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81.
82.
Concentrations of plasma fibrinopeptide A (FPA) were measured by radioimmunoassay in 50 patients with venous thromboembolism or disseminated intravascular coagulation or both. A consistent discrepancy was observed in values obtained with two anti-FPA antisera. Analysis of extracts from plasma of these patients by high-performance liquid chromatography (HPLC) revealed the presence of a phosphorylated and an unphosphorylated form of the A peptide. Differences in concentrations of FPA measured with the two antisera could be accounted for by their different reactivity with phosphorylated FPA (FPA-P). The differences were abolished by treatment with alkaline phosphatase. A good correlation was observed between the FPA-P content of free A- peptide material and of fibrinogen in plasma as determined by HPLC (r = .88, P less than .001, n = 11). In patients with elevated FPA levels, the mean FPA-P content of fibrinogen was significantly higher (P less than .002, n = 13) than in patients with normal FPA levels (n = 8) and in healthy controls (n = 14). Phosphorus in fibrinogen did not correlate with fibrinogen degradation products or fibrinogen levels and became normal on adequate anticoagulation. Therefore, blood-clotting activation may lead to a high phosphate content of fibrinogen and of free FPA in plasma.  相似文献   
83.
OBJECTIVE: The open Nissen fundoplication is effective therapy for gastroesophageal reflux disease. In this study, the outcomes in 198 patients treated with the laparoscopic Nissen fundoplication was evaluated for up to 32 months after surgery to ascertain whether similar positive results could be obtained. SUMMARY BACKGROUND DATA: To ensure surgical success, patients were required to have mechanically defective sphincters on manometry and increased esophageal acid exposure on 24-hour pH monitoring. The patients either had severe complications of gastroesophageal reflux disease or had failed medical therapy. These requirements have been found to be necessary to ensure a successful surgical outcome. METHODS: The disease was complicated by ulceration (46), stricture (25) and Barrett's esophagus (33). Patients underwent standard Nissen fundoplications identical in every detail to open procedures except that the procedures were carried out by the laparoscopic route. RESULTS: Perioperative complications included gastric or esophageal perforation (3), pneumothorax (2), bleeding (2), breakdown of crural repair (2) and periesophageal abscess (1). The only mortality occurred from a duodenal perforation. Six patients required conversion to the open procedure. The median hospital stay was 3 days. One hundred patients were observed for follow-up for 6 to 32 months (median 12 months), with outcomes similar to the open Nissen fundoplication. Further surgery was required for two patients who had recurrent gastroesophageal reflux and one who developed an esophageal stricture. Ninety-seven percent are satisfied with their decision to have the operation. CONCLUSIONS: The laparoscopic Nissen fundoplication can be carried out safely and effectively with similar positive results to the open procedure and with all of the advantages of the minimally invasive approach.  相似文献   
84.
OBJECTIVE: The authors provide an assessment of mechanisms leading to hernia recurrence after laparoscopic and traditional preperitoneal herniorrhaphy to allow surgeons using either technique to achieve better results. SUMMARY BACKGROUND DATA: The laparoscopic and traditional preperitoneal approaches to hernia repair are analogous in principle and outcome and have experienced a similar evolution over different time frames. The recurrence rate after preperitoneal herniorrhaphy should be low (< 2%) to be considered a viable alternative to the most successful methods of conventional herniorrhaphy. METHODS: Experienced surgeons supply specifics regarding the mechanisms of recurrence and technical measures to avoid hernia recurrence when using the preperitoneal prosthetic repair. Videotapes of laparoscopic herniorrhaphy in 13 patients who subsequently experienced a recurrence also are used to determine technical causes of recurrence. RESULTS: Factors leading to recurrence include surgeon inexperience, inadequate dissection, insufficient prosthesis size, insufficient prosthesis overlap of hernia defects, improper fixation, prosthesis folding or twisting, missed hernias, or mesh lifting secondary to hematoma formation. CONCLUSIONS: The predominant factor in successful preperitoneal hernia repair is adequate dissection with complete exposure and coverage of all potential groin hernia sites. Hematoma mesh lifting and inadequate lateral inferior and medial inferior mesh fixation represent the most common causes of recurrence for surgeons experienced in traditional or laparoscopic preperitoneal hernia repair.  相似文献   
85.
86.
The surgical management results of recurrent hiatal hernia repair are unknown in the laparoscopic era. The experience of the senior authors (CJF) and (SKM) is reported herein. From 1993 to 2004, 52 patients underwent re-operative hiatal hernia surgery at our center. Preoperative symptoms were heartburn, chest pain, dysphagia, regurgitation and pulmonary manifestations of gastroesophageal reflux disease. Patients had preoperative evaluation by upper endoscopy, pH-monitoring, esophagogram and manometry to assess the mechanism of failure. Pre- and postoperative symptoms were assessed utilizing a standardized questionnaire. Patients underwent laparoscopic repair (n=18), open laparotomy (n=6) and transthoracic surgery (n=28). Ninety-five percent follow-up was achieved with a mean follow-up of 34 months. Thirty-seven percent of patients encountered para-operative complications one of them died due to respiratory insufficiency. Five patients experienced a re-recurrent hernia. The symptom resolution was 65% for dysphagia, 68% for heartburn, 95% for chest pain and 79% for regurgitation. The overall patient satisfaction was 6.94 on a scale of 1–10. There was no significant difference in patient outcome when comparing the operative approaches or disease process. Surgical repair of recurrent hiatal hernias is safe and effective. Laparoscopic surgery is an appropriate alternative approach for recurrent hiatal hernia repair in selected patients.  相似文献   
87.
