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21.

Background

After a brain biopsy, the genetic analysis can fail because of insufficient material, extensive tumor necrosis, and formalin fixation under conditions that adversely affected the quality of the DNA or because the assay result was indeterminant. The freezing of fresh tumor tissue at surgery could greatly improve the success of DNA extraction and methyl guanine methyl transferase (MGMT) promoter methylation testing. The concentration of the DNA samples can also be improved from a withdrawal in an area with a high probability of neoplastic cells.

Methods

The present study reports the results of ten frameless image-guided intracranial needle biopsies from April 2008 until February 2009, among a total of 28 frameless neuronavigation brain biopsy performed from May 2007 to February 2009. The protocol sampling provided withdrawal specimens correlated with neuroimaging characteristics of the lesions. The molecular determination of MGMT promoter was assessed with the nested methylation-specific polymerase chain reaction on fresh or cryopreserved needle bioptic tissue.

Results

The genetic characterization was feasible in all the bioptic samples. The MGMT promoter was methylated in six patients, including a brain infection. The image-guided trajectory of the biopsy and the intraoperative frozen section increased the diagnostic yield.

Conclusions

To the best of the authors' knowledge, this is the first report with the MGMT promoter status analysis on needle bioptic fresh tissue. In the future, the availability of the molecular genetic characterization of a brain tumor before open surgery will provide important information for the optimal treatment.  相似文献   
22.
Understanding the contributions of the prefrontal cortex (PFC) to working memory is central to understanding the neural bases of high-level cognition. One question that remains controversial is whether the same areas of the dorsolateral PFC (dlPFC) that participate in the manipulation of information in working memory also contribute to its short-term retention (STR). We evaluated this question by first identifying, with functional magnetic resonance imaging (fMRI), brain areas involved in manipulation. Next, these areas were targeted with repetitive transcranial magnetic stimulation (rTMS) while subjects performed tasks requiring only the STR or the STR plus manipulation of information in working memory. fMRI indicated that manipulation-related activity was independent of retention-related activity in both the PFC and superior parietal lobule (SPL). rTMS, however, yielded a different pattern of results. Although rTMS of the dlPFC selectively disrupted manipulation, rTMS of the SPL disrupted manipulation and STR to the same extent. rTMS of the postcentral gyrus (a control region) had no effect on performance. The implications of these results are twofold. In the PFC, they are consistent with the view that this region contributes more importantly to the control of information in working memory than to its STR. In the SPL, they illustrate the importance of supplementing the fundamentally correlational data from neuroimaging with a disruptive method, which affords stronger inference about structure-function relations.  相似文献   
23.

