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排序方式: 共有1485条查询结果,搜索用时 15 毫秒
1.
Infection of rat liver by Taenia taeniformis metacestodes produced an increase in total CYP450 content and induced activity of the CYP1A1, CYP2B1 and COH isoforms. Variations in activity and p450 total content were found with increasing time of infection. During increased activity of p450 isoforms, rats were challenged with carcinogens metabolized by the mentioned isozymes and an increased amount of genotoxic damage was found when benzo[a] pyrene, cyclophosphamide and aflatoxin B(1) were used. No change was seen in CYP2E1 activity. These results support previous findings regarding an increased susceptibility to genotoxic damage of infected organisms. 相似文献
2.
Salamanca J Rodríguez-Peralto JL Azorín D Ballestín C De Agustín P 《Diagnostic cytopathology》2004,30(1):46-50
We report the FNA features of a congenital malignant extrarenal rhabdoid tumor (MERT) located in the right paratesticular area of a newborn full-term boy (39 wk gestation), with disseminated metastases in the liver and right parietal region. The diagnosis was suggested two days after birth by fine-needle aspiration biopsy (FNAB) of the parietal mass, which demonstrated an atypical large cell proliferation with vesicular nuclei, prominent nucleoli, and abundant cytoplasm exhibiting paranuclear dense inclusions. The diagnosis was confirmed by histopathologic and immunohistochemical examination of the primary paratesticular tumor. To the best of our knowledge, this is the third MERT reported in the paratesticular region, one of the few congenital extrarenal non-central nervous system cases, and the third congenital case (renal or extrarenal) primarily diagnosed by FNAB. We emphasize the characteristic cytologic features of a congenital rhabdoid tumor, which must be known by pathologists because of the clinical and prognostic implications. Diagn. Cytopathol. 2004;30:46-50. 相似文献
3.
BACKGROUND: Because little is known about micronutrient/antioxidant intake and asthma severity, we investigated dietary intake and plasma/serum levels of micronutrients/antioxidants in a group of asthma patients with various degrees of severity, and compared the results with healthy subjects. METHODS: A case control study was carried out on 118 asthma patients and 121 healthy subjects. The severity of the disease was classified by division of patients into four groups. Normal dietary micronutrient/antioxidant intake was estimated from a food frequency questionnaire. Plasma/serum levels of vitamins C, E, and A, selenium, magnesium, zinc, and platelet glutathione peroxidase (GSH-Px) activity were also determined. RESULTS: No differences in daily micronutrient/antioxidant intake were seen between patients and healthy subjects. The severity of the disease showed no significant relationship with micronutrient/antioxidant intake. There were no differences in plasma/serum levels in any of the micronutrients/antioxidants between healthy subjects and asthmatics. Nor were any differences found between asthma groups in severity in the biochemical measures, except in platelet GSH-Px activity, which was significantly lower in the most severe groups. CONCLUSIONS: In this study, we found no evidence of any association between micronutrient/antioxidant intake or plasma/serum levels of micronutrients/antioxidants and asthma. Reduction of platelet GSH-Px activity in the most severe patients suggests that these patients have a diminished capacity to restore part of the antioxidant defences. 相似文献
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de Agustín JC Zabala JI Zunzunegui JL Medrano C Maroto E Maroto C Blanco T Luque-Mialdea R Cerdá J Aguilar F Vázquez J 《Cirugía pediátrica : organo oficial de la Sociedad Espa?ola de Cirugía Pediátrica》1999,12(1):30-32
The haemodynamic changes produced by laparoscopic surgery in children have been evaluated. A transesophageal echocardiographic study on 13 patients (7 males and 6 females, 10.8 +/- 2.7 years old) has been performed before, during and after peritoneal CO2 gas insufflation. A change on the Doppler waves pattern of the infradiaphragmatic veins along with an increase in blood flow velocity were observed. Pulmonary veins suffered minimal changes showing an increase on either the systolic pressure and on atrial contraction. Diastolic retrograde flow in aorta reflected an increase in peripheral vascular resistance. Cardiac output increased minimally. All haemodynamic changes returned to basal after gas peritoneal desufflation. These data show that laparoscopic surgery could produce important cardiac derangements in children with ventricular dysfunction or in patients presenting left ventricular outlet obstruction. In these patients laparoscopic surgery might be precluded. 相似文献
6.