Spinal malignancies are an essential consideration when a patient presents to a chiropractic office with back pain. This single case report exemplifies the importance of patient presentation and physical examination findings. We must also consider the rationale for x-raying patients on an individual case basis. Textbook cases do not always exist and special diagnostic tests do not always provide a definitive diagnosis of underlying pathology. Even though history and examination findings suggest a routine diagnosis, continual re-evaluation and recognition of the need to change the diagnosis on occasion is extremely important. The patient should not only be thoroughly evaluated upon initial presentation, but also each time they present for treatment. The decision to x-ray a patient is considered important. X-ray examination can be used to confirm a diagnosis or to rule out potential pathologies, and not necessarily done as a routine screening procedure.A case report is presented in which the pathologic signs were not evident on plain film x-rays upon initial presentation.  相似文献   
88.
Purpose: To retrospectively examine the optic disc photographs of a glaucoma population for optic disc haemorrhages, vascular occlusions and vascular abnormalities. Methods: The optic disc photographs of 906 eyes of glaucoma and suspect glaucoma patients were examined. Optic disc photographs were taken annually, where possible, with the follow-up period varying between 1 and 14 years duration (mean, 2.89). Glaucoma patients are regularly reviewed every 4–6 months and glaucoma suspects every 1–2 years, depending on the ophthalmologist. Low-tension glaucoma patients were reviewed more frequently (mean, every 2.6 months). The results of the findings were compared to a control group of 39 subjects with a mean follow-up period of 7 years, using Fisher's exact test. Results: It was found that during the period under review, 7.4% (n= 67) of eyes had optic disc haemorrhages. The highest frequency of optic disc haemorrhages (37.5%) was found in the low tension glaucoma group (P= 0.0001) followed by 11.4% of primary open-angle glaucoma eyes (P= 0.03). In the normal group there were three eyes with optic disc haemorrhages and one with a disc collateral, which constitutes 5.1% vascular changes in this sub-group. Of the study eyes 2.8% had central retinal vein occlusions, 1.3% branch vein occlusion, 1.2% disc vessel abnormalities (loops) and 1.1% disc collaterals. Discrete nerve fibre layer haemorrhages and microaneurysms were found in 0.8% and 1.8% of eyes, respectively. Conclusions: A total of 16.8% of the eyes observed in this study had either disc haemorrhages or vascular changes. The underlying trend of vascular and haemorrhagic changes in glaucoma are demonstrated in this sample, which is in general agreement with previous studies. The high percentage of optic disc haemorrhages in low tension glaucoma is highlighted. The presence of microaneurysms and nerve fibre layer haemorrhages is interesting but of unknown significance.  相似文献   
89.
The solution conformation of a cyclic RGD peptide analogue, cyclo-(S,S)-2-merrcaptobenzoate-arginine-glycine-aspartate -2-mercaptoanilide, has been determined via two independent approaches for the searching of conformational space and identification of conformations consistent with NMR and CD spectroscopic data: (i) the use of a binary genetic algorithm and (ii) a molecular dynamics simulation. Inter-proton distances were obtained via analysis of cross-peak volumes from a two-dimensional ROESY NMR spectroscopy experiment at 600 MHz and were used as constraints for the computational calculations. The mercaptoanilide amide proton resonance chemical shift had a very small temperature coefficient, indicating that this proton was hydrogen-bonded. Circular diehroism data showed that, in solution, the torsion angle about the disulfide bond was negative, consistent with one of the distinct conformations around this bond in the 200 ps molecular dynamics simulation. The backbone conformations of the structures resulting from the two different approaches were very similar.  相似文献   
90.
Open laparoscopy for laparoscopic cholecystectomy.   总被引:2,自引:0,他引:2  
This report deals with the first 350 laparoscopic cholecystectomies performed at Creighton University, beginning in October 1989, by one of the authors (R.J.F., Jr.). An open technique was used for initial access to the abdominal cavity in 343 patients (98%). Patients included 274 females and 76 males, with an average age of 45.5 years. Weight ranged from 72 to 316 pounds (32-142.2 kg). The laparoscopic procedure was successfully completed in 338 (96.6%). Operative cholangiography was performed in 113 (32.3%), and 52 (14.7%) had acute cholecystitis as determined by the final pathological report. Median operating time was 80 min. There was no operative mortality. Bile duct injury was not seen. Postoperative complications occurred in 21 patients (6%), only two of which were directly related to the open technique (cellulitis of the umbilical wound requiring antibiotics). A third patient (0.3% of 343 successful laparoscopies) required reoperation on postoperative day 4 for a small bowel perforation; the exact cause could not be determined, but conceivably it was related to the umbilical minilaparotomy. We conclude that the open technique is safe and effective method for initial peritoneal access prior to laparoscopic cholecystectomy.  相似文献   
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