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1.
Int J Radiat Oncol Biol Phys ; 51(1): 23-30, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11516847

RESUMO

PURPOSE: Population-based cancer registries can permit the study of the survivorship of all patients with a particular diagnosis regardless of patterns of referral and practice within a specific geographic distribution. The purpose of this study is to describe the patterns of care, outcome, and prognostic factors for bladder cancer in the northern region of the province of Alberta, Canada, between 1984 and 1993. METHODS AND MATERIALS: Between 1984 and 1993, 184 patients from northern Alberta were identified from the Alberta Cancer Registry as having undergone curative treatment for biopsy-proven muscle-invasive transitional cell carcinoma of the bladder. Data were obtained, by retrospective chart review, regarding the staging, pathology, treatment, and outcome of patients treated in the northern Alberta cities of Edmonton, Grande Prairie, and Red Deer, regardless of the responsible treating institution. The prognostic significance of patient-, tumor-, and treatment-related variables were tested using univariate and multivariate analysis using the Cox proportional-hazard model. RESULTS: As the primary treatment modality, 74 patients (40%) received radical radiotherapy (RT) without surgery; surgery was used alone in 81 patients (44%), and was combined with preoperative or postoperative radiotherapy in 29 patients (16%). Seventy-three (40%) patients also received concurrent, neoadjuvant, or adjuvant chemotherapy. The Kaplan-Meier estimate of median survival was 2.2 years, and the 5-year overall survival was 30%. Univariate analysis demonstrated the prognostic significance of T classification (p < 0.001), lymph node involvement (p < 0.001), complete response to RT (p = 0.001), hydronephrosis (p = 0.017), and vascular/lymphatic involvement (p = 0.035). Multivariate analysis revealed the following to have a significant association with survival: T classification (p = 0.001), lymph node involvement (p = 0.004), complete response to RT (p = 0.054), hydronephrosis (p = 0.019), and use of chemotherapy in the treatment regimen (p = 0.025). CONCLUSION: The strongest prognostic factors in this study were tumor related, and no significant differences in survival were detected between patients treated with primary surgery vs. organ-preservation approaches. A survival advantage associated with the incorporation of chemotherapy into the management schema was detected on multivariate, but not univariate, analysis. Stratification of patients based on tumor characteristics is imperative in clinical trials for invasive bladder cancer. Novel treatment approaches are required to improve survival further in patients with apparently localized disease.


Assuntos
Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/terapia , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Carcinoma de Células de Transição/patologia , Quimioterapia Adjuvante , Terapia Combinada , Cistectomia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Radioterapia , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento , Neoplasias da Bexiga Urinária/patologia
2.
Fertil Steril ; 55(5): 1014-6, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-1708730

RESUMO

Anaphylactic reaction associated with hysteroscopy using 32% dextran-70 as a distending medium is a rare phenomenon. We report anaphylactic reaction associated with hysteroscopy using dextran that was delivered manually in three otherwise healthy women occurring within a 6-month period. The rapidity and pressure of dextran administered might facilitate intravascular absorption and predispose patients to this phenomenon.


Assuntos
Anafilaxia/induzido quimicamente , Dextranos/efeitos adversos , Histeroscopia , Adulto , Dextranos/administração & dosagem , Feminino , Humanos , Pessoa de Meia-Idade , Peso Molecular
3.
Am J Bot ; 88(1): 62-7, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11159127

RESUMO

Salinity reduces substrate water potential, thereby restricting water and nutrient uptake by plants; salinity may also cause ionic imbalance and toxicity. Because substrate salinity fluctuates through the growing season, a plant may be exposed to different salinity levels, at various stages of development, with potentially significant consequences on population dynamics. Here, we present the results of a study of the effect of substrate salinity on seed germination, seedling emergence, and growth of Aster laurentianus, an annual marsh plant, endemic to the Gulf of St. Lawrence and potentially threatened. Seed germination was reduced in low salt concentration (10 g sea salt/L) and completely inhibited by salinity levels >/=20 g sea salt/L. However, this inhibiting effect was reversible: seeds from the salt treatments germinated readily after being washed in distilled water. Though seedling emergence was diminished at low salinity levels, postemergence survival was little affected. Plant growth was reduced, but net carbon assimilation rate was not affected by high salinity levels. Increased root respiration and respiratory costs associated with salt tolerance might have contributed to lower C accumulation at higher salinity levels. All developmental processes considered are thus negatively affected by substrate salinity, with potentially significant consequences on population abundance and distribution in salt marshes. Yet, the tolerance of this species to high salinity levels after seedling emergence is remarkable. Seed germination represents a major bottleneck in the species life cycle, potentially controlling local distribution and abundance in the natural habitat.

