Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Zeitschrift für angewandte Mathematik und Physik 43 (1992), S. 567-580 
    ISSN: 1420-9039
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Physics
    Notes: Abstract Several inverse design methods using conformai mapping in 2-D have been developed, which, however, do not permit an extension in 3-D. The present 2-D inverse design method involves a linearized system resulting from small perturbations of a 2-D direct calculation procedure. The feasibility of this method is demonstrated by examples taken from industrial applications. The principles involved make possible an extension in 3-D.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-2323
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Les tentatives associant la chirurgie à la radiothérapie pour traiter les malades opérables atteints de cancer de l'oesophage datent de 30 ans. Les premières séries chirurgicales rapportées firent état d'un faible taux de résécabilité et d'un taux élevé de mortalité opératoire. Les résultats à long terme de la radiothérapie isolée furent également décevants en particulier chez les sujets à bon risque chirurgical et porteurs de petite tumeur. L'option en faveur d'un traitement mixte reposa sur le fait que la radiothérapie pouvait entrainer une réduction de l'activité tumorale et de la masse tumorale, une amélioration de l'état nutritif grâce à la possibilité de déglutition, une réduction de la greffe de la tumeur, et un effet sur la maladie régionale périoesophagienne qui n'est guère accessible au traitement chirurgical. D'autre part, la chirurgie permettait souvent une résection étendue, l'élimination de foyers résiduels et l'exérèse de l'extension intra-murale du processus tumoral. En fait, les limites de la méthode combinée sont représentées par la toxicité de l'irradiation préopératoire. Elle doit être suffisamment modérée pour que la chirurgie puisse être entreprise sans retard excessif et sans risque d'augmentation du taux de la mortalité. De nombreuses modalités radio-thérapeutiques ont été employées en ayant recours à des champs, des doses, des fractionements différents mais ces modalités n'ont pas donné lieu à des études randomisées. Les résultats finaux d'un troisième essai prospectif conduit par l'organisme E.O.R.T.C. sont présentés.
    Abstract: Resumen Los intentos de combinar radioterapia con cirugía en casos operables de carcinoma de esófago se iniciaron hace 30 años. Las primeras series quirúrgicas reportadas mostraron un bajo índice de resectabilidad y una elevada mortalidad post-operatoria. Los resultados de la radioterapia sola también fueron decepcionantes a largo plazo, especialmente en pacientes que aparecían como de excelente riesgo operatorio con tumores pequeños y localizados. La razón para un enfoque combinado era que la radioterapia podría reducir el tamaño y actividad del tumor, lograr una mejoría del estado nutricional al restablecer la capacidad de deglución, disminuir la “trasplantabilidad” del tumor, y obtener un efecto curativo sobre la enfermedad regional periesofágica que no es susceptible de adecuado tratamiento con la cirugía. Por otro lado, la cirugía con frecuencia permitía una resección ampliada, con lo cual se limpian focos residuales o extensión distal en la pared esofágica. El límite del enfoque combinado es la toxicidad de la irradiación preoperatoria, la cual debe ser lo suficientemente leve como para permitir realizar la cirugía sin excesiva demora ni incremento en la mortalidad operatoria. Numerosos programas de radioterapia fueron utilizados sobre diferentes campos y con diversas dosis y fraccionamientos, la mayoría en estudios no aleatorizados. Dos estudios prospectivos y aleatorizados han sido informados recientemente. Los resultados finales de un tercer ensayo prospectivo, bajo la EORTC (Organización Europea para la Investigación y el Tratamiento del Cáncer), son presentados.
