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81.

Background

Obstructive jaundice is frequently associated with false CA19-9 elevation in benign conditions. The diagnostic accuracy of this tumor marker was evaluated in the present longitudinal study.

Methods

In 128 patients admitted for obstructive jaundice (87 with pancreato-biliary malignancy and 41 benign disease) serum CA19-9 was measured. Statistical analysis of marker levels obtained before and after endoscopic biliary drainage was performed in 60 patients.

Results

Elevated CA19-9 levels (>37 U/mL) were found in 61% of benign cases and 86% of malignancies. After biliary drainage, decrease of serum CA19-9 was observed in 19 of 38 malignant cases and in almost all benign cases (Wilcoxon matched pairs test: P = .207 and P <.001, respectively). Receiver operating characteristic (ROC) analysis identified a cut-off value of 90 U/mL to be associated with improved diagnostic accuracy after biliary drainage (sensitivity 61%, specificity 95%).

Conclusions

In the presence of successfully drained obstructive jaundice, CA19-9 serum levels that remain unchanged or measure more than 90 U/mL are strongly indicative of a malignant cause of obstruction. However, the real clinical utility of this marker remains controversial.  相似文献   
82.
We previously showed cell–cell contacts of human dermal fibroblasts to induce expression of the hepatocyte growth factor/scatter factor (HGF) in a process designated as nemosis. Now we report on nemosis initiation in bone marrow mesenchymal stem cells (BMSCs). Because BMSCs are being used increasingly in cell transplantation therapy we aimed to demonstrate a functional effect and benefit of BMSC nemosis for wound healing. Nemotic and monolayer cells were used to stimulate HaCaT keratinocyte migration in a scratch-wound healing assay. Both indicators of nemosis, HGF production and cyclooxygenase-2 expression, were induced in BMSC spheroids. When compared with a similar amount of cells as monolayer, nemotic cells induced keratinocyte in vitro scratch-wound healing in a concentration-dependent manner. The HGF receptor, c-Met, was rapidly phosphorylated in the nemosis-stimulated keratinocytes. Nemosis-induced in vitro scratch-wound healing was inhibited by an HGF-neutralizing antibody as well as the small molecule c-Met inhibitor, SU11274. HGF-induced in vitro scratch-wound healing was inhibited by PI3K inhibitors, wortmannin and LY294002, while LY303511, an inactive structural analogue of LY294002, had no effect. Inhibitors of the mitogen-activated protein kinases MEK/ERK1/2 (PD98059 and U0126), and p38 (SB203580) attenuated HGF-induced keratinocyte in vitro scratch-wound healing. We conclude that nemosis of BMSCs can induce keratinocyte in vitro scratch-wound healing, and that in this effect signaling via HGF/c-Met is involved.  相似文献   
83.

Purpose

Hepatectomy remains a complex operation even in experienced hands. The objective of the present study was to describe our experience in liver resections, in the light of liver transplantation, emphasizing the indications for surgery, surgical techniques, complications, and results.

Methods

The medical records of 53 children who underwent liver resection for primary or metastatic hepatic tumors were reviewed. Ultrasonography, computed tomographic (CT) scan, and needle biopsy were the initial methods used to diagnose malignant tumors. After neoadjuvant chemotherapy, tumor resectability was evaluated by another CT scan. Surgery was performed by surgeons competent in liver transplantation. As in liver living donor operation, vascular anomalies were investigated. The main arterial anomalies found were the right hepatic artery emerging from the superior mesenteric artery and left hepatic artery from left gastric artery. Hilar structures were dissected very close to liver parenchyma. The hepatic artery and portal vein were dissected and ligated near their entrance to the liver parenchyma to avoid damaging the hilar vessels of the other lobe. During dissection of the suprahepatic veins, the venous infusion was decreased to reduce central venous pressure and potential bleeding from hepatic veins and the vena cava.

Results

Fifty-three children with hepatic tumors underwent surgical treatment, 47 patients underwent liver resections, and in 6 cases, liver transplantation was performed because the tumor was considered unresectable. There were 31 cases of hepatoblastoma, with a 9.6% mortality rate. Ten children presented with other malignant tumors—3 undifferentiated sarcomas, 2 hepatocellular carcinomas, 2 fibrolamellar hepatocellular carcinomas, a rhabdomyosarcoma, an immature ovarian teratoma, and a single neuroblastoma. These cases had a 50% mortality rate. Six children had benign tumors—4 mesenchymal hamartoma, 1 focal nodular hyperplasia, and a mucinous cystadenoma. All of these children had a favorable outcome. Hepatic resections included 22 right lobectomies, 9 right trisegmentectomies, 8 left lobectomies, 5 left trisegmentectomies, 2 left segmentectomies, and 1 case of monosegment (segment IV) resection. The overall mortality rate was 14.9%, and all deaths were related to recurrence of malignant disease. The mortality rate of hepatoblastoma patients was less than other malignant tumors (P = .04).