4.
Dalton Trans ; 41(48): 14568-82, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23052471

RESUMO

Four new organotin(IV) complexes of bis-(2,6-di-tert-butylphenol)tin(IV) dichloride [(tert-Bu-)(2)(HO-Ph)](2)SnCl(2) (1) with the heterocyclic thioamides 2-mercapto-pyrimidine (PMTH), 2-mercapto-4-methyl-pyrimidine (MPMTH), 2-mercapto-pyridine (PYTH) and 2-mercapto-benzothiazole (MBZTH), of formulae {[(tert-Bu-)(2)(HO-Ph)](2)Sn(PMT)(2)} (2), {[(tert-Bu-)(2)(HO-Ph)](2)Sn(MPMT)(2)} (3), {[(tert-Bu-)(2)(HO-Ph)](2)SnCl(PYT)} (4) and {[(tert-Bu-)(2)(HO-Ph)](2)SnCl(MBZT)} (5), have been synthesized and characterized by elemental analysis, (1)H-, (13)C-, (119)Sn-NMR, EPR, FT-IR, Raman and Mössbauer spectroscopic techniques. The crystal and molecular structures of compounds 1­5 have been determined by X-ray diffraction. The geometries around the metal center adopted in complexes 1­5 varied between tetrahedral in 1, trigonal bipyramidal in 3, 4, 5 and distorted octahedral in 2. Two carbon atoms from aryl groups and two chlorine atoms form a distorted tetrahedron in the case of 1. Two carbon, two sulfur and two nitrogen atoms from thione ligands form a distorted octahedral geometry around tin(IV) with trans-C(2), cis-N(2), cis-S(2)-configurations in 2. However, in the case of 4 and 5 complexes two carbon, one sulfur, one nitrogen and one chloride atom form a distorted trigonal bipyramidal arrangement. Finally, in the case of 3 the trigonal bipyramidal geometry is achieved by two carbon, two sulfur and one nitrogen atom in a unique coordination mode of thioamides toward the tin(IV) cation. Compounds 1­5 were tested for their in vitro cytotoxicity against the human breast adenocarcinoma (MCF-7) cell line. Compound 3 exhibits strong cytotoxic activity against MCF-7 cells (IC(50) = 0.58 ± 0.1 µM).


Assuntos
Complexos de Coordenação/síntese química , Estanho/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Biologia Computacional , Complexos de Coordenação/toxicidade , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células HeLa , Humanos , Isomerismo , Células MCF-7 , Conformação Molecular , Análise de Componente Principal , Pirimidinas/química , Tioamidas/química
6.
Am J Bot ; 84(12): 1729, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21708578

RESUMO

Both abiotic conditions and resource levels affect the performance of plants on coastal dune systems. On the foredune, environmental factors are particularly limiting for plant growth and these vary along a short topographical gradient, from the foot to the ridge. On subarctic coastal dunes in northeastern Canada, this topographical gradient is paralleled by a plant sequence that typically involves Honckenya peploides, Elymus mollis, and Lathyrus japonicus. In this study, field nutrient additions were carried out to evaluate the importance of N and/or P limitation on foredune plant performance. Also, glasshouse experiments were done to determine the significance of interactions between substrate resources (i.e., nutrients and water), and between substrate resources (i.e., nutrients) and an abiotic condition (i.e., salt spray) on the growth of a dune species. Field nutrient additions did not result in any significant increase in plant biomass, although nutrients were accumulated in the rhizomes of all three species present on the foredune and in the aboveground tissues of Elymus. Glasshouse experiments on Elymus showed that nutrient addition could increase plant biomass. However, water availability and salt spray interfered with nutrient use by the plants. I suggest that such interactions between resources and abiotic conditions may significantly affect plant performance and plant sequence on the foredune of coastal dune systems.

7.
Am J Bot ; 84(7): 928, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21708647

RESUMO

The presence of conflicts in the allocation of resources among the different functions of an organism is a fundamental postulate of modern ecology. It is assumed that reproduction occurs at a cost because it monopolizes resources that could be used for other functions (e.g., growth). These conflicts may be particularly evident under stressful conditions, such as under low water or nutrient availability, or under severe climatic conditions. There we may expect to find strong negative relationships between an organism's growth and reproduction. We studied a population of Pinus banksiana (Pinaceae) at the northern limit of the species distribution, in subarctic Québec (Canada) where Pinus banksiana occupies nutrient-poor, sandy terraces along the Great Whale river. Serotinous cones of Pinus banksiana produced between 1969 and 1992 were sampled to estimate interannual variations in several variables representing reproduction, and to relate these to climate and tree growth. Climate appears to influence each developmental stage involved in the production of viable seeds, from the time of cone initiation to that of seed maturation. In general, reproductive variables are positively related to high temperatures during the three growing seasons required for seed production; growth is also positively correlated to summer temperatures. Consequently, investment in maturing seeds is positively associated with growth. Thus, both reproduction and growth covary with climate: during relatively warm and long growing seasons, resource allocation to both functions increases. Under these conditions, no trade-off is apparent.

