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991.
EM Balén A Díez-Caballero JL Hernández-Lizoáin F Pardo JR Torramadé FM Regueira JA Cienfuegos 《Canadian Metallurgical Quarterly》1998,85(10):1415-1418
BACKGROUND: Operations for large and recurrent abdominal hernias have a high associated recurrence rate, although it is lower when prosthetic material is used. Expanded polytetrafluoroethylene (ePTFE) seems to be the best tolerated prosthetic material in surgery. METHODS: A series of 45 ventral hernias repaired using ePTFE for closure or reinforcement of the herniorrhaphy has been evaluated prospectively. Thirty-six were midline incisional hernias and nine were transverse or pararectal ventral hernias. There were 13 recurrent ventral hernias and three defects were operated as an emergency procedure. The patch was sutured to the anterior aponeurosis with a running non-absorbable suture. Some other kind of intra-abdominal procedure was undertaken in 12 cases. RESULTS: ePTFE was well tolerated. Complications occurred in five patients. Major complications were found in three patients: cutaneous necrosis requiring a myocutaneous flap; and infection of the prosthesis (primary, and secondary to enterocutaneous fistula due to diverticulitis, both requiring removal of the patch). Mean follow-up was 39 months and hernia recurrence occurred in only one patient. CONCLUSION: This clinical experience shows that ePTFE is a very reliable prosthetic material for the repair of abdominal wall hernias. 相似文献
992.
Participation in immune reactions of main morphological skin structures (epidermal cells, skin associated lymphoid tissue, macrophagal and vascular systems) is described. Cooperation of these systems in immune reaction by means of complementary receptors on the cell membranes, adhesive molecules, cytokines and lymphokines is discussed. Primary malignant skin lymphomas are considered as tumors of the skin immune system. 相似文献
993.
994.
Of 1,383 patients with carcinoma of the stomach seen at this institution during a 30 year interval, 37 were 35 years of age or younger. Fourteen of the patients were less than 30 years of age and the females predominated. While all young adults underwent roentgenologic examination of the upper gastrointestinal tract, only 12 had findings considered diagnostic for a malignant lesion of the stomach at the time of the initial study. Endoscopy with biopsy was done in 16 patients and confirmed the diagnosis of carcinoma in 13 patients. Carcinoma of the stomach was first diagnosed at laparotomy in 13 patients. Only 30 of 37 patients were considered operative candidates. Of the gastric resections done, 19 were curative and two, palliative. Seventy-six per cent of the lesions were either linitis plastica or poorly differentiated adenocarcinomas, and lymph node metastases were present in 31 patients. Prognosis was dismal. Thirty-one patients were dead within two years of diagnosis and only two patients have survived five years. In this series, carcinoma of the stomach in young people was particularly lethal. A high index of suggestive symptoms should prompt an early, aggressive roentgenologic and endoscopic evaluation of the upper gastrointestinal tract if any chance for an increase in cure rates is to be realized. 相似文献
995.
EM Pittel 《Canadian Metallurgical Quarterly》1998,37(10):1100-1102
BACKGROUND: Malignant melanoma is the most common metastatic tumor of the gastrointestinal tract and can present with abdominal pain, small bowel obstruction, or occult gastrointestinal bleeding. Diagnosing abdominal pain due to metastatic melanoma is best accomplished by intraluminal studies and computed tomography. Surgical resection of the tumor burden limited to the gastrointestinal tract has been shown to extend periods of palliation in this poor long-term survival group. OBJECTIVES: We will review a case of abdominal pain in a melanoma patient and review the literature. 相似文献
996.
RH Christenson SH Duh LK Newby EM Ohman RM Califf CB Granger S Peck KS Pieper PW Armstrong HA Katus EJ Topol 《Canadian Metallurgical Quarterly》1998,44(3):494-501
We compared cardiac troponins T (cTnT) and I (cTnI) collected within 3.5 h of ischemic symptoms for predicting clinical outcomes in 770 patients. cTnT (cutoff > 0.1 microgram/L) and cTnI (cutoff > 1.5 micrograms/L) were concordant (both positive or negative) in 90.4% of patients. Among discordant results, 66 were cTnT positive and cTnI negative vs 8 who showed the reverse (P < 0.001). Five cTnT-positive and cTnI-negative patients died within 30 days; none who were cTnT negative and cTnI positive died. cTnT showed a slightly greater association (chi 2 = 18.0, P < 0.001) with 30-day mortality than cTnI (chi 2 = 12.5, P = 0.002). The area of the ROC curve for predicting 30-day mortality was significantly larger (Z = 2.08; P = 0.0375) for cTnT, at 0.68 [95% confidence interval (CI) 0.60-0.75], compared with cTnI, at 0.64 (95% CI 0.56-0.72). When cTnI and the electrocardiogram (ECG) were put in a logistic multiple regression model, cTnT added significant information (chi 2 = 8.03, P = 0.045); however, cTnI did not add to a model containing cTnT and the ECG (chi 2 = 0.84, P = 0.657). cTnT provided more information than cTnI for predicting 30-day mortality early after presentation with acute coronary syndromes. 相似文献
997.
