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61.
A previous report from the authors' institution reported the effectiveness of hepatic packing with absorbable fine mesh (AFMP) for the control of hemorrhage in an animal model with an otherwise lethal hepatic injury. The technique has subsequently been applied to 12 abdominal trauma patients with hemodynamic instability and actively hemorrhaging hepatic injuries. Two patients expired in the operating room owing to uncontrolled hemorrhage from hepatic and associated injuries for a mortality of 16.7%. AFMP was successful in controlling hemorrhage in the remaining 10 patients. Hepatic injuries ranged from grade II to grade V, and all were actively hemorrhaging at the time of exploration. None of the surviving 10 patients experienced early or late recurrent bleeding attributable to the hepatic injuries, and there were no intraabdominal abscesses or late deaths. Liver function studies returned to normal prior to discharge in all surviving patients. Follow-up included serial computed tomographic scans, which demonstrated fibrosis incorporating the mesh packing. Complete resolution of injury and mesh appears to proceed over approximately a 6-month period. AFMP is a safe, effective method for controlling hepatic hemorrhage. It is easy to perform in the operating room, offers an excellent matrix for hemostasis, provides tamponade of bleeding sites, and does not require reoperation for removal of packing material, as is necessary with conventional, nonabsorbable packing techniques.
Resumen En una publicación previa se informó la eficacia del empaquetamiento hepático con una fina malla absorbible en el control de la hemorragia en un modelo animal experimental sometido a lesión hepática letal. Desde entonces la técnica ha sido aplicada en 12 pacientes con trauma abdominal e inestabilidad hemodinámica y lesiones hepáticas sangrantes. Dos pacientes expiraron en la mesa de operaciones por hemorragia no controlada proveniente de la arteria hepática y de otras lesiones asociadas, con una tasa de mortalidad de 16.7%. La malla fue eficaz en cuanto a controlar la hemorragia en el resto de los pacientes. Las lesiones hepáticas variaron en cuanto a severidad entre los Grados II a V y todas exhibían hemorragia activa en el momento de la exploración. Ninguno de los 10 sobrevivientes desarrolló sangrado recurrente temprano o tardío que pudiera ser atribuible a las lesiones hepáticas y no se observaron abscesos intraabdominales o muertes tardías. Las pruebas de función hepática retornaron a valores normales con anterioridad al egreso, en la totalidad de los sobrevivientes. El seguimiento incluyó tomografías computadorizadas seriadas, que demostraron fibrosis del área de empaquetamiento con la malla; la resolución completa de la lesión y de la malla parece tener lugar en el curso de seis meses, aproximadamente. La malla representa un método seguro y eficaz de control de la hemorragia hepática, es fácil de aplicar en el quirófano, ofrece una excelente matriz para la hemostasia, produce taponamiento de los sitos sangrantes y no requiere reoperación para remover el material de empaquetamiento, como sí lo requieren las técnicas convencionales de empaquetamiento con materiales no absorbibles.

Résumé Nous avons déjà rapporté l'efficacité du packing périhépatique par un filet fin résorbable (FFA) pour contrôler l'hémorragic autrement mortelle provenant d'une lésion hépatique chez l'animal. Cette même technique a été utilisée utilisée chez 12 patients ayant un traumatisme sévère du foie avec une hémodynamique instable. Deux patients sont décédés en salle d'opération des lésions hépatiques et des structures avoisinantes soit une mortalité de 16.7%. La technique de FFA a été couronnée de succès chez les 10 autres patients. Les lésions ont été classées selon leur sévérité du grade II au grade V et toutes saignaient activement au moment de l'opération. Aueun des patients survivants n'a eu de récidive hémorragique attribuable à la lésion hépatique et il n'y a eu aucun abcès intra-abdominal ni de mortalité tardive. La fonction hépatique est redevenue normale avant la sortie chez tous les autres patients. La surveillance du suivi a comporté une tomodensitométrie montrant une fibrose autour du filet. La résolution complète de la lésion et la résorption du filet évoluent en général sur six mois. La technique de FFA est sûre et efficace dans le contrôle de l'hémoragie provenant des traumatismes du foie. La méthode est facile à appliquer en salle d'opération, procure une hémostase excellent par tamponnade et ne nécessite pas de réintervention pour enlever le packing comme quand on utilise le matériel traditionnel non résorbable.
