behavior than to those with mild or no self-injurious behavior and that these responses were more likely to be in the form of a demand. 相似文献