Purpose  

To study the benefits of a single, early, intravesical instillation of mitomycin C(MMC) after transurethral bladder resection (TURB) in patients with low-risk non-muscle-invasive bladder cancer (NMIBC).  相似文献   
24.
Abstract:  Mycophenolate mofetil (MMF) and sirolimus (SRL) are effective immunosuppressive drugs with distinct safety profile.
Methods:  Kidney transplant recipients receiving tacrolimus (TAC)-based immunosuppressive regimen were randomized to receive fixed daily doses of MMF (2 g/d, n = 50) or SRL (one loading dose of 15 mg, 5 mg/d till day 7 and 2 mg/d thereafter, n = 50) without induction therapy.
Results:  No differences were observed in the incidence of the composite (biopsy-confirmed acute rejection, graft loss or death) end-point (18% vs. 16%, p = 1.000), biopsy confirmed acute rejection (12% vs. 14%, p = 1.000), one-yr patient (94% vs. 98%, p = 0.308), graft (92% vs. 98%, p = 0.168), and death-censored graft survival (98% vs. 100%, p = 0.317) comparing patients receiving MMF or SRL respectively. Patients receiving SRL showed worse safety outcomes, higher mean creatinine (1.6 ± 0.5 mg/dL vs. 1.4 ± 0.3 mg/dL, p = 0.007), higher proportion of patients with proteinuria (52.0% vs. 10.7%, p = 0.041), higher mean urinary protein concentrations (0.3 ± 0.5 g/L vs. 0.1 ± 0.2 g/L, p = 0.012), higher mean cholesterol concentration (217 mg/dL vs. 190 mg/dL, p = 0.030), and higher proportion of patients prematurely discontinued from randomized therapy (26% vs. 8%, p = 0.031).
Conclusion:  In patients receiving TAC, MMF produced similar efficacy but superior safety profile compared with SRL.  相似文献   
25.
Parotid neoplasms represent 3% of all head and neck tumours, and most are benign. Malignant tumours account for 14-25% of cases. Surgery is the treatment of choice, with options ranging from simple enucleation to radical parotidectomy. Sixteen patients presented with a history of a painless parotid lump. Diagnosis was achieved by ultrasound scan and MRI. Fifteen superficial parotidectomies and 1 nerve-sparing total parotidectomy were carried out. At histology, 10 pleomorphic adenomas, 4 Warthin's tumours, 1 lymphoepithelial cyst and 1 sebaceous adenocarcinoma were detected. In the single case of carcinoma, the 6 peri-glandular lymph nodes included in the specimen were metastasis-free. In 3 patients (20%) a transient paresis of the facial nerve was noted. The capsule appeared breached in only 1 case of pleomorphic adenoma. Four patients (26%) were diagnosed as suffering from Frey's syndrome. A salivary fistula was recorded in 2 patients (13%). During follow-up ranging from 3 to 96 months no tumour recurrence was recorded. Superficial parotidectomy seems to be the best choice of treatment for benign parotid tumours, since it allows complete excision of the tumour with sparing of the facial nerve. A radical procedure is, however, needed if malignancy is confirmed at frozen section.  相似文献   
26.
Gastrointestinal stromal tumours, though rare, are the most common mesenchymal neoplasms affecting the gastrointestinal tract. The most frequent sites of origin are the stomach and the small bowel, but they can occur anywhere in the gastrointestinal tract. Mesenteric and retroperitoneal forms have been described. The Authors present their personal experience with the treatment of gastrointestinal stromal tumours, with particular reference to the broad spectrum of clinical presentations and to the consequent therapeutic implications. We report on a retrospective analysis of the clinical presentations and courses, surgical management and pathological features of 27 patients with such tumours treated in our institution from 1993 to 2005. The variables analysed were the morphological and clinical characteristics of the tumours, demographic data, type of surgical treatment and postoperative course. Long-term survival was evaluated on the basis of clinical and/or telephonic follow-up in all patients. One tumour was located in the oesophagus, 14 in the gastric area, 7 in the small bowel, 2 in the colon-rectum, and 3 in the peritoneum. All patients studied received radical surgical treatment. In 7 patients surgical resection was extended to other organs. No postoperative mortality or major postoperative complications were observed. Twenty-two patients are still alive at follow-up. Three patients died as a result of neoplastic relapse and 2 of other causes. The median survival was 36 months. The actuarial 3- and 5-year survival rates were 89.7% and 67.8%, respectively. Our experience indicates that the site of origin of gastrointestinal stromal tumours with their broad spectrum of clinical presentations may influence both the therapeutic choice (neoadjuvant utilisation of imatinib mesylate) and the surgical treatment (wedge resection vs enlarged operations).  相似文献   
27.
The onset of diabetes mellitus following kidney transplantation or post-transplant diabetes mellitus (PTDM) is now recognized as being an increasingly common complication that is associated with poor graft and patient survival. The incidence and clinical correlates of PTDM in a Canadian kidney transplant population has not been examined and may vary based on differences in demographics (i.e. race). Furthermore, little information exists on the association of variables such as cumulative dose of corticosteroids and trough calcineurin inhibitor levels and PTDM. We examined all recipients of a kidney transplant in our center between 1995 and 2001 and found an overall PTDM rate of 9.8%. Five clinical factors were independently associated with PTDM: older recipient age, deceased donor, hepatitis C antibody status, rejection episode and use of tacrolimus (vs. cyclosporine). Furthermore, cumulative corticosteroid dose and calcineurin inhibitor trough level were not associated with PTDM. This study demonstrates that in a Canadian kidney transplant population that there is a significant risk of PTDM following kidney transplantation, and it is therefore advisable to minimize this risk.  相似文献   
28.
The role of magnetic resonance angiography (MRA) in the evaluation of vascular involvement was studied in 55 patients with abdominal neoplasms. A 2-D time-of-flight (TOF) technique was used in 18 patients. All patients underwent CT and MR examinations before MRA. Also, MR angiograms were compared with digital subtraction angiography in 22 cases, with Doppler US in 13 cases, and with surgical findings in 20 cases. In all patients with liver neoplasms (n = 29) MRA demonstrated the absence of flow in the infiltrated segments. Pericapsular neovascularization was observed in 12 patients. Portal vein involvement was correctly detected in 27 patients. In all cases MRA demonstrated the relationship between the tumor and venous structures. Portosystemic shunts were visualized in 20 of 21 patients with portal hypertension. Vena cava thrombosis (3 cases), compression (5 cases), and displacement (2 cases) were correctly demonstrated. In renal (n = 6) and adrenal gland (n = 3) tumors renal vein compression was correctly detected in 2 cases, displacement in 1 case, and thrombosis in 3 cases, with only 1 false-positive finding. In 7 patients with pancreatic tumors MRA demonstrated splenic vein thrombosis in 2 cases and compression in 2 cases, with one false-positive finding. Our results indicate that MRA provides precise information regarding venous vascular involvement in abdominal neoplasms, but preoperative arterial mapping is still problematic. Correspondence to: E. Squillaci  相似文献   
29.
Paraurethral leiomyoma is a rare, benign, hormone-dependent neoplasm of mesenchymal origin affecting women. The clinical evidence varies, but it tends to be asymptomatic or associated with the sensation of a foreign body; urinary symptoms are rarely described. The distinction among urethral, paraurethral, and anterior vaginal wall leiomyoma can be very difficult owing to their anatomic proximity. Excision of the mass is the recommended treatment, and the diagnosis is confirmed by the pathologic finding to rule out the presence of a sarcoma. A case of paraurethral leiomyoma associated with dysuria, dyspareunia, and obstructive voiding symptoms is reported.  相似文献   
30.

