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891.
Mirizzi syndrome: noteworthy aspects of a retrospective study in one centre   总被引:14,自引:0,他引:14  
BACKGROUND: Mirizzi syndrome is uncommon. It is, however, clinically important, as it is associated with an increased incidence of bile duct injury and demands more complex surgical techniques. METHODS: A retrospective review of 24 consecutive cases of Mirizzi syndrome that arose between January 1997 and July 2002 was performed. A total of 1881 cholecystectomies were performed during that period. RESULTS: Of the 24 patients, 19 (79.2%) had Mirizzi type I, four (16.7%) had type II, while one (4.2%) had type III disease. Only 54.2% of patients were symptomatic prior to presentation. One-third of patients had normal liver function tests. Ultrasonography and computed tomography were not helpful in diagnosing this entity. Endoscopic retrograde cholangiopancreatography (ERCP) was useful to identify cholecystocholedochal fistulas and to allow therapeutic endoscopic stenting but failed to pick up the syndrome in half of the patients. Inadvertent bile duct injury occurred in four patients (16.7%), all occurred in patients without a preoperative diagnosis. Three of the four injuries occurred during operations by a senior registrar rather than a consultant. Mirizzi type I was managed with either total or subtotal cholecystectomy, while types II and III cases were managed with either T-tube insertion or biliary bypass procedures. Bile duct injury was managed with T-tube successfully in one patient while the rest went on to biliary bypass operations. All except one patient had good functional outcomes on follow up. CONCLUSION: The preoperative diagnosis of Mirizzi syndrome is a challenge. Only constant vigilance during intraoperative dissection of the Calot's triangle will reduce the incidence of bile duct injury in Mirizzi syndrome that can occur in both open and laparoscopic surgery.  相似文献   
892.
The purpose of the present research was to examine younger (7-years-old) and older (10-years-old) children's attitudes toward older individuals following one type of five primes: positive prime, negative prime, elderly prime, grandparent prime, or neutral prime. Overall, children's attitudes on three tests--Apperception, Semantic Differential, and Attribute Salience--were affected by the type of prime children were given, with positive and grandparent primes resulting in more positive views toward older individuals than negative, elderly, or neutral (control group) primes. The present research provides evidence that priming the most accessible cognitions about an individual can affect even young children's perception of the individual. These results are discussed in terms of category-based and data-driven processing and may explain the disparate findings obtained in previous studies that have shown the children's attitudes toward older individuals are sometimes negative, whereas other studies have shown that children's attitudes are more positive or neutral.  相似文献   
893.
Double high-dose chemotherapy (HDCT) was applied to 18 patients with highrisk neuroblastoma including 14 patients who could not achieve complete response (CR) even after the first HDCT. In 12 patients, successive double HDCT was rescued with peripheral blood stem cells collected during a single round of leukaphereses and in 6 patients, second or more rounds of leukaphereses were necessary after the first HDCT to rescue the second HDCT. The median interval between the first and second HDCT (76 days; range, 47-112) in the single harvest group was shorter than that (274.5 days; range, 83-329) in the double harvest group (p<0.01). Hematologic recovery was slow in the second HDCT. Six (33.3%) treatment-related mortalities (TRM) occurred during the second HDCT but were not related to the shorter interval. Disease-free survival rates at 2 years with a median follow-up of 24 months (range, 6-46) in the single and double harvest group were 57.1% and 33.3%, respectively. These results suggest that successive double HDCT using the single harvest approach may improve the survival of high-risk patients, especially who could not achieve CR after the first HDCT despite delayed hematologic recovery and high rate of TRM during the second HDCT.  相似文献   
894.
This study investigated a laboratory-based driving simulator and identified assessment criteria for its use as an off-road screening tool for older adult drivers. The driving performance of 53 volunteer older adults was assessed by the driving simulator and gauged by age-specific assessment criteria. The assessment criteria used in this study were cognitive functions required in making decisions based on past driving experience and ever-changing driving conditions. The Cronbach alpha confirmed internal consistency of the scales that comprised the measures of driving performance. Pearson coefficient showed some assessment criteria were significantly correlated with age of participants (−0.59  <   r  <  0.49). The multivariate analysis of variance revealed that there was an overall score difference in driving performance between two age groupings: senior drivers and advanced age senior drivers. The younger the age of the participants, the better they performed in driving as defined by the assessment criteria. The findings of this study do not deviate from the literature supporting the evidence that driving ability declines with age. It was established that if appropriate assessment criteria are chosen, driving simulators can differentiate between levels of older adults' driving skills.  相似文献   
895.