  相似文献   
62.
An X-ray fluorescence (XRF) technique using plane polarized X-rays for excitation was used for in vivo measurements of cadmium in the kidney cortex among non-occupationally exposed members of the general population in southern Sweden. The measured concentrations of cadmium in the kidney cortex of smokers (median 28 g/g, n = 10) were significantly higher (P = 0.0036) as compared to those in non-smokers (median 8 g/g, n = 10), and so were the cadmium concentrations in blood and urine. The results show that smoking considerably increases the cadmium concentration in the kidney cortex and that smoking is a major source of cadmium exposure in the general population of Sweden. Except in the presence of very deeply situated kidneys, where the minimum detectable concentration is high, non-invasive in vivo XRF analysis of kidney cadmium should be a useful tool for evaluating the effects of long-term low-level exposure to cadmium and the risk of kidney damage.  相似文献   
63.
The metabolism of pentachlorophenol has been studied in the rat after pretreatments with phenobarbital, 3-methyl-cholanthrene or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). In addition to the previously identified metabolite, tetrachloro-p-hydroquinone, trichloro-p-hydroquinone has been identified in urine as a metabolite. The formation of the latter represents a type of dechlorination different from that of the formation of tetrachlorohydroquinone. The inducing agents, 3-methylcholanthrene and TCDD have similar effects on the dechlorination and increase the formation of tetrachloro-p-hydroquinone more pronounced than does phenobarbital. In contrast to phenobarbital they also increase the formation of trichloro-p-hydroquinone and the total elimination of pentachlorophenol and its metabolites. The in vivo findings are supported by in vitro studies with microsomes from rats pretreated with phenobarbital or TCDD. Use of the inhibitor -diethylaminoethyl-diphenyl propylacetate (SKF 525-A) in vitro showed a more pronounced inhibition on microsomes from phenobarbital-treated rats than on microsomes from untreated or TCDD-treated rats.Gas chromatography-mass spectrometry have been used for the identification and quantification of pentachlorophenol and its metabolites.
Zusammenfassung Der Metabolismus von Pentachlorphenol nach Vorbehandlung der Versuchstiere (Ratten) mit phenobarbital, 3-Methylcholantren oder 2,3,7,8-Tetrachlordibenzo-p-Dioxin (TCDD) ist untersucht worden. Zu dem schon früher nachgewiesenen Metaboliten Tetrachlor-p-Hydrochinon wurde nun auch Trichlor-p-Hydrochinon als Harnmetabolit festgestellt. Die Bildung des letzteren stellt eine andere Art von Dechlorierung dar als diejenige die bei der Entstehung von Tetrachlor-p-Hydrochinon vorliegt. 3-Methylcholantren und TCDD haben ähnlichen Einfluß auf die Dechlorierung und steigern die Bildung von Tetrachlor-p-Hydrochinon mehr ausgeprägt als es bei phenobarbital der Fall ist. Im Gegensatz zu phenobarbital steigern sie auch die Bildung von Tri-chlor-p-Hydrochinon sowie die totale Eliminierung von Pentachlorphenol und von Metaboliten. Die in vivo-Befunde werden von in vitro-Studien mit Mikrosomen von mit phenobarbital oder TCDD vorbehandelten Ratten gestützt. Anwendung des Inhibitors -Diethylaminoethyl-Diphenyl-Propylacetat (SKF 525-A) zeigte in vitro eine ausgeprägtere Inhibition der Mikrosomen von mit phenobarbital behandelten Ratten als der Mikrosomen von unbehandelten oder TCDD-behandelten Ratten. Nachweis und Bestimmung von Pentachlorphenol und seinen Metaboliten wurden gaschromatographisch-massenspektrometrisch durchgeführt.
  相似文献   
64.