    Notes: Abstract Attempts to combine radiation therapy and surgery in patients with operable carcinoma of the esophagus began 30 years ago. The first reported surgical series showed a low rate of resectability and a high postoperative mortality. Results of radiation therapy alone were also disappointing in the long run, especially in patients who appeared to be excellent operative risks with small localized tumors. The rationale for a combined approach was that x-ray therapy could bring about a reduction of tumor activity and bulk, an improvement in nutritional state through the restoration of the ability to swallow, a reduction of transplantability of the tumor, and a curative effect on periesophageal regional disease which is not treated well by surgery. On the other hand, surgery often allowed an extended resection, clearing residual foci or distant esophageal wall extension. The limit of a combined approach is the toxicity of the preoperative radiation which must be mild enough to allow surgery to proceed without excessive delay or increased mortality. Numerous radiotherapy schedules were tried using different fields, doses, and fractionations, most of them in nonrandomized studies. Two prospective randomized trials have been recently reported. The final results of a third prospective trial, run by the E.O.R.T.C., will be presented.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1615-5947
    Keywords: Peripheral occlusive vascular disease ; below-knee amputation ; open-stump technique
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Between January 1, 1985, and December 31, 1988, we prospectively studied the outcome of 62 consecutive below-knee amputations with primary closure in 56 patients. There were 35 men and 21 women; mean age was 70 years. Above-knee amputation was performed for occlusion of the profunda femoris artery, acute thrombosis of a popliteal aneurysm with inadequate sural artery vascularity, intractable knee flexion contracture, suspended ischemia, and occasionally, when ischemia was found intraoperatively to extend proximally during below-knee amputation. Bedridden patients deemed unfit for prosthetic devices were also candidates for above-knee amputation. Fifty-four lower extremities (87%) were gangrenous and rest pain was present in eight patients (13%). Twenty-nine limbs (47%) were amputated primarily, 33 (53%) after failure of one or more revascularization procedures. Six patients had bilateral amputation. Forty patients (71%) were diabetic. Mean hospital stay was five days. Fifteen patients (27%) died during a mean follow-up period of 29 months. Eleven stumps (17.5%) required reoperation: five for postoperative infection, four for wound breakdown after a fall, and two for secondary abscess. Three secondary above-knee amputations (5%) were necessary. Of 44 below-knee amputations in diabetic patients, one had to be revised at the level of the thigh. Of 33 amputations after revascularization failure, one secondary above-knee amputation was necessary. Restoration of preischemic status was achieved after a mean of 58 days. Upon patient discharge from a rehabilitation center, 44 stumps (81%) were suitable to be fitted with prostheses. Compared with the open-stump technique, primary closure of below-knee amputation stumps reduces healing time without an increased reoperation rate. Hospitalization is short and reestablishment of patient autonomy is rapid.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1615-5947
    Keywords: Renal artery ; fibromuscular dysplasia ; aneurysms ; renovascular hypertension ; ex vivo repair ; autotransplantation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Between November 1980 and July 1989, 29 ex vivo reconstructions were performed in 12 women and five men (mean age: 42 years) for dysplastic lesions of renal artery branches. Fifteen patients had hypertension, associated with advanced renal failure in one case. The internal iliac artery was used routinely for reconstruction. The saphenous vein was used on one side where bilateral repairs were necessary. A total of 52 distal anastomoses were performed, an average of 2.6 per revascularized kidney. Mean follow-up was four years and 10 months. No patients were lost to follow-up. There were no early or late deaths. At least one follow-up arteriogram and technetium99 diethylene triamine pentacetic acid scintiscan was obtained for all patients. Forty-five (86%) of 52 anastomoses remained patent. Eleven of 15 hypertensive patients completely recovered while four were improved. Systolic arterial blood pressure decreased by an average of 42 mmHg (p 〈 0.001), and results remained stable with time. For fibromuscular dysplasia occurring in young patients whose life expectancy is usually long, this type of surgery provides excellent long-term clinical and anatomical results.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Annals of vascular surgery 6 (1992), S. 294-297 
    ISSN: 1615-5947
    Keywords: Lower limb ischemia ; pulmonary embolism ; homocystinuria ; oral contraceptives
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Homocystinuria was discovered in a 21-year-old woman when she presented with lower limb ischemia and pulmonary embolism. This patient had a partial deficit in cystathionine-synthetase and took strongly dosed oral contraceptive medication. This report underscores: (1) the value of searching for this type of pathology even in the adult; (2) the possibility of disclosure by another condition, and particularly, drug-induced; (3) the importance of searching for other involved members of the same family; and (4) the possibility of treatment in vitamin sensitive patients.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1615-5947
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The use of arterial or venous allografts for vascular reconstruction was first reported in 1951, but long-term results have been disappointing. Rejection and inappropriate methods of preservation are the main reasons for failure. A successful solution to this problem could be achieved by programmed cryopreservation with cryoprotectant. Our study had two aims: to define the biomechanical properties of cryopreserved arterial allografts and to study their histologic appearance. Arteries were removed as part of a protocol for multiorgan harveting for transplantation. Cryopreservation was performed within the first 24 hours after harvesting. Programmed cryopreservation with 15% dimethyl sulfoxide (cryoprotectant) was used. Mechanical testing was done immediately after thawing. Two groups were tested: a control group of fresh aortas and a group of cryopreserved aortas. Axial and circumferential strips were tested. High strain modulus and stress and strain characteristics were calculated for each strip. There was no statistically significant difference between the mechanical properties of fresh and cryopreserved human descending thoracic aortas. Biochemical tests were performed in the preservative solution at 1 and 7 days in both groups. There was no statistically significant difference between the two groups at day 1 or day 7 (p 〉 0.05). Histologic studies before and after arterial cryopreservation included standard and electron microscopy and showed that arteries had normal structure after cryopreservation. These results confirm that programmed cryopreservation with cryoprotectant does not alter the molecular or geometric configuration of collagen or elastic fibers. Endothelial cells were still present; however, their viability and function were not assessed. The results of our studies have encouraged us to use cryopreserved arterial allografts for clinical application, and to date 27 patients have received cryopreserved arterial allografts. Definitive results including histologic and immunologic findings will be reported in the future when the length of follow-up is adequate.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Annals of vascular surgery 8 (1994), S. 421-426 
