Search

Background: Recent European multisociety guidelines recommend routine follow-up imaging of gallbladder polyps (including polyps

In the new world of work, employers are increasingly favoring flexible work arrangements in order to minimize labor costs, and technological advancements are also making it easier for corporate emp...

CEO successions represent critical junctures for firms. Although extant research explores the performance consequences resulting from different succession types, what remains underexplored is what happens when the firm rehires a former CEO (e.g., a “boomerang CEO”). Using a sample of over 6,000 CEO tenures, we examine the performance consequences of former CEOs who return to the firm. Our results suggest that these boomerang CEOs perform significantly worse than other CEOs, and that this effect is especially strong for firms in dynamic industries and when the boomerang CEO is a founder. Thus, the irony is that rehired CEOs may drag organizations backward instead of pushing them forward. Collectively, our findings contribute to the upper echelons and experience literatures.

Schemas are an important concept in organization research. While much is known about the value of schemas, explicit theoretical models of how they develop are lacking. Our study of the insurance in...

Using an inductive research logic and in-depth nested case studies, we explore how executives develop capabilities, and in particular, an internationalization capability. Results show that capabili...

UNLABELLED This study assesses the frequency of lower limb and back pain in children with Guillain-Barre syndrome and reviews the magnetic resonance imaging results of those undergoing spinal imaging. Over an 8-y period, nine children presented with various combinations of severe back pain, leg pains, impairment of gait and bladder dysfunction. Guillain-Barre syndrome was confirmed on clinical examination and peripheral electrophysiology (n = 8). Magnetic resonance imaging in four patients, following contrast injection, showed enhancement of the cauda equine and, additionally, of the cervical nerve roots in one of the patients. A further patient, who was not scanned with contrast, had abnormal thickening of the lumbar roots. Carbamazepine and steroids were effectively used for analgesia in three cases. All the patients recovered. CONCLUSION Guillain-Barre syndrome should be considered in the differential diagnosis of children presenting with back and/or leg pain. Early diagnosis ensures prompt monitoring for autonomic dysfunction and respiratory compromise.

While research suggests that organizational processes are learned from experience, surprisingly little is known about the content of what is learned and how that content is developed. Using an indu...

All the main cross-sectional anatomical imaging techniques, CT, MR and ultrasound, suffer from the same problem, that they lack specificity. Benign may be indistinguishable from malignant tumours and the appearances of infection frequently overlap those of malignant disease and vice-versa. A vast amount of data are presented in each image of a CT or MRI series and it is very easy to overlook significant involvement of nodes and organs by metastatic disease. Nodal involvement by tumour is usually assessed using the size of the nodes. This is

Accelerators are an increasingly prevalent and important part of the entrepreneurial landscape. They provide intensive mentoring and education over a short, fixed-length period with the goal of aid...

Over the last decade, dynamic capabilities (DCs) research has become a dominant topic and one of the most active research streams in management research (Helfat et al., 2007) – yet the understandin...

Phytohaemagglutinin (PHA)-induced T-cell proliferation is suppressed completely in steroid-sensitive asthma (SSA) by fluticasone propionate (FP). By contrast, in patients with steroid-resistant asthma (SRA), this proliferative response is only partially attenuated by steroids, which suggests that the T lymphocyte may harbour a key molecular defect in these patients. Both CD4+ and CD8+ T cells may be involved in orchestrating the inflammation underlying asthma. We examined whether CD4+ or CD8+ T cells isolated from SRA and SSA patients are equally susceptible to steroid suppression of PHA-induced proliferation. Complete suppression of CD4+ T-lymphocyte proliferation was seen in both SSA and control subjects at concentrations of 10(-9) M FP. In contrast, proliferation of CD4+ T cells from SRA patients was only partially inhibited, even at 10(-6) M FP. CD8+ responses from SRA, SSA and controls were all similar, with only a partial suppression of proliferation at 10(-6) M FP. Differential suppression by FP of CD4+ T cells has thus been demonstrated between SRA and SSA patients.

Sickle cell disease is the most common inherited haemoglobinopathy described. Complications of sickle cell disease (SCD) are due to chronic haemolysis of fragile red cells or secondary to vascular occlusion by sickled red cells with subsequent tissue infarction. Traditionally plain film radiography has been the mainstay in the assessment of patients with SCD, but increasingly magnetic resonance (MR) imaging and computed tomography (CT) are being used. In this review the imaging features of a range of complications of SCD are demonstrated with particular emphasis on CT and MR.

The level of dynamism within environments differs across time and across industries. These differences present firms simultaneously with problems and opportunities, and managers must learn how to r...

In the race to attract and retain a generation of employees increasingly looking for meaningful work, organizations are taking explicit action to be good corporate citizens, for instance by impleme...

Much research suggests that organizational experience plays a key role in improving outcomes. Yet, it is largely unclear how that experience should be best accumulated. We use data on repeated acqu...