Tania Crombet Marta Osorio Teresa Cruz Carlos Roca Ramón del Castillo Rosa Mon Normando Iznaga-Escobar René Figueredo James Koropatnick Enrique Renginfo Eduardo Fernández Daniel Alvárez Olga Torres Mayra Ramos Idrissa Leonard Rolando Pérez Agustín Lage 《Journal of clinical oncology》2004,22(9):1646-1654
PURPOSE: To evaluate safety and preliminary efficacy of the humanized anti-epidermal growth factor receptor monoclonal antibody h-R3 in combination with radiotherapy (RT) in unresectable head and neck cancer patients. Secondary end points were the measurement of h-R3 serum levels and the assessment of the potential mechanisms of antitumor effect on patient biopsies. Anti-idiotypic response to h-R3 was assessed. To predict pharmacologic effect, a mathematical model for antibodies recognizing antigens expressed in tumors and normal tissues was built. PATIENTS AND METHODS: Twenty-four patients with advanced carcinomas of the head and neck received six once-weekly infusions of h-R3 at four dose levels in combination with RT. Pretreatment tumor biopsies were obtained to evaluate epidermal growth factor receptor expression as an enrollment criterion. Second biopsies were taken to evaluate the proliferative activity and angiogenesis in comparison with the pretreatment samples. Patient serum samples were collected to measure h-R3 levels and anti-idiotypic response. RESULTS: The combination of h-R3 and RT was well tolerated. Antibody-related adverse events consisted in infusion reactions. No skin or allergic toxicity appeared. Overall survival significantly increased after the use of the higher antibody doses. Immunohistochemistry studies of tumor specimens before and after treatment revealed that antitumor response correlated with antiproliferative and antiangiogenic effect. One patient developed antibodies to h-R3. The mathematical model predicted that the maximum difference between the area under the curve in tumors and normal tissues is reached when the antibody has intermediate affinity. CONCLUSION: h-R3 is a well-tolerated drug that may enhance radiocurability of unresectable head and neck neoplasms. 相似文献
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LA Henriquez-Hernandez M Moreno A Rey M Lloret PC Lara 《Radiation oncology (London, England)》2012,7(1):147
ABSTRACT: OBJECTIVE: Explore the role of Major Vault Protein (MVP) in oral cavity squamous cell carcinoma patients.Subjects and Methods131 consecutive patients suffering from oral cavity squamous cell carcinoma were included in the study. In the whole series, the mean follow-up for survivors was 123.11 [PLUS-MINUS SIGN] 40.36 months. Patients in tumour stages I and II were referred to surgery; patients in stage III-IV to postoperative radiotherapy (mean dose = 62.13 [PLUS-MINUS SIGN] 7.74 Gy in 1.8--2 Gy/fraction). MVP expression was studied by immunohistochemistry in paraffin-embedded tumour tissue. RESULTS: MVP expression was positive in 112 patients (85.5 %) and no relation was found with clinic pathological variables. MVP overexpression (those tumours with moderate or strong expression of the protein) was related to insulin-like growth factor receptor-1 (IGF-1R) expression (P = 0.014). Tumour stage of the disease was the most important prognostic factor related to survival. Tumours overexpressing MVP and IGF-1R were strongly related to poor disease-free survival (P = 0.008, Exp(B) = 2.730, CI95% (1.302-5.724)) and cause-specific survival (P = 0.014, Exp(B) = 2.570, CI95% (1.215-5.437)) in patients achieving tumour stages III-IV, in multivariate analysis. CONCLUSIONS: MVP and IGF-1R expression were related in oral squamous cell carcinoma and conferred reduced long-term survival in patients suffering from advanced stages of the disease. 相似文献
10.
Agustín Conde‐Agudelo Anyeli Rosas‐Bermudez Fabio Castaño Maureen H. Norton 《Studies in family planning》2012,43(2):93-114
This systematic review of 58 observational studies identified hypothetical causal mechanisms explaining the effects of short and long intervals between pregnancies on maternal, perinatal, infant, and child health, and critically examined the scientific evidence for each causal mechanism hypothesized. The following hypothetical causal mechanisms for explaining the association between short intervals and adverse outcomes were identified: maternal nutritional depletion, folate depletion, cervical insufficiency, vertical transmission of infections, suboptimal lactation related to breastfeeding–pregnancy overlap, sibling competition, transmission of infectious diseases among siblings, incomplete healing of uterine scar from previous cesarean delivery, and abnormal remodeling of endometrial blood vessels. Women's physiological regression is the only hypothetical causal mechanism that has been proposed to explain the association between long intervals and adverse outcomes. We found growing evidence supporting most of these hypotheses. 相似文献