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41.
Background: Between 1991 and November 1994, 18 patients with large, solitary, nonparasitic liver cysts underwent laparoscopic deroofing; the last 13 of them also received an omental transposition flap in addition. Methods: Using three to four trocars, the cystic contents were first aspirated, and the cyst derooted widely using diathermia. An omental transposition flap was fashioned and stapled into the cyst cavity itself. Results: Postoperative complications included one case of pulmonary atelectasis. Another patient developed a subhepatic bile collection which was aspirated percutaneously. On average, patients were discharged on the 4th (2–14) postoperative day. Follow-up was performed with abdominal ultrasound for 2–43 months (mean 19 months). There were two early cyst recurrences, both in cases without an omental transposition flap (overall recurrence rate, 11%; in patients with omental flap, 0). Conclusions: Deroofing in combination with an omental transposition flap is a safe and effective therapy for symptomatic solitary liver cysts and can be performed using minimal-access surgical techniques. Received: 19 January 1996/Accepted: 26 August 1996  相似文献   
42.
Platelet aggregation and thrombosis play an important role in the onset of acute coronary events. Regardless of the stimulus for activation, platelet thrombus formation is ultimately regulated through the IIb/IIIa receptor complex. The effects of oral administration of xemilofiban, a non-peptide mimetic of the RGDF sequence of the IIb/IIIa receptor complex, on thrombus formation were evaluated in a canine model. Xemilofiban significantly reduced platelet deposition on severely damaged arterial wall. Platelet deposition was reduced at both low (13 ± 1 from 56 ± 18 × 106 platelets cm−2; P  < 0.05) and high (23 ± 2 from 111 ± 21 × 106 platelets cm−2; P  < 0.01) shear rates. Platelet deposition was reduced to a monolayer as seen by electron microscopy (platelet–vessel wall interaction). Therefore, the availability of an orally active IIb/IIIa antagonist for chronic use may have significant value in preventing thrombus formation in those clinical situations associated with severe arterial injury, such as atherosclerotic plaque disruption.  相似文献   
43.
Early experience with laparoscopic abdominoperineal resection   总被引:4,自引:0,他引:4  
Background: Laparoscopic abdominoperineal resection (LAPR) has not been fully evaluated as a technique in the treatment of rectal and anal cancer or inflammatory bowel disease. The purpose of our study was to evaluate the early experience with laparoscopic abdominoperineal resection at Washington University Medical Center. Methods: A prospective analysis was performed on the first 21 patients undergoing the procedure at Washington University Medical Center. Indications for surgery included rectal cancer (14 patients), anal squamous cell cancer (four patients), inflammatory bowel disease (two patients), and anal melanoma (one patient). Results: The procedure was converted to open procedure in four patients (19%). The mean (±SEM) operative time and blood loss for completed and converted LAPR were 239 ± 11 min and 424 ± 43 ml, respectively. Postoperative hematocrit dropped a mean of 8.3% ± 1.2% SEM; five patients required blood transfusion (24%). Wound complication occurred in four patients (19%; three perineal, one trocar site). Bowel function returned after a mean of 3 days, and mean postoperative hospital stay for the completed LAPR group was 5 days. Mild pain was experienced by 81% of patients (17/21) while 19% (4/21) noted moderate pain, usually of the perineal wound. The mean duration of patient-controlled analgesia use was 2 days. During the 1–44-month follow-up, six patients (29%) died from cancer (stage III or IV at operation) and only one patient developed local recurrence in the pelvis (5%). There were no trocar-site implants of cancer. Furthermore, there was no relationship between prior abdominal operations, the amount of blood loss, postoperative drop of hematocrit, or blood transfusion requirement and the length of hospitalization or complication rates. Conclusion: Laparoscopic abdominoperineal resection is a feasible alternative to the conventional open technique in both cancer and colitis patients. Received: 23 April 1996/Accepted: 8 July 1996  相似文献   
44.
