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141.

Background

Migration is the most common complication of the fully covered metallic self-expanding esophageal stent (SEMS). This study aimed to determine the potential preventive effect of proximal fixation on the mucosa by clips for patients treated with fully covered SEMS.

Methods

In this study, 44 patients (25 males, 57%) were treated with fully covered SEMS including 22 patients with esophageal stricture (4 malignant obstructions, 6 anastomotic strictures, and 12 peptic strictures) and 22 patients with fistulas or perforations (10 anastomotic leaks, 4 perforations, and 8 postbariatric surgery fistulas). The Hanarostent (n?=?25), Bonastent (n?=?5), Niti-S (n?=?12), and HV-stent (n?=?2) with diameters of 18 to 22?mm and lengths of 80 to 170?mm were used. Two to four clips (mean, 2.35?±?0.75 clips) were used consecutively in 23 patients to fix the upper flared end of the stent with the esophageal mucosal layer. Stent migration and its consequences were collected in the follow-up assessment with statistical analysis to compare the patients with and without clip placement.

Results

No complication with clip placement was observed, and the retrieval of the stent was not unsettled by the persistence of at least one clip (12 cases). Stent migration was noted in 15 patients (34%) but in only in 3 of the 23 patients with clips (13%). The number of patients treated to prevent one stent migration was 2.23. The predictive positive value of nonmigration after placement of the clip was 87%. In the multivariate analysis, the fixation with clips was the unique independent factor for the prevention of stent migration (odds ratio, 2.3; 95% confidence interval, 0.10?C0.01; p?=?0.03).

