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21.
Marta Méndez-López Magdalena Méndez Fernando Sánchez-Patán Isabel Casado Maria-Angeles Aller Laudino López Maria-Teresa Corcuera Maria-Jose Alonso Maria-Paz Nava Jaime Arias Jorge-Luis Arias 《Journal of gastrointestinal surgery》2007,11(2):187-194
To obtain a new model of chronic portal hypertension in the rat, two classical methods to produce portal hypertension, partial portal vein ligation and the oral administration of thioacetamide (TAA), have been combined. Male Wistar rats were divided into four groups: 1 (control; n?=?10), 2 [triple partial portal vein ligation (TPVL); n?=?9], 3 (TAA; n?=?11), and 4 (TPVL plus TAA; n?=?9). After 3 months, portal pressure, types of portosystemic collateral circulation, laboratory hepatic function tests (aspartate aminotransferase, alanine aminotransferase, bilirubin, alkaline phosphatase, and gamma-glutamyl transpeptidase) and liver histology were studied. The animals belonging to group 2 (TPVL) developed extrahepatic portosystemic collateral circulation, associated with mesenteric venous vasculopathy without hepatic destructurization or portal hypertension. Animals from group 3 (TAA) developed cirrhosis and portal hypertension but not extrahepatic portosystemic collateral circulation, or mesenteric venous vasculopathy. Finally, the animals from group 4 (TPVL?+?TAA) developed cirrhosis, portal hypertension, portosystemic collateral circulation, and mesenteric venous vasculopathy. The association of TPVL and TAA can be used to obtain a model of chronic portal hypertension in the rat that includes all the alterations that patients with hepatic cirrhosis usually have. This could, therefore, prove to be a useful tool to study the pathophysiological mechanisms involved in these alterations. 相似文献
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23.
Carlos Ferrer Albiach Antonio Conde Moreno Marta Rodríguez Cordón Virginia Morillo Macías Ana Bouché Babiloni Inmaculada Beato Tortajada Ángel Sánchez Iglesias Alicia Francés Muñoz 《Clinical & translational oncology》2010,12(1):22-26
Hypoxia is related to poor prognosis because it is associated to chemo-and radioresistance. During recent years the evolution
of imaging methods like PET/CT and MRI has meant the appearance of new perspectives with direct implications in radiation
therapy. We discuss previous experiences in staging, planning and in the follow-up process with these techniques for measuring
tumour hypoxia. 相似文献
24.
Krzysztof Kociski Marta Krenz‐Niedbaa Agnieszka Kozowska‐Rajewicz 《American journal of human biology》2004,16(1):31-42
This study investigated a hypothesis of dependence of child height and weight on the month of their birth. The sample comprised 1,241 subjects, 568 boys and 673 girls, age 6–20 years, from villages in Olsztyn Province, Northeast Poland. Individuals' height and weight data were standardized by sex and age to allow grouping of individuals born in the same month irrespective of their sex and age at examination. Subjects born in October to March proved to be significantly taller and heavier than those born in April to September. The magnitude of differences between the semiannual groupings equaled 13.1% of a standard deviation (SD) in height (P = 0.03) and 14.2% of SD in weight (P = 0.02). The month‐of‐birth effect was much stronger for children characterized by high socioeconomic status, where these differences amounted to 39.1% of SD in height (P = 0.02) and 49.4% of SD in weight (P = 0.01). There were no regular changes of the effect with age and no differences between the sexes were found. Fitted cosine functions identified the highest values of examined traits for individuals born in December with the lowest values being found in those born in June. Possible explanations of the month‐of‐birth effect are considered in terms of age categorizing, seasonal variety of growth rates, as well as birth‐related or conception‐related global, hemispheric, and local factors. This study rejects the first two possibilities and suggests this effect requires further research to be conducted in various geographical locations, climates, and cultures, on humans as well as on other species. Am. J. Hum. Biol. 16:31–42, 2004. © 2003 Wiley‐Liss, Inc. 相似文献
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Gy?rgy Lang Attila Cseke? Georgios Stamatis Ludwig Lampl Leif Hagman Gabriel Mihai Marta Michael Rolf Mueller Walter Klepetko 《European journal of cardio-thoracic surgery》2004,25(2):160-166
