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101.
Anastomosis   总被引:6,自引:1,他引:5  
Esophageal anastomosis is still associated with a high rate of complications even though they have decreased considerably in recent years. Anastomotic leaks are more frequent in the neck than in the chest, and related mortality rate is not different. The leakage incidence does not depend on suture materials or on technical modalities used to perform the anastomosis. In fact, there is no difference between the leakage rate when comparing manual and mechanical anastomoses. The leak incidence after both mechanical and manual anastomoses is much higher in collective reviews than in reports coming from leading centers. Frequent esophageal surgeons can learn from their previous experience and therefore avoid technical errors, whereas casual esophageal surgeons do not have this opportunity. Performing an esophageal anastomosis is a technical matter, and suture healing is independent of the patient's biologic situation. Anastomotic fibrotic stricutures are frequent after both manual and mechanical anastomoses, and most can be avoided by meticulous suturing technique.
Resumen La anastomosis esofágica todavía se asocia con una elevada incidencia de complicaciones, a pesar de que éstas han descendido en forma considerable en los últimos años. Las fugas anastomóticas son más frecuentes en el cuello que en el tórax y las tasas de mortalidad no son diferentes. La rata de fuga anastomótica no depende de los materiales de sutura o de las modalidades técnicas que se utilicen para realizar la anastomosis. De hecho no hay diferencia en cuanto a la rata de fugas entre las anastomosis manuales y las mecánicas. La incidencia de fuga, tanto en las manuales como en las mecánicas, es bastante más alta en las revisiones colectivas que en los reportes emanados de los centros médicos de mayor importancia. Los cirujanos especialistas en esófago tienen la posibilidad de aprender de sus experiencias previas y con ello evitar los errores técnicos, en tanto que aquellos cirujanos ocasionales no la poseen. La realización de una anastomosis esofágica es un asunto técnico y la cicatrización de la sutura es independiente de la condición biológica del paciente. Las estrecheces fibróticas de las anastomosis son frecuentes luego de las anastomosis manuales, al igual que luego de las anastomosis mecánicas y la mayoría puede ser evitada mediante una técnica meticulosa.

Résumé Le taux de complications des anastomoses oesophagiennes, même s'il y en a moins ces dernières années, reste toujours élevé. La fréquence de fistules est plus grande quand l'anastomose est faite au cou par rapport au thorax, mais la mortalité n'en est pas très différente. L'incidence de fistules ne dépend ni du matériau de suture ni des modalités d'anastomoses utilisées. Il n'y a aucune différence lorsque les anastomoses manuelles sont comparées aux anastomoses méchaniques: L'incidence des fistules, que ce soit à la main ou à la machine est plus élevée dans les séries collectives par rapport à celle des centres spécialisés. Les chirurgiens qui font des anastomoses de façon régulière ont la possibilité de profiter de leur expérience et ainsi d'éviter les erreurs techniques, alors que le chirurgien occasionnel de l'oesophage n'a pas cette possibilité. L'anastomose oesophagienne est techniquement difficile et la cicatrisation est indépendante de l'état clinique et biologique du patient. Les sténoses fibreuses sont aussi fréquentes après les anastomoses manuelles qu'après les anastomoses méchaniques, mais la plupart peuvent être évitées par une technique méticuleuse.
  相似文献   
102.
Objectives In this case-control study we tested the hypothesis of an association between some psychosomatic skin diseases, attachment style and stress. Patients and methods A total of 177 cases and 194 controls seen between November 1992 and November 1993 at the Istituto Dermopatico dell'lmmacolata (IDD) in Rome, were enrolled into the study. Cases were outpatients with first diagnosis of hyperidrosis, chronic urticaria, generalized pruritus or alopecia areata. Controls were outpatients seen in the same period of time with first diagnosis of pigmenled nevi, keratosis or mycosis. The presence and weight of life stress events were assessed by u standard precoded questionnaire based on the Schedule of Recent Experiences (SRE) and on the Life Experiences Survey (LES). The attachment style was assessed by a modified version of the Shaver and Hazan questionnaire about feelings in a love relationship. We calculated 3 scores for each individual and classified study subjects in 2 groups: 1) "free" (= secure attachment); 2) "not free" (not secure attachment: anxious-ambivalent or avoidant). Questionnaires were self-administered in the presence of a trained psychologist. Adjusted odds ratios (OR) were calculated using a multiple logistic function. Results No association was found between the different stress scores and the skin diseases considered. The crude odds ratio for life stress events in the previous year was 1.4 (95% CI 0.8–2.7). After multiple adjustment for age, sex, marital status and education, the estimated OR was 1.6 (95% CI 0.8–3.0). One significant association emerged between the adult attachment style defined as “not free” and psychosomatic skin diseases: the adjusted OR was 4.0 (95% CI 1.4–12).  相似文献   
103.
