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81.
Hon SS  Ng SS  Chiu PW  Chan FK  Ng EK  Li JC  Lee JF  Leung KL 《Surgical endoscopy》2011,25(12):3923-3927

Background  

Transanal local excision (LE) is a well-established treatment option for early rectal neoplasms not amenable to complete colonoscopic removal. Endoscopic submucosal dissection (ESD) has been introduced recently as a novel procedure that enables en bloc resection of large rectal neoplasms. To date, no report comparing the two approaches can be found in the literature. This study aimed to compare the short-term clinical outcomes between ESD and LE for early rectal neoplasms.  相似文献   
82.
OBJECTIVE: The aim of this study was to evaluate the incidence of postoperative deep vein thrombosis (DVT) in Chinese patients who underwent laparoscopic resection of rectal or sigmoid cancer in the absence of thromboprophylaxis. METHODS: Patients with adenocarcinoma of the sigmoid colon or rectum scheduled for laparoscopic resection were recruited. Neither chemoprophylaxis nor mechanical methods against DVT were employed. They were scheduled to have routine duplex ultrasound of both lower limbs perioperatively. RESULTS: In a 12-month period, 50 patients were recruited. Postoperative DVT occurred in 19 (38%) patients. None needed anticoagulation. Complete resolution of the thrombus was noted in 10 (53%) patients 12 weeks after operation, and in six patients 36 weeks after operation. Female sex was identified as being associated with a higher incidence of DVT. Age, smoking, preoperative neoadjuvant chemoirradiation, preoperative metastasis, duration of operation, conversion and postoperative complications did not appear to be risk factors for DVT. CONCLUSION: The incidence of asymptomatic calf vein DVT is relatively high after laparoscopic resection for rectosigmoid cancers in the Chinese population. However, complete resolution occurred without the use of anticoagulant therapy in the majority of cases. It is thus difficult to advocate the routine use of anticoagulant prophylaxis.  相似文献   
83.
84.
Summary  Haemorrhage from rupture of petrous ICA aneurysm can be life threatening and emergency treatment is required. We report 2 cases of radiation-induced petrous internal carotid artery (ICA) aneurysm presenting with acute haemorrhage (epistaxis and otorrhagia) after radiotherapy (RT) for nasopharyngeal carcinoma (NPC). Both patients had a history of RT treatment for NPC. The first patient, a 54-year-old man, presented with sudden severe epistaxis and haemorrhagic shock. The second patient, a 35-year-old man, presented with episodes of severe otorrhagia. The first patient was immediately resuscitated. Obliteration of the aneurysm was performed by endovascular occlusion of the ICA with Guglielmi detachable coils and fibered platinum coils. For the second patient, the aneurysm was treated by deploying a self-expandable stent across the aneurysm neck. In an emergency situation, ruptured petrous ICA aneurysm can be treated with endovascular occlusion of the ICA with microcoils if there is a good collateral blood flow. Alternatively, the aneurysm can be treated by deployment of a stent, which can induce stasis and eventual thrombosis of the aneurysm.  相似文献   
85.
BACKGROUND: The use of volatile anesthetics for maintenance of anesthesia can enhance the action of non-depolarizing muscle relaxants and interfere with the reversal of neuromuscular blockade. In this study, we studied the antagonism of rocuronium with edrophonium-atropine during propofol- versus sevoflurane-based anesthesia. METHODS: Following induction of anesthesia with propofol (2-2.5 mg kg(-1), i.v.) and fentanyl (1-2 microg kg(-1) i.v.), rocuronium 0.6 mg kg(-1) i.v. was administered to facilitate tracheal intubation. Patients were then randomized to receive either a propofol infusion (100 microg kg(-1) min(-1)) or sevoflurane (1.0%, end-tidal) in combination with nitrous oxide 66% for maintenance of anesthesia. Neuromuscular blockade was monitored using electromyography at the wrist, and reversed with edrophonium 1.0 mg kg(-1) and atropine 0.015 mg kg(-1) when the first twitch hight (T1) of the train-of-four (TOF) stimulation recovered to 25% of the baseline value. Anesthetic maintenance with propofol or sevoflurane was continued following reversal until a TOF ratio of 0.7 was attained. RESULTS: The clinical duration of action (i.e., time to 25% T1 recovery) was similar during both propofol- (39.3+/-14.6 min) and sevoflurane-based (48.1+/-19.7 min) anesthesia. However, the reversal time from 25% T1 to TOF ratio of 0.7 was significantly longer with sevoflurane [Median 2.8 (range 0.5-18.8) min] compared with propofol [1.5 (0.75-3) min] (P<0.05). CONCLUSIONS: We conclude that the clinical duration of action after a single dose of rocuronium, 0.6 mg kg(-1) i.v., was similar during both propofol- and sevoflurane-based anesthesia. However, the reversal of rocuronium-induced residual blockade was slower and more variable in the presence of sevoflurane.  相似文献   
86.
OBJECTIVE: To evaluate the stage- and grade-specific survival rate in patients with upper urinary tract (UUT) transitional cell carcinoma (TCC) after open (ONU) or hand-assisted laparoscopic nephroureterectomy (LNU) with bladder-cuff excision. PATIENTS AND METHODS: From January 1998 to April 2005, 143 patients with UUT-TCC were treated with either ONU or LNU and enrolled in the study. The peri-operative data were collected by retrospective chart review. The recurrence, metastasis and survival rate were calculated. RESULTS: The 5-year disease-specific survival of patients with pT1 disease was 88.1% after ONU and 92.0% after LNU (P = 0.745); the respective values for patients with pT2 were 11/17 and 12/15 (P = 0.874), and for pT3 were six/11 and 12/15 (P = 0.476). The incidence of bladder recurrence within 2 years after surgery was 24.7% for ONU and 19.7% for LNU (P = 0.475). CONCLUSION: The results were similar after ONU or LNU with bladder-cuff excision; bladder-cuff excision using a hand-assisted device is effective and serves as a treatment option for patients with UUT-TCC.  相似文献   
87.
In orthotopic liver transplantation (OLT), tolerance is induced in a certain combination of donors and a recipient in rats and, in some clinical cases, rejection has not occurred in OLT patients after weaning off immunosuppression. However, this mechanism has not yet been elucidated. Among our cases of liver transplantation (LTx), one OLT patient (Patient A) has not required immunosuppressive drugs for the last 5 years, following post-transplant lymphoproliferative disease (PTLD). This patient's serum interleukin-2 levels were undetectable following withdrawal of immunosuppressants. The same serum taken after discontinuing the immunosuppressants inhibited concanavalin A blast cultured cells and up-regulated the IL-4/IFN-gamma gene expression ratio. These results suggested that other proteins were induced following withdrawal of immunosuppressants. Proteomic assay demonstrated 12 differentiated spots exclusive to this patient where immunosuppressants have been discontinued. Haptoglobin, found to have immunosuppressive activity in vitro, may play an important role in the maintenance of drug-free tolerance as a natural immunological suppressor after cessation of immunosuppression. Proteomic analysis will allow us to develop a novel weaning protocol for patients on long-term immunosuppression to avoid major immunosuppressant-related complications.  相似文献   
88.