Background

Routine drainage after laparoscopic cholecystectomy is still debatable. The present study was designed to assess the role of drains in laparoscopic cholecystectomy performed for nonacutely inflamed gallbladder.

Methods

After laparoscopic gallbladder removal, 53 patients were randomized to have a suction drain positioned in the subhepatic space and 53 patients to have a sham drain. The primary outcome measure was the presence of subhepatic fluid collection at abdominal ultrasonography, performed 24?h after surgery. Secondary outcome measures were postoperative abdominal and shoulder tip pain, use of analgesics, nausea, vomiting, and morbidity.

Results

Subhepatic fluid collection was not found in 45 patients (84.9?%) in group A and in 46 patients (86.8?%) in group B (difference 1.9 (95?% confidence interval ?11.37 to 15.17; P?=?0.998). No significant difference in visual analogue scale scores with respect to abdominal and shoulder pain, use of parenteral ketorolac, nausea, and vomiting were found in either group. Two (1.9?%) significant hemorrhagic events occurred postoperatively. Wound infection was observed in three patients (5.7?%) in group A and two patients (3.8?%) in group B (difference 1.9 (95?% CI ?6.19 to 9.99; P?=?0.997).

Conclusions

The present study was unable to prove that the drain was useful in elective, uncomplicated LC.  相似文献   
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