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11.
Cystic lesions of the thyroid are common findings. Although many thyroid cysts are of benign, some cases of hemorrhagic degenerative changes occur in neoplastic nodules, mostly follicular neoplasms and papillary carcinomas. The occurrence of hemorrhagic changes in medullary carcinomas has never been documented with aspirative cytological and histological pictures to the best of our knowledge. A case of medullary thyroid carcinoma with a large central hemorrhagic cyst is described, and the literature regarding the pathogenesis of this regression and the occurrence of cystic neoplasms in the thyroid is reviewed.  相似文献   
12.
This study was carried out to evaluate the rate of recovery and time required for detection of mycobacteria from pulmonary and extrapulmonary human clinical samples, by using a fluorescence-quenching-based oxygen sensor (BACTEC 9000 MB; Becton Dickinson Microbiology Systems, Sparks, Md.). The results were compared with those obtained by microscopy, conventional culture in Lowenstein-Jensen (LJ) medium, and a BACTEC radiometric system (BACTEC 460 TB; Becton Dickinson). Of the 779 clinical samples processed, 364 from pulmonary sites and 415 from extrapulmonary sites, 62 (7.9%) were positive for mycobacterial isolates; of the positive samples, 59 (95.1%) were detected with the fluorescent BACTEC 9000 MB system, 57 (91.9%) were detected with the radiometric system (BACTEC 460 TB), and 43 (69.3%) were detected with LJ conventional culture. The mean times to detection of all mycobacteria with BACTEC 9000 MB and BACTEC 460 TB were similar (10.3 and 10.0 days, respectively). The results obtained indicate that the nonradiometric BACTEC (BACTEC 9000 MB) system is as efficient as Bactec 460 TB and significantly more efficient than LJ for the rapid recovery of mycobacteria from both pulmonary and extrapulmonary clinical specimens. Though the BACTEC 9000 MB system is recommended for respiratory specimens, we demonstrated that it can be successfully used also for recovery of mycobacteria from clinical specimens from various extrapulmonary sites.  相似文献   
13.
Sixty-five mass lesions of parotid origin were evaluated using thin-section high-resolution computed tomography to ascertain histologic specificity. All patients were studied after infusion of intravenous contrast media. Factors judged included the extent of glandular involvement, invasion of adjacent soft tissues, degree of postcontrast computed tomography density (relative to muscle), and the presence of calcification.  相似文献   
14.

Background

The efficacy and safety of self-expandable metallic stent (SEMS) placement as a bridge to elective surgery or definitive palliation versus emergency operation to treat colorectal obstruction is debated. This study aimed to evaluate the outcomes of patients with colorectal obstruction treated using different strategies.

Methods

Subjects admitted to the authors’ department with colorectal obstruction (n = 134) were studied prospectively. They underwent endoscopic stenting as a bridge to elective surgery (SEMS group: n = 49) or for definitive palliation (n = 34). A total of 51 patients underwent immediate surgery without stenting (NO-SEMS). Treatment was decided by the senior on-call surgeon.

Results

Placement of SEMS was technically successful in 95.3 % and clinically successful in 98.7 % of cases. The short-term complications in the SEMS group were perforation (n = 1, 1.2 %), migration (n = 4, 4.9 %), occlusion (n = 4, 4.9 %), colon bleeding (n = 3, 3.7 %), and abdominal pain (n = 6, 7.4 %). The postoperative complication rate was 32.7 % in the SEMS group versus 60.8 % in the NO-SEMS group (P = 0.005), with a significant reduction in wound infections (26.5 vs 54.9 %; P = 0.004), abdominal abscess (14.3 vs 39.2 %; P = 0.006), respiratory morbidity (10.2 vs 37.3 %; P = 0.002), and intensive care treatment (10.2 vs 33.3 %; P = 0.007). The median postoperative hospital stay was 10 versus 15 days (P = 0.001). The in-hospital mortality rate in both groups was 2 %. Long-term follow-up evaluation showed less incisional hernia (6.3 vs 22.0 %; P = 0.04) and definitive stoma formation (6.3 vs 26.0 %; P = 0.01) in the SEMS group than in the NO-SEMS group, respectively. Kaplan–Meier survival curves showed a benefit for the SEMS group (log-rank test, 0.004). The long-term SEMS-related complication rate for the palliative patients was 43.8 %. The hospital readmission rate for SEMS complications was 34.4 %. Overall clinical success was 81.2 %.

Conclusions

In case of colorectal obstruction, endoscopic colon stenting as a bridge to elective operation should be considered as the treatment of choice for resectable patients given the significant advantages for short- and long-term outcomes. Palliative stenting is effective but associated with a high rate of long-term complications.  相似文献   
15.

Introduction

The Y-box binding protein-1 (YB-1) is a multifunctional oncoprotein involved in the proliferation and aggressiveness of cancer cells. The aim of this study was to determine whether strong YB-1 expression in neoplastic cells of colorectal liver metastases (CRLM) may have an impact on liver disease-free survival following liver resection.

Materials and Methods

Immunohistochemistry was performed to evaluate YB-1 in 66 patients who underwent liver resection for CRLM. YB-1 expression was classified as weak (low-staining intensity) and strong (high-staining intensity).

