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71.
Appendicolith revealed on CT in children with suspected appendicitis: how specific is it in the diagnosis of appendicitis? 总被引:6,自引:0,他引:6
Lowe LH Penney MW Scheker LE Perez R Stein SM Heller RM Shyr Y Hernanz-Schulman M 《AJR. American journal of roentgenology》2000,175(4):981-984
OBJECTIVE. The purpose of this study was to determine the sensitivity, specificity, and positive and negative predictive values of a diagnosis of appendicitis when CT without enteric contrast material reveals an appendicolith in children with suspected appendicitis. MATERIALS AND METHODS. A retrospective review of children who underwent abdominal CT for suspected appendicitis over a 25-month period was performed to identify patients with an appendicolith. An age-matched group of patients examined for trauma served as controls. RESULTS. CT was performed in 104 children. Appendicitis was present in 60 (58%) of 104 children; 39 (65%) of 60 had an appendicolith. Appendicitis was not present in 44 (42%) of 104; six (14%) of 44 had an appendicolith. An appendicolith detected on CT had a sensitivity of 65% and a specificity of 86% for the radiologist diagnosing appendicitis. An appendicolith had a positive predictive value of 74% and a negative predictive value of 26%. Among the control population, two (3%) of 74 children had an appendicolith. This number was statistically significant compared with children in the study group with an appendicolith and abdominal pain, but without appendicitis (p = 0.02). CONCLUSION. Although an appendicolith is significantly associated with appendicitis, the detection of an isolated appendicolith on CT is not sufficiently specific to be the sole basis for the diagnosis of acute appendicitis. 相似文献
72.
SummaryWe have transfected two SV40-transformed human fibroblast cell lines with plasmids in which double-strand breaks have been introduced by restriction enzymes, within or near the selected gene. Restriction of pSV2gpt with KpnI, as previously shown by Cox et al. (1986), reduced the frequency of transfection more in the ionizing radiation-sensitive ataxia-telangiectasia line AT5BIVA than in the resistant line MRC5V1. When the related plasmid pSV2neo was restricted with SmaI, the reduction in transfection was less in the ataxia-telangiectasia than in the normal cell line. Under our conditions, the apparent defect in transfection of AT5BIVA by pSV2gpt appears to be a result of the unusual sensitivity of the repair-deficient recipient to the selective agent. Loss of potential transfectants is exacerbated when transient gene expression is reduced by restriction of the plasmid. We suggest that a reduction in yield of transfectants with restricted plasmid in ataxia-telangiectasia cells cannot readily be used as evidence of a defect in DNA repair. Our results are also relevant to standard transfection experiments, since they emphasize the importance of optimizing selection when transient expression may be reduced, to ensure that potential transfectants are not killed by the selection regime. 相似文献
73.
David Lowe Shazia Shabir John Buckels Paolo Muiesan Geoffrey Hayden Andrew Holt Ahmed Hamsho Kassi Skordilis Graham Lipkin Richard Borrows David Briggs 《Transplant immunology》2014,30(1):30-33
This case report confirms the utility of simultaneous liver transplantation in allowing successful kidney transplantation in the face of preformed, high levels of DSA, which would under normal circumstances be associated with hyperacute rejection and kidney graft failure. Antibody characterisation in terms of epitope specificity is more accurate and informative than antibodies described as “antigen-specific” and we suggest a method for identifying and tracking these antibodies; i.e. follow the epitope reaction not the antigen reactions. We consider that this will give a better insight into the behaviour and pathogenicity of HLA-specific sera. In the case presented here this approach has revealed some novel features of the post transplant antibody response in a sensitised recipient. These illustrate three phenomena which challenge current dogmas; an early resynthesis of DSA does not necessarily cause AMR, high levels of DSA can spontaneously modulate, and measurement of antibodies in terms of antigen specificity can give misleading results. 相似文献
74.