A male infant, born from consanguineous parents, suffered from birth with a progressive neuromuscular disorder characterized by psychomotor delay, hypotonia, muscle weakness and wasting, deep-tendon areflexia and spastic posture. High levels of lactic acid in blood and cerebrospinal fluid suggested a mitochondrial respiratory chain defect. Muscle biopsy revealed raggedred and cytochromec oxidase-negative fibres, lipid accumulation and dystrophic changes. Multiple defects of respiratory complexes were detected in muscle homogenate, but cultured fibroblasts, myoblasts and myotubes were normal. Southern blot analysis showed markedly reduced levels of mitochondrial DNA (mtDNA) in muscle, while lymphocytes, fibroblasts and muscle precursor cells were normal. Neither depletion of mtDNA nor abnormalities of the respiratory complexes were observed in innervated muscle fibres cultured for as long as 4 months. No mutations were observed in two candidate nuclear genes,mtTFA andmtSSB, retro-transcribed, amplified and sequenced from the proband's mRNA. Sequence analysis of the mtDNA D-loop and of the origin of replication of the mtDNA light strand failed to identify potentially pathogenic mutations of these replicative elements in the proband's muscle mtDNA. Our findings indicate that mtDNA depletion is due to a nuclear encoded gene and suggest that the abnormality underlying defective mtDNA propagation must occur after muscle differentiation in vivo.  相似文献   
104.
We have analysed the [AGC] expansion in leucocytes, muscle and sperm from 17 individuals affected by myotonic dystrophy (DM). Skeletal muscle showed a larger repeat number than leucocytes in the same patient. A similar degree of expansion was detected in differently affected muscles of a single patient. The germline mutation ( 350 repeats) was expanded in somatic cells of the progeny in all patients examined. Our results provide evidence of an early postzygotic instability of the [AGC] repeat in DM.  相似文献   
105.
Immunological changes among workers occupationally exposed to styrene   总被引:2,自引:0,他引:2  
The functional status of the immune system was investigated in a group of 71 workers exposed to styrene and in 65 control subjects, recruited according to the same selection criteria and comparable as to sex, age, and confounding variables. Air and biological monitoring were used to characterize styrene exposure (median of the main urinary metabolites in the next-morning spot samples: 106 mg/g creatinine). Phenotypic analysis of peripheral blood lymphocytes (PBL) by automated flow cytometry revealed a reduced proportion of T lymphocyte subsets (CD3+, CD4+ and CD4+45+), with no changes in CD8+, and a higher proportion of B lymphocytes (CD19+) among styrene-exposed workers. The exposed workers showed a higher proportion of activation markers, namely DR and interleukin-2 receptors (CD25). Immunoglobulin subclasses were comparable in the two groups. An increased prevalence of abnormally low values was apparent for CD2+, CD3+, CD4+, CD4+45+ and CD11b subsets among workers exposed to styrene, whereas CD19+, DR+ and CD25+ showed an increased prevalence of abnormally high values. Natural killer-related phenotypes (CD56+, CD56+16+, and CD56+16) were more expressed among styrene workers, with average increase of 30%. However, the frequency distribution of the lytic activity of natural killer cells against K-562 target cells was shifted towards lower values in the exposed workers as compared to control subjects. Dose-response relationships between indices of internal dose and prevalence of abnormal values were detectable for T lymphocyte subsets, NK phenotypes, and activation markers. These findings suggest that moderate exposure to styrene is associated with an altered distribution of lymphocyte subsets. The decreased proportion of T lymphocytes, mainly of T helper-inducer cells, could hamper regulatory functions, thus suggesting a negative modulation by styrene exposure. Since a proper balance between immunocycte subsets is important for immunological responses, such changes should be regarded as adverse effects.  相似文献   
106.
Familial neuroblastoma occurs rarely. We studied a family with three children; one of them has a disseminated (stage 4) and another has a localized (stage 2) neuroblastoma. We observed subtelomeric locus D1Z2 (1p36) deletion in both tumors by using double-color fluorescence in situ hybridization. The MYNC gene was found in single copy in both tumors. Loss of heterozygosity (LOH) and restriction fragment length polymorphism analyses were performed by using DNA from frozen tumor cells and from microdissected tumor areas excised from paraffin-embedded sections. We detected somatic LOH at locus D1S468 (1p36) in a tumor-cell population with a trisomy 1 of the stage-2 patient. Neuroblastoma cells of the stage-4 patient were diploid and showed allelic loss at the following loci: D1S172, D1S80, D1S94, D1S243, D1S468, D1S214, D1S241, and D1S164. Haplotype study showed that the siblings inherited the same paternal 1p36-->pter chromosome region by homologous recombination and that, in the two tumors, arm 1p of different chromosomes of maternal origin was damaged. Our results suggest that the siblings inherited the predisposition to neuroblastoma associated with paternal 1p36 region and that tumors developed as a consequence of somatic loss of the maternal 1p36 allele.  相似文献   
107.
(Received for publication on Apr. 28, 1997; accepted on May 15, 1998)  相似文献   
108.
