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1.
Management of post-cholecystectomy bile duct strictures can be complex.Traditional treatment has been surgical reconstruction. In recent years endoscopic stenting has been successful in a selected subgroup of patients with iatrogenic bile duct strictures. Adequate information about long-term results of endoscopic stenting as definite treatment for such strictures is still awaited. Surgery is a reliable and time-tested method and results of numerous studies show its long-term success in relieving biliary obstruction with minimal morbidity.  相似文献   
2.
Using in vivo-induced antigen technology (IVIAT), a modified immunoscreening technique that circumvents the need for animal models, we directly identified immunogenic Escherichia coli O157:H7 (O157) proteins expressed either specifically during human infection but not during growth under standard laboratory conditions or at significantly higher levels in vivo than in vitro. IVIAT identified 223 O157 proteins expressed during human infection, several of which were unique to this study. These in vivo-induced (ivi) proteins, encoded by ivi genes, mapped to the backbone, O islands (OIs), and pO157. Lack of in vitro expression of O157-specific ivi proteins was confirmed by proteomic analysis of a mid-exponential-phase culture of E. coli O157 grown in LB broth. Because ivi proteins are expressed in response to specific cues during infection and might help pathogens adapt to and counter hostile in vivo environments, those identified in this study are potential targets for drug and vaccine development. Also, such proteins may be exploited as markers of O157 infection in stool specimens.  相似文献   
3.
The isolation and characterization of Escherichia coli O157:H7 and non-O157 Shiga toxin-producing E. coli (STEC) strains from sheep are described. One flock was investigated for E. coli O157:H7 over a 16-month period that spanned two summer and two autumn seasons. Variation in the occurrence of E. coli O157:H7-positive sheep was observed, with animals being culture positive only in the summer months but not in the spring, autumn, or winter. E. coli O157:H7 isolates were distinguished by pulsed-field gel electrophoresis (PFGE) of chromosomal DNA and toxin gene restriction fragment length polymorphism (RFLP) analysis. Ten PFGE patterns and five RFLP patterns, identified among the isolates, showed that multiple E. coli O157:H7 strains were isolated from one flock, that a single animal simultaneously shed multiple E. coli O157:H7 strains, and that the strains shed by individuals changed over time. E. coli O157:H7 was isolated only by selective enrichment culture off 10 g of ovine feces. In contrast, strains of eight STEC serotypes other than O157:H7 were cultured from feces of sheep from a separate flock without enrichment. The predominant non-O157 STEC serotype found was O91:NM (NM indicates nonmotile), and others included O128:NM, O88:NM, O6:H49, and O5:NM. Irrespective of serotype, 98% of the ovine STEC isolates possessed various combinations of the virulence-associated genes for Shiga toxin(s) and the attaching-and-effacing lesion (stx1, stx2, and eae), suggesting their potential for human pathogenicity. The most common toxin-eae genotype was positive for stx1, stx2, and eae. A Vero cell cytotoxicity assay demonstrated that 90% of the representative STEC isolates tested expressed the toxin gene. The report demonstrates that sheep transiently shed a variety of STEC strains, including E. coli O157:H7, that have potential as human pathogens.  相似文献   
4.
The present study examines the influence of denervation on the regenerative ability of skeletal muscle in rats. Muscle denervation was achieved by transecting and ligating the cut ends of the sciatic nerve. Four to 48 weeks after denervation, the extensor digitorum longus (EDL) muscle was autotransplanted to induce muscle regeneration. The transplanted EDL muscles were examined at 1–12 weeks. Normal (i.e., no prior denervation) EDL muscle autotransplants were also examined for comparison. Denervation resulted in progressive atrophy of muscle, marked by a reduction in the size of myofibers and an increase in endomysialperimysial connective tissue. In spite of these alterations, typical events of muscle regeneration were invariably observed after transplantation. Initial myofiber degeneration and subsequent regeneration of myotubes occurred in a manner similar to normal muscle transplants. However, only a partial maturation of myotubes was observed in denervated muscles. These results show that extended denervation does not abolish the capability for muscle regeneration. The precursor myosatellite cells, proposed to be responsible for muscle regeneration, retain their regenerative potential after denervation. It is concluded, however, that the presence of intact innervation is crucial for the terminal differentation and maturation of regenerating muscle.  相似文献   
5.
Death with a functioning graft and death‐censored renal allograft failure remain major problems for which effective preventative protocols are lacking. The retrospective cohort study aimed to determine whether histologic changes on a 5‐year surveillance kidney biopsy predict adverse outcomes after transplantation in recipients who had: both Type 2 diabetes (T2DM) and obesity (BMI ≥ 30 kg/m2) at the time of transplantation (T2DM/Obesity, n = 75); neither (No T2DM/No obesity, n = 78); No T2DM/Obesity (n = 41), and T2DM/No obesity (n = 47). On 5‐year biopsies, moderate‐to‐severe mesangial expansion was more common in the T2DM/Obesity group (Banff mm score ≥2 = 49.3%; Tervaert classification MS ≥ 2b = 26.7%) compared to the other groups (p < .001 for both scores). Risk factors included older age, higher BMI, HbA1C, and triglycerides at 1‐year post‐transplant. Moderate‐to‐severe mesangial expansion correlated with death with function (HR 1.74 (1.01, 2.98), p = .045 Banff and 1.89 (1.01, 3.51) p = .045 Tervaert) and with death‐censored graft loss (HR 3.2 (1.2, 8.8), p = .02 Banff and HR 3.8 (1.3, 11.5), p = .01 Tervaert) over a mean of 11.6 years of recipient follow‐up post‐transplant. These data suggest that mesangial expansion in recipients with T2DM and obesity may reflect systemic vascular injury and might be a novel biomarker to predict adverse outcomes post renal transplant.  相似文献   
6.
Journal of Digital Imaging - Measurement of angles on foot radiographs is an important step in the&nbsp;evaluation of malalignment. The objective is to develop a CNN model to measure angles on...  相似文献   
7.
Peripheral giant cell granuloma is a lesion arising mainly from the connective tissue of gingiva or periosteum of alveolar ridge. A case of peripheral giant cell granuloma involving a deciduous molar and the succedaneous tooth is reported. The lesion was large and interfered with occlusion. Surgical excision of the lesion along with the deciduous first molar was done. The underlying permanent first premolar was also involved, and had to be removed. The importance of an adequate salivary flow and maintenance of oral hygiene in the prevention of such lesions is stressed.  相似文献   
8.
Purpose: Multiple myeloma is an insidious haematological malignancy characterised by monoclonal proliferation of plasma cells in the bone marrow. Extramedullary plasmacytoma is a rare manifestation of multiple myeloma and usually occurs in the upper respiratory tract. Orbital involvement is particularly uncommon, but may be associated with devastating visual impairment and poor clinical outcomes. Therefore, this article aims to highlight the need for multidisciplinary management of orbital extramedullary plasmacytoma.

Methods: This is a retrospective observational case series of five patients. All presented to the authors for management of orbital extramedullary plasmacytomas from 2004 to 2015 at Prince of Wales and Mater Hospitals in Sydney, Australia. Medical records were reviewed for pertinent information including demographics, disease features, management strategy, and clinical progress. The study met Medical Ethics Board standards and is in accordance with the Helsinki Agreements.

Results: This case series of five patients underscores the poor prognosis of orbital extramedullary plasmacytoma. Despite aggressive multidisciplinary management, four of these five patients succumbed to their illness during the study period. However, multidisciplinary management did manage to minimise symptoms and preserve quality of life.

Conclusions: On a case-by-case basis, patients may derive palliative benefit from orbital surgery in conjunction with radiotherapy and chemotherapy. Orbital surgeons are encouraged to work within a multidisciplinary framework of medical specialists, including haematologists and radiation oncologists, when determining the optimal management plan in cases of orbital extramedullary plasmacytoma.  相似文献   

9.
Congenital renal parenchymal and pelvicalyceal abnormalities have a wide spectrum. Most of them are asymptomatic, like that of ectopia, cross fused kidney, horseshoe kidney, etc., while a few of them become complicated, leading to renal failure and death. It is very important for the radiologist to identify these anatomic variants and guide the clinicians for surgical and therapeutic procedures. Cross-sectional imaging with a volume rendered technique/maximum intensity projection has overcome ultrasonography and IVU for identification and interpretation of some of these variants.  相似文献   
10.
Several studies conducted on chicken have shown that a single stress exposure may impair or improve memory as well as learning processes. However, to date, stress effects on neuronal morphology are poorly investigated wherefore it was of interest to evaluate this further in chicks. Thus, the present study aims to investigate the role of single acute stress (AS) of 24 h food and water deprivation in neuronal plasticity in terms of spine density of the corticoid complex (CC) in 15-day-old chick, Gallus domesticus, by using three neurohistological techniques: Cresyl Violet, Golgi Colonnier, and Golgi Cox technique. The dorsolateral surface of the cerebral hemisphere is occupied by CC which can be differentiated into two subfields: an intermediate corticoid (CI) subfield (arranged in layers) and a dorsolateral corticoid (CDL) subfield. Based on different criteria such as soma shape, dendritic branching pattern, and dendritic spine density, two main moderately spinous groups of neuronal cells were observed in the CC, namely, projection neurons (comprising of multipolar and pyramidal neurons) and stellate neurons. In the present study, the stellate neurons have shown a significant decrease as well as an increase in their spine density in both CI and CDL subfields, whereas the multipolar neurons had shown a significant increase in their spine density in the CDL region only. The present study shows that AS induces neuronal plasticity in terms of spine density in both CI and CDL neurons. The morphological changes in the form of decreased dendritic branches due to stress have been observed in the CI region in comparison to CDL region, which could be linked to more effect of stress in this region. The avian CDL corresponds to the entorhinal cortex of mammals on the basis of neuronal morphology and bidirectional connections between adjacent areas. The projection neurons increase their branches and also their spine number to cope with the stress effects, while the stellate neurons show contrasting effect in their spine density. Therefore, this study will establish that slight modifications in natural stimuli or environmental changes faced by the animal may affect their dorsolateral forebrain which shows neuronal plasticity that help in the development of an adaptive capacity of the animal to survive under changing environmental conditions.  相似文献   
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