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41.
本文用 BALB/3T3 A31-1-13细胞系研究了煤尘抽提物的转化活性。亚硝化和未亚硝化的煤尘抽提物都能诱发细胞发生转化且有剂量反应关系.但亚硝化煤尘抽提物的转化活性比未亚硝化者高。从转化集落分离出来的细胞具有赘生转化的一些特征,如细胞生长迅速、接触抑制消失和停泊不依赖性生长等.本文结果看来支持煤矿工胃癌高发原因的煤尘假说。  相似文献   
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Bacterial meningitis in infants: sonographic findings   总被引:1,自引:0,他引:1  
Han  BK; Babcock  DS; McAdams  L 《Radiology》1985,154(3):645-650
A retrospective study was performed on 78 patients (newborn to 2 years old) with clinically proved bacterial meningitis. Sonograms were obtained during the acute illness and medical records were reviewed. The spectrum of sonographic features of meningitis included normal scans (30 patients), ventriculomegaly (11 patients), echogenic sulci (31 patients), extra-axial fluid collections (26 patients), abnormal parenchymal echogenicity (9 patients), evidence of ventriculitis (5 patients), and brain abscess (1 patient). In 46 patients, correlation between the sonographic findings and neurologic outcome on clinical follow-up (6 months to 4 years) was made. Findings of abnormal parenchymal echogenicity and/or moderate-to-marked ventriculomegaly were associated with significant neurologic sequelae; however, echogenic sulci and small extra-axial fluid collections did not appear to have any prognostic significance. Twenty-nine of the 78 patients had sonography without clinical indication of complications of meningitis, and in no patient was a significant abnormality found. Our study suggests that sonography is indicated only when there is clinical suspicion of complications.  相似文献   
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Introduction

Biliary atresia (BA) is a rare, potentially life-threatening condition of the newborn presenting with conjugated jaundice. Typically, it is treated by an initial attempt to restore bile flow (the Kasai portoenterostomy [KP]) as soon as possible after diagnosis and, if this fails, liver transplantation. Since 1999, the treatment of BA has been centralized to 3 centers in England and Wales able to offer both treatment options. The aim of this study was to review the outcome of this policy change and provide a national benchmark.

Methods

The management of all infants born within England and Wales during the period January 1999 to December 2009 was assessed using 3 key performance indicators such as median time to KP, percentage clearance of jaundice (≤20 mol/L) post-KP, and 5- and 10-year native liver and true survival estimates. Data are quoted as median (range), and P < .05 was considered significant.

Results

A total of 443 infants had confirmed BA; and of these, most were isolated BA (n = 359), with 84 having other significant anomalies (but predominantly BA splenic malformation syndrome). Four infants died before any biliary intervention. Kasai portoenterostomy was performed in 424 infants (median age, 54 [range 7-209] days), and a primary liver transplant was performed in 15. Clearance of jaundice post-KP was achieved in 232 (55%). There were 41 deaths, including 4 (10%) without any intervention, 24 (58%) post-KP usually because of end-stage liver disease and mostly on a transplant waiting list, and 13 (32%) post-LT usually because of multiorgan failure. Overall, the 5- and 10-year native liver survival estimates were 46% (95% confidence interval [CI], 41-51) and 40% (95% CI, 34-46), respectively. The 5- and 10-year true patient survival estimates were 90% (95% CI, 88-93) and 89% (95% CI, 86-93), respectively. Outcome was worse for those with other anomalies (lower clearance of jaundice post-KP [43% vs 57%; odds ratio, 1.7; 95% CI, 1.04-2.8]; P = .02) and an increased mortality overall (eg, at 5 years, 72 [95% CI, 64-83] vs 94 [95% CI, 91-96]; χ2 = 33; P < .0001).

Conclusions

National outcome measures in BA appear better than those from previously published series from comparable countries and may be attributed to centralization of surgical and medical resources.  相似文献   
48.
Malignant peripheral nerve sheath tumor is a rare neurogenic tumor that usually presents in geriatic patients. Typically, it is found in the trunk and extremities and rarely presents in the head and neck region. It may mimic a carotid body tumor when it presents in the neck. We report the first case of malignant peripheral nerve sheath tumor of the vagus nerve in an adolescent boy. He presented with an asymptomatic lateral neck lump that was thought to be a benign schwannoma on preoperative imaging. We describe the diagnostic dilemma and management difficulties in this patient and review the literature.  相似文献   
49.
Synovial chondromatosis is an uncommon disorder with rare occurrence in the elbow. Case reports in the literature for elbow synovial chondromatosis have described presenting symptoms secondary to peripheral nerve compressions or localized bursitis. We discuss a case of synovial chondromatosis of the elbow that presented as an isolated soft-tissue mass over the radial head-more suggestive of a soft-tissue tumor than of synovial chondromatosis.  相似文献   
50.
We evaluated the safety and efficacy of a 72-h epidural infusion of ropivacaine and measured the impact of adding fentanyl 2 microg/mL to the required infusion rate, on the quality of postoperative pain relief and the incidence of side effects, after colonic surgery. One hundred fifty-five patients scheduled for elective colonic surgery were randomized in this trial. Epidural infusions of ropivacaine 2 mg/mL with fentanyl 2 microg/mL (R + F) and without fentanyl (R) were commenced during surgery and continued for 72 h postoperatively. This was a prospective, randomized, double-blinded, multi-center trial. The median infusion rate required was less in the R + F group (9.3 vs 11.5 mL/h, P < 0.001). Median pain scores at rest and on coughing were lower in the R + F group (P < 0.0001). The incidence of hypotension was more in the R + F group (P = 0.01). Time to readiness for discharge was delayed in the R + F group (median 6.6 vs 5.5 days, P = 0.012). The addition of fentanyl to ropivacaine resulted in decreased infusion rates and enhanced pain control; however, adverse effects were increased and readiness to discharge was delayed. IMPLICATIONS: Epidural infusions of ropivacaine with and without fentanyl were administered to patients to control pain after colonic surgery. Patients who received ropivacaine with fentanyl had better pain control, increased side effects, and delayed readiness to discharge. This study questions the value of adding opioids to epidural infusions of local anesthetics.  相似文献   
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