Rats were treated chronically with -methyl-p-tyrosine methyl-ester HCl (-MT) twice daily for 0–14 days. At 1 h after the (last) -MT injection, d-amphetamine sulphate was given and motor activity was measured in an ANIMEX activity meter for 4 h. Amphetamine-induced excitatory and stereotyped behaviour was scored according to a rating scale in a separate experiment. A single dose of -MT markedly reduced the activity response after amphetamine. After 1–3 days of -MT treatment, tolerance to its amphetamine-antagonistic affect started to develop, reaching a maximal degree after 7–14 days. The pattern of the amphetamine response, monophasic in control rats, became biphasic in the -MT tolerant rats with an early (at 0–1 h) and a late (2–4 h) peak of motor activity. The late peak appeared within 3 days, while the early peak appeared after 7 days of -MT treatment. The results on amphetamine-induced excitatory and stereotyped behaviour in essence agreed with the motor-activity data. It is concluded that tolerance to the amphetamine-antagonistic action of -MT is not complete. Its rate of development varies in a complex pattern, indicating the presence of more than one mechanism of tolerance.  相似文献   
65.
Following systemic administration of the noradrenaline (NA) neurotoxin, DSP4 (50 mg/kg), rats were found to be retarded in the rate at which they acquired the "right-turn" running response in a modified T-maze choice situation, as measured by the total number of errors per session and median latency to reach the goal box. Desipramine (DMI, 20 mg/kg), injected 30 min before DSP4 blocked the acquisition retardation. DSP4 was found to have a short-lasting effect upon spontaneous motor activity, while food and water intake recovery was complete within 7 days of the injection. Both the NA-accumulation data and endogenous NA concentrations indicated profound NA, but not 5-hydroxytryptamine (5-HT) and dopamine (DA), depletions in the cortex, hippocampus and cerebellum. These data seem to confirm the role of the locus coeruleus-noradrenaline (LC-NA) system in an instrumental learning situation.  相似文献   
66.
In our surgical clinic, from January 1, 1978, to May 15, 1982, a total of 41 patients with polytrauma exhibited 45 concomitant vascular injuries requiring operation. This group of patients represents 10% of the 407 multiple trauma patients treated during this period. The incidence of vascular lesions of shoulder, neck, and upper extremities was 2.7% (n=11); lower extremities, 4.7% (n=19); within the abdominal cavity, 1% (n=4); and of acute thoracic aortic rupture, 2.7% (n=11). Seven patients (17%) died: 4 from additional brain trauma, 3 from hemorrhage by aortic ruptures. There were 6 major amputations (2 primary, 4 secondary) and 2 borderline amputations. In the remaining 26 patients, a good result following vascular repair was achieved. Angiologic examination, including computed tomography and angiography, is of great importance. Vascular repair deserves high priority since bleeding and/or ischemia threatens the patient's limbs, organs, or even life. This is especially true for the acute thoracic aortic rupture as a typical vascular injury in polytrauma. The incidence of peripheral vascular injuries in polytrauma is twice as high (7.3%) as in isolated extremity fractures (3.6%).  相似文献   
67.
Summary Leukemic cells from patients presenting with acute nonlymphoblastic leukemia and normal hematopoietic bone marrow cells from healthy donors for allogeneic bone marrow transplantation were incubated for 3 h with doxorubicin and epirubicin at different concentrations. The intracellular uptake at the end of the incubation was determined by photofluorometry in leukemic cells from 15 patients and in normal cells from 9 donors for bone marrow transplantation. Cytotoxicity in vitro against granulocyte/macrophage colony-forming units (CFU-GM) was determined in normal cells from 7 donors, and in vitro toxicity against leukemic cells was determined by a clonogenic technique in cells from 6 patients and by vital dye staining (DiSC) following 4 days' culture in cells from 15 patients. Epirubicin was significantly less toxic than doxorubicin to normal hematopoetic cells (72%±20% survival of cells for epirubicin vs 45%±13% for doxorubicin at a concentration of 0.2 m;P0.005). As analyzed by the DiSC assay, 0.2 m epirubicin was slightly more toxic to leukemic cells than was the same concentration of doxorubicin (47% vs 61% survival,P0.01), but the clonogenic assay revealed no difference in toxicity to leukemic cells. At a concentration of 0.2 m, the mean intracellular uptake of epirubicin in leukemic cells was 0.43±0.26 nmol/mg protein as compared with 0.33±0.14 nmol/mg protein for doxorubicin (not significant). In normal cells, the uptake of epirubicin at a concentration of 0.2 m was 0.47±0.25 nmol/mg protein as compared with 0.31±0.21 nmol/mg protein for doxorubicin (not significant). The reduced myelotoxicity observed in vitro together with the retained toxicity to leukemic cells indicates that the therapeutic index of epirubicin is better than that of doxorubicin.  相似文献   
68.
