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101.
102.
103.
Aprotinin increases release of von Willebrand factor in cultured human umbilical vein endothelial cells. 总被引:1,自引:0,他引:1
M P Havel A Griesmacher G Weigel A Owen P Simon H Teufelsbauer T Vukovich E Wolner 《Surgery》1992,112(3):573-577
Through the perioperative administration of the proteinase inhibitor aprotinin, hemostasis can be improved and postoperative bleeding reduced after cardiac operations. The mechanism of action has been only partially clarified. The goal of our study was to investigate the influence of aprotinin on the synthesis of von Willebrand factor (vWF) in human endothelial cells. Human umbilical vein endothelial cells (HUVEC) were cultivated in vitro and incubated with different aprotinin concentrations (55, 100, and 215 mol/L). With all investigated aprotinin concentrations, there was an increase in vWF synthesis compared with basal secretion (p less than 0.001). When the HUVEC were preincubated with aprotinin and stimulated with thrombin, there was a further significant increase in vWF synthesis. HUVEC that, were first incubated with aprotinin and then stimulated with thrombin demonstrated a significant increase in vWF synthesis compared with basal secretion in nonincubated cells (p less than 0.0001). Also, compared with the cells that had received thrombin stimulation alone, the combination of aprotinin incubation and thrombin stimulation led to a significantly higher vWF concentration (p less than 0.05). Because vWF is necessary for the interaction with platelet factor glycoprotein Ib and platelet adhesion, the demonstrated increase in vWF synthesis could be one of the mechanisms of action of aprotinin leading to its blood-sparing effect. 相似文献
104.
105.
Carol Horrigan SRN RCNT Dip N PGCEA RNT MSc Complementary Therapies Adviser Lecturer Simon Mills MA FNIMH Projects Co-ordinator 《Complementary Therapies in Medicine》1994,2(4)
The rubric complementary medicine covers a variety of approaches that may seem alike only in their being outside conventional care and training. We have asked experienced practitioners to present their own pieces of this jigsaw, realising that these clinical fragments, when seen together, create excitement but also confusion. Of course, this forum is not intended to be a comprehensive review of relevant complementary treatments, and often the individual apporaches to clinical problems will appear totally unrelated, while their apparent effectiveness stretches the biomedical model and conventional research methodology beyond their capacity. With this in mind, we intend that forthcoming articles and reviews will expand on the therapies themselves, and discuss the evidence supporting them. 相似文献
106.
Use of stereotactic PET images in dosimetry planning of radiosurgery for brain tumors: clinical experience and proposed classification. 总被引:13,自引:0,他引:13
Marc Levivier Nicolas Massager David Wikler José Lorenzoni Salvador Ruiz Daniel Devriendt Philippe David Fran?oise Desmedt Stéphane Simon Paul Van Houtte Jacques Brotchi Serge Goldman 《Journal of nuclear medicine》2004,45(7):1146-1154
We developed a technique that allows the routine integration of PET in stereotactic neurosurgery, including radiosurgery. We report our clinical experience with the combined use of metabolic (i.e., PET) and anatomic (i.e., MRI and CT) images for the radiosurgical treatment of brain tumors. We propose a classification describing the relative role of the information provided by PET in this multimodality image-guided approach. METHODS: Between December 1999 and March 2003, 57 patients had stereotactic PET as part of their image acquisition for the planning of gamma knife radiosurgery. Together with stereotactic MRI and CT, stereotactic PET images were acquired on the same day using either (18)F-FDG or (11)C-methionine. PET images were imported in the planning software for the radiosurgery dosimetry, and the target volume was defined using the combined information of PET and MRI or CT. To analyze the specific contribution of the PET findings, we propose a classification that reflects the strategy used to define the target volume. RESULTS: The patients were offered radiosurgery with PET guidance when their tumor was ill-defined and we anticipated some limitation of target definition on MRI alone. This represents 10% of the radiosurgery procedures performed in our center during the same period of time. There were 40 primary brain lesions, 7 metastases, and 10 pituitary adenomas. Abnormal PET uptake was found in 62 of 72 targets (86%), and this information altered significantly the MRI-defined tumor in 43 targets (69%). CONCLUSION: The integration of PET in radiosurgery provides additional information that opens new perspectives for the optimization of the treatment of brain tumors. 相似文献
107.