Results

YB-1 expression was observed in the cytoplasm of all CRLM. YB-1 expression was weak in 17 patients (25.8 %) and strong in 49 patients (74.2 %). Liver recurrence rate was significantly higher in the strong than in the weak expression group: 55.1 vs. 23.5 % (p?=?0.023). Multivariable logistic regression analysis showed that YB-1 strong expression was the only independent risk factor for liver recurrence. The 5-year specific liver disease-free survival rate was 76.0 % in the weak expression group and 41.5 % in the strong expression group (p?=?0.034). These results were not influenced by clinical prognostic factors of tumor recurrence.

Conclusions

This is the first study showing that the degree of YB-1 expression in tissue specimens of CRLM predicts liver recurrence following liver resection.  相似文献   
16.
A large Italian pedigree from southern Italy with autosomal dominant uncomplicated spastic paraplegia is reported. The clinical picture was uniform and characterized by insidiously progressive lower extremity weakness and spasticity. The mean age at onset of symptoms was 8.3 years. Significant linkage to the SPG3 locus on chromosome 14 was detected. The authors also report their search for mutations in a gene located in the region and its exclusion as a candidate for SPG3. Received: 14 November 2001, Received in revised form: 8 April 2002, Accepted: 23 April 2002 Correspondence to A. Quattrone, MD  相似文献   
17.
Methyl-tertiary-butyl ether (MTBE) is a ubiquitous oxygen-bearing additive used to reduce engine knocking and obtain cleaner gasoline combustion. Conflicting data have been reported about a possible carcinogenic role of MTBE in humans. In this study we evaluated the effects of MTBE on cell growth and transformation in rodent fibroblasts. We found that MTBE inhibits cell proliferation in a dose- and time-dependent pattern with an IC50 of about 0.84 mM. We also studied the effects of MTBE on cell cycle distribution. The most striking effect was a reduction in the percentage of cells in the G2/M-phase which was associated with an increase of cells in the S-phase of the cell cycle, as assessed by flow cytometry. At a dose corresponding to IC50, a subdiploid peak indicative of apoptosis, was also evident. MTBE was also able to induce cell transformation in vitro. In conclusion, our results suggest that MTBE can affect cell growth and induce cell transformation in cultured rodent fibroblasts.  相似文献   
18.
HYPOTHESIS: Bile duct injury (BDI) remains the most serious complication of cholecystectomy. With laparoscopic cholecystectomy (LC), the incidence has become more frequent. This study verifies the current incidence, mechanism, presentation, and treatment of BDI occurring during LC in general surgical practice. DESIGN: Anonymous retrospective multicenter survey. SETTING: Department of surgery at a university referral center, collecting data from general surgical units. PATIENTS: Data from 56 591 patients who underwent LC between January 1, 1998, and December 31, 2000, in 184 hospitals in Italy were analyzed. MAIN OUTCOME MEASURES: Current incidence, mechanism, presentation, and treatment of BDI occurring during LC in general surgical practice. RESULTS: Two hundred thirty-five BDIs were reported, with an overall incidence of 0.42%. There were no risk factors in 80.0% of the patients. Poor identification of the anatomical features of the hepatic pedicle was the most frequently reported cause (36.8%), and technical problems accounted for 27.0% of causes. The incidence of BDI was higher during cholecystitis (P<.001) and decreased with increasing number of LCs performed by the surgical teams (P<.01). There was no difference in incidence according to technique (French or US) or to routine or selective intraoperative cholangiography. One hundred eight BDIs (46.0%) were recognized intraoperatively and immediately repaired in 89.8% of patients. One hundred twenty-seven BDIs (54.0%) were diagnosed postoperatively, the dominant manifestation being biliary fistula (44.1%). CONCLUSIONS: This study confirms a higher incidence of BDI during LC. It highlights the relevance of the number of previously performed LCs and of the correct surgical technique to avoid BDI. The need for correct procedures, adequate expertise of the repairing surgeon in BDI repairs, and a multidisciplinary approach in the management of BDI is emphasized.  相似文献   
19.
In order to investigate new therapeutic strategies for hepatocellular carcinoma (HCC), an animal model easily reproducible of hepatic tumor is necessary. Several techniques of intrahepatic tumor implantation have been reported in the literature. Many of them have the disadvantage of high rate of artificial neoplastic extrahepatic dissemination, both peritoneal and systemic. These drawbacks interfere with the evaluation of treatment efficacy. In this study we describe a modified technique of intrahepatic tumor implantation in the rat, previously reported by Yang in 1992, which is based on the insertion in the liver, after neoplastic tissue, of a piece of hemostatic sponge (Spongostan) that permits to significantly reduce the rate of artificial neoplastic dissemination. Nine ACI/T rats were used and Morris hepatoma 3924A was implanted in the right hepatic lobe. In all cases an intrahepatic tumor take was documented by MRI and by histological examination. No lung metastases were observed. In only one animal peritoneal and subcutaneous nodules were seen, likely due to a technique mistake. According to tumor growth curve it is possible to observe that, with this technique, a 1 cm tumor nodule is obtainable 10 days after the implantation, without extrahepatic metastases, easily detectable by imaging techniques such as MRI used in this study. In conclusion this modified technique of intrahepatic tumor implantation permits to obtain an intrahepatic tumor animal model which is easily reproducible and suitable for the evaluation of efficacy of experimental therapies for HCC.  相似文献   
20.
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