S Moscarella G Buzzelli RG Romanelli M Monti C Giannini G Careccia EM Marrocchi AL Zignego 《Canadian Metallurgical Quarterly》1998,18(5):366-369
The prevalence of Helicobacter pylori (HP) IgG antibodies was analysed in a group of 142 asymptomatic children (group A) and in 31 pediatric patients (group B) with recurrent abdominal pain. HP IgG antibodies were measured by a commercially available fluorescence-enzyme immuno-assay test (Heloritest IgG, Fa Eurospital). In asymptomatic children the prevalence of HP IgG antibodies increased significantly with age from 17% with 6 years to more then 40% with 14 years. A higher prevalence of HP IgG antibodies was found in children living in more crowded housing conditions. Comparing the number of HP IgG positive children in group B (58%) to a matched population from group A (35%) no statistically different prevalence rates were found. Thus HP IgG antibodies are found in similar frequencies, in both, symptomatic and asymptomatic children. Therefore the presence of HP-IgG antibodies does not necessarily indicate that the HP infection is the cause for the recurrent abdominal pain in these children. 相似文献
998.
B Seitz L Moreira E Baktanian D Sanchez B Gray EM Gordon WF Anderson PJ McDonnell 《Canadian Metallurgical Quarterly》1998,126(5):630-639
PURPOSE: To determine the potential of somatic gene transfer as a technique for modulating corneal wound healing after superficial keratectomy. METHODS: The transduction of human and rabbit keratocytes with beta-galactosidase and herpes simplex virus thymidine kinase genes was performed. In vitro, human and rabbit keratocytes were transduced with retroviral vectors bearing beta-galactosidase or HStk (herpes simplex virus thymidine kinase) genes. In vivo, rabbit keratocytes were transduced by topical application of vector supernatant after a superficial keratectomy. In vitro and in vivo, expression of the beta-galactosidase gene was examined with histochemical staining. In vitro, ganciclovir cytotoxicity in HStk gene-transduced keratocytes and bystander effect in co-cultures of HStk(+) and HStk(-) keratocytes were measured by determining the degree of confluency of cells in 6-well plates after 10 days of incubation. Corneal haze in rabbits was measured after transduction with Hstk and subsequent treatment with topical ganciclovir. RESULTS: In vitro, both human and rabbit keratocytes were transduced successfully with both beta-galactosidase and HStk genes. Transduction efficiency was greater with human (22%) than with rabbit (16%) cells, and both HStk-transduced cell lines showed dose-dependent ganciclovir cytotoxicity and a significant bystander effect. In vivo, expression of beta-galactosidase within vimentin-positive corneal stromal cells confirmed transduction of keratocytes in the rabbit after superficial stromal keratectomy with an efficiency of 25% to 40%. Postoperative application of topical ganciclovir reduced corneal stromal haze in rabbits. CONCLUSIONS: The ability to genetically transduce stromal keratocytes provides a new strategy for understanding the important cellular and molecular events that influence corneal wound healing, thus offering a potential approach to decrease or prevent corneal haze and scarring after superficial keratectomy. 相似文献
999.
1000.
EM Anderman 《Canadian Metallurgical Quarterly》1998,31(2):128-138
A recombinant Fv construct of the B1 monoclonal antibody that recognizes the LewisY-related carbohydrate epitope on human carcinoma cells has been prepared. The Fv is composed of the polypeptide chains of the VH and VL domains expressed independently and isolated as inclusion bodies. The Fv is prepared by combining and refolding equimolar amounts of guanidine chloride solubilized inclusion bodies. The Fv is stabilized by an engineered interchain disulfide bridge between residues VL100 and VH44. This construct has a similar binding affinity as that of the single-chain construct (Benhar and Pastan, Clin. Cancer Res. 1:1023-1029, 1995). The B1 disulfide-stabilized Fv (BldsFv) crystallizes in space group P6(1)22 with the unit cell parameters a = b = 80.1 A, and c = 138.1 A. The crystal structure of the BldsFv has been determined at 2.1-A resolution using the molecular replacement technique. The final structure has a crystallographic R-value of 0.187 with a root mean square deviation in bond distance of 0.014 A and in bond angle of 2.74 degrees. Comparisons of the BldsFv structure with known structures of Fv regions of other immunoglobulin fragments shows closely related secondary and tertiary structures. The antigen combining site of BldsFv is a deep depression 10-A wide and 17-A long with the walls of the depression composed of residues, many of which are tyrosines, from complementarity determining regions L1, L3, H1, H2, and H3. Model building studies indicate that the LewisY tetrasaccharide, Fuc-Gal-Nag-Fuc, can be accommodated in the antigen combining site in a manner consistent with the epitope predicted in earlier biochemical studies (Pastan, Lovelace, Gallo, Rutherford, Magnani, and Willingham, Cancer Res. 51:3781-3787, 1991). Thus, the engineered disulfide bridge appears to cause little, if any, distortion in the Fv structure, making it an effective substitute for the B1 Fab. 相似文献