Background: Increasingly larger series of laparoscopic fundoplications (LF) are being reported. A well-documented advantage of the laparoscopic approach is shortened hospital stay. Most centers report typical lengths of stay (LOS) for LF of 2–3 days. Our success with LF with a LOS of 1 day led to an attempt at performing LF on an ambulatory basis. Methods: Sixty-one consecutive patients with appropriate criteria for LF underwent surgery at our institution. Patients were counseled by the authors as to the usual postop course and progression of diet. All patients received preemptive analgesia (PEA) consisting of perioperative ketorolac and preincisional local infiltration with bupivicaine. Anesthetic management included induction with propofol, high-dose inhalational anesthetics, minimizing administration of parenteral narcotics, and avoidance of reversal of neuromuscular blockade. Immediate postop pain management included parenteral ketorolac and oral hydro- or oxycodone. All patients were given oral fluids and soft solids after transfer from the recovery room to the postoperative observation unit. Two patients were excluded from ambulatory consideration due to excessive driving distance from our hospital. Another two were hospitalized for observation after experiencing intraoperative technical problems. Results: Of 57 patients in whom same-day discharge was attempted, there were three failures requiring overnight hospitalization: All were due to pain and nausea; one patient also suffered transient urinary retention. There were no adverse outcomes related to early discharge, and there were no readmissions. One patient returned to the emergency room after delayed development of urinary retention. Median time from conclusion of operation to discharge was less than 5 h. No patients expressed dissatisfaction with early discharge on follow-up interview. Conclusions: LF can be safely performed as an ambulatory procedure. Analgesic and anesthetic management should be tailored to minimize nausea and provide adequate pain control. Received: 1 April 1996/Accepted: 29 May 1997  相似文献   
45.
维胺酯-β-环糊精包合物的研究   总被引:6,自引:0,他引:6  
应用3因素8水平的均匀设计方法,优化出维胺酯-β-环糊精包合物最佳制备条件,所得包合物的包合率为99.3%,其表观稳定常数为1394M-1.  相似文献   
46.
Summary. The increasing spectrum of therapeutic options for tumors of the gastrointestinal tract has resulted in a refinement of the pretherapeutic diagnostic strategies. The diagnostic approach in surgical institutions that are focused on primary surgical resection will therefore be much less sophisticated than in institutions who propose a selective therapeutic approach based on the pretherapeutic tumor stage and prognostic parameters. Pretherapeutic assessment of the depth of tumor infiltration, i. e. the T-category, is essential because most further diagnostic and therapeutic decisions are based on this information. This can today be achieved with a high degree of accuracy by endoscopy and endoscopic ultrasonography. Early T-stages (T1–2) are usually an indication for primary surgical resection and, after exclusion of distant metastases, no further diagnostic studies are required. In patients with locally advanced esophageal, gastric or rectum tumors (T3–4) multimodal therapeutic concepts should be considered. This usually requires additional diagnostic studies. None of the available diagnostic imaging modalities today allows satisfactory pretherapeutic assessment of lymph node metastases. The assumed nodular status should therefore currently not influence therapeutic decisions. Essential is, however, the assessment of distant metastases, since the documentation of distant tumor spread will change the therapeutic approach to a palliative situation. Detailed histologic and molecular-biologic assessment of tumor characteristics is growing in importance. This not only provides therapeutically relevant information regarding tumor grading, but opens the door towards a modern molecular diagnostic approach. It can be expected that in the near future a vast amount of relevant prognostic information can be obtained from endoscopic tumor biopsies, which may soon alter our therapeutic concepts.   相似文献   
47.
Background: Kuzmak's gastric silicone banding technique is the least invasive operation for morbid obesity. The purpose of this study was to analyze the complications of this approach. Methods: Between September 1992 and March 1996, 185 patients underwent laparoscopic gastroplasty by the adjustable silicone band technique. A minimally invasive procedure using five trocars was performed. Results: In 11 patients exposure of the hiatus was impeded because of hypertrophy of the left liver lobe which led to conversion in eight patients and abortion of the procedure in three other patients. Anatomical complications: We observed two gastric perforations and one band slippage at the early stage, one infection and three rotations of the access port. Functional complications: There were eight (4%) cases of irreversible total food intolerance resulting in pouch dilation and eight cases (4%) of esophagitis. One fatality on the 45th day in a patient with a Prader-Willi syndrome. Conclusion: The most disturbing complications of gastric banding technique are gastric perforation and pouch dilation. Their incidence may be reduced by improving the technique and by considering pitfalls of the procedure. Received: 28 May 1996/Accepted: 25 July 1996  相似文献   
48.