Background
Late stage cancer malignancies may result in severe skeletal muscle wasting, fatigue and reduced quality of life. Resistance training may attenuate these derangements in cancer patients, but how this hypertrophic response relates to normal muscle adaptations in healthy subjects is unknown. Here, we determined the effect of resistance training on muscle mass and myosin heavy chain (MHC) isoform composition in plantaris muscles from tumor-bearing (TB) rats. 相似文献108.
Breathing can lead to organ motions up to several centimeters. For radiotherapy of lung, these motions are generally taken into account by adding a specific margin around the target. Thus, treated volumes are often too large to allow for the high-dose values requested for local control. To manage respiratory motion, deep-inspiration breath-hold technique (DIBH) and gated radiotherapy are starting being used clinically. DIBH consists in asking the patient to perform breath-hold during the treatment and the image acquisition, DIBH level being measured by a spirometer. Gated radiotherapy consists in treating the patient at a certain phase of the free breathing. Linac is synchronized with the motion of a marker located on the patient chest. Planning images are obtained by a four-dimensional CT (4D-CT) using the same marker. We have assessed the value of these two methods. For lung treatment, compared to a standard treatment, toxicity reduction was mainly due to the lung total volume increase. It is therefore more significant for breath-hold approach. It is also due to the reduction of safety margins, which is similar for both methods. These two techniques, which have specific advantages and drawbacks, are used routinely at Curie Institute for a large proportion of lung patients, but also for some breast, liver or even Hodgkin disease treatments. 相似文献
109.
Simon Y. K. Law F.R.C.S.Ed. Manson Fok F.R.C.S.Ed. John Wong Ph.D. 《World journal of surgery》1994,18(3):339-346
A study of risk factors that affect morbidity and mortality in 523 patients with squamous cell cancer of the esophagus who had one-stage resection was undertaken. The 30-day and hospital mortality rates were 5.0% and 15.5%, respectively. Pulmonary complications, malignant cachexia, and surgical complications accounted for 42%, 25%, and 21% of hospital deaths, respectively. Major pulmonary complications occurred in 23% of patients. Multivariate analysis identified six factors that predicted major pulmonary complications: age, mid-arm circumference, percent of predicted FEV1, abnormal chest radiograph, amount of blood loss, and palliative resection. Three risk groups of pulmonary complications were identified: low, median, and high risk group with complications in 3%, 17%, and 43% of patients, respectively. Significantly, patients with curative resection had a lower hospital mortality rate (9%) than those with palliative resection (20%), p=0.001. Patients with stage I, IIa, or IIb disease had a lower hospital mortality rate (9%) than those with stage III or IV disease (18%), p=0.026. Multivariate analysis identified six factors that predicted hospital death: age, mid-arm circumference, history of smoking, incentive spirometry, number of stairs climbed, and amount of blood loss. Three risk groups of hospital death were identified: low, median, and high risk groups with death in 7%, 30%, and 38%, respectively. Anastomotic leakage rate was 4%. Technical faults were identified in 53% of patients with leakage. Together with other surgical complications, a presumed or apparent technical error was noted in 63% of patients. The identification of high-risk patients and prevention of technical faults can help improve surgical outcome.