8.
Am J Bot ; 88(4): 659-66, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11302852

RESUMO

Males and females of dioecious plant species often differ in their reproductive investment. Such differences frequently result in differential demographic costs represented by lower growth, survival, and/or frequency of reproduction, and/or by more variable reproductive effort through time for females. We present the results of a study on Corema conradii, a rare dioecious shrub of the coastal dune heathlands of northeastern North America. We estimated the reproductive investment of both males and females, determined their age structure, and compared their spatial patterns in a population at Îles-de-la-Madeleine, Quebec. We also determined the sex ratio of the four populations known to occur on the islands. Males invested more in reproduction at flowering, but when fruit production was considered, female reproductive investment was higher in terms of biomass, Mg, and Ca, but not in terms of N, P, and K. The age frequency distribution of males and females did not differ significantly from one another. The population dispersion pattern was contagious, with patches of similar-age individuals. There was no spatial segregation between males and females, although the sex ratio varied somewhat spatially. Females did not start reproducing at a later age than males and did not appear to have a shorter longevity. However, the crown and radial growth rates of females were lower than those of males. When estimated by the crown intercept method, the sex ratio of all four populations was male biased. However, because males had a higher crown growth rate, genet sex ratio was in fact balanced. Higher investment in reproduction was associated with a lower growth rate, which represents a differential cost of reproduction according to sex in this species.

9.
Am J Obstet Gynecol ; 121(8): 1080-3, 1975 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-1119501

RESUMO

Oxygen consumption, tidal volume, and minute volume decreased in 20 patients during the first stage of labor after either epidural or paracervical block. The elimination of pain with optimum regional analgesia is associated with a decrease in tidal and minute volumes, apprehension, and consequently a decreased oxygen consumption. These factors may contribute to a decrease in maternal lactic acidosis during labor.


Assuntos
Anestesia Epidural/efeitos adversos , Anestesia Obstétrica/efeitos adversos , Cesárea/métodos , Bloqueio Nervoso/efeitos adversos , Consumo de Oxigênio , Adulto , Feminino , Humanos , Dor , Gravidez , Testes de Função Respiratória
10.
Can Anaesth Soc J ; 22(1): 79-83, 1975 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-234025

RESUMO

Lidocaine concentrations were measured after vaginal delivery or Caesarean section with epidural anaesthesia in samples of maternal and umbilical blood and in newborn gastric contents. The pH of the gastric aspirate was also determined in a number of neonates. Gastric lidocaine concentrations were higher and the pH was lower after vaginal delivery in comparison to Caesarean section. A significant inverse correlation exists between gastric pH and gastric lidocaine concentration, Neonate gastric lidocaine concentration was significantly higher than in maternal or umbilical venous plasma after vaginal delivery, but not after Caesarean section. Due to these differences, gastric lavage for the treatment of neonatal lidocaine intoxication may be more beneficial in reducing foetal systemic local anaesthetic concentration after vaginal than after elective abdominal delivery.


Assuntos
Anestesia Epidural , Anestesia Obstétrica , Suco Gástrico/análise , Recém-Nascido , Lidocaína/análise , Cesárea , Parto Obstétrico , Feminino , Determinação da Acidez Gástrica , Lavagem Gástrica , Humanos , Concentração de Íons de Hidrogênio , Lidocaína/sangue , Troca Materno-Fetal , Gravidez , Artérias Umbilicais , Veias Umbilicais , Vagina
11.
Am J Bot ; 88(4): 594-607, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11302844

RESUMO

Because environmental filters are temporally and spatially heterogeneous, there often is a lack of significant relationship between the spatial patterns of successive life stages in plant populations. In this study, we determined the spatiotemporal relationships between different life stages in two populations of an annual plant of the deciduous forests of eastern North America, Floerkea proserpinacoides. Demographic surveys were done over a 4-yr period, and experiments were performed in the field and under controlled conditions to test for the effects of various environmental factors on population dynamics. There was a general lack of relationship between the spatial patterns of seed bank and seedling density, and a lack of similarity between their spatial correlograms. This was related mostly to the effects of spatially variable environmental filters operating on germination and emergence. However, environmental filters acting on plant survival were stable through time and contributed to stabilize the density and spatial patterns of the populations. Despite density-dependent presenescence mortality, spatial patterns of seedlings and mature individuals were similar and their correlograms were alike, suggesting that mortality did not fully compensate for density. Estimated fecundity was negatively correlated with population density over the study period. Although flower production started only 2-3 wk after emergence, seed maturation mostly occurred at the end of the life cycle, just before the onset of plant senescence. Yet, individual fecundity was low for an annual plant, i.e., 3.0 ± 0.5 mature seeds/plant (mean ± 1 SE). Seed predation by vertebrates was not significant. Low soil moisture had little effect on the total number of seeds germinating, although it slowed down the germination process. In quadrats where leaf litter was experimentally doubled, seedling emergence was lower than in control quadrats; in quadrats where leaf litter was completely removed, emergence did not differ from that in control quadrats. Susceptibility to drought stress was higher for seedlings than for mature plants. Although the species does not maintain a long-term persistent soil seed bank, other factors, such as density-dependent fecundity and autogamy, may temper population fluctuations through time and reduce the probability of local extinction.

12.
Can Anaesth Soc J ; 32(3 Pt 2): S47-51, 1985 May.
Artigo em Inglês | MEDLINE | ID: mdl-4005695
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