The objective of this study is to investigate the effects of an acute necrotizing pancreatitis (ANP), without biliary obstruction, on the migrating motor complex (MMC), small bowel bacterial overgrowth (SBBO), bacterial translocation (BT) and infection of the pancreas simultaneously. Rats were divided into four groups: mild pancreatitis, control, ANP and sham operated control. Jejunal myoelectrodes were used to measure MMCs. Blood, peritoneal fluid, bile, and abdominal organs were harvested for microbial culturing 72 h after induction of pancreatitis. The splenic portion of the pancreas was taken for histology. During ANP the MMC cycle length was significantly increased from 14.1 +/- 0.2 to 22.4 +/- 1.9 min (P < 0.05). The duodenum of ANP rats was in contrast with the other groups characterized by Enterobacteriacae (> 3 log 10 CFU g-1 in seven of 12 rats, P < 0.05). A positive correlation (r = 0.78, P < 0.01) existed between duodenal Gram-negative and anaerobic flora and the MMC cycle. Correlation between MMC cycle length and BT to the pancreas was positive as well (r = 0.70, P < 0.01). A positive correlation (r = 0.85, P < 0.01) was found between the severity of pancreatitis and duodenal bacterial overgrowth. During ANP without biliary obstruction, the jejunal MMC is disturbed and consequently SBBO occurs. The correlation between the severity of pancreatitis, the disturbance of the MMC and SBBO suggests an important pathophysiological role of the proximal small bowel in the infection of pancreatic necrosis.  相似文献   
49.
BACKGROUND AND OBJECTIVES: To evaluate the experience with laparoscopic nephrectomy in a large county hospital and perform a cost comparison between uncomplicated open and laparoscopic nephrectomy. METHODS: Eleven consecutive patients who underwent an uncomplicated laparoscopic nephrectomy in a large county hospital were compared with 8 patients who underwent uncomplicated open nephrectomy during the same period. Patient charts and corresponding billing records were reviewed to determine overall hospitalization cost and individual cost components. RESULTS: No perioperative complications occurred in either the laparoscopic or open group, and no statistically significant differences existed between groups with regard to patient demographics or operative parameters. The overall operating room costs favored the open nephrectomy group by dollars 1070 (P=0.003). However, the overall cost of hospitalization, surgeon professional fees, duration of hospitalization, room and board costs, laboratory, and radiology costs, pharmacy costs, intravenous solution and infusion pump costs all significantly favored the laparoscopic patient group. The mean difference in overall hospital cost between laparoscopic and open nephrectomy was dollars 1211 in favor of laparoscopy (P=0.037). CONCLUSIONS: Our experience with laparoscopic nephrectomy in a large county hospital demonstrates a clear economic advantage in favor of the laparoscopic approach. Given limited funding for public hospitals and a clear patient benefit, laparoscopic nephrectomy should constitute first-line therapy when nephrectomy is indicated.  相似文献   
50.
Twenty-nine patients with diffuse liver disease were examined by ultrasound, CT and MRI. MRI was performed using T1- and T2-weighted spin-echo sequences as well as fast gradient-echo-sequences. The paramagnetic contrast agent Gd-DTPA was applied intravenously (0.1 mmol/kg). in patients with hepatitis, MRI could be used in guiding liver biopsies as inflammatory changes were clearly delineated. CT and ultrasound were superior to MRI in the detection of focal or diffuse fatty degeneration. On the other hand MRI was more helpful in differentiating fatty changes and neoplasm. In liver cirrhosis, fibrotic changes were most clearly demonstrated by MRI. In patients suffering from hemochromatosis MRI offers advantages over CT and ultrasound in the diagnosis and follow up due to the paramagnetic properties of iron, resulting in a reduction in signal intensity. In patients with Wilson's disease a characteristic pattern of parenchymal changes was seen. Administration of Gd- DTPA contributes additional information about perfusion conditions in the liver parenchyma, however this information was not of diagnostic relevance in the cases we studied. Correspondence to: T.J. Vogl  相似文献   
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