OBJECTIVES: Persisting air leakage after pulmonary resection remains a significant problem. The aim of the study was to evaluate the incidence of air leakage after standard lobectomy and test the efficacy and safety of TachoComb (TC). METHODS: A total of 189 patients undergoing lobectomy were enrolled in a multi-centre, open, randomised, and prospective study to test the efficacy and safety of TachoComb (TC) for air leakage treatment. Air leakage was assessed by water submersion test, and scored as grades 0 if no, 1 if countable, 2 if a stream of and 3 if coalescent bubbles have been observed. Any sites with grade 3 air leakage received further stapling or limited suturing until grade 0, 1 or 2 was obtained. Treatment of air leakage was done with TC or suturing according to randomisation. Air leakage was assessed by further submersion tests. Postoperative air leakage was assessed using the Pleur-Evac system. RESULTS: Overall incidence of air leakage 48+/-6 h after surgery was 34% for TC and 37% for standard treatment (P=0.76). The reduction of intra-operative air leak intensity in the subgroup with grades 1-2 was significantly higher for the TC group (P=0.015). Postoperative air leakage intensity in the subgroup with air leakage grades 1-2 was lower for TC than standard treatment (P=0.047). The mean duration of postoperative air leakage in the subgroup with grades 1-2 was shorter for the TC group than for standard treatment, i.e. 1.9+/-1.4 vs. 2.7+/-2.2 days (P=0.015). CONCLUSIONS: TC could be proven as well-tolerated and safe. In the subgroup of patients with established air leakage, TC showed superior potential in reduction of intra-operative air leakage as well as in reduction of intensity and duration of postoperative air leakage. 相似文献
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Roberto Rivera-Luna Marta Zapata-Tarrés Aurora Medina-Sansón Enrique López-Aguilar Ana Niembro-Zúñiga J. Amador Zarco Alfonso Marhx-Bracho Fernando Rueda-Franco Leticia Bornstein-Quevedo 《Child's nervous system》2007,23(5):543-547
Objective The purpose of this study is to analyze clinical aspects and disease-free survival (DFS) in children less than 3 years of
age diagnosed with low-grade astrocytoma.
Methods In a period of 24 years (1980–2004), a total of 43 (5.4%) children were registered with these characteristics. Twenty-three
patients had pilocytic astrocytoma, 18 diffused, and 2 mixed. Thirty-one (72.1%) children had incomplete surgical tumor resection
and 12 (27.9%) had a complete tumor resection. Twelve (27.9%) patients had cranial radiotherapy and 17 (39.5%) received chemotherapy.
Overall survival was recorded in 23 (53%). DFS was 50% at 250 months of follow-up for the whole group. DFS for the supratentorial
group was 60% at 250 months, whereas, for the infratentorial, it was 22% at 120 months (p = 0.008).
Conclusion The only favorable prognostic pattern was the supratentorial presentation. Radiotherapy and chemotherapy did not alter the
outcome. 相似文献
29.
Clemens Aigner Peter Jaksch Samy Mazhar Kriztina Czebe Gabriel Marta Sharokh Taghavi Georg Lang Walter Klepetko 《European journal of cardio-thoracic surgery》2004,25(2):184-187
OBJECTIVES: The use of OKT3 for treatment of advanced high-grade acute rejection episodes eventually can result in cytokine release and consecutive pulmonary edema. Temporary extracorporeal membrane oxygenation (ECMO) bridging can be used to overcome this crucial period before the beneficial effects of OKT3 can be observed. METHODS: We summarize our experience with three patients, who underwent lung transplantation and presented with severe acute rejection episodes. OKT3 had to be initiated due to insufficient response to standard rejection therapy with corticosteroids. Upon initiation of OKT3 treatment, a massive life-threatening deterioration of lung function in spite of heavily invasive respirator treatment was seen and temporary ECMO support was imperative to support graft function. Results of this treatment were retrospectively reviewed. RESULTS: In all cases femoro-femoral veno-arterial ECMO was used for support of the impaired graft and after a period of 4-5 days led to a massive improvement of graft function. In the further course two patients could be discharged from hospital and are still alive 30 and 36 months, respectively, after the described incident. One patient died 4 months later due to liver failure. CONCLUSIONS: We conclude that the use of ECMO support in patients experiencing significant side effects from OKT3 therapy is a useful and effective therapeutic tool to overcome the initial critical period until the lung has sufficiently recovered. 相似文献
30.