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71.
Fundus-first laparoscopic cholecystectomy   总被引:1,自引:1,他引:0  
Removal of the gallbladder with commencement of dissection at the fundus is well recognized as a safe technique during difficult open cholecystectomy because it minimizes the risks of damage to the structures in or around Calot's triangle. We report here the routine employment of liver retractors and fundus-first dissection during laparoscopic cholecystectomy (LC) as an alternative to techniques previously described.Retraction of the liver and fundus-first dissection was used in 53 patients who underwent laparoscopic cholecytectomy. There were 16 male and 37 female patients. Seven were operations performed during an acute admission and 20 had moderate or severe adhesions involving the gallbladder. Thirteen patients had a preexisting abdominal incision.The procedure was successful in 52 patients (98%), but in one patient it was converted to open operation because of dense adhesions. Median duration of operation was 90 min (range 35–240 min). There was no mortality and two complications (persistent right upper quadrant pain for 2 weeks after operation and bile leakage from the gallbladder bed).The facility to retract the liver and carry out a fundus-first dissection extends techniques developed for open surgery into the laparoscopic arena. It offers the surgeon the safety and versatility during laparoscopic cholecystectomy that it confers during conventional open surgery.Presented at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES), Nashville, Tennessee, USA, 18–19 April 1994  相似文献   
72.
Since its conception, several techniques have been described for laparoscopic appendicectomy. We describe a technique which utilizes a 5-mm bipolar forceps designed to coagulate and cut tissues at the same time; 50 pediatric patients underwent laparoscopic appendicectomy for acute appendicitis using this stripping and teasing technique. No bleeding complications occurred. There were only two postoperative abscesses in the series. We believe that the bipolar laparoscopic striptease appendicectomy technique as developed by the senior author is safe, quick, and effective, even for severe appendicitis.  相似文献   
73.
Ion channel current amplitudes () and open probabilities (P o) have been analysed so far by defining a 50% threshold to distinguish between open and closed states of the channels. With this standard method (SM) it is very difficult or even impossible to analyse channels of different size in one membrane patch correctly. A stochastical model, named the hidden Markov model (HMM), separates between observation noise and the stochastic process of opening and closing of ion channels. The HMM allows the independent analysis of , P o, and mean dwell times () of different channels in one membrane patch, without defining threshold levels. Using this method errors in the analysis are not summarized like in the SM because all different analysing procedures (e. g. filtering, setting of threshold, fitting processes) are done in one step. Two different K+ channels in excised basolateral membranes of the cortical collecting duct of rat (CCD) were analysed by the SM and the HMM. The value of the intermediate-conductance K+ channel (i-K+) was 3.9±0.1 pA (SM) and 3.8±0.2 pA (HMM) for 11 observations. The P o value of this channel was 10.2±4.2% (SM) and 10.1±4.0% (HMM). The mean values were 5.4±0.6 ms for the open state and 9.6±2.2 ms and 145±21 ms for the closed states (SM) and 7.8±1.1 ms, 7.7±0.9 ms and 148±24 ms (HMM), respectively. For seven small-conductance K+ (s-K+) channels, which were found in the same membrane patches as the i-K+, an accurate analysis of P o and was not possible with the SM. The value was 1.0±0.1 (SM), 0.9±0.1 (HMM) pA. P o was 16.6±4.6%, the open value was 11.1±2.8 ms, and the closed value was 34.9±8.5 ms. The HMM allows the analysis of single-channel currents, P o, and mean values when different or more than one ion channel(s) are colocalized in one membrane patch. Where analysis with the SM was possible results did not significantly differ from those obtained with the HMM. Thus for this kind of analysis the method of setting a 50% threshold appears justified.  相似文献   
74.
OBJECTIVE: To perform a retrospective analysis of patients with nasopalatine duct cysts (NPDC) in Brazil and compare with previous analyses. MATERIALS AND METHODS: The files of the Laboratory of Oral Pathology (Minas Gerais Federal University) from 1966 to 1997 were reviewed. Demographic, clinical and histologic data of patients with nasopalatine duct cysts were collected. RESULTS: The mean age of patients with nasopalatine duct cysts at the time of diagnosis was 37.4 years and with a predilection for males. The majority of cases were asymptomatic. Histologically, non-keratinized stratified squamous epithelium alone or in combination with other epithelia was observed in 93% of the cases. Recurrence was not recorded. CONCLUSION: The demographic, histopathological, radiographic, and clinical data of the NPDC in our series are similar to previous studies in other populations.  相似文献   
75.
目的观察胰高血糖素对胆道梗阻大鼠肝脏葡萄糖和酮体合成作用的影响。方法大鼠胆道结扎48小时后,用胶原酶灌流后分离肝细胞,加入胰高血糖素温育,用分光光度计按标准酶学方法检测葡萄糖、乙酰乙酸和三羟基丁酸。结果在基础或最大刺激条件下,加胰高血糖素结扎组、假手术组葡萄糖异生均明显大于未加胰高血糖素组(P<0.05),加胰高血糖素对结扎组和假手术组的酮体异生无促进作用。结论胰高血糖素对胆道梗阻48小时大鼠肝细胞的糖异生存在有意义的刺激作用,对酮体异生则无刺激作用  相似文献   
76.
An intraabdominal abscess developed from a retained fecalith following laparoscopic appendectomy. We discuss the prevention and management of retained fecaliths in light of the numerous reports of retained gallstones. Received: 24 January 1997/Accepted: 17 November 1997  相似文献   
77.