    ISSN: 1615-5947
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The records of 52 patients aged 80 years or older who underwent 56 carotid artery reconstructions were analyzed retrospectively. Four patients had amaurosis fugax, 27 patients had experienced one or more transient ischemic attacks, eight had a completely or partially reversible stroke, and 10 had vertebrobasilar insufficiency. Three patients were asymptomatic. Arteriograms documented stenosis 〉80% on the operated side in 48 cases, whereas the contralateral carotid artery was occluded or had 〉80% stenosis in 10 cases each. Two or more cerebral arteries were involved in 37 patients. CT scans were normal in only 21 (40%) patients. General anesthesia was used in 54 of 56 operations. Thirty-six endarterectomies, 18 bypasses, and two resection-anastomoses (for tortuosity) were performed. A shunt was employed in eight (14.3%) cases. One lethal stroke (1.9%) occurred during the first postoperative month. Three patients experienced nonfatal strokes, two of which gave rise to residual deficits. Two patients were lost to follow-up. For the remaining 49 patients the mean follow-up was 24 months. Two-year actuarial survival was 76.3% for the entire series and 67% for those surviving without neurologic events. This study shows that when properly selected the elderly population can safely undergo carotid surgery.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1615-5947
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The purpose of this study was to evaluate the benefits of collagen-impregnated Dacron grafts in patients undergoing infrarenal aortic reconstruction. We therefore prospectively compared two consecutive series of patients undergoing infrarenal aortic reconstruction with Dacron grafts between January 1991 and December 1992. The first group (group A) included 83 high-density knitted prosthetic grafts (Dialine I), whereas the second included 82 grafts of the same type but impregnated with collagen (Dialine II). The two groups were comparable with regard to age, sex, and operative risk factors. They were also comparable in terms of the proportion of patients with occlusive disease or aneurysms, that is, there were 39 and 36 patients with occlusive disease and 44 and 46 patients with aneurysms in groups A and B, respectively. The type of bypass was similar in both groups with 17 and 19 tubular grafts and 66 and 63 bifurcated grafts being inserted in groups A and B, respectively. Thirteen parameters were studied and compared within each group including (1) number of infected grafts, (2) number of postoperative occlusions, (3) maximum postoperative temperature, (4) number of positive postoperative blood cultures, (5) number of postoperative deaths, (6) intraoperative and (7) postoperative quantities of blood transfused, (8) difference between pre- and postoperative hemoglobin concentrations, (9) difference between pre- and postoperative fibrinogen levels, (10) difference between pre- and postoperative platelet counts, (11) duration of aortic clamping,(12) date of return of intestinal function, and (13) mean duration of pre- and postoperative hospital stays. One death, one graft occlusion, and one postoperative infection were observed in group A, whereas there were three deaths, two occlusions, and one postoperative infection in group B (difference not significant). Of all the parameters studied, the only significant difference concerned the reduction in transfusion requirements of units when a collagen-impregnated graft was inserted (p〈0.05). These results are similar to those observed with other standard or collagen-coated knitted grafts. Less loss of blood, resulting in a reduced theoretic risk of viral contamination, appears to be the main advantage of collagen-coated grafts.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1615-5947
    Keywords: Palmar arteries ; bypass ; hand surgery ; digital ischemia ; peripheral vascular disease
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract This study reports the late results of eight palmar bypass procedures performed between 1983 and 1988 in eight men patients with a mean age of 43 years old, who presented with unilateral digital trophic disorders. The origin of the arterial lesions was post-traumatic in four cases, embolic in three cases, and aneurysmal in one. The procedures performed included four radiopalmar bypasses, two ulnar-palmar bypasses, one distal radial bypass and one palmopalmar bypass. In all cases, the replacement conduit used was the superficial radial vein retrieved from the wrist. There were no complications observed in this short series. All fingers healed within three weeks' time after excision of necrotic lesions. During a mean follow-up of 66 months, two bypasses became thrombosed, leading to amputation of the distal phalanx of a thumb in one patient while the remaining six bypasses remained patent, three of them for more than seven years. In the presence of trophic changes of the fingers, palmar arch bypasses, whenever feasible, are more effective at long-term and less aggressive than the usually proposed thoracic sympathectomy.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1573-2568
    Keywords: colitis cystica profunda ; enteritis cystica profunda ; solitary rectal ulcer syndrome ; enterocolitis ; inflammatory bowel disease
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Enteritis cystica profunda and diffuse colitis cystica profunda are exceedingly rare conditions. We report here the first case in which these two entities are associated in one patient. This 48-year-old woman presented initially with a solitary ulcer of the rectum and developed later deep ileal and colonic ulcerations with intervening normal mucosa, polypoid masses, and a dense fibrosis of the bowel wall. Colon and ileum specimens demonstrated submucosal mucous cysts and occasionally herniation of mucosal epithelium into the submucosa, which led to the diagnosis of enteritis and colitis cystica profunda. The exact nature of the underlying ileocolonic disease, which necessitated colectomy and extensive ileal resection, remained undetermined although an aggravating role of iterative surgical procedures is possible. Enteritis cystica profunda and diffuse colitis cystica profunda therefore seem to share a common pathogeny and have to be considered as lesions complicating an underlying disease rather than specific and autonomic diseases.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...