AIM: To demonstrate the magnetic resonance imaging (MRI) appearances of intact and ruptured Trilucent TM implants with imaging and surgical correlation. The appearances of the implant transponder artefact are also described MATERIALS AND METHODS: A retrospective review of the MRI findings in 34 patients with bilateral subpectoral Trilucent TM breast implants (Lipomatrix, Inc./Collagen Aesthetics International Inc., Neuchatel, Switzerland) was performed. Patients under implant surveillance and those with suspected implant rupture formed the study group. Imaging findings were correlated with surgical appearances. RESULTS: Surgical correlation was available in 53% of patients. Fifty per cent (18/36) of implants were intact at surgery, 50% (18/36) of implants were ruptured. Of the 18 ruptured implants, 17 were intracapsular ruptures and one an extracapsular rupture. The sensitivity of MRI for detection of intracapsular rupture in Trilucent TM breast implants was 82% specificity 76%, positive predictive value 78%, negative predictive value 81% and accuracy 79% in this study group. No case of implant rupture was obscured by the transponder artefact. Four implants were found to have ‘pseudocapsules’ at surgery (5·9%), the implants were intact with fluid present between the implant and capsule. Only one pseudocapsule was demonstrated on MRI. CONCLUSION: Magnetic resonance imaging is currently the most accurate technique for diagnosis of implant rupture in Trilucent TM breast implants. Transponder artefact does not appear to interfere with the assseessment of implant rupture . Elson, E. M. et al . (2002). Clinical Radiology 57 , 263–267.

A fundamental challenge for new ventures is overcoming liabilities of newness - particularly, lack of business knowledge and lack of social embeddedness. Accelerators, intense, time- compressed entrepreneurial programs, attempt to alleviate these liabilities and accelerate venture development by facilitating learning and network development in new ventures. However, because of time compression diseconomies and the potential for inappropriate standardization, the literature suggests that such attempts at acceleration may be ineffective or even counterproductive. We test these competing ideas by comparing performance effects of accelerator-backed new ventures to a matched set of non–accelerator new ventures. Compared to the non-accelerator new ventures, we find that ventures backed by top accelerators are faster in raising venture capital and gaining customer traction. Intriguingly, our results also indicate that prior founder experience (e.g., prior entrepreneurial experience, formal education) is not a su...

Two cases of intussusception are reported with heterotopic pancreatic tissue attached to and draining into the ileum. The first patient, a boy aged 16 months, presented with ileoileal intussusception. The diagnosis was confirmed on ultrasound scan. Laparotomy and resection were performed. A 12-mm nodule of heterotopic pancreatic tissue was identified in the ileal serosa at the apex of the intussusceptum, fully formed with acinar tissue, islets, and draining duct. The second patient, also a boy aged 16 months, presented with obstructed ileocolic intussusception in which the lead point at surgery resembled a Meckel's diverticulum. Histopathology revealed a similar 10-mm nodule of fully formed pancreatic tissue in the ileal serosal tissues, with some acinar tissue extending through the wall of the intestine alongside ductal structures. In both cases there was ectopic gastric mucosa either in the distal part of the draining duct or in the small intestine itself at the opening. Heterotopic pancreas is a rare cause of intussusception. We propose that this lesion is of vitellointestinal tract origin, conceptually similar to a Meckel's diverticulum but without a diverticulum as such. Heterotopic pancreatic tissue occurring alone is more common in the proximal small intestine, duodenum, and stomach than in the ileum, and it is often asymptomatic.

While prior research establishes that firms learn at different rates, less is known about how some firms accelerate learning. This study uses theory building and theory elaboration methods to sugge...

Categories are a central concept in organizational research. While a growing research exists on category development, it generally overlooks the role of relational structure. In this paper, we address this gap through an inductive study of category development for manufacturing software from its origins in 1954 until 1988. We unpack category development into two key processes (formation and evolution) and find that both rely critically on the overlooked role of relations. First, we find that category formation relates to a process of unitization where relations between features form cohesive groups that become the basis of a new category. Second, we find that subsequent category evolution relates to a process of association where more centrally located categories develop more than isolated categories. At a higher level, our study has important implications for organizational theory.

A 27-year-old Caucasian male patient presented with a 4 week history of unsteadiness of gait, bilateral leg weakness, gradual loss of bladder and rectal continence and decreased visual acuity. The patient had been treated for a presumed liver abscess 2 months previously. The patient had lost 15 kg in weight over 6 months. A 666 cm lump was observed in the right occipitoparietal region on CT (Figure 1). Ophthalmoscopy revealed bilateral disc swelling. What was the diagnosis?

Much is known about the importance of building capabilities. Yet, surprisingly little is known about how multiple capabilities might be built concurrently since most existing research explores a pa...

Modern imaging methods are very important in the management of patients with cancer and of their disease. It is vital that clinicians treating them understand the relevance of different imaging techniques for specific applications, so that the best choice can be made to aid diagnosis and monitor response to treatment. This review briefly covers the development and principles of the diverse imaging methods available, from the discovery of x-rays by Rontgen in 1895 to the recent techniques of magnetic resonance and positron emission tomography. The authors endeavour to point out the strengths and weaknesses of each method, using clinical examples where appropriate. Finally, future developments are discussed. It is hoped that this review will aid clinicians diagnosing and treating cancer patients to choose the most suitable imaging method for their patients from among the vast array available.

A 65-year-old man presented with a 2 week history of an aching pain in the right loin, radiating to the back of both thighs. This pain occurred within walking 25 yards and was relieved by rest. His symptoms had started after changing a car tyre and, consequently, he attributed them to this. He had, however, also been dyspnoeic. On further questioning he had noted feeling bloated and had loosened his trouser belt by two notches. A provisional diagnosis of spinal stenosis or intermittent claudication was made and he was referred for magnetic resonance imaging (MRI) of the lumbar spine.

Eight patients are described in whom transplant lymphocoeles were drained. All had 99Tcm-DTPA dynamic renal scintigrams performed pre-operatively; five showed features of obstruction. Photon deficient areas on the scintigrams and bladder deformities were of particular value in detecting lymphocoeles.