Changes in hemostasis after laparoscopic cholecystectomy   总被引:6,自引:3,他引:3  
Background: The aim of this work was to study hemostasis in laparoscopic cholecystectomy in order to determine if there are any changes that indicate a greater risk of thrombosis. Methods: The study was carried out in 20 patients who underwent laparoscopic surgery for noncomplicated cholelithiasis. The average age was 59.4 years (range, 34–77). A total of 75% were female. Mean operation time was 70 min (ranges 35–120). Pneumoperitoneum at 14 mmHg was performed on all patients, who were positioned in the 30° reverse Trendelenburg position. Postoperative mobilization was acheived in 24 hs and patients were discharged 48 hs after the operation. The control group was composed of 12 patients, who were evenly distributed by age, sex, and length of surgery. These patients underwent Bassini herniorraphy for inguinal hernia without any complications or relapse. The following hemostatic parameters were studied: prothrombin activity (PA), activated partial thromboplastin time (APTT), fibinogen (Fg), anti-thrombin III (ATIII), plasma fibrinolytic activity (PFA), euglobulin fibrinolytic activity (EFA), and D-dimer (D-D). Samples were obtained at the following times: (a) under basal conditions the day before surgery, (b) preoperatively, (c) at the end of the operation, (d) 24 hs after the operation, and (e) On the 7th day following the operation. Results: No patient showed any clinical manifestations of thromboembolic disease immediately after surgery or during a medium follow-up period of 16 months (range, 15–18 months). All hemostatic parameters values were within normal range in the basal samples of both groups. In both groups, the mean value of PA showed a significant decrease (p < 0.05) in the second, third, and fourth basal samples, returning to normal levels by the fifth determination. The mean value of fibrinogen decreased slightly in the second and third samples, increasing significantly with respect to the fourth and fifth determinations in both groups (p < 0.05). The mean value of APTT in both groups was slightly enhanced in the second and third determinations in relation to the first and fifth. The global activity of fibrinolysis (PFA and EFA) increased significantly in the third sample with respect to the other determinations in the group who had laparoscopic surgery (p < 0.005). Only EFA increased in the control group (p < 0.05). D-D decreased in the preoperative second determination followed by a significant enhancement immediate postoperatively (third), and 24 hs (fourth) (p < 0.05); it returned to normal basal values on the seventh day. No significant differences were found between the two groups. Conclusions: These results indicate that laparoscopic cholecystectomy leads to no greater activation of plasma coagulation than low-risk surgery. On the contrary, the increase of fibrinolytic activity in plasma would extend a certain degree of hypocoagulability during surgery, maintaining it for 24 hs and thus possibly reducing thromboembolic risk in patients undergoing this type of surgery. Received: 25 February 1998/Accepted: 18 August 1998  相似文献   
78.
The use of a large synthetic mesh for laparoscopic repair of significant ventral abdominal wall defects may be accompanied by technical difficulties resulting from improper orientation and positioning of the mesh over the defect. We suggest a technique based on initial fixation of the mesh center to the central point of the defect, and subsequent centrifugal attachment of the mesh to the abdominal wall. This technique is advantageous because it leads to precise orientation and positioning of the synthetic patch and to significant reduction of the time needed for its reinforcement over and around the defect. Received: 25 September 1998/Accepted: 27 November 1998  相似文献   
79.
Proliferating cell nuclear antigen (PCNA) and transforming growth factor (TGF) are considered as markers of cell proliferation. The expression of PCNA and TGF was evaluated immunohistochemically using anti-PCNA antibody and TGF in 31 patients with biliary atresia (BA) (15 jaundice-free and 16 with persistent jaundice) and 6 control infants. The labeling indices (LI) for PCNA- and TGF-positive bile-duct epithelium in BA were 14.1±14.0% and 51.4±33.7%, respectively, which was significantly higher than in the controls (P <0.01). In BA, the number of PCNA-immunoreactive cells was higher in the peripheral bile ductules than in the central bile ducts of the portal tract (P <0.01). LI was not related to patient age at the time of hepatic portoenterostomy in two groups divided at the age of 60 days. Patients in the persistent jaundice group had greater expression of PCNA and TGF (21.7±16.0% and 76.9±20.7%, respectively) compared to those in the jaundice-free group (6.0±2.7% and 24.3±20.9%, P <0.001). PCNA and TGF expression in the bile-duct epithelium of the portal tract was closely related to prognosis in BA patients, and thus could be useful as a prognostic marker.  相似文献   
80.
Laparoscopic cholecystectomy in pregnancy   总被引:4,自引:1,他引:3  
Background: Laparoscopic cholecystectomy is now the standard treatment for symptomatic gallstones; while symptomatic gallstones during pregnancy are not frequent they are by no means rare. The role of laparoscopic cholecystectomy during pregnancy is controversial but initial reports suggest it is both safe and feasible. Methods: During a consecutive series of 500 laparoscopic cholecystectomies, 3 patients have undergone laparoscopic cholecystectomy during pregnancy. The 3 patients were 16–27 weeks pregnant with an average age of 32 years. The indication for laparoscopic cholecystectomy was severe pain in two patients and gallstone pancreatitis in one patient. Following standard obstetric anesthesia, laparoscopic cholecystectomy was performed. Open cannulation was used to establish peritoneal access, following which standard, four-port laparoscopic cholecystectomy was performed without complication. The insufflation pressure used was 8–10 mmHg CO2 and a liver retractor was employed to facilitate access. Results: In each case the postoperative recovery was rapid and uneventful for both mother and fetus. The patients were discharged on the first or second postoperative day. Conclusions: Laparoscopic cholecystectomy during the second trimester of pregnancy is both safe and feasible provided both suitable surgical and anesthetic expertise are available. Even up to the end of the second trimester there is sufficient access for the technique to be employed.  相似文献   
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