M. Patrick Lowe Saurabh Kumar Peter R. Johnson Scott A. Kamelle Donald H. Chamberlain Todd D. Tillmanns 《Journal of robotic surgery》2010,4(2):109-115
The primary aim of this article is to report the outcomes of octogenarians and nonagenarians who have undergone robotic surgery
for endometrial cancer. A multi-institutional research consortium was created to evaluate the utility of robotics for gynecologic
surgery (benign and malignant). IRB approval was obtained at each institution. A multi-institutional HIPPA compliant database
was then created and analyzed for all patients that underwent robotic-assisted surgery with staging for endometrial cancer
between the April 2003 and January 2009. In total, 395 patients were identified. A subset of patients between the ages of
80 and 95 years were then identified and analyzed for demographic data and perioperative outcomes. Twenty-seven patients in
this age group were identified who underwent robotic-assisted hysterectomy and staging. The median age was 84, and median
body mass index was 28. Comorbidities such as diabetes mellitus and hypertension were identified in 22 and 74% of patients,
respectively. Over one-half (56%) of the patients reported a prior abdominal surgery. Final pathological analysis demonstrated
that 88% of all patients had either Stage I or II disease. The median operative time was 192 min. The median estimated blood
loss was 50 cc, and the median lymph node count was 16. The median hospital stay was 1.0 day. The overall intraoperative and
postoperative complication rate was 7.4 and 33%, respectively. No patient received a blood transfusion. There was one conversion
to laparotomy (3.7%). A comparison of the outcomes of the elderly cohort to those of all patients in the database (control
group) revealed that there was no statistically significant difference between the groups in terms of operative time, blood
loss, hospital stay, nodal yield, or conversion rate. Intraoperative complications were statistically similar between the
groups; however, postoperative complications were significantly higher in the elderly cohort. We conclude that robotic surgery
is safe, feasible, and expands surgical options for octogenarians and nonagenarians diagnosed with endometrial cancer. Age
should not be considered a contraindication for robotic surgical management of patients with endometrial cancer. 相似文献
75.
76.
Inclusion body myositis is an increasingly recognised form of inflammatory myopathy with characteristic clinical and histopathological features which has seldom been reported in the United Kingdom. This paper presents the clinicopathological features of a series of patients diagnosed in Nottingham from 1986 to 1990. During this period, 1319 muscle biopsy samples were processed by this laboratory and rimmed vacuoles were seen in 17 patients. Eleven patients had definite or probable inclusion body myositis according to published criteria. The mean age of the group was 69.4 years with a male to female ratio of 8:3. Typical clinical features were a slowly progressive painless, proximal lower limb weakness, with muscle wasting and early loss of reflexes. The median duration of illness from first symptom to presentation was five years (range 2-18 years). Falls were a prominent symptom in six patients and distal weakness occurred in nine patients. Creatine kinase was increased in 10 patients but only one had a level > 1000 IU/l; the erythrocyte sedimentation rate was normal in five patients. Treatment with steroids or cytotoxic drugs, or both, did not prevent disease progression. It is confirmed that inclusion body myositis is a distinct cause of inflammatory myopathy which is probably underdiagnosed in the United Kingdom. Clinically, it should be suspected in older patients presenting with muscle weakness of insidious onset. Pathologically, a careful search should be made for rimmed vacuoles and inflammation; ultrastructurally, the presence of inclusions will confirm the diagnosis. 相似文献
77.