Purpose

The tibial drill-guide angle in anterior cruciate ligament (ACL) reconstruction influences the tunnel placement and graft-tunnel force, and is potentially associated with post-operative tunnel widening. This study aimed to examine the effect of the drill-guide angle on the stress redistribution at the tibial tunnel aperture after anatomic single-bundle ACL reconstruction.

Methods

A validated finite element model of human knee joint was used. The tibial tunnel with drill-guide angle ranging from 30° to 75° was investigated. The post-operative stress redistribution in tibia under the compressive, valgus, rotational and complex loadings was analysed.

Results

Compressive loading played a leading role on the stress redistribution at intra-articular tibial tunnel aperture. After ACL reconstruction, stress concentration occurred in the anterior and posterior regions of tunnel aperture while stress reduction occurred in the lateral and posteromedial regions under the compressive loading. Stress redistribution was partially alleviated by using the drill-guide angle ranging from 55° to 65°.

Conclusions

The present study quantified the effect of bone tunnel drill-guide angle on the post-operative stress redistribution. This phenomenon potentially contributed to tunnel widening. A tunnel drill-guide angle ranging from 55° to 65° was proposed based on the biomechanical rationale. It could serve as a helpful surgical guide for ACL reconstruction.  相似文献   
89.

Background

High-intensity focused ultrasound is a promising, nonoperative treatment for benign thyroid nodules. Our study aimed to compare treatment outcomes of single-session high-intensity focused ultrasound ablation with open lobectomy after propensity score matching.

Methods

After propensity matching, we compared treatment-related morbidity, treatment time, duration of hospitalization, improvement in symptom score, cost, and acoustic parameters of consecutive patients who underwent high-intensity focused ultrasound ablation or lobectomy. All eligible patients completed the computerized, multidimensional voice program and Voice Handicap Index questionnaire before, and 3 and 6 months after treatment.

Results

The matched cohort comprised 154 patients (77 in each group). Although treatment-related morbidity was comparable between the two groups (P?=?.368), treatment time (P <.001), duration of hospitalization (P <.001), and medical cost (P <.001) were less in the high-intensity focused ultrasound group. After high-intensity focused ultrasound ablation, the 6-month nodule shrinkage (mean ± SD) was 64% ± 26% and the 6-month symptom improvement score was comparable with lobectomy (P?=?.283). At 6 months, none of the acoustic parameters were changed from the baseline in both groups (P >.05), and the Voice Handicap Index questionnaire did not differ between the two groups (P >.05).

Conclusion

Despite having similar treatment-related morbidity and voice outcomes, there were possibly some advantages with high-intensity focused ultrasound during open lobectomy, including the avoidance of a neck scar, shorter treatment time and duration of hospitalization, and lower medical cost.  相似文献   
90.
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