Method for Dissection of Mesenteric Metastases in Mid-gut Carcinoid Tumors   总被引:1,自引:0,他引:1  
With adequate medical management the midgut carcinoid tumor generally is an indolent malignancy associated with substantial life expectancy and appreciable life quality, even in the presence of liver metastases and significant tumor burden. Abdominal complications may occur in this entity of carcinoids owing to entrapment of intestines and encasement of mesenteric vessels by mesenteric metastases and associated marked mesenteric fibrosis. This may be the cause of abdominal pain, disabling diarrhea, weight loss to the extent of malnutrition, and eventually the risk of death with acute or chronic intestinal obstruction or intestinal gangrene. Operative removal of the mesentericointestinal lesion is often indicated to prevent or treat these complications but may be technically difficult when mesenteric metastases extend in the vicinity of major vessels in the mesenteric root. At laparotomy 56 patients with advanced midgut carcinoids underwent removal of the mesenteric tumor with a method for preserving the mesenteric vessels. This was feasible by mobilizing and releasing the right colon and mesenteric root from posterior adhesions, identifying the mesenteric artery below the pancreas, and free-dissecting this artery on the tumor capsule in the mobilized mesentery. Dissection was successful even with tumors initially judged inoperable unless tumor growth completely surrounded the mesenteric vessels or extended retroperitoneally. One patient was subjected to distal intestinal artery bypass. Symptom relief was been substantial and often of long duration after mesenteric tumor removal in patients who prior to surgery often had threatening intestinal ischemia. Patients with advanced midgut carcinoids may benefit markedly from dissectional removal of mesenteric tumors, which (conceivably better than conventional wedge resection) preserves the length of the remaining intestine.  相似文献   
69.
PURPOSE: To evaluate treatment outcome of 3D conformal high dose rate (HDR) brachytherapy and external beam irradiation (EBRT) combined with temporary androgen deprivation for patients with localized prostate cancer. PATIENTS AND METHODS: Between January 1997 and September 1999 we treated 102 patients with stage T1-3 N0 M0 prostate cancer. Stage T1-2 was found in 71, T3 in 31 patients. Median pretreatment PSA level was 15.3 ng/ml. After ultrasound-guided transrectal implantation of four afterloading needles, CT based 3D brachytherapy planning was performed. All patients received four HDR implants using a reference dose per implant of 5 or 7Gy. Time between each implant was 14 days. After brachytherapy EBRT followed up to 39.6 or 45.0 Gy. All patients received temporary androgen deprivation, starting 2-19 months before brachytherapy, ending 3 months after EBRT. RESULTS: Median follow-up was 2.6 years (range 2.0-4.1 years). Actuarial biochemical control rate was 87% at 2 years and 82% at 3 years. In 14 patients we noted biochemical failure, in five patients clinical failure. Overall survival was 90%, disease specific survival 98.0% at 3 years. Acute grade 3 toxicity occurred in 4%, late grade 3 toxicity in 5%. One patient developed a prostatourethral-rectal fistula as late grade 4 toxicity. The conformal quality of 300 HDR implants was analyzed using dose volume histograms. CONCLUSIONS: 3D conformal HDR brachytherapy and EBRT combined with temporary androgen deprivation is an effective treatment modality for prostate cancer with minimal associated toxicity and encouraging biochemical control rates after a median follow-up of 2.6 years.  相似文献   
70.
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