Occupational exposure to high concentrations of anesthetic gases (more than 500 ppm of nitrous oxide and more than 15 ppm of halothane and enflurane) can cause neurobehavioral effects in operating room personnel. Factors such as stress and work organization play an additional role in reducing performance capacities. It is still unclear whether these conditions may become the predominant factor in behavioral impairment when exposure to anesthetic gases is reduced; in addition, we wished to ascertain the extent of neurobehavioral and neuroendocrine effects at relatively low levels of exposure to such gases. Therefore the same group of 30 operating room personnel was examined with neurobehavioral tests during gaseous and nongaseous anesthesia. In this way, the neuropsychological performance was examined under the same stress conditions, but with different exposure levels to anesthetic gases. Serum cortisol was measured as an additional biological stress indicator. Prolactin secretion was examined to study possible interference of anesthetic gases with the dopaminergic system. The results were compared with those in a control group of 20 hospital workers from other departments, with similar characteristics in respect of age, sex, and education. During work with gaseous anesthesia, average airborne concentrations (geometric mean) of nitrous oxide were 50.9 ppm (SD 20.8) on the first day of the working week and 54.2 ppm (SD 22.1) on the last day of the working week, whereas average urinary nitrous oxide (geometric mean) were 21.54 g/l on the first day of the working week and 25.67 g/l on the last day of the working week. The operating room workers showed slower reaction times at the end of the week with gaseous anesthesia, compared with workers using nongaseous anesthesia and the control group. At the same time they also showed increased secretion of prolactin, whereas cortisol remained unchanged. Therefore, it can be concluded that lower levels of exposure to anesthetic gases (and not only high exposure levels) cause an impairment of neurobehavioral performance, with the action of stress being less relevant. The mechanism of anesthetics' neurotoxic action seems to be related to interference with the dopaminergic system.  相似文献   
109.
A new method for intraperitoneal tumour targetting in ovarian cancer using biotinylated monoclonal antibodies (MoAb) and radioactive streptavidin is described. Fifteen patients with histologically documented ovarian carcinoma were injected intraperitoneally with 2 mg of biotinylated MoAb MOv18, followed 3–5 days later by 100–150 g of indium-111 streptavidin, at the specific activity of 280–370 MBq/mg in 500 ml of normal saline. No toxicity was observed. Tumours were imaged from 2 to 48 h after radioactivity injection by recording both planar and single photon emission tomography (SPET) data. All patients underwent surgery 1–8 days later (mean 3 days) after scanning. The resected tumour and normal tissue radioactivity were measured. On the day of surgery, the tumour to normal tissue ratio was 9:1 (range 3:1–30:1) and 45:1 (range 12:1–120:1) for intra- and extraperitoneal samples, respectively. The mean tumor to blood ratio was 14:1 (range 4:1–30:1). The injected dose (i.d.) per gram of tumour was 0.112 (range 0.01–0.3) for recurrences and 0.05 for primary tumour (range 0.005–0.2). Over 24–48 h 14% i.d. (range 8–18% i.d.) was found in the urine, 14% i.d. (range 629% i.d.) in the blood and 63% i.d. (range 56–70% i.d.) was still in the peritoneal cavity. These preliminary clinical data suggest that this two-step strategy may be superior to the conventional approach (radiolabelled antibodies) for intraperitoneal radioimmunolocalization and radioimmunotherapy of ovarian cancer. Offprint requests to: G. Paganelli  相似文献   
110.
Seventy-eight patients with cirrhosis were prospectively followed for up to 20 months, on the average. At entry into the study, galactose elimination capacity, aminopyrine breath test, and ICG clearance were measured. At the end of the study, 27 patients had died. Univariate analysis using the Kaplan-Meier method showed that both quantitative liver function tests (galactose elimination capacity:P<0.025; aminopyrine breath test:P<0.001; ICG clearance:P<0.005) and common clinical and biochemical data (encephalopathy:P<0.001; ascites:P<0.001; serum bilirubin:P<0.005; serum albumin:P<0.001; prothrombin index:P<0.05) were significant predictors of survival. To investigate whether quantitative liver function tests could contribute to a better definition of the prognosis, once Pugh score had already been taken into account, a multiple regression analysis according to the Cox model was performed. Pugh score and galactose elimination capacity resulted in the only independent prognostic covariates. From them a prognostic index was calculated, and the model was validated in an additional sample of 70 patients investigated according to the same protocol. The contribution GEC gave to the assessment of overall prognosis over that obtained using the Pugh score was slight, as estimated by the statistical parameters of the Cox's model, but was significant as assessed by a ROC curve analysis (P=0.05). These data show that all quantitative liver function tests were predictors of survival in cirrhosis, and that the galactose elimination capacity added some new prognostic information to those already available using the Child-Turcotte-Pugh classification.This study was supported in part by a grant from the Italian Ministry of Education (National Project Liver Cirrhosis). Part of this study was presented at the 22nd Meeting of the European Society for Clinical Investigation, Graz, Austria, April 20–23, 1988.  相似文献   
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