Conclusion

The resection of hepatic tumors in children requires expertise in pediatric surgical practice, and many lessons learned from liver transplantation can be applied to hepatectomies. The present series showed no mortality directly related to the surgery and a low complication rate.  相似文献   
84.
INTRODUCTION: The most frequent cause of pneumoperitoneum is gastroduodenal ulcer. Perforations of the small bowel are uncommon compared with perforations of the rest of the alimentary tract and radiological findings of jejunoileal perforation have not been frequently reported. The aim of our retrospective study was to assess the CT findings in 18 patients with jejunoileal perforation. MATERIAL AND METHODS: We retrospectively reviewed the CT findings in 18 patients (12 men and 6 women, age ranging 14 to 84 years, mean age 42 years) operated for jejunoileal perforation at Cardarelli Hospital, Naples. CT examination was performed in all patients after i.v. injection of contrast medium and in two cases after oral contrast medium administration. Free intraperitoneal air, extravasation of ingested contrast media and visualization of a discontinuity in the bowel wall were considered direct findings of jejunoileal perforation, while intraperitoneal free fluid, thickened bowel wall and the presence of a streaky density within the mesentery were considered indirect diagnostic findings. RESULTS: The site of perforation was the jejunum in 6 cases and the ileum in 12 cases. The following CT findings were retrospectively observed: intraperitoneal free fluid (61%), free intraperitoneal air (33%), thickened bowel wall (22.2%), presence of a streaky density within the mesentery (5.5%). Visualization of a discontinuity in the bowel wall and extravasation of ingested contrast media were never seen. We observed two findings of perforation in 7 cases, and a single finding in 8 cases. CT examination was negative in 3 cases. CONCLUSIONS: Jejunoileal perforations are difficult to identify by CT. In our series, free intraperitoneal air, as a direct finding of perforation, was observed in 33% of cases, while free intraperitoneal fluid, as an indirect diagnostic finding, was the most frequent sign.  相似文献   
85.
Radical endoscopic assisted perineal prostatectomy   总被引:2,自引:0,他引:2  
PURPOSE: During radical perineal prostatectomy transection of the bladder neck and dissection of the seminal vesicles under direct vision can be difficult. We describe a technique of radical endoscopic assisted perineal prostatectomy that facilitates dissection of these structures. MATERIALS AND METHODS: Cadaveric dissections were performed in 4 individuals to develop and assess the technique. It was subsequently applied to a 64-year-old male with clinically localized prostate cancer (Gleason grade 3+3). Management of the bladder neck and seminal vesicles was performed with a bipolar transurethral resectoscope. The remainder of the procedure was performed via a traditional subsphincteric perineal approach with the patient in the standard dorsal lithotomy position. RESULTS: The bladder neck and seminal vesicles were successfully dissected in 55 minutes. Total operative time was 3 hours. Estimated blood loss was 500 cc. The patient was discharged home the morning of postoperative day 1 and the catheter was removed in the clinic on postoperative day 7. The final pathology report showed organ confined prostate cancer (Gleason 3+3). CONCLUSIONS: Radical endoscopic assisted perineal prostatectomy allows precise dissection of the bladder neck and seminal vesicles under direct vision. Accomplishing this dissection as the initial step of the procedure mobilizes the prostate, facilitating excision, and obviates the need for the extreme lithotomy position.  相似文献   
86.
Degeneration of the disc or discs between two fused spinal segments has been termed "floating disc disease". The purpose of this retrospective study was to show the radiological evolution of the floating disc(s) and the relationship between floating disc degeneration and segmental lordosis, lumbar lordosis and pelvic incidence. Twenty patients, with a mean age of 49.9 years, with symptomatic lumbar degenerative disc disease or low grade spondylolisthesis, who failed non-operative treatment and underwent fusion of 2 or more noncontiguous spinal segments, were included in this study. The radiographs of the floating discs were graded with the modified Gore System. The mean follow-up was 4.2 years. Forty-seven levels were fused and 27 floating discs were studied (13 single, 7 double). Five out of 27 floating discs (18%), in 4 patients, progressively degenerated. None of the floating discs degenerated more than two radiographic grades and none needed additional surgery. Postoperatively, 3 out of 5 degenerated floating discs had decreased segmental lordosis, while the other two had no change; this difference was not significant (p = 0.08). Neither was there any significant correlation between floating disc degeneration and lumbar lordosis L1-S1 (p > 0.10) or pelvic incidence (p > 0.10). This study shows that the effect of floating fusion on floating discs is the same as the effect of a contiguous fusion on adjacent discs.  相似文献   
87.
88.
89.
An exceptional case of tracheal agenesis with no communication with the esophagus is described. This malformation needs surgical airway approach and is hardly classifiable. We analyzed the literature and our institutional data: this resulted to be the first case of such anatomical variant. Genetic and pathological issues are reviewed: recent genetic data seem to explain this malformation. We also reviewed the available literature about prenatal presentation. Because prenatal diagnosis is difficult to achieve and current guidelines for neonatal resuscitation do not provide any recommendation, the resuscitative team may not be prepared for managing such a case. Usefulness of uncommon resuscitative maneuvers is discussed: a promptly performed surgical tracheotomy is the only mean to ventilate such a baby.  相似文献   
90.
The Nd:YAG laser efficacy associated with conventional treatment for bacterial reduction has been investigated throughout literature. The purpose of this study was to evaluate the bacterial reduction after Nd:YAG laser irradiation associated with scaling and root planning in class II furcation defects in patients with chronic periodontitis. Thirty-four furcation lesions were selected from 17 subjects. The control group received conventional treatment, and the experimental group received the same treatment followed by Nd:YAG laser irradiation (100 mJ/pulse; 15 Hz; 1.5 W, 60 s, 141.5 J/cm2). Both treatments resulted in improvements of most clinical parameters. A significant reduction of colony forming unit (CFU) of total bacteria number was observed in both groups. The highest reduction was noted in the experimental group immediately after the treatment. The number of dark pigmented bacteria and the percentage of patients with Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans reduced immediately after the treatment and returned to values close to the initial ones 6 weeks after the baseline for both groups. The Nd:YAG laser associated with conventional treatment promoted significant bacterial reduction in class II furcation immediately after irradiation, although this reduction was not observed 6 weeks after the baseline.  相似文献   
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