Conclusions

Anchoring of the upper flare of the fully covered SEMS with the endoscopic clip is feasible and significantly reduces stent migration.  相似文献   
142.
MicroPET imaging of prostate cancer in LNCAP-SR39TK-GFP mouse xenografts   总被引:4,自引:0,他引:4  
BACKGROUND: The aim of this study was to develop models that allow serial, noninvasive imaging of human prostate cancer cells in immunodeficient mice using a dedicated small animal positron emission tomography scanner (microPET). METHODS: LNCaP tumor cells were stably transduced ex-vivo with the mutant herpes simplex virus type 1 thymidine kinase (HSV-sr39tk) PET reporter gene and green fluorescent protein (GFP). The stably transduced LNCaP cells were then enriched via fluorescent cell sorting and implanted into SCID mice. Beginning 2 weeks after tumor cell inoculation, mice were repeatedly scanned by microPET performed 1 hr after tail-vein injection of approximately 200 muCi Fluorine-18 labeled penciclovir ((18)F-FHBG). PET-images were correlated to tumor size, % injected dose (ID)/g tumor tissue, PSA levels, autoradiography, and histology. RESULTS: Monitoring LNCaP xenografts using microPET and our reporter gene approaches is feasible. MicroPET was capable of detecting subcutaneous tumors as small as 3 mm in diameter (approximately 0.2% ID/g). The magnitude of (18)F-FHBG-uptake in PET-images correlated with the tumor volumes and the serum PSA levels. Other non-HSV1-TK-specific tracers were also studied. While (18)F-flurodeoxyglucose ((18)F-FDG) gave poor imaging results in LNCaP cells, (11)C-acetate gave satisfactory images. CONCLUSIONS: We demonstrated the feasibility of monitoring prostate cancer xenografts in a mouse model using microPET and the HSV1-sr39tk PET reporter gene/(18)F-FHBG reporter probe system. Extension of this approach may allow repetitive imaging of tumor metastases.  相似文献   
143.
OBJECTIVE: Calcium and vitamin D deficiency is common in older individuals, particularly those who live in nursing homes, and increases the risk of osteoporosis and fractures. METHODS: We conducted a randomized double-blind placebo-controlled study of combined supplementation with 500 mg of elemental calcium, as carbonate, and 400 IU of vitamin D bid for 12 months in women older than 65 years of age with vitamin D deficiency, defined as serum 25(OH)D concentrations 相似文献   
144.
145.
Caudal ropivacaine and neostigmine in pediatric surgery   总被引:6,自引:0,他引:6  
BACKGROUND: Neostigmine has been added to local anesthetics for different nerve blocks. This study was conducted to evaluate effects of neostigmine when added to ropivacaine for caudal anesthesia. METHODS: We studied children, aged 1-5 yr, undergoing inguinal hernia and hypospadias surgery. After standard induction of anesthesia, Group I received 0.2% ropivacaine 0.5 ml/kg and Group II received 0.2% ropivacaine 0.5 ml/kg with 2 microg/kg neostigmine via the caudal route. Heart rate, mean arterial pressure, and pulse oximetry were recorded before induction, after induction, and then every 10 min after caudal anesthesia. Hemodynamic, Toddler-Preschooler Postoperative Pain Scale pain score, and sedation score values were recorded 30 min after extubation and at hours 2, 4, 6, 12, and 24. A pain score greater than 3/10 resulted in administration of rectal paracetamol. RESULTS: There were no differences between the groups in demographic and hemodynamic data, duration of surgery and anesthesia, time to extubation, or sedation scores. The pain scores were significantly lower in Group II at 6 and 12 h (P < 0.05). Time to first analgesic requirement was statistically prolonged in Group II (19.2 +/- 5.5h) when compared with Group I (7.1 +/- 5.7 h) (P < 0.05). Total analgesic consumption was statistically larger in Group I (174 +/- 96 mg) when compared with Group II (80 +/- 85.5 mg) (P < 0.05). The incidence of vomiting (3 patients in Group II and 1 patient in Group I) was not statistically significantly different. CONCLUSIONS: The authors found that a single caudal injection of neostigmine when added to ropivacaine offers an advantage over ropivacaine alone for postoperative pain relief in children undergoing genitourinary surgery.  相似文献   
146.
We describe five primary tumors of the adenohypophysis featuring mitochondrion-rich spindle cells. The patient ages ranged from 53 to 71 years (mean 61.6 years); two were female. All presented with panhypopituitarism. Two also had visual field defect. On neuroimaging all tumors showed suprasellar extension and were indistinguishable from pituitary adenoma. None showed imaging or operative evidence of dural involvement. All were gross totally removed: four by transsphenoidal surgery and one by frontal craniotomy. Follow-up ranged from 2 to 68 months (mean 35.4 months). No recurrences were noted. The clinical workup was noncontributory in all but two patients: one (case no. 4) with an oncocytic thyroid adenoma and another (case no. 5) with squamous carcinoma of both the uterine cervix and of vocal cord. Histologically, the five tumors were composed mainly of fascicles of spindle cells with eosinophilic, granular cytoplasm. Mitoses were rare and necrosis was absent. Neoplastic cells were immunoreactive for vimentin, epithelial membrane antigen, S-100 protein, and galectin-3. Stains for pituitary hormones, synaptophysin, chromogranin, glial fibrillary acidic protein, cytokeratin CAM5.2, smooth muscle actin, CD34, and CD68 were negative. No thyroglobulin immunoreactivity was noted in the tumor of case no. 4. Ultrastructurally, the neoplastic cells contained numerous mitochondria with lamellar cristae. The neoplastic cells were linked by intermediate junctions and desmosomes. No secretory granules were noted. The histologic, immunohistochemical, and fine structural features of these tumors were unlike those of pituitary adenoma or any other primary sellar tumor. A derivation from adenohypophyseal folliculostellate cells is suggested.  相似文献   
147.