Resumen Se emprendió un estudio sobre los factores de riesgo que afectaron la mortalidad en 523 pacientes con carcinoma escamocelular del esófago sometidos a resección en una etapa en nuestra institución.Las tasas de mortalidad a 30 días y de mortalidad hospitalaria fueron 5% y 15%. Las complicaciones pulmonares, caquexia maligna y quirúrgica representaron 42%, 25% y 21% de las muertes hospitalarias, respectivamente. Complicaciones pulmonares mayores fueron registradas en 23% de los pacientes.El análisis multivariado identificó seis factores que predicen complicaciones pulmonares mayores: edad, circunferencia del brazo, porcentaje del FEV1 predecible, radiografía de tórax anormal, pérdida de sangre durante la operación y resección de tipo paliativo. Se identificaron tres grupos de riesgo de desarrollar complicaciones pulmonares: bajo, medio y alto, con tasas de 3%, 17% y 43% de los pacientes, respectivamente. Los pacientes que recibieron resección curative exhibieron una significativamente menor tasa de mortalidad hospitalaria (9%) en comparación con los que recibieron resección paliativa (20%), p=0.001. Los pacientes con enfermedad en estados I, IIa, IIb exhibieron menor mortalidad hospitalaria (9%) en comparación con los estados III o IV (18%), p=0.026. El análisis multivariado identificó seis factores que predicen mortalidad hospitalaria: edad, circunferencia del brazo, historia de tabaquismo, espirometría de incentivo, número de escalones que puede ascender y pérdida de sangre durante la operación. Se identificaron tres grupos de riesgo de mortalidad hospitalaria: bajo, medio y alto, con tasas de 7%, 30% y 38% respectivamente.La tasa de fuga anastomótica fue 4% y se identificaron defectos técnicos en 53% de los pacientes. Junto con otras complicaciones quirúrgicas, se observó un error técnico presumible o aparente en 63% de los pacientes.La identificación de los pacientes de alto riesgo y la prevención de los errores técnicos pueden ayudar a mejorar el pronóstico.
Résumé Dans cette étude, on a étudié les facteurs de risque influençant la morbidité et la mortalité chez 523 patients ayant un cancer épidermoïde de l'oesophage et ayant eu une résection en un seul temps. La mortalité à 30 jours et la mortalité hospitalière ont été respectivement de 5% et de 15.5%. Les complications pulmonaires, la cachexie maligne et les complications chirurgicales ont été responsable respectivement de 42%, 25% et 21% des décès hospitaliers. Une analyse multifactorielle a permis d'identifier six facteurs prédictifs des complications pulmonaires: l'âge, la circonférence brachiale, la prévision du volume expiratoire forcé en une seconde, les anomalies de la radiographie thoracique, la quantité de sang perdu, et le caractère palliatif de la résection. Trois groupes, dont le risque de complications pulmonaires a été classé faible, moyen et élevé, ont été identifiés. Le taux de complications dans ces groupes ont été respectivement de 3%, 17% et 43%. Les patients ayant eu une résection à visée curative avaient une mortalité hospitalière significativement plus basse (9%) comparée à celle des patients ayant eu une résection à visée palliative (20%) (p=0.001). Les patients ayant des maladies de stades I, IIa, IIb avaient une mortalité plus basse (9%) que ceux qui avaient des stades III ou IV (18%), (p=0.026). L'analyse multifactorielle a permis d'identifier six facteurs prédictifs de la mortalité hospitalière: l'âge, la circonférence brachial, des antécédents de consommation excessive du tabac, la spirométrie, le nombre d'escaliers que le patient peut monter, et la quantité de sang perdu. Trois groupes de patients, dont le risque de mortalité hospitalière a été classé faible, moyen, et élevé, ont eu des décès dans respectivement 7%, 30% et 38% des cas. Le taux de fistule a été de 4%. Une faute technique a été identifiée chez 53% des patients ayant eu une fistule. Une faute technique apparente ou présumée a été identifie chez 63% des patients ayant eu soit une fistule soit une complication chirurgicale. L'identification des patients à haut risque et la prévention des fautes techniques peuvent contribuer à améliorer le pronostic après chirurgie.相似文献
110.
The aim of this study was to carry out quantitative analyses of eye movements during the cover test on a group ( n = 57) of asymptomatic emmetropes. Eye movements were recorded during an automated cover test while subjects fixated a distance (3.4 m) and near (0.4 m) target. There was a significant difference between the amplitude of phoria measured after 2 s of occlusion compared to 10 s ( P < 0.01). The mean phoria after 10 s of occlusion was 0.1° (eso) for distance fixation and 1.6° (exo) for near fixation. The distribution was approximately normal for both distance and near fixation but the standard deviation was greater for near (2.0°) than distance fixation (1.4°). The pattern of eye movements during the recovery phase was more complex than is often assumed, in many cases consisting of a variety of saccadic and vergence movements involving both the covered and 'fixing' eye. The latency of the first recovery movement was significantly shorter for exophoric than esophoric deviations ( P < 0.01) and the latency of some recovery movements were very short (< 150 ms). 相似文献