Ioanna Tzoulaki Gordon D Murray Amanda J Lee Ann Rumley Gordon D O Lowe F Gerald R Fowkes 《European heart journal》2007,28(3):354-362
AIMS: Recently, markers of inflammation, haemostasis, and blood rheology have received much attention as risk factors for coronary heart disease and stroke. However, their role in peripheral arterial disease (PAD) is not well established and some of them, including the pro-inflammatory cytokine interleukin-6 (IL-6), have not been examined before in prospective epidemiological studies. METHODS AND RESULTS: In the Edinburgh Artery Study, we studied the development of PAD in the general population and evaluated 17 potential blood markers as predictors of incident PAD. At baseline (1987), 1519 men and women free of PAD aged 55-74 were recruited. After 17 years, 208 subjects had developed symptomatic PAD. In analysis adjusted for cardiovascular risk factors and baseline cardiovascular disease (CVD), only C-reactive protein, fibrinogen, lipoprotein (a), and haematocrit [hazard ratio (95% CI) corresponding to an increase equal to the inter-tertile range 1.30 (1.08, 1.56), 1.16 (1.05, 1.17), 1.22 (1.04, 1.44), 1.22 (1.08, 1.38)] were significantly (P < 0.01) associated with PAD. However, these markers provided very little prognostic information for incident PAD to that obtained by cardiovascular risk factors and the ankle brachial index. Other markers including IL-6, intracellular adhesion molecule 1, d-dimer, tissue plasminogen activator antigen, and plasma and blood viscosities showed weak associations, which were considerably attenuated when CVD risk factors were accounted for. CONCLUSIONS: Our prospective data showed that several inflammatory, haemostatic, and rheological markers are associated with incident PAD; however, their clinical utility is likely to be limited. Future research is necessary to validate the importance of these biomarkers explicitly on PAD and to address the causality of the reported associations. 相似文献
78.
Huckfeldt R Redmond C Mikkelson D Finley PJ Lowe C Robertson J 《Ostomy/wound management》2008,54(10):36-41
Mediastinitis is a rare but serious postoperative complication of cardiac surgery that increases mortality rates, hospital length of stay, and medical costs. A clinical trial was conducted to investigate whether the type of postoperative surgical dressing (silver nylon or standard gauze) affects the rate of mediastinal infections. The sample consisted of 1,600 surgical cardiac patients. Infection rates in the standard gauze group (control, n = 1,235) were collected retrospectively from 24 months of infection control records. In the prospective treatment arm of the study, the wounds of all consecutive surgical patients (n = 365) were covered with a silver nylon dressing and patients were assessed during the 3-week postoperative visit. Thirteen (13) patients in the control group (1%) and none of the patients in the treatment group developed mediastinitis (chi2 [1, N = 1,600] = 3.88, P <0.05). Study findings support the need for a large, prospective, controlled clinical study to confirm the effects of these dressings on mediastinitis, resultant morbidity, and costs of care. 相似文献
79.
80.
Leng GC Papacosta O Whincup P Wannamethee G Walker M Ebrahim S Nicolaides AN Dhanjil S Griffin M Belcaro G Rumley A Lowe GD 《Atherosclerosis》2000,152(1):167-174
Most estimates of the prevalence of peripheral atherosclerosis have been based on intermittent claudication or lower limb blood flow. The aim of this study was therefore to determine the prevalence of underlying femoral plaque, and to determine its association with other cardiovascular disease and risk factors. Presence of plaque was identified using ultrasound in a random sample of men (n=417) and women (n=367) aged 56-77 years. Coexistent cardiovascular disease, exercise and smoking were determined by questionnaire, blood pressure was recorded, and serum cholesterol and plasma fibrinogen were determined. Of the 784 subjects that were scanned, 502 (64%) demonstrated atherosclerotic plaque. Disease prevalence increased significantly with age (P<0.0001), and was more common in men (67.1 vs. 59.4%, P<0.05). Subjects with femoral plaque had a significantly greater odds of previous ischaemic heart disease (OR 2. 2, 95% CI 1.3, 3.7) and angina (OR 1.7, 95% CI 1.03, 2.7), but not of stroke or leg pain on exercise. Current and ex-smoking, raised serum total cholesterol and plasma fibrinogen levels, but not blood pressure, were associated with an increased risk of femoral plaque, independent of age and sex. Frequent exercise and a high HDL cholesterol were significantly associated with lower risk. In conclusion, therefore, atherosclerotic disease of the femoral artery affects almost two-thirds of the population in late middle age. It is associated with an increased prevalence of ischaemic heart disease and angina, but whether detecting at risk individuals using ultrasound offers advantages over simpler and less expensive risk factor scoring requires evaluation in trials. 相似文献