Acute acalculous cholecystitis remains a diagnostic challenge in critically ill trauma patients. Laboratory studies are nonspecific and associated injuries or mental status changes may mask clinical signs and symptoms. We conducted a retrospective study to assess the utility of ultrasound in the diagnosis of acute acalculous cholecystitis. We hypothesized that ultrasound is inadequate as a screening tool for acute acalculous cholecystitis. The abdominal ultrasounds of all patients undergoing evaluation for acute acalculous cholecystitis in a 40-month period at our Level I trauma center were reviewed. Thickened gallbladder wall, pericholecystic fluid and emphysematous gallbladder were considered positive sonographic criteria. Sludge, cholelithiasis, and hydrops were considered suggestive. Patients who did not undergo cholecystectomy had their gallbladders evaluated either during subsequent laparotomy or at autopsy or they were discharged from the hospital without need for intervention. Sixty-two patients were included. Twenty-one patients underwent cholecystectomy for presumed acute acalculous cholecystitis. The data revealed a sensitivity of 30 per cent (6/20) and a specificity of 93 per cent (39/42) for ultrasound evaluation. Twenty patients had subsequent hepatobiliary scans [hepato-iminodiacetic acid (HIDA)] with a sensitivity of 100 per cent (12/12) and specificity of 88 per cent (7/8). Our data do not support ultrasound as a reliable routine screening tool for acute acalculous cholecystitis. Despite its convenience as a bedside procedure ultrasound has insufficient sensitivity to justify its use and a more sensitive diagnostic tool should be used.  相似文献   
148.
Our experience with tissue expansion on a series of 50 cases in Vietnam   总被引:1,自引:0,他引:1  
The authors reviewed their experience with tissue expansion from July of 1995 to December of 1999 at Hanoi Plastic Surgery Center. A total of 75 tissue expanders of various sizes were placed in 50 consecutive patients (16 men and 34 women) for the reconstruction of secondary defects (burn scars, skin graft scars, hypertrophic scars, keloids, capillary hemangioma, congenital nevi and micotia). The average age of patients was 21 years. The tissue expansion protocol was used in clinical as well as common principle. The main technical details are modified in this procedure by the authors: type of intralesional incision for expander insertion, closing of wound incision by three layers, evacuation of the liquid in the prosthesis pocket, injection with antibiotic solution and expanded flap capsulectomy. The complications rate was 10.6% (8 complications in 75 expanders). The most common complications consisted of infection, hematoma, exposure of valve, dehiscence of incision, necrosis of the distal expanded flap. The overall failure rate was 8%. Thus our modified surgical details allowed us to decrease the major complications and to achieve the best possible functional and aesthetic results.  相似文献   
149.
Tumor thrombus in major vasculature is a frequent finding with a poor long-term prognosis in patients with hepatocellular carcinoma (HCC). The utility of surgical resection is still controversial. This study compared morbidity and survival after resection for HCC with and without tumor thrombus. Data of 108 patients who underwent major hepatic resection for HCC were prospectively recorded. Patients were divided into two groups. The venous thrombectomy (VT) group included 26 patients who had HCC with tumor thrombus in the portal or hepatic veins. The matched control group included 82 patients who had HCC without tumor thrombus. Surgical technique, early outcome, and late survival were analyzed in each group. Multivariate analysis was performed to assess the prognostic value of this feature. Surgical technique was comparable in the VT and control group with regard to extent of hepatectomy, procedure duration, and transfusion requirements. Early postoperative outcome was also comparable. Actuarial survival at 1, 3, and 5 years was 38%, 20%, and 13%, respectively, in the VT group (median: 9 months) versus 74%, 56%, and 33%, respectively, in the control group (median: 41 months). In the subgroup of patients with tumor thrombus limited to the portal vein, actuarial survival at 1, 3, and 5 years was 50%, 26%, and 17%, respectively, (median: 12 months) and two patients lived longer than 5 years. Multivariate analysis showed that incomplete resection, alphafetoprotein level greater than 100 N, more than two tumor nodules, and tumor thrombus in major vasculature were independent factors of poor prognosis. Survival after resection for HCC with tumor thrombus in the major vasculature is poorer than after resection for HCC without tumor thrombus. However, an aggressive surgical strategy can provide significant survival with comparable morbidity in selected cases, that is, tumor thrombus located in the portal vein only and expected complete resection of the lesions.  相似文献   
150.
BACKGROUND: Although numerous methods of postoperative analgesia have been investigated in an attempt to improve pain control after total knee arthroplasty, parenteral narcotics still play a major role in postoperative pain management. Local anesthetics have the advantage of blocking pain conduction at its origin and minimizing the systemic side effects associated with postoperative narcotic use. This study was performed to evaluate the benefits and safety of a multimodal analgesia protocol that included periarticular injection of large doses of local anesthetics in patients undergoing total knee arthroplasty. METHODS: We compared morphine consumption during the first twenty-four hours after unilateral total knee arthroplasty in forty-two patients who had been randomized to receive either (1) a perioperative infiltration mixture, consisting principally of local anesthetic, and self-administered morphine or (2) self-administered morphine only. Narcotics consumption, pain control, medication-related side effects, plasma levels of the local anesthetic (ropivacaine), and postoperative rehabilitation were monitored. RESULTS: Although there was high satisfaction and good pain control in both groups, morphine consumption was significantly lower in the local analgesia group than it was in the control group (28.8 +/- 17.4 mg compared with 50.3 +/- 25.4 mg twenty-four hours after surgery, and 46.7 +/- 19.4 mg compared with 68.6 +/- 38.6 mg forty hours after surgery). Both groups achieved a similar amount of knee flexion on the fifth postoperative day. Over the five-day period after the procedure, the patients in the local analgesia group reported a total of 2.6 +/- 3.9 hours of nausea compared with 7.1 +/- 12.2 hours in the control group. No complications related to the infiltration of the local anesthetic were observed, and all plasma concentrations of the local anesthetic were below the toxic range. CONCLUSIONS: This multimodal perioperative analgesia protocol that included infiltration of a local anesthetic offered improved pain control and minimal side effects to patients undergoing total knee arthroplasty. Our study also confirmed the safety of the protocol.  相似文献   
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