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991.
Background: Biliopancreatic diversion (BPD), by ad hoc stomach resection (AHS-BPD) has been accepted as an effective surgical treatment for morbid obesity. Methods: Between 1.1.1992 and 31.7.1996, 59 patients (54 females, five males, mean age 40.3 years, range 23-61 years) underwent AHS-BPD. Mean preoperative body-weight was 121.2 kg (range 94-160), with a mean body mass index of 48.6 (range 35-64). Three of these patients were converted from a previous vertical banded gastroplasty to AHS-BPD (one patient with stomach preservation). After at least 36 months follow-up, seven patients underwent abdominal dermolipectomy (five with associated incisional hernia repair, one with thigh dermolipectomy). Results: Mean post-operative hospital stay was 13 days (range 10-30 days). Follow-up is currently in progress in all patients. Excess body weight-loss was 78% in 33 patients with 24 months follow-up, with excellent long-term weight loss maintenance. Protein deficiency was the main specific complication, encountered in two patients (3.4%). Mortality was one patient (1.7%), due to pulmonary embolus. Conclusions: This clinical experience supports the effectiveness and safety of AHS-BPD, despite some criticism. This procedure appears to be suitable for patients with clinically severe obesity who will poorly tolerate food intake restriction but will accept long-term follow-up. Careful preoperative clinical assessment and selection of patients who will be reliable in long-term follow-up are the keys to success with AHS-BPD, both in terms of weight loss and reduction of specific metabolic complications.  相似文献   
992.
993.
Determination of polyamines (putrescine, spermidine and spermine) in urine samples of patients was worked out using high performance liquid chromatography (HPLC) and pre-column derivatization. For HPLC separation, a method of reversed-phase chromatography with gradient elution of water-organic mobile phases, UV and fluorescence detection were applied. Special care was devoted to the preseparation step, the hydrolysis, derivatization and selective extraction of clinical samples. The optimal HPLC conditions were recommended for simultaneous determination of putrescine, spermidine and spermine in a minimal analysis time (about 15 min) and suitable chromatographic resolution values (Rij greater than 1.5). Detection limits for all polyamines were evaluated (40 pmol for putrescine, 25 pmol for spermidine and 20 pmol for spermine) for the analysis of polyamines in the urine. The urine samples of healthy people and the cancer patients were compared and the procedure or the complete analysis has been described.  相似文献   
994.
995.
There are several indications that central nervous system (CNS) lesions in visna are immune-mediated and that cell-mediated immunity (CMI) may be of importance in the initiation of the lesions. To study the role of CMI in the pathogenesis of CNS lesions, five sheep were infected by intracerebral inoculation with visna virus and observed for 1 year. The following parameters were monitored at regular intervals: (1) neutralizing and ELISA antibodies; (2) visna virus-specific stimulation of lymphocytes from peripheral blood; (3) lymphocyte subpopulations in peripheral blood, cerebrospinal fluid (CSF) and brain at sacrifice. The CNS lesions were graded and compared with other parameters. The time course and titers of antibodies did not correlate with the severity of CNS lesions whereas the CMI did, indicating that CMI may play an important role in lesion development. The correlation of the number of CD8-positive cells in the CSF with the severity of lesions and the reversed ratio of CD4/CD8-positive cells in the diffusely infiltrated neuroparenchyma indicates that the CD8-positive T lymphocyte may be an important effector cell in the induction of CNS lesions.  相似文献   
996.
997.
998.
Following the pioneering work of Ross and Barratt-Boyes, there is currently a strong evidence based on long-term follow-up data that valve homografts are the best valve substitutes in the aortic position. Currently there exists a renewed interest in the use of fresh and cryopreserved homografts as we know that homografts show a prolonged durability together with the lack of thromboembolic complications. Here we present the case histories of 3 patients undergoing aortic valve replacement by fresh homografts sterilized in antibiotic solution. The underlying pathology was infective endocarditis in all 3 patients, a disease that is considered the ideal indication for homograft implantation. Technical details at the time of implantation, their advantages with regard to other replacements devices and the whole process of procurement, manipulation and preservation are commented on.  相似文献   
999.
1000.
Authors report on the possibilities of the operative treatment of the corpus scapulae. In chosen cases--young patients, isolated occurrence, great dislocation--they have performed the plate osteosynthesis of the corpus fractures. The frequency of the occurrence, the classification of fractures, the possibilities of the operative technique, the indication of the operations, the postoperative therapy are mentioned and their cases are described.  相似文献   
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