Programmed cell death (PCD) is a prominent feature of the development of the immune and nervous systems. In both systems, widespread PCD occurs in primitive progenitor cells during development. In this study, we demonstrated that Ewing’s sarcoma (ES) cells, undifferentiated neural precursors, underwent apoptosis upon engagement of CD99 with anti-CD99 monoclonal antibody. Apoptosis via CD99 occurred only in the undifferentiated state of ES cells, but not in differentiated ES cells. CD99-induced apoptosis in ES cells appeared to require de novo synthesis of RNA and protein as well as caspase activation. Cyclosporin A, known to be a potent inhibitor of both calcineurin activation and mitochondrial permeability transition pore opening, inhibited CD99-mediated apoptosis, whereas FK-506, a specific calcineurin inhibitor, did not, indicating the induction of CD99-mediated apoptosis through a calcineurin-independent pathway. Furthermore, the dying cells displayed the reduction of mitochondrial transmembrane potential (ΔΨm). These results suggest that CD99 engagement induce CsA-inhibitable mitochondrial permeability transition pore opening, followed by a reduction of ΔΨm and caspase activation, thereby leading to apoptosis. Based on these results, we suggest the possible involvement of CD99 in the apoptotic processes that occur during nervous system development and also its application in immunotherapeutic trials for ES cases.  相似文献   
896.
A rare case of symmetric renal extramedullary hematopoiesis is hypothesized in a patient with longstanding Vaquez' disease and myelofibrosis. At CT, soft tissue densities were found in the renal hilar area encasing the pelvicalyceal system. Although there is nothing specific about the CT findings, the diagnosis can be suggested in the proper clinical setting. The association with generalized osteosclerosis is another diagnostic clue.  相似文献   
897.
Axial CT scans of 60 patients with biopsy-proved nasopharyngeal carcinoma were reviewed with particular reference to sites of origin and routes of spread of disease. In all patients there was involvement of the pharyngeal space with blunting of the fossa of Rosenmuller and usually associated thickening of the adjacent levator veli palatini muscle. Tumor infiltration through the pharyngobasilar fascia manifested by obliteration or displacement of the parapharyngeal fat space was seen in 65% of the patients. T-staging by CT showed T1 (28%), T2 (20%), T3 (5%), and T4 (47%) involvement. In three patients there was bilateral symmetric blunting of the fossa of Rosenmuller with no evidence of tumor infiltration into the parapharyngeal space. The scans were initially interpreted as normal except for widening of the preoccipital soft-tissue area in the midline of more than 1.5 cm and up to 2.0 cm in the anteroposterior plane. Biopsy of the postnasal space was positive for tumor in these patients. With symmetric, early stage nasopharyngeal carcinoma, a confident radiologic diagnosis on CT can be difficult. If there is asymmetry of pharyngeal mucosal space or evidence of deep infiltration this should not be a problem. Although lymphoid adenoid tissue can sometimes result in widening of the preoccipital area, it is proposed that widening of this area of greater than 1.5 cm is an additional CT sign of nasopharyngeal carcinoma not previously emphasized. It is the result of early submucosal infiltration of the disease, and a patient with clinically suspected nasopharyngeal carcinoma should have aggressive deep biopsies of the fossa of Rosenmuller.  相似文献   
898.
K W Sharif  T A Casey  R Casey  W K Hoe 《Cornea》1992,11(2):155-162
A 76-year-old man with bilateral practolol-induced dry eyes developed atypical acute bilateral corneal calcification. Serum calcium, phosphate, and urea levels were within normal limits. The calcium deposition progressed rapidly to involve 90% of the right cornea. Right penetrating keratoplasty was performed with subsequent visual rehabilitation of the patient. Left tectonic penetrating keratoplasty was performed 8 weeks later after corneal perforation. The corneal specimens were examined by light and electron microscopy, which showed an atypical calcareous degeneration involving Bowman's layer as well as the full thickness of the stroma. Transmission electron microscopy showed the granular calcification to consist of extracellular, radially orientated aggregates of fine, needle-shaped crystals. Both transplants remained clear with no evidence of postoperative recurrence. To our knowledge this is the first report of bilateral penetrating keratoplasty for acute calcareous degeneration.  相似文献   
899.
900.
Spiral CT and magnetic resonance angiography (MRA) were performed in ten patients with 14 intracranial aneurysms known from conventional angiography. All lesions, the smallest 3 mm in diameter, were visible on spiral CT and MRA. The neck of the aneurysm and its anatomical relations could very accurately be determined in all cases. Advantages of spiral CT over MRA are: a short acquisition time with reduction of motion artefacts, no dependence on flow rate or cardiac output, and excellent visualisation of calcification, thrombus and bony landmarks. Disadvantages are the necessity for iodinated contrast medium, long postprocessing and reconstruction time and the possibility of overlap of